* [PATCH v21 01/24] net: introduce OpenVPN Data Channel Offload (ovpn)
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 02/24] ovpn: add basic netlink support Antonio Quartulli
` (22 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang,
steffen.klassert, antony.antony
OpenVPN is a userspace software existing since around 2005 that allows
users to create secure tunnels.
So far OpenVPN has implemented all operations in userspace, which
implies several back and forth between kernel and user land in order to
process packets (encapsulate/decapsulate, encrypt/decrypt, rerouting..).
With `ovpn` we intend to move the fast path (data channel) entirely
in kernel space and thus improve user measured throughput over the
tunnel.
`ovpn` is implemented as a simple virtual network device driver, that
can be manipulated by means of the standard RTNL APIs. A device of kind
`ovpn` allows only IPv4/6 traffic and can be of type:
* P2P (peer-to-peer): any packet sent over the interface will be
encapsulated and transmitted to the other side (typical OpenVPN
client or peer-to-peer behaviour);
* P2MP (point-to-multipoint): packets sent over the interface are
transmitted to peers based on existing routes (typical OpenVPN
server behaviour).
After the interface has been created, OpenVPN in userspace can
configure it using a new Netlink API. Specifically it is possible
to manage peers and their keys.
The OpenVPN control channel is multiplexed over the same transport
socket by means of OP codes. Anything that is not DATA_V2 (OpenVPN
OP code for data traffic) is sent to userspace and handled there.
This way the `ovpn` codebase is kept as compact as possible while
focusing on handling data traffic only (fast path).
Any OpenVPN control feature (like cipher negotiation, TLS handshake,
rekeying, etc.) is still fully handled by the userspace process.
When userspace establishes a new connection with a peer, it first
performs the handshake and then passes the socket to the `ovpn` kernel
module, which takes ownership. From this moment on `ovpn` will handle
data traffic for the new peer.
When control packets are received on the link, they are forwarded to
userspace through the same transport socket they were received on, as
userspace is still listening to them.
Some events (like peer deletion) are sent to a Netlink multicast group.
Although it wasn't easy to convince the community, `ovpn` implements
only a limited number of the data-channel features supported by the
userspace program.
Each feature that made it to `ovpn` was attentively vetted to
avoid carrying too much legacy along with us (and to give a clear cut to
old and probalby-not-so-useful features).
Notably, only encryption using AEAD ciphers (specifically
ChaCha20Poly1305 and AES-GCM) was implemented. Supporting any other
cipher out there was not deemed useful.
Both UDP and TCP sockets are supported.
As explained above, in case of P2MP mode, OpenVPN will use the main system
routing table to decide which packet goes to which peer. This implies
that no routing table was re-implemented in the `ovpn` kernel module.
This kernel module can be enabled by selecting the CONFIG_OVPN entry
in the networking drivers section.
NOTE: this first patch introduces the very basic framework only.
Features are then added patch by patch, however, although each patch
will compile and possibly not break at runtime, only after having
applied the full set it is expected to see the ovpn module fully working.
Cc: steffen.klassert@secunet.com
Cc: antony.antony@secunet.com
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
MAINTAINERS | 8 ++++
drivers/net/Kconfig | 8 ++++
drivers/net/Makefile | 1 +
drivers/net/ovpn/Makefile | 10 +++++
drivers/net/ovpn/main.c | 112 ++++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 139 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 7078199fcebf2d22bc722f0f7654e98f7b94fa6c..7a96fd7ac9bcf09a81542a69e7d8b9102a31c4e9 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17749,6 +17749,14 @@ F: arch/openrisc/
F: drivers/irqchip/irq-ompic.c
F: drivers/irqchip/irq-or1k-*
+OPENVPN DATA CHANNEL OFFLOAD
+M: Antonio Quartulli <antonio@openvpn.net>
+L: openvpn-devel@lists.sourceforge.net (subscribers-only)
+L: netdev@vger.kernel.org
+S: Supported
+T: git https://github.com/OpenVPN/linux-kernel-ovpn.git
+F: drivers/net/ovpn/
+
OPENVSWITCH
M: Pravin B Shelar <pshelar@ovn.org>
L: netdev@vger.kernel.org
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 1fd5acdc73c6af0e1a861867039c3624fc618e25..2ace5e27c37ed3bad2e0000775cd172cb6de3225 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -115,6 +115,14 @@ config WIREGUARD_DEBUG
Say N here unless you know what you're doing.
+config OVPN
+ tristate "OpenVPN data channel offload"
+ depends on NET && INET
+ depends on IPV6 || !IPV6
+ help
+ This module enhances the performance of the OpenVPN userspace software
+ by offloading the data channel processing to kernelspace.
+
config EQUALIZER
tristate "EQL (serial line load balancing) support"
help
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 13743d0e83b5fde479e9b30ad736be402d880dee..5152b3330e28da7eaec821018a26c973bb33ce0c 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_IPVLAN) += ipvlan/
obj-$(CONFIG_IPVTAP) += ipvlan/
obj-$(CONFIG_DUMMY) += dummy.o
obj-$(CONFIG_WIREGUARD) += wireguard/
+obj-$(CONFIG_OVPN) += ovpn/
obj-$(CONFIG_EQUALIZER) += eql.o
obj-$(CONFIG_IFB) += ifb.o
obj-$(CONFIG_MACSEC) += macsec.o
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
new file mode 100644
index 0000000000000000000000000000000000000000..876800ebaa21a5f758ddf60f637801710437f70e
--- /dev/null
+++ b/drivers/net/ovpn/Makefile
@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# ovpn -- OpenVPN data channel offload in kernel space
+#
+# Copyright (C) 2020-2025 OpenVPN, Inc.
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+
+obj-$(CONFIG_OVPN) := ovpn.o
+ovpn-y += main.o
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
new file mode 100644
index 0000000000000000000000000000000000000000..e816e8fbbfeff1086a55c858b1941b7d82d7aba6
--- /dev/null
+++ b/drivers/net/ovpn/main.c
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ * James Yonan <james@openvpn.net>
+ */
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <net/rtnetlink.h>
+
+static const struct net_device_ops ovpn_netdev_ops = {
+};
+
+/**
+ * ovpn_dev_is_valid - check if the netdevice is of type 'ovpn'
+ * @dev: the interface to check
+ *
+ * Return: whether the netdevice is of type 'ovpn'
+ */
+static bool ovpn_dev_is_valid(const struct net_device *dev)
+{
+ return dev->netdev_ops == &ovpn_netdev_ops;
+}
+
+static int ovpn_newlink(struct net_device *dev,
+ struct rtnl_newlink_params *params,
+ struct netlink_ext_ack *extack)
+{
+ return -EOPNOTSUPP;
+}
+
+static struct rtnl_link_ops ovpn_link_ops = {
+ .kind = "ovpn",
+ .netns_refund = false,
+ .newlink = ovpn_newlink,
+ .dellink = unregister_netdevice_queue,
+};
+
+static int ovpn_netdev_notifier_call(struct notifier_block *nb,
+ unsigned long state, void *ptr)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+ if (!ovpn_dev_is_valid(dev))
+ return NOTIFY_DONE;
+
+ switch (state) {
+ case NETDEV_REGISTER:
+ /* add device to internal list for later destruction upon
+ * unregistration
+ */
+ break;
+ case NETDEV_UNREGISTER:
+ /* can be delivered multiple times, so check registered flag,
+ * then destroy the interface
+ */
+ break;
+ case NETDEV_POST_INIT:
+ case NETDEV_GOING_DOWN:
+ case NETDEV_DOWN:
+ case NETDEV_UP:
+ case NETDEV_PRE_UP:
+ default:
+ return NOTIFY_DONE;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block ovpn_netdev_notifier = {
+ .notifier_call = ovpn_netdev_notifier_call,
+};
+
+static int __init ovpn_init(void)
+{
+ int err = register_netdevice_notifier(&ovpn_netdev_notifier);
+
+ if (err) {
+ pr_err("ovpn: can't register netdevice notifier: %d\n", err);
+ return err;
+ }
+
+ err = rtnl_link_register(&ovpn_link_ops);
+ if (err) {
+ pr_err("ovpn: can't register rtnl link ops: %d\n", err);
+ goto unreg_netdev;
+ }
+
+ return 0;
+
+unreg_netdev:
+ unregister_netdevice_notifier(&ovpn_netdev_notifier);
+ return err;
+}
+
+static __exit void ovpn_cleanup(void)
+{
+ rtnl_link_unregister(&ovpn_link_ops);
+ unregister_netdevice_notifier(&ovpn_netdev_notifier);
+
+ rcu_barrier();
+}
+
+module_init(ovpn_init);
+module_exit(ovpn_cleanup);
+
+MODULE_DESCRIPTION("OpenVPN data channel offload (ovpn)");
+MODULE_AUTHOR("(C) 2020-2025 OpenVPN, Inc.");
+MODULE_LICENSE("GPL");
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 02/24] ovpn: add basic netlink support
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 01/24] net: introduce OpenVPN Data Channel Offload (ovpn) Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 03/24] ovpn: add basic interface creation/destruction/management routines Antonio Quartulli
` (21 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
This commit introduces basic netlink support with family
registration/unregistration functionalities and stub pre/post-doit.
More importantly it introduces the YAML uAPI description along
with its auto-generated files:
- include/uapi/linux/ovpn.h
- drivers/net/ovpn/netlink-gen.c
- drivers/net/ovpn/netlink-gen.h
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
Documentation/netlink/specs/ovpn.yaml | 371 ++++++++++++++++++++++++++++++++++
MAINTAINERS | 2 +
drivers/net/ovpn/Makefile | 2 +
drivers/net/ovpn/main.c | 17 +-
drivers/net/ovpn/main.h | 14 ++
drivers/net/ovpn/netlink-gen.c | 213 +++++++++++++++++++
drivers/net/ovpn/netlink-gen.h | 41 ++++
drivers/net/ovpn/netlink.c | 160 +++++++++++++++
drivers/net/ovpn/netlink.h | 15 ++
drivers/net/ovpn/ovpnpriv.h | 21 ++
include/uapi/linux/ovpn.h | 110 ++++++++++
11 files changed, 965 insertions(+), 1 deletion(-)
diff --git a/Documentation/netlink/specs/ovpn.yaml b/Documentation/netlink/specs/ovpn.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..4d4e2a3662f051b0b05ef785c0c9b0804ebb677d
--- /dev/null
+++ b/Documentation/netlink/specs/ovpn.yaml
@@ -0,0 +1,371 @@
+# SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+#
+# Copyright (c) 2024-2025, OpenVPN Inc.
+#
+
+name: ovpn
+
+protocol: genetlink
+
+doc: Netlink protocol to control OpenVPN network devices
+
+definitions:
+ -
+ type: const
+ name: nonce-tail-size
+ value: 8
+ -
+ type: enum
+ name: cipher-alg
+ entries: [ none, aes-gcm, chacha20-poly1305 ]
+ -
+ type: enum
+ name: del-peer-reason
+ entries:
+ - teardown
+ - userspace
+ - expired
+ - transport-error
+ - transport-disconnect
+ -
+ type: enum
+ name: key-slot
+ entries: [ primary, secondary ]
+
+attribute-sets:
+ -
+ name: peer
+ attributes:
+ -
+ name: id
+ type: u32
+ doc: >-
+ The unique ID of the peer in the device context. To be used to identify
+ peers during operations for a specific device
+ checks:
+ max: 0xFFFFFF
+ -
+ name: remote-ipv4
+ type: u32
+ doc: The remote IPv4 address of the peer
+ byte-order: big-endian
+ display-hint: ipv4
+ -
+ name: remote-ipv6
+ type: binary
+ doc: The remote IPv6 address of the peer
+ display-hint: ipv6
+ checks:
+ exact-len: 16
+ -
+ name: remote-ipv6-scope-id
+ type: u32
+ doc: The scope id of the remote IPv6 address of the peer (RFC2553)
+ -
+ name: remote-port
+ type: u16
+ doc: The remote port of the peer
+ byte-order: big-endian
+ checks:
+ min: 1
+ -
+ name: socket
+ type: u32
+ doc: The socket to be used to communicate with the peer
+ -
+ name: socket-netnsid
+ type: s32
+ doc: The ID of the netns the socket assigned to this peer lives in
+ -
+ name: vpn-ipv4
+ type: u32
+ doc: The IPv4 address assigned to the peer by the server
+ byte-order: big-endian
+ display-hint: ipv4
+ -
+ name: vpn-ipv6
+ type: binary
+ doc: The IPv6 address assigned to the peer by the server
+ display-hint: ipv6
+ checks:
+ exact-len: 16
+ -
+ name: local-ipv4
+ type: u32
+ doc: The local IPv4 to be used to send packets to the peer (UDP only)
+ byte-order: big-endian
+ display-hint: ipv4
+ -
+ name: local-ipv6
+ type: binary
+ doc: The local IPv6 to be used to send packets to the peer (UDP only)
+ display-hint: ipv6
+ checks:
+ exact-len: 16
+ -
+ name: local-port
+ type: u16
+ doc: The local port to be used to send packets to the peer (UDP only)
+ byte-order: big-endian
+ checks:
+ min: 1
+ -
+ name: keepalive-interval
+ type: u32
+ doc: >-
+ The number of seconds after which a keep alive message is sent to the
+ peer
+ -
+ name: keepalive-timeout
+ type: u32
+ doc: >-
+ The number of seconds from the last activity after which the peer is
+ assumed dead
+ -
+ name: del-reason
+ type: u32
+ doc: The reason why a peer was deleted
+ enum: del-peer-reason
+ -
+ name: vpn-rx-bytes
+ type: uint
+ doc: Number of bytes received over the tunnel
+ -
+ name: vpn-tx-bytes
+ type: uint
+ doc: Number of bytes transmitted over the tunnel
+ -
+ name: vpn-rx-packets
+ type: uint
+ doc: Number of packets received over the tunnel
+ -
+ name: vpn-tx-packets
+ type: uint
+ doc: Number of packets transmitted over the tunnel
+ -
+ name: link-rx-bytes
+ type: uint
+ doc: Number of bytes received at the transport level
+ -
+ name: link-tx-bytes
+ type: uint
+ doc: Number of bytes transmitted at the transport level
+ -
+ name: link-rx-packets
+ type: u32
+ doc: Number of packets received at the transport level
+ -
+ name: link-tx-packets
+ type: u32
+ doc: Number of packets transmitted at the transport level
+ -
+ name: keyconf
+ attributes:
+ -
+ name: peer-id
+ type: u32
+ doc: >-
+ The unique ID of the peer in the device context. To be used to
+ identify peers during key operations
+ checks:
+ max: 0xFFFFFF
+ -
+ name: slot
+ type: u32
+ doc: The slot where the key should be stored
+ enum: key-slot
+ -
+ name: key-id
+ doc: >-
+ The unique ID of the key in the peer context. Used to fetch the
+ correct key upon decryption
+ type: u32
+ checks:
+ max: 7
+ -
+ name: cipher-alg
+ type: u32
+ doc: The cipher to be used when communicating with the peer
+ enum: cipher-alg
+ -
+ name: encrypt-dir
+ type: nest
+ doc: Key material for encrypt direction
+ nested-attributes: keydir
+ -
+ name: decrypt-dir
+ type: nest
+ doc: Key material for decrypt direction
+ nested-attributes: keydir
+ -
+ name: keydir
+ attributes:
+ -
+ name: cipher-key
+ type: binary
+ doc: The actual key to be used by the cipher
+ checks:
+ max-len: 256
+ -
+ name: nonce-tail
+ type: binary
+ doc: >-
+ Random nonce to be concatenated to the packet ID, in order to
+ obtain the actual cipher IV
+ checks:
+ exact-len: nonce-tail-size
+ -
+ name: ovpn
+ attributes:
+ -
+ name: ifindex
+ type: u32
+ doc: Index of the ovpn interface to operate on
+ -
+ name: ifname
+ type: string
+ doc: Name of the ovpn interface
+ -
+ name: peer
+ type: nest
+ doc: >-
+ The peer object containing the attributed of interest for the specific
+ operation
+ nested-attributes: peer
+ -
+ name: keyconf
+ type: nest
+ doc: Peer specific cipher configuration
+ nested-attributes: keyconf
+
+operations:
+ list:
+ -
+ name: peer-new
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: Add a remote peer
+ do:
+ pre: ovpn-nl-pre-doit
+ post: ovpn-nl-post-doit
+ request:
+ attributes:
+ - ifindex
+ - peer
+ -
+ name: peer-set
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: modify a remote peer
+ do:
+ pre: ovpn-nl-pre-doit
+ post: ovpn-nl-post-doit
+ request:
+ attributes:
+ - ifindex
+ - peer
+ -
+ name: peer-get
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: Retrieve data about existing remote peers (or a specific one)
+ do:
+ pre: ovpn-nl-pre-doit
+ post: ovpn-nl-post-doit
+ request:
+ attributes:
+ - ifindex
+ - peer
+ reply:
+ attributes:
+ - peer
+ dump:
+ request:
+ attributes:
+ - ifindex
+ reply:
+ attributes:
+ - peer
+ -
+ name: peer-del
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: Delete existing remote peer
+ do:
+ pre: ovpn-nl-pre-doit
+ post: ovpn-nl-post-doit
+ request:
+ attributes:
+ - ifindex
+ - peer
+ -
+ name: peer-del-ntf
+ doc: Notification about a peer being deleted
+ notify: peer-get
+ mcgrp: peers
+
+ -
+ name: key-new
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: Add a cipher key for a specific peer
+ do:
+ pre: ovpn-nl-pre-doit
+ post: ovpn-nl-post-doit
+ request:
+ attributes:
+ - ifindex
+ - keyconf
+ -
+ name: key-get
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: Retrieve non-sensitive data about peer key and cipher
+ do:
+ pre: ovpn-nl-pre-doit
+ post: ovpn-nl-post-doit
+ request:
+ attributes:
+ - ifindex
+ - keyconf
+ reply:
+ attributes:
+ - keyconf
+ -
+ name: key-swap
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: Swap primary and secondary session keys for a specific peer
+ do:
+ pre: ovpn-nl-pre-doit
+ post: ovpn-nl-post-doit
+ request:
+ attributes:
+ - ifindex
+ - keyconf
+ -
+ name: key-swap-ntf
+ notify: key-get
+ doc: >-
+ Notification about key having exhausted its IV space and requiring
+ renegotiation
+ mcgrp: peers
+ -
+ name: key-del
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: Delete cipher key for a specific peer
+ do:
+ pre: ovpn-nl-pre-doit
+ post: ovpn-nl-post-doit
+ request:
+ attributes:
+ - ifindex
+ - keyconf
+
+mcast-groups:
+ list:
+ -
+ name: peers
diff --git a/MAINTAINERS b/MAINTAINERS
index 7a96fd7ac9bcf09a81542a69e7d8b9102a31c4e9..1dd979149a1ae5de7af996252ad3385643368667 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17755,7 +17755,9 @@ L: openvpn-devel@lists.sourceforge.net (subscribers-only)
L: netdev@vger.kernel.org
S: Supported
T: git https://github.com/OpenVPN/linux-kernel-ovpn.git
+F: Documentation/netlink/specs/ovpn.yaml
F: drivers/net/ovpn/
+F: include/uapi/linux/ovpn.h
OPENVSWITCH
M: Pravin B Shelar <pshelar@ovn.org>
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
index 876800ebaa21a5f758ddf60f637801710437f70e..75ac62bba02937bc49cb2a0dec5ca3cc31a8ee00 100644
--- a/drivers/net/ovpn/Makefile
+++ b/drivers/net/ovpn/Makefile
@@ -8,3 +8,5 @@
obj-$(CONFIG_OVPN) := ovpn.o
ovpn-y += main.o
+ovpn-y += netlink.o
+ovpn-y += netlink-gen.o
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index e816e8fbbfeff1086a55c858b1941b7d82d7aba6..28133e7e15e74b8a4a937ed03f70d9f83d7a14c8 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -7,9 +7,15 @@
* James Yonan <james@openvpn.net>
*/
+#include <linux/genetlink.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <net/rtnetlink.h>
+#include <uapi/linux/ovpn.h>
+
+#include "ovpnpriv.h"
+#include "main.h"
+#include "netlink.h"
static const struct net_device_ops ovpn_netdev_ops = {
};
@@ -20,7 +26,7 @@ static const struct net_device_ops ovpn_netdev_ops = {
*
* Return: whether the netdevice is of type 'ovpn'
*/
-static bool ovpn_dev_is_valid(const struct net_device *dev)
+bool ovpn_dev_is_valid(const struct net_device *dev)
{
return dev->netdev_ops == &ovpn_netdev_ops;
}
@@ -89,8 +95,16 @@ static int __init ovpn_init(void)
goto unreg_netdev;
}
+ err = ovpn_nl_register();
+ if (err) {
+ pr_err("ovpn: can't register netlink family: %d\n", err);
+ goto unreg_rtnl;
+ }
+
return 0;
+unreg_rtnl:
+ rtnl_link_unregister(&ovpn_link_ops);
unreg_netdev:
unregister_netdevice_notifier(&ovpn_netdev_notifier);
return err;
@@ -98,6 +112,7 @@ static int __init ovpn_init(void)
static __exit void ovpn_cleanup(void)
{
+ ovpn_nl_unregister();
rtnl_link_unregister(&ovpn_link_ops);
unregister_netdevice_notifier(&ovpn_netdev_notifier);
diff --git a/drivers/net/ovpn/main.h b/drivers/net/ovpn/main.h
new file mode 100644
index 0000000000000000000000000000000000000000..017cd0100765900181cb662319cf38c2d0b7dd2d
--- /dev/null
+++ b/drivers/net/ovpn/main.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_MAIN_H_
+#define _NET_OVPN_MAIN_H_
+
+bool ovpn_dev_is_valid(const struct net_device *dev);
+
+#endif /* _NET_OVPN_MAIN_H_ */
diff --git a/drivers/net/ovpn/netlink-gen.c b/drivers/net/ovpn/netlink-gen.c
new file mode 100644
index 0000000000000000000000000000000000000000..9ba4e7eea1f29e657323d3200f5dd7df0357bfd2
--- /dev/null
+++ b/drivers/net/ovpn/netlink-gen.c
@@ -0,0 +1,213 @@
+// SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)
+/* Do not edit directly, auto-generated from: */
+/* Documentation/netlink/specs/ovpn.yaml */
+/* YNL-GEN kernel source */
+
+#include <net/netlink.h>
+#include <net/genetlink.h>
+
+#include "netlink-gen.h"
+
+#include <uapi/linux/ovpn.h>
+
+/* Integer value ranges */
+static const struct netlink_range_validation ovpn_a_peer_id_range = {
+ .max = 16777215ULL,
+};
+
+static const struct netlink_range_validation ovpn_a_keyconf_peer_id_range = {
+ .max = 16777215ULL,
+};
+
+/* Common nested types */
+const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_DIR + 1] = {
+ [OVPN_A_KEYCONF_PEER_ID] = NLA_POLICY_FULL_RANGE(NLA_U32, &ovpn_a_keyconf_peer_id_range),
+ [OVPN_A_KEYCONF_SLOT] = NLA_POLICY_MAX(NLA_U32, 1),
+ [OVPN_A_KEYCONF_KEY_ID] = NLA_POLICY_MAX(NLA_U32, 7),
+ [OVPN_A_KEYCONF_CIPHER_ALG] = NLA_POLICY_MAX(NLA_U32, 2),
+ [OVPN_A_KEYCONF_ENCRYPT_DIR] = NLA_POLICY_NESTED(ovpn_keydir_nl_policy),
+ [OVPN_A_KEYCONF_DECRYPT_DIR] = NLA_POLICY_NESTED(ovpn_keydir_nl_policy),
+};
+
+const struct nla_policy ovpn_keydir_nl_policy[OVPN_A_KEYDIR_NONCE_TAIL + 1] = {
+ [OVPN_A_KEYDIR_CIPHER_KEY] = NLA_POLICY_MAX_LEN(256),
+ [OVPN_A_KEYDIR_NONCE_TAIL] = NLA_POLICY_EXACT_LEN(OVPN_NONCE_TAIL_SIZE),
+};
+
+const struct nla_policy ovpn_peer_nl_policy[OVPN_A_PEER_LINK_TX_PACKETS + 1] = {
+ [OVPN_A_PEER_ID] = NLA_POLICY_FULL_RANGE(NLA_U32, &ovpn_a_peer_id_range),
+ [OVPN_A_PEER_REMOTE_IPV4] = { .type = NLA_BE32, },
+ [OVPN_A_PEER_REMOTE_IPV6] = NLA_POLICY_EXACT_LEN(16),
+ [OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID] = { .type = NLA_U32, },
+ [OVPN_A_PEER_REMOTE_PORT] = NLA_POLICY_MIN(NLA_BE16, 1),
+ [OVPN_A_PEER_SOCKET] = { .type = NLA_U32, },
+ [OVPN_A_PEER_SOCKET_NETNSID] = { .type = NLA_S32, },
+ [OVPN_A_PEER_VPN_IPV4] = { .type = NLA_BE32, },
+ [OVPN_A_PEER_VPN_IPV6] = NLA_POLICY_EXACT_LEN(16),
+ [OVPN_A_PEER_LOCAL_IPV4] = { .type = NLA_BE32, },
+ [OVPN_A_PEER_LOCAL_IPV6] = NLA_POLICY_EXACT_LEN(16),
+ [OVPN_A_PEER_LOCAL_PORT] = NLA_POLICY_MIN(NLA_BE16, 1),
+ [OVPN_A_PEER_KEEPALIVE_INTERVAL] = { .type = NLA_U32, },
+ [OVPN_A_PEER_KEEPALIVE_TIMEOUT] = { .type = NLA_U32, },
+ [OVPN_A_PEER_DEL_REASON] = NLA_POLICY_MAX(NLA_U32, 4),
+ [OVPN_A_PEER_VPN_RX_BYTES] = { .type = NLA_UINT, },
+ [OVPN_A_PEER_VPN_TX_BYTES] = { .type = NLA_UINT, },
+ [OVPN_A_PEER_VPN_RX_PACKETS] = { .type = NLA_UINT, },
+ [OVPN_A_PEER_VPN_TX_PACKETS] = { .type = NLA_UINT, },
+ [OVPN_A_PEER_LINK_RX_BYTES] = { .type = NLA_UINT, },
+ [OVPN_A_PEER_LINK_TX_BYTES] = { .type = NLA_UINT, },
+ [OVPN_A_PEER_LINK_RX_PACKETS] = { .type = NLA_U32, },
+ [OVPN_A_PEER_LINK_TX_PACKETS] = { .type = NLA_U32, },
+};
+
+/* OVPN_CMD_PEER_NEW - do */
+static const struct nla_policy ovpn_peer_new_nl_policy[OVPN_A_PEER + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+ [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy),
+};
+
+/* OVPN_CMD_PEER_SET - do */
+static const struct nla_policy ovpn_peer_set_nl_policy[OVPN_A_PEER + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+ [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy),
+};
+
+/* OVPN_CMD_PEER_GET - do */
+static const struct nla_policy ovpn_peer_get_do_nl_policy[OVPN_A_PEER + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+ [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy),
+};
+
+/* OVPN_CMD_PEER_GET - dump */
+static const struct nla_policy ovpn_peer_get_dump_nl_policy[OVPN_A_IFINDEX + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+};
+
+/* OVPN_CMD_PEER_DEL - do */
+static const struct nla_policy ovpn_peer_del_nl_policy[OVPN_A_PEER + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+ [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy),
+};
+
+/* OVPN_CMD_KEY_NEW - do */
+static const struct nla_policy ovpn_key_new_nl_policy[OVPN_A_KEYCONF + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+ [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_nl_policy),
+};
+
+/* OVPN_CMD_KEY_GET - do */
+static const struct nla_policy ovpn_key_get_nl_policy[OVPN_A_KEYCONF + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+ [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_nl_policy),
+};
+
+/* OVPN_CMD_KEY_SWAP - do */
+static const struct nla_policy ovpn_key_swap_nl_policy[OVPN_A_KEYCONF + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+ [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_nl_policy),
+};
+
+/* OVPN_CMD_KEY_DEL - do */
+static const struct nla_policy ovpn_key_del_nl_policy[OVPN_A_KEYCONF + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+ [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_nl_policy),
+};
+
+/* Ops table for ovpn */
+static const struct genl_split_ops ovpn_nl_ops[] = {
+ {
+ .cmd = OVPN_CMD_PEER_NEW,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_peer_new_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_peer_new_nl_policy,
+ .maxattr = OVPN_A_PEER,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_PEER_SET,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_peer_set_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_peer_set_nl_policy,
+ .maxattr = OVPN_A_PEER,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_PEER_GET,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_peer_get_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_peer_get_do_nl_policy,
+ .maxattr = OVPN_A_PEER,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_PEER_GET,
+ .dumpit = ovpn_nl_peer_get_dumpit,
+ .policy = ovpn_peer_get_dump_nl_policy,
+ .maxattr = OVPN_A_IFINDEX,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DUMP,
+ },
+ {
+ .cmd = OVPN_CMD_PEER_DEL,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_peer_del_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_peer_del_nl_policy,
+ .maxattr = OVPN_A_PEER,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_KEY_NEW,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_key_new_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_key_new_nl_policy,
+ .maxattr = OVPN_A_KEYCONF,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_KEY_GET,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_key_get_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_key_get_nl_policy,
+ .maxattr = OVPN_A_KEYCONF,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_KEY_SWAP,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_key_swap_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_key_swap_nl_policy,
+ .maxattr = OVPN_A_KEYCONF,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_KEY_DEL,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_key_del_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_key_del_nl_policy,
+ .maxattr = OVPN_A_KEYCONF,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+};
+
+static const struct genl_multicast_group ovpn_nl_mcgrps[] = {
+ [OVPN_NLGRP_PEERS] = { "peers", },
+};
+
+struct genl_family ovpn_nl_family __ro_after_init = {
+ .name = OVPN_FAMILY_NAME,
+ .version = OVPN_FAMILY_VERSION,
+ .netnsok = true,
+ .parallel_ops = true,
+ .module = THIS_MODULE,
+ .split_ops = ovpn_nl_ops,
+ .n_split_ops = ARRAY_SIZE(ovpn_nl_ops),
+ .mcgrps = ovpn_nl_mcgrps,
+ .n_mcgrps = ARRAY_SIZE(ovpn_nl_mcgrps),
+};
diff --git a/drivers/net/ovpn/netlink-gen.h b/drivers/net/ovpn/netlink-gen.h
new file mode 100644
index 0000000000000000000000000000000000000000..66a4e4a0a055b4477b67801ded825e9ec068b0e6
--- /dev/null
+++ b/drivers/net/ovpn/netlink-gen.h
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */
+/* Do not edit directly, auto-generated from: */
+/* Documentation/netlink/specs/ovpn.yaml */
+/* YNL-GEN kernel header */
+
+#ifndef _LINUX_OVPN_GEN_H
+#define _LINUX_OVPN_GEN_H
+
+#include <net/netlink.h>
+#include <net/genetlink.h>
+
+#include <uapi/linux/ovpn.h>
+
+/* Common nested types */
+extern const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_DIR + 1];
+extern const struct nla_policy ovpn_keydir_nl_policy[OVPN_A_KEYDIR_NONCE_TAIL + 1];
+extern const struct nla_policy ovpn_peer_nl_policy[OVPN_A_PEER_LINK_TX_PACKETS + 1];
+
+int ovpn_nl_pre_doit(const struct genl_split_ops *ops, struct sk_buff *skb,
+ struct genl_info *info);
+void
+ovpn_nl_post_doit(const struct genl_split_ops *ops, struct sk_buff *skb,
+ struct genl_info *info);
+
+int ovpn_nl_peer_new_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_peer_set_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_peer_get_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_peer_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb);
+int ovpn_nl_peer_del_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_key_get_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_key_swap_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info);
+
+enum {
+ OVPN_NLGRP_PEERS,
+};
+
+extern struct genl_family ovpn_nl_family;
+
+#endif /* _LINUX_OVPN_GEN_H */
diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c
new file mode 100644
index 0000000000000000000000000000000000000000..8d267d4c82283d9b5f989478102086ce385195d5
--- /dev/null
+++ b/drivers/net/ovpn/netlink.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/netdevice.h>
+#include <net/genetlink.h>
+
+#include <uapi/linux/ovpn.h>
+
+#include "ovpnpriv.h"
+#include "main.h"
+#include "netlink.h"
+#include "netlink-gen.h"
+
+MODULE_ALIAS_GENL_FAMILY(OVPN_FAMILY_NAME);
+
+/**
+ * ovpn_get_dev_from_attrs - retrieve the ovpn private data from the netdevice
+ * a netlink message is targeting
+ * @net: network namespace where to look for the interface
+ * @info: generic netlink info from the user request
+ * @tracker: tracker object to be used for the netdev reference acquisition
+ *
+ * Return: the ovpn private data, if found, or an error otherwise
+ */
+static struct ovpn_priv *
+ovpn_get_dev_from_attrs(struct net *net, const struct genl_info *info,
+ netdevice_tracker *tracker)
+{
+ struct ovpn_priv *ovpn;
+ struct net_device *dev;
+ int ifindex;
+
+ if (GENL_REQ_ATTR_CHECK(info, OVPN_A_IFINDEX))
+ return ERR_PTR(-EINVAL);
+
+ ifindex = nla_get_u32(info->attrs[OVPN_A_IFINDEX]);
+
+ rcu_read_lock();
+ dev = dev_get_by_index_rcu(net, ifindex);
+ if (!dev) {
+ rcu_read_unlock();
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "ifindex does not match any interface");
+ return ERR_PTR(-ENODEV);
+ }
+
+ if (!ovpn_dev_is_valid(dev)) {
+ rcu_read_unlock();
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "specified interface is not ovpn");
+ NL_SET_BAD_ATTR(info->extack, info->attrs[OVPN_A_IFINDEX]);
+ return ERR_PTR(-EINVAL);
+ }
+
+ ovpn = netdev_priv(dev);
+ netdev_hold(dev, tracker, GFP_ATOMIC);
+ rcu_read_unlock();
+
+ return ovpn;
+}
+
+int ovpn_nl_pre_doit(const struct genl_split_ops *ops, struct sk_buff *skb,
+ struct genl_info *info)
+{
+ netdevice_tracker *tracker = (netdevice_tracker *)&info->user_ptr[1];
+ struct ovpn_priv *ovpn = ovpn_get_dev_from_attrs(genl_info_net(info),
+ info, tracker);
+
+ if (IS_ERR(ovpn))
+ return PTR_ERR(ovpn);
+
+ info->user_ptr[0] = ovpn;
+
+ return 0;
+}
+
+void ovpn_nl_post_doit(const struct genl_split_ops *ops, struct sk_buff *skb,
+ struct genl_info *info)
+{
+ netdevice_tracker *tracker = (netdevice_tracker *)&info->user_ptr[1];
+ struct ovpn_priv *ovpn = info->user_ptr[0];
+
+ if (ovpn)
+ netdev_put(ovpn->dev, tracker);
+}
+
+int ovpn_nl_peer_new_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_peer_set_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_peer_get_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_peer_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_peer_del_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_key_get_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_key_swap_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+/**
+ * ovpn_nl_register - perform any needed registration in the NL subsustem
+ *
+ * Return: 0 on success, a negative error code otherwise
+ */
+int __init ovpn_nl_register(void)
+{
+ int ret = genl_register_family(&ovpn_nl_family);
+
+ if (ret) {
+ pr_err("ovpn: genl_register_family failed: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+/**
+ * ovpn_nl_unregister - undo any module wide netlink registration
+ */
+void ovpn_nl_unregister(void)
+{
+ genl_unregister_family(&ovpn_nl_family);
+}
diff --git a/drivers/net/ovpn/netlink.h b/drivers/net/ovpn/netlink.h
new file mode 100644
index 0000000000000000000000000000000000000000..0d6c34e17082cc7c52dd9c5d5ed1e964925b3f4b
--- /dev/null
+++ b/drivers/net/ovpn/netlink.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_NETLINK_H_
+#define _NET_OVPN_NETLINK_H_
+
+int ovpn_nl_register(void);
+void ovpn_nl_unregister(void);
+
+#endif /* _NET_OVPN_NETLINK_H_ */
diff --git a/drivers/net/ovpn/ovpnpriv.h b/drivers/net/ovpn/ovpnpriv.h
new file mode 100644
index 0000000000000000000000000000000000000000..f9322536b06d6baa5524de57cd7d69f5ecbbd194
--- /dev/null
+++ b/drivers/net/ovpn/ovpnpriv.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_OVPNSTRUCT_H_
+#define _NET_OVPN_OVPNSTRUCT_H_
+
+/**
+ * struct ovpn_priv - per ovpn interface state
+ * @dev: the actual netdev representing the tunnel
+ */
+struct ovpn_priv {
+ struct net_device *dev;
+};
+
+#endif /* _NET_OVPN_OVPNSTRUCT_H_ */
diff --git a/include/uapi/linux/ovpn.h b/include/uapi/linux/ovpn.h
new file mode 100644
index 0000000000000000000000000000000000000000..d38757f34acf40a386ff8a515298d164e3b35938
--- /dev/null
+++ b/include/uapi/linux/ovpn.h
@@ -0,0 +1,110 @@
+/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */
+/* Do not edit directly, auto-generated from: */
+/* Documentation/netlink/specs/ovpn.yaml */
+/* YNL-GEN uapi header */
+
+#ifndef _UAPI_LINUX_OVPN_H
+#define _UAPI_LINUX_OVPN_H
+
+#define OVPN_FAMILY_NAME "ovpn"
+#define OVPN_FAMILY_VERSION 1
+
+#define OVPN_NONCE_TAIL_SIZE 8
+
+enum ovpn_cipher_alg {
+ OVPN_CIPHER_ALG_NONE,
+ OVPN_CIPHER_ALG_AES_GCM,
+ OVPN_CIPHER_ALG_CHACHA20_POLY1305,
+};
+
+enum ovpn_del_peer_reason {
+ OVPN_DEL_PEER_REASON_TEARDOWN,
+ OVPN_DEL_PEER_REASON_USERSPACE,
+ OVPN_DEL_PEER_REASON_EXPIRED,
+ OVPN_DEL_PEER_REASON_TRANSPORT_ERROR,
+ OVPN_DEL_PEER_REASON_TRANSPORT_DISCONNECT,
+};
+
+enum ovpn_key_slot {
+ OVPN_KEY_SLOT_PRIMARY,
+ OVPN_KEY_SLOT_SECONDARY,
+};
+
+enum {
+ OVPN_A_PEER_ID = 1,
+ OVPN_A_PEER_REMOTE_IPV4,
+ OVPN_A_PEER_REMOTE_IPV6,
+ OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID,
+ OVPN_A_PEER_REMOTE_PORT,
+ OVPN_A_PEER_SOCKET,
+ OVPN_A_PEER_SOCKET_NETNSID,
+ OVPN_A_PEER_VPN_IPV4,
+ OVPN_A_PEER_VPN_IPV6,
+ OVPN_A_PEER_LOCAL_IPV4,
+ OVPN_A_PEER_LOCAL_IPV6,
+ OVPN_A_PEER_LOCAL_PORT,
+ OVPN_A_PEER_KEEPALIVE_INTERVAL,
+ OVPN_A_PEER_KEEPALIVE_TIMEOUT,
+ OVPN_A_PEER_DEL_REASON,
+ OVPN_A_PEER_VPN_RX_BYTES,
+ OVPN_A_PEER_VPN_TX_BYTES,
+ OVPN_A_PEER_VPN_RX_PACKETS,
+ OVPN_A_PEER_VPN_TX_PACKETS,
+ OVPN_A_PEER_LINK_RX_BYTES,
+ OVPN_A_PEER_LINK_TX_BYTES,
+ OVPN_A_PEER_LINK_RX_PACKETS,
+ OVPN_A_PEER_LINK_TX_PACKETS,
+
+ __OVPN_A_PEER_MAX,
+ OVPN_A_PEER_MAX = (__OVPN_A_PEER_MAX - 1)
+};
+
+enum {
+ OVPN_A_KEYCONF_PEER_ID = 1,
+ OVPN_A_KEYCONF_SLOT,
+ OVPN_A_KEYCONF_KEY_ID,
+ OVPN_A_KEYCONF_CIPHER_ALG,
+ OVPN_A_KEYCONF_ENCRYPT_DIR,
+ OVPN_A_KEYCONF_DECRYPT_DIR,
+
+ __OVPN_A_KEYCONF_MAX,
+ OVPN_A_KEYCONF_MAX = (__OVPN_A_KEYCONF_MAX - 1)
+};
+
+enum {
+ OVPN_A_KEYDIR_CIPHER_KEY = 1,
+ OVPN_A_KEYDIR_NONCE_TAIL,
+
+ __OVPN_A_KEYDIR_MAX,
+ OVPN_A_KEYDIR_MAX = (__OVPN_A_KEYDIR_MAX - 1)
+};
+
+enum {
+ OVPN_A_IFINDEX = 1,
+ OVPN_A_IFNAME,
+ OVPN_A_PEER,
+ OVPN_A_KEYCONF,
+
+ __OVPN_A_MAX,
+ OVPN_A_MAX = (__OVPN_A_MAX - 1)
+};
+
+enum {
+ OVPN_CMD_PEER_NEW = 1,
+ OVPN_CMD_PEER_SET,
+ OVPN_CMD_PEER_GET,
+ OVPN_CMD_PEER_DEL,
+ OVPN_CMD_PEER_DEL_NTF,
+ OVPN_CMD_KEY_NEW,
+ OVPN_CMD_KEY_GET,
+ OVPN_CMD_KEY_SWAP,
+ OVPN_CMD_KEY_SWAP_NTF,
+ OVPN_CMD_KEY_DEL,
+
+ __OVPN_CMD_MAX,
+ OVPN_CMD_MAX = (__OVPN_CMD_MAX - 1)
+};
+
+#define OVPN_MCGRP_PEERS "peers"
+
+#endif /* _UAPI_LINUX_OVPN_H */
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 03/24] ovpn: add basic interface creation/destruction/management routines
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 01/24] net: introduce OpenVPN Data Channel Offload (ovpn) Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 02/24] ovpn: add basic netlink support Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 04/24] ovpn: keep carrier always on for MP interfaces Antonio Quartulli
` (20 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
Add basic infrastructure for handling ovpn interfaces.
Tested-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
Documentation/netlink/specs/rt_link.yaml | 16 +++++
drivers/net/ovpn/Makefile | 1 +
drivers/net/ovpn/io.c | 22 ++++++
drivers/net/ovpn/io.h | 24 +++++++
drivers/net/ovpn/main.c | 114 +++++++++++++++++++++++++++++--
drivers/net/ovpn/ovpnpriv.h | 7 ++
drivers/net/ovpn/proto.h | 38 +++++++++++
include/uapi/linux/if_link.h | 15 ++++
8 files changed, 232 insertions(+), 5 deletions(-)
diff --git a/Documentation/netlink/specs/rt_link.yaml b/Documentation/netlink/specs/rt_link.yaml
index 8b5c0f067328553dde5e29a8aaa25c8e6aed3b42..d604f8752d73a607e987cc516fce0acb2f3a469e 100644
--- a/Documentation/netlink/specs/rt_link.yaml
+++ b/Documentation/netlink/specs/rt_link.yaml
@@ -938,6 +938,12 @@ definitions:
entries:
- name: none
- name: default
+ -
+ name: ovpn-mode
+ type: enum
+ entries:
+ - p2p
+ - mp
attribute-sets:
-
@@ -2269,6 +2275,13 @@ attribute-sets:
-
name: tailroom
type: u16
+ -
+ name: linkinfo-ovpn-attrs
+ attributes:
+ -
+ name: mode
+ type: u8
+ enum: ovpn-mode
sub-messages:
-
@@ -2319,6 +2332,9 @@ sub-messages:
-
value: netkit
attribute-set: linkinfo-netkit-attrs
+ -
+ value: ovpn
+ attribute-set: linkinfo-ovpn-attrs
-
name: linkinfo-member-data-msg
formats:
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
index 75ac62bba02937bc49cb2a0dec5ca3cc31a8ee00..0e5f686672fb5052cee5a2c28797b70859514a7f 100644
--- a/drivers/net/ovpn/Makefile
+++ b/drivers/net/ovpn/Makefile
@@ -8,5 +8,6 @@
obj-$(CONFIG_OVPN) := ovpn.o
ovpn-y += main.o
+ovpn-y += io.o
ovpn-y += netlink.o
ovpn-y += netlink-gen.o
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
new file mode 100644
index 0000000000000000000000000000000000000000..4b71c38165d7adbb1a2d1a64d27a13b7f76cfbfe
--- /dev/null
+++ b/drivers/net/ovpn/io.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+
+#include "io.h"
+
+/* Send user data to the network
+ */
+netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ skb_tx_error(skb);
+ kfree_skb(skb);
+ return NET_XMIT_DROP;
+}
diff --git a/drivers/net/ovpn/io.h b/drivers/net/ovpn/io.h
new file mode 100644
index 0000000000000000000000000000000000000000..afea5f81f5628dcb9afda9a78974bbf6f2101c13
--- /dev/null
+++ b/drivers/net/ovpn/io.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_OVPN_H_
+#define _NET_OVPN_OVPN_H_
+
+/* DATA_V2 header size with AEAD encryption */
+#define OVPN_HEAD_ROOM (OVPN_OPCODE_SIZE + OVPN_NONCE_WIRE_SIZE + \
+ 16 /* AEAD TAG length */ + \
+ max(sizeof(struct udphdr), sizeof(struct tcphdr)) +\
+ max(sizeof(struct ipv6hdr), sizeof(struct iphdr)))
+
+/* max padding required by encryption */
+#define OVPN_MAX_PADDING 16
+
+netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev);
+
+#endif /* _NET_OVPN_OVPN_H_ */
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index 28133e7e15e74b8a4a937ed03f70d9f83d7a14c8..e71183e6f42cd801861caaec9eb0f6828b64cda9 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -10,14 +10,42 @@
#include <linux/genetlink.h>
#include <linux/module.h>
#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
+#include <net/ip.h>
#include <net/rtnetlink.h>
-#include <uapi/linux/ovpn.h>
+#include <uapi/linux/if_arp.h>
#include "ovpnpriv.h"
#include "main.h"
#include "netlink.h"
+#include "io.h"
+#include "proto.h"
+
+static int ovpn_net_open(struct net_device *dev)
+{
+ netif_tx_start_all_queues(dev);
+ return 0;
+}
+
+static int ovpn_net_stop(struct net_device *dev)
+{
+ netif_tx_stop_all_queues(dev);
+ return 0;
+}
static const struct net_device_ops ovpn_netdev_ops = {
+ .ndo_open = ovpn_net_open,
+ .ndo_stop = ovpn_net_stop,
+ .ndo_start_xmit = ovpn_net_xmit,
+};
+
+static const struct device_type ovpn_type = {
+ .name = OVPN_FAMILY_NAME,
+};
+
+static const struct nla_policy ovpn_policy[IFLA_OVPN_MAX + 1] = {
+ [IFLA_OVPN_MODE] = NLA_POLICY_RANGE(NLA_U8, OVPN_MODE_P2P,
+ OVPN_MODE_MP),
};
/**
@@ -31,44 +59,120 @@ bool ovpn_dev_is_valid(const struct net_device *dev)
return dev->netdev_ops == &ovpn_netdev_ops;
}
+static void ovpn_setup(struct net_device *dev)
+{
+ netdev_features_t feat = NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_RXCSUM |
+ NETIF_F_GSO | NETIF_F_GSO_SOFTWARE |
+ NETIF_F_HIGHDMA;
+
+ dev->needs_free_netdev = true;
+
+ dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
+
+ dev->netdev_ops = &ovpn_netdev_ops;
+
+ dev->hard_header_len = 0;
+ dev->addr_len = 0;
+ dev->mtu = ETH_DATA_LEN - OVPN_HEAD_ROOM;
+ dev->min_mtu = IPV4_MIN_MTU;
+ dev->max_mtu = IP_MAX_MTU - OVPN_HEAD_ROOM;
+
+ dev->type = ARPHRD_NONE;
+ dev->flags = IFF_POINTOPOINT | IFF_NOARP;
+ dev->priv_flags |= IFF_NO_QUEUE;
+
+ dev->lltx = true;
+ dev->features |= feat;
+ dev->hw_features |= feat;
+ dev->hw_enc_features |= feat;
+
+ dev->needed_headroom = ALIGN(OVPN_HEAD_ROOM, 4);
+ dev->needed_tailroom = OVPN_MAX_PADDING;
+
+ SET_NETDEV_DEVTYPE(dev, &ovpn_type);
+}
+
static int ovpn_newlink(struct net_device *dev,
struct rtnl_newlink_params *params,
struct netlink_ext_ack *extack)
{
- return -EOPNOTSUPP;
+ struct ovpn_priv *ovpn = netdev_priv(dev);
+ struct nlattr **data = params->data;
+ enum ovpn_mode mode = OVPN_MODE_P2P;
+
+ if (data && data[IFLA_OVPN_MODE]) {
+ mode = nla_get_u8(data[IFLA_OVPN_MODE]);
+ netdev_dbg(dev, "setting device mode: %u\n", mode);
+ }
+
+ ovpn->dev = dev;
+ ovpn->mode = mode;
+
+ /* turn carrier explicitly off after registration, this way state is
+ * clearly defined
+ */
+ netif_carrier_off(dev);
+
+ return register_netdevice(dev);
+}
+
+static int ovpn_fill_info(struct sk_buff *skb, const struct net_device *dev)
+{
+ struct ovpn_priv *ovpn = netdev_priv(dev);
+
+ if (nla_put_u8(skb, IFLA_OVPN_MODE, ovpn->mode))
+ return -EMSGSIZE;
+
+ return 0;
}
static struct rtnl_link_ops ovpn_link_ops = {
.kind = "ovpn",
.netns_refund = false,
+ .priv_size = sizeof(struct ovpn_priv),
+ .setup = ovpn_setup,
+ .policy = ovpn_policy,
+ .maxtype = IFLA_OVPN_MAX,
.newlink = ovpn_newlink,
.dellink = unregister_netdevice_queue,
+ .fill_info = ovpn_fill_info,
};
static int ovpn_netdev_notifier_call(struct notifier_block *nb,
unsigned long state, void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+ struct ovpn_priv *ovpn;
if (!ovpn_dev_is_valid(dev))
return NOTIFY_DONE;
+ ovpn = netdev_priv(dev);
+
switch (state) {
case NETDEV_REGISTER:
- /* add device to internal list for later destruction upon
- * unregistration
- */
+ ovpn->registered = true;
break;
case NETDEV_UNREGISTER:
+ /* twiddle thumbs on netns device moves */
+ if (dev->reg_state != NETREG_UNREGISTERING)
+ break;
+
/* can be delivered multiple times, so check registered flag,
* then destroy the interface
*/
+ if (!ovpn->registered)
+ return NOTIFY_DONE;
+
+ netif_carrier_off(dev);
+ ovpn->registered = false;
break;
case NETDEV_POST_INIT:
case NETDEV_GOING_DOWN:
case NETDEV_DOWN:
case NETDEV_UP:
case NETDEV_PRE_UP:
+ break;
default:
return NOTIFY_DONE;
}
diff --git a/drivers/net/ovpn/ovpnpriv.h b/drivers/net/ovpn/ovpnpriv.h
index f9322536b06d6baa5524de57cd7d69f5ecbbd194..33c2a41edf9b3204e8aebd2679649cb7158f05f2 100644
--- a/drivers/net/ovpn/ovpnpriv.h
+++ b/drivers/net/ovpn/ovpnpriv.h
@@ -10,12 +10,19 @@
#ifndef _NET_OVPN_OVPNSTRUCT_H_
#define _NET_OVPN_OVPNSTRUCT_H_
+#include <uapi/linux/if_link.h>
+#include <uapi/linux/ovpn.h>
+
/**
* struct ovpn_priv - per ovpn interface state
* @dev: the actual netdev representing the tunnel
+ * @registered: whether dev is still registered with netdev or not
+ * @mode: device operation mode (i.e. p2p, mp, ..)
*/
struct ovpn_priv {
struct net_device *dev;
+ bool registered;
+ enum ovpn_mode mode;
};
#endif /* _NET_OVPN_OVPNSTRUCT_H_ */
diff --git a/drivers/net/ovpn/proto.h b/drivers/net/ovpn/proto.h
new file mode 100644
index 0000000000000000000000000000000000000000..5f95a78bebd3702868ffeeab3ea4938e957d568c
--- /dev/null
+++ b/drivers/net/ovpn/proto.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ * James Yonan <james@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_PROTO_H_
+#define _NET_OVPN_PROTO_H_
+
+/* When the OpenVPN protocol is ran in AEAD mode, use
+ * the OpenVPN packet ID as the AEAD nonce:
+ *
+ * 00000005 521c3b01 4308c041
+ * [seq # ] [ nonce_tail ]
+ * [ 12-byte full IV ] -> OVPN_NONCE_SIZE
+ * [4-bytes -> OVPN_NONCE_WIRE_SIZE
+ * on wire]
+ */
+
+/* nonce size (96bits) as required by AEAD ciphers */
+#define OVPN_NONCE_SIZE 12
+/* last 8 bytes of AEAD nonce: provided by userspace and usually derived
+ * from key material generated during TLS handshake
+ */
+#define OVPN_NONCE_TAIL_SIZE 8
+
+/* OpenVPN nonce size reduced by 8-byte nonce tail -- this is the
+ * size of the AEAD Associated Data (AD) sent over the wire
+ * and is normally the head of the IV
+ */
+#define OVPN_NONCE_WIRE_SIZE (OVPN_NONCE_SIZE - OVPN_NONCE_TAIL_SIZE)
+
+#define OVPN_OPCODE_SIZE 4 /* DATA_V2 opcode size */
+
+#endif /* _NET_OVPN_PROTO_H_ */
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 3b586fb0bc4cddf6655d48ba7b31ab1c200532d6..cfae55af7a36b9581cd74c50e15fbc992501265d 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -1985,4 +1985,19 @@ enum {
#define IFLA_DSA_MAX (__IFLA_DSA_MAX - 1)
+/* OVPN section */
+
+enum ovpn_mode {
+ OVPN_MODE_P2P,
+ OVPN_MODE_MP,
+};
+
+enum {
+ IFLA_OVPN_UNSPEC,
+ IFLA_OVPN_MODE,
+ __IFLA_OVPN_MAX,
+};
+
+#define IFLA_OVPN_MAX (__IFLA_OVPN_MAX - 1)
+
#endif /* _UAPI_LINUX_IF_LINK_H */
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 04/24] ovpn: keep carrier always on for MP interfaces
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (2 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 03/24] ovpn: add basic interface creation/destruction/management routines Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 05/24] ovpn: introduce the ovpn_peer object Antonio Quartulli
` (19 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
An ovpn interface configured in MP mode will keep carrier always
on and let the user decide when to bring it administratively up and
down.
This way a MP node (i.e. a server) will keep its interface always
up and running, even when no peer is connected.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/main.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index e71183e6f42cd801861caaec9eb0f6828b64cda9..c5e75108b8da5eabde25426c6d6668fb14491986 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -23,6 +23,15 @@
static int ovpn_net_open(struct net_device *dev)
{
+ struct ovpn_priv *ovpn = netdev_priv(dev);
+
+ /* carrier for P2P interfaces is switched on and off when
+ * the peer is added or deleted.
+ *
+ * in case of P2MP interfaces we just keep the carrier always on
+ */
+ if (ovpn->mode == OVPN_MODE_MP)
+ netif_carrier_on(dev);
netif_tx_start_all_queues(dev);
return 0;
}
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 05/24] ovpn: introduce the ovpn_peer object
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (3 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 04/24] ovpn: keep carrier always on for MP interfaces Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 06/24] ovpn: introduce the ovpn_socket object Antonio Quartulli
` (18 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
An ovpn_peer object holds the whole status of a remote peer
(regardless whether it is a server or a client).
This includes status for crypto, tx/rx buffers, napi, etc.
Only support for one peer is introduced (P2P mode).
Multi peer support is introduced with a later patch.
Along with the ovpn_peer, also the ovpn_bind object is introcued
as the two are strictly related.
An ovpn_bind object wraps a sockaddr representing the local
coordinates being used to talk to a specific peer.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/Kconfig | 1 +
drivers/net/ovpn/Makefile | 2 +
drivers/net/ovpn/bind.c | 58 +++++++
drivers/net/ovpn/bind.h | 101 +++++++++++
drivers/net/ovpn/main.c | 12 ++
drivers/net/ovpn/ovpnpriv.h | 4 +
drivers/net/ovpn/peer.c | 411 ++++++++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/peer.h | 80 +++++++++
8 files changed, 669 insertions(+)
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 2ace5e27c37ed3bad2e0000775cd172cb6de3225..dfd1ad96230317c4118b63c9c98d0a631f6cbb21 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -119,6 +119,7 @@ config OVPN
tristate "OpenVPN data channel offload"
depends on NET && INET
depends on IPV6 || !IPV6
+ select DST_CACHE
help
This module enhances the performance of the OpenVPN userspace software
by offloading the data channel processing to kernelspace.
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
index 0e5f686672fb5052cee5a2c28797b70859514a7f..618328ae338861b9764b42485df71ebd0fc1fe90 100644
--- a/drivers/net/ovpn/Makefile
+++ b/drivers/net/ovpn/Makefile
@@ -7,7 +7,9 @@
# Author: Antonio Quartulli <antonio@openvpn.net>
obj-$(CONFIG_OVPN) := ovpn.o
+ovpn-y += bind.o
ovpn-y += main.o
ovpn-y += io.o
ovpn-y += netlink.o
ovpn-y += netlink-gen.o
+ovpn-y += peer.o
diff --git a/drivers/net/ovpn/bind.c b/drivers/net/ovpn/bind.c
new file mode 100644
index 0000000000000000000000000000000000000000..d4a1aeed12c99c71eaf5e8e9fc9c0fe61af6aaac
--- /dev/null
+++ b/drivers/net/ovpn/bind.c
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2012-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/netdevice.h>
+#include <linux/socket.h>
+
+#include "ovpnpriv.h"
+#include "bind.h"
+#include "peer.h"
+
+/**
+ * ovpn_bind_from_sockaddr - retrieve binding matching sockaddr
+ * @ss: the sockaddr to match
+ *
+ * Return: the bind matching the passed sockaddr if found, NULL otherwise
+ */
+struct ovpn_bind *ovpn_bind_from_sockaddr(const struct sockaddr_storage *ss)
+{
+ struct ovpn_bind *bind;
+ size_t sa_len;
+
+ if (ss->ss_family == AF_INET)
+ sa_len = sizeof(struct sockaddr_in);
+ else if (ss->ss_family == AF_INET6)
+ sa_len = sizeof(struct sockaddr_in6);
+ else
+ return ERR_PTR(-EAFNOSUPPORT);
+
+ bind = kzalloc(sizeof(*bind), GFP_ATOMIC);
+ if (unlikely(!bind))
+ return ERR_PTR(-ENOMEM);
+
+ memcpy(&bind->remote, ss, sa_len);
+
+ return bind;
+}
+
+/**
+ * ovpn_bind_reset - assign new binding to peer
+ * @peer: the peer whose binding has to be replaced
+ * @new: the new bind to assign
+ */
+void ovpn_bind_reset(struct ovpn_peer *peer, struct ovpn_bind *new)
+{
+ struct ovpn_bind *old;
+
+ spin_lock_bh(&peer->lock);
+ old = rcu_replace_pointer(peer->bind, new, true);
+ spin_unlock_bh(&peer->lock);
+
+ kfree_rcu(old, rcu);
+}
diff --git a/drivers/net/ovpn/bind.h b/drivers/net/ovpn/bind.h
new file mode 100644
index 0000000000000000000000000000000000000000..4e0b8398bfd9ed60ecb01c777c61a5e6841d7dec
--- /dev/null
+++ b/drivers/net/ovpn/bind.h
@@ -0,0 +1,101 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2012-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_OVPNBIND_H_
+#define _NET_OVPN_OVPNBIND_H_
+
+#include <net/ip.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/rcupdate.h>
+#include <linux/skbuff.h>
+#include <linux/spinlock.h>
+
+struct ovpn_peer;
+
+/**
+ * union ovpn_sockaddr - basic transport layer address
+ * @in4: IPv4 address
+ * @in6: IPv6 address
+ */
+union ovpn_sockaddr {
+ struct sockaddr_in in4;
+ struct sockaddr_in6 in6;
+};
+
+/**
+ * struct ovpn_bind - remote peer binding
+ * @remote: the remote peer sockaddress
+ * @local: local endpoint used to talk to the peer
+ * @local.ipv4: local IPv4 used to talk to the peer
+ * @local.ipv6: local IPv6 used to talk to the peer
+ * @rcu: used to schedule RCU cleanup job
+ */
+struct ovpn_bind {
+ union ovpn_sockaddr remote; /* remote sockaddr */
+
+ union {
+ struct in_addr ipv4;
+ struct in6_addr ipv6;
+ } local;
+
+ struct rcu_head rcu;
+};
+
+/**
+ * ovpn_bind_skb_src_match - match packet source with binding
+ * @bind: the binding to match
+ * @skb: the packet to match
+ *
+ * Return: true if the packet source matches the remote peer sockaddr
+ * in the binding
+ */
+static inline bool ovpn_bind_skb_src_match(const struct ovpn_bind *bind,
+ const struct sk_buff *skb)
+{
+ const union ovpn_sockaddr *remote;
+
+ if (unlikely(!bind))
+ return false;
+
+ remote = &bind->remote;
+
+ switch (skb->protocol) {
+ case htons(ETH_P_IP):
+ if (unlikely(remote->in4.sin_family != AF_INET))
+ return false;
+
+ if (unlikely(remote->in4.sin_addr.s_addr != ip_hdr(skb)->saddr))
+ return false;
+
+ if (unlikely(remote->in4.sin_port != udp_hdr(skb)->source))
+ return false;
+ break;
+ case htons(ETH_P_IPV6):
+ if (unlikely(remote->in6.sin6_family != AF_INET6))
+ return false;
+
+ if (unlikely(!ipv6_addr_equal(&remote->in6.sin6_addr,
+ &ipv6_hdr(skb)->saddr)))
+ return false;
+
+ if (unlikely(remote->in6.sin6_port != udp_hdr(skb)->source))
+ return false;
+ break;
+ default:
+ return false;
+ }
+
+ return true;
+}
+
+struct ovpn_bind *ovpn_bind_from_sockaddr(const struct sockaddr_storage *sa);
+void ovpn_bind_reset(struct ovpn_peer *peer, struct ovpn_bind *bind);
+
+#endif /* _NET_OVPN_OVPNBIND_H_ */
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index c5e75108b8da5eabde25426c6d6668fb14491986..3c72b80095a0ed8f2f2064fdfa556f750f1c7061 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -19,8 +19,14 @@
#include "main.h"
#include "netlink.h"
#include "io.h"
+#include "peer.h"
#include "proto.h"
+static int ovpn_net_init(struct net_device *dev)
+{
+ return 0;
+}
+
static int ovpn_net_open(struct net_device *dev)
{
struct ovpn_priv *ovpn = netdev_priv(dev);
@@ -43,6 +49,7 @@ static int ovpn_net_stop(struct net_device *dev)
}
static const struct net_device_ops ovpn_netdev_ops = {
+ .ndo_init = ovpn_net_init,
.ndo_open = ovpn_net_open,
.ndo_stop = ovpn_net_stop,
.ndo_start_xmit = ovpn_net_xmit,
@@ -116,6 +123,7 @@ static int ovpn_newlink(struct net_device *dev,
ovpn->dev = dev;
ovpn->mode = mode;
+ spin_lock_init(&ovpn->lock);
/* turn carrier explicitly off after registration, this way state is
* clearly defined
@@ -175,6 +183,10 @@ static int ovpn_netdev_notifier_call(struct notifier_block *nb,
netif_carrier_off(dev);
ovpn->registered = false;
+
+ if (ovpn->mode == OVPN_MODE_P2P)
+ ovpn_peer_release_p2p(ovpn,
+ OVPN_DEL_PEER_REASON_TEARDOWN);
break;
case NETDEV_POST_INIT:
case NETDEV_GOING_DOWN:
diff --git a/drivers/net/ovpn/ovpnpriv.h b/drivers/net/ovpn/ovpnpriv.h
index 33c2a41edf9b3204e8aebd2679649cb7158f05f2..fae2682b424b03222a5ce881a4a1b4518a7ff311 100644
--- a/drivers/net/ovpn/ovpnpriv.h
+++ b/drivers/net/ovpn/ovpnpriv.h
@@ -18,11 +18,15 @@
* @dev: the actual netdev representing the tunnel
* @registered: whether dev is still registered with netdev or not
* @mode: device operation mode (i.e. p2p, mp, ..)
+ * @lock: protect this object
+ * @peer: in P2P mode, this is the only remote peer
*/
struct ovpn_priv {
struct net_device *dev;
bool registered;
enum ovpn_mode mode;
+ spinlock_t lock; /* protect writing to the ovpn_priv object */
+ struct ovpn_peer __rcu *peer;
};
#endif /* _NET_OVPN_OVPNSTRUCT_H_ */
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
new file mode 100644
index 0000000000000000000000000000000000000000..338069c99248f42b0c4aeb44b2b9d3a35f8bebeb
--- /dev/null
+++ b/drivers/net/ovpn/peer.c
@@ -0,0 +1,411 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/skbuff.h>
+#include <linux/list.h>
+
+#include "ovpnpriv.h"
+#include "bind.h"
+#include "io.h"
+#include "main.h"
+#include "netlink.h"
+#include "peer.h"
+
+static void unlock_ovpn(struct ovpn_priv *ovpn,
+ struct llist_head *release_list)
+ __releases(&ovpn->lock)
+{
+ struct ovpn_peer *peer;
+
+ spin_unlock_bh(&ovpn->lock);
+
+ llist_for_each_entry(peer, release_list->first, release_entry)
+ ovpn_peer_put(peer);
+}
+
+/**
+ * ovpn_peer_new - allocate and initialize a new peer object
+ * @ovpn: the openvpn instance inside which the peer should be created
+ * @id: the ID assigned to this peer
+ *
+ * Return: a pointer to the new peer on success or an error code otherwise
+ */
+struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id)
+{
+ struct ovpn_peer *peer;
+ int ret;
+
+ /* alloc and init peer object */
+ peer = kzalloc(sizeof(*peer), GFP_KERNEL);
+ if (!peer)
+ return ERR_PTR(-ENOMEM);
+
+ peer->id = id;
+ peer->ovpn = ovpn;
+
+ peer->vpn_addrs.ipv4.s_addr = htonl(INADDR_ANY);
+ peer->vpn_addrs.ipv6 = in6addr_any;
+
+ RCU_INIT_POINTER(peer->bind, NULL);
+ spin_lock_init(&peer->lock);
+ kref_init(&peer->refcount);
+
+ ret = dst_cache_init(&peer->dst_cache, GFP_KERNEL);
+ if (ret < 0) {
+ netdev_err(ovpn->dev,
+ "cannot initialize dst cache for peer %u\n",
+ peer->id);
+ kfree(peer);
+ return ERR_PTR(ret);
+ }
+
+ netdev_hold(ovpn->dev, &peer->dev_tracker, GFP_KERNEL);
+
+ return peer;
+}
+
+/**
+ * ovpn_peer_release_rcu - RCU callback performing last peer release steps
+ * @head: RCU member of the ovpn_peer
+ */
+static void ovpn_peer_release_rcu(struct rcu_head *head)
+{
+ struct ovpn_peer *peer = container_of(head, struct ovpn_peer, rcu);
+
+ /* this call will immediately free the dst_cache, therefore we
+ * perform it in the RCU callback, when all contexts are done
+ */
+ dst_cache_destroy(&peer->dst_cache);
+ kfree(peer);
+}
+
+/**
+ * ovpn_peer_release - release peer private members
+ * @peer: the peer to release
+ */
+static void ovpn_peer_release(struct ovpn_peer *peer)
+{
+ ovpn_bind_reset(peer, NULL);
+ call_rcu(&peer->rcu, ovpn_peer_release_rcu);
+ netdev_put(peer->ovpn->dev, &peer->dev_tracker);
+}
+
+/**
+ * ovpn_peer_release_kref - callback for kref_put
+ * @kref: the kref object belonging to the peer
+ */
+void ovpn_peer_release_kref(struct kref *kref)
+{
+ struct ovpn_peer *peer = container_of(kref, struct ovpn_peer, refcount);
+
+ ovpn_peer_release(peer);
+}
+
+/**
+ * ovpn_peer_skb_to_sockaddr - fill sockaddr with skb source address
+ * @skb: the packet to extract data from
+ * @ss: the sockaddr to fill
+ *
+ * Return: sockaddr length on success or -1 otherwise
+ */
+static int ovpn_peer_skb_to_sockaddr(struct sk_buff *skb,
+ struct sockaddr_storage *ss)
+{
+ struct sockaddr_in6 *sa6;
+ struct sockaddr_in *sa4;
+
+ switch (skb->protocol) {
+ case htons(ETH_P_IP):
+ sa4 = (struct sockaddr_in *)ss;
+ sa4->sin_family = AF_INET;
+ sa4->sin_addr.s_addr = ip_hdr(skb)->saddr;
+ sa4->sin_port = udp_hdr(skb)->source;
+ return sizeof(*sa4);
+ case htons(ETH_P_IPV6):
+ sa6 = (struct sockaddr_in6 *)ss;
+ sa6->sin6_family = AF_INET6;
+ sa6->sin6_addr = ipv6_hdr(skb)->saddr;
+ sa6->sin6_port = udp_hdr(skb)->source;
+ return sizeof(*sa6);
+ }
+
+ return -1;
+}
+
+/**
+ * ovpn_peer_transp_match - check if sockaddr and peer binding match
+ * @peer: the peer to get the binding from
+ * @ss: the sockaddr to match
+ *
+ * Return: true if sockaddr and binding match or false otherwise
+ */
+static bool ovpn_peer_transp_match(const struct ovpn_peer *peer,
+ const struct sockaddr_storage *ss)
+{
+ struct ovpn_bind *bind = rcu_dereference(peer->bind);
+ struct sockaddr_in6 *sa6;
+ struct sockaddr_in *sa4;
+
+ if (unlikely(!bind))
+ return false;
+
+ if (ss->ss_family != bind->remote.in4.sin_family)
+ return false;
+
+ switch (ss->ss_family) {
+ case AF_INET:
+ sa4 = (struct sockaddr_in *)ss;
+ if (sa4->sin_addr.s_addr != bind->remote.in4.sin_addr.s_addr)
+ return false;
+ if (sa4->sin_port != bind->remote.in4.sin_port)
+ return false;
+ break;
+ case AF_INET6:
+ sa6 = (struct sockaddr_in6 *)ss;
+ if (!ipv6_addr_equal(&sa6->sin6_addr,
+ &bind->remote.in6.sin6_addr))
+ return false;
+ if (sa6->sin6_port != bind->remote.in6.sin6_port)
+ return false;
+ break;
+ default:
+ return false;
+ }
+
+ return true;
+}
+
+/**
+ * ovpn_peer_get_by_transp_addr_p2p - get peer by transport address in a P2P
+ * instance
+ * @ovpn: the openvpn instance to search
+ * @ss: the transport socket address
+ *
+ * Return: the peer if found or NULL otherwise
+ */
+static struct ovpn_peer *
+ovpn_peer_get_by_transp_addr_p2p(struct ovpn_priv *ovpn,
+ struct sockaddr_storage *ss)
+{
+ struct ovpn_peer *tmp, *peer = NULL;
+
+ rcu_read_lock();
+ tmp = rcu_dereference(ovpn->peer);
+ if (likely(tmp && ovpn_peer_transp_match(tmp, ss) &&
+ ovpn_peer_hold(tmp)))
+ peer = tmp;
+ rcu_read_unlock();
+
+ return peer;
+}
+
+/**
+ * ovpn_peer_get_by_transp_addr - retrieve peer by transport address
+ * @ovpn: the openvpn instance to search
+ * @skb: the skb to retrieve the source transport address from
+ *
+ * Return: a pointer to the peer if found or NULL otherwise
+ */
+struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_priv *ovpn,
+ struct sk_buff *skb)
+{
+ struct ovpn_peer *peer = NULL;
+ struct sockaddr_storage ss = { 0 };
+
+ if (unlikely(!ovpn_peer_skb_to_sockaddr(skb, &ss)))
+ return NULL;
+
+ if (ovpn->mode == OVPN_MODE_P2P)
+ peer = ovpn_peer_get_by_transp_addr_p2p(ovpn, &ss);
+
+ return peer;
+}
+
+/**
+ * ovpn_peer_get_by_id_p2p - get peer by ID in a P2P instance
+ * @ovpn: the openvpn instance to search
+ * @peer_id: the ID of the peer to find
+ *
+ * Return: the peer if found or NULL otherwise
+ */
+static struct ovpn_peer *ovpn_peer_get_by_id_p2p(struct ovpn_priv *ovpn,
+ u32 peer_id)
+{
+ struct ovpn_peer *tmp, *peer = NULL;
+
+ rcu_read_lock();
+ tmp = rcu_dereference(ovpn->peer);
+ if (likely(tmp && tmp->id == peer_id && ovpn_peer_hold(tmp)))
+ peer = tmp;
+ rcu_read_unlock();
+
+ return peer;
+}
+
+/**
+ * ovpn_peer_get_by_id - retrieve peer by ID
+ * @ovpn: the openvpn instance to search
+ * @peer_id: the unique peer identifier to match
+ *
+ * Return: a pointer to the peer if found or NULL otherwise
+ */
+struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_priv *ovpn, u32 peer_id)
+{
+ struct ovpn_peer *peer = NULL;
+
+ if (ovpn->mode == OVPN_MODE_P2P)
+ peer = ovpn_peer_get_by_id_p2p(ovpn, peer_id);
+
+ return peer;
+}
+
+static void ovpn_peer_remove(struct ovpn_peer *peer,
+ enum ovpn_del_peer_reason reason,
+ struct llist_head *release_list)
+{
+ switch (peer->ovpn->mode) {
+ case OVPN_MODE_P2P:
+ /* prevent double remove */
+ if (peer != rcu_access_pointer(peer->ovpn->peer))
+ return;
+
+ RCU_INIT_POINTER(peer->ovpn->peer, NULL);
+ /* in P2P mode the carrier is switched off when the peer is
+ * deleted so that third party protocols can react accordingly
+ */
+ netif_carrier_off(peer->ovpn->dev);
+ break;
+ default:
+ return;
+ }
+
+ peer->delete_reason = reason;
+
+ /* append to provided list for later socket release and ref drop */
+ llist_add(&peer->release_entry, release_list);
+}
+
+/**
+ * ovpn_peer_add_p2p - add peer to related tables in a P2P instance
+ * @ovpn: the instance to add the peer to
+ * @peer: the peer to add
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+static int ovpn_peer_add_p2p(struct ovpn_priv *ovpn, struct ovpn_peer *peer)
+{
+ LLIST_HEAD(release_list);
+ struct ovpn_peer *tmp;
+
+ spin_lock_bh(&ovpn->lock);
+ /* in p2p mode it is possible to have a single peer only, therefore the
+ * old one is released and substituted by the new one
+ */
+ tmp = rcu_dereference_protected(ovpn->peer,
+ lockdep_is_held(&ovpn->lock));
+ if (tmp)
+ ovpn_peer_remove(tmp, OVPN_DEL_PEER_REASON_TEARDOWN,
+ &release_list);
+
+ rcu_assign_pointer(ovpn->peer, peer);
+ /* in P2P mode the carrier is switched on when the peer is added */
+ netif_carrier_on(ovpn->dev);
+ unlock_ovpn(ovpn, &release_list);
+
+ return 0;
+}
+
+/**
+ * ovpn_peer_add - add peer to the related tables
+ * @ovpn: the openvpn instance the peer belongs to
+ * @peer: the peer object to add
+ *
+ * Assume refcounter was increased by caller
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+int ovpn_peer_add(struct ovpn_priv *ovpn, struct ovpn_peer *peer)
+{
+ switch (ovpn->mode) {
+ case OVPN_MODE_P2P:
+ return ovpn_peer_add_p2p(ovpn, peer);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+/**
+ * ovpn_peer_del_p2p - delete peer from related tables in a P2P instance
+ * @peer: the peer to delete
+ * @reason: reason why the peer was deleted (sent to userspace)
+ * @release_list: list where delete peer should be appended
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+static int ovpn_peer_del_p2p(struct ovpn_peer *peer,
+ enum ovpn_del_peer_reason reason,
+ struct llist_head *release_list)
+{
+ struct ovpn_peer *tmp;
+
+ lockdep_assert_held(&peer->ovpn->lock);
+
+ tmp = rcu_dereference_protected(peer->ovpn->peer,
+ lockdep_is_held(&peer->ovpn->lock));
+ if (tmp != peer)
+ return -ENOENT;
+
+ ovpn_peer_remove(peer, reason, release_list);
+
+ return 0;
+}
+
+/**
+ * ovpn_peer_del - delete peer from related tables
+ * @peer: the peer object to delete
+ * @reason: reason for deleting peer (will be sent to userspace)
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason)
+{
+ LLIST_HEAD(release_list);
+ int ret = -EOPNOTSUPP;
+
+ spin_lock_bh(&peer->ovpn->lock);
+ switch (peer->ovpn->mode) {
+ case OVPN_MODE_P2P:
+ ret = ovpn_peer_del_p2p(peer, reason, &release_list);
+ break;
+ default:
+ break;
+ }
+ unlock_ovpn(peer->ovpn, &release_list);
+
+ return ret;
+}
+
+/**
+ * ovpn_peer_release_p2p - release peer upon P2P device teardown
+ * @ovpn: the instance being torn down
+ * @reason: the reason for releasing the peer
+ */
+void ovpn_peer_release_p2p(struct ovpn_priv *ovpn,
+ enum ovpn_del_peer_reason reason)
+{
+ LLIST_HEAD(release_list);
+ struct ovpn_peer *peer;
+
+ spin_lock_bh(&ovpn->lock);
+ peer = rcu_dereference_protected(ovpn->peer,
+ lockdep_is_held(&ovpn->lock));
+ if (peer)
+ ovpn_peer_remove(peer, reason, &release_list);
+ unlock_ovpn(ovpn, &release_list);
+}
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
new file mode 100644
index 0000000000000000000000000000000000000000..fd2e7625990a73f61bf5bb4c051929828d9996bd
--- /dev/null
+++ b/drivers/net/ovpn/peer.h
@@ -0,0 +1,80 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_OVPNPEER_H_
+#define _NET_OVPN_OVPNPEER_H_
+
+#include <net/dst_cache.h>
+
+/**
+ * struct ovpn_peer - the main remote peer object
+ * @ovpn: main openvpn instance this peer belongs to
+ * @dev_tracker: reference tracker for associated dev
+ * @id: unique identifier
+ * @vpn_addrs: IP addresses assigned over the tunnel
+ * @vpn_addrs.ipv4: IPv4 assigned to peer on the tunnel
+ * @vpn_addrs.ipv6: IPv6 assigned to peer on the tunnel
+ * @dst_cache: cache for dst_entry used to send to peer
+ * @bind: remote peer binding
+ * @delete_reason: why peer was deleted (i.e. timeout, transport error, ..)
+ * @lock: protects binding to peer (bind)
+ * @refcount: reference counter
+ * @rcu: used to free peer in an RCU safe way
+ * @release_entry: entry for the socket release list
+ */
+struct ovpn_peer {
+ struct ovpn_priv *ovpn;
+ netdevice_tracker dev_tracker;
+ u32 id;
+ struct {
+ struct in_addr ipv4;
+ struct in6_addr ipv6;
+ } vpn_addrs;
+ struct dst_cache dst_cache;
+ struct ovpn_bind __rcu *bind;
+ enum ovpn_del_peer_reason delete_reason;
+ spinlock_t lock; /* protects bind */
+ struct kref refcount;
+ struct rcu_head rcu;
+ struct llist_node release_entry;
+};
+
+/**
+ * ovpn_peer_hold - increase reference counter
+ * @peer: the peer whose counter should be increased
+ *
+ * Return: true if the counter was increased or false if it was zero already
+ */
+static inline bool ovpn_peer_hold(struct ovpn_peer *peer)
+{
+ return kref_get_unless_zero(&peer->refcount);
+}
+
+void ovpn_peer_release_kref(struct kref *kref);
+
+/**
+ * ovpn_peer_put - decrease reference counter
+ * @peer: the peer whose counter should be decreased
+ */
+static inline void ovpn_peer_put(struct ovpn_peer *peer)
+{
+ kref_put(&peer->refcount, ovpn_peer_release_kref);
+}
+
+struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id);
+int ovpn_peer_add(struct ovpn_priv *ovpn, struct ovpn_peer *peer);
+int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason);
+void ovpn_peer_release_p2p(struct ovpn_priv *ovpn,
+ enum ovpn_del_peer_reason reason);
+
+struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_priv *ovpn,
+ struct sk_buff *skb);
+struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_priv *ovpn, u32 peer_id);
+
+#endif /* _NET_OVPN_OVPNPEER_H_ */
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 06/24] ovpn: introduce the ovpn_socket object
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (4 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 05/24] ovpn: introduce the ovpn_peer object Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 07/24] ovpn: implement basic TX path (UDP) Antonio Quartulli
` (17 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang,
willemdebruijn.kernel
This specific structure is used in the ovpn kernel module
to wrap and carry around a standard kernel socket.
ovpn takes ownership of passed sockets and therefore an ovpn
specific objects is attached to them for status tracking
purposes.
Initially only UDP support is introduced. TCP will come in a later
patch.
Cc: willemdebruijn.kernel@gmail.com
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/Makefile | 2 +
drivers/net/ovpn/main.c | 2 +-
drivers/net/ovpn/peer.c | 28 +++++--
drivers/net/ovpn/peer.h | 6 +-
drivers/net/ovpn/socket.c | 208 ++++++++++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/socket.h | 38 +++++++++
drivers/net/ovpn/udp.c | 75 +++++++++++++++++
drivers/net/ovpn/udp.h | 19 +++++
include/uapi/linux/udp.h | 1 +
9 files changed, 372 insertions(+), 7 deletions(-)
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
index 618328ae338861b9764b42485df71ebd0fc1fe90..164f2058ea8e6dc5b9287afb59758a268b2f8b56 100644
--- a/drivers/net/ovpn/Makefile
+++ b/drivers/net/ovpn/Makefile
@@ -13,3 +13,5 @@ ovpn-y += io.o
ovpn-y += netlink.o
ovpn-y += netlink-gen.o
ovpn-y += peer.o
+ovpn-y += socket.o
+ovpn-y += udp.o
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index 3c72b80095a0ed8f2f2064fdfa556f750f1c7061..e58739d82da54001a346c38e5c5a882589eb3801 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -185,7 +185,7 @@ static int ovpn_netdev_notifier_call(struct notifier_block *nb,
ovpn->registered = false;
if (ovpn->mode == OVPN_MODE_P2P)
- ovpn_peer_release_p2p(ovpn,
+ ovpn_peer_release_p2p(ovpn, NULL,
OVPN_DEL_PEER_REASON_TEARDOWN);
break;
case NETDEV_POST_INIT:
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 338069c99248f42b0c4aeb44b2b9d3a35f8bebeb..0bb6c15171848acbc055829a3d2aefd26c5b810a 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -16,17 +16,20 @@
#include "main.h"
#include "netlink.h"
#include "peer.h"
+#include "socket.h"
static void unlock_ovpn(struct ovpn_priv *ovpn,
- struct llist_head *release_list)
+ struct llist_head *release_list)
__releases(&ovpn->lock)
{
struct ovpn_peer *peer;
spin_unlock_bh(&ovpn->lock);
- llist_for_each_entry(peer, release_list->first, release_entry)
+ llist_for_each_entry(peer, release_list->first, release_entry) {
+ ovpn_socket_release(peer);
ovpn_peer_put(peer);
+ }
}
/**
@@ -394,18 +397,33 @@ int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason)
/**
* ovpn_peer_release_p2p - release peer upon P2P device teardown
* @ovpn: the instance being torn down
+ * @sk: if not NULL, release peer only if it's using this specific socket
* @reason: the reason for releasing the peer
*/
-void ovpn_peer_release_p2p(struct ovpn_priv *ovpn,
+void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, struct sock *sk,
enum ovpn_del_peer_reason reason)
{
+ struct ovpn_socket *ovpn_sock;
LLIST_HEAD(release_list);
struct ovpn_peer *peer;
spin_lock_bh(&ovpn->lock);
peer = rcu_dereference_protected(ovpn->peer,
lockdep_is_held(&ovpn->lock));
- if (peer)
- ovpn_peer_remove(peer, reason, &release_list);
+ if (!peer) {
+ spin_unlock_bh(&ovpn->lock);
+ return;
+ }
+
+ if (sk) {
+ ovpn_sock = rcu_access_pointer(peer->sock);
+ if (!ovpn_sock || ovpn_sock->sock->sk != sk) {
+ spin_unlock_bh(&ovpn->lock);
+ ovpn_peer_put(peer);
+ return;
+ }
+ }
+
+ ovpn_peer_remove(peer, reason, &release_list);
unlock_ovpn(ovpn, &release_list);
}
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index fd2e7625990a73f61bf5bb4c051929828d9996bd..29c9065cedccb156ec6ca6d9b692372e8fc89a2d 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -12,6 +12,8 @@
#include <net/dst_cache.h>
+#include "socket.h"
+
/**
* struct ovpn_peer - the main remote peer object
* @ovpn: main openvpn instance this peer belongs to
@@ -20,6 +22,7 @@
* @vpn_addrs: IP addresses assigned over the tunnel
* @vpn_addrs.ipv4: IPv4 assigned to peer on the tunnel
* @vpn_addrs.ipv6: IPv6 assigned to peer on the tunnel
+ * @sock: the socket being used to talk to this peer
* @dst_cache: cache for dst_entry used to send to peer
* @bind: remote peer binding
* @delete_reason: why peer was deleted (i.e. timeout, transport error, ..)
@@ -36,6 +39,7 @@ struct ovpn_peer {
struct in_addr ipv4;
struct in6_addr ipv6;
} vpn_addrs;
+ struct ovpn_socket __rcu *sock;
struct dst_cache dst_cache;
struct ovpn_bind __rcu *bind;
enum ovpn_del_peer_reason delete_reason;
@@ -70,7 +74,7 @@ static inline void ovpn_peer_put(struct ovpn_peer *peer)
struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id);
int ovpn_peer_add(struct ovpn_priv *ovpn, struct ovpn_peer *peer);
int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason);
-void ovpn_peer_release_p2p(struct ovpn_priv *ovpn,
+void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, struct sock *sk,
enum ovpn_del_peer_reason reason);
struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_priv *ovpn,
diff --git a/drivers/net/ovpn/socket.c b/drivers/net/ovpn/socket.c
new file mode 100644
index 0000000000000000000000000000000000000000..0a1ba3f75aa7438502dec4c86dcef8637d5ebffa
--- /dev/null
+++ b/drivers/net/ovpn/socket.c
@@ -0,0 +1,208 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/udp.h>
+
+#include "ovpnpriv.h"
+#include "main.h"
+#include "io.h"
+#include "peer.h"
+#include "socket.h"
+#include "udp.h"
+
+static void ovpn_socket_release_kref(struct kref *kref)
+{
+ struct ovpn_socket *sock = container_of(kref, struct ovpn_socket,
+ refcount);
+
+ if (sock->sock->sk->sk_protocol == IPPROTO_UDP)
+ ovpn_udp_socket_detach(sock);
+
+ kfree_rcu(sock, rcu);
+}
+
+/**
+ * ovpn_socket_put - decrease reference counter
+ * @peer: peer whose socket reference counter should be decreased
+ * @sock: the RCU protected peer socket
+ *
+ * This function is only used internally. Users willing to release
+ * references to the ovpn_socket should use ovpn_socket_release()
+ */
+static void ovpn_socket_put(struct ovpn_peer *peer, struct ovpn_socket *sock)
+{
+ kref_put(&sock->refcount, ovpn_socket_release_kref);
+}
+
+/**
+ * ovpn_socket_release - release resources owned by socket user
+ * @peer: peer whose socket should be released
+ *
+ * This function should be invoked when the user is shutting
+ * down and wants to drop its link to the socket.
+ *
+ * In case of UDP, the detach routine will drop a reference to the
+ * ovpn netdev, pointed by the ovpn_socket.
+ *
+ * In case of TCP, releasing the socket will cause dropping
+ * the refcounter for the peer it is linked to, thus allowing the peer
+ * disappear as well.
+ *
+ * This function is expected to be invoked exactly once per peer
+ *
+ * NOTE: this function may sleep
+ */
+void ovpn_socket_release(struct ovpn_peer *peer)
+{
+ struct ovpn_socket *sock;
+
+ might_sleep();
+
+ /* release may be invoked after socket was detached */
+ rcu_read_lock();
+ sock = rcu_dereference_protected(peer->sock, true);
+ if (!sock) {
+ rcu_read_unlock();
+ return;
+ }
+ rcu_assign_pointer(peer->sock, NULL);
+ rcu_read_unlock();
+
+ /* sanity check: we should not end up here if the socket
+ * was already closed
+ */
+ if (!sock->sock->sk) {
+ DEBUG_NET_WARN_ON_ONCE(1);
+ return;
+ }
+
+ /* Drop the reference while holding the sock lock to avoid
+ * concurrent ovpn_socket_new call to mess up with a partially
+ * detached socket.
+ *
+ * Holding the lock ensures that a socket with refcnt 0 is fully
+ * detached before it can be picked by a concurrent reader.
+ */
+ lock_sock(sock->sock->sk);
+ ovpn_socket_put(peer, sock);
+ release_sock(sock->sock->sk);
+
+ /* align all readers with sk_user_data being NULL */
+ synchronize_rcu();
+}
+
+static bool ovpn_socket_hold(struct ovpn_socket *sock)
+{
+ return kref_get_unless_zero(&sock->refcount);
+}
+
+static int ovpn_socket_attach(struct ovpn_socket *sock, struct ovpn_peer *peer)
+{
+ if (sock->sock->sk->sk_protocol == IPPROTO_UDP)
+ return ovpn_udp_socket_attach(sock, peer->ovpn);
+
+ return -EOPNOTSUPP;
+}
+
+/**
+ * ovpn_socket_new - create a new socket and initialize it
+ * @sock: the kernel socket to embed
+ * @peer: the peer reachable via this socket
+ *
+ * Return: an openvpn socket on success or a negative error code otherwise
+ */
+struct ovpn_socket *ovpn_socket_new(struct socket *sock, struct ovpn_peer *peer)
+{
+ struct ovpn_socket *ovpn_sock;
+ int ret;
+
+ lock_sock(sock->sk);
+
+ /* a TCP socket can only be owned by a single peer, therefore there
+ * can't be any other user
+ */
+ if (sock->sk->sk_protocol == IPPROTO_TCP && sock->sk->sk_user_data) {
+ ovpn_sock = ERR_PTR(-EBUSY);
+ goto sock_release;
+ }
+
+ /* a UDP socket can be shared across multiple peers, but we must make
+ * sure it is not owned by something else
+ */
+ if (sock->sk->sk_protocol == IPPROTO_UDP) {
+ u8 type = READ_ONCE(udp_sk(sock->sk)->encap_type);
+
+ /* socket owned by other encapsulation module */
+ if (type && type != UDP_ENCAP_OVPNINUDP) {
+ ovpn_sock = ERR_PTR(-EBUSY);
+ goto sock_release;
+ }
+
+ rcu_read_lock();
+ ovpn_sock = rcu_dereference_sk_user_data(sock->sk);
+ if (ovpn_sock) {
+ /* socket owned by another ovpn instance, we can't use it */
+ if (ovpn_sock->ovpn != peer->ovpn) {
+ ovpn_sock = ERR_PTR(-EBUSY);
+ rcu_read_unlock();
+ goto sock_release;
+ }
+
+ /* this socket is already owned by this instance,
+ * therefore we can increase the refcounter and
+ * use it as expected
+ */
+ if (WARN_ON(!ovpn_socket_hold(ovpn_sock))) {
+ /* this should never happen because setting
+ * the refcnt to 0 and detaching the socket
+ * is expected to be atomic
+ */
+ ovpn_sock = ERR_PTR(-EAGAIN);
+ rcu_read_unlock();
+ goto sock_release;
+ }
+
+ /* caller is expected to increase the sock
+ * refcounter before passing it to this
+ * function. For this reason we drop it if
+ * not needed, like when this socket is already
+ * owned.
+ */
+ rcu_read_unlock();
+ goto sock_release;
+ }
+ rcu_read_unlock();
+ }
+
+ /* socket is not owned: attach to this ovpn instance */
+
+ ovpn_sock = kzalloc(sizeof(*ovpn_sock), GFP_KERNEL);
+ if (!ovpn_sock) {
+ ovpn_sock = ERR_PTR(-ENOMEM);
+ goto sock_release;
+ }
+
+ ovpn_sock->ovpn = peer->ovpn;
+ ovpn_sock->sock = sock;
+ kref_init(&ovpn_sock->refcount);
+
+ ret = ovpn_socket_attach(ovpn_sock, peer);
+ if (ret < 0) {
+ kfree(ovpn_sock);
+ ovpn_sock = ERR_PTR(ret);
+ goto sock_release;
+ }
+
+ rcu_assign_sk_user_data(sock->sk, ovpn_sock);
+sock_release:
+ release_sock(sock->sk);
+ return ovpn_sock;
+}
diff --git a/drivers/net/ovpn/socket.h b/drivers/net/ovpn/socket.h
new file mode 100644
index 0000000000000000000000000000000000000000..ade8c94619d7b2f905b5284373dc73f590188399
--- /dev/null
+++ b/drivers/net/ovpn/socket.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_SOCK_H_
+#define _NET_OVPN_SOCK_H_
+
+#include <linux/net.h>
+#include <linux/kref.h>
+#include <net/sock.h>
+
+struct ovpn_priv;
+struct ovpn_peer;
+
+/**
+ * struct ovpn_socket - a kernel socket referenced in the ovpn code
+ * @ovpn: ovpn instance owning this socket (UDP only)
+ * @sock: the low level sock object
+ * @refcount: amount of contexts currently referencing this object
+ * @rcu: member used to schedule RCU destructor callback
+ */
+struct ovpn_socket {
+ struct ovpn_priv *ovpn;
+ struct socket *sock;
+ struct kref refcount;
+ struct rcu_head rcu;
+};
+
+struct ovpn_socket *ovpn_socket_new(struct socket *sock,
+ struct ovpn_peer *peer);
+void ovpn_socket_release(struct ovpn_peer *peer);
+
+#endif /* _NET_OVPN_SOCK_H_ */
diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c
new file mode 100644
index 0000000000000000000000000000000000000000..91970e66a4340370a96c1fc42321f94574302143
--- /dev/null
+++ b/drivers/net/ovpn/udp.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2025 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/netdevice.h>
+#include <linux/socket.h>
+#include <linux/udp.h>
+#include <net/udp.h>
+
+#include "ovpnpriv.h"
+#include "main.h"
+#include "socket.h"
+#include "udp.h"
+
+/**
+ * ovpn_udp_socket_attach - set udp-tunnel CBs on socket and link it to ovpn
+ * @ovpn_sock: socket to configure
+ * @ovpn: the openvp instance to link
+ *
+ * After invoking this function, the sock will be controlled by ovpn so that
+ * any incoming packet may be processed by ovpn first.
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+int ovpn_udp_socket_attach(struct ovpn_socket *ovpn_sock,
+ struct ovpn_priv *ovpn)
+{
+ struct socket *sock = ovpn_sock->sock;
+ struct ovpn_socket *old_data;
+ int ret = 0;
+
+ /* make sure no pre-existing encapsulation handler exists */
+ rcu_read_lock();
+ old_data = rcu_dereference_sk_user_data(sock->sk);
+ if (!old_data) {
+ /* socket is currently unused - we can take it */
+ rcu_read_unlock();
+ return 0;
+ }
+
+ /* socket is in use. We need to understand if it's owned by this ovpn
+ * instance or by something else.
+ * In the former case, we can increase the refcounter and happily
+ * use it, because the same UDP socket is expected to be shared among
+ * different peers.
+ *
+ * Unlikely TCP, a single UDP socket can be used to talk to many remote
+ * hosts and therefore openvpn instantiates one only for all its peers
+ */
+ if ((READ_ONCE(udp_sk(sock->sk)->encap_type) == UDP_ENCAP_OVPNINUDP) &&
+ old_data->ovpn == ovpn) {
+ netdev_dbg(ovpn->dev,
+ "provided socket already owned by this interface\n");
+ ret = -EALREADY;
+ } else {
+ netdev_dbg(ovpn->dev,
+ "provided socket already taken by other user\n");
+ ret = -EBUSY;
+ }
+ rcu_read_unlock();
+
+ return ret;
+}
+
+/**
+ * ovpn_udp_socket_detach - clean udp-tunnel status for this socket
+ * @ovpn_sock: the socket to clean
+ */
+void ovpn_udp_socket_detach(struct ovpn_socket *ovpn_sock)
+{
+}
diff --git a/drivers/net/ovpn/udp.h b/drivers/net/ovpn/udp.h
new file mode 100644
index 0000000000000000000000000000000000000000..1c8fb6fe402dc1cfdc10fddc9cf5b74d7d6887ce
--- /dev/null
+++ b/drivers/net/ovpn/udp.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2025 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_UDP_H_
+#define _NET_OVPN_UDP_H_
+
+struct ovpn_priv;
+struct socket;
+
+int ovpn_udp_socket_attach(struct ovpn_socket *ovpn_sock,
+ struct ovpn_priv *ovpn);
+void ovpn_udp_socket_detach(struct ovpn_socket *ovpn_sock);
+
+#endif /* _NET_OVPN_UDP_H_ */
diff --git a/include/uapi/linux/udp.h b/include/uapi/linux/udp.h
index d85d671deed3c78f6969189281b9083dcac000c6..edca3e430305a6bffc34e617421f1f3071582e69 100644
--- a/include/uapi/linux/udp.h
+++ b/include/uapi/linux/udp.h
@@ -43,5 +43,6 @@ struct udphdr {
#define UDP_ENCAP_GTP1U 5 /* 3GPP TS 29.060 */
#define UDP_ENCAP_RXRPC 6
#define TCP_ENCAP_ESPINTCP 7 /* Yikes, this is really xfrm encap types. */
+#define UDP_ENCAP_OVPNINUDP 8 /* OpenVPN traffic */
#endif /* _UAPI_LINUX_UDP_H */
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 07/24] ovpn: implement basic TX path (UDP)
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (5 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 06/24] ovpn: introduce the ovpn_socket object Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 08/24] ovpn: implement basic RX " Antonio Quartulli
` (16 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
Packets sent over the ovpn interface are processed and transmitted to the
connected peer, if any.
Implementation is UDP only. TCP will be added by a later patch.
Note: no crypto/encapsulation exists yet. Packets are just captured and
sent.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/Kconfig | 1 +
drivers/net/ovpn/io.c | 137 ++++++++++++++++++++++++++-
drivers/net/ovpn/peer.c | 32 +++++++
drivers/net/ovpn/peer.h | 2 +
drivers/net/ovpn/skb.h | 55 +++++++++++
drivers/net/ovpn/socket.c | 3 +-
drivers/net/ovpn/udp.c | 236 +++++++++++++++++++++++++++++++++++++++++++++-
drivers/net/ovpn/udp.h | 6 ++
8 files changed, 468 insertions(+), 4 deletions(-)
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index dfd1ad96230317c4118b63c9c98d0a631f6cbb21..b18ff941944e2e92aa769d1ebbc3d1782611fc06 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -120,6 +120,7 @@ config OVPN
depends on NET && INET
depends on IPV6 || !IPV6
select DST_CACHE
+ select NET_UDP_TUNNEL
help
This module enhances the performance of the OpenVPN userspace software
by offloading the data channel processing to kernelspace.
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index 4b71c38165d7adbb1a2d1a64d27a13b7f76cfbfe..94b466bf2ef70d60d3e60d9820b64877c44f2e51 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -9,14 +9,149 @@
#include <linux/netdevice.h>
#include <linux/skbuff.h>
+#include <net/gso.h>
#include "io.h"
+#include "ovpnpriv.h"
+#include "peer.h"
+#include "udp.h"
+#include "skb.h"
+#include "socket.h"
+
+static void ovpn_encrypt_post(struct sk_buff *skb, int ret)
+{
+ struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;
+ struct ovpn_socket *sock;
+
+ if (unlikely(ret < 0))
+ goto err;
+
+ skb_mark_not_on_list(skb);
+
+ rcu_read_lock();
+ sock = rcu_dereference(peer->sock);
+ if (unlikely(!sock))
+ goto err_unlock;
+
+ switch (sock->sock->sk->sk_protocol) {
+ case IPPROTO_UDP:
+ ovpn_udp_send_skb(peer, sock->sock, skb);
+ break;
+ default:
+ /* no transport configured yet */
+ goto err_unlock;
+ }
+ /* skb passed down the stack - don't free it */
+ skb = NULL;
+err_unlock:
+ rcu_read_unlock();
+err:
+ if (unlikely(skb))
+ dev_core_stats_tx_dropped_inc(peer->ovpn->dev);
+ ovpn_peer_put(peer);
+ kfree_skb(skb);
+}
+
+static bool ovpn_encrypt_one(struct ovpn_peer *peer, struct sk_buff *skb)
+{
+ ovpn_skb_cb(skb)->peer = peer;
+
+ /* take a reference to the peer because the crypto code may run async.
+ * ovpn_encrypt_post() will release it upon completion
+ */
+ if (unlikely(!ovpn_peer_hold(peer))) {
+ DEBUG_NET_WARN_ON_ONCE(1);
+ return false;
+ }
+
+ ovpn_encrypt_post(skb, 0);
+ return true;
+}
+
+/* send skb to connected peer, if any */
+static void ovpn_send(struct ovpn_priv *ovpn, struct sk_buff *skb,
+ struct ovpn_peer *peer)
+{
+ struct sk_buff *curr, *next;
+
+ /* this might be a GSO-segmented skb list: process each skb
+ * independently
+ */
+ skb_list_walk_safe(skb, curr, next) {
+ if (unlikely(!ovpn_encrypt_one(peer, curr))) {
+ dev_core_stats_tx_dropped_inc(ovpn->dev);
+ kfree_skb(curr);
+ }
+ }
+
+ ovpn_peer_put(peer);
+}
/* Send user data to the network
*/
netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev)
{
+ struct ovpn_priv *ovpn = netdev_priv(dev);
+ struct sk_buff *segments, *curr, *next;
+ struct sk_buff_head skb_list;
+ struct ovpn_peer *peer;
+ __be16 proto;
+ int ret;
+
+ /* reset netfilter state */
+ nf_reset_ct(skb);
+
+ /* verify IP header size in network packet */
+ proto = ovpn_ip_check_protocol(skb);
+ if (unlikely(!proto || skb->protocol != proto))
+ goto drop;
+
+ if (skb_is_gso(skb)) {
+ segments = skb_gso_segment(skb, 0);
+ if (IS_ERR(segments)) {
+ ret = PTR_ERR(segments);
+ net_err_ratelimited("%s: cannot segment payload packet: %d\n",
+ netdev_name(dev), ret);
+ goto drop;
+ }
+
+ consume_skb(skb);
+ skb = segments;
+ }
+
+ /* from this moment on, "skb" might be a list */
+
+ __skb_queue_head_init(&skb_list);
+ skb_list_walk_safe(skb, curr, next) {
+ skb_mark_not_on_list(curr);
+
+ curr = skb_share_check(curr, GFP_ATOMIC);
+ if (unlikely(!curr)) {
+ net_err_ratelimited("%s: skb_share_check failed for payload packet\n",
+ netdev_name(dev));
+ dev_core_stats_tx_dropped_inc(ovpn->dev);
+ continue;
+ }
+
+ __skb_queue_tail(&skb_list, curr);
+ }
+ skb_list.prev->next = NULL;
+
+ /* retrieve peer serving the destination IP of this packet */
+ peer = ovpn_peer_get_by_dst(ovpn, skb);
+ if (unlikely(!peer)) {
+ net_dbg_ratelimited("%s: no peer to send data to\n",
+ netdev_name(ovpn->dev));
+ goto drop;
+ }
+
+ ovpn_send(ovpn, skb_list.next, peer);
+
+ return NETDEV_TX_OK;
+
+drop:
+ dev_core_stats_tx_dropped_inc(ovpn->dev);
skb_tx_error(skb);
- kfree_skb(skb);
+ kfree_skb_list(skb);
return NET_XMIT_DROP;
}
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 0bb6c15171848acbc055829a3d2aefd26c5b810a..10eabd62ae7237162a36a333b41c748901a7d888 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -294,6 +294,38 @@ static void ovpn_peer_remove(struct ovpn_peer *peer,
llist_add(&peer->release_entry, release_list);
}
+/**
+ * ovpn_peer_get_by_dst - Lookup peer to send skb to
+ * @ovpn: the private data representing the current VPN session
+ * @skb: the skb to extract the destination address from
+ *
+ * This function takes a tunnel packet and looks up the peer to send it to
+ * after encapsulation. The skb is expected to be the in-tunnel packet, without
+ * any OpenVPN related header.
+ *
+ * Assume that the IP header is accessible in the skb data.
+ *
+ * Return: the peer if found or NULL otherwise.
+ */
+struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_priv *ovpn,
+ struct sk_buff *skb)
+{
+ struct ovpn_peer *peer = NULL;
+
+ /* in P2P mode, no matter the destination, packets are always sent to
+ * the single peer listening on the other side
+ */
+ if (ovpn->mode == OVPN_MODE_P2P) {
+ rcu_read_lock();
+ peer = rcu_dereference(ovpn->peer);
+ if (unlikely(peer && !ovpn_peer_hold(peer)))
+ peer = NULL;
+ rcu_read_unlock();
+ }
+
+ return peer;
+}
+
/**
* ovpn_peer_add_p2p - add peer to related tables in a P2P instance
* @ovpn: the instance to add the peer to
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index 29c9065cedccb156ec6ca6d9b692372e8fc89a2d..fef04311c1593db4ccfa3c417487b3d4faaae9d7 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -80,5 +80,7 @@ void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, struct sock *sk,
struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_priv *ovpn,
struct sk_buff *skb);
struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_priv *ovpn, u32 peer_id);
+struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_priv *ovpn,
+ struct sk_buff *skb);
#endif /* _NET_OVPN_OVPNPEER_H_ */
diff --git a/drivers/net/ovpn/skb.h b/drivers/net/ovpn/skb.h
new file mode 100644
index 0000000000000000000000000000000000000000..9db7a9adebdb4cc493f162f89fb2e9c6301fa213
--- /dev/null
+++ b/drivers/net/ovpn/skb.h
@@ -0,0 +1,55 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ * James Yonan <james@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_SKB_H_
+#define _NET_OVPN_SKB_H_
+
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/skbuff.h>
+#include <linux/socket.h>
+#include <linux/types.h>
+
+struct ovpn_cb {
+ struct ovpn_peer *peer;
+};
+
+static inline struct ovpn_cb *ovpn_skb_cb(struct sk_buff *skb)
+{
+ BUILD_BUG_ON(sizeof(struct ovpn_cb) > sizeof(skb->cb));
+ return (struct ovpn_cb *)skb->cb;
+}
+
+/* Return IP protocol version from skb header.
+ * Return 0 if protocol is not IPv4/IPv6 or cannot be read.
+ */
+static inline __be16 ovpn_ip_check_protocol(struct sk_buff *skb)
+{
+ __be16 proto = 0;
+
+ /* skb could be non-linear,
+ * make sure IP header is in non-fragmented part
+ */
+ if (!pskb_network_may_pull(skb, sizeof(struct iphdr)))
+ return 0;
+
+ if (ip_hdr(skb)->version == 4) {
+ proto = htons(ETH_P_IP);
+ } else if (ip_hdr(skb)->version == 6) {
+ if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr)))
+ return 0;
+ proto = htons(ETH_P_IPV6);
+ }
+
+ return proto;
+}
+
+#endif /* _NET_OVPN_SKB_H_ */
diff --git a/drivers/net/ovpn/socket.c b/drivers/net/ovpn/socket.c
index 0a1ba3f75aa7438502dec4c86dcef8637d5ebffa..a4a8686f2e2995dca163d5b96c6c897b86434967 100644
--- a/drivers/net/ovpn/socket.c
+++ b/drivers/net/ovpn/socket.c
@@ -190,9 +190,8 @@ struct ovpn_socket *ovpn_socket_new(struct socket *sock, struct ovpn_peer *peer)
goto sock_release;
}
- ovpn_sock->ovpn = peer->ovpn;
- ovpn_sock->sock = sock;
kref_init(&ovpn_sock->refcount);
+ ovpn_sock->sock = sock;
ret = ovpn_socket_attach(ovpn_sock, peer);
if (ret < 0) {
diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c
index 91970e66a4340370a96c1fc42321f94574302143..ae76ae6d372f565715a39ee24e3fba14f1c1370e 100644
--- a/drivers/net/ovpn/udp.c
+++ b/drivers/net/ovpn/udp.c
@@ -7,15 +7,249 @@
*/
#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
+#include <linux/skbuff.h>
#include <linux/socket.h>
#include <linux/udp.h>
+#include <net/addrconf.h>
+#include <net/dst_cache.h>
+#include <net/route.h>
+#include <net/ipv6_stubs.h>
#include <net/udp.h>
+#include <net/udp_tunnel.h>
#include "ovpnpriv.h"
#include "main.h"
+#include "bind.h"
+#include "io.h"
+#include "peer.h"
#include "socket.h"
#include "udp.h"
+/**
+ * ovpn_udp4_output - send IPv4 packet over udp socket
+ * @peer: the destination peer
+ * @bind: the binding related to the destination peer
+ * @cache: dst cache
+ * @sk: the socket to send the packet over
+ * @skb: the packet to send
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+static int ovpn_udp4_output(struct ovpn_peer *peer, struct ovpn_bind *bind,
+ struct dst_cache *cache, struct sock *sk,
+ struct sk_buff *skb)
+{
+ struct rtable *rt;
+ struct flowi4 fl = {
+ .saddr = bind->local.ipv4.s_addr,
+ .daddr = bind->remote.in4.sin_addr.s_addr,
+ .fl4_sport = inet_sk(sk)->inet_sport,
+ .fl4_dport = bind->remote.in4.sin_port,
+ .flowi4_proto = sk->sk_protocol,
+ .flowi4_mark = sk->sk_mark,
+ };
+ int ret;
+
+ local_bh_disable();
+ rt = dst_cache_get_ip4(cache, &fl.saddr);
+ if (rt)
+ goto transmit;
+
+ if (unlikely(!inet_confirm_addr(sock_net(sk), NULL, 0, fl.saddr,
+ RT_SCOPE_HOST))) {
+ /* we may end up here when the cached address is not usable
+ * anymore. In this case we reset address/cache and perform a
+ * new look up
+ */
+ fl.saddr = 0;
+ spin_lock_bh(&peer->lock);
+ bind->local.ipv4.s_addr = 0;
+ spin_unlock_bh(&peer->lock);
+ dst_cache_reset(cache);
+ }
+
+ rt = ip_route_output_flow(sock_net(sk), &fl, sk);
+ if (IS_ERR(rt) && PTR_ERR(rt) == -EINVAL) {
+ fl.saddr = 0;
+ spin_lock_bh(&peer->lock);
+ bind->local.ipv4.s_addr = 0;
+ spin_unlock_bh(&peer->lock);
+ dst_cache_reset(cache);
+
+ rt = ip_route_output_flow(sock_net(sk), &fl, sk);
+ }
+
+ if (IS_ERR(rt)) {
+ ret = PTR_ERR(rt);
+ net_dbg_ratelimited("%s: no route to host %pISpc: %d\n",
+ netdev_name(peer->ovpn->dev),
+ &bind->remote.in4,
+ ret);
+ goto err;
+ }
+ dst_cache_set_ip4(cache, &rt->dst, fl.saddr);
+
+transmit:
+ udp_tunnel_xmit_skb(rt, sk, skb, fl.saddr, fl.daddr, 0,
+ ip4_dst_hoplimit(&rt->dst), 0, fl.fl4_sport,
+ fl.fl4_dport, false, sk->sk_no_check_tx);
+ ret = 0;
+err:
+ local_bh_enable();
+ return ret;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+/**
+ * ovpn_udp6_output - send IPv6 packet over udp socket
+ * @peer: the destination peer
+ * @bind: the binding related to the destination peer
+ * @cache: dst cache
+ * @sk: the socket to send the packet over
+ * @skb: the packet to send
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+static int ovpn_udp6_output(struct ovpn_peer *peer, struct ovpn_bind *bind,
+ struct dst_cache *cache, struct sock *sk,
+ struct sk_buff *skb)
+{
+ struct dst_entry *dst;
+ int ret;
+
+ struct flowi6 fl = {
+ .saddr = bind->local.ipv6,
+ .daddr = bind->remote.in6.sin6_addr,
+ .fl6_sport = inet_sk(sk)->inet_sport,
+ .fl6_dport = bind->remote.in6.sin6_port,
+ .flowi6_proto = sk->sk_protocol,
+ .flowi6_mark = sk->sk_mark,
+ .flowi6_oif = bind->remote.in6.sin6_scope_id,
+ };
+
+ local_bh_disable();
+ dst = dst_cache_get_ip6(cache, &fl.saddr);
+ if (dst)
+ goto transmit;
+
+ if (unlikely(!ipv6_chk_addr(sock_net(sk), &fl.saddr, NULL, 0))) {
+ /* we may end up here when the cached address is not usable
+ * anymore. In this case we reset address/cache and perform a
+ * new look up
+ */
+ fl.saddr = in6addr_any;
+ spin_lock_bh(&peer->lock);
+ bind->local.ipv6 = in6addr_any;
+ spin_unlock_bh(&peer->lock);
+ dst_cache_reset(cache);
+ }
+
+ dst = ipv6_stub->ipv6_dst_lookup_flow(sock_net(sk), sk, &fl, NULL);
+ if (IS_ERR(dst)) {
+ ret = PTR_ERR(dst);
+ net_dbg_ratelimited("%s: no route to host %pISpc: %d\n",
+ netdev_name(peer->ovpn->dev),
+ &bind->remote.in6, ret);
+ goto err;
+ }
+ dst_cache_set_ip6(cache, dst, &fl.saddr);
+
+transmit:
+ udp_tunnel6_xmit_skb(dst, sk, skb, skb->dev, &fl.saddr, &fl.daddr, 0,
+ ip6_dst_hoplimit(dst), 0, fl.fl6_sport,
+ fl.fl6_dport, udp_get_no_check6_tx(sk));
+ ret = 0;
+err:
+ local_bh_enable();
+ return ret;
+}
+#endif
+
+/**
+ * ovpn_udp_output - transmit skb using udp-tunnel
+ * @peer: the destination peer
+ * @cache: dst cache
+ * @sk: the socket to send the packet over
+ * @skb: the packet to send
+ *
+ * rcu_read_lock should be held on entry.
+ * On return, the skb is consumed.
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+static int ovpn_udp_output(struct ovpn_peer *peer, struct dst_cache *cache,
+ struct sock *sk, struct sk_buff *skb)
+{
+ struct ovpn_bind *bind;
+ int ret;
+
+ /* set sk to null if skb is already orphaned */
+ if (!skb->destructor)
+ skb->sk = NULL;
+
+ /* always permit openvpn-created packets to be (outside) fragmented */
+ skb->ignore_df = 1;
+
+ rcu_read_lock();
+ bind = rcu_dereference(peer->bind);
+ if (unlikely(!bind)) {
+ net_warn_ratelimited("%s: no bind for remote peer %u\n",
+ netdev_name(peer->ovpn->dev), peer->id);
+ ret = -ENODEV;
+ goto out;
+ }
+
+ switch (bind->remote.in4.sin_family) {
+ case AF_INET:
+ ret = ovpn_udp4_output(peer, bind, cache, sk, skb);
+ break;
+#if IS_ENABLED(CONFIG_IPV6)
+ case AF_INET6:
+ ret = ovpn_udp6_output(peer, bind, cache, sk, skb);
+ break;
+#endif
+ default:
+ ret = -EAFNOSUPPORT;
+ break;
+ }
+
+out:
+ rcu_read_unlock();
+ return ret;
+}
+
+/**
+ * ovpn_udp_send_skb - prepare skb and send it over via UDP
+ * @peer: the destination peer
+ * @sock: the RCU protected peer socket
+ * @skb: the packet to send
+ */
+void ovpn_udp_send_skb(struct ovpn_peer *peer, struct socket *sock,
+ struct sk_buff *skb)
+{
+ int ret = -1;
+
+ skb->dev = peer->ovpn->dev;
+ /* no checksum performed at this layer */
+ skb->ip_summed = CHECKSUM_NONE;
+
+ /* get socket info */
+ if (unlikely(!sock)) {
+ net_warn_ratelimited("%s: no sock for remote peer %u\n",
+ netdev_name(peer->ovpn->dev), peer->id);
+ goto out;
+ }
+
+ /* crypto layer -> transport (UDP) */
+ ret = ovpn_udp_output(peer, &peer->dst_cache, sock->sk, skb);
+out:
+ if (unlikely(ret < 0)) {
+ kfree_skb(skb);
+ return;
+ }
+}
+
/**
* ovpn_udp_socket_attach - set udp-tunnel CBs on socket and link it to ovpn
* @ovpn_sock: socket to configure
@@ -31,7 +265,7 @@ int ovpn_udp_socket_attach(struct ovpn_socket *ovpn_sock,
{
struct socket *sock = ovpn_sock->sock;
struct ovpn_socket *old_data;
- int ret = 0;
+ int ret;
/* make sure no pre-existing encapsulation handler exists */
rcu_read_lock();
diff --git a/drivers/net/ovpn/udp.h b/drivers/net/ovpn/udp.h
index 1c8fb6fe402dc1cfdc10fddc9cf5b74d7d6887ce..9994eb6e04283247d8ffc729966345810f84b22b 100644
--- a/drivers/net/ovpn/udp.h
+++ b/drivers/net/ovpn/udp.h
@@ -9,6 +9,9 @@
#ifndef _NET_OVPN_UDP_H_
#define _NET_OVPN_UDP_H_
+#include <net/sock.h>
+
+struct ovpn_peer;
struct ovpn_priv;
struct socket;
@@ -16,4 +19,7 @@ int ovpn_udp_socket_attach(struct ovpn_socket *ovpn_sock,
struct ovpn_priv *ovpn);
void ovpn_udp_socket_detach(struct ovpn_socket *ovpn_sock);
+void ovpn_udp_send_skb(struct ovpn_peer *peer, struct socket *sock,
+ struct sk_buff *skb);
+
#endif /* _NET_OVPN_UDP_H_ */
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 08/24] ovpn: implement basic RX path (UDP)
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (6 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 07/24] ovpn: implement basic TX path (UDP) Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 09/24] ovpn: implement packet processing Antonio Quartulli
` (15 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
Packets received over the socket are forwarded to the user device.
Implementation is UDP only. TCP will be added by a later patch.
Note: no decryption/decapsulation exists yet, packets are forwarded as
they arrive without much processing.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/io.c | 64 ++++++++++++++++++++-
drivers/net/ovpn/io.h | 2 +
drivers/net/ovpn/main.c | 14 ++++-
drivers/net/ovpn/ovpnpriv.h | 3 +
drivers/net/ovpn/proto.h | 50 +++++++++++++++-
drivers/net/ovpn/socket.c | 13 ++++-
drivers/net/ovpn/socket.h | 9 ++-
drivers/net/ovpn/udp.c | 135 ++++++++++++++++++++++++++++++++++++++++++++
net/ipv6/udp.c | 1 +
9 files changed, 286 insertions(+), 5 deletions(-)
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index 94b466bf2ef70d60d3e60d9820b64877c44f2e51..46ad27e8eb8425f810c7d2b6c63984ea008d90fa 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -9,15 +9,77 @@
#include <linux/netdevice.h>
#include <linux/skbuff.h>
+#include <net/gro_cells.h>
#include <net/gso.h>
-#include "io.h"
#include "ovpnpriv.h"
#include "peer.h"
+#include "io.h"
+#include "netlink.h"
+#include "proto.h"
#include "udp.h"
#include "skb.h"
#include "socket.h"
+/* Called after decrypt to write the IP packet to the device.
+ * This method is expected to manage/free the skb.
+ */
+static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb)
+{
+ unsigned int pkt_len;
+ int ret;
+
+ /* we can't guarantee the packet wasn't corrupted before entering the
+ * VPN, therefore we give other layers a chance to check that
+ */
+ skb->ip_summed = CHECKSUM_NONE;
+
+ /* skb hash for transport packet no longer valid after decapsulation */
+ skb_clear_hash(skb);
+
+ /* post-decrypt scrub -- prepare to inject encapsulated packet onto the
+ * interface, based on __skb_tunnel_rx() in dst.h
+ */
+ skb->dev = peer->ovpn->dev;
+ skb_set_queue_mapping(skb, 0);
+ skb_scrub_packet(skb, true);
+
+ skb_reset_network_header(skb);
+ skb_reset_transport_header(skb);
+ skb_reset_inner_headers(skb);
+
+ /* cause packet to be "received" by the interface */
+ pkt_len = skb->len;
+ ret = gro_cells_receive(&peer->ovpn->gro_cells, skb);
+ if (likely(ret == NET_RX_SUCCESS))
+ /* update RX stats with the size of decrypted packet */
+ dev_sw_netstats_rx_add(peer->ovpn->dev, pkt_len);
+}
+
+static void ovpn_decrypt_post(struct sk_buff *skb, int ret)
+{
+ struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;
+
+ if (unlikely(ret < 0))
+ goto drop;
+
+ ovpn_netdev_write(peer, skb);
+ /* skb is passed to upper layer - don't free it */
+ skb = NULL;
+drop:
+ if (unlikely(skb))
+ dev_core_stats_rx_dropped_inc(peer->ovpn->dev);
+ ovpn_peer_put(peer);
+ kfree_skb(skb);
+}
+
+/* RX path entry point: decrypt packet and forward it to the device */
+void ovpn_recv(struct ovpn_peer *peer, struct sk_buff *skb)
+{
+ ovpn_skb_cb(skb)->peer = peer;
+ ovpn_decrypt_post(skb, 0);
+}
+
static void ovpn_encrypt_post(struct sk_buff *skb, int ret)
{
struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;
diff --git a/drivers/net/ovpn/io.h b/drivers/net/ovpn/io.h
index afea5f81f5628dcb9afda9a78974bbf6f2101c13..1cfa66873a2d4840ce57e337f8b4e8143e8b8e79 100644
--- a/drivers/net/ovpn/io.h
+++ b/drivers/net/ovpn/io.h
@@ -21,4 +21,6 @@
netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev);
+void ovpn_recv(struct ovpn_peer *peer, struct sk_buff *skb);
+
#endif /* _NET_OVPN_OVPN_H_ */
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index e58739d82da54001a346c38e5c5a882589eb3801..82f675f7a49ab9c35ff9686136b949a870b61c06 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -11,6 +11,7 @@
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/inetdevice.h>
+#include <net/gro_cells.h>
#include <net/ip.h>
#include <net/rtnetlink.h>
#include <uapi/linux/if_arp.h>
@@ -21,10 +22,20 @@
#include "io.h"
#include "peer.h"
#include "proto.h"
+#include "udp.h"
static int ovpn_net_init(struct net_device *dev)
{
- return 0;
+ struct ovpn_priv *ovpn = netdev_priv(dev);
+
+ return gro_cells_init(&ovpn->gro_cells, dev);
+}
+
+static void ovpn_net_uninit(struct net_device *dev)
+{
+ struct ovpn_priv *ovpn = netdev_priv(dev);
+
+ gro_cells_destroy(&ovpn->gro_cells);
}
static int ovpn_net_open(struct net_device *dev)
@@ -50,6 +61,7 @@ static int ovpn_net_stop(struct net_device *dev)
static const struct net_device_ops ovpn_netdev_ops = {
.ndo_init = ovpn_net_init,
+ .ndo_uninit = ovpn_net_uninit,
.ndo_open = ovpn_net_open,
.ndo_stop = ovpn_net_stop,
.ndo_start_xmit = ovpn_net_xmit,
diff --git a/drivers/net/ovpn/ovpnpriv.h b/drivers/net/ovpn/ovpnpriv.h
index fae2682b424b03222a5ce881a4a1b4518a7ff311..9d0640e9c71e7fd494e3d9df155732bd5d82463e 100644
--- a/drivers/net/ovpn/ovpnpriv.h
+++ b/drivers/net/ovpn/ovpnpriv.h
@@ -10,6 +10,7 @@
#ifndef _NET_OVPN_OVPNSTRUCT_H_
#define _NET_OVPN_OVPNSTRUCT_H_
+#include <net/gro_cells.h>
#include <uapi/linux/if_link.h>
#include <uapi/linux/ovpn.h>
@@ -20,6 +21,7 @@
* @mode: device operation mode (i.e. p2p, mp, ..)
* @lock: protect this object
* @peer: in P2P mode, this is the only remote peer
+ * @gro_cells: pointer to the Generic Receive Offload cell
*/
struct ovpn_priv {
struct net_device *dev;
@@ -27,6 +29,7 @@ struct ovpn_priv {
enum ovpn_mode mode;
spinlock_t lock; /* protect writing to the ovpn_priv object */
struct ovpn_peer __rcu *peer;
+ struct gro_cells gro_cells;
};
#endif /* _NET_OVPN_OVPNSTRUCT_H_ */
diff --git a/drivers/net/ovpn/proto.h b/drivers/net/ovpn/proto.h
index 5f95a78bebd3702868ffeeab3ea4938e957d568c..591b97a9925fd9b91f996d6d591fac41b1aa6148 100644
--- a/drivers/net/ovpn/proto.h
+++ b/drivers/net/ovpn/proto.h
@@ -10,6 +10,11 @@
#ifndef _NET_OVPN_PROTO_H_
#define _NET_OVPN_PROTO_H_
+#include "main.h"
+
+#include <linux/bitfield.h>
+#include <linux/skbuff.h>
+
/* When the OpenVPN protocol is ran in AEAD mode, use
* the OpenVPN packet ID as the AEAD nonce:
*
@@ -34,5 +39,48 @@
#define OVPN_NONCE_WIRE_SIZE (OVPN_NONCE_SIZE - OVPN_NONCE_TAIL_SIZE)
#define OVPN_OPCODE_SIZE 4 /* DATA_V2 opcode size */
+#define OVPN_OPCODE_KEYID_MASK 0x07000000
+#define OVPN_OPCODE_PKTTYPE_MASK 0xF8000000
+#define OVPN_OPCODE_PEERID_MASK 0x00FFFFFF
+
+/* packet opcodes of interest to us */
+#define OVPN_DATA_V1 6 /* data channel v1 packet */
+#define OVPN_DATA_V2 9 /* data channel v2 packet */
+
+#define OVPN_PEER_ID_UNDEF 0x00FFFFFF
+
+/**
+ * ovpn_opcode_from_skb - extract OP code from skb at specified offset
+ * @skb: the packet to extract the OP code from
+ * @offset: the offset in the data buffer where the OP code is located
+ *
+ * Note: this function assumes that the skb head was pulled enough
+ * to access the first 4 bytes.
+ *
+ * Return: the OP code
+ */
+static inline u8 ovpn_opcode_from_skb(const struct sk_buff *skb, u16 offset)
+{
+ u32 opcode = be32_to_cpu(*(__be32 *)(skb->data + offset));
+
+ return FIELD_GET(OVPN_OPCODE_PKTTYPE_MASK, opcode);
+}
+
+/**
+ * ovpn_peer_id_from_skb - extract peer ID from skb at specified offset
+ * @skb: the packet to extract the OP code from
+ * @offset: the offset in the data buffer where the OP code is located
+ *
+ * Note: this function assumes that the skb head was pulled enough
+ * to access the first 4 bytes.
+ *
+ * Return: the peer ID
+ */
+static inline u32 ovpn_peer_id_from_skb(const struct sk_buff *skb, u16 offset)
+{
+ u32 opcode = be32_to_cpu(*(__be32 *)(skb->data + offset));
+
+ return FIELD_GET(OVPN_OPCODE_PEERID_MASK, opcode);
+}
-#endif /* _NET_OVPN_PROTO_H_ */
+#endif /* _NET_OVPN_OVPNPROTO_H_ */
diff --git a/drivers/net/ovpn/socket.c b/drivers/net/ovpn/socket.c
index a4a8686f2e2995dca163d5b96c6c897b86434967..6de1e8c85a3d35a5d4f179d595d2409aa34cdc01 100644
--- a/drivers/net/ovpn/socket.c
+++ b/drivers/net/ovpn/socket.c
@@ -23,8 +23,10 @@ static void ovpn_socket_release_kref(struct kref *kref)
struct ovpn_socket *sock = container_of(kref, struct ovpn_socket,
refcount);
- if (sock->sock->sk->sk_protocol == IPPROTO_UDP)
+ if (sock->sock->sk->sk_protocol == IPPROTO_UDP) {
ovpn_udp_socket_detach(sock);
+ netdev_put(sock->ovpn->dev, &sock->dev_tracker);
+ }
kfree_rcu(sock, rcu);
}
@@ -200,6 +202,15 @@ struct ovpn_socket *ovpn_socket_new(struct socket *sock, struct ovpn_peer *peer)
goto sock_release;
}
+ if (sock->sk->sk_protocol == IPPROTO_UDP) {
+ /* in UDP we only link the ovpn instance since the socket is
+ * shared among multiple peers
+ */
+ ovpn_sock->ovpn = peer->ovpn;
+ netdev_hold(peer->ovpn->dev, &ovpn_sock->dev_tracker,
+ GFP_KERNEL);
+ }
+
rcu_assign_sk_user_data(sock->sk, ovpn_sock);
sock_release:
release_sock(sock->sk);
diff --git a/drivers/net/ovpn/socket.h b/drivers/net/ovpn/socket.h
index ade8c94619d7b2f905b5284373dc73f590188399..c1697f4616d470f143cba77bb1db34de0398a37a 100644
--- a/drivers/net/ovpn/socket.h
+++ b/drivers/net/ovpn/socket.h
@@ -20,12 +20,19 @@ struct ovpn_peer;
/**
* struct ovpn_socket - a kernel socket referenced in the ovpn code
* @ovpn: ovpn instance owning this socket (UDP only)
+ * @dev_tracker: reference tracker for associated dev (UDP only)
* @sock: the low level sock object
* @refcount: amount of contexts currently referencing this object
* @rcu: member used to schedule RCU destructor callback
*/
struct ovpn_socket {
- struct ovpn_priv *ovpn;
+ union {
+ struct {
+ struct ovpn_priv *ovpn;
+ netdevice_tracker dev_tracker;
+ };
+ };
+
struct socket *sock;
struct kref refcount;
struct rcu_head rcu;
diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c
index ae76ae6d372f565715a39ee24e3fba14f1c1370e..6f4b51089033a8d806eede0a63f62b239197af0b 100644
--- a/drivers/net/ovpn/udp.c
+++ b/drivers/net/ovpn/udp.c
@@ -15,6 +15,7 @@
#include <net/dst_cache.h>
#include <net/route.h>
#include <net/ipv6_stubs.h>
+#include <net/transp_v6.h>
#include <net/udp.h>
#include <net/udp_tunnel.h>
@@ -23,9 +24,114 @@
#include "bind.h"
#include "io.h"
#include "peer.h"
+#include "proto.h"
#include "socket.h"
#include "udp.h"
+/* Retrieve the corresponding ovpn object from a UDP socket
+ * rcu_read_lock must be held on entry
+ */
+static struct ovpn_socket *ovpn_socket_from_udp_sock(struct sock *sk)
+{
+ struct ovpn_socket *ovpn_sock;
+
+ if (unlikely(READ_ONCE(udp_sk(sk)->encap_type) != UDP_ENCAP_OVPNINUDP))
+ return NULL;
+
+ ovpn_sock = rcu_dereference_sk_user_data(sk);
+ if (unlikely(!ovpn_sock))
+ return NULL;
+
+ /* make sure that sk matches our stored transport socket */
+ if (unlikely(!ovpn_sock->sock || sk != ovpn_sock->sock->sk))
+ return NULL;
+
+ return ovpn_sock;
+}
+
+/**
+ * ovpn_udp_encap_recv - Start processing a received UDP packet.
+ * @sk: socket over which the packet was received
+ * @skb: the received packet
+ *
+ * If the first byte of the payload is:
+ * - DATA_V2 the packet is accepted for further processing,
+ * - DATA_V1 the packet is dropped as not supported,
+ * - anything else the packet is forwarded to the UDP stack for
+ * delivery to user space.
+ *
+ * Return:
+ * 0 if skb was consumed or dropped
+ * >0 if skb should be passed up to userspace as UDP (packet not consumed)
+ * <0 if skb should be resubmitted as proto -N (packet not consumed)
+ */
+static int ovpn_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
+{
+ struct ovpn_socket *ovpn_sock;
+ struct ovpn_priv *ovpn;
+ struct ovpn_peer *peer;
+ u32 peer_id;
+ u8 opcode;
+
+ ovpn_sock = ovpn_socket_from_udp_sock(sk);
+ if (unlikely(!ovpn_sock)) {
+ net_err_ratelimited("ovpn: %s invoked on non ovpn socket\n",
+ __func__);
+ goto drop_noovpn;
+ }
+
+ ovpn = ovpn_sock->ovpn;
+ if (unlikely(!ovpn)) {
+ net_err_ratelimited("ovpn: cannot obtain ovpn object from UDP socket\n");
+ goto drop_noovpn;
+ }
+
+ /* Make sure the first 4 bytes of the skb data buffer after the UDP
+ * header are accessible.
+ * They are required to fetch the OP code, the key ID and the peer ID.
+ */
+ if (unlikely(!pskb_may_pull(skb, sizeof(struct udphdr) +
+ OVPN_OPCODE_SIZE))) {
+ net_dbg_ratelimited("%s: packet too small from UDP socket\n",
+ netdev_name(ovpn->dev));
+ goto drop;
+ }
+
+ opcode = ovpn_opcode_from_skb(skb, sizeof(struct udphdr));
+ if (unlikely(opcode != OVPN_DATA_V2)) {
+ /* DATA_V1 is not supported */
+ if (opcode == OVPN_DATA_V1)
+ goto drop;
+
+ /* unknown or control packet: let it bubble up to userspace */
+ return 1;
+ }
+
+ peer_id = ovpn_peer_id_from_skb(skb, sizeof(struct udphdr));
+ /* some OpenVPN server implementations send data packets with the
+ * peer-id set to UNDEF. In this case we skip the peer lookup by peer-id
+ * and we try with the transport address
+ */
+ if (peer_id == OVPN_PEER_ID_UNDEF)
+ peer = ovpn_peer_get_by_transp_addr(ovpn, skb);
+ else
+ peer = ovpn_peer_get_by_id(ovpn, peer_id);
+
+ if (unlikely(!peer))
+ goto drop;
+
+ /* pop off outer UDP header */
+ __skb_pull(skb, sizeof(struct udphdr));
+ ovpn_recv(peer, skb);
+ return 0;
+
+drop:
+ dev_core_stats_rx_dropped_inc(ovpn->dev);
+drop_noovpn:
+ kfree_skb(skb);
+ return 0;
+}
+
/**
* ovpn_udp4_output - send IPv4 packet over udp socket
* @peer: the destination peer
@@ -250,6 +356,25 @@ void ovpn_udp_send_skb(struct ovpn_peer *peer, struct socket *sock,
}
}
+static void ovpn_udp_encap_destroy(struct sock *sk)
+{
+ struct ovpn_socket *sock;
+ struct ovpn_priv *ovpn;
+
+ rcu_read_lock();
+ sock = rcu_dereference_sk_user_data(sk);
+ if (!sock || !sock->ovpn) {
+ rcu_read_unlock();
+ return;
+ }
+ ovpn = sock->ovpn;
+ rcu_read_unlock();
+
+ if (ovpn->mode == OVPN_MODE_P2P)
+ ovpn_peer_release_p2p(ovpn, sk,
+ OVPN_DEL_PEER_REASON_TRANSPORT_DISCONNECT);
+}
+
/**
* ovpn_udp_socket_attach - set udp-tunnel CBs on socket and link it to ovpn
* @ovpn_sock: socket to configure
@@ -263,6 +388,11 @@ void ovpn_udp_send_skb(struct ovpn_peer *peer, struct socket *sock,
int ovpn_udp_socket_attach(struct ovpn_socket *ovpn_sock,
struct ovpn_priv *ovpn)
{
+ struct udp_tunnel_sock_cfg cfg = {
+ .encap_type = UDP_ENCAP_OVPNINUDP,
+ .encap_rcv = ovpn_udp_encap_recv,
+ .encap_destroy = ovpn_udp_encap_destroy,
+ };
struct socket *sock = ovpn_sock->sock;
struct ovpn_socket *old_data;
int ret;
@@ -273,6 +403,7 @@ int ovpn_udp_socket_attach(struct ovpn_socket *ovpn_sock,
if (!old_data) {
/* socket is currently unused - we can take it */
rcu_read_unlock();
+ setup_udp_tunnel_sock(sock_net(sock->sk), sock, &cfg);
return 0;
}
@@ -306,4 +437,8 @@ int ovpn_udp_socket_attach(struct ovpn_socket *ovpn_sock,
*/
void ovpn_udp_socket_detach(struct ovpn_socket *ovpn_sock)
{
+ struct udp_tunnel_sock_cfg cfg = { };
+
+ setup_udp_tunnel_sock(sock_net(ovpn_sock->sock->sk), ovpn_sock->sock,
+ &cfg);
}
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 3a0d6c5a8286b1685e8a1dec50365fe392ab9a87..8793b27273d6004dc3e9fbd459a076be822bdfea 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1933,6 +1933,7 @@ struct proto udpv6_prot = {
.h.udp_table = NULL,
.diag_destroy = udp_abort,
};
+EXPORT_SYMBOL_GPL(udpv6_prot);
static struct inet_protosw udpv6_protosw = {
.type = SOCK_DGRAM,
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 09/24] ovpn: implement packet processing
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (7 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 08/24] ovpn: implement basic RX " Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 19:02 ` Sabrina Dubroca
2025-03-04 0:33 ` [PATCH v21 10/24] ovpn: store tunnel and transport statistics Antonio Quartulli
` (14 subsequent siblings)
23 siblings, 1 reply; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
This change implements encryption/decryption and
encapsulation/decapsulation of OpenVPN packets.
Support for generic crypto state is added along with
a wrapper for the AEAD crypto kernel API.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/Kconfig | 4 +
drivers/net/ovpn/Makefile | 3 +
drivers/net/ovpn/bind.c | 9 +-
drivers/net/ovpn/crypto.c | 152 ++++++++++++++++
drivers/net/ovpn/crypto.h | 139 +++++++++++++++
drivers/net/ovpn/crypto_aead.c | 391 +++++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/crypto_aead.h | 31 ++++
drivers/net/ovpn/io.c | 156 ++++++++++++++--
drivers/net/ovpn/io.h | 3 +
drivers/net/ovpn/peer.c | 29 +++
drivers/net/ovpn/peer.h | 5 +
drivers/net/ovpn/pktid.c | 129 ++++++++++++++
drivers/net/ovpn/pktid.h | 87 +++++++++
drivers/net/ovpn/proto.h | 32 ++++
drivers/net/ovpn/skb.h | 5 +
15 files changed, 1158 insertions(+), 17 deletions(-)
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index b18ff941944e2e92aa769d1ebbc3d1782611fc06..51d77f3c0848c3c9425b586c6a90cff99a744390 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -121,6 +121,10 @@ config OVPN
depends on IPV6 || !IPV6
select DST_CACHE
select NET_UDP_TUNNEL
+ select CRYPTO
+ select CRYPTO_AES
+ select CRYPTO_GCM
+ select CRYPTO_CHACHA20POLY1305
help
This module enhances the performance of the OpenVPN userspace software
by offloading the data channel processing to kernelspace.
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
index 164f2058ea8e6dc5b9287afb59758a268b2f8b56..38c9fdca0e2e8e4af3c369ceb3971b58ab52d77b 100644
--- a/drivers/net/ovpn/Makefile
+++ b/drivers/net/ovpn/Makefile
@@ -8,10 +8,13 @@
obj-$(CONFIG_OVPN) := ovpn.o
ovpn-y += bind.o
+ovpn-y += crypto.o
+ovpn-y += crypto_aead.o
ovpn-y += main.o
ovpn-y += io.o
ovpn-y += netlink.o
ovpn-y += netlink-gen.o
ovpn-y += peer.o
+ovpn-y += pktid.o
ovpn-y += socket.o
ovpn-y += udp.o
diff --git a/drivers/net/ovpn/bind.c b/drivers/net/ovpn/bind.c
index d4a1aeed12c99c71eaf5e8e9fc9c0fe61af6aaac..24d2788a277e674bde80b5aac9407c6528b108e5 100644
--- a/drivers/net/ovpn/bind.c
+++ b/drivers/net/ovpn/bind.c
@@ -48,11 +48,8 @@ struct ovpn_bind *ovpn_bind_from_sockaddr(const struct sockaddr_storage *ss)
*/
void ovpn_bind_reset(struct ovpn_peer *peer, struct ovpn_bind *new)
{
- struct ovpn_bind *old;
+ lockdep_assert_held(&peer->lock);
- spin_lock_bh(&peer->lock);
- old = rcu_replace_pointer(peer->bind, new, true);
- spin_unlock_bh(&peer->lock);
-
- kfree_rcu(old, rcu);
+ kfree_rcu(rcu_replace_pointer(peer->bind, new,
+ lockdep_is_held(&peer->lock)), rcu);
}
diff --git a/drivers/net/ovpn/crypto.c b/drivers/net/ovpn/crypto.c
new file mode 100644
index 0000000000000000000000000000000000000000..ac15aaa9844083328020fcc5ea6866e08ecbc184
--- /dev/null
+++ b/drivers/net/ovpn/crypto.c
@@ -0,0 +1,152 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/types.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <uapi/linux/ovpn.h>
+
+#include "ovpnpriv.h"
+#include "main.h"
+#include "pktid.h"
+#include "crypto_aead.h"
+#include "crypto.h"
+
+static void ovpn_ks_destroy_rcu(struct rcu_head *head)
+{
+ struct ovpn_crypto_key_slot *ks;
+
+ ks = container_of(head, struct ovpn_crypto_key_slot, rcu);
+ ovpn_aead_crypto_key_slot_destroy(ks);
+}
+
+void ovpn_crypto_key_slot_release(struct kref *kref)
+{
+ struct ovpn_crypto_key_slot *ks;
+
+ ks = container_of(kref, struct ovpn_crypto_key_slot, refcount);
+ call_rcu(&ks->rcu, ovpn_ks_destroy_rcu);
+}
+
+/* can only be invoked when all peer references have been dropped (i.e. RCU
+ * release routine)
+ */
+void ovpn_crypto_state_release(struct ovpn_crypto_state *cs)
+{
+ struct ovpn_crypto_key_slot *ks;
+
+ ks = rcu_access_pointer(cs->slots[0]);
+ if (ks) {
+ RCU_INIT_POINTER(cs->slots[0], NULL);
+ ovpn_crypto_key_slot_put(ks);
+ }
+
+ ks = rcu_access_pointer(cs->slots[1]);
+ if (ks) {
+ RCU_INIT_POINTER(cs->slots[1], NULL);
+ ovpn_crypto_key_slot_put(ks);
+ }
+}
+
+/* Reset the ovpn_crypto_state object in a way that is atomic
+ * to RCU readers.
+ */
+int ovpn_crypto_state_reset(struct ovpn_crypto_state *cs,
+ const struct ovpn_peer_key_reset *pkr)
+{
+ struct ovpn_crypto_key_slot *old = NULL, *new;
+ u8 idx;
+
+ if (pkr->slot != OVPN_KEY_SLOT_PRIMARY &&
+ pkr->slot != OVPN_KEY_SLOT_SECONDARY)
+ return -EINVAL;
+
+ new = ovpn_aead_crypto_key_slot_new(&pkr->key);
+ if (IS_ERR(new))
+ return PTR_ERR(new);
+
+ spin_lock_bh(&cs->lock);
+ idx = cs->primary_idx;
+ switch (pkr->slot) {
+ case OVPN_KEY_SLOT_PRIMARY:
+ old = rcu_replace_pointer(cs->slots[idx], new,
+ lockdep_is_held(&cs->lock));
+ break;
+ case OVPN_KEY_SLOT_SECONDARY:
+ old = rcu_replace_pointer(cs->slots[!idx], new,
+ lockdep_is_held(&cs->lock));
+ break;
+ }
+ spin_unlock_bh(&cs->lock);
+
+ if (old)
+ ovpn_crypto_key_slot_put(old);
+
+ return 0;
+}
+
+void ovpn_crypto_key_slot_delete(struct ovpn_crypto_state *cs,
+ enum ovpn_key_slot slot)
+{
+ struct ovpn_crypto_key_slot *ks = NULL;
+ u8 idx;
+
+ if (slot != OVPN_KEY_SLOT_PRIMARY &&
+ slot != OVPN_KEY_SLOT_SECONDARY) {
+ pr_warn("Invalid slot to release: %u\n", slot);
+ return;
+ }
+
+ spin_lock_bh(&cs->lock);
+ idx = cs->primary_idx;
+ switch (slot) {
+ case OVPN_KEY_SLOT_PRIMARY:
+ ks = rcu_replace_pointer(cs->slots[idx], NULL,
+ lockdep_is_held(&cs->lock));
+ break;
+ case OVPN_KEY_SLOT_SECONDARY:
+ ks = rcu_replace_pointer(cs->slots[!idx], NULL,
+ lockdep_is_held(&cs->lock));
+ break;
+ }
+ spin_unlock_bh(&cs->lock);
+
+ if (!ks) {
+ pr_debug("Key slot already released: %u\n", slot);
+ return;
+ }
+
+ pr_debug("deleting key slot %u, key_id=%u\n", slot, ks->key_id);
+ ovpn_crypto_key_slot_put(ks);
+}
+
+/* this swap is not atomic, but there will be a very short time frame where the
+ * old_secondary key won't be available. This should not be a big deal as most
+ * likely both peers are already using the new primary at this point.
+ */
+void ovpn_crypto_key_slots_swap(struct ovpn_crypto_state *cs)
+{
+ const struct ovpn_crypto_key_slot *old_primary, *old_secondary;
+ u8 idx;
+
+ spin_lock_bh(&cs->lock);
+ idx = cs->primary_idx;
+ old_primary = rcu_dereference_protected(cs->slots[idx],
+ lockdep_is_held(&cs->lock));
+ old_secondary = rcu_dereference_protected(cs->slots[!idx],
+ lockdep_is_held(&cs->lock));
+ /* perform real swap by switching the index of the primary key */
+ cs->primary_idx = !cs->primary_idx;
+
+ pr_debug("key swapped: (old primary) %d <-> (new primary) %d\n",
+ old_primary ? old_primary->key_id : -1,
+ old_secondary ? old_secondary->key_id : -1);
+
+ spin_unlock_bh(&cs->lock);
+}
diff --git a/drivers/net/ovpn/crypto.h b/drivers/net/ovpn/crypto.h
new file mode 100644
index 0000000000000000000000000000000000000000..f3b3be9866df910e3d68762377505f65c767a4fe
--- /dev/null
+++ b/drivers/net/ovpn/crypto.h
@@ -0,0 +1,139 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_OVPNCRYPTO_H_
+#define _NET_OVPN_OVPNCRYPTO_H_
+
+#include "pktid.h"
+#include "proto.h"
+
+/* info needed for both encrypt and decrypt directions */
+struct ovpn_key_direction {
+ const u8 *cipher_key;
+ size_t cipher_key_size;
+ const u8 *nonce_tail; /* only needed for GCM modes */
+ size_t nonce_tail_size; /* only needed for GCM modes */
+};
+
+/* all info for a particular symmetric key (primary or secondary) */
+struct ovpn_key_config {
+ enum ovpn_cipher_alg cipher_alg;
+ u8 key_id;
+ struct ovpn_key_direction encrypt;
+ struct ovpn_key_direction decrypt;
+};
+
+/* used to pass settings from netlink to the crypto engine */
+struct ovpn_peer_key_reset {
+ enum ovpn_key_slot slot;
+ struct ovpn_key_config key;
+};
+
+struct ovpn_crypto_key_slot {
+ u8 key_id;
+
+ struct crypto_aead *encrypt;
+ struct crypto_aead *decrypt;
+ u8 nonce_tail_xmit[OVPN_NONCE_TAIL_SIZE];
+ u8 nonce_tail_recv[OVPN_NONCE_TAIL_SIZE];
+
+ struct ovpn_pktid_recv pid_recv ____cacheline_aligned_in_smp;
+ struct ovpn_pktid_xmit pid_xmit ____cacheline_aligned_in_smp;
+ struct kref refcount;
+ struct rcu_head rcu;
+};
+
+struct ovpn_crypto_state {
+ struct ovpn_crypto_key_slot __rcu *slots[2];
+ u8 primary_idx;
+
+ /* protects primary and secondary slots */
+ spinlock_t lock;
+};
+
+static inline bool ovpn_crypto_key_slot_hold(struct ovpn_crypto_key_slot *ks)
+{
+ return kref_get_unless_zero(&ks->refcount);
+}
+
+static inline void ovpn_crypto_state_init(struct ovpn_crypto_state *cs)
+{
+ RCU_INIT_POINTER(cs->slots[0], NULL);
+ RCU_INIT_POINTER(cs->slots[1], NULL);
+ cs->primary_idx = 0;
+ spin_lock_init(&cs->lock);
+}
+
+static inline struct ovpn_crypto_key_slot *
+ovpn_crypto_key_id_to_slot(const struct ovpn_crypto_state *cs, u8 key_id)
+{
+ struct ovpn_crypto_key_slot *ks;
+ u8 idx;
+
+ if (unlikely(!cs))
+ return NULL;
+
+ rcu_read_lock();
+ idx = cs->primary_idx;
+ ks = rcu_dereference(cs->slots[idx]);
+ if (ks && ks->key_id == key_id) {
+ if (unlikely(!ovpn_crypto_key_slot_hold(ks)))
+ ks = NULL;
+ goto out;
+ }
+
+ ks = rcu_dereference(cs->slots[!idx]);
+ if (ks && ks->key_id == key_id) {
+ if (unlikely(!ovpn_crypto_key_slot_hold(ks)))
+ ks = NULL;
+ goto out;
+ }
+
+ /* when both key slots are occupied but no matching key ID is found, ks
+ * has to be reset to NULL to avoid carrying a stale pointer
+ */
+ ks = NULL;
+out:
+ rcu_read_unlock();
+
+ return ks;
+}
+
+static inline struct ovpn_crypto_key_slot *
+ovpn_crypto_key_slot_primary(const struct ovpn_crypto_state *cs)
+{
+ struct ovpn_crypto_key_slot *ks;
+
+ rcu_read_lock();
+ ks = rcu_dereference(cs->slots[cs->primary_idx]);
+ if (unlikely(ks && !ovpn_crypto_key_slot_hold(ks)))
+ ks = NULL;
+ rcu_read_unlock();
+
+ return ks;
+}
+
+void ovpn_crypto_key_slot_release(struct kref *kref);
+
+static inline void ovpn_crypto_key_slot_put(struct ovpn_crypto_key_slot *ks)
+{
+ kref_put(&ks->refcount, ovpn_crypto_key_slot_release);
+}
+
+int ovpn_crypto_state_reset(struct ovpn_crypto_state *cs,
+ const struct ovpn_peer_key_reset *pkr);
+
+void ovpn_crypto_key_slot_delete(struct ovpn_crypto_state *cs,
+ enum ovpn_key_slot slot);
+
+void ovpn_crypto_state_release(struct ovpn_crypto_state *cs);
+
+void ovpn_crypto_key_slots_swap(struct ovpn_crypto_state *cs);
+
+#endif /* _NET_OVPN_OVPNCRYPTO_H_ */
diff --git a/drivers/net/ovpn/crypto_aead.c b/drivers/net/ovpn/crypto_aead.c
new file mode 100644
index 0000000000000000000000000000000000000000..ac678f087451da66bc39148902db21045a94eb19
--- /dev/null
+++ b/drivers/net/ovpn/crypto_aead.c
@@ -0,0 +1,391 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <crypto/aead.h>
+#include <linux/skbuff.h>
+#include <net/ip.h>
+#include <net/ipv6.h>
+#include <net/udp.h>
+
+#include "ovpnpriv.h"
+#include "main.h"
+#include "io.h"
+#include "pktid.h"
+#include "crypto_aead.h"
+#include "crypto.h"
+#include "peer.h"
+#include "proto.h"
+#include "skb.h"
+
+#define OVPN_AUTH_TAG_SIZE 16
+#define OVPN_AAD_SIZE (OVPN_OPCODE_SIZE + OVPN_NONCE_WIRE_SIZE)
+
+#define ALG_NAME_AES "gcm(aes)"
+#define ALG_NAME_CHACHAPOLY "rfc7539(chacha20,poly1305)"
+
+static int ovpn_aead_encap_overhead(const struct ovpn_crypto_key_slot *ks)
+{
+ return OVPN_OPCODE_SIZE + /* OP header size */
+ sizeof(u32) + /* Packet ID */
+ crypto_aead_authsize(ks->encrypt); /* Auth Tag */
+}
+
+int ovpn_aead_encrypt(struct ovpn_peer *peer, struct ovpn_crypto_key_slot *ks,
+ struct sk_buff *skb)
+{
+ const unsigned int tag_size = crypto_aead_authsize(ks->encrypt);
+ struct aead_request *req;
+ struct sk_buff *trailer;
+ struct scatterlist *sg;
+ int nfrags, ret;
+ u32 pktid, op;
+ u8 *iv;
+
+ ovpn_skb_cb(skb)->peer = peer;
+ ovpn_skb_cb(skb)->ks = ks;
+
+ /* Sample AEAD header format:
+ * 48000001 00000005 7e7046bd 444a7e28 cc6387b1 64a4d6c1 380275a...
+ * [ OP32 ] [seq # ] [ auth tag ] [ payload ... ]
+ * [4-byte
+ * IV head]
+ */
+
+ /* check that there's enough headroom in the skb for packet
+ * encapsulation
+ */
+ if (unlikely(skb_cow_head(skb, OVPN_HEAD_ROOM)))
+ return -ENOBUFS;
+
+ /* get number of skb frags and ensure that packet data is writable */
+ nfrags = skb_cow_data(skb, 0, &trailer);
+ if (unlikely(nfrags < 0))
+ return nfrags;
+
+ if (unlikely(nfrags + 2 > (MAX_SKB_FRAGS + 2)))
+ return -ENOSPC;
+
+ /* sg may be required by async crypto */
+ ovpn_skb_cb(skb)->sg = kmalloc(sizeof(*ovpn_skb_cb(skb)->sg) *
+ (nfrags + 2), GFP_ATOMIC);
+ if (unlikely(!ovpn_skb_cb(skb)->sg))
+ return -ENOMEM;
+
+ sg = ovpn_skb_cb(skb)->sg;
+
+ /* sg table:
+ * 0: op, wire nonce (AD, len=OVPN_OP_SIZE_V2+OVPN_NONCE_WIRE_SIZE),
+ * 1, 2, 3, ..., n: payload,
+ * n+1: auth_tag (len=tag_size)
+ */
+ sg_init_table(sg, nfrags + 2);
+
+ /* build scatterlist to encrypt packet payload */
+ ret = skb_to_sgvec_nomark(skb, sg + 1, 0, skb->len);
+ if (unlikely(nfrags != ret)) {
+ ret = -EINVAL;
+ goto free_sg;
+ }
+
+ /* append auth_tag onto scatterlist */
+ __skb_push(skb, tag_size);
+ sg_set_buf(sg + nfrags + 1, skb->data, tag_size);
+
+ /* obtain packet ID, which is used both as a first
+ * 4 bytes of nonce and last 4 bytes of associated data.
+ */
+ ret = ovpn_pktid_xmit_next(&ks->pid_xmit, &pktid);
+ if (unlikely(ret < 0))
+ goto free_sg;
+
+ /* iv may be required by async crypto */
+ ovpn_skb_cb(skb)->iv = kmalloc(OVPN_NONCE_SIZE, GFP_ATOMIC);
+ if (unlikely(!ovpn_skb_cb(skb)->iv)) {
+ ret = -ENOMEM;
+ goto free_sg;
+ }
+
+ iv = ovpn_skb_cb(skb)->iv;
+
+ /* concat 4 bytes packet id and 8 bytes nonce tail into 12 bytes
+ * nonce
+ */
+ ovpn_pktid_aead_write(pktid, ks->nonce_tail_xmit, iv);
+
+ /* make space for packet id and push it to the front */
+ __skb_push(skb, OVPN_NONCE_WIRE_SIZE);
+ memcpy(skb->data, iv, OVPN_NONCE_WIRE_SIZE);
+
+ /* add packet op as head of additional data */
+ op = ovpn_opcode_compose(OVPN_DATA_V2, ks->key_id, peer->id);
+ __skb_push(skb, OVPN_OPCODE_SIZE);
+ BUILD_BUG_ON(sizeof(op) != OVPN_OPCODE_SIZE);
+ *((__force __be32 *)skb->data) = htonl(op);
+
+ /* AEAD Additional data */
+ sg_set_buf(sg, skb->data, OVPN_AAD_SIZE);
+
+ req = aead_request_alloc(ks->encrypt, GFP_ATOMIC);
+ if (unlikely(!req)) {
+ ret = -ENOMEM;
+ goto free_iv;
+ }
+
+ ovpn_skb_cb(skb)->req = req;
+
+ /* setup async crypto operation */
+ aead_request_set_tfm(req, ks->encrypt);
+ aead_request_set_callback(req, 0, ovpn_encrypt_post, skb);
+ aead_request_set_crypt(req, sg, sg,
+ skb->len - ovpn_aead_encap_overhead(ks), iv);
+ aead_request_set_ad(req, OVPN_AAD_SIZE);
+
+ /* encrypt it */
+ return crypto_aead_encrypt(req);
+free_iv:
+ kfree(ovpn_skb_cb(skb)->iv);
+ ovpn_skb_cb(skb)->iv = NULL;
+free_sg:
+ kfree(ovpn_skb_cb(skb)->sg);
+ ovpn_skb_cb(skb)->sg = NULL;
+ return ret;
+}
+
+int ovpn_aead_decrypt(struct ovpn_peer *peer, struct ovpn_crypto_key_slot *ks,
+ struct sk_buff *skb)
+{
+ const unsigned int tag_size = crypto_aead_authsize(ks->decrypt);
+ int ret, payload_len, nfrags;
+ unsigned int payload_offset;
+ struct aead_request *req;
+ struct sk_buff *trailer;
+ struct scatterlist *sg;
+ u8 *iv;
+
+ payload_offset = OVPN_AAD_SIZE + tag_size;
+ payload_len = skb->len - payload_offset;
+
+ ovpn_skb_cb(skb)->payload_offset = payload_offset;
+ ovpn_skb_cb(skb)->peer = peer;
+ ovpn_skb_cb(skb)->ks = ks;
+
+ /* sanity check on packet size, payload size must be >= 0 */
+ if (unlikely(payload_len < 0))
+ return -EINVAL;
+
+ /* Prepare the skb data buffer to be accessed up until the auth tag.
+ * This is required because this area is directly mapped into the sg
+ * list.
+ */
+ if (unlikely(!pskb_may_pull(skb, payload_offset)))
+ return -ENODATA;
+
+ /* get number of skb frags and ensure that packet data is writable */
+ nfrags = skb_cow_data(skb, 0, &trailer);
+ if (unlikely(nfrags < 0))
+ return nfrags;
+
+ if (unlikely(nfrags + 2 > (MAX_SKB_FRAGS + 2)))
+ return -ENOSPC;
+
+ /* sg may be required by async crypto */
+ ovpn_skb_cb(skb)->sg = kmalloc(sizeof(*ovpn_skb_cb(skb)->sg) *
+ (nfrags + 2), GFP_ATOMIC);
+ if (unlikely(!ovpn_skb_cb(skb)->sg))
+ return -ENOMEM;
+
+ sg = ovpn_skb_cb(skb)->sg;
+
+ /* sg table:
+ * 0: op, wire nonce (AD, len=OVPN_OPCODE_SIZE+OVPN_NONCE_WIRE_SIZE),
+ * 1, 2, 3, ..., n: payload,
+ * n+1: auth_tag (len=tag_size)
+ */
+ sg_init_table(sg, nfrags + 2);
+
+ /* packet op is head of additional data */
+ sg_set_buf(sg, skb->data, OVPN_AAD_SIZE);
+
+ /* build scatterlist to decrypt packet payload */
+ ret = skb_to_sgvec_nomark(skb, sg + 1, payload_offset, payload_len);
+ if (unlikely(nfrags != ret)) {
+ ret = -EINVAL;
+ goto free_sg;
+ }
+
+ /* append auth_tag onto scatterlist */
+ sg_set_buf(sg + nfrags + 1, skb->data + OVPN_AAD_SIZE, tag_size);
+
+ /* iv may be required by async crypto */
+ ovpn_skb_cb(skb)->iv = kmalloc(OVPN_NONCE_SIZE, GFP_ATOMIC);
+ if (unlikely(!ovpn_skb_cb(skb)->iv)) {
+ ret = -ENOMEM;
+ goto free_sg;
+ }
+
+ iv = ovpn_skb_cb(skb)->iv;
+
+ /* copy nonce into IV buffer */
+ memcpy(iv, skb->data + OVPN_OPCODE_SIZE, OVPN_NONCE_WIRE_SIZE);
+ memcpy(iv + OVPN_NONCE_WIRE_SIZE, ks->nonce_tail_recv,
+ OVPN_NONCE_TAIL_SIZE);
+
+ req = aead_request_alloc(ks->decrypt, GFP_ATOMIC);
+ if (unlikely(!req)) {
+ ret = -ENOMEM;
+ goto free_iv;
+ }
+
+ ovpn_skb_cb(skb)->req = req;
+
+ /* setup async crypto operation */
+ aead_request_set_tfm(req, ks->decrypt);
+ aead_request_set_callback(req, 0, ovpn_decrypt_post, skb);
+ aead_request_set_crypt(req, sg, sg, payload_len + tag_size, iv);
+
+ aead_request_set_ad(req, OVPN_AAD_SIZE);
+
+ /* decrypt it */
+ return crypto_aead_decrypt(req);
+free_iv:
+ kfree(ovpn_skb_cb(skb)->iv);
+ ovpn_skb_cb(skb)->iv = NULL;
+free_sg:
+ kfree(ovpn_skb_cb(skb)->sg);
+ ovpn_skb_cb(skb)->sg = NULL;
+ return ret;
+}
+
+/* Initialize a struct crypto_aead object */
+struct crypto_aead *ovpn_aead_init(const char *title, const char *alg_name,
+ const unsigned char *key,
+ unsigned int keylen)
+{
+ struct crypto_aead *aead;
+ int ret;
+
+ aead = crypto_alloc_aead(alg_name, 0, 0);
+ if (IS_ERR(aead)) {
+ ret = PTR_ERR(aead);
+ pr_err("%s crypto_alloc_aead failed, err=%d\n", title, ret);
+ aead = NULL;
+ goto error;
+ }
+
+ ret = crypto_aead_setkey(aead, key, keylen);
+ if (ret) {
+ pr_err("%s crypto_aead_setkey size=%u failed, err=%d\n", title,
+ keylen, ret);
+ goto error;
+ }
+
+ ret = crypto_aead_setauthsize(aead, OVPN_AUTH_TAG_SIZE);
+ if (ret) {
+ pr_err("%s crypto_aead_setauthsize failed, err=%d\n", title,
+ ret);
+ goto error;
+ }
+
+ /* basic AEAD assumption */
+ if (crypto_aead_ivsize(aead) != OVPN_NONCE_SIZE) {
+ pr_err("%s IV size must be %d\n", title, OVPN_NONCE_SIZE);
+ ret = -EINVAL;
+ goto error;
+ }
+
+ pr_debug("********* Cipher %s (%s)\n", alg_name, title);
+ pr_debug("*** IV size=%u\n", crypto_aead_ivsize(aead));
+ pr_debug("*** req size=%u\n", crypto_aead_reqsize(aead));
+ pr_debug("*** block size=%u\n", crypto_aead_blocksize(aead));
+ pr_debug("*** auth size=%u\n", crypto_aead_authsize(aead));
+ pr_debug("*** alignmask=0x%x\n", crypto_aead_alignmask(aead));
+
+ return aead;
+
+error:
+ crypto_free_aead(aead);
+ return ERR_PTR(ret);
+}
+
+void ovpn_aead_crypto_key_slot_destroy(struct ovpn_crypto_key_slot *ks)
+{
+ if (!ks)
+ return;
+
+ crypto_free_aead(ks->encrypt);
+ crypto_free_aead(ks->decrypt);
+ kfree(ks);
+}
+
+struct ovpn_crypto_key_slot *
+ovpn_aead_crypto_key_slot_new(const struct ovpn_key_config *kc)
+{
+ struct ovpn_crypto_key_slot *ks = NULL;
+ const char *alg_name;
+ int ret;
+
+ /* validate crypto alg */
+ switch (kc->cipher_alg) {
+ case OVPN_CIPHER_ALG_AES_GCM:
+ alg_name = ALG_NAME_AES;
+ break;
+ case OVPN_CIPHER_ALG_CHACHA20_POLY1305:
+ alg_name = ALG_NAME_CHACHAPOLY;
+ break;
+ default:
+ return ERR_PTR(-EOPNOTSUPP);
+ }
+
+ if (kc->encrypt.nonce_tail_size != OVPN_NONCE_TAIL_SIZE ||
+ kc->decrypt.nonce_tail_size != OVPN_NONCE_TAIL_SIZE)
+ return ERR_PTR(-EINVAL);
+
+ /* build the key slot */
+ ks = kmalloc(sizeof(*ks), GFP_KERNEL);
+ if (!ks)
+ return ERR_PTR(-ENOMEM);
+
+ ks->encrypt = NULL;
+ ks->decrypt = NULL;
+ kref_init(&ks->refcount);
+ ks->key_id = kc->key_id;
+
+ ks->encrypt = ovpn_aead_init("encrypt", alg_name,
+ kc->encrypt.cipher_key,
+ kc->encrypt.cipher_key_size);
+ if (IS_ERR(ks->encrypt)) {
+ ret = PTR_ERR(ks->encrypt);
+ ks->encrypt = NULL;
+ goto destroy_ks;
+ }
+
+ ks->decrypt = ovpn_aead_init("decrypt", alg_name,
+ kc->decrypt.cipher_key,
+ kc->decrypt.cipher_key_size);
+ if (IS_ERR(ks->decrypt)) {
+ ret = PTR_ERR(ks->decrypt);
+ ks->decrypt = NULL;
+ goto destroy_ks;
+ }
+
+ memcpy(ks->nonce_tail_xmit, kc->encrypt.nonce_tail,
+ OVPN_NONCE_TAIL_SIZE);
+ memcpy(ks->nonce_tail_recv, kc->decrypt.nonce_tail,
+ OVPN_NONCE_TAIL_SIZE);
+
+ /* init packet ID generation/validation */
+ ovpn_pktid_xmit_init(&ks->pid_xmit);
+ ovpn_pktid_recv_init(&ks->pid_recv);
+
+ return ks;
+
+destroy_ks:
+ ovpn_aead_crypto_key_slot_destroy(ks);
+ return ERR_PTR(ret);
+}
diff --git a/drivers/net/ovpn/crypto_aead.h b/drivers/net/ovpn/crypto_aead.h
new file mode 100644
index 0000000000000000000000000000000000000000..8a9d01f5eed700d2f7dfbbecbddbb370966682b9
--- /dev/null
+++ b/drivers/net/ovpn/crypto_aead.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_OVPNAEAD_H_
+#define _NET_OVPN_OVPNAEAD_H_
+
+#include "crypto.h"
+
+#include <asm/types.h>
+#include <linux/skbuff.h>
+
+struct crypto_aead *ovpn_aead_init(const char *title, const char *alg_name,
+ const unsigned char *key,
+ unsigned int keylen);
+
+int ovpn_aead_encrypt(struct ovpn_peer *peer, struct ovpn_crypto_key_slot *ks,
+ struct sk_buff *skb);
+int ovpn_aead_decrypt(struct ovpn_peer *peer, struct ovpn_crypto_key_slot *ks,
+ struct sk_buff *skb);
+
+struct ovpn_crypto_key_slot *
+ovpn_aead_crypto_key_slot_new(const struct ovpn_key_config *kc);
+void ovpn_aead_crypto_key_slot_destroy(struct ovpn_crypto_key_slot *ks);
+
+#endif /* _NET_OVPN_OVPNAEAD_H_ */
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index 46ad27e8eb8425f810c7d2b6c63984ea008d90fa..d0b410535ac340a53f010d0b2f20430b26bb012d 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -7,6 +7,7 @@
* Antonio Quartulli <antonio@openvpn.net>
*/
+#include <crypto/aead.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <net/gro_cells.h>
@@ -15,6 +16,9 @@
#include "ovpnpriv.h"
#include "peer.h"
#include "io.h"
+#include "bind.h"
+#include "crypto.h"
+#include "crypto_aead.h"
#include "netlink.h"
#include "proto.h"
#include "udp.h"
@@ -44,7 +48,7 @@ static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb)
skb_set_queue_mapping(skb, 0);
skb_scrub_packet(skb, true);
- skb_reset_network_header(skb);
+ /* network header reset in ovpn_decrypt_post() */
skb_reset_transport_header(skb);
skb_reset_inner_headers(skb);
@@ -56,34 +60,147 @@ static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb)
dev_sw_netstats_rx_add(peer->ovpn->dev, pkt_len);
}
-static void ovpn_decrypt_post(struct sk_buff *skb, int ret)
+void ovpn_decrypt_post(void *data, int ret)
{
- struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;
+ struct ovpn_crypto_key_slot *ks;
+ unsigned int payload_offset = 0;
+ struct sk_buff *skb = data;
+ struct ovpn_peer *peer;
+ __be16 proto;
+ __be32 *pid;
+
+ /* crypto is happening asynchronously. this function will be called
+ * again later by the crypto callback with a proper return code
+ */
+ if (unlikely(ret == -EINPROGRESS))
+ return;
+
+ payload_offset = ovpn_skb_cb(skb)->payload_offset;
+ ks = ovpn_skb_cb(skb)->ks;
+ peer = ovpn_skb_cb(skb)->peer;
+
+ /* crypto is done, cleanup skb CB and its members */
+
+ if (likely(ovpn_skb_cb(skb)->iv))
+ kfree(ovpn_skb_cb(skb)->iv);
+
+ if (likely(ovpn_skb_cb(skb)->sg))
+ kfree(ovpn_skb_cb(skb)->sg);
+
+ if (likely(ovpn_skb_cb(skb)->req))
+ aead_request_free(ovpn_skb_cb(skb)->req);
if (unlikely(ret < 0))
goto drop;
+ /* PID sits after the op */
+ pid = (__force __be32 *)(skb->data + OVPN_OPCODE_SIZE);
+ ret = ovpn_pktid_recv(&ks->pid_recv, ntohl(*pid), 0);
+ if (unlikely(ret < 0)) {
+ net_err_ratelimited("%s: PKT ID RX error for peer %u: %d\n",
+ netdev_name(peer->ovpn->dev), peer->id,
+ ret);
+ goto drop;
+ }
+
+ /* point to encapsulated IP packet */
+ __skb_pull(skb, payload_offset);
+
+ /* check if this is a valid datapacket that has to be delivered to the
+ * ovpn interface
+ */
+ skb_reset_network_header(skb);
+ proto = ovpn_ip_check_protocol(skb);
+ if (unlikely(!proto)) {
+ /* check if null packet */
+ if (unlikely(!pskb_may_pull(skb, 1))) {
+ net_info_ratelimited("%s: NULL packet received from peer %u\n",
+ netdev_name(peer->ovpn->dev),
+ peer->id);
+ goto drop;
+ }
+
+ net_info_ratelimited("%s: unsupported protocol received from peer %u\n",
+ netdev_name(peer->ovpn->dev), peer->id);
+ goto drop;
+ }
+ skb->protocol = proto;
+
+ /* perform Reverse Path Filtering (RPF) */
+ if (unlikely(!ovpn_peer_check_by_src(peer->ovpn, skb, peer))) {
+ if (skb->protocol == htons(ETH_P_IPV6))
+ net_dbg_ratelimited("%s: RPF dropped packet from peer %u, src: %pI6c\n",
+ netdev_name(peer->ovpn->dev),
+ peer->id, &ipv6_hdr(skb)->saddr);
+ else
+ net_dbg_ratelimited("%s: RPF dropped packet from peer %u, src: %pI4\n",
+ netdev_name(peer->ovpn->dev),
+ peer->id, &ip_hdr(skb)->saddr);
+ goto drop;
+ }
+
ovpn_netdev_write(peer, skb);
/* skb is passed to upper layer - don't free it */
skb = NULL;
drop:
if (unlikely(skb))
dev_core_stats_rx_dropped_inc(peer->ovpn->dev);
- ovpn_peer_put(peer);
+ if (likely(peer))
+ ovpn_peer_put(peer);
+ if (likely(ks))
+ ovpn_crypto_key_slot_put(ks);
kfree_skb(skb);
}
/* RX path entry point: decrypt packet and forward it to the device */
void ovpn_recv(struct ovpn_peer *peer, struct sk_buff *skb)
{
- ovpn_skb_cb(skb)->peer = peer;
- ovpn_decrypt_post(skb, 0);
+ struct ovpn_crypto_key_slot *ks;
+ u8 key_id;
+
+ /* get the key slot matching the key ID in the received packet */
+ key_id = ovpn_key_id_from_skb(skb);
+ ks = ovpn_crypto_key_id_to_slot(&peer->crypto, key_id);
+ if (unlikely(!ks)) {
+ net_info_ratelimited("%s: no available key for peer %u, key-id: %u\n",
+ netdev_name(peer->ovpn->dev), peer->id,
+ key_id);
+ dev_core_stats_rx_dropped_inc(peer->ovpn->dev);
+ kfree_skb(skb);
+ ovpn_peer_put(peer);
+ return;
+ }
+
+ memset(ovpn_skb_cb(skb), 0, sizeof(struct ovpn_cb));
+ ovpn_decrypt_post(skb, ovpn_aead_decrypt(peer, ks, skb));
}
-static void ovpn_encrypt_post(struct sk_buff *skb, int ret)
+void ovpn_encrypt_post(void *data, int ret)
{
- struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;
+ struct ovpn_crypto_key_slot *ks;
+ struct sk_buff *skb = data;
struct ovpn_socket *sock;
+ struct ovpn_peer *peer;
+
+ /* encryption is happening asynchronously. This function will be
+ * called later by the crypto callback with a proper return value
+ */
+ if (unlikely(ret == -EINPROGRESS))
+ return;
+
+ ks = ovpn_skb_cb(skb)->ks;
+ peer = ovpn_skb_cb(skb)->peer;
+
+ /* crypto is done, cleanup skb CB and its members */
+
+ if (likely(ovpn_skb_cb(skb)->iv))
+ kfree(ovpn_skb_cb(skb)->iv);
+
+ if (likely(ovpn_skb_cb(skb)->sg))
+ kfree(ovpn_skb_cb(skb)->sg);
+
+ if (likely(ovpn_skb_cb(skb)->req))
+ aead_request_free(ovpn_skb_cb(skb)->req);
if (unlikely(ret < 0))
goto err;
@@ -110,23 +227,40 @@ static void ovpn_encrypt_post(struct sk_buff *skb, int ret)
err:
if (unlikely(skb))
dev_core_stats_tx_dropped_inc(peer->ovpn->dev);
- ovpn_peer_put(peer);
+ if (likely(peer))
+ ovpn_peer_put(peer);
+ if (likely(ks))
+ ovpn_crypto_key_slot_put(ks);
kfree_skb(skb);
}
static bool ovpn_encrypt_one(struct ovpn_peer *peer, struct sk_buff *skb)
{
- ovpn_skb_cb(skb)->peer = peer;
+ struct ovpn_crypto_key_slot *ks;
+
+ if (unlikely(skb->ip_summed == CHECKSUM_PARTIAL &&
+ skb_checksum_help(skb))) {
+ net_warn_ratelimited("%s: cannot compute checksum for outgoing packet for peer %u\n",
+ netdev_name(peer->ovpn->dev), peer->id);
+ return false;
+ }
+
+ /* get primary key to be used for encrypting data */
+ ks = ovpn_crypto_key_slot_primary(&peer->crypto);
+ if (unlikely(!ks))
+ return false;
/* take a reference to the peer because the crypto code may run async.
* ovpn_encrypt_post() will release it upon completion
*/
if (unlikely(!ovpn_peer_hold(peer))) {
DEBUG_NET_WARN_ON_ONCE(1);
+ ovpn_crypto_key_slot_put(ks);
return false;
}
- ovpn_encrypt_post(skb, 0);
+ memset(ovpn_skb_cb(skb), 0, sizeof(struct ovpn_cb));
+ ovpn_encrypt_post(skb, ovpn_aead_encrypt(peer, ks, skb));
return true;
}
diff --git a/drivers/net/ovpn/io.h b/drivers/net/ovpn/io.h
index 1cfa66873a2d4840ce57e337f8b4e8143e8b8e79..5143104b2c4b896a030ec4a8c8aea7015f40ef02 100644
--- a/drivers/net/ovpn/io.h
+++ b/drivers/net/ovpn/io.h
@@ -23,4 +23,7 @@ netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev);
void ovpn_recv(struct ovpn_peer *peer, struct sk_buff *skb);
+void ovpn_encrypt_post(void *data, int ret);
+void ovpn_decrypt_post(void *data, int ret);
+
#endif /* _NET_OVPN_OVPN_H_ */
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 10eabd62ae7237162a36a333b41c748901a7d888..23eaab1b465b8b88a84cf9f1039621923b640b47 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -12,6 +12,8 @@
#include "ovpnpriv.h"
#include "bind.h"
+#include "pktid.h"
+#include "crypto.h"
#include "io.h"
#include "main.h"
#include "netlink.h"
@@ -56,6 +58,7 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id)
peer->vpn_addrs.ipv6 = in6addr_any;
RCU_INIT_POINTER(peer->bind, NULL);
+ ovpn_crypto_state_init(&peer->crypto);
spin_lock_init(&peer->lock);
kref_init(&peer->refcount);
@@ -94,7 +97,10 @@ static void ovpn_peer_release_rcu(struct rcu_head *head)
*/
static void ovpn_peer_release(struct ovpn_peer *peer)
{
+ ovpn_crypto_state_release(&peer->crypto);
+ spin_lock_bh(&peer->lock);
ovpn_bind_reset(peer, NULL);
+ spin_unlock_bh(&peer->lock);
call_rcu(&peer->rcu, ovpn_peer_release_rcu);
netdev_put(peer->ovpn->dev, &peer->dev_tracker);
}
@@ -326,6 +332,29 @@ struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_priv *ovpn,
return peer;
}
+/**
+ * ovpn_peer_check_by_src - check that skb source is routed via peer
+ * @ovpn: the openvpn instance to search
+ * @skb: the packet to extract source address from
+ * @peer: the peer to check against the source address
+ *
+ * Return: true if the peer is matching or false otherwise
+ */
+bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb,
+ struct ovpn_peer *peer)
+{
+ bool match = false;
+
+ if (ovpn->mode == OVPN_MODE_P2P) {
+ /* in P2P mode, no matter the destination, packets are always
+ * sent to the single peer listening on the other side
+ */
+ match = (peer == rcu_access_pointer(ovpn->peer));
+ }
+
+ return match;
+}
+
/**
* ovpn_peer_add_p2p - add peer to related tables in a P2P instance
* @ovpn: the instance to add the peer to
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index fef04311c1593db4ccfa3c417487b3d4faaae9d7..a9113a969f94d66fa17208d563d0bbd255c23fa9 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -12,6 +12,7 @@
#include <net/dst_cache.h>
+#include "crypto.h"
#include "socket.h"
/**
@@ -23,6 +24,7 @@
* @vpn_addrs.ipv4: IPv4 assigned to peer on the tunnel
* @vpn_addrs.ipv6: IPv6 assigned to peer on the tunnel
* @sock: the socket being used to talk to this peer
+ * @crypto: the crypto configuration (ciphers, keys, etc..)
* @dst_cache: cache for dst_entry used to send to peer
* @bind: remote peer binding
* @delete_reason: why peer was deleted (i.e. timeout, transport error, ..)
@@ -40,6 +42,7 @@ struct ovpn_peer {
struct in6_addr ipv6;
} vpn_addrs;
struct ovpn_socket __rcu *sock;
+ struct ovpn_crypto_state crypto;
struct dst_cache dst_cache;
struct ovpn_bind __rcu *bind;
enum ovpn_del_peer_reason delete_reason;
@@ -82,5 +85,7 @@ struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_priv *ovpn,
struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_priv *ovpn, u32 peer_id);
struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_priv *ovpn,
struct sk_buff *skb);
+bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb,
+ struct ovpn_peer *peer);
#endif /* _NET_OVPN_OVPNPEER_H_ */
diff --git a/drivers/net/ovpn/pktid.c b/drivers/net/ovpn/pktid.c
new file mode 100644
index 0000000000000000000000000000000000000000..2e73d1c1ec8b6c4fe2fc10ebc1a4f3008362df21
--- /dev/null
+++ b/drivers/net/ovpn/pktid.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ * James Yonan <james@openvpn.net>
+ */
+
+#include <linux/atomic.h>
+#include <linux/jiffies.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/types.h>
+
+#include "ovpnpriv.h"
+#include "main.h"
+#include "pktid.h"
+
+void ovpn_pktid_xmit_init(struct ovpn_pktid_xmit *pid)
+{
+ atomic64_set(&pid->seq_num, 1);
+}
+
+void ovpn_pktid_recv_init(struct ovpn_pktid_recv *pr)
+{
+ memset(pr, 0, sizeof(*pr));
+ spin_lock_init(&pr->lock);
+}
+
+/* Packet replay detection.
+ * Allows ID backtrack of up to REPLAY_WINDOW_SIZE - 1.
+ */
+int ovpn_pktid_recv(struct ovpn_pktid_recv *pr, u32 pkt_id, u32 pkt_time)
+{
+ const unsigned long now = jiffies;
+ int ret;
+
+ /* ID must not be zero */
+ if (unlikely(pkt_id == 0))
+ return -EINVAL;
+
+ spin_lock_bh(&pr->lock);
+
+ /* expire backtracks at or below pr->id after PKTID_RECV_EXPIRE time */
+ if (unlikely(time_after_eq(now, pr->expire)))
+ pr->id_floor = pr->id;
+
+ /* time changed? */
+ if (unlikely(pkt_time != pr->time)) {
+ if (pkt_time > pr->time) {
+ /* time moved forward, accept */
+ pr->base = 0;
+ pr->extent = 0;
+ pr->id = 0;
+ pr->time = pkt_time;
+ pr->id_floor = 0;
+ } else {
+ /* time moved backward, reject */
+ ret = -ETIME;
+ goto out;
+ }
+ }
+
+ if (likely(pkt_id == pr->id + 1)) {
+ /* well-formed ID sequence (incremented by 1) */
+ pr->base = REPLAY_INDEX(pr->base, -1);
+ pr->history[pr->base / 8] |= (1 << (pr->base % 8));
+ if (pr->extent < REPLAY_WINDOW_SIZE)
+ ++pr->extent;
+ pr->id = pkt_id;
+ } else if (pkt_id > pr->id) {
+ /* ID jumped forward by more than one */
+ const unsigned int delta = pkt_id - pr->id;
+
+ if (delta < REPLAY_WINDOW_SIZE) {
+ unsigned int i;
+
+ pr->base = REPLAY_INDEX(pr->base, -delta);
+ pr->history[pr->base / 8] |= (1 << (pr->base % 8));
+ pr->extent += delta;
+ if (pr->extent > REPLAY_WINDOW_SIZE)
+ pr->extent = REPLAY_WINDOW_SIZE;
+ for (i = 1; i < delta; ++i) {
+ unsigned int newb = REPLAY_INDEX(pr->base, i);
+
+ pr->history[newb / 8] &= ~BIT(newb % 8);
+ }
+ } else {
+ pr->base = 0;
+ pr->extent = REPLAY_WINDOW_SIZE;
+ memset(pr->history, 0, sizeof(pr->history));
+ pr->history[0] = 1;
+ }
+ pr->id = pkt_id;
+ } else {
+ /* ID backtrack */
+ const unsigned int delta = pr->id - pkt_id;
+
+ if (delta > pr->max_backtrack)
+ pr->max_backtrack = delta;
+ if (delta < pr->extent) {
+ if (pkt_id > pr->id_floor) {
+ const unsigned int ri = REPLAY_INDEX(pr->base,
+ delta);
+ u8 *p = &pr->history[ri / 8];
+ const u8 mask = (1 << (ri % 8));
+
+ if (*p & mask) {
+ ret = -EINVAL;
+ goto out;
+ }
+ *p |= mask;
+ } else {
+ ret = -EINVAL;
+ goto out;
+ }
+ } else {
+ ret = -EINVAL;
+ goto out;
+ }
+ }
+
+ pr->expire = now + PKTID_RECV_EXPIRE;
+ ret = 0;
+out:
+ spin_unlock_bh(&pr->lock);
+ return ret;
+}
diff --git a/drivers/net/ovpn/pktid.h b/drivers/net/ovpn/pktid.h
new file mode 100644
index 0000000000000000000000000000000000000000..0e5fd91d488359f675f500a7368027f7a148f5c6
--- /dev/null
+++ b/drivers/net/ovpn/pktid.h
@@ -0,0 +1,87 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ * James Yonan <james@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_OVPNPKTID_H_
+#define _NET_OVPN_OVPNPKTID_H_
+
+#include "proto.h"
+
+/* If no packets received for this length of time, set a backtrack floor
+ * at highest received packet ID thus far.
+ */
+#define PKTID_RECV_EXPIRE (30 * HZ)
+
+/* Packet-ID state for transmitter */
+struct ovpn_pktid_xmit {
+ atomic64_t seq_num;
+};
+
+/* replay window sizing in bytes = 2^REPLAY_WINDOW_ORDER */
+#define REPLAY_WINDOW_ORDER 8
+
+#define REPLAY_WINDOW_BYTES BIT(REPLAY_WINDOW_ORDER)
+#define REPLAY_WINDOW_SIZE (REPLAY_WINDOW_BYTES * 8)
+#define REPLAY_INDEX(base, i) (((base) + (i)) & (REPLAY_WINDOW_SIZE - 1))
+
+/* Packet-ID state for receiver.
+ * Other than lock member, can be zeroed to initialize.
+ */
+struct ovpn_pktid_recv {
+ /* "sliding window" bitmask of recent packet IDs received */
+ u8 history[REPLAY_WINDOW_BYTES];
+ /* bit position of deque base in history */
+ unsigned int base;
+ /* extent (in bits) of deque in history */
+ unsigned int extent;
+ /* expiration of history in jiffies */
+ unsigned long expire;
+ /* highest sequence number received */
+ u32 id;
+ /* highest time stamp received */
+ u32 time;
+ /* we will only accept backtrack IDs > id_floor */
+ u32 id_floor;
+ unsigned int max_backtrack;
+ /* protects entire pktd ID state */
+ spinlock_t lock;
+};
+
+/* Get the next packet ID for xmit */
+static inline int ovpn_pktid_xmit_next(struct ovpn_pktid_xmit *pid, u32 *pktid)
+{
+ const s64 seq_num = atomic64_fetch_add_unless(&pid->seq_num, 1,
+ 0x100000000LL);
+ /* when the 32bit space is over, we return an error because the packet
+ * ID is used to create the cipher IV and we do not want to reuse the
+ * same value more than once
+ */
+ if (unlikely(seq_num == 0x100000000LL))
+ return -ERANGE;
+
+ *pktid = (u32)seq_num;
+
+ return 0;
+}
+
+/* Write 12-byte AEAD IV to dest */
+static inline void ovpn_pktid_aead_write(const u32 pktid,
+ const u8 nt[],
+ unsigned char *dest)
+{
+ *(__force __be32 *)(dest) = htonl(pktid);
+ BUILD_BUG_ON(4 + OVPN_NONCE_TAIL_SIZE != OVPN_NONCE_SIZE);
+ memcpy(dest + 4, nt, OVPN_NONCE_TAIL_SIZE);
+}
+
+void ovpn_pktid_xmit_init(struct ovpn_pktid_xmit *pid);
+void ovpn_pktid_recv_init(struct ovpn_pktid_recv *pr);
+
+int ovpn_pktid_recv(struct ovpn_pktid_recv *pr, u32 pkt_id, u32 pkt_time);
+
+#endif /* _NET_OVPN_OVPNPKTID_H_ */
diff --git a/drivers/net/ovpn/proto.h b/drivers/net/ovpn/proto.h
index 591b97a9925fd9b91f996d6d591fac41b1aa6148..b7322c7c515e5c0744719e11ca81fece3ca28569 100644
--- a/drivers/net/ovpn/proto.h
+++ b/drivers/net/ovpn/proto.h
@@ -83,4 +83,36 @@ static inline u32 ovpn_peer_id_from_skb(const struct sk_buff *skb, u16 offset)
return FIELD_GET(OVPN_OPCODE_PEERID_MASK, opcode);
}
+/**
+ * ovpn_key_id_from_skb - extract key ID from the skb head
+ * @skb: the packet to extract the key ID code from
+ *
+ * Note: this function assumes that the skb head was pulled enough
+ * to access the first byte.
+ *
+ * Return: the key ID
+ */
+static inline u8 ovpn_key_id_from_skb(const struct sk_buff *skb)
+{
+ u32 opcode = be32_to_cpu(*(__be32 *)skb->data);
+
+ return FIELD_GET(OVPN_OPCODE_KEYID_MASK, opcode);
+}
+
+/**
+ * ovpn_opcode_compose - combine OP code, key ID and peer ID to wire format
+ * @opcode: the OP code
+ * @key_id: the key ID
+ * @peer_id: the peer ID
+ *
+ * Return: a 4 bytes integer obtained combining all input values following the
+ * OpenVPN wire format. This integer can then be written to the packet header.
+ */
+static inline u32 ovpn_opcode_compose(u8 opcode, u8 key_id, u32 peer_id)
+{
+ return FIELD_PREP(OVPN_OPCODE_PKTTYPE_MASK, opcode) |
+ FIELD_PREP(OVPN_OPCODE_KEYID_MASK, key_id) |
+ FIELD_PREP(OVPN_OPCODE_PEERID_MASK, peer_id);
+}
+
#endif /* _NET_OVPN_OVPNPROTO_H_ */
diff --git a/drivers/net/ovpn/skb.h b/drivers/net/ovpn/skb.h
index 9db7a9adebdb4cc493f162f89fb2e9c6301fa213..bd3cbcfc770d2c28d234fcdd081b4d02e6496ea0 100644
--- a/drivers/net/ovpn/skb.h
+++ b/drivers/net/ovpn/skb.h
@@ -20,6 +20,11 @@
struct ovpn_cb {
struct ovpn_peer *peer;
+ struct ovpn_crypto_key_slot *ks;
+ struct aead_request *req;
+ struct scatterlist *sg;
+ u8 *iv;
+ unsigned int payload_offset;
};
static inline struct ovpn_cb *ovpn_skb_cb(struct sk_buff *skb)
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* Re: [PATCH v21 09/24] ovpn: implement packet processing
2025-03-04 0:33 ` [PATCH v21 09/24] ovpn: implement packet processing Antonio Quartulli
@ 2025-03-04 19:02 ` Sabrina Dubroca
2025-03-04 23:35 ` Antonio Quartulli
0 siblings, 1 reply; 46+ messages in thread
From: Sabrina Dubroca @ 2025-03-04 19:02 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
2025-03-04, 01:33:39 +0100, Antonio Quartulli wrote:
> +struct crypto_aead *ovpn_aead_init(const char *title, const char *alg_name,
> + const unsigned char *key,
> + unsigned int keylen)
nit: static? I don't see it used outside this file.
[...]
> +static inline struct ovpn_crypto_key_slot *
> +ovpn_crypto_key_id_to_slot(const struct ovpn_crypto_state *cs, u8 key_id)
> +{
> + struct ovpn_crypto_key_slot *ks;
> + u8 idx;
> +
> + if (unlikely(!cs))
> + return NULL;
> +
> + rcu_read_lock();
> + idx = cs->primary_idx;
I'd go with slots[0] and slots[1], since it doesn't really matter
whether we check the primary or secondary first. It would avoid a
possible reload of cs->primary_idx (which might be updated
concurrently by a key swap and cause us to look into the same slot
twice) -- a READ_ONCE would also prevent that.
> + ks = rcu_dereference(cs->slots[idx]);
> + if (ks && ks->key_id == key_id) {
> + if (unlikely(!ovpn_crypto_key_slot_hold(ks)))
> + ks = NULL;
> + goto out;
> + }
> +
> + ks = rcu_dereference(cs->slots[!idx]);
> + if (ks && ks->key_id == key_id) {
> + if (unlikely(!ovpn_crypto_key_slot_hold(ks)))
> + ks = NULL;
> + goto out;
> + }
> +
> + /* when both key slots are occupied but no matching key ID is found, ks
> + * has to be reset to NULL to avoid carrying a stale pointer
> + */
> + ks = NULL;
> +out:
> + rcu_read_unlock();
> +
> + return ks;
> +}
--
Sabrina
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 09/24] ovpn: implement packet processing
2025-03-04 19:02 ` Sabrina Dubroca
@ 2025-03-04 23:35 ` Antonio Quartulli
2025-03-05 10:06 ` Sabrina Dubroca
0 siblings, 1 reply; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 23:35 UTC (permalink / raw)
To: Sabrina Dubroca
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
On 04/03/2025 20:02, Sabrina Dubroca wrote:
> 2025-03-04, 01:33:39 +0100, Antonio Quartulli wrote:
>> +struct crypto_aead *ovpn_aead_init(const char *title, const char *alg_name,
>> + const unsigned char *key,
>> + unsigned int keylen)
>
> nit: static? I don't see it used outside this file.
ACK.
>
>
> [...]
>> +static inline struct ovpn_crypto_key_slot *
>> +ovpn_crypto_key_id_to_slot(const struct ovpn_crypto_state *cs, u8 key_id)
>> +{
>> + struct ovpn_crypto_key_slot *ks;
>> + u8 idx;
>> +
>> + if (unlikely(!cs))
>> + return NULL;
>> +
>> + rcu_read_lock();
>> + idx = cs->primary_idx;
>
> I'd go with slots[0] and slots[1], since it doesn't really matter
> whether we check the primary or secondary first. It would avoid a
> possible reload of cs->primary_idx (which might be updated
> concurrently by a key swap and cause us to look into the same slot
> twice) -- a READ_ONCE would also prevent that.
Reason for looking into primary first is that we will most likely need
the primary key to decrypt the incoming traffic.
Secondary is used only during a small (if at all) time window where we
moved to a new key, but our peer was still sending traffic encrypted
with the old (secondary) key.
Therefore optimizing for primary-first may make a non-negligible
difference under heavy load.
Code doesn't get more complex due to this logic, therefore I'd keep this
version (with READ_ONCE(cs->primary_idx)), unless there is a strong
argument against it.
Thanks!
>
>> + ks = rcu_dereference(cs->slots[idx]);
>> + if (ks && ks->key_id == key_id) {
>> + if (unlikely(!ovpn_crypto_key_slot_hold(ks)))
>> + ks = NULL;
>> + goto out;
>> + }
>> +
>> + ks = rcu_dereference(cs->slots[!idx]);
>> + if (ks && ks->key_id == key_id) {
>> + if (unlikely(!ovpn_crypto_key_slot_hold(ks)))
>> + ks = NULL;
>> + goto out;
>> + }
>> +
>> + /* when both key slots are occupied but no matching key ID is found, ks
>> + * has to be reset to NULL to avoid carrying a stale pointer
>> + */
>> + ks = NULL;
>> +out:
>> + rcu_read_unlock();
>> +
>> + return ks;
>> +}
>
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 09/24] ovpn: implement packet processing
2025-03-04 23:35 ` Antonio Quartulli
@ 2025-03-05 10:06 ` Sabrina Dubroca
0 siblings, 0 replies; 46+ messages in thread
From: Sabrina Dubroca @ 2025-03-05 10:06 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
2025-03-05, 00:35:09 +0100, Antonio Quartulli wrote:
> On 04/03/2025 20:02, Sabrina Dubroca wrote:
> > 2025-03-04, 01:33:39 +0100, Antonio Quartulli wrote:
> > [...]
> > > +static inline struct ovpn_crypto_key_slot *
> > > +ovpn_crypto_key_id_to_slot(const struct ovpn_crypto_state *cs, u8 key_id)
> > > +{
> > > + struct ovpn_crypto_key_slot *ks;
> > > + u8 idx;
> > > +
> > > + if (unlikely(!cs))
> > > + return NULL;
> > > +
> > > + rcu_read_lock();
> > > + idx = cs->primary_idx;
> >
> > I'd go with slots[0] and slots[1], since it doesn't really matter
> > whether we check the primary or secondary first. It would avoid a
> > possible reload of cs->primary_idx (which might be updated
> > concurrently by a key swap and cause us to look into the same slot
> > twice) -- a READ_ONCE would also prevent that.
>
> Reason for looking into primary first is that we will most likely need the
> primary key to decrypt the incoming traffic.
>
> Secondary is used only during a small (if at all) time window where we moved
> to a new key, but our peer was still sending traffic encrypted with the old
> (secondary) key.
>
> Therefore optimizing for primary-first may make a non-negligible difference
> under heavy load.
>
> Code doesn't get more complex due to this logic, therefore I'd keep this
> version (with READ_ONCE(cs->primary_idx)), unless there is a strong argument
> against it.
Ok, sounds reasonable.
--
Sabrina
^ permalink raw reply [flat|nested] 46+ messages in thread
* [PATCH v21 10/24] ovpn: store tunnel and transport statistics
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (8 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 09/24] ovpn: implement packet processing Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 11/24] ovpn: implement TCP transport Antonio Quartulli
` (13 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
Byte/packet counters for in-tunnel and transport streams
are now initialized and updated as needed.
To be exported via netlink.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/Makefile | 1 +
drivers/net/ovpn/io.c | 12 +++++++++++-
drivers/net/ovpn/peer.c | 2 ++
drivers/net/ovpn/peer.h | 5 +++++
drivers/net/ovpn/stats.c | 21 +++++++++++++++++++++
drivers/net/ovpn/stats.h | 47 +++++++++++++++++++++++++++++++++++++++++++++++
6 files changed, 87 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
index 38c9fdca0e2e8e4af3c369ceb3971b58ab52d77b..04c3345807c5d759daf65cc80a290f784dbf5588 100644
--- a/drivers/net/ovpn/Makefile
+++ b/drivers/net/ovpn/Makefile
@@ -17,4 +17,5 @@ ovpn-y += netlink-gen.o
ovpn-y += peer.o
ovpn-y += pktid.o
ovpn-y += socket.o
+ovpn-y += stats.o
ovpn-y += udp.o
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index d0b410535ac340a53f010d0b2f20430b26bb012d..50dc2e4c03f01b02bdf616473b755b6e1e6b57f7 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -12,6 +12,7 @@
#include <linux/skbuff.h>
#include <net/gro_cells.h>
#include <net/gso.h>
+#include <net/ip.h>
#include "ovpnpriv.h"
#include "peer.h"
@@ -55,9 +56,11 @@ static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb)
/* cause packet to be "received" by the interface */
pkt_len = skb->len;
ret = gro_cells_receive(&peer->ovpn->gro_cells, skb);
- if (likely(ret == NET_RX_SUCCESS))
+ if (likely(ret == NET_RX_SUCCESS)) {
/* update RX stats with the size of decrypted packet */
+ ovpn_peer_stats_increment_rx(&peer->vpn_stats, pkt_len);
dev_sw_netstats_rx_add(peer->ovpn->dev, pkt_len);
+ }
}
void ovpn_decrypt_post(void *data, int ret)
@@ -158,6 +161,8 @@ void ovpn_recv(struct ovpn_peer *peer, struct sk_buff *skb)
struct ovpn_crypto_key_slot *ks;
u8 key_id;
+ ovpn_peer_stats_increment_rx(&peer->link_stats, skb->len);
+
/* get the key slot matching the key ID in the received packet */
key_id = ovpn_key_id_from_skb(skb);
ks = ovpn_crypto_key_id_to_slot(&peer->crypto, key_id);
@@ -181,6 +186,7 @@ void ovpn_encrypt_post(void *data, int ret)
struct sk_buff *skb = data;
struct ovpn_socket *sock;
struct ovpn_peer *peer;
+ unsigned int orig_len;
/* encryption is happening asynchronously. This function will be
* called later by the crypto callback with a proper return value
@@ -206,6 +212,7 @@ void ovpn_encrypt_post(void *data, int ret)
goto err;
skb_mark_not_on_list(skb);
+ orig_len = skb->len;
rcu_read_lock();
sock = rcu_dereference(peer->sock);
@@ -220,6 +227,8 @@ void ovpn_encrypt_post(void *data, int ret)
/* no transport configured yet */
goto err_unlock;
}
+
+ ovpn_peer_stats_increment_tx(&peer->link_stats, orig_len);
/* skb passed down the stack - don't free it */
skb = NULL;
err_unlock:
@@ -341,6 +350,7 @@ netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev)
goto drop;
}
+ ovpn_peer_stats_increment_tx(&peer->vpn_stats, skb->len);
ovpn_send(ovpn, skb_list.next, peer);
return NETDEV_TX_OK;
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 23eaab1b465b8b88a84cf9f1039621923b640b47..0fe5333c6b8104913526dacc4d7d2260b97f62aa 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -61,6 +61,8 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id)
ovpn_crypto_state_init(&peer->crypto);
spin_lock_init(&peer->lock);
kref_init(&peer->refcount);
+ ovpn_peer_stats_init(&peer->vpn_stats);
+ ovpn_peer_stats_init(&peer->link_stats);
ret = dst_cache_init(&peer->dst_cache, GFP_KERNEL);
if (ret < 0) {
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index a9113a969f94d66fa17208d563d0bbd255c23fa9..2453d39ce327c6d174cfb35fe5430865b32c2efe 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -14,6 +14,7 @@
#include "crypto.h"
#include "socket.h"
+#include "stats.h"
/**
* struct ovpn_peer - the main remote peer object
@@ -27,6 +28,8 @@
* @crypto: the crypto configuration (ciphers, keys, etc..)
* @dst_cache: cache for dst_entry used to send to peer
* @bind: remote peer binding
+ * @vpn_stats: per-peer in-VPN TX/RX stats
+ * @link_stats: per-peer link/transport TX/RX stats
* @delete_reason: why peer was deleted (i.e. timeout, transport error, ..)
* @lock: protects binding to peer (bind)
* @refcount: reference counter
@@ -45,6 +48,8 @@ struct ovpn_peer {
struct ovpn_crypto_state crypto;
struct dst_cache dst_cache;
struct ovpn_bind __rcu *bind;
+ struct ovpn_peer_stats vpn_stats;
+ struct ovpn_peer_stats link_stats;
enum ovpn_del_peer_reason delete_reason;
spinlock_t lock; /* protects bind */
struct kref refcount;
diff --git a/drivers/net/ovpn/stats.c b/drivers/net/ovpn/stats.c
new file mode 100644
index 0000000000000000000000000000000000000000..d637143473bb913647c79832fd9eb3ebfd9efb59
--- /dev/null
+++ b/drivers/net/ovpn/stats.c
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/atomic.h>
+
+#include "stats.h"
+
+void ovpn_peer_stats_init(struct ovpn_peer_stats *ps)
+{
+ atomic64_set(&ps->rx.bytes, 0);
+ atomic64_set(&ps->rx.packets, 0);
+
+ atomic64_set(&ps->tx.bytes, 0);
+ atomic64_set(&ps->tx.packets, 0);
+}
diff --git a/drivers/net/ovpn/stats.h b/drivers/net/ovpn/stats.h
new file mode 100644
index 0000000000000000000000000000000000000000..53433d8b6c33160845de2ae1ca38e85cf31950b7
--- /dev/null
+++ b/drivers/net/ovpn/stats.h
@@ -0,0 +1,47 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ * Lev Stipakov <lev@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_OVPNSTATS_H_
+#define _NET_OVPN_OVPNSTATS_H_
+
+/* one stat */
+struct ovpn_peer_stat {
+ atomic64_t bytes;
+ atomic64_t packets;
+};
+
+/* rx and tx stats combined */
+struct ovpn_peer_stats {
+ struct ovpn_peer_stat rx;
+ struct ovpn_peer_stat tx;
+};
+
+void ovpn_peer_stats_init(struct ovpn_peer_stats *ps);
+
+static inline void ovpn_peer_stats_increment(struct ovpn_peer_stat *stat,
+ const unsigned int n)
+{
+ atomic64_add(n, &stat->bytes);
+ atomic64_inc(&stat->packets);
+}
+
+static inline void ovpn_peer_stats_increment_rx(struct ovpn_peer_stats *stats,
+ const unsigned int n)
+{
+ ovpn_peer_stats_increment(&stats->rx, n);
+}
+
+static inline void ovpn_peer_stats_increment_tx(struct ovpn_peer_stats *stats,
+ const unsigned int n)
+{
+ ovpn_peer_stats_increment(&stats->tx, n);
+}
+
+#endif /* _NET_OVPN_OVPNSTATS_H_ */
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 11/24] ovpn: implement TCP transport
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (9 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 10/24] ovpn: store tunnel and transport statistics Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 12/24] skb: implement skb_send_sock_locked_with_flags() Antonio Quartulli
` (12 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang,
David Ahern
With this change ovpn is allowed to communicate to peers also via TCP.
Parsing of incoming messages is implemented through the strparser API.
Note that ovpn redefines sk_prot and sk_socket->ops for the TCP socket
used to communicate with the peer.
For this reason it needs to access inet6_stream_ops, which is declared
as extern in the IPv6 module, but it is not fully exported.
Therefore this patch is also adding EXPORT_SYMBOL_GPL(inet6_stream_ops)
to net/ipv6/af_inet6.c.
Moreover export tcp_release_cb by means of EXPORT_SYMBOL instead of
EXPORT_IPV6_MOD, so that other modules can use it, even if IPV6 is
not compiled in.
Cc: David Ahern <dsahern@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <horms@kernel.org>
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/Kconfig | 1 +
drivers/net/ovpn/Makefile | 1 +
drivers/net/ovpn/io.c | 4 +
drivers/net/ovpn/main.c | 3 +
drivers/net/ovpn/ovpnpriv.h | 1 +
drivers/net/ovpn/peer.h | 35 +++
drivers/net/ovpn/socket.c | 44 +++-
drivers/net/ovpn/socket.h | 8 +-
drivers/net/ovpn/tcp.c | 588 ++++++++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/tcp.h | 36 +++
net/ipv6/af_inet6.c | 1 +
11 files changed, 711 insertions(+), 11 deletions(-)
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 51d77f3c0848c3c9425b586c6a90cff99a744390..754476cf6dc4774310205dd34f1124795fd2c4f7 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -125,6 +125,7 @@ config OVPN
select CRYPTO_AES
select CRYPTO_GCM
select CRYPTO_CHACHA20POLY1305
+ select STREAM_PARSER
help
This module enhances the performance of the OpenVPN userspace software
by offloading the data channel processing to kernelspace.
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
index 04c3345807c5d759daf65cc80a290f784dbf5588..229be66167e1fe8e5e4c8f475343b544d7ee694e 100644
--- a/drivers/net/ovpn/Makefile
+++ b/drivers/net/ovpn/Makefile
@@ -18,4 +18,5 @@ ovpn-y += peer.o
ovpn-y += pktid.o
ovpn-y += socket.o
ovpn-y += stats.o
+ovpn-y += tcp.o
ovpn-y += udp.o
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index 50dc2e4c03f01b02bdf616473b755b6e1e6b57f7..729f49ff6ce8001c2bbe804db0a617a2cc8965a8 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -22,6 +22,7 @@
#include "crypto_aead.h"
#include "netlink.h"
#include "proto.h"
+#include "tcp.h"
#include "udp.h"
#include "skb.h"
#include "socket.h"
@@ -223,6 +224,9 @@ void ovpn_encrypt_post(void *data, int ret)
case IPPROTO_UDP:
ovpn_udp_send_skb(peer, sock->sock, skb);
break;
+ case IPPROTO_TCP:
+ ovpn_tcp_send_skb(peer, sock->sock, skb);
+ break;
default:
/* no transport configured yet */
goto err_unlock;
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index 82f675f7a49ab9c35ff9686136b949a870b61c06..89b03f45dbc79c5de1f3c62ac9ef229acdc98d3e 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -22,6 +22,7 @@
#include "io.h"
#include "peer.h"
#include "proto.h"
+#include "tcp.h"
#include "udp.h"
static int ovpn_net_init(struct net_device *dev)
@@ -238,6 +239,8 @@ static int __init ovpn_init(void)
goto unreg_rtnl;
}
+ ovpn_tcp_init();
+
return 0;
unreg_rtnl:
diff --git a/drivers/net/ovpn/ovpnpriv.h b/drivers/net/ovpn/ovpnpriv.h
index 9d0640e9c71e7fd494e3d9df155732bd5d82463e..2e3f4baf305f0b37b474d7b7d94751aa4af8a2ea 100644
--- a/drivers/net/ovpn/ovpnpriv.h
+++ b/drivers/net/ovpn/ovpnpriv.h
@@ -10,6 +10,7 @@
#ifndef _NET_OVPN_OVPNSTRUCT_H_
#define _NET_OVPN_OVPNSTRUCT_H_
+#include <linux/workqueue.h>
#include <net/gro_cells.h>
#include <uapi/linux/if_link.h>
#include <uapi/linux/ovpn.h>
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index 2453d39ce327c6d174cfb35fe5430865b32c2efe..5ef00ba6523d7bf6608adb86fa7c7029f559ce2a 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -11,6 +11,7 @@
#define _NET_OVPN_OVPNPEER_H_
#include <net/dst_cache.h>
+#include <net/strparser.h>
#include "crypto.h"
#include "socket.h"
@@ -25,6 +26,18 @@
* @vpn_addrs.ipv4: IPv4 assigned to peer on the tunnel
* @vpn_addrs.ipv6: IPv6 assigned to peer on the tunnel
* @sock: the socket being used to talk to this peer
+ * @tcp: keeps track of TCP specific state
+ * @tcp.strp: stream parser context (TCP only)
+ * @tcp.user_queue: received packets that have to go to userspace (TCP only)
+ * @tcp.out_queue: packets on hold while socket is taken by user (TCP only)
+ * @tcp.tx_in_progress: true if TX is already ongoing (TCP only)
+ * @tcp.out_msg.skb: packet scheduled for sending (TCP only)
+ * @tcp.out_msg.offset: offset where next send should start (TCP only)
+ * @tcp.out_msg.len: remaining data to send within packet (TCP only)
+ * @tcp.sk_cb.sk_data_ready: pointer to original cb (TCP only)
+ * @tcp.sk_cb.sk_write_space: pointer to original cb (TCP only)
+ * @tcp.sk_cb.prot: pointer to original prot object (TCP only)
+ * @tcp.sk_cb.ops: pointer to the original prot_ops object (TCP only)
* @crypto: the crypto configuration (ciphers, keys, etc..)
* @dst_cache: cache for dst_entry used to send to peer
* @bind: remote peer binding
@@ -45,6 +58,28 @@ struct ovpn_peer {
struct in6_addr ipv6;
} vpn_addrs;
struct ovpn_socket __rcu *sock;
+
+ struct {
+ struct strparser strp;
+ struct sk_buff_head user_queue;
+ struct sk_buff_head out_queue;
+ bool tx_in_progress;
+
+ struct {
+ struct sk_buff *skb;
+ int offset;
+ int len;
+ } out_msg;
+
+ struct {
+ void (*sk_data_ready)(struct sock *sk);
+ void (*sk_write_space)(struct sock *sk);
+ struct proto *prot;
+ const struct proto_ops *ops;
+ } sk_cb;
+
+ struct work_struct defer_del_work;
+ } tcp;
struct ovpn_crypto_state crypto;
struct dst_cache dst_cache;
struct ovpn_bind __rcu *bind;
diff --git a/drivers/net/ovpn/socket.c b/drivers/net/ovpn/socket.c
index 6de1e8c85a3d35a5d4f179d595d2409aa34cdc01..be20c500f373fb894d0df5e02ce1996cf386d195 100644
--- a/drivers/net/ovpn/socket.c
+++ b/drivers/net/ovpn/socket.c
@@ -16,6 +16,7 @@
#include "io.h"
#include "peer.h"
#include "socket.h"
+#include "tcp.h"
#include "udp.h"
static void ovpn_socket_release_kref(struct kref *kref)
@@ -23,12 +24,10 @@ static void ovpn_socket_release_kref(struct kref *kref)
struct ovpn_socket *sock = container_of(kref, struct ovpn_socket,
refcount);
- if (sock->sock->sk->sk_protocol == IPPROTO_UDP) {
+ if (sock->sock->sk->sk_protocol == IPPROTO_UDP)
ovpn_udp_socket_detach(sock);
- netdev_put(sock->ovpn->dev, &sock->dev_tracker);
- }
-
- kfree_rcu(sock, rcu);
+ else if (sock->sock->sk->sk_protocol == IPPROTO_TCP)
+ ovpn_tcp_socket_detach(sock);
}
/**
@@ -38,10 +37,12 @@ static void ovpn_socket_release_kref(struct kref *kref)
*
* This function is only used internally. Users willing to release
* references to the ovpn_socket should use ovpn_socket_release()
+ *
+ * Return: true if the socket was released, false otherwise
*/
-static void ovpn_socket_put(struct ovpn_peer *peer, struct ovpn_socket *sock)
+static bool ovpn_socket_put(struct ovpn_peer *peer, struct ovpn_socket *sock)
{
- kref_put(&sock->refcount, ovpn_socket_release_kref);
+ return kref_put(&sock->refcount, ovpn_socket_release_kref);
}
/**
@@ -65,6 +66,7 @@ static void ovpn_socket_put(struct ovpn_peer *peer, struct ovpn_socket *sock)
void ovpn_socket_release(struct ovpn_peer *peer)
{
struct ovpn_socket *sock;
+ bool released;
might_sleep();
@@ -94,11 +96,26 @@ void ovpn_socket_release(struct ovpn_peer *peer)
* detached before it can be picked by a concurrent reader.
*/
lock_sock(sock->sock->sk);
- ovpn_socket_put(peer, sock);
+ released = ovpn_socket_put(peer, sock);
release_sock(sock->sock->sk);
/* align all readers with sk_user_data being NULL */
synchronize_rcu();
+
+ /* following cleanup should happen with lock released */
+ if (released) {
+ if (sock->sock->sk->sk_protocol == IPPROTO_UDP) {
+ netdev_put(sock->ovpn->dev, &sock->dev_tracker);
+ } else if (sock->sock->sk->sk_protocol == IPPROTO_TCP) {
+ /* wait for TCP jobs to terminate */
+ ovpn_tcp_socket_wait_finish(sock);
+ ovpn_peer_put(sock->peer);
+ }
+ /* we can call plain kfree() because we already waited one RCU
+ * period due to synchronize_rcu()
+ */
+ kfree(sock);
+ }
}
static bool ovpn_socket_hold(struct ovpn_socket *sock)
@@ -110,6 +127,8 @@ static int ovpn_socket_attach(struct ovpn_socket *sock, struct ovpn_peer *peer)
{
if (sock->sock->sk->sk_protocol == IPPROTO_UDP)
return ovpn_udp_socket_attach(sock, peer->ovpn);
+ else if (sock->sock->sk->sk_protocol == IPPROTO_TCP)
+ return ovpn_tcp_socket_attach(sock, peer);
return -EOPNOTSUPP;
}
@@ -202,7 +221,14 @@ struct ovpn_socket *ovpn_socket_new(struct socket *sock, struct ovpn_peer *peer)
goto sock_release;
}
- if (sock->sk->sk_protocol == IPPROTO_UDP) {
+ /* TCP sockets are per-peer, therefore they are linked to their unique
+ * peer
+ */
+ if (sock->sk->sk_protocol == IPPROTO_TCP) {
+ INIT_WORK(&ovpn_sock->tcp_tx_work, ovpn_tcp_tx_work);
+ ovpn_sock->peer = peer;
+ ovpn_peer_hold(peer);
+ } else if (sock->sk->sk_protocol == IPPROTO_UDP) {
/* in UDP we only link the ovpn instance since the socket is
* shared among multiple peers
*/
diff --git a/drivers/net/ovpn/socket.h b/drivers/net/ovpn/socket.h
index c1697f4616d470f143cba77bb1db34de0398a37a..00d856b1a5d884ffeca7cde7f693cad599746c10 100644
--- a/drivers/net/ovpn/socket.h
+++ b/drivers/net/ovpn/socket.h
@@ -21,9 +21,11 @@ struct ovpn_peer;
* struct ovpn_socket - a kernel socket referenced in the ovpn code
* @ovpn: ovpn instance owning this socket (UDP only)
* @dev_tracker: reference tracker for associated dev (UDP only)
+ * @peer: unique peer transmitting over this socket (TCP only)
* @sock: the low level sock object
* @refcount: amount of contexts currently referencing this object
- * @rcu: member used to schedule RCU destructor callback
+ * @work: member used to schedule release routine (it may block)
+ * @tcp_tx_work: work for deferring outgoing packet processing (TCP only)
*/
struct ovpn_socket {
union {
@@ -31,11 +33,13 @@ struct ovpn_socket {
struct ovpn_priv *ovpn;
netdevice_tracker dev_tracker;
};
+ struct ovpn_peer *peer;
};
struct socket *sock;
struct kref refcount;
- struct rcu_head rcu;
+ struct work_struct work;
+ struct work_struct tcp_tx_work;
};
struct ovpn_socket *ovpn_socket_new(struct socket *sock,
diff --git a/drivers/net/ovpn/tcp.c b/drivers/net/ovpn/tcp.c
new file mode 100644
index 0000000000000000000000000000000000000000..a5bfd06bc9499b6886b42e039095bb8ce93994fb
--- /dev/null
+++ b/drivers/net/ovpn/tcp.c
@@ -0,0 +1,588 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2025 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/skbuff.h>
+#include <net/hotdata.h>
+#include <net/inet_common.h>
+#include <net/ipv6.h>
+#include <net/tcp.h>
+#include <net/transp_v6.h>
+#include <net/route.h>
+#include <trace/events/sock.h>
+
+#include "ovpnpriv.h"
+#include "main.h"
+#include "io.h"
+#include "peer.h"
+#include "proto.h"
+#include "skb.h"
+#include "tcp.h"
+
+#define OVPN_TCP_DEPTH_NESTING 2
+#if OVPN_TCP_DEPTH_NESTING == SINGLE_DEPTH_NESTING
+#error "OVPN TCP requires its own lockdep subclass"
+#endif
+
+static struct proto ovpn_tcp_prot __ro_after_init;
+static struct proto_ops ovpn_tcp_ops __ro_after_init;
+static struct proto ovpn_tcp6_prot __ro_after_init;
+static struct proto_ops ovpn_tcp6_ops __ro_after_init;
+
+static int ovpn_tcp_parse(struct strparser *strp, struct sk_buff *skb)
+{
+ struct strp_msg *rxm = strp_msg(skb);
+ __be16 blen;
+ u16 len;
+ int err;
+
+ /* when packets are written to the TCP stream, they are prepended with
+ * two bytes indicating the actual packet size.
+ * Parse accordingly and return the actual size (including the size
+ * header)
+ */
+
+ if (skb->len < rxm->offset + 2)
+ return 0;
+
+ err = skb_copy_bits(skb, rxm->offset, &blen, sizeof(blen));
+ if (err < 0)
+ return err;
+
+ len = be16_to_cpu(blen);
+ if (len < 2)
+ return -EINVAL;
+
+ return len + 2;
+}
+
+/* queue skb for sending to userspace via recvmsg on the socket */
+static void ovpn_tcp_to_userspace(struct ovpn_peer *peer, struct sock *sk,
+ struct sk_buff *skb)
+{
+ skb_set_owner_r(skb, sk);
+ memset(skb->cb, 0, sizeof(skb->cb));
+ skb_queue_tail(&peer->tcp.user_queue, skb);
+ peer->tcp.sk_cb.sk_data_ready(sk);
+}
+
+static void ovpn_tcp_rcv(struct strparser *strp, struct sk_buff *skb)
+{
+ struct ovpn_peer *peer = container_of(strp, struct ovpn_peer, tcp.strp);
+ struct strp_msg *msg = strp_msg(skb);
+ size_t pkt_len = msg->full_len - 2;
+ size_t off = msg->offset + 2;
+ u8 opcode;
+
+ /* ensure skb->data points to the beginning of the openvpn packet */
+ if (!pskb_pull(skb, off)) {
+ net_warn_ratelimited("%s: packet too small for peer %u\n",
+ netdev_name(peer->ovpn->dev), peer->id);
+ goto err;
+ }
+
+ /* strparser does not trim the skb for us, therefore we do it now */
+ if (pskb_trim(skb, pkt_len) != 0) {
+ net_warn_ratelimited("%s: trimming skb failed for peer %u\n",
+ netdev_name(peer->ovpn->dev), peer->id);
+ goto err;
+ }
+
+ /* we need the first byte of data to be accessible
+ * to extract the opcode and the key ID later on
+ */
+ if (!pskb_may_pull(skb, OVPN_OPCODE_SIZE)) {
+ net_warn_ratelimited("%s: packet too small to fetch opcode for peer %u\n",
+ netdev_name(peer->ovpn->dev), peer->id);
+ goto err;
+ }
+
+ /* DATA_V2 packets are handled in kernel, the rest goes to user space */
+ opcode = ovpn_opcode_from_skb(skb, 0);
+ if (unlikely(opcode != OVPN_DATA_V2)) {
+ if (opcode == OVPN_DATA_V1) {
+ net_warn_ratelimited("%s: DATA_V1 detected on the TCP stream\n",
+ netdev_name(peer->ovpn->dev));
+ goto err;
+ }
+
+ /* The packet size header must be there when sending the packet
+ * to userspace, therefore we put it back
+ */
+ skb_push(skb, 2);
+ ovpn_tcp_to_userspace(peer, strp->sk, skb);
+ return;
+ }
+
+ /* hold reference to peer as required by ovpn_recv().
+ *
+ * NOTE: in this context we should already be holding a reference to
+ * this peer, therefore ovpn_peer_hold() is not expected to fail
+ */
+ if (WARN_ON(!ovpn_peer_hold(peer)))
+ goto err;
+
+ ovpn_recv(peer, skb);
+ return;
+err:
+ dev_core_stats_rx_dropped_inc(peer->ovpn->dev);
+ kfree_skb(skb);
+ ovpn_peer_del(peer, OVPN_DEL_PEER_REASON_TRANSPORT_ERROR);
+}
+
+static int ovpn_tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
+ int flags, int *addr_len)
+{
+ int err = 0, off, copied = 0, ret;
+ struct ovpn_socket *sock;
+ struct ovpn_peer *peer;
+ struct sk_buff *skb;
+
+ rcu_read_lock();
+ sock = rcu_dereference_sk_user_data(sk);
+ if (unlikely(!sock || !sock->peer || !ovpn_peer_hold(sock->peer))) {
+ rcu_read_unlock();
+ return -EBADF;
+ }
+ peer = sock->peer;
+ rcu_read_unlock();
+
+ skb = __skb_recv_datagram(sk, &peer->tcp.user_queue, flags, &off, &err);
+ if (!skb) {
+ if (err == -EAGAIN && sk->sk_shutdown & RCV_SHUTDOWN) {
+ ret = 0;
+ goto out;
+ }
+ ret = err;
+ goto out;
+ }
+
+ copied = len;
+ if (copied > skb->len)
+ copied = skb->len;
+ else if (copied < skb->len)
+ msg->msg_flags |= MSG_TRUNC;
+
+ err = skb_copy_datagram_msg(skb, 0, msg, copied);
+ if (unlikely(err)) {
+ kfree_skb(skb);
+ ret = err;
+ goto out;
+ }
+
+ if (flags & MSG_TRUNC)
+ copied = skb->len;
+ kfree_skb(skb);
+ ret = copied;
+out:
+ ovpn_peer_put(peer);
+ return ret;
+}
+
+void ovpn_tcp_socket_detach(struct ovpn_socket *ovpn_sock)
+{
+ struct ovpn_peer *peer = ovpn_sock->peer;
+ struct socket *sock = ovpn_sock->sock;
+
+ strp_stop(&peer->tcp.strp);
+ skb_queue_purge(&peer->tcp.user_queue);
+
+ /* restore CBs that were saved in ovpn_sock_set_tcp_cb() */
+ sock->sk->sk_data_ready = peer->tcp.sk_cb.sk_data_ready;
+ sock->sk->sk_write_space = peer->tcp.sk_cb.sk_write_space;
+ sock->sk->sk_prot = peer->tcp.sk_cb.prot;
+ sock->sk->sk_socket->ops = peer->tcp.sk_cb.ops;
+
+ rcu_assign_sk_user_data(sock->sk, NULL);
+}
+
+void ovpn_tcp_socket_wait_finish(struct ovpn_socket *sock)
+{
+ struct ovpn_peer *peer = sock->peer;
+
+ /* NOTE: we don't wait for peer->tcp.defer_del_work to finish:
+ * either the worker is not running or this function
+ * was invoked by that worker.
+ */
+
+ cancel_work_sync(&sock->tcp_tx_work);
+ strp_done(&peer->tcp.strp);
+
+ skb_queue_purge(&peer->tcp.out_queue);
+ kfree_skb(peer->tcp.out_msg.skb);
+ peer->tcp.out_msg.skb = NULL;
+}
+
+static void ovpn_tcp_send_sock(struct ovpn_peer *peer, struct sock *sk)
+{
+ struct sk_buff *skb = peer->tcp.out_msg.skb;
+
+ if (!skb)
+ return;
+
+ if (peer->tcp.tx_in_progress)
+ return;
+
+ peer->tcp.tx_in_progress = true;
+
+ do {
+ int ret = skb_send_sock_locked(sk, skb,
+ peer->tcp.out_msg.offset,
+ peer->tcp.out_msg.len);
+ if (unlikely(ret < 0)) {
+ if (ret == -EAGAIN)
+ goto out;
+
+ net_warn_ratelimited("%s: TCP error to peer %u: %d\n",
+ netdev_name(peer->ovpn->dev),
+ peer->id, ret);
+
+ /* in case of TCP error we can't recover the VPN
+ * stream therefore we abort the connection
+ */
+ ovpn_peer_hold(peer);
+ schedule_work(&peer->tcp.defer_del_work);
+
+ /* we bail out immediately and keep tx_in_progress set
+ * to true. This way we prevent more TX attempts
+ * which would lead to more invocations of
+ * schedule_work()
+ */
+ return;
+ }
+
+ peer->tcp.out_msg.len -= ret;
+ peer->tcp.out_msg.offset += ret;
+ } while (peer->tcp.out_msg.len > 0);
+
+ if (!peer->tcp.out_msg.len) {
+ preempt_disable();
+ dev_sw_netstats_tx_add(peer->ovpn->dev, 1, skb->len);
+ preempt_enable();
+ }
+
+ kfree_skb(peer->tcp.out_msg.skb);
+ peer->tcp.out_msg.skb = NULL;
+ peer->tcp.out_msg.len = 0;
+ peer->tcp.out_msg.offset = 0;
+
+out:
+ peer->tcp.tx_in_progress = false;
+}
+
+void ovpn_tcp_tx_work(struct work_struct *work)
+{
+ struct ovpn_socket *sock;
+
+ sock = container_of(work, struct ovpn_socket, tcp_tx_work);
+
+ lock_sock(sock->sock->sk);
+ if (sock->peer)
+ ovpn_tcp_send_sock(sock->peer, sock->sock->sk);
+ release_sock(sock->sock->sk);
+}
+
+static void ovpn_tcp_send_sock_skb(struct ovpn_peer *peer, struct sock *sk,
+ struct sk_buff *skb)
+{
+ if (peer->tcp.out_msg.skb)
+ ovpn_tcp_send_sock(peer, sk);
+
+ if (peer->tcp.out_msg.skb) {
+ dev_core_stats_tx_dropped_inc(peer->ovpn->dev);
+ kfree_skb(skb);
+ return;
+ }
+
+ peer->tcp.out_msg.skb = skb;
+ peer->tcp.out_msg.len = skb->len;
+ peer->tcp.out_msg.offset = 0;
+ ovpn_tcp_send_sock(peer, sk);
+}
+
+void ovpn_tcp_send_skb(struct ovpn_peer *peer, struct socket *sock,
+ struct sk_buff *skb)
+{
+ u16 len = skb->len;
+
+ *(__be16 *)__skb_push(skb, sizeof(u16)) = htons(len);
+
+ spin_lock_nested(&sock->sk->sk_lock.slock, OVPN_TCP_DEPTH_NESTING);
+ if (sock_owned_by_user(sock->sk)) {
+ if (skb_queue_len(&peer->tcp.out_queue) >=
+ READ_ONCE(net_hotdata.max_backlog)) {
+ dev_core_stats_tx_dropped_inc(peer->ovpn->dev);
+ kfree_skb(skb);
+ goto unlock;
+ }
+ __skb_queue_tail(&peer->tcp.out_queue, skb);
+ } else {
+ ovpn_tcp_send_sock_skb(peer, sock->sk, skb);
+ }
+unlock:
+ spin_unlock(&sock->sk->sk_lock.slock);
+}
+
+static void ovpn_tcp_release(struct sock *sk)
+{
+ struct sk_buff_head queue;
+ struct ovpn_socket *sock;
+ struct ovpn_peer *peer;
+ struct sk_buff *skb;
+
+ rcu_read_lock();
+ sock = rcu_dereference_sk_user_data(sk);
+ if (!sock) {
+ rcu_read_unlock();
+ return;
+ }
+
+ peer = sock->peer;
+
+ /* during initialization this function is called before
+ * assigning sock->peer
+ */
+ if (unlikely(!peer || !ovpn_peer_hold(peer))) {
+ rcu_read_unlock();
+ return;
+ }
+ rcu_read_unlock();
+
+ __skb_queue_head_init(&queue);
+ skb_queue_splice_init(&peer->tcp.out_queue, &queue);
+
+ while ((skb = __skb_dequeue(&queue)))
+ ovpn_tcp_send_sock_skb(peer, sk, skb);
+
+ peer->tcp.sk_cb.prot->release_cb(sk);
+ ovpn_peer_put(peer);
+}
+
+static int ovpn_tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
+{
+ struct ovpn_socket *sock;
+ int ret, linear = PAGE_SIZE;
+ struct ovpn_peer *peer;
+ struct sk_buff *skb;
+
+ lock_sock(sk);
+ rcu_read_lock();
+ sock = rcu_dereference_sk_user_data(sk);
+ if (unlikely(!sock || !sock->peer || !ovpn_peer_hold(sock->peer))) {
+ rcu_read_unlock();
+ release_sock(sk);
+ return -EIO;
+ }
+ rcu_read_unlock();
+ peer = sock->peer;
+
+ if (msg->msg_flags & ~MSG_DONTWAIT) {
+ ret = -EOPNOTSUPP;
+ goto peer_free;
+ }
+
+ if (peer->tcp.out_msg.skb) {
+ ret = -EAGAIN;
+ goto peer_free;
+ }
+
+ if (size < linear)
+ linear = size;
+
+ skb = sock_alloc_send_pskb(sk, linear, size - linear,
+ msg->msg_flags & MSG_DONTWAIT, &ret, 0);
+ if (!skb) {
+ net_err_ratelimited("%s: skb alloc failed: %d\n",
+ netdev_name(peer->ovpn->dev), ret);
+ goto peer_free;
+ }
+
+ skb_put(skb, linear);
+ skb->len = size;
+ skb->data_len = size - linear;
+
+ ret = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, size);
+ if (ret) {
+ kfree_skb(skb);
+ net_err_ratelimited("%s: skb copy from iter failed: %d\n",
+ netdev_name(peer->ovpn->dev), ret);
+ goto peer_free;
+ }
+
+ ovpn_tcp_send_sock_skb(peer, sk, skb);
+ ret = size;
+peer_free:
+ release_sock(sk);
+ ovpn_peer_put(peer);
+ return ret;
+}
+
+static void ovpn_tcp_data_ready(struct sock *sk)
+{
+ struct ovpn_socket *sock;
+
+ trace_sk_data_ready(sk);
+
+ rcu_read_lock();
+ sock = rcu_dereference_sk_user_data(sk);
+ if (likely(sock && sock->peer))
+ strp_data_ready(&sock->peer->tcp.strp);
+ rcu_read_unlock();
+}
+
+static void ovpn_tcp_write_space(struct sock *sk)
+{
+ struct ovpn_socket *sock;
+
+ rcu_read_lock();
+ sock = rcu_dereference_sk_user_data(sk);
+ if (likely(sock && sock->peer)) {
+ schedule_work(&sock->tcp_tx_work);
+ sock->peer->tcp.sk_cb.sk_write_space(sk);
+ }
+ rcu_read_unlock();
+}
+
+static void ovpn_tcp_build_protos(struct proto *new_prot,
+ struct proto_ops *new_ops,
+ const struct proto *orig_prot,
+ const struct proto_ops *orig_ops);
+
+static void ovpn_tcp_peer_del_work(struct work_struct *work)
+{
+ struct ovpn_peer *peer = container_of(work, struct ovpn_peer,
+ tcp.defer_del_work);
+
+ ovpn_peer_del(peer, OVPN_DEL_PEER_REASON_TRANSPORT_ERROR);
+ ovpn_peer_put(peer);
+}
+
+/* Set TCP encapsulation callbacks */
+int ovpn_tcp_socket_attach(struct ovpn_socket *ovpn_sock,
+ struct ovpn_peer *peer)
+{
+ struct socket *sock = ovpn_sock->sock;
+ struct strp_callbacks cb = {
+ .rcv_msg = ovpn_tcp_rcv,
+ .parse_msg = ovpn_tcp_parse,
+ };
+ int ret;
+
+ /* make sure no pre-existing encapsulation handler exists */
+ if (sock->sk->sk_user_data)
+ return -EBUSY;
+
+ /* only a fully connected socket is expected. Connection should be
+ * handled in userspace
+ */
+ if (sock->sk->sk_state != TCP_ESTABLISHED) {
+ net_err_ratelimited("%s: provided TCP socket is not in ESTABLISHED state: %d\n",
+ netdev_name(peer->ovpn->dev),
+ sock->sk->sk_state);
+ return -EINVAL;
+ }
+
+ ret = strp_init(&peer->tcp.strp, sock->sk, &cb);
+ if (ret < 0) {
+ DEBUG_NET_WARN_ON_ONCE(1);
+ return ret;
+ }
+
+ INIT_WORK(&peer->tcp.defer_del_work, ovpn_tcp_peer_del_work);
+
+ __sk_dst_reset(sock->sk);
+ skb_queue_head_init(&peer->tcp.user_queue);
+ skb_queue_head_init(&peer->tcp.out_queue);
+
+ /* save current CBs so that they can be restored upon socket release */
+ peer->tcp.sk_cb.sk_data_ready = sock->sk->sk_data_ready;
+ peer->tcp.sk_cb.sk_write_space = sock->sk->sk_write_space;
+ peer->tcp.sk_cb.prot = sock->sk->sk_prot;
+ peer->tcp.sk_cb.ops = sock->sk->sk_socket->ops;
+
+ /* assign our static CBs and prot/ops */
+ sock->sk->sk_data_ready = ovpn_tcp_data_ready;
+ sock->sk->sk_write_space = ovpn_tcp_write_space;
+
+ if (sock->sk->sk_family == AF_INET) {
+ sock->sk->sk_prot = &ovpn_tcp_prot;
+ sock->sk->sk_socket->ops = &ovpn_tcp_ops;
+ } else {
+ sock->sk->sk_prot = &ovpn_tcp6_prot;
+ sock->sk->sk_socket->ops = &ovpn_tcp6_ops;
+ }
+
+ /* avoid using task_frag */
+ sock->sk->sk_allocation = GFP_ATOMIC;
+ sock->sk->sk_use_task_frag = false;
+
+ /* enqueue the RX worker */
+ strp_check_rcv(&peer->tcp.strp);
+
+ return 0;
+}
+
+static void ovpn_tcp_close(struct sock *sk, long timeout)
+{
+ struct ovpn_socket *sock;
+ struct ovpn_peer *peer;
+
+ rcu_read_lock();
+ sock = rcu_dereference_sk_user_data(sk);
+ if (!sock || !sock->peer || !ovpn_peer_hold(sock->peer)) {
+ rcu_read_unlock();
+ return;
+ }
+ peer = sock->peer;
+ rcu_read_unlock();
+
+ ovpn_peer_del(sock->peer, OVPN_DEL_PEER_REASON_TRANSPORT_DISCONNECT);
+ peer->tcp.sk_cb.prot->close(sk, timeout);
+ ovpn_peer_put(peer);
+}
+
+static __poll_t ovpn_tcp_poll(struct file *file, struct socket *sock,
+ poll_table *wait)
+{
+ __poll_t mask = datagram_poll(file, sock, wait);
+ struct ovpn_socket *ovpn_sock;
+
+ rcu_read_lock();
+ ovpn_sock = rcu_dereference_sk_user_data(sock->sk);
+ if (ovpn_sock && ovpn_sock->peer &&
+ !skb_queue_empty(&ovpn_sock->peer->tcp.user_queue))
+ mask |= EPOLLIN | EPOLLRDNORM;
+ rcu_read_unlock();
+
+ return mask;
+}
+
+static void ovpn_tcp_build_protos(struct proto *new_prot,
+ struct proto_ops *new_ops,
+ const struct proto *orig_prot,
+ const struct proto_ops *orig_ops)
+{
+ memcpy(new_prot, orig_prot, sizeof(*new_prot));
+ memcpy(new_ops, orig_ops, sizeof(*new_ops));
+ new_prot->recvmsg = ovpn_tcp_recvmsg;
+ new_prot->sendmsg = ovpn_tcp_sendmsg;
+ new_prot->close = ovpn_tcp_close;
+ new_prot->release_cb = ovpn_tcp_release;
+ new_ops->poll = ovpn_tcp_poll;
+}
+
+/* Initialize TCP static objects */
+void __init ovpn_tcp_init(void)
+{
+ ovpn_tcp_build_protos(&ovpn_tcp_prot, &ovpn_tcp_ops, &tcp_prot,
+ &inet_stream_ops);
+
+#if IS_ENABLED(CONFIG_IPV6)
+ ovpn_tcp_build_protos(&ovpn_tcp6_prot, &ovpn_tcp6_ops, &tcpv6_prot,
+ &inet6_stream_ops);
+#endif
+}
diff --git a/drivers/net/ovpn/tcp.h b/drivers/net/ovpn/tcp.h
new file mode 100644
index 0000000000000000000000000000000000000000..10aefa834cf358f39f4fc250063d6ef13e0353b0
--- /dev/null
+++ b/drivers/net/ovpn/tcp.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2025 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_TCP_H_
+#define _NET_OVPN_TCP_H_
+
+#include <linux/net.h>
+#include <linux/skbuff.h>
+#include <linux/types.h>
+
+#include "peer.h"
+#include "skb.h"
+#include "socket.h"
+
+void __init ovpn_tcp_init(void);
+
+int ovpn_tcp_socket_attach(struct ovpn_socket *ovpn_sock,
+ struct ovpn_peer *peer);
+void ovpn_tcp_socket_detach(struct ovpn_socket *ovpn_sock);
+void ovpn_tcp_socket_wait_finish(struct ovpn_socket *sock);
+
+/* Prepare skb and enqueue it for sending to peer.
+ *
+ * Preparation consist in prepending the skb payload with its size.
+ * Required by the OpenVPN protocol in order to extract packets from
+ * the TCP stream on the receiver side.
+ */
+void ovpn_tcp_send_skb(struct ovpn_peer *peer, struct socket *sock, struct sk_buff *skb);
+void ovpn_tcp_tx_work(struct work_struct *work);
+
+#endif /* _NET_OVPN_TCP_H_ */
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index f60ec8b0f8ea40b2d635d802a3bc4f9b9d844417..3e812187e125cec7deac88413b85a35dd5b22a2d 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -715,6 +715,7 @@ const struct proto_ops inet6_stream_ops = {
#endif
.set_rcvlowat = tcp_set_rcvlowat,
};
+EXPORT_SYMBOL_GPL(inet6_stream_ops);
const struct proto_ops inet6_dgram_ops = {
.family = PF_INET6,
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 12/24] skb: implement skb_send_sock_locked_with_flags()
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (10 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 11/24] ovpn: implement TCP transport Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 13/24] ovpn: add support for MSG_NOSIGNAL in tcp_sendmsg Antonio Quartulli
` (11 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
When sending an skb over a socket using skb_send_sock_locked(),
it is currently not possible to specify any flag to be set in
msghdr->msg_flags.
However, we may want to pass flags the user may have specified,
like MSG_NOSIGNAL.
Extend __skb_send_sock() with a new argument 'flags' and add a
new interface named skb_send_sock_locked_with_flags().
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <horms@kernel.org>
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
include/linux/skbuff.h | 2 ++
net/core/skbuff.c | 18 +++++++++++++-----
2 files changed, 15 insertions(+), 5 deletions(-)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 14517e95a46c4e6f9a04ef7c7193b82b5e145b28..afd694b856b0dee3a657f23cb92cdd33885efbb1 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -4162,6 +4162,8 @@ int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset,
unsigned int flags);
int skb_send_sock_locked(struct sock *sk, struct sk_buff *skb, int offset,
int len);
+int skb_send_sock_locked_with_flags(struct sock *sk, struct sk_buff *skb,
+ int offset, int len, int flags);
int skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset, int len);
void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to);
unsigned int skb_zerocopy_headlen(const struct sk_buff *from);
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index ab8acb737b93299f503e5c298b87e18edd59d555..bd627cfea8052faf3e9e745291b54ed22d2e7ed3 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3239,7 +3239,7 @@ static int sendmsg_unlocked(struct sock *sk, struct msghdr *msg)
typedef int (*sendmsg_func)(struct sock *sk, struct msghdr *msg);
static int __skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset,
- int len, sendmsg_func sendmsg)
+ int len, sendmsg_func sendmsg, int flags)
{
unsigned int orig_len = len;
struct sk_buff *head = skb;
@@ -3257,7 +3257,7 @@ static int __skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset,
kv.iov_base = skb->data + offset;
kv.iov_len = slen;
memset(&msg, 0, sizeof(msg));
- msg.msg_flags = MSG_DONTWAIT;
+ msg.msg_flags = MSG_DONTWAIT | flags;
iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &kv, 1, slen);
ret = INDIRECT_CALL_2(sendmsg, sendmsg_locked,
@@ -3294,7 +3294,8 @@ static int __skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset,
while (slen) {
struct bio_vec bvec;
struct msghdr msg = {
- .msg_flags = MSG_SPLICE_PAGES | MSG_DONTWAIT,
+ .msg_flags = MSG_SPLICE_PAGES | MSG_DONTWAIT |
+ flags,
};
bvec_set_page(&bvec, skb_frag_page(frag), slen,
@@ -3340,14 +3341,21 @@ static int __skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset,
int skb_send_sock_locked(struct sock *sk, struct sk_buff *skb, int offset,
int len)
{
- return __skb_send_sock(sk, skb, offset, len, sendmsg_locked);
+ return __skb_send_sock(sk, skb, offset, len, sendmsg_locked, 0);
}
EXPORT_SYMBOL_GPL(skb_send_sock_locked);
+int skb_send_sock_locked_with_flags(struct sock *sk, struct sk_buff *skb,
+ int offset, int len, int flags)
+{
+ return __skb_send_sock(sk, skb, offset, len, sendmsg_locked, flags);
+}
+EXPORT_SYMBOL_GPL(skb_send_sock_locked_with_flags);
+
/* Send skb data on a socket. Socket must be unlocked. */
int skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset, int len)
{
- return __skb_send_sock(sk, skb, offset, len, sendmsg_unlocked);
+ return __skb_send_sock(sk, skb, offset, len, sendmsg_unlocked, 0);
}
/**
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 13/24] ovpn: add support for MSG_NOSIGNAL in tcp_sendmsg
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (11 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 12/24] skb: implement skb_send_sock_locked_with_flags() Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 14/24] ovpn: implement multi-peer support Antonio Quartulli
` (10 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
Userspace may want to pass the MSG_NOSIGNAL flag to
tcp_sendmsg() in order to avoid generating a SIGPIPE.
To pass this flag down the TCP stack a new skb sending API
accepting a flags argument is introduced.
Cc: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/skb.h | 1 +
drivers/net/ovpn/tcp.c | 12 ++++++++----
2 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ovpn/skb.h b/drivers/net/ovpn/skb.h
index bd3cbcfc770d2c28d234fcdd081b4d02e6496ea0..64430880f1dae33a41f698d713cf151be5b38577 100644
--- a/drivers/net/ovpn/skb.h
+++ b/drivers/net/ovpn/skb.h
@@ -25,6 +25,7 @@ struct ovpn_cb {
struct scatterlist *sg;
u8 *iv;
unsigned int payload_offset;
+ bool nosignal;
};
static inline struct ovpn_cb *ovpn_skb_cb(struct sk_buff *skb)
diff --git a/drivers/net/ovpn/tcp.c b/drivers/net/ovpn/tcp.c
index a5bfd06bc9499b6886b42e039095bb8ce93994fb..e05c9ba0e0f5f74bd99fc0ed918fb93cd1f3d494 100644
--- a/drivers/net/ovpn/tcp.c
+++ b/drivers/net/ovpn/tcp.c
@@ -220,6 +220,7 @@ void ovpn_tcp_socket_wait_finish(struct ovpn_socket *sock)
static void ovpn_tcp_send_sock(struct ovpn_peer *peer, struct sock *sk)
{
struct sk_buff *skb = peer->tcp.out_msg.skb;
+ int ret, flags;
if (!skb)
return;
@@ -230,9 +231,11 @@ static void ovpn_tcp_send_sock(struct ovpn_peer *peer, struct sock *sk)
peer->tcp.tx_in_progress = true;
do {
- int ret = skb_send_sock_locked(sk, skb,
- peer->tcp.out_msg.offset,
- peer->tcp.out_msg.len);
+ flags = ovpn_skb_cb(skb)->nosignal ? MSG_NOSIGNAL : 0;
+ ret = skb_send_sock_locked_with_flags(sk, skb,
+ peer->tcp.out_msg.offset,
+ peer->tcp.out_msg.len,
+ flags);
if (unlikely(ret < 0)) {
if (ret == -EAGAIN)
goto out;
@@ -380,7 +383,7 @@ static int ovpn_tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
rcu_read_unlock();
peer = sock->peer;
- if (msg->msg_flags & ~MSG_DONTWAIT) {
+ if (msg->msg_flags & ~(MSG_DONTWAIT | MSG_NOSIGNAL)) {
ret = -EOPNOTSUPP;
goto peer_free;
}
@@ -413,6 +416,7 @@ static int ovpn_tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
goto peer_free;
}
+ ovpn_skb_cb(skb)->nosignal = msg->msg_flags & MSG_NOSIGNAL;
ovpn_tcp_send_sock_skb(peer, sk, skb);
ret = size;
peer_free:
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 14/24] ovpn: implement multi-peer support
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (12 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 13/24] ovpn: add support for MSG_NOSIGNAL in tcp_sendmsg Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 15/24] ovpn: implement peer lookup logic Antonio Quartulli
` (9 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
With this change an ovpn instance will be able to stay connected to
multiple remote endpoints.
This functionality is strictly required when running ovpn on an
OpenVPN server.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/main.c | 64 +++++++++++++--
drivers/net/ovpn/ovpnpriv.h | 19 +++++
drivers/net/ovpn/peer.c | 189 ++++++++++++++++++++++++++++++++++++++++++--
drivers/net/ovpn/peer.h | 12 ++-
drivers/net/ovpn/udp.c | 4 +-
5 files changed, 272 insertions(+), 16 deletions(-)
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index 89b03f45dbc79c5de1f3c62ac9ef229acdc98d3e..333a025a69094f1be3fb0a7a934da0cdb5abdcde 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -25,11 +25,66 @@
#include "tcp.h"
#include "udp.h"
+static void ovpn_priv_free(struct net_device *net)
+{
+ struct ovpn_priv *ovpn = netdev_priv(net);
+
+ kfree(ovpn->peers);
+}
+
+static int ovpn_mp_alloc(struct ovpn_priv *ovpn)
+{
+ struct in_device *dev_v4;
+ int i;
+
+ if (ovpn->mode != OVPN_MODE_MP)
+ return 0;
+
+ dev_v4 = __in_dev_get_rtnl(ovpn->dev);
+ if (dev_v4) {
+ /* disable redirects as Linux gets confused by ovpn
+ * handling same-LAN routing.
+ * This happens because a multipeer interface is used as
+ * relay point between hosts in the same subnet, while
+ * in a classic LAN this would not be needed because the
+ * two hosts would be able to talk directly.
+ */
+ IN_DEV_CONF_SET(dev_v4, SEND_REDIRECTS, false);
+ IPV4_DEVCONF_ALL(dev_net(ovpn->dev), SEND_REDIRECTS) = false;
+ }
+
+ /* the peer container is fairly large, therefore we allocate it only in
+ * MP mode
+ */
+ ovpn->peers = kzalloc(sizeof(*ovpn->peers), GFP_KERNEL);
+ if (!ovpn->peers)
+ return -ENOMEM;
+
+ for (i = 0; i < ARRAY_SIZE(ovpn->peers->by_id); i++) {
+ INIT_HLIST_HEAD(&ovpn->peers->by_id[i]);
+ INIT_HLIST_NULLS_HEAD(&ovpn->peers->by_vpn_addr4[i], i);
+ INIT_HLIST_NULLS_HEAD(&ovpn->peers->by_vpn_addr6[i], i);
+ INIT_HLIST_NULLS_HEAD(&ovpn->peers->by_transp_addr[i], i);
+ }
+
+ return 0;
+}
+
static int ovpn_net_init(struct net_device *dev)
{
struct ovpn_priv *ovpn = netdev_priv(dev);
+ int err = gro_cells_init(&ovpn->gro_cells, dev);
- return gro_cells_init(&ovpn->gro_cells, dev);
+ if (err < 0)
+ return err;
+
+ err = ovpn_mp_alloc(ovpn);
+ if (err < 0) {
+ gro_cells_destroy(&ovpn->gro_cells);
+ return err;
+ }
+
+ return 0;
}
static void ovpn_net_uninit(struct net_device *dev)
@@ -100,6 +155,8 @@ static void ovpn_setup(struct net_device *dev)
dev->netdev_ops = &ovpn_netdev_ops;
+ dev->priv_destructor = ovpn_priv_free;
+
dev->hard_header_len = 0;
dev->addr_len = 0;
dev->mtu = ETH_DATA_LEN - OVPN_HEAD_ROOM;
@@ -196,10 +253,7 @@ static int ovpn_netdev_notifier_call(struct notifier_block *nb,
netif_carrier_off(dev);
ovpn->registered = false;
-
- if (ovpn->mode == OVPN_MODE_P2P)
- ovpn_peer_release_p2p(ovpn, NULL,
- OVPN_DEL_PEER_REASON_TEARDOWN);
+ ovpn_peers_free(ovpn, NULL, OVPN_DEL_PEER_REASON_TEARDOWN);
break;
case NETDEV_POST_INIT:
case NETDEV_GOING_DOWN:
diff --git a/drivers/net/ovpn/ovpnpriv.h b/drivers/net/ovpn/ovpnpriv.h
index 2e3f4baf305f0b37b474d7b7d94751aa4af8a2ea..b26ad97215a3d42242ba349b348c2749f570797c 100644
--- a/drivers/net/ovpn/ovpnpriv.h
+++ b/drivers/net/ovpn/ovpnpriv.h
@@ -15,12 +15,30 @@
#include <uapi/linux/if_link.h>
#include <uapi/linux/ovpn.h>
+/**
+ * struct ovpn_peer_collection - container of peers for MultiPeer mode
+ * @by_id: table of peers index by ID
+ * @by_vpn_addr4: table of peers indexed by VPN IPv4 address (items can be
+ * rehashed on the fly due to peer IP change)
+ * @by_vpn_addr6: table of peers indexed by VPN IPv6 address (items can be
+ * rehashed on the fly due to peer IP change)
+ * @by_transp_addr: table of peers indexed by transport address (items can be
+ * rehashed on the fly due to peer IP change)
+ */
+struct ovpn_peer_collection {
+ DECLARE_HASHTABLE(by_id, 12);
+ struct hlist_nulls_head by_vpn_addr4[1 << 12];
+ struct hlist_nulls_head by_vpn_addr6[1 << 12];
+ struct hlist_nulls_head by_transp_addr[1 << 12];
+};
+
/**
* struct ovpn_priv - per ovpn interface state
* @dev: the actual netdev representing the tunnel
* @registered: whether dev is still registered with netdev or not
* @mode: device operation mode (i.e. p2p, mp, ..)
* @lock: protect this object
+ * @peers: data structures holding multi-peer references
* @peer: in P2P mode, this is the only remote peer
* @gro_cells: pointer to the Generic Receive Offload cell
*/
@@ -29,6 +47,7 @@ struct ovpn_priv {
bool registered;
enum ovpn_mode mode;
spinlock_t lock; /* protect writing to the ovpn_priv object */
+ struct ovpn_peer_collection *peers;
struct ovpn_peer __rcu *peer;
struct gro_cells gro_cells;
};
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 0fe5333c6b8104913526dacc4d7d2260b97f62aa..bed2e591c000c4efecdcd92db484e590f97f9f7f 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -9,6 +9,7 @@
#include <linux/skbuff.h>
#include <linux/list.h>
+#include <linux/hashtable.h>
#include "ovpnpriv.h"
#include "bind.h"
@@ -280,7 +281,19 @@ static void ovpn_peer_remove(struct ovpn_peer *peer,
enum ovpn_del_peer_reason reason,
struct llist_head *release_list)
{
+ lockdep_assert_held(&peer->ovpn->lock);
+
switch (peer->ovpn->mode) {
+ case OVPN_MODE_MP:
+ /* prevent double remove */
+ if (hlist_unhashed(&peer->hash_entry_id))
+ return;
+
+ hlist_del_init_rcu(&peer->hash_entry_id);
+ hlist_nulls_del_init_rcu(&peer->hash_entry_addr4);
+ hlist_nulls_del_init_rcu(&peer->hash_entry_addr6);
+ hlist_nulls_del_init_rcu(&peer->hash_entry_transp_addr);
+ break;
case OVPN_MODE_P2P:
/* prevent double remove */
if (peer != rcu_access_pointer(peer->ovpn->peer))
@@ -292,8 +305,6 @@ static void ovpn_peer_remove(struct ovpn_peer *peer,
*/
netif_carrier_off(peer->ovpn->dev);
break;
- default:
- return;
}
peer->delete_reason = reason;
@@ -357,6 +368,89 @@ bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb,
return match;
}
+#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \
+ typeof(_tbl) *__tbl = &(_tbl); \
+ (&(*__tbl)[jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl)]); }) \
+
+/**
+ * ovpn_peer_add_mp - add peer to related tables in a MP instance
+ * @ovpn: the instance to add the peer to
+ * @peer: the peer to add
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+static int ovpn_peer_add_mp(struct ovpn_priv *ovpn, struct ovpn_peer *peer)
+{
+ struct sockaddr_storage sa = { 0 };
+ struct hlist_nulls_head *nhead;
+ struct sockaddr_in6 *sa6;
+ struct sockaddr_in *sa4;
+ struct ovpn_bind *bind;
+ struct ovpn_peer *tmp;
+ size_t salen;
+ int ret = 0;
+
+ spin_lock_bh(&ovpn->lock);
+ /* do not add duplicates */
+ tmp = ovpn_peer_get_by_id(ovpn, peer->id);
+ if (tmp) {
+ ovpn_peer_put(tmp);
+ ret = -EEXIST;
+ goto out;
+ }
+
+ bind = rcu_dereference_protected(peer->bind, true);
+ /* peers connected via TCP have bind == NULL */
+ if (bind) {
+ switch (bind->remote.in4.sin_family) {
+ case AF_INET:
+ sa4 = (struct sockaddr_in *)&sa;
+
+ sa4->sin_family = AF_INET;
+ sa4->sin_addr.s_addr = bind->remote.in4.sin_addr.s_addr;
+ sa4->sin_port = bind->remote.in4.sin_port;
+ salen = sizeof(*sa4);
+ break;
+ case AF_INET6:
+ sa6 = (struct sockaddr_in6 *)&sa;
+
+ sa6->sin6_family = AF_INET6;
+ sa6->sin6_addr = bind->remote.in6.sin6_addr;
+ sa6->sin6_port = bind->remote.in6.sin6_port;
+ salen = sizeof(*sa6);
+ break;
+ default:
+ ret = -EPROTONOSUPPORT;
+ goto out;
+ }
+
+ nhead = ovpn_get_hash_head(ovpn->peers->by_transp_addr, &sa,
+ salen);
+ hlist_nulls_add_head_rcu(&peer->hash_entry_transp_addr, nhead);
+ }
+
+ hlist_add_head_rcu(&peer->hash_entry_id,
+ ovpn_get_hash_head(ovpn->peers->by_id, &peer->id,
+ sizeof(peer->id)));
+
+ if (peer->vpn_addrs.ipv4.s_addr != htonl(INADDR_ANY)) {
+ nhead = ovpn_get_hash_head(ovpn->peers->by_vpn_addr4,
+ &peer->vpn_addrs.ipv4,
+ sizeof(peer->vpn_addrs.ipv4));
+ hlist_nulls_add_head_rcu(&peer->hash_entry_addr4, nhead);
+ }
+
+ if (!ipv6_addr_any(&peer->vpn_addrs.ipv6)) {
+ nhead = ovpn_get_hash_head(ovpn->peers->by_vpn_addr6,
+ &peer->vpn_addrs.ipv6,
+ sizeof(peer->vpn_addrs.ipv6));
+ hlist_nulls_add_head_rcu(&peer->hash_entry_addr6, nhead);
+ }
+out:
+ spin_unlock_bh(&ovpn->lock);
+ return ret;
+}
+
/**
* ovpn_peer_add_p2p - add peer to related tables in a P2P instance
* @ovpn: the instance to add the peer to
@@ -399,11 +493,42 @@ static int ovpn_peer_add_p2p(struct ovpn_priv *ovpn, struct ovpn_peer *peer)
int ovpn_peer_add(struct ovpn_priv *ovpn, struct ovpn_peer *peer)
{
switch (ovpn->mode) {
+ case OVPN_MODE_MP:
+ return ovpn_peer_add_mp(ovpn, peer);
case OVPN_MODE_P2P:
return ovpn_peer_add_p2p(ovpn, peer);
- default:
- return -EOPNOTSUPP;
}
+
+ return -EOPNOTSUPP;
+}
+
+/**
+ * ovpn_peer_del_mp - delete peer from related tables in a MP instance
+ * @peer: the peer to delete
+ * @reason: reason why the peer was deleted (sent to userspace)
+ * @release_list: list where delete peer should be appended
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+static int ovpn_peer_del_mp(struct ovpn_peer *peer,
+ enum ovpn_del_peer_reason reason,
+ struct llist_head *release_list)
+{
+ struct ovpn_peer *tmp;
+ int ret = -ENOENT;
+
+ lockdep_assert_held(&peer->ovpn->lock);
+
+ tmp = ovpn_peer_get_by_id(peer->ovpn, peer->id);
+ if (tmp == peer) {
+ ovpn_peer_remove(peer, reason, release_list);
+ ret = 0;
+ }
+
+ if (tmp)
+ ovpn_peer_put(tmp);
+
+ return ret;
}
/**
@@ -446,6 +571,9 @@ int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason)
spin_lock_bh(&peer->ovpn->lock);
switch (peer->ovpn->mode) {
+ case OVPN_MODE_MP:
+ ret = ovpn_peer_del_mp(peer, reason, &release_list);
+ break;
case OVPN_MODE_P2P:
ret = ovpn_peer_del_p2p(peer, reason, &release_list);
break;
@@ -463,8 +591,8 @@ int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason)
* @sk: if not NULL, release peer only if it's using this specific socket
* @reason: the reason for releasing the peer
*/
-void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, struct sock *sk,
- enum ovpn_del_peer_reason reason)
+static void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, struct sock *sk,
+ enum ovpn_del_peer_reason reason)
{
struct ovpn_socket *ovpn_sock;
LLIST_HEAD(release_list);
@@ -490,3 +618,52 @@ void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, struct sock *sk,
ovpn_peer_remove(peer, reason, &release_list);
unlock_ovpn(ovpn, &release_list);
}
+
+static void ovpn_peers_release_mp(struct ovpn_priv *ovpn, struct sock *sk,
+ enum ovpn_del_peer_reason reason)
+{
+ struct ovpn_socket *ovpn_sock;
+ LLIST_HEAD(release_list);
+ struct ovpn_peer *peer;
+ struct hlist_node *tmp;
+ int bkt;
+
+ spin_lock_bh(&ovpn->lock);
+ hash_for_each_safe(ovpn->peers->by_id, bkt, tmp, peer, hash_entry_id) {
+ bool remove = true;
+
+ /* if a socket was passed as argument, skip all peers except
+ * those using it
+ */
+ if (sk) {
+ rcu_read_lock();
+ ovpn_sock = rcu_dereference(peer->sock);
+ remove = ovpn_sock && ovpn_sock->sock->sk == sk;
+ rcu_read_unlock();
+ }
+
+ if (remove)
+ ovpn_peer_remove(peer, reason, &release_list);
+ }
+ unlock_ovpn(ovpn, &release_list);
+}
+
+/**
+ * ovpn_peers_free - free all peers in the instance
+ * @ovpn: the instance whose peers should be released
+ * @sk: if not NULL, only peers using this socket are removed and the socket
+ * is released immediately
+ * @reason: the reason for releasing all peers
+ */
+void ovpn_peers_free(struct ovpn_priv *ovpn, struct sock *sk,
+ enum ovpn_del_peer_reason reason)
+{
+ switch (ovpn->mode) {
+ case OVPN_MODE_P2P:
+ ovpn_peer_release_p2p(ovpn, sk, reason);
+ break;
+ case OVPN_MODE_MP:
+ ovpn_peers_release_mp(ovpn, sk, reason);
+ break;
+ }
+}
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index 5ef00ba6523d7bf6608adb86fa7c7029f559ce2a..2a3b1031f58dd73925a9ed74aed7ac4cb7b8c4c5 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -25,6 +25,10 @@
* @vpn_addrs: IP addresses assigned over the tunnel
* @vpn_addrs.ipv4: IPv4 assigned to peer on the tunnel
* @vpn_addrs.ipv6: IPv6 assigned to peer on the tunnel
+ * @hash_entry_id: entry in the peer ID hashtable
+ * @hash_entry_addr4: entry in the peer IPv4 hashtable
+ * @hash_entry_addr6: entry in the peer IPv6 hashtable
+ * @hash_entry_transp_addr: entry in the peer transport address hashtable
* @sock: the socket being used to talk to this peer
* @tcp: keeps track of TCP specific state
* @tcp.strp: stream parser context (TCP only)
@@ -57,6 +61,10 @@ struct ovpn_peer {
struct in_addr ipv4;
struct in6_addr ipv6;
} vpn_addrs;
+ struct hlist_node hash_entry_id;
+ struct hlist_nulls_node hash_entry_addr4;
+ struct hlist_nulls_node hash_entry_addr6;
+ struct hlist_nulls_node hash_entry_transp_addr;
struct ovpn_socket __rcu *sock;
struct {
@@ -117,8 +125,8 @@ static inline void ovpn_peer_put(struct ovpn_peer *peer)
struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id);
int ovpn_peer_add(struct ovpn_priv *ovpn, struct ovpn_peer *peer);
int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason);
-void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, struct sock *sk,
- enum ovpn_del_peer_reason reason);
+void ovpn_peers_free(struct ovpn_priv *ovpn, struct sock *sock,
+ enum ovpn_del_peer_reason reason);
struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_priv *ovpn,
struct sk_buff *skb);
diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c
index 6f4b51089033a8d806eede0a63f62b239197af0b..3367feb5cf725e41d01e140e838072e93f7fd4ef 100644
--- a/drivers/net/ovpn/udp.c
+++ b/drivers/net/ovpn/udp.c
@@ -370,9 +370,7 @@ static void ovpn_udp_encap_destroy(struct sock *sk)
ovpn = sock->ovpn;
rcu_read_unlock();
- if (ovpn->mode == OVPN_MODE_P2P)
- ovpn_peer_release_p2p(ovpn, sk,
- OVPN_DEL_PEER_REASON_TRANSPORT_DISCONNECT);
+ ovpn_peers_free(ovpn, sk, OVPN_DEL_PEER_REASON_TRANSPORT_DISCONNECT);
}
/**
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 15/24] ovpn: implement peer lookup logic
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (13 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 14/24] ovpn: implement multi-peer support Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 16/24] ovpn: implement keepalive mechanism Antonio Quartulli
` (8 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
In a multi-peer scenario there are a number of situations when a
specific peer needs to be looked up.
We may want to lookup a peer by:
1. its ID
2. its VPN destination IP
3. its transport IP/port couple
For each of the above, there is a specific routing table referencing all
peers for fast look up.
Case 2. is a bit special in the sense that an outgoing packet may not be
sent to the peer VPN IP directly, but rather to a network behind it. For
this reason we first perform a nexthop lookup in the system routing
table and then we use the retrieved nexthop as peer search key.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/peer.c | 301 ++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 291 insertions(+), 10 deletions(-)
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index bed2e591c000c4efecdcd92db484e590f97f9f7f..2d6cecc28c5d1f7d5516f7f89bc0ba274c72d5e1 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -10,6 +10,7 @@
#include <linux/skbuff.h>
#include <linux/list.h>
#include <linux/hashtable.h>
+#include <net/ip6_route.h>
#include "ovpnpriv.h"
#include "bind.h"
@@ -150,6 +151,121 @@ static int ovpn_peer_skb_to_sockaddr(struct sk_buff *skb,
return -1;
}
+/**
+ * ovpn_nexthop_from_skb4 - retrieve IPv4 nexthop for outgoing skb
+ * @skb: the outgoing packet
+ *
+ * Return: the IPv4 of the nexthop
+ */
+static __be32 ovpn_nexthop_from_skb4(struct sk_buff *skb)
+{
+ const struct rtable *rt = skb_rtable(skb);
+
+ if (rt && rt->rt_uses_gateway)
+ return rt->rt_gw4;
+
+ return ip_hdr(skb)->daddr;
+}
+
+/**
+ * ovpn_nexthop_from_skb6 - retrieve IPv6 nexthop for outgoing skb
+ * @skb: the outgoing packet
+ *
+ * Return: the IPv6 of the nexthop
+ */
+static struct in6_addr ovpn_nexthop_from_skb6(struct sk_buff *skb)
+{
+ const struct rt6_info *rt = skb_rt6_info(skb);
+
+ if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))
+ return ipv6_hdr(skb)->daddr;
+
+ return rt->rt6i_gateway;
+}
+
+/* variable name __tbl2 needs to be different from __tbl1
+ * in the macro below to avoid confusing clang
+ */
+#define ovpn_get_hash_slot(_tbl, _key, _key_len) ({ \
+ typeof(_tbl) *__tbl2 = &(_tbl); \
+ jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl2); \
+})
+
+#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \
+ typeof(_tbl) *__tbl1 = &(_tbl); \
+ &(*__tbl1)[ovpn_get_hash_slot(*__tbl1, _key, _key_len)];\
+})
+
+/**
+ * ovpn_peer_get_by_vpn_addr4 - retrieve peer by its VPN IPv4 address
+ * @ovpn: the openvpn instance to search
+ * @addr: VPN IPv4 to use as search key
+ *
+ * Refcounter is not increased for the returned peer.
+ *
+ * Return: the peer if found or NULL otherwise
+ */
+static struct ovpn_peer *ovpn_peer_get_by_vpn_addr4(struct ovpn_priv *ovpn,
+ __be32 addr)
+{
+ struct hlist_nulls_head *nhead;
+ struct hlist_nulls_node *ntmp;
+ struct ovpn_peer *tmp;
+ unsigned int slot;
+
+begin:
+ slot = ovpn_get_hash_slot(ovpn->peers->by_vpn_addr4, &addr,
+ sizeof(addr));
+ nhead = &ovpn->peers->by_vpn_addr4[slot];
+
+ hlist_nulls_for_each_entry_rcu(tmp, ntmp, nhead, hash_entry_addr4)
+ if (addr == tmp->vpn_addrs.ipv4.s_addr)
+ return tmp;
+
+ /* item may have moved during lookup - check nulls and restart
+ * if that's the case
+ */
+ if (get_nulls_value(ntmp) != slot)
+ goto begin;
+
+ return NULL;
+}
+
+/**
+ * ovpn_peer_get_by_vpn_addr6 - retrieve peer by its VPN IPv6 address
+ * @ovpn: the openvpn instance to search
+ * @addr: VPN IPv6 to use as search key
+ *
+ * Refcounter is not increased for the returned peer.
+ *
+ * Return: the peer if found or NULL otherwise
+ */
+static struct ovpn_peer *ovpn_peer_get_by_vpn_addr6(struct ovpn_priv *ovpn,
+ struct in6_addr *addr)
+{
+ struct hlist_nulls_head *nhead;
+ struct hlist_nulls_node *ntmp;
+ struct ovpn_peer *tmp;
+ unsigned int slot;
+
+begin:
+ slot = ovpn_get_hash_slot(ovpn->peers->by_vpn_addr6, addr,
+ sizeof(*addr));
+ nhead = &ovpn->peers->by_vpn_addr6[slot];
+
+ hlist_nulls_for_each_entry_rcu(tmp, ntmp, nhead, hash_entry_addr6)
+ if (ipv6_addr_equal(addr, &tmp->vpn_addrs.ipv6))
+ return tmp;
+
+ /* item may have moved during lookup - check nulls and restart
+ * if that's the case
+ */
+ if (get_nulls_value(ntmp) != slot)
+ goto begin;
+
+ return NULL;
+}
+
/**
* ovpn_peer_transp_match - check if sockaddr and peer binding match
* @peer: the peer to get the binding from
@@ -227,14 +343,43 @@ ovpn_peer_get_by_transp_addr_p2p(struct ovpn_priv *ovpn,
struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_priv *ovpn,
struct sk_buff *skb)
{
- struct ovpn_peer *peer = NULL;
+ struct ovpn_peer *tmp, *peer = NULL;
struct sockaddr_storage ss = { 0 };
+ struct hlist_nulls_head *nhead;
+ struct hlist_nulls_node *ntmp;
+ unsigned int slot;
+ ssize_t sa_len;
- if (unlikely(!ovpn_peer_skb_to_sockaddr(skb, &ss)))
+ sa_len = ovpn_peer_skb_to_sockaddr(skb, &ss);
+ if (unlikely(sa_len < 0))
return NULL;
if (ovpn->mode == OVPN_MODE_P2P)
- peer = ovpn_peer_get_by_transp_addr_p2p(ovpn, &ss);
+ return ovpn_peer_get_by_transp_addr_p2p(ovpn, &ss);
+
+ rcu_read_lock();
+begin:
+ slot = ovpn_get_hash_slot(ovpn->peers->by_transp_addr, &ss, sa_len);
+ nhead = &ovpn->peers->by_transp_addr[slot];
+
+ hlist_nulls_for_each_entry_rcu(tmp, ntmp, nhead,
+ hash_entry_transp_addr) {
+ if (!ovpn_peer_transp_match(tmp, &ss))
+ continue;
+
+ if (!ovpn_peer_hold(tmp))
+ continue;
+
+ peer = tmp;
+ break;
+ }
+
+ /* item may have moved during lookup - check nulls and restart
+ * if that's the case
+ */
+ if (!peer && get_nulls_value(ntmp) != slot)
+ goto begin;
+ rcu_read_unlock();
return peer;
}
@@ -269,10 +414,27 @@ static struct ovpn_peer *ovpn_peer_get_by_id_p2p(struct ovpn_priv *ovpn,
*/
struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_priv *ovpn, u32 peer_id)
{
- struct ovpn_peer *peer = NULL;
+ struct ovpn_peer *tmp, *peer = NULL;
+ struct hlist_head *head;
if (ovpn->mode == OVPN_MODE_P2P)
- peer = ovpn_peer_get_by_id_p2p(ovpn, peer_id);
+ return ovpn_peer_get_by_id_p2p(ovpn, peer_id);
+
+ head = ovpn_get_hash_head(ovpn->peers->by_id, &peer_id,
+ sizeof(peer_id));
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(tmp, head, hash_entry_id) {
+ if (tmp->id != peer_id)
+ continue;
+
+ if (!ovpn_peer_hold(tmp))
+ continue;
+
+ peer = tmp;
+ break;
+ }
+ rcu_read_unlock();
return peer;
}
@@ -330,6 +492,8 @@ struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_priv *ovpn,
struct sk_buff *skb)
{
struct ovpn_peer *peer = NULL;
+ struct in6_addr addr6;
+ __be32 addr4;
/* in P2P mode, no matter the destination, packets are always sent to
* the single peer listening on the other side
@@ -340,11 +504,109 @@ struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_priv *ovpn,
if (unlikely(peer && !ovpn_peer_hold(peer)))
peer = NULL;
rcu_read_unlock();
+ return peer;
}
+ rcu_read_lock();
+ switch (skb->protocol) {
+ case htons(ETH_P_IP):
+ addr4 = ovpn_nexthop_from_skb4(skb);
+ peer = ovpn_peer_get_by_vpn_addr4(ovpn, addr4);
+ break;
+ case htons(ETH_P_IPV6):
+ addr6 = ovpn_nexthop_from_skb6(skb);
+ peer = ovpn_peer_get_by_vpn_addr6(ovpn, &addr6);
+ break;
+ }
+
+ if (unlikely(peer && !ovpn_peer_hold(peer)))
+ peer = NULL;
+ rcu_read_unlock();
+
return peer;
}
+/**
+ * ovpn_nexthop_from_rt4 - look up the IPv4 nexthop for the given destination
+ * @ovpn: the private data representing the current VPN session
+ * @dest: the destination to be looked up
+ *
+ * Looks up in the IPv4 system routing table the IP of the nexthop to be used
+ * to reach the destination passed as argument. If no nexthop can be found, the
+ * destination itself is returned as it probably has to be used as nexthop.
+ *
+ * Return: the IP of the next hop if found or dest itself otherwise
+ */
+static __be32 ovpn_nexthop_from_rt4(struct ovpn_priv *ovpn, __be32 dest)
+{
+ struct rtable *rt;
+ struct flowi4 fl = {
+ .daddr = dest
+ };
+
+ rt = ip_route_output_flow(dev_net(ovpn->dev), &fl, NULL);
+ if (IS_ERR(rt)) {
+ net_dbg_ratelimited("%s: no route to host %pI4\n",
+ netdev_name(ovpn->dev), &dest);
+ /* if we end up here this packet is probably going to be
+ * thrown away later
+ */
+ return dest;
+ }
+
+ if (!rt->rt_uses_gateway)
+ goto out;
+
+ dest = rt->rt_gw4;
+out:
+ ip_rt_put(rt);
+ return dest;
+}
+
+/**
+ * ovpn_nexthop_from_rt6 - look up the IPv6 nexthop for the given destination
+ * @ovpn: the private data representing the current VPN session
+ * @dest: the destination to be looked up
+ *
+ * Looks up in the IPv6 system routing table the IP of the nexthop to be used
+ * to reach the destination passed as argument. If no nexthop can be found, the
+ * destination itself is returned as it probably has to be used as nexthop.
+ *
+ * Return: the IP of the next hop if found or dest itself otherwise
+ */
+static struct in6_addr ovpn_nexthop_from_rt6(struct ovpn_priv *ovpn,
+ struct in6_addr dest)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+ struct dst_entry *entry;
+ struct rt6_info *rt;
+ struct flowi6 fl = {
+ .daddr = dest,
+ };
+
+ entry = ipv6_stub->ipv6_dst_lookup_flow(dev_net(ovpn->dev), NULL, &fl,
+ NULL);
+ if (IS_ERR(entry)) {
+ net_dbg_ratelimited("%s: no route to host %pI6c\n",
+ netdev_name(ovpn->dev), &dest);
+ /* if we end up here this packet is probably going to be
+ * thrown away later
+ */
+ return dest;
+ }
+
+ rt = dst_rt6_info(entry);
+
+ if (!(rt->rt6i_flags & RTF_GATEWAY))
+ goto out;
+
+ dest = rt->rt6i_gateway;
+out:
+ dst_release((struct dst_entry *)rt);
+#endif
+ return dest;
+}
+
/**
* ovpn_peer_check_by_src - check that skb source is routed via peer
* @ovpn: the openvpn instance to search
@@ -357,21 +619,40 @@ bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb,
struct ovpn_peer *peer)
{
bool match = false;
+ struct in6_addr addr6;
+ __be32 addr4;
if (ovpn->mode == OVPN_MODE_P2P) {
/* in P2P mode, no matter the destination, packets are always
* sent to the single peer listening on the other side
*/
- match = (peer == rcu_access_pointer(ovpn->peer));
+ return peer == rcu_access_pointer(ovpn->peer);
+ }
+
+ /* This function performs a reverse path check, therefore we now
+ * lookup the nexthop we would use if we wanted to route a packet
+ * to the source IP. If the nexthop matches the sender we know the
+ * latter is valid and we allow the packet to come in
+ */
+
+ switch (skb->protocol) {
+ case htons(ETH_P_IP):
+ addr4 = ovpn_nexthop_from_rt4(ovpn, ip_hdr(skb)->saddr);
+ rcu_read_lock();
+ match = (peer == ovpn_peer_get_by_vpn_addr4(ovpn, addr4));
+ rcu_read_unlock();
+ break;
+ case htons(ETH_P_IPV6):
+ addr6 = ovpn_nexthop_from_rt6(ovpn, ipv6_hdr(skb)->saddr);
+ rcu_read_lock();
+ match = (peer == ovpn_peer_get_by_vpn_addr6(ovpn, &addr6));
+ rcu_read_unlock();
+ break;
}
return match;
}
-#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \
- typeof(_tbl) *__tbl = &(_tbl); \
- (&(*__tbl)[jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl)]); }) \
-
/**
* ovpn_peer_add_mp - add peer to related tables in a MP instance
* @ovpn: the instance to add the peer to
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 16/24] ovpn: implement keepalive mechanism
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (14 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 15/24] ovpn: implement peer lookup logic Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 17/24] ovpn: add support for updating local UDP endpoint Antonio Quartulli
` (7 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
OpenVPN supports configuring a periodic keepalive packet.
message to allow the remote endpoint detect link failures.
This change implements the keepalive sending and timer expiring logic.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/io.c | 74 ++++++++++++++++
drivers/net/ovpn/io.h | 5 ++
drivers/net/ovpn/main.c | 3 +
drivers/net/ovpn/ovpnpriv.h | 2 +
drivers/net/ovpn/peer.c | 205 ++++++++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/peer.h | 21 ++++-
6 files changed, 308 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index 729f49ff6ce8001c2bbe804db0a617a2cc8965a8..6ee1a40082ef637285d7f7f8183c53140583b716 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -27,6 +27,33 @@
#include "skb.h"
#include "socket.h"
+const unsigned char ovpn_keepalive_message[OVPN_KEEPALIVE_SIZE] = {
+ 0x2a, 0x18, 0x7b, 0xf3, 0x64, 0x1e, 0xb4, 0xcb,
+ 0x07, 0xed, 0x2d, 0x0a, 0x98, 0x1f, 0xc7, 0x48
+};
+
+/**
+ * ovpn_is_keepalive - check if skb contains a keepalive message
+ * @skb: packet to check
+ *
+ * Assumes that the first byte of skb->data is defined.
+ *
+ * Return: true if skb contains a keepalive or false otherwise
+ */
+static bool ovpn_is_keepalive(struct sk_buff *skb)
+{
+ if (*skb->data != ovpn_keepalive_message[0])
+ return false;
+
+ if (skb->len != OVPN_KEEPALIVE_SIZE)
+ return false;
+
+ if (!pskb_may_pull(skb, OVPN_KEEPALIVE_SIZE))
+ return false;
+
+ return !memcmp(skb->data, ovpn_keepalive_message, OVPN_KEEPALIVE_SIZE);
+}
+
/* Called after decrypt to write the IP packet to the device.
* This method is expected to manage/free the skb.
*/
@@ -107,6 +134,9 @@ void ovpn_decrypt_post(void *data, int ret)
goto drop;
}
+ /* keep track of last received authenticated packet for keepalive */
+ WRITE_ONCE(peer->last_recv, ktime_get_real_seconds());
+
/* point to encapsulated IP packet */
__skb_pull(skb, payload_offset);
@@ -124,6 +154,13 @@ void ovpn_decrypt_post(void *data, int ret)
goto drop;
}
+ if (ovpn_is_keepalive(skb)) {
+ net_dbg_ratelimited("%s: ping received from peer %u\n",
+ netdev_name(peer->ovpn->dev),
+ peer->id);
+ goto drop_nocount;
+ }
+
net_info_ratelimited("%s: unsupported protocol received from peer %u\n",
netdev_name(peer->ovpn->dev), peer->id);
goto drop;
@@ -149,6 +186,7 @@ void ovpn_decrypt_post(void *data, int ret)
drop:
if (unlikely(skb))
dev_core_stats_rx_dropped_inc(peer->ovpn->dev);
+drop_nocount:
if (likely(peer))
ovpn_peer_put(peer);
if (likely(ks))
@@ -233,6 +271,8 @@ void ovpn_encrypt_post(void *data, int ret)
}
ovpn_peer_stats_increment_tx(&peer->link_stats, orig_len);
+ /* keep track of last sent packet for keepalive */
+ WRITE_ONCE(peer->last_sent, ktime_get_real_seconds());
/* skb passed down the stack - don't free it */
skb = NULL;
err_unlock:
@@ -365,3 +405,37 @@ netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev)
kfree_skb_list(skb);
return NET_XMIT_DROP;
}
+
+/**
+ * ovpn_xmit_special - encrypt and transmit an out-of-band message to peer
+ * @peer: peer to send the message to
+ * @data: message content
+ * @len: message length
+ *
+ * Assumes that caller holds a reference to peer, which will be
+ * passed to ovpn_send()
+ */
+void ovpn_xmit_special(struct ovpn_peer *peer, const void *data,
+ const unsigned int len)
+{
+ struct ovpn_priv *ovpn;
+ struct sk_buff *skb;
+
+ ovpn = peer->ovpn;
+ if (unlikely(!ovpn)) {
+ ovpn_peer_put(peer);
+ return;
+ }
+
+ skb = alloc_skb(256 + len, GFP_ATOMIC);
+ if (unlikely(!skb)) {
+ ovpn_peer_put(peer);
+ return;
+ }
+
+ skb_reserve(skb, 128);
+ skb->priority = TC_PRIO_BESTEFFORT;
+ __skb_put_data(skb, data, len);
+
+ ovpn_send(ovpn, skb, peer);
+}
diff --git a/drivers/net/ovpn/io.h b/drivers/net/ovpn/io.h
index 5143104b2c4b896a030ec4a8c8aea7015f40ef02..db9e10f9077c4738ee79e5723e2a4bf5ef72f633 100644
--- a/drivers/net/ovpn/io.h
+++ b/drivers/net/ovpn/io.h
@@ -19,9 +19,14 @@
/* max padding required by encryption */
#define OVPN_MAX_PADDING 16
+#define OVPN_KEEPALIVE_SIZE 16
+extern const unsigned char ovpn_keepalive_message[OVPN_KEEPALIVE_SIZE];
+
netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev);
void ovpn_recv(struct ovpn_peer *peer, struct sk_buff *skb);
+void ovpn_xmit_special(struct ovpn_peer *peer, const void *data,
+ const unsigned int len);
void ovpn_encrypt_post(void *data, int ret);
void ovpn_decrypt_post(void *data, int ret);
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index 333a025a69094f1be3fb0a7a934da0cdb5abdcde..dd05d0fe7a2d139bda55ebd68b9e1d78f5c00af9 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -194,6 +194,7 @@ static int ovpn_newlink(struct net_device *dev,
ovpn->dev = dev;
ovpn->mode = mode;
spin_lock_init(&ovpn->lock);
+ INIT_DELAYED_WORK(&ovpn->keepalive_work, ovpn_peer_keepalive_work);
/* turn carrier explicitly off after registration, this way state is
* clearly defined
@@ -253,6 +254,8 @@ static int ovpn_netdev_notifier_call(struct notifier_block *nb,
netif_carrier_off(dev);
ovpn->registered = false;
+
+ cancel_delayed_work_sync(&ovpn->keepalive_work);
ovpn_peers_free(ovpn, NULL, OVPN_DEL_PEER_REASON_TEARDOWN);
break;
case NETDEV_POST_INIT:
diff --git a/drivers/net/ovpn/ovpnpriv.h b/drivers/net/ovpn/ovpnpriv.h
index b26ad97215a3d42242ba349b348c2749f570797c..5403cdc99a67ca91604d1c3cefdea76dca83a44a 100644
--- a/drivers/net/ovpn/ovpnpriv.h
+++ b/drivers/net/ovpn/ovpnpriv.h
@@ -41,6 +41,7 @@ struct ovpn_peer_collection {
* @peers: data structures holding multi-peer references
* @peer: in P2P mode, this is the only remote peer
* @gro_cells: pointer to the Generic Receive Offload cell
+ * @keepalive_work: struct used to schedule keepalive periodic job
*/
struct ovpn_priv {
struct net_device *dev;
@@ -50,6 +51,7 @@ struct ovpn_priv {
struct ovpn_peer_collection *peers;
struct ovpn_peer __rcu *peer;
struct gro_cells gro_cells;
+ struct delayed_work keepalive_work;
};
#endif /* _NET_OVPN_OVPNSTRUCT_H_ */
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 2d6cecc28c5d1f7d5516f7f89bc0ba274c72d5e1..45e87ac155b554044388490a403f64c777d283a6 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -36,6 +36,52 @@ static void unlock_ovpn(struct ovpn_priv *ovpn,
}
}
+/**
+ * ovpn_peer_keepalive_set - configure keepalive values for peer
+ * @peer: the peer to configure
+ * @interval: outgoing keepalive interval
+ * @timeout: incoming keepalive timeout
+ */
+void ovpn_peer_keepalive_set(struct ovpn_peer *peer, u32 interval, u32 timeout)
+{
+ time64_t now = ktime_get_real_seconds();
+
+ netdev_dbg(peer->ovpn->dev,
+ "scheduling keepalive for peer %u: interval=%u timeout=%u\n",
+ peer->id, interval, timeout);
+
+ peer->keepalive_interval = interval;
+ WRITE_ONCE(peer->last_sent, now);
+ peer->keepalive_xmit_exp = now + interval;
+
+ peer->keepalive_timeout = timeout;
+ WRITE_ONCE(peer->last_recv, now);
+ peer->keepalive_recv_exp = now + timeout;
+
+ /* now that interval and timeout have been changed, kick
+ * off the worker so that the next delay can be recomputed
+ */
+ mod_delayed_work(system_wq, &peer->ovpn->keepalive_work, 0);
+}
+
+/**
+ * ovpn_peer_keepalive_send - periodic worker sending keepalive packets
+ * @work: pointer to the work member of the related peer object
+ *
+ * NOTE: the reference to peer is not dropped because it gets inherited
+ * by ovpn_xmit_special()
+ */
+static void ovpn_peer_keepalive_send(struct work_struct *work)
+{
+ struct ovpn_peer *peer = container_of(work, struct ovpn_peer,
+ keepalive_work);
+
+ local_bh_disable();
+ ovpn_xmit_special(peer, ovpn_keepalive_message,
+ sizeof(ovpn_keepalive_message));
+ local_bh_enable();
+}
+
/**
* ovpn_peer_new - allocate and initialize a new peer object
* @ovpn: the openvpn instance inside which the peer should be created
@@ -65,6 +111,7 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id)
kref_init(&peer->refcount);
ovpn_peer_stats_init(&peer->vpn_stats);
ovpn_peer_stats_init(&peer->link_stats);
+ INIT_WORK(&peer->keepalive_work, ovpn_peer_keepalive_send);
ret = dst_cache_init(&peer->dst_cache, GFP_KERNEL);
if (ret < 0) {
@@ -948,3 +995,161 @@ void ovpn_peers_free(struct ovpn_priv *ovpn, struct sock *sk,
break;
}
}
+
+static time64_t ovpn_peer_keepalive_work_single(struct ovpn_peer *peer,
+ time64_t now,
+ struct llist_head *release_list)
+{
+ time64_t last_recv, last_sent, next_run1, next_run2;
+ unsigned long timeout, interval;
+ bool expired;
+
+ spin_lock_bh(&peer->lock);
+ /* we expect both timers to be configured at the same time,
+ * therefore bail out if either is not set
+ */
+ if (!peer->keepalive_timeout || !peer->keepalive_interval) {
+ spin_unlock_bh(&peer->lock);
+ return 0;
+ }
+
+ /* check for peer timeout */
+ expired = false;
+ timeout = peer->keepalive_timeout;
+ last_recv = READ_ONCE(peer->last_recv);
+ if (now < last_recv + timeout) {
+ peer->keepalive_recv_exp = last_recv + timeout;
+ next_run1 = peer->keepalive_recv_exp;
+ } else if (peer->keepalive_recv_exp > now) {
+ next_run1 = peer->keepalive_recv_exp;
+ } else {
+ expired = true;
+ }
+
+ if (expired) {
+ /* peer is dead -> kill it and move on */
+ spin_unlock_bh(&peer->lock);
+ netdev_dbg(peer->ovpn->dev, "peer %u expired\n",
+ peer->id);
+ ovpn_peer_remove(peer, OVPN_DEL_PEER_REASON_EXPIRED,
+ release_list);
+ return 0;
+ }
+
+ /* check for peer keepalive */
+ expired = false;
+ interval = peer->keepalive_interval;
+ last_sent = READ_ONCE(peer->last_sent);
+ if (now < last_sent + interval) {
+ peer->keepalive_xmit_exp = last_sent + interval;
+ next_run2 = peer->keepalive_xmit_exp;
+ } else if (peer->keepalive_xmit_exp > now) {
+ next_run2 = peer->keepalive_xmit_exp;
+ } else {
+ expired = true;
+ next_run2 = now + interval;
+ }
+ spin_unlock_bh(&peer->lock);
+
+ if (expired) {
+ /* a keepalive packet is required */
+ netdev_dbg(peer->ovpn->dev,
+ "sending keepalive to peer %u\n",
+ peer->id);
+ if (schedule_work(&peer->keepalive_work))
+ ovpn_peer_hold(peer);
+ }
+
+ if (next_run1 < next_run2)
+ return next_run1;
+
+ return next_run2;
+}
+
+static time64_t ovpn_peer_keepalive_work_mp(struct ovpn_priv *ovpn,
+ time64_t now,
+ struct llist_head *release_list)
+{
+ time64_t tmp_next_run, next_run = 0;
+ struct hlist_node *tmp;
+ struct ovpn_peer *peer;
+ int bkt;
+
+ lockdep_assert_held(&ovpn->lock);
+
+ hash_for_each_safe(ovpn->peers->by_id, bkt, tmp, peer, hash_entry_id) {
+ tmp_next_run = ovpn_peer_keepalive_work_single(peer, now,
+ release_list);
+ if (!tmp_next_run)
+ continue;
+
+ /* the next worker run will be scheduled based on the shortest
+ * required interval across all peers
+ */
+ if (!next_run || tmp_next_run < next_run)
+ next_run = tmp_next_run;
+ }
+
+ return next_run;
+}
+
+static time64_t ovpn_peer_keepalive_work_p2p(struct ovpn_priv *ovpn,
+ time64_t now,
+ struct llist_head *release_list)
+{
+ struct ovpn_peer *peer;
+ time64_t next_run = 0;
+
+ lockdep_assert_held(&ovpn->lock);
+
+ peer = rcu_dereference_protected(ovpn->peer,
+ lockdep_is_held(&ovpn->lock));
+ if (peer)
+ next_run = ovpn_peer_keepalive_work_single(peer, now,
+ release_list);
+
+ return next_run;
+}
+
+/**
+ * ovpn_peer_keepalive_work - run keepalive logic on each known peer
+ * @work: pointer to the work member of the related ovpn object
+ *
+ * Each peer has two timers (if configured):
+ * 1. peer timeout: when no data is received for a certain interval,
+ * the peer is considered dead and it gets killed.
+ * 2. peer keepalive: when no data is sent to a certain peer for a
+ * certain interval, a special 'keepalive' packet is explicitly sent.
+ *
+ * This function iterates across the whole peer collection while
+ * checking the timers described above.
+ */
+void ovpn_peer_keepalive_work(struct work_struct *work)
+{
+ struct ovpn_priv *ovpn = container_of(work, struct ovpn_priv,
+ keepalive_work.work);
+ time64_t next_run = 0, now = ktime_get_real_seconds();
+ LLIST_HEAD(release_list);
+
+ spin_lock_bh(&ovpn->lock);
+ switch (ovpn->mode) {
+ case OVPN_MODE_MP:
+ next_run = ovpn_peer_keepalive_work_mp(ovpn, now,
+ &release_list);
+ break;
+ case OVPN_MODE_P2P:
+ next_run = ovpn_peer_keepalive_work_p2p(ovpn, now,
+ &release_list);
+ break;
+ }
+
+ /* prevent rearming if the interface is being destroyed */
+ if (next_run > 0 && ovpn->registered) {
+ netdev_dbg(ovpn->dev,
+ "scheduling keepalive work: now=%llu next_run=%llu delta=%llu\n",
+ next_run, now, next_run - now);
+ schedule_delayed_work(&ovpn->keepalive_work,
+ (next_run - now) * HZ);
+ }
+ unlock_ovpn(ovpn, &release_list);
+}
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index 2a3b1031f58dd73925a9ed74aed7ac4cb7b8c4c5..e747c4b210642db990222986a80bb37c9a0413fe 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -45,13 +45,20 @@
* @crypto: the crypto configuration (ciphers, keys, etc..)
* @dst_cache: cache for dst_entry used to send to peer
* @bind: remote peer binding
+ * @keepalive_interval: seconds after which a new keepalive should be sent
+ * @keepalive_xmit_exp: future timestamp when next keepalive should be sent
+ * @last_sent: timestamp of the last successfully sent packet
+ * @keepalive_timeout: seconds after which an inactive peer is considered dead
+ * @keepalive_recv_exp: future timestamp when the peer should expire
+ * @last_recv: timestamp of the last authenticated received packet
* @vpn_stats: per-peer in-VPN TX/RX stats
* @link_stats: per-peer link/transport TX/RX stats
* @delete_reason: why peer was deleted (i.e. timeout, transport error, ..)
- * @lock: protects binding to peer (bind)
+ * @lock: protects binding to peer (bind) and keepalive* fields
* @refcount: reference counter
* @rcu: used to free peer in an RCU safe way
* @release_entry: entry for the socket release list
+ * @keepalive_work: used to schedule keepalive sending
*/
struct ovpn_peer {
struct ovpn_priv *ovpn;
@@ -91,13 +98,20 @@ struct ovpn_peer {
struct ovpn_crypto_state crypto;
struct dst_cache dst_cache;
struct ovpn_bind __rcu *bind;
+ unsigned long keepalive_interval;
+ unsigned long keepalive_xmit_exp;
+ time64_t last_sent;
+ unsigned long keepalive_timeout;
+ unsigned long keepalive_recv_exp;
+ time64_t last_recv;
struct ovpn_peer_stats vpn_stats;
struct ovpn_peer_stats link_stats;
enum ovpn_del_peer_reason delete_reason;
- spinlock_t lock; /* protects bind */
+ spinlock_t lock; /* protects bind and keepalive* */
struct kref refcount;
struct rcu_head rcu;
struct llist_node release_entry;
+ struct work_struct keepalive_work;
};
/**
@@ -136,4 +150,7 @@ struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_priv *ovpn,
bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb,
struct ovpn_peer *peer);
+void ovpn_peer_keepalive_set(struct ovpn_peer *peer, u32 interval, u32 timeout);
+void ovpn_peer_keepalive_work(struct work_struct *work);
+
#endif /* _NET_OVPN_OVPNPEER_H_ */
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 17/24] ovpn: add support for updating local UDP endpoint
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (15 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 16/24] ovpn: implement keepalive mechanism Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 18/24] ovpn: add support for peer floating Antonio Quartulli
` (6 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
In case of UDP links, the local endpoint used to communicate with a
given peer may change without a connection restart.
Add support for learning the new address in case of change.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/peer.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/peer.h | 3 +++
2 files changed, 48 insertions(+)
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 45e87ac155b554044388490a403f64c777d283a6..1803359b833d5797728566fb976e253e2a85ea75 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -522,6 +522,51 @@ static void ovpn_peer_remove(struct ovpn_peer *peer,
llist_add(&peer->release_entry, release_list);
}
+/**
+ * ovpn_peer_update_local_endpoint - update local endpoint for peer
+ * @peer: peer to update the endpoint for
+ * @skb: incoming packet to retrieve the destination address (local) from
+ */
+void ovpn_peer_update_local_endpoint(struct ovpn_peer *peer,
+ struct sk_buff *skb)
+{
+ struct ovpn_bind *bind;
+
+ rcu_read_lock();
+ bind = rcu_dereference(peer->bind);
+ if (unlikely(!bind))
+ goto unlock;
+
+ spin_lock_bh(&peer->lock);
+ switch (skb->protocol) {
+ case htons(ETH_P_IP):
+ if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) {
+ net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n",
+ netdev_name(peer->ovpn->dev),
+ peer->id, &bind->local.ipv4.s_addr,
+ &ip_hdr(skb)->daddr);
+ bind->local.ipv4.s_addr = ip_hdr(skb)->daddr;
+ }
+ break;
+ case htons(ETH_P_IPV6):
+ if (unlikely(!ipv6_addr_equal(&bind->local.ipv6,
+ &ipv6_hdr(skb)->daddr))) {
+ net_dbg_ratelimited("%s: learning local IPv6 for peer %d (%pI6c -> %pI6c\n",
+ netdev_name(peer->ovpn->dev),
+ peer->id, &bind->local.ipv6,
+ &ipv6_hdr(skb)->daddr);
+ bind->local.ipv6 = ipv6_hdr(skb)->daddr;
+ }
+ break;
+ default:
+ break;
+ }
+ spin_unlock_bh(&peer->lock);
+
+unlock:
+ rcu_read_unlock();
+}
+
/**
* ovpn_peer_get_by_dst - Lookup peer to send skb to
* @ovpn: the private data representing the current VPN session
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index e747c4b210642db990222986a80bb37c9a0413fe..d90ccc313cc3af24ffa6df8bb41bca15fbb022ad 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -153,4 +153,7 @@ bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb,
void ovpn_peer_keepalive_set(struct ovpn_peer *peer, u32 interval, u32 timeout);
void ovpn_peer_keepalive_work(struct work_struct *work);
+void ovpn_peer_update_local_endpoint(struct ovpn_peer *peer,
+ struct sk_buff *skb);
+
#endif /* _NET_OVPN_OVPNPEER_H_ */
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 18/24] ovpn: add support for peer floating
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (16 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 17/24] ovpn: add support for updating local UDP endpoint Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 18:37 ` Sabrina Dubroca
2025-03-04 0:33 ` [PATCH v21 19/24] ovpn: implement peer add/get/dump/delete via netlink Antonio Quartulli
` (5 subsequent siblings)
23 siblings, 1 reply; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
A peer connected via UDP may change its IP address without reconnecting
(float).
Add support for detecting and updating the new peer IP/port in case of
floating.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/io.c | 8 ++
drivers/net/ovpn/peer.c | 243 ++++++++++++++++++++++++++++++++++++------------
drivers/net/ovpn/peer.h | 3 +-
3 files changed, 194 insertions(+), 60 deletions(-)
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index 6ee1a40082ef637285d7f7f8183c53140583b716..5b673eae255033b9d7d6e7890a46686403d7c222 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -96,6 +96,7 @@ void ovpn_decrypt_post(void *data, int ret)
struct ovpn_crypto_key_slot *ks;
unsigned int payload_offset = 0;
struct sk_buff *skb = data;
+ struct ovpn_socket *sock;
struct ovpn_peer *peer;
__be16 proto;
__be32 *pid;
@@ -137,6 +138,13 @@ void ovpn_decrypt_post(void *data, int ret)
/* keep track of last received authenticated packet for keepalive */
WRITE_ONCE(peer->last_recv, ktime_get_real_seconds());
+ rcu_read_lock();
+ sock = rcu_dereference(peer->sock);
+ if (sock && sock->sock->sk->sk_protocol == IPPROTO_UDP)
+ /* check if this peer changed local or remote endpoint */
+ ovpn_peer_endpoints_update(peer, skb);
+ rcu_read_unlock();
+
/* point to encapsulated IP packet */
__skb_pull(skb, payload_offset);
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 1803359b833d5797728566fb976e253e2a85ea75..156e45407e0a6e69f177a064053f81fe778a9dd8 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -127,6 +127,191 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id)
return peer;
}
+/**
+ * ovpn_peer_reset_sockaddr - recreate binding for peer
+ * @peer: peer to recreate the binding for
+ * @ss: sockaddr to use as remote endpoint for the binding
+ * @local_ip: local IP for the binding
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+static int ovpn_peer_reset_sockaddr(struct ovpn_peer *peer,
+ const struct sockaddr_storage *ss,
+ const u8 *local_ip)
+{
+ struct ovpn_bind *bind;
+ size_t ip_len;
+
+ lockdep_assert_held(&peer->lock);
+
+ /* create new ovpn_bind object */
+ bind = ovpn_bind_from_sockaddr(ss);
+ if (IS_ERR(bind))
+ return PTR_ERR(bind);
+
+ if (local_ip) {
+ if (ss->ss_family == AF_INET) {
+ ip_len = sizeof(struct in_addr);
+ } else if (ss->ss_family == AF_INET6) {
+ ip_len = sizeof(struct in6_addr);
+ } else {
+ net_dbg_ratelimited("%s: invalid family %u for remote endpoint for peer %u\n",
+ netdev_name(peer->ovpn->dev),
+ ss->ss_family, peer->id);
+ kfree(bind);
+ return -EINVAL;
+ }
+
+ memcpy(&bind->local, local_ip, ip_len);
+ }
+
+ /* set binding */
+ ovpn_bind_reset(peer, bind);
+
+ return 0;
+}
+
+/* variable name __tbl2 needs to be different from __tbl1
+ * in the macro below to avoid confusing clang
+ */
+#define ovpn_get_hash_slot(_tbl, _key, _key_len) ({ \
+ typeof(_tbl) *__tbl2 = &(_tbl); \
+ jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl2); \
+})
+
+#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \
+ typeof(_tbl) *__tbl1 = &(_tbl); \
+ &(*__tbl1)[ovpn_get_hash_slot(*__tbl1, _key, _key_len)];\
+})
+
+/**
+ * ovpn_peer_endpoints_update - update remote or local endpoint for peer
+ * @peer: peer to update the remote endpoint for
+ * @skb: incoming packet to retrieve the source/destination address from
+ */
+void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb)
+{
+ struct hlist_nulls_head *nhead;
+ struct sockaddr_storage ss;
+ const u8 *local_ip = NULL;
+ struct sockaddr_in6 *sa6;
+ struct sockaddr_in *sa;
+ struct ovpn_bind *bind;
+ size_t salen = 0;
+
+ spin_lock_bh(&peer->lock);
+ bind = rcu_dereference_protected(peer->bind,
+ lockdep_is_held(&peer->lock));
+ if (unlikely(!bind))
+ goto unlock;
+
+ switch (skb->protocol) {
+ case htons(ETH_P_IP):
+ /* float check */
+ if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) {
+ if (bind->remote.in4.sin_family == AF_INET)
+ local_ip = (u8 *)&bind->local;
+ sa = (struct sockaddr_in *)&ss;
+ sa->sin_family = AF_INET;
+ sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
+ sa->sin_port = udp_hdr(skb)->source;
+ salen = sizeof(*sa);
+ break;
+ }
+
+ /* local endpoint update */
+ if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) {
+ net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n",
+ netdev_name(peer->ovpn->dev),
+ peer->id, &bind->local.ipv4.s_addr,
+ &ip_hdr(skb)->daddr);
+ bind->local.ipv4.s_addr = ip_hdr(skb)->daddr;
+ }
+ break;
+ case htons(ETH_P_IPV6):
+ /* float check */
+ if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) {
+ if (bind->remote.in6.sin6_family == AF_INET6)
+ local_ip = (u8 *)&bind->local;
+ sa6 = (struct sockaddr_in6 *)&ss;
+ sa6->sin6_family = AF_INET6;
+ sa6->sin6_addr = ipv6_hdr(skb)->saddr;
+ sa6->sin6_port = udp_hdr(skb)->source;
+ sa6->sin6_scope_id = ipv6_iface_scope_id(&ipv6_hdr(skb)->saddr,
+ skb->skb_iif);
+ salen = sizeof(*sa6);
+ }
+
+ /* local endpoint update */
+ if (unlikely(!ipv6_addr_equal(&bind->local.ipv6,
+ &ipv6_hdr(skb)->daddr))) {
+ net_dbg_ratelimited("%s: learning local IPv6 for peer %d (%pI6c -> %pI6c\n",
+ netdev_name(peer->ovpn->dev),
+ peer->id, &bind->local.ipv6,
+ &ipv6_hdr(skb)->daddr);
+ bind->local.ipv6 = ipv6_hdr(skb)->daddr;
+ }
+ break;
+ default:
+ goto unlock;
+ }
+
+ /* if the peer did not float, we can bail out now */
+ if (likely(!salen))
+ goto unlock;
+
+ if (unlikely(ovpn_peer_reset_sockaddr(peer,
+ (struct sockaddr_storage *)&ss,
+ local_ip) < 0))
+ goto unlock;
+
+ net_dbg_ratelimited("%s: peer %d floated to %pIScp",
+ netdev_name(peer->ovpn->dev), peer->id, &ss);
+
+ spin_unlock_bh(&peer->lock);
+
+ /* rehashing is required only in MP mode as P2P has one peer
+ * only and thus there is no hashtable
+ */
+ if (peer->ovpn->mode == OVPN_MODE_MP) {
+ spin_lock_bh(&peer->ovpn->lock);
+ spin_lock_bh(&peer->lock);
+ bind = rcu_dereference_protected(peer->bind,
+ lockdep_is_held(&peer->lock));
+ if (unlikely(!bind)) {
+ spin_unlock_bh(&peer->lock);
+ spin_unlock_bh(&peer->ovpn->lock);
+ return;
+ }
+
+ /* his function may be invoked concurrently, therefore another
+ * float may have happened in parallel: perform rehashing
+ * using the peer->bind->remote directly as key
+ */
+
+ switch (bind->remote.in4.sin_family) {
+ case AF_INET:
+ salen = sizeof(*sa);
+ break;
+ case AF_INET6:
+ salen = sizeof(*sa6);
+ break;
+ }
+
+ /* remove old hashing */
+ hlist_nulls_del_init_rcu(&peer->hash_entry_transp_addr);
+ /* re-add with new transport address */
+ nhead = ovpn_get_hash_head(peer->ovpn->peers->by_transp_addr,
+ &bind->remote, salen);
+ hlist_nulls_add_head_rcu(&peer->hash_entry_transp_addr, nhead);
+ spin_unlock_bh(&peer->lock);
+ spin_unlock_bh(&peer->ovpn->lock);
+ }
+ return;
+unlock:
+ spin_unlock_bh(&peer->lock);
+}
+
/**
* ovpn_peer_release_rcu - RCU callback performing last peer release steps
* @head: RCU member of the ovpn_peer
@@ -230,19 +415,6 @@ static struct in6_addr ovpn_nexthop_from_skb6(struct sk_buff *skb)
return rt->rt6i_gateway;
}
-/* variable name __tbl2 needs to be different from __tbl1
- * in the macro below to avoid confusing clang
- */
-#define ovpn_get_hash_slot(_tbl, _key, _key_len) ({ \
- typeof(_tbl) *__tbl2 = &(_tbl); \
- jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl2); \
-})
-
-#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \
- typeof(_tbl) *__tbl1 = &(_tbl); \
- &(*__tbl1)[ovpn_get_hash_slot(*__tbl1, _key, _key_len)];\
-})
-
/**
* ovpn_peer_get_by_vpn_addr4 - retrieve peer by its VPN IPv4 address
* @ovpn: the openvpn instance to search
@@ -522,51 +694,6 @@ static void ovpn_peer_remove(struct ovpn_peer *peer,
llist_add(&peer->release_entry, release_list);
}
-/**
- * ovpn_peer_update_local_endpoint - update local endpoint for peer
- * @peer: peer to update the endpoint for
- * @skb: incoming packet to retrieve the destination address (local) from
- */
-void ovpn_peer_update_local_endpoint(struct ovpn_peer *peer,
- struct sk_buff *skb)
-{
- struct ovpn_bind *bind;
-
- rcu_read_lock();
- bind = rcu_dereference(peer->bind);
- if (unlikely(!bind))
- goto unlock;
-
- spin_lock_bh(&peer->lock);
- switch (skb->protocol) {
- case htons(ETH_P_IP):
- if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) {
- net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n",
- netdev_name(peer->ovpn->dev),
- peer->id, &bind->local.ipv4.s_addr,
- &ip_hdr(skb)->daddr);
- bind->local.ipv4.s_addr = ip_hdr(skb)->daddr;
- }
- break;
- case htons(ETH_P_IPV6):
- if (unlikely(!ipv6_addr_equal(&bind->local.ipv6,
- &ipv6_hdr(skb)->daddr))) {
- net_dbg_ratelimited("%s: learning local IPv6 for peer %d (%pI6c -> %pI6c\n",
- netdev_name(peer->ovpn->dev),
- peer->id, &bind->local.ipv6,
- &ipv6_hdr(skb)->daddr);
- bind->local.ipv6 = ipv6_hdr(skb)->daddr;
- }
- break;
- default:
- break;
- }
- spin_unlock_bh(&peer->lock);
-
-unlock:
- rcu_read_unlock();
-}
-
/**
* ovpn_peer_get_by_dst - Lookup peer to send skb to
* @ovpn: the private data representing the current VPN session
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index d90ccc313cc3af24ffa6df8bb41bca15fbb022ad..f1288734ff100ee76b0c41ebb6dc71725ea33261 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -153,7 +153,6 @@ bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb,
void ovpn_peer_keepalive_set(struct ovpn_peer *peer, u32 interval, u32 timeout);
void ovpn_peer_keepalive_work(struct work_struct *work);
-void ovpn_peer_update_local_endpoint(struct ovpn_peer *peer,
- struct sk_buff *skb);
+void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb);
#endif /* _NET_OVPN_OVPNPEER_H_ */
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* Re: [PATCH v21 18/24] ovpn: add support for peer floating
2025-03-04 0:33 ` [PATCH v21 18/24] ovpn: add support for peer floating Antonio Quartulli
@ 2025-03-04 18:37 ` Sabrina Dubroca
2025-03-04 23:19 ` Antonio Quartulli
0 siblings, 1 reply; 46+ messages in thread
From: Sabrina Dubroca @ 2025-03-04 18:37 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
2025-03-04, 01:33:48 +0100, Antonio Quartulli wrote:
> A peer connected via UDP may change its IP address without reconnecting
> (float).
Should that trigger a reset of the peer->dst_cache? And same when
userspace updates the remote address? Otherwise it seems we could be
stuck with a cached dst that cannot reach the peer.
> +void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb)
> +{
> + struct hlist_nulls_head *nhead;
> + struct sockaddr_storage ss;
> + const u8 *local_ip = NULL;
> + struct sockaddr_in6 *sa6;
> + struct sockaddr_in *sa;
> + struct ovpn_bind *bind;
> + size_t salen = 0;
> +
> + spin_lock_bh(&peer->lock);
> + bind = rcu_dereference_protected(peer->bind,
> + lockdep_is_held(&peer->lock));
> + if (unlikely(!bind))
> + goto unlock;
> +
> + switch (skb->protocol) {
> + case htons(ETH_P_IP):
> + /* float check */
> + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) {
> + if (bind->remote.in4.sin_family == AF_INET)
> + local_ip = (u8 *)&bind->local;
If I'm reading this correctly, we always reuse the existing local
address when we have to re-create the bind, even if it doesn't match
the skb? The "local endpoint update" chunk below is doing that, but
only if we're keeping the same remote? It'll get updated the next time
we receive a packet and call ovpn_peer_endpoints_update.
That might irritate the RPF check on the other side, if we still use
our "old" source to talk to the new dest?
> + sa = (struct sockaddr_in *)&ss;
> + sa->sin_family = AF_INET;
> + sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
> + sa->sin_port = udp_hdr(skb)->source;
> + salen = sizeof(*sa);
> + break;
> + }
> +
> + /* local endpoint update */
> + if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) {
> + net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n",
> + netdev_name(peer->ovpn->dev),
> + peer->id, &bind->local.ipv4.s_addr,
> + &ip_hdr(skb)->daddr);
> + bind->local.ipv4.s_addr = ip_hdr(skb)->daddr;
> + }
> + break;
[...]
> + if (peer->ovpn->mode == OVPN_MODE_MP) {
> + spin_lock_bh(&peer->ovpn->lock);
> + spin_lock_bh(&peer->lock);
> + bind = rcu_dereference_protected(peer->bind,
> + lockdep_is_held(&peer->lock));
> + if (unlikely(!bind)) {
> + spin_unlock_bh(&peer->lock);
> + spin_unlock_bh(&peer->ovpn->lock);
> + return;
> + }
> +
> + /* his function may be invoked concurrently, therefore another
typo:
^ This
[...]
> -/* variable name __tbl2 needs to be different from __tbl1
> - * in the macro below to avoid confusing clang
> - */
> -#define ovpn_get_hash_slot(_tbl, _key, _key_len) ({ \
> - typeof(_tbl) *__tbl2 = &(_tbl); \
> - jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl2); \
> -})
> -
> -#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \
> - typeof(_tbl) *__tbl1 = &(_tbl); \
> - &(*__tbl1)[ovpn_get_hash_slot(*__tbl1, _key, _key_len)];\
> -})
> -
> /**
> * ovpn_peer_get_by_vpn_addr4 - retrieve peer by its VPN IPv4 address
> * @ovpn: the openvpn instance to search
> @@ -522,51 +694,6 @@ static void ovpn_peer_remove(struct ovpn_peer *peer,
> llist_add(&peer->release_entry, release_list);
> }
>
> -/**
> - * ovpn_peer_update_local_endpoint - update local endpoint for peer
> - * @peer: peer to update the endpoint for
> - * @skb: incoming packet to retrieve the destination address (local) from
> - */
> -void ovpn_peer_update_local_endpoint(struct ovpn_peer *peer,
> - struct sk_buff *skb)
> -{
> - struct ovpn_bind *bind;
> -
> - rcu_read_lock();
> - bind = rcu_dereference(peer->bind);
> - if (unlikely(!bind))
> - goto unlock;
> -
> - spin_lock_bh(&peer->lock);
> - switch (skb->protocol) {
> - case htons(ETH_P_IP):
> - if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) {
> - net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n",
> - netdev_name(peer->ovpn->dev),
> - peer->id, &bind->local.ipv4.s_addr,
> - &ip_hdr(skb)->daddr);
> - bind->local.ipv4.s_addr = ip_hdr(skb)->daddr;
> - }
> - break;
> - case htons(ETH_P_IPV6):
> - if (unlikely(!ipv6_addr_equal(&bind->local.ipv6,
> - &ipv6_hdr(skb)->daddr))) {
> - net_dbg_ratelimited("%s: learning local IPv6 for peer %d (%pI6c -> %pI6c\n",
> - netdev_name(peer->ovpn->dev),
> - peer->id, &bind->local.ipv6,
> - &ipv6_hdr(skb)->daddr);
> - bind->local.ipv6 = ipv6_hdr(skb)->daddr;
> - }
> - break;
> - default:
> - break;
> - }
> - spin_unlock_bh(&peer->lock);
> -
> -unlock:
> - rcu_read_unlock();
> -}
I guess you could squash this and the previous patch into one to
reduce the churn (and get a little bit closer to the 15-patch limit :))
--
Sabrina
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 18/24] ovpn: add support for peer floating
2025-03-04 18:37 ` Sabrina Dubroca
@ 2025-03-04 23:19 ` Antonio Quartulli
2025-03-05 0:19 ` Antonio Quartulli
2025-03-05 11:20 ` Sabrina Dubroca
0 siblings, 2 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 23:19 UTC (permalink / raw)
To: Sabrina Dubroca
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
On 04/03/2025 19:37, Sabrina Dubroca wrote:
> 2025-03-04, 01:33:48 +0100, Antonio Quartulli wrote:
>> A peer connected via UDP may change its IP address without reconnecting
>> (float).
>
> Should that trigger a reset of the peer->dst_cache? And same when
> userspace updates the remote address? Otherwise it seems we could be
> stuck with a cached dst that cannot reach the peer.
Yeah, that make sense, otherwise ovpn_udpX_output would just try over
and over to re-use the cached source address (unless it becomes
unavailable).
>
>
>> +void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb)
>> +{
>> + struct hlist_nulls_head *nhead;
>> + struct sockaddr_storage ss;
>> + const u8 *local_ip = NULL;
>> + struct sockaddr_in6 *sa6;
>> + struct sockaddr_in *sa;
>> + struct ovpn_bind *bind;
>> + size_t salen = 0;
>> +
>> + spin_lock_bh(&peer->lock);
>> + bind = rcu_dereference_protected(peer->bind,
>> + lockdep_is_held(&peer->lock));
>> + if (unlikely(!bind))
>> + goto unlock;
>> +
>> + switch (skb->protocol) {
>> + case htons(ETH_P_IP):
>> + /* float check */
>> + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) {
>> + if (bind->remote.in4.sin_family == AF_INET)
>> + local_ip = (u8 *)&bind->local;
>
> If I'm reading this correctly, we always reuse the existing local
> address when we have to re-create the bind, even if it doesn't match
> the skb? The "local endpoint update" chunk below is doing that, but
> only if we're keeping the same remote? It'll get updated the next time
> we receive a packet and call ovpn_peer_endpoints_update.
>
> That might irritate the RPF check on the other side, if we still use
> our "old" source to talk to the new dest?
>
>> + sa = (struct sockaddr_in *)&ss;
>> + sa->sin_family = AF_INET;
>> + sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
>> + sa->sin_port = udp_hdr(skb)->source;
>> + salen = sizeof(*sa);
>> + break;
I think the issue is simply this 'break' above - by removing it,
everything should work as expected.
I thin this is a leftover from when float check and endpoint update were
two different functions/switch blocks.
>> + }
>> +
>> + /* local endpoint update */
>> + if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) {
>> + net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n",
>> + netdev_name(peer->ovpn->dev),
>> + peer->id, &bind->local.ipv4.s_addr,
>> + &ip_hdr(skb)->daddr);
>> + bind->local.ipv4.s_addr = ip_hdr(skb)->daddr;
>> + }
>> + break;
>
> [...]
>> + if (peer->ovpn->mode == OVPN_MODE_MP) {
>> + spin_lock_bh(&peer->ovpn->lock);
>> + spin_lock_bh(&peer->lock);
>> + bind = rcu_dereference_protected(peer->bind,
>> + lockdep_is_held(&peer->lock));
>> + if (unlikely(!bind)) {
>> + spin_unlock_bh(&peer->lock);
>> + spin_unlock_bh(&peer->ovpn->lock);
>> + return;
>> + }
>> +
>> + /* his function may be invoked concurrently, therefore another
>
> typo:
> ^ This
ACK
>
>
> [...]
>> -/* variable name __tbl2 needs to be different from __tbl1
>> - * in the macro below to avoid confusing clang
>> - */
>> -#define ovpn_get_hash_slot(_tbl, _key, _key_len) ({ \
>> - typeof(_tbl) *__tbl2 = &(_tbl); \
>> - jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl2); \
>> -})
>> -
>> -#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \
>> - typeof(_tbl) *__tbl1 = &(_tbl); \
>> - &(*__tbl1)[ovpn_get_hash_slot(*__tbl1, _key, _key_len)];\
>> -})
>> -
>> /**
>> * ovpn_peer_get_by_vpn_addr4 - retrieve peer by its VPN IPv4 address
>> * @ovpn: the openvpn instance to search
>> @@ -522,51 +694,6 @@ static void ovpn_peer_remove(struct ovpn_peer *peer,
>> llist_add(&peer->release_entry, release_list);
>> }
>>
>> -/**
>> - * ovpn_peer_update_local_endpoint - update local endpoint for peer
>> - * @peer: peer to update the endpoint for
>> - * @skb: incoming packet to retrieve the destination address (local) from
>> - */
>> -void ovpn_peer_update_local_endpoint(struct ovpn_peer *peer,
>> - struct sk_buff *skb)
>> -{
>> - struct ovpn_bind *bind;
>> -
>> - rcu_read_lock();
>> - bind = rcu_dereference(peer->bind);
>> - if (unlikely(!bind))
>> - goto unlock;
>> -
>> - spin_lock_bh(&peer->lock);
>> - switch (skb->protocol) {
>> - case htons(ETH_P_IP):
>> - if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) {
>> - net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n",
>> - netdev_name(peer->ovpn->dev),
>> - peer->id, &bind->local.ipv4.s_addr,
>> - &ip_hdr(skb)->daddr);
>> - bind->local.ipv4.s_addr = ip_hdr(skb)->daddr;
>> - }
>> - break;
>> - case htons(ETH_P_IPV6):
>> - if (unlikely(!ipv6_addr_equal(&bind->local.ipv6,
>> - &ipv6_hdr(skb)->daddr))) {
>> - net_dbg_ratelimited("%s: learning local IPv6 for peer %d (%pI6c -> %pI6c\n",
>> - netdev_name(peer->ovpn->dev),
>> - peer->id, &bind->local.ipv6,
>> - &ipv6_hdr(skb)->daddr);
>> - bind->local.ipv6 = ipv6_hdr(skb)->daddr;
>> - }
>> - break;
>> - default:
>> - break;
>> - }
>> - spin_unlock_bh(&peer->lock);
>> -
>> -unlock:
>> - rcu_read_unlock();
>> -}
>
> I guess you could squash this and the previous patch into one to
> reduce the churn (and get a little bit closer to the 15-patch limit :))
Hehe I can see you're getting familiar with the code :-)
Will do!
Thanks!
>
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 18/24] ovpn: add support for peer floating
2025-03-04 23:19 ` Antonio Quartulli
@ 2025-03-05 0:19 ` Antonio Quartulli
2025-03-05 11:20 ` Sabrina Dubroca
1 sibling, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-05 0:19 UTC (permalink / raw)
To: Sabrina Dubroca
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
On 05/03/2025 00:19, Antonio Quartulli wrote:
> On 04/03/2025 19:37, Sabrina Dubroca wrote:
>> 2025-03-04, 01:33:48 +0100, Antonio Quartulli wrote:
>>> A peer connected via UDP may change its IP address without reconnecting
>>> (float).
>>
>> Should that trigger a reset of the peer->dst_cache? And same when
>> userspace updates the remote address? Otherwise it seems we could be
>> stuck with a cached dst that cannot reach the peer.
>
> Yeah, that make sense, otherwise ovpn_udpX_output would just try over
> and over to re-use the cached source address (unless it becomes
> unavailable).
I spent some more time thinking about this.
It makes sense to reset the dst cache when the local address changes,
but not in case of float (remote address changed).
That's because we always want to first attempt sending packets using the
address where the remote peer sent the traffic to.
Should that not work (quite rare), then we have code in ovpn_udpX_output
that will reset the cache and attempt a different address.
Cheers,
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 46+ messages in thread
* Re: [PATCH v21 18/24] ovpn: add support for peer floating
2025-03-04 23:19 ` Antonio Quartulli
2025-03-05 0:19 ` Antonio Quartulli
@ 2025-03-05 11:20 ` Sabrina Dubroca
2025-03-05 13:14 ` Antonio Quartulli
1 sibling, 1 reply; 46+ messages in thread
From: Sabrina Dubroca @ 2025-03-05 11:20 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
2025-03-05, 00:19:32 +0100, Antonio Quartulli wrote:
> On 04/03/2025 19:37, Sabrina Dubroca wrote:
> > 2025-03-04, 01:33:48 +0100, Antonio Quartulli wrote:
> > > A peer connected via UDP may change its IP address without reconnecting
> > > (float).
> >
> > Should that trigger a reset of the peer->dst_cache? And same when
> > userspace updates the remote address? Otherwise it seems we could be
> > stuck with a cached dst that cannot reach the peer.
>
> Yeah, that make sense, otherwise ovpn_udpX_output would just try over and
> over to re-use the cached source address (unless it becomes unavailable).
Not just the source address, the routing entry too. I'm more concerned
about that: trying to reuse a a cached routing entry that was good for
the previous remote address, but not for the new one.
[adding your next email]
> I spent some more time thinking about this.
> It makes sense to reset the dst cache when the local address changes, but
> not in case of float (remote address changed).
>
> That's because we always want to first attempt sending packets using the
> address where the remote peer sent the traffic to.
> Should that not work (quite rare), then we have code in ovpn_udpX_output
> that will reset the cache and attempt a different address.
I don't think the code in ovpn_udpX_output will reset the cache unless
it was made invalid by a system-wide routing table update (see
dst_cache_per_cpu_get).
rt = dst_cache_get_ip4(cache, &fl.saddr);
if (rt)
goto transmit;
...
transmit:
udp_tunnel_xmit_skb(rt, sk, skb, fl.saddr, fl.daddr, 0,
ip4_dst_hoplimit(&rt->dst), 0, fl.fl4_sport,
fl.fl4_dport, false, sk->sk_no_check_tx);
So it seems that as long as dst_cache_get_ip4 gets us a dst (which
AFAIU will happen, unless we did a dst_cache_reset or something else
made the cached dst invalid -- and ovpn's floating/endpoint update
doesn't do that), we'll just use it.
> > > +void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb)
> > > +{
> > > + struct hlist_nulls_head *nhead;
> > > + struct sockaddr_storage ss;
> > > + const u8 *local_ip = NULL;
> > > + struct sockaddr_in6 *sa6;
> > > + struct sockaddr_in *sa;
> > > + struct ovpn_bind *bind;
> > > + size_t salen = 0;
> > > +
> > > + spin_lock_bh(&peer->lock);
> > > + bind = rcu_dereference_protected(peer->bind,
> > > + lockdep_is_held(&peer->lock));
> > > + if (unlikely(!bind))
> > > + goto unlock;
> > > +
> > > + switch (skb->protocol) {
> > > + case htons(ETH_P_IP):
> > > + /* float check */
> > > + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) {
> > > + if (bind->remote.in4.sin_family == AF_INET)
> > > + local_ip = (u8 *)&bind->local;
> >
> > If I'm reading this correctly, we always reuse the existing local
> > address when we have to re-create the bind, even if it doesn't match
> > the skb? The "local endpoint update" chunk below is doing that, but
> > only if we're keeping the same remote? It'll get updated the next time
> > we receive a packet and call ovpn_peer_endpoints_update.
> >
> > That might irritate the RPF check on the other side, if we still use
> > our "old" source to talk to the new dest?
> >
> > > + sa = (struct sockaddr_in *)&ss;
> > > + sa->sin_family = AF_INET;
> > > + sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
> > > + sa->sin_port = udp_hdr(skb)->source;
> > > + salen = sizeof(*sa);
> > > + break;
>
> I think the issue is simply this 'break' above - by removing it, everything
> should work as expected.
Only if the bind was of the correct family? Checking an IPv4 local
address (in the bind) against an IPv6 source address in the packet (or
the other way around) isn't going to work well.
> I thin this is a leftover from when float check and endpoint update were two
> different functions/switch blocks.
>
> > > + }
> > > +
> > > + /* local endpoint update */
> > > + if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) {
> > > + net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n",
> > > + netdev_name(peer->ovpn->dev),
> > > + peer->id, &bind->local.ipv4.s_addr,
> > > + &ip_hdr(skb)->daddr);
> > > + bind->local.ipv4.s_addr = ip_hdr(skb)->daddr;
> > > + }
> > > + break;
--
Sabrina
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 18/24] ovpn: add support for peer floating
2025-03-05 11:20 ` Sabrina Dubroca
@ 2025-03-05 13:14 ` Antonio Quartulli
2025-03-05 16:56 ` Sabrina Dubroca
0 siblings, 1 reply; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-05 13:14 UTC (permalink / raw)
To: Sabrina Dubroca
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
On 05/03/2025 12:20, Sabrina Dubroca wrote:
> 2025-03-05, 00:19:32 +0100, Antonio Quartulli wrote:
>> On 04/03/2025 19:37, Sabrina Dubroca wrote:
>>> 2025-03-04, 01:33:48 +0100, Antonio Quartulli wrote:
>>>> A peer connected via UDP may change its IP address without reconnecting
>>>> (float).
>>>
>>> Should that trigger a reset of the peer->dst_cache? And same when
>>> userspace updates the remote address? Otherwise it seems we could be
>>> stuck with a cached dst that cannot reach the peer.
>>
>> Yeah, that make sense, otherwise ovpn_udpX_output would just try over and
>> over to re-use the cached source address (unless it becomes unavailable).
>
> Not just the source address, the routing entry too. I'm more concerned
> about that: trying to reuse a a cached routing entry that was good for
> the previous remote address, but not for the new one.
>
>
> [adding your next email]
>> I spent some more time thinking about this.
>> It makes sense to reset the dst cache when the local address changes, but
>> not in case of float (remote address changed).
>>
>> That's because we always want to first attempt sending packets using the
>> address where the remote peer sent the traffic to.
>> Should that not work (quite rare), then we have code in ovpn_udpX_output
>> that will reset the cache and attempt a different address.
>
> I don't think the code in ovpn_udpX_output will reset the cache unless
> it was made invalid by a system-wide routing table update (see
> dst_cache_per_cpu_get).
>
> rt = dst_cache_get_ip4(cache, &fl.saddr);
> if (rt)
> goto transmit;
> ...
> transmit:
> udp_tunnel_xmit_skb(rt, sk, skb, fl.saddr, fl.daddr, 0,
> ip4_dst_hoplimit(&rt->dst), 0, fl.fl4_sport,
> fl.fl4_dport, false, sk->sk_no_check_tx);
>
>
> So it seems that as long as dst_cache_get_ip4 gets us a dst (which
> AFAIU will happen, unless we did a dst_cache_reset or something else
> made the cached dst invalid -- and ovpn's floating/endpoint update
> doesn't do that), we'll just use it.
Mh yeah, you're right.
Then I'll reset the cache also when a float is detected.
>
>
>>>> +void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb)
>>>> +{
>>>> + struct hlist_nulls_head *nhead;
>>>> + struct sockaddr_storage ss;
>>>> + const u8 *local_ip = NULL;
>>>> + struct sockaddr_in6 *sa6;
>>>> + struct sockaddr_in *sa;
>>>> + struct ovpn_bind *bind;
>>>> + size_t salen = 0;
>>>> +
>>>> + spin_lock_bh(&peer->lock);
>>>> + bind = rcu_dereference_protected(peer->bind,
>>>> + lockdep_is_held(&peer->lock));
>>>> + if (unlikely(!bind))
>>>> + goto unlock;
>>>> +
>>>> + switch (skb->protocol) {
>>>> + case htons(ETH_P_IP):
>>>> + /* float check */
>>>> + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) {
>>>> + if (bind->remote.in4.sin_family == AF_INET)
>>>> + local_ip = (u8 *)&bind->local;
>>>
>>> If I'm reading this correctly, we always reuse the existing local
>>> address when we have to re-create the bind, even if it doesn't match
>>> the skb? The "local endpoint update" chunk below is doing that, but
>>> only if we're keeping the same remote? It'll get updated the next time
>>> we receive a packet and call ovpn_peer_endpoints_update.
>>>
>>> That might irritate the RPF check on the other side, if we still use
>>> our "old" source to talk to the new dest?
>>>
>>>> + sa = (struct sockaddr_in *)&ss;
>>>> + sa->sin_family = AF_INET;
>>>> + sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
>>>> + sa->sin_port = udp_hdr(skb)->source;
>>>> + salen = sizeof(*sa);
>>>> + break;
>>
>> I think the issue is simply this 'break' above - by removing it, everything
>> should work as expected.
>
> Only if the bind was of the correct family? Checking an IPv4 local
> address (in the bind) against an IPv6 source address in the packet (or
> the other way around) isn't going to work well.
Ah I understand what you mean.
The purpose of "local_ip" is to provide a working local endpoint to be
used with the new remote address.
However, if the float is switching family we can't re-use the same old
local endpoint (hence the check).
In this case we'll learn the "new" local address later.
Does it make sense?
Cheers,
>
>
>> I thin this is a leftover from when float check and endpoint update were two
>> different functions/switch blocks.
>>
>>>> + }
>>>> +
>>>> + /* local endpoint update */
>>>> + if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) {
>>>> + net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n",
>>>> + netdev_name(peer->ovpn->dev),
>>>> + peer->id, &bind->local.ipv4.s_addr,
>>>> + &ip_hdr(skb)->daddr);
>>>> + bind->local.ipv4.s_addr = ip_hdr(skb)->daddr;
>>>> + }
>>>> + break;
>
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 18/24] ovpn: add support for peer floating
2025-03-05 13:14 ` Antonio Quartulli
@ 2025-03-05 16:56 ` Sabrina Dubroca
2025-03-06 10:02 ` Antonio Quartulli
0 siblings, 1 reply; 46+ messages in thread
From: Sabrina Dubroca @ 2025-03-05 16:56 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
2025-03-05, 14:14:36 +0100, Antonio Quartulli wrote:
> On 05/03/2025 12:20, Sabrina Dubroca wrote:
> > 2025-03-05, 00:19:32 +0100, Antonio Quartulli wrote:
> > > On 04/03/2025 19:37, Sabrina Dubroca wrote:
> > > > 2025-03-04, 01:33:48 +0100, Antonio Quartulli wrote:
> > > > > A peer connected via UDP may change its IP address without reconnecting
> > > > > (float).
> > > >
> > > > Should that trigger a reset of the peer->dst_cache? And same when
> > > > userspace updates the remote address? Otherwise it seems we could be
> > > > stuck with a cached dst that cannot reach the peer.
> > >
> > > Yeah, that make sense, otherwise ovpn_udpX_output would just try over and
> > > over to re-use the cached source address (unless it becomes unavailable).
> >
> > Not just the source address, the routing entry too. I'm more concerned
> > about that: trying to reuse a a cached routing entry that was good for
> > the previous remote address, but not for the new one.
> >
> >
> > [adding your next email]
> > > I spent some more time thinking about this.
> > > It makes sense to reset the dst cache when the local address changes, but
> > > not in case of float (remote address changed).
> > >
> > > That's because we always want to first attempt sending packets using the
> > > address where the remote peer sent the traffic to.
> > > Should that not work (quite rare), then we have code in ovpn_udpX_output
> > > that will reset the cache and attempt a different address.
> >
> > I don't think the code in ovpn_udpX_output will reset the cache unless
> > it was made invalid by a system-wide routing table update (see
> > dst_cache_per_cpu_get).
> >
> > rt = dst_cache_get_ip4(cache, &fl.saddr);
> > if (rt)
> > goto transmit;
> > ...
> > transmit:
> > udp_tunnel_xmit_skb(rt, sk, skb, fl.saddr, fl.daddr, 0,
> > ip4_dst_hoplimit(&rt->dst), 0, fl.fl4_sport,
> > fl.fl4_dport, false, sk->sk_no_check_tx);
> >
> >
> > So it seems that as long as dst_cache_get_ip4 gets us a dst (which
> > AFAIU will happen, unless we did a dst_cache_reset or something else
> > made the cached dst invalid -- and ovpn's floating/endpoint update
> > doesn't do that), we'll just use it.
>
> Mh yeah, you're right.
> Then I'll reset the cache also when a float is detected.
Ok, thanks.
> >
> >
> > > > > +void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb)
> > > > > +{
> > > > > + struct hlist_nulls_head *nhead;
> > > > > + struct sockaddr_storage ss;
> > > > > + const u8 *local_ip = NULL;
> > > > > + struct sockaddr_in6 *sa6;
> > > > > + struct sockaddr_in *sa;
> > > > > + struct ovpn_bind *bind;
> > > > > + size_t salen = 0;
> > > > > +
> > > > > + spin_lock_bh(&peer->lock);
> > > > > + bind = rcu_dereference_protected(peer->bind,
> > > > > + lockdep_is_held(&peer->lock));
> > > > > + if (unlikely(!bind))
> > > > > + goto unlock;
> > > > > +
> > > > > + switch (skb->protocol) {
> > > > > + case htons(ETH_P_IP):
> > > > > + /* float check */
> > > > > + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) {
> > > > > + if (bind->remote.in4.sin_family == AF_INET)
> > > > > + local_ip = (u8 *)&bind->local;
> > > >
> > > > If I'm reading this correctly, we always reuse the existing local
> > > > address when we have to re-create the bind, even if it doesn't match
> > > > the skb? The "local endpoint update" chunk below is doing that, but
> > > > only if we're keeping the same remote? It'll get updated the next time
> > > > we receive a packet and call ovpn_peer_endpoints_update.
> > > >
> > > > That might irritate the RPF check on the other side, if we still use
> > > > our "old" source to talk to the new dest?
> > > >
> > > > > + sa = (struct sockaddr_in *)&ss;
> > > > > + sa->sin_family = AF_INET;
> > > > > + sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
> > > > > + sa->sin_port = udp_hdr(skb)->source;
> > > > > + salen = sizeof(*sa);
> > > > > + break;
> > >
> > > I think the issue is simply this 'break' above - by removing it, everything
> > > should work as expected.
> >
> > Only if the bind was of the correct family? Checking an IPv4 local
> > address (in the bind) against an IPv6 source address in the packet (or
> > the other way around) isn't going to work well.
>
> Ah I understand what you mean.
>
> The purpose of "local_ip" is to provide a working local endpoint to be used
> with the new remote address.
> However, if the float is switching family we can't re-use the same old local
> endpoint (hence the check).
> In this case we'll learn the "new" local address later.
>
> Does it make sense?
Sure, but we could have learned it immediately from the packet we just
got, whether we're changing family or not. No need to wait for the
next RX packet to also learn the new local address.
But if we now do a dst_cache_reset with the peer float,
ovpn_udp*_output will have to do a new route/local address lookup and
I guess that should clean up the local address stored in the bind, and
then update the dst_cache with the local address we just found.
--
Sabrina
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 18/24] ovpn: add support for peer floating
2025-03-05 16:56 ` Sabrina Dubroca
@ 2025-03-06 10:02 ` Antonio Quartulli
2025-03-07 10:12 ` Sabrina Dubroca
0 siblings, 1 reply; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-06 10:02 UTC (permalink / raw)
To: Sabrina Dubroca
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
On 05/03/2025 17:56, Sabrina Dubroca wrote:
> 2025-03-05, 14:14:36 +0100, Antonio Quartulli wrote:
>> On 05/03/2025 12:20, Sabrina Dubroca wrote:
>>> 2025-03-05, 00:19:32 +0100, Antonio Quartulli wrote:
>>>> On 04/03/2025 19:37, Sabrina Dubroca wrote:
>>>>> 2025-03-04, 01:33:48 +0100, Antonio Quartulli wrote:
>>>>>> A peer connected via UDP may change its IP address without reconnecting
>>>>>> (float).
>>>>>
>>>>> Should that trigger a reset of the peer->dst_cache? And same when
>>>>> userspace updates the remote address? Otherwise it seems we could be
>>>>> stuck with a cached dst that cannot reach the peer.
>>>>
>>>> Yeah, that make sense, otherwise ovpn_udpX_output would just try over and
>>>> over to re-use the cached source address (unless it becomes unavailable).
>>>
>>> Not just the source address, the routing entry too. I'm more concerned
>>> about that: trying to reuse a a cached routing entry that was good for
>>> the previous remote address, but not for the new one.
>>>
>>>
>>> [adding your next email]
>>>> I spent some more time thinking about this.
>>>> It makes sense to reset the dst cache when the local address changes, but
>>>> not in case of float (remote address changed).
>>>>
>>>> That's because we always want to first attempt sending packets using the
>>>> address where the remote peer sent the traffic to.
>>>> Should that not work (quite rare), then we have code in ovpn_udpX_output
>>>> that will reset the cache and attempt a different address.
>>>
>>> I don't think the code in ovpn_udpX_output will reset the cache unless
>>> it was made invalid by a system-wide routing table update (see
>>> dst_cache_per_cpu_get).
>>>
>>> rt = dst_cache_get_ip4(cache, &fl.saddr);
>>> if (rt)
>>> goto transmit;
>>> ...
>>> transmit:
>>> udp_tunnel_xmit_skb(rt, sk, skb, fl.saddr, fl.daddr, 0,
>>> ip4_dst_hoplimit(&rt->dst), 0, fl.fl4_sport,
>>> fl.fl4_dport, false, sk->sk_no_check_tx);
>>>
>>>
>>> So it seems that as long as dst_cache_get_ip4 gets us a dst (which
>>> AFAIU will happen, unless we did a dst_cache_reset or something else
>>> made the cached dst invalid -- and ovpn's floating/endpoint update
>>> doesn't do that), we'll just use it.
>>
>> Mh yeah, you're right.
>> Then I'll reset the cache also when a float is detected.
>
> Ok, thanks.
>
>>>
>>>
>>>>>> +void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb)
>>>>>> +{
>>>>>> + struct hlist_nulls_head *nhead;
>>>>>> + struct sockaddr_storage ss;
>>>>>> + const u8 *local_ip = NULL;
>>>>>> + struct sockaddr_in6 *sa6;
>>>>>> + struct sockaddr_in *sa;
>>>>>> + struct ovpn_bind *bind;
>>>>>> + size_t salen = 0;
>>>>>> +
>>>>>> + spin_lock_bh(&peer->lock);
>>>>>> + bind = rcu_dereference_protected(peer->bind,
>>>>>> + lockdep_is_held(&peer->lock));
>>>>>> + if (unlikely(!bind))
>>>>>> + goto unlock;
>>>>>> +
>>>>>> + switch (skb->protocol) {
>>>>>> + case htons(ETH_P_IP):
>>>>>> + /* float check */
>>>>>> + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) {
>>>>>> + if (bind->remote.in4.sin_family == AF_INET)
>>>>>> + local_ip = (u8 *)&bind->local;
>>>>>
>>>>> If I'm reading this correctly, we always reuse the existing local
>>>>> address when we have to re-create the bind, even if it doesn't match
>>>>> the skb? The "local endpoint update" chunk below is doing that, but
>>>>> only if we're keeping the same remote? It'll get updated the next time
>>>>> we receive a packet and call ovpn_peer_endpoints_update.
>>>>>
>>>>> That might irritate the RPF check on the other side, if we still use
>>>>> our "old" source to talk to the new dest?
>>>>>
>>>>>> + sa = (struct sockaddr_in *)&ss;
>>>>>> + sa->sin_family = AF_INET;
>>>>>> + sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
>>>>>> + sa->sin_port = udp_hdr(skb)->source;
>>>>>> + salen = sizeof(*sa);
>>>>>> + break;
>>>>
>>>> I think the issue is simply this 'break' above - by removing it, everything
>>>> should work as expected.
>>>
>>> Only if the bind was of the correct family? Checking an IPv4 local
>>> address (in the bind) against an IPv6 source address in the packet (or
>>> the other way around) isn't going to work well.
>>
>> Ah I understand what you mean.
>>
>> The purpose of "local_ip" is to provide a working local endpoint to be used
>> with the new remote address.
>> However, if the float is switching family we can't re-use the same old local
>> endpoint (hence the check).
>> In this case we'll learn the "new" local address later.
>>
>> Does it make sense?
>
> Sure, but we could have learned it immediately from the packet we just
> got, whether we're changing family or not. No need to wait for the
> next RX packet to also learn the new local address.
Indeed.
>
> But if we now do a dst_cache_reset with the peer float,
> ovpn_udp*_output will have to do a new route/local address lookup and
> I guess that should clean up the local address stored in the bind, and
> then update the dst_cache with the local address we just found.
Right and this may not truly be what we want.
If peer X is sending packets to our IP1, we should at least try to reply
from the same address.
If we have two IPs, IP1 and IP2, and both can be used to reach peer X,
we should always try to use the one where we received traffic from X in
the first place.
OTOH hand it is also true that with floating detection on both sides,
the situation will converge quickly, but there might be a reason why X
chose IP1 as destination, therefore we should do our best to respect that.
So, even in case of float, we should still store the local endpoint and
attempt fetching a route that takes that into consideration.
Which I think is what is happening (assuming we reset the dst_cache on
float).
ovpn_udpX_output() will:
* get no rt from the cache
* possibly confirm that saddr is ok
* fetch the new rt using the provided saddr and daddr
* update the cache.
That makes sense to me.
Would you agree?
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 18/24] ovpn: add support for peer floating
2025-03-06 10:02 ` Antonio Quartulli
@ 2025-03-07 10:12 ` Sabrina Dubroca
2025-03-10 12:57 ` Antonio Quartulli
0 siblings, 1 reply; 46+ messages in thread
From: Sabrina Dubroca @ 2025-03-07 10:12 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
2025-03-06, 11:02:50 +0100, Antonio Quartulli wrote:
> On 05/03/2025 17:56, Sabrina Dubroca wrote:
> > 2025-03-05, 14:14:36 +0100, Antonio Quartulli wrote:
> > > On 05/03/2025 12:20, Sabrina Dubroca wrote:
> > > > 2025-03-05, 00:19:32 +0100, Antonio Quartulli wrote:
> > > > > On 04/03/2025 19:37, Sabrina Dubroca wrote:
> > > > > > 2025-03-04, 01:33:48 +0100, Antonio Quartulli wrote:
> > > > > > > +void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb)
> > > > > > > +{
> > > > > > > + struct hlist_nulls_head *nhead;
> > > > > > > + struct sockaddr_storage ss;
> > > > > > > + const u8 *local_ip = NULL;
> > > > > > > + struct sockaddr_in6 *sa6;
> > > > > > > + struct sockaddr_in *sa;
> > > > > > > + struct ovpn_bind *bind;
> > > > > > > + size_t salen = 0;
> > > > > > > +
> > > > > > > + spin_lock_bh(&peer->lock);
> > > > > > > + bind = rcu_dereference_protected(peer->bind,
> > > > > > > + lockdep_is_held(&peer->lock));
> > > > > > > + if (unlikely(!bind))
> > > > > > > + goto unlock;
> > > > > > > +
> > > > > > > + switch (skb->protocol) {
> > > > > > > + case htons(ETH_P_IP):
> > > > > > > + /* float check */
> > > > > > > + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) {
> > > > > > > + if (bind->remote.in4.sin_family == AF_INET)
> > > > > > > + local_ip = (u8 *)&bind->local;
> > > > > >
> > > > > > If I'm reading this correctly, we always reuse the existing local
> > > > > > address when we have to re-create the bind, even if it doesn't match
> > > > > > the skb? The "local endpoint update" chunk below is doing that, but
> > > > > > only if we're keeping the same remote? It'll get updated the next time
> > > > > > we receive a packet and call ovpn_peer_endpoints_update.
> > > > > >
> > > > > > That might irritate the RPF check on the other side, if we still use
> > > > > > our "old" source to talk to the new dest?
> > > > > >
> > > > > > > + sa = (struct sockaddr_in *)&ss;
> > > > > > > + sa->sin_family = AF_INET;
> > > > > > > + sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
> > > > > > > + sa->sin_port = udp_hdr(skb)->source;
> > > > > > > + salen = sizeof(*sa);
> > > > > > > + break;
> > > > >
> > > > > I think the issue is simply this 'break' above - by removing it, everything
> > > > > should work as expected.
> > > >
> > > > Only if the bind was of the correct family? Checking an IPv4 local
> > > > address (in the bind) against an IPv6 source address in the packet (or
> > > > the other way around) isn't going to work well.
> > >
> > > Ah I understand what you mean.
> > >
> > > The purpose of "local_ip" is to provide a working local endpoint to be used
> > > with the new remote address.
> > > However, if the float is switching family we can't re-use the same old local
> > > endpoint (hence the check).
> > > In this case we'll learn the "new" local address later.
> > >
> > > Does it make sense?
> >
> > Sure, but we could have learned it immediately from the packet we just
> > got, whether we're changing family or not. No need to wait for the
> > next RX packet to also learn the new local address.
>
> Indeed.
>
> >
> > But if we now do a dst_cache_reset with the peer float,
> > ovpn_udp*_output will have to do a new route/local address lookup and
> > I guess that should clean up the local address stored in the bind, and
> > then update the dst_cache with the local address we just found.
>
> Right and this may not truly be what we want.
>
> If peer X is sending packets to our IP1, we should at least try to reply
> from the same address.
>
> If we have two IPs, IP1 and IP2, and both can be used to reach peer X, we
> should always try to use the one where we received traffic from X in the
> first place.
I had a thought that it might not be our prefered address to talk to
X, but it would probably be, since we decided to use it (and thus X
used it as remote to talk to us).
> OTOH hand it is also true that with floating detection on both sides, the
> situation will converge quickly, but there might be a reason why X chose IP1
> as destination, therefore we should do our best to respect that.
And I guess the primary reason for X to choose IP1 would be "we sent
packets to X from IP1".
> So, even in case of float, we should still store the local endpoint and
> attempt fetching a route that takes that into consideration.
> Which I think is what is happening (assuming we reset the dst_cache on
> float).
Not at the same time as float, unless ovpn_peer_endpoints_update sets
local_ip = ip_hdr(skb)->daddr unconditionally on float?
Otherwise the next route lookup in ovpn_udpX_output will pick whatever
source address it wants (which would likely match what's in the
received skb during float, so probably fine anyway).
> ovpn_udpX_output() will:
> * get no rt from the cache
> * possibly confirm that saddr is ok
> * fetch the new rt using the provided saddr and daddr
> * update the cache.
>
> That makes sense to me.
> Would you agree?
With dst_cache reset on float, yes. As long as we have that, the main
behavior seems correct to me. (maybe some corner cases will not be
handled optimally, but that can be improved later - which is most
likely what I've been discussing in these emails :))
[this could be a useful counter to add in the future: number of floats
and local address updates - so the user can check if that's increasing
"too often", which would indicate something weird is happening]
--
Sabrina
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 18/24] ovpn: add support for peer floating
2025-03-07 10:12 ` Sabrina Dubroca
@ 2025-03-10 12:57 ` Antonio Quartulli
2025-03-10 22:32 ` Sabrina Dubroca
0 siblings, 1 reply; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-10 12:57 UTC (permalink / raw)
To: Sabrina Dubroca
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
On 07/03/2025 11:12, Sabrina Dubroca wrote:
> 2025-03-06, 11:02:50 +0100, Antonio Quartulli wrote:
>> On 05/03/2025 17:56, Sabrina Dubroca wrote:
>>> 2025-03-05, 14:14:36 +0100, Antonio Quartulli wrote:
>>>> On 05/03/2025 12:20, Sabrina Dubroca wrote:
>>>>> 2025-03-05, 00:19:32 +0100, Antonio Quartulli wrote:
>>>>>> On 04/03/2025 19:37, Sabrina Dubroca wrote:
>>>>>>> 2025-03-04, 01:33:48 +0100, Antonio Quartulli wrote:
>>>>>>>> +void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb)
>>>>>>>> +{
>>>>>>>> + struct hlist_nulls_head *nhead;
>>>>>>>> + struct sockaddr_storage ss;
>>>>>>>> + const u8 *local_ip = NULL;
>>>>>>>> + struct sockaddr_in6 *sa6;
>>>>>>>> + struct sockaddr_in *sa;
>>>>>>>> + struct ovpn_bind *bind;
>>>>>>>> + size_t salen = 0;
>>>>>>>> +
>>>>>>>> + spin_lock_bh(&peer->lock);
>>>>>>>> + bind = rcu_dereference_protected(peer->bind,
>>>>>>>> + lockdep_is_held(&peer->lock));
>>>>>>>> + if (unlikely(!bind))
>>>>>>>> + goto unlock;
>>>>>>>> +
>>>>>>>> + switch (skb->protocol) {
>>>>>>>> + case htons(ETH_P_IP):
>>>>>>>> + /* float check */
>>>>>>>> + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) {
>>>>>>>> + if (bind->remote.in4.sin_family == AF_INET)
>>>>>>>> + local_ip = (u8 *)&bind->local;
>>>>>>>
>>>>>>> If I'm reading this correctly, we always reuse the existing local
>>>>>>> address when we have to re-create the bind, even if it doesn't match
>>>>>>> the skb? The "local endpoint update" chunk below is doing that, but
>>>>>>> only if we're keeping the same remote? It'll get updated the next time
>>>>>>> we receive a packet and call ovpn_peer_endpoints_update.
>>>>>>>
>>>>>>> That might irritate the RPF check on the other side, if we still use
>>>>>>> our "old" source to talk to the new dest?
>>>>>>>
>>>>>>>> + sa = (struct sockaddr_in *)&ss;
>>>>>>>> + sa->sin_family = AF_INET;
>>>>>>>> + sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
>>>>>>>> + sa->sin_port = udp_hdr(skb)->source;
>>>>>>>> + salen = sizeof(*sa);
>>>>>>>> + break;
>>>>>>
>>>>>> I think the issue is simply this 'break' above - by removing it, everything
>>>>>> should work as expected.
>>>>>
>>>>> Only if the bind was of the correct family? Checking an IPv4 local
>>>>> address (in the bind) against an IPv6 source address in the packet (or
>>>>> the other way around) isn't going to work well.
>>>>
>>>> Ah I understand what you mean.
>>>>
>>>> The purpose of "local_ip" is to provide a working local endpoint to be used
>>>> with the new remote address.
>>>> However, if the float is switching family we can't re-use the same old local
>>>> endpoint (hence the check).
>>>> In this case we'll learn the "new" local address later.
>>>>
>>>> Does it make sense?
>>>
>>> Sure, but we could have learned it immediately from the packet we just
>>> got, whether we're changing family or not. No need to wait for the
>>> next RX packet to also learn the new local address.
>>
>> Indeed.
>>
>>>
>>> But if we now do a dst_cache_reset with the peer float,
>>> ovpn_udp*_output will have to do a new route/local address lookup and
>>> I guess that should clean up the local address stored in the bind, and
>>> then update the dst_cache with the local address we just found.
>>
>> Right and this may not truly be what we want.
>>
>> If peer X is sending packets to our IP1, we should at least try to reply
>> from the same address.
>>
>> If we have two IPs, IP1 and IP2, and both can be used to reach peer X, we
>> should always try to use the one where we received traffic from X in the
>> first place.
>
> I had a thought that it might not be our prefered address to talk to
> X, but it would probably be, since we decided to use it (and thus X
> used it as remote to talk to us).
I am not sure I follow this sentence: I think you are just confirming
what I said above (please correct me if I am wrong)?
>
>> OTOH hand it is also true that with floating detection on both sides, the
>> situation will converge quickly, but there might be a reason why X chose IP1
>> as destination, therefore we should do our best to respect that.
>
> And I guess the primary reason for X to choose IP1 would be "we sent
> packets to X from IP1".
Probably. It truly depends on who initiated the connection.
>
>> So, even in case of float, we should still store the local endpoint and
>> attempt fetching a route that takes that into consideration.
>> Which I think is what is happening (assuming we reset the dst_cache on
>> float).
>
> Not at the same time as float, unless ovpn_peer_endpoints_update sets
> local_ip = ip_hdr(skb)->daddr unconditionally on float?
>
> Otherwise the next route lookup in ovpn_udpX_output will pick whatever
> source address it wants (which would likely match what's in the
> received skb during float, so probably fine anyway).
>
But that's what the code just below in ovpn_peer_endpoints_update()
does, no?
223 /* local endpoint update */
224 if (unlikely(bind->local.ipv4.s_addr !=
ip_hdr(skb)->daddr)) {
...
229 bind->local.ipv4.s_addr = ip_hdr(skb)->daddr;
>> ovpn_udpX_output() will:
>> * get no rt from the cache
>> * possibly confirm that saddr is ok
>> * fetch the new rt using the provided saddr and daddr
>> * update the cache.
>>
>> That makes sense to me.
>> Would you agree?
>
> With dst_cache reset on float, yes. As long as we have that, the main
> behavior seems correct to me. (maybe some corner cases will not be
> handled optimally, but that can be improved later - which is most
> likely what I've been discussing in these emails :))
Yeah :)
>
> [this could be a useful counter to add in the future: number of floats
> and local address updates - so the user can check if that's increasing
> "too often", which would indicate something weird is happening]
ACK, good idea!
Thanks!
Ok, I'll probably wait a little more and then prepare v22.
Cheers,
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 18/24] ovpn: add support for peer floating
2025-03-10 12:57 ` Antonio Quartulli
@ 2025-03-10 22:32 ` Sabrina Dubroca
0 siblings, 0 replies; 46+ messages in thread
From: Sabrina Dubroca @ 2025-03-10 22:32 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
Note: as I tried to say at the end of my previous reply, feel free to
ignore this or save it for later. dst_cache_reset on float and change
of remote via netlink peer_modify is the important thing, and I'm not
sure the "local address change on float" can or can't happen.
2025-03-10, 13:57:09 +0100, Antonio Quartulli wrote:
> On 07/03/2025 11:12, Sabrina Dubroca wrote:
> > 2025-03-06, 11:02:50 +0100, Antonio Quartulli wrote:
> > > On 05/03/2025 17:56, Sabrina Dubroca wrote:
> > > > 2025-03-05, 14:14:36 +0100, Antonio Quartulli wrote:
> > > > > On 05/03/2025 12:20, Sabrina Dubroca wrote:
> > > > > > 2025-03-05, 00:19:32 +0100, Antonio Quartulli wrote:
> > > > > > > On 04/03/2025 19:37, Sabrina Dubroca wrote:
> > > > > > > > 2025-03-04, 01:33:48 +0100, Antonio Quartulli wrote:
> > > > > > > > > +void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb)
> > > > > > > > > +{
> > > > > > > > > + struct hlist_nulls_head *nhead;
> > > > > > > > > + struct sockaddr_storage ss;
> > > > > > > > > + const u8 *local_ip = NULL;
> > > > > > > > > + struct sockaddr_in6 *sa6;
> > > > > > > > > + struct sockaddr_in *sa;
> > > > > > > > > + struct ovpn_bind *bind;
> > > > > > > > > + size_t salen = 0;
> > > > > > > > > +
> > > > > > > > > + spin_lock_bh(&peer->lock);
> > > > > > > > > + bind = rcu_dereference_protected(peer->bind,
> > > > > > > > > + lockdep_is_held(&peer->lock));
> > > > > > > > > + if (unlikely(!bind))
> > > > > > > > > + goto unlock;
> > > > > > > > > +
> > > > > > > > > + switch (skb->protocol) {
> > > > > > > > > + case htons(ETH_P_IP):
> > > > > > > > > + /* float check */
> > > > > > > > > + if (unlikely(!ovpn_bind_skb_src_match(bind, skb))) {
> > > > > > > > > + if (bind->remote.in4.sin_family == AF_INET)
> > > > > > > > > + local_ip = (u8 *)&bind->local;
> > > > > > > >
> > > > > > > > If I'm reading this correctly, we always reuse the existing local
> > > > > > > > address when we have to re-create the bind, even if it doesn't match
> > > > > > > > the skb? The "local endpoint update" chunk below is doing that, but
> > > > > > > > only if we're keeping the same remote? It'll get updated the next time
> > > > > > > > we receive a packet and call ovpn_peer_endpoints_update.
> > > > > > > >
> > > > > > > > That might irritate the RPF check on the other side, if we still use
> > > > > > > > our "old" source to talk to the new dest?
> > > > > > > >
> > > > > > > > > + sa = (struct sockaddr_in *)&ss;
> > > > > > > > > + sa->sin_family = AF_INET;
> > > > > > > > > + sa->sin_addr.s_addr = ip_hdr(skb)->saddr;
> > > > > > > > > + sa->sin_port = udp_hdr(skb)->source;
> > > > > > > > > + salen = sizeof(*sa);
> > > > > > > > > + break;
> > > > > > >
> > > > > > > I think the issue is simply this 'break' above - by removing it, everything
> > > > > > > should work as expected.
> > > > > >
> > > > > > Only if the bind was of the correct family? Checking an IPv4 local
> > > > > > address (in the bind) against an IPv6 source address in the packet (or
> > > > > > the other way around) isn't going to work well.
> > > > >
> > > > > Ah I understand what you mean.
> > > > >
> > > > > The purpose of "local_ip" is to provide a working local endpoint to be used
> > > > > with the new remote address.
> > > > > However, if the float is switching family we can't re-use the same old local
> > > > > endpoint (hence the check).
> > > > > In this case we'll learn the "new" local address later.
> > > > >
> > > > > Does it make sense?
> > > >
> > > > Sure, but we could have learned it immediately from the packet we just
> > > > got, whether we're changing family or not. No need to wait for the
> > > > next RX packet to also learn the new local address.
> > >
> > > Indeed.
> > >
> > > >
> > > > But if we now do a dst_cache_reset with the peer float,
> > > > ovpn_udp*_output will have to do a new route/local address lookup and
> > > > I guess that should clean up the local address stored in the bind, and
> > > > then update the dst_cache with the local address we just found.
> > >
> > > Right and this may not truly be what we want.
> > >
> > > If peer X is sending packets to our IP1, we should at least try to reply
> > > from the same address.
> > >
> > > If we have two IPs, IP1 and IP2, and both can be used to reach peer X, we
> > > should always try to use the one where we received traffic from X in the
> > > first place.
> >
> > I had a thought that it might not be our prefered address to talk to
> > X, but it would probably be, since we decided to use it (and thus X
> > used it as remote to talk to us).
>
> I am not sure I follow this sentence: I think you are just confirming what I
> said above (please correct me if I am wrong)?
Yes. This may turn out to be incorrect (see the "some corner cases"
bit below), but let's wait for examples of that.
> > > OTOH hand it is also true that with floating detection on both sides, the
> > > situation will converge quickly, but there might be a reason why X chose IP1
> > > as destination, therefore we should do our best to respect that.
> >
> > And I guess the primary reason for X to choose IP1 would be "we sent
> > packets to X from IP1".
>
> Probably. It truly depends on who initiated the connection.
>
> >
> > > So, even in case of float, we should still store the local endpoint and
> > > attempt fetching a route that takes that into consideration.
> > > Which I think is what is happening (assuming we reset the dst_cache on
> > > float).
> >
> > Not at the same time as float, unless ovpn_peer_endpoints_update sets
> > local_ip = ip_hdr(skb)->daddr unconditionally on float?
> >
> > Otherwise the next route lookup in ovpn_udpX_output will pick whatever
> > source address it wants (which would likely match what's in the
> > received skb during float, so probably fine anyway).
> >
>
> But that's what the code just below in ovpn_peer_endpoints_update() does,
> no?
I think this is going a bit in circles :) And possibly completely
irrelevant.
The /* local endpoint update */ is (correctly) skipped in case of
float [because the family may not be right so we can't compare
addresses].
In case of float, I think setting local_ip to the packet's header
would do the right thing is all cases:
- if it matches what's in the old bind, great, we didn't change our
local IP, just the remote and we could have kept local_ip = &bind->local
- if it doesn't match, we learn it (but that brings the question: why
did the peer think our address was IP2 and we thought it was IP1? --
which may be an irrelevant corner case)
>
> 223 /* local endpoint update */
> 224 if (unlikely(bind->local.ipv4.s_addr !=
> ip_hdr(skb)->daddr)) {
>
> ...
>
> 229 bind->local.ipv4.s_addr = ip_hdr(skb)->daddr;
>
>
> > > ovpn_udpX_output() will:
> > > * get no rt from the cache
> > > * possibly confirm that saddr is ok
> > > * fetch the new rt using the provided saddr and daddr
> > > * update the cache.
> > >
> > > That makes sense to me.
> > > Would you agree?
> >
> > With dst_cache reset on float, yes. As long as we have that, the main
> > behavior seems correct to me. (maybe some corner cases will not be
> > handled optimally, but that can be improved later - which is most
> > likely what I've been discussing in these emails :))
>
> Yeah :)
> >
> > [this could be a useful counter to add in the future: number of floats
> > and local address updates - so the user can check if that's increasing
> > "too often", which would indicate something weird is happening]
>
> ACK, good idea!
>
> Thanks!
>
> Ok, I'll probably wait a little more and then prepare v22.
I won't be able to look at it until the week-end. But if you're ready,
you can go ahead and post it anyway.
--
Sabrina
^ permalink raw reply [flat|nested] 46+ messages in thread
* [PATCH v21 19/24] ovpn: implement peer add/get/dump/delete via netlink
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (17 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 18/24] ovpn: add support for peer floating Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 14:35 ` Sabrina Dubroca
2025-03-04 0:33 ` [PATCH v21 20/24] ovpn: implement key add/get/del/swap " Antonio Quartulli
` (4 subsequent siblings)
23 siblings, 1 reply; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
This change introduces the netlink command needed to add, delete and
retrieve/dump known peers. Userspace is expected to use these commands
to handle known peer lifecycles.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/netlink.c | 677 ++++++++++++++++++++++++++++++++++++++++++++-
drivers/net/ovpn/peer.c | 62 +++--
drivers/net/ovpn/peer.h | 5 +
drivers/net/ovpn/socket.c | 4 +-
4 files changed, 722 insertions(+), 26 deletions(-)
diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c
index 8d267d4c82283d9b5f989478102086ce385195d5..9824ce4437e63e602d37d31105fb9ac06f99d421 100644
--- a/drivers/net/ovpn/netlink.c
+++ b/drivers/net/ovpn/netlink.c
@@ -7,6 +7,7 @@
*/
#include <linux/netdevice.h>
+#include <linux/types.h>
#include <net/genetlink.h>
#include <uapi/linux/ovpn.h>
@@ -15,6 +16,9 @@
#include "main.h"
#include "netlink.h"
#include "netlink-gen.h"
+#include "bind.h"
+#include "peer.h"
+#include "socket.h"
MODULE_ALIAS_GENL_FAMILY(OVPN_FAMILY_NAME);
@@ -89,29 +93,692 @@ void ovpn_nl_post_doit(const struct genl_split_ops *ops, struct sk_buff *skb,
netdev_put(ovpn->dev, tracker);
}
+static bool ovpn_nl_attr_sockaddr_remote(struct nlattr **attrs,
+ struct sockaddr_storage *ss)
+{
+ struct sockaddr_in6 *sin6;
+ struct sockaddr_in *sin;
+ struct in6_addr *in6;
+ __be16 port = 0;
+ __be32 *in;
+
+ ss->ss_family = AF_UNSPEC;
+
+ if (attrs[OVPN_A_PEER_REMOTE_PORT])
+ port = nla_get_be16(attrs[OVPN_A_PEER_REMOTE_PORT]);
+
+ if (attrs[OVPN_A_PEER_REMOTE_IPV4]) {
+ ss->ss_family = AF_INET;
+ in = nla_data(attrs[OVPN_A_PEER_REMOTE_IPV4]);
+ } else if (attrs[OVPN_A_PEER_REMOTE_IPV6]) {
+ ss->ss_family = AF_INET6;
+ in6 = nla_data(attrs[OVPN_A_PEER_REMOTE_IPV6]);
+ } else {
+ return false;
+ }
+
+ switch (ss->ss_family) {
+ case AF_INET6:
+ /* If this is a regular IPv6 just break and move on,
+ * otherwise switch to AF_INET and extract the IPv4 accordingly
+ */
+ if (!ipv6_addr_v4mapped(in6)) {
+ sin6 = (struct sockaddr_in6 *)ss;
+ sin6->sin6_port = port;
+ memcpy(&sin6->sin6_addr, in6, sizeof(*in6));
+ break;
+ }
+
+ /* v4-mapped-v6 address */
+ ss->ss_family = AF_INET;
+ in = &in6->s6_addr32[3];
+ fallthrough;
+ case AF_INET:
+ sin = (struct sockaddr_in *)ss;
+ sin->sin_port = port;
+ sin->sin_addr.s_addr = *in;
+ break;
+ }
+
+ return true;
+}
+
+static u8 *ovpn_nl_attr_local_ip(struct nlattr **attrs)
+{
+ u8 *addr6;
+
+ if (!attrs[OVPN_A_PEER_LOCAL_IPV4] && !attrs[OVPN_A_PEER_LOCAL_IPV6])
+ return NULL;
+
+ if (attrs[OVPN_A_PEER_LOCAL_IPV4])
+ return nla_data(attrs[OVPN_A_PEER_LOCAL_IPV4]);
+
+ addr6 = nla_data(attrs[OVPN_A_PEER_LOCAL_IPV6]);
+ /* this is an IPv4-mapped IPv6 address, therefore extract the actual
+ * v4 address from the last 4 bytes
+ */
+ if (ipv6_addr_v4mapped((struct in6_addr *)addr6))
+ return addr6 + 12;
+
+ return addr6;
+}
+
+static sa_family_t ovpn_nl_family_get(struct nlattr *addr4,
+ struct nlattr *addr6)
+{
+ if (addr4)
+ return AF_INET;
+
+ if (addr6) {
+ if (ipv6_addr_v4mapped((struct in6_addr *)nla_data(addr6)))
+ return AF_INET;
+ return AF_INET6;
+ }
+
+ return AF_UNSPEC;
+}
+
+static int ovpn_nl_peer_precheck(struct ovpn_priv *ovpn,
+ struct genl_info *info,
+ struct nlattr **attrs)
+{
+ sa_family_t local_fam, remote_fam;
+
+ if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_PEER], attrs,
+ OVPN_A_PEER_ID))
+ return -EINVAL;
+
+ if (attrs[OVPN_A_PEER_REMOTE_IPV4] && attrs[OVPN_A_PEER_REMOTE_IPV6]) {
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "cannot specify both remote IPv4 or IPv6 address");
+ return -EINVAL;
+ }
+
+ if (!attrs[OVPN_A_PEER_REMOTE_IPV4] &&
+ !attrs[OVPN_A_PEER_REMOTE_IPV6] && attrs[OVPN_A_PEER_REMOTE_PORT]) {
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "cannot specify remote port without IP address");
+ return -EINVAL;
+ }
+
+ if (!attrs[OVPN_A_PEER_REMOTE_IPV4] &&
+ attrs[OVPN_A_PEER_LOCAL_IPV4]) {
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "cannot specify local IPv4 address without remote");
+ return -EINVAL;
+ }
+
+ if (!attrs[OVPN_A_PEER_REMOTE_IPV6] &&
+ attrs[OVPN_A_PEER_LOCAL_IPV6]) {
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "cannot specify local IPV6 address without remote");
+ return -EINVAL;
+ }
+
+ /* check that local and remote address families are the same even
+ * after parsing v4mapped IPv6 addresses.
+ * (if addresses are not provided, family will be AF_UNSPEC and
+ * the check is skipped)
+ */
+ local_fam = ovpn_nl_family_get(attrs[OVPN_A_PEER_LOCAL_IPV4],
+ attrs[OVPN_A_PEER_LOCAL_IPV6]);
+ remote_fam = ovpn_nl_family_get(attrs[OVPN_A_PEER_REMOTE_IPV4],
+ attrs[OVPN_A_PEER_REMOTE_IPV6]);
+ if (local_fam != AF_UNSPEC && remote_fam != AF_UNSPEC &&
+ local_fam != remote_fam) {
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "mismatching local and remote address families");
+ return -EINVAL;
+ }
+
+ if (remote_fam != AF_INET6 && attrs[OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID]) {
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "cannot specify scope id without remote IPv6 address");
+ return -EINVAL;
+ }
+
+ /* VPN IPs are needed only in MP mode for selecting the right peer */
+ if (ovpn->mode == OVPN_MODE_P2P && (attrs[OVPN_A_PEER_VPN_IPV4] ||
+ attrs[OVPN_A_PEER_VPN_IPV6])) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "unexpected VPN IP in P2P mode");
+ return -EINVAL;
+ }
+
+ if ((attrs[OVPN_A_PEER_KEEPALIVE_INTERVAL] &&
+ !attrs[OVPN_A_PEER_KEEPALIVE_TIMEOUT]) ||
+ (!attrs[OVPN_A_PEER_KEEPALIVE_INTERVAL] &&
+ attrs[OVPN_A_PEER_KEEPALIVE_TIMEOUT])) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "keepalive interval and timeout are required together");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/**
+ * ovpn_nl_peer_modify - modify the peer attributes according to the incoming msg
+ * @peer: the peer to modify
+ * @info: generic netlink info from the user request
+ * @attrs: the attributes from the user request
+ *
+ * Return: a negative error code in case of failure, 0 on success or 1 on
+ * success and the VPN IPs have been modified (requires rehashing in MP
+ * mode)
+ */
+static int ovpn_nl_peer_modify(struct ovpn_peer *peer, struct genl_info *info,
+ struct nlattr **attrs)
+{
+ struct sockaddr_storage ss = {};
+ u32 interv, timeout;
+ u8 *local_ip = NULL;
+ bool rehash = false;
+ int ret;
+
+ spin_lock_bh(&peer->lock);
+
+ if (ovpn_nl_attr_sockaddr_remote(attrs, &ss)) {
+ /* we carry the local IP in a generic container.
+ * ovpn_peer_reset_sockaddr() will properly interpret it
+ * based on ss.ss_family
+ */
+ local_ip = ovpn_nl_attr_local_ip(attrs);
+
+ /* set peer sockaddr */
+ ret = ovpn_peer_reset_sockaddr(peer, &ss, local_ip);
+ if (ret < 0) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "cannot set peer sockaddr: %d",
+ ret);
+ goto err_unlock;
+ }
+ }
+
+ if (attrs[OVPN_A_PEER_VPN_IPV4]) {
+ rehash = true;
+ peer->vpn_addrs.ipv4.s_addr =
+ nla_get_in_addr(attrs[OVPN_A_PEER_VPN_IPV4]);
+ }
+
+ if (attrs[OVPN_A_PEER_VPN_IPV6]) {
+ rehash = true;
+ peer->vpn_addrs.ipv6 =
+ nla_get_in6_addr(attrs[OVPN_A_PEER_VPN_IPV6]);
+ }
+
+ /* when setting the keepalive, both parameters have to be configured */
+ if (attrs[OVPN_A_PEER_KEEPALIVE_INTERVAL] &&
+ attrs[OVPN_A_PEER_KEEPALIVE_TIMEOUT]) {
+ interv = nla_get_u32(attrs[OVPN_A_PEER_KEEPALIVE_INTERVAL]);
+ timeout = nla_get_u32(attrs[OVPN_A_PEER_KEEPALIVE_TIMEOUT]);
+ ovpn_peer_keepalive_set(peer, interv, timeout);
+ }
+
+ netdev_dbg(peer->ovpn->dev,
+ "modify peer id=%u endpoint=%pIScp VPN-IPv4=%pI4 VPN-IPv6=%pI6c\n",
+ peer->id, &ss,
+ &peer->vpn_addrs.ipv4.s_addr, &peer->vpn_addrs.ipv6);
+
+ spin_unlock_bh(&peer->lock);
+
+ return rehash ? 1 : 0;
+err_unlock:
+ spin_unlock_bh(&peer->lock);
+ return ret;
+}
+
int ovpn_nl_peer_new_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct nlattr *attrs[OVPN_A_PEER_MAX + 1];
+ struct ovpn_priv *ovpn = info->user_ptr[0];
+ struct ovpn_socket *ovpn_sock;
+ struct socket *sock = NULL;
+ struct ovpn_peer *peer;
+ u32 sockfd, peer_id;
+ int ret;
+
+ if (GENL_REQ_ATTR_CHECK(info, OVPN_A_PEER))
+ return -EINVAL;
+
+ ret = nla_parse_nested(attrs, OVPN_A_PEER_MAX, info->attrs[OVPN_A_PEER],
+ ovpn_peer_nl_policy, info->extack);
+ if (ret)
+ return ret;
+
+ ret = ovpn_nl_peer_precheck(ovpn, info, attrs);
+ if (ret < 0)
+ return ret;
+
+ if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_PEER], attrs,
+ OVPN_A_PEER_SOCKET))
+ return -EINVAL;
+
+ /* in MP mode VPN IPs are required for selecting the right peer */
+ if (ovpn->mode == OVPN_MODE_MP && !attrs[OVPN_A_PEER_VPN_IPV4] &&
+ !attrs[OVPN_A_PEER_VPN_IPV6]) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "VPN IP must be provided in MP mode");
+ return -EINVAL;
+ }
+
+ peer_id = nla_get_u32(attrs[OVPN_A_PEER_ID]);
+ peer = ovpn_peer_new(ovpn, peer_id);
+ if (IS_ERR(peer)) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "cannot create new peer object for peer %u: %ld",
+ peer_id, PTR_ERR(peer));
+ return PTR_ERR(peer);
+ }
+
+ /* lookup the fd in the kernel table and extract the socket object */
+ sockfd = nla_get_u32(attrs[OVPN_A_PEER_SOCKET]);
+ /* sockfd_lookup() increases sock's refcounter */
+ sock = sockfd_lookup(sockfd, &ret);
+ if (!sock) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "cannot lookup peer socket (fd=%u): %d",
+ sockfd, ret);
+ ret = -ENOTSOCK;
+ goto peer_release;
+ }
+
+ /* Only when using UDP as transport protocol the remote endpoint
+ * can be configured so that ovpn knows where to send packets to.
+ */
+ if (sock->sk->sk_protocol == IPPROTO_UDP &&
+ !attrs[OVPN_A_PEER_REMOTE_IPV4] &&
+ !attrs[OVPN_A_PEER_REMOTE_IPV6]) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "missing remote IP address for UDP socket");
+ sockfd_put(sock);
+ ret = -EINVAL;
+ goto peer_release;
+ }
+
+ /* In case of TCP, the socket is connected to the peer and ovpn
+ * will just send bytes over it, without the need to specify a
+ * destination.
+ */
+ if (sock->sk->sk_protocol == IPPROTO_TCP &&
+ (attrs[OVPN_A_PEER_REMOTE_IPV4] ||
+ attrs[OVPN_A_PEER_REMOTE_IPV6])) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "unexpected remote IP address with TCP socket");
+ sockfd_put(sock);
+ ret = -EINVAL;
+ goto peer_release;
+ }
+
+ ovpn_sock = ovpn_socket_new(sock, peer);
+ /* at this point we unconditionally drop the reference to the socket:
+ * - in case of error, the socket has to be dropped
+ * - if case of success, the socket is configured and let
+ * userspace own the reference, so that the latter can
+ * trigger the final close()
+ */
+ sockfd_put(sock);
+ if (IS_ERR(ovpn_sock)) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "cannot encapsulate socket: %ld",
+ PTR_ERR(ovpn_sock));
+ ret = -ENOTSOCK;
+ goto peer_release;
+ }
+
+ rcu_assign_pointer(peer->sock, ovpn_sock);
+
+ ret = ovpn_nl_peer_modify(peer, info, attrs);
+ if (ret < 0)
+ goto sock_release;
+
+ ret = ovpn_peer_add(ovpn, peer);
+ if (ret < 0) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "cannot add new peer (id=%u) to hashtable: %d",
+ peer->id, ret);
+ goto sock_release;
+ }
+
+ return 0;
+
+sock_release:
+ ovpn_socket_release(peer);
+peer_release:
+ /* release right away because peer was not yet hashed, thus it is not
+ * used in any context
+ */
+ ovpn_peer_release(peer);
+
+ return ret;
}
int ovpn_nl_peer_set_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct nlattr *attrs[OVPN_A_PEER_MAX + 1];
+ struct ovpn_priv *ovpn = info->user_ptr[0];
+ struct ovpn_socket *sock;
+ struct ovpn_peer *peer;
+ u32 peer_id;
+ int ret;
+
+ if (GENL_REQ_ATTR_CHECK(info, OVPN_A_PEER))
+ return -EINVAL;
+
+ ret = nla_parse_nested(attrs, OVPN_A_PEER_MAX, info->attrs[OVPN_A_PEER],
+ ovpn_peer_nl_policy, info->extack);
+ if (ret)
+ return ret;
+
+ ret = ovpn_nl_peer_precheck(ovpn, info, attrs);
+ if (ret < 0)
+ return ret;
+
+ if (attrs[OVPN_A_PEER_SOCKET]) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "socket cannot be modified");
+ return -EINVAL;
+ }
+
+ peer_id = nla_get_u32(attrs[OVPN_A_PEER_ID]);
+ peer = ovpn_peer_get_by_id(ovpn, peer_id);
+ if (!peer) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "cannot find peer with id %u", peer_id);
+ return -ENOENT;
+ }
+
+ /* when using a TCP socket the remote IP is not expected */
+ rcu_read_lock();
+ sock = rcu_dereference(peer->sock);
+ if (sock && sock->sock->sk->sk_protocol == IPPROTO_TCP &&
+ (attrs[OVPN_A_PEER_REMOTE_IPV4] ||
+ attrs[OVPN_A_PEER_REMOTE_IPV6])) {
+ rcu_read_unlock();
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "unexpected remote IP address with TCP socket");
+ ovpn_peer_put(peer);
+ return -EINVAL;
+ }
+ rcu_read_unlock();
+
+ spin_lock_bh(&ovpn->lock);
+ ret = ovpn_nl_peer_modify(peer, info, attrs);
+ if (ret < 0) {
+ spin_unlock_bh(&ovpn->lock);
+ ovpn_peer_put(peer);
+ return ret;
+ }
+
+ /* ret == 1 means that VPN IPv4/6 has been modified and rehashing
+ * is required
+ */
+ if (ret > 0)
+ ovpn_peer_hash_vpn_ip(peer);
+ spin_unlock_bh(&ovpn->lock);
+ ovpn_peer_put(peer);
+
+ return 0;
+}
+
+static int ovpn_nl_send_peer(struct sk_buff *skb, const struct genl_info *info,
+ const struct ovpn_peer *peer, u32 portid, u32 seq,
+ int flags)
+{
+ const struct ovpn_bind *bind;
+ struct ovpn_socket *sock;
+ int ret = -EMSGSIZE;
+ struct nlattr *attr;
+ __be16 local_port;
+ void *hdr;
+ int id;
+
+ hdr = genlmsg_put(skb, portid, seq, &ovpn_nl_family, flags,
+ OVPN_CMD_PEER_GET);
+ if (!hdr)
+ return -ENOBUFS;
+
+ attr = nla_nest_start(skb, OVPN_A_PEER);
+ if (!attr)
+ goto err;
+
+ rcu_read_lock();
+ sock = rcu_dereference(peer->sock);
+ if (!sock) {
+ ret = -EINVAL;
+ goto err_unlock;
+ }
+
+ if (!net_eq(genl_info_net(info), sock_net(sock->sock->sk))) {
+ id = peernet2id_alloc(genl_info_net(info),
+ sock_net(sock->sock->sk),
+ GFP_ATOMIC);
+ if (nla_put_s32(skb, OVPN_A_PEER_SOCKET_NETNSID, id))
+ goto err_unlock;
+ }
+ local_port = inet_sk(sock->sock->sk)->inet_sport;
+ rcu_read_unlock();
+
+ if (nla_put_u32(skb, OVPN_A_PEER_ID, peer->id))
+ goto err;
+
+ if (peer->vpn_addrs.ipv4.s_addr != htonl(INADDR_ANY))
+ if (nla_put_in_addr(skb, OVPN_A_PEER_VPN_IPV4,
+ peer->vpn_addrs.ipv4.s_addr))
+ goto err;
+
+ if (!ipv6_addr_equal(&peer->vpn_addrs.ipv6, &in6addr_any))
+ if (nla_put_in6_addr(skb, OVPN_A_PEER_VPN_IPV6,
+ &peer->vpn_addrs.ipv6))
+ goto err;
+
+ if (nla_put_u32(skb, OVPN_A_PEER_KEEPALIVE_INTERVAL,
+ peer->keepalive_interval) ||
+ nla_put_u32(skb, OVPN_A_PEER_KEEPALIVE_TIMEOUT,
+ peer->keepalive_timeout))
+ goto err;
+
+ rcu_read_lock();
+ bind = rcu_dereference(peer->bind);
+ if (bind) {
+ if (bind->remote.in4.sin_family == AF_INET) {
+ if (nla_put_in_addr(skb, OVPN_A_PEER_REMOTE_IPV4,
+ bind->remote.in4.sin_addr.s_addr) ||
+ nla_put_net16(skb, OVPN_A_PEER_REMOTE_PORT,
+ bind->remote.in4.sin_port) ||
+ nla_put_in_addr(skb, OVPN_A_PEER_LOCAL_IPV4,
+ bind->local.ipv4.s_addr))
+ goto err_unlock;
+ } else if (bind->remote.in4.sin_family == AF_INET6) {
+ if (nla_put_in6_addr(skb, OVPN_A_PEER_REMOTE_IPV6,
+ &bind->remote.in6.sin6_addr) ||
+ nla_put_u32(skb, OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID,
+ bind->remote.in6.sin6_scope_id) ||
+ nla_put_net16(skb, OVPN_A_PEER_REMOTE_PORT,
+ bind->remote.in6.sin6_port) ||
+ nla_put_in6_addr(skb, OVPN_A_PEER_LOCAL_IPV6,
+ &bind->local.ipv6))
+ goto err_unlock;
+ }
+ }
+ rcu_read_unlock();
+
+ if (nla_put_net16(skb, OVPN_A_PEER_LOCAL_PORT, local_port) ||
+ /* VPN RX stats */
+ nla_put_uint(skb, OVPN_A_PEER_VPN_RX_BYTES,
+ atomic64_read(&peer->vpn_stats.rx.bytes)) ||
+ nla_put_uint(skb, OVPN_A_PEER_VPN_RX_PACKETS,
+ atomic64_read(&peer->vpn_stats.rx.packets)) ||
+ /* VPN TX stats */
+ nla_put_uint(skb, OVPN_A_PEER_VPN_TX_BYTES,
+ atomic64_read(&peer->vpn_stats.tx.bytes)) ||
+ nla_put_uint(skb, OVPN_A_PEER_VPN_TX_PACKETS,
+ atomic64_read(&peer->vpn_stats.tx.packets)) ||
+ /* link RX stats */
+ nla_put_uint(skb, OVPN_A_PEER_LINK_RX_BYTES,
+ atomic64_read(&peer->link_stats.rx.bytes)) ||
+ nla_put_uint(skb, OVPN_A_PEER_LINK_RX_PACKETS,
+ atomic64_read(&peer->link_stats.rx.packets)) ||
+ /* link TX stats */
+ nla_put_uint(skb, OVPN_A_PEER_LINK_TX_BYTES,
+ atomic64_read(&peer->link_stats.tx.bytes)) ||
+ nla_put_uint(skb, OVPN_A_PEER_LINK_TX_PACKETS,
+ atomic64_read(&peer->link_stats.tx.packets)))
+ goto err;
+
+ nla_nest_end(skb, attr);
+ genlmsg_end(skb, hdr);
+
+ return 0;
+err_unlock:
+ rcu_read_unlock();
+err:
+ genlmsg_cancel(skb, hdr);
+ return ret;
}
int ovpn_nl_peer_get_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct nlattr *attrs[OVPN_A_PEER_MAX + 1];
+ struct ovpn_priv *ovpn = info->user_ptr[0];
+ struct ovpn_peer *peer;
+ struct sk_buff *msg;
+ u32 peer_id;
+ int ret;
+
+ if (GENL_REQ_ATTR_CHECK(info, OVPN_A_PEER))
+ return -EINVAL;
+
+ ret = nla_parse_nested(attrs, OVPN_A_PEER_MAX, info->attrs[OVPN_A_PEER],
+ ovpn_peer_nl_policy, info->extack);
+ if (ret)
+ return ret;
+
+ if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_PEER], attrs,
+ OVPN_A_PEER_ID))
+ return -EINVAL;
+
+ peer_id = nla_get_u32(attrs[OVPN_A_PEER_ID]);
+ peer = ovpn_peer_get_by_id(ovpn, peer_id);
+ if (!peer) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "cannot find peer with id %u", peer_id);
+ return -ENOENT;
+ }
+
+ msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+ if (!msg) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ ret = ovpn_nl_send_peer(msg, info, peer, info->snd_portid,
+ info->snd_seq, 0);
+ if (ret < 0) {
+ nlmsg_free(msg);
+ goto err;
+ }
+
+ ret = genlmsg_reply(msg, info);
+err:
+ ovpn_peer_put(peer);
+ return ret;
}
int ovpn_nl_peer_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
{
- return -EOPNOTSUPP;
+ const struct genl_info *info = genl_info_dump(cb);
+ int bkt, last_idx = cb->args[1], dumped = 0;
+ netdevice_tracker tracker;
+ struct ovpn_priv *ovpn;
+ struct ovpn_peer *peer;
+
+ ovpn = ovpn_get_dev_from_attrs(sock_net(cb->skb->sk), info, &tracker);
+ if (IS_ERR(ovpn))
+ return PTR_ERR(ovpn);
+
+ if (ovpn->mode == OVPN_MODE_P2P) {
+ /* if we already dumped a peer it means we are done */
+ if (last_idx)
+ goto out;
+
+ rcu_read_lock();
+ peer = rcu_dereference(ovpn->peer);
+ if (peer) {
+ if (ovpn_nl_send_peer(skb, info, peer,
+ NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq,
+ NLM_F_MULTI) == 0)
+ dumped++;
+ }
+ rcu_read_unlock();
+ } else {
+ rcu_read_lock();
+ hash_for_each_rcu(ovpn->peers->by_id, bkt, peer,
+ hash_entry_id) {
+ /* skip already dumped peers that were dumped by
+ * previous invocations
+ */
+ if (last_idx > 0) {
+ last_idx--;
+ continue;
+ }
+
+ if (ovpn_nl_send_peer(skb, info, peer,
+ NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq,
+ NLM_F_MULTI) < 0)
+ break;
+
+ /* count peers being dumped during this invocation */
+ dumped++;
+ }
+ rcu_read_unlock();
+ }
+
+out:
+ netdev_put(ovpn->dev, &tracker);
+
+ /* sum up peers dumped in this message, so that at the next invocation
+ * we can continue from where we left
+ */
+ cb->args[1] += dumped;
+ return skb->len;
}
int ovpn_nl_peer_del_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct nlattr *attrs[OVPN_A_PEER_MAX + 1];
+ struct ovpn_priv *ovpn = info->user_ptr[0];
+ struct ovpn_peer *peer;
+ u32 peer_id;
+ int ret;
+
+ if (GENL_REQ_ATTR_CHECK(info, OVPN_A_PEER))
+ return -EINVAL;
+
+ ret = nla_parse_nested(attrs, OVPN_A_PEER_MAX, info->attrs[OVPN_A_PEER],
+ ovpn_peer_nl_policy, info->extack);
+ if (ret)
+ return ret;
+
+ if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_PEER], attrs,
+ OVPN_A_PEER_ID))
+ return -EINVAL;
+
+ peer_id = nla_get_u32(attrs[OVPN_A_PEER_ID]);
+ peer = ovpn_peer_get_by_id(ovpn, peer_id);
+ if (!peer) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "cannot find peer with id %u", peer_id);
+ return -ENOENT;
+ }
+
+ netdev_dbg(ovpn->dev, "del peer %u\n", peer->id);
+ ret = ovpn_peer_del(peer, OVPN_DEL_PEER_REASON_USERSPACE);
+ ovpn_peer_put(peer);
+
+ return ret;
}
int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info)
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 156e45407e0a6e69f177a064053f81fe778a9dd8..2a9f373b7a2f684203677bdc7b5a147c41ea2daf 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -135,9 +135,9 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_priv *ovpn, u32 id)
*
* Return: 0 on success or a negative error code otherwise
*/
-static int ovpn_peer_reset_sockaddr(struct ovpn_peer *peer,
- const struct sockaddr_storage *ss,
- const u8 *local_ip)
+int ovpn_peer_reset_sockaddr(struct ovpn_peer *peer,
+ const struct sockaddr_storage *ss,
+ const u8 *local_ip)
{
struct ovpn_bind *bind;
size_t ip_len;
@@ -331,7 +331,7 @@ static void ovpn_peer_release_rcu(struct rcu_head *head)
* ovpn_peer_release - release peer private members
* @peer: the peer to release
*/
-static void ovpn_peer_release(struct ovpn_peer *peer)
+void ovpn_peer_release(struct ovpn_peer *peer)
{
ovpn_crypto_state_release(&peer->crypto);
spin_lock_bh(&peer->lock);
@@ -872,6 +872,37 @@ bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb,
return match;
}
+void ovpn_peer_hash_vpn_ip(struct ovpn_peer *peer)
+{
+ struct hlist_nulls_head *nhead;
+
+ lockdep_assert_held(&peer->ovpn->lock);
+
+ /* rehashing makes sense only in multipeer mode */
+ if (peer->ovpn->mode != OVPN_MODE_MP)
+ return;
+
+ if (peer->vpn_addrs.ipv4.s_addr != htonl(INADDR_ANY)) {
+ /* remove potential old hashing */
+ hlist_nulls_del_init_rcu(&peer->hash_entry_addr4);
+
+ nhead = ovpn_get_hash_head(peer->ovpn->peers->by_vpn_addr4,
+ &peer->vpn_addrs.ipv4,
+ sizeof(peer->vpn_addrs.ipv4));
+ hlist_nulls_add_head_rcu(&peer->hash_entry_addr4, nhead);
+ }
+
+ if (!ipv6_addr_any(&peer->vpn_addrs.ipv6)) {
+ /* remove potential old hashing */
+ hlist_nulls_del_init_rcu(&peer->hash_entry_addr6);
+
+ nhead = ovpn_get_hash_head(peer->ovpn->peers->by_vpn_addr6,
+ &peer->vpn_addrs.ipv6,
+ sizeof(peer->vpn_addrs.ipv6));
+ hlist_nulls_add_head_rcu(&peer->hash_entry_addr6, nhead);
+ }
+}
+
/**
* ovpn_peer_add_mp - add peer to related tables in a MP instance
* @ovpn: the instance to add the peer to
@@ -933,19 +964,7 @@ static int ovpn_peer_add_mp(struct ovpn_priv *ovpn, struct ovpn_peer *peer)
ovpn_get_hash_head(ovpn->peers->by_id, &peer->id,
sizeof(peer->id)));
- if (peer->vpn_addrs.ipv4.s_addr != htonl(INADDR_ANY)) {
- nhead = ovpn_get_hash_head(ovpn->peers->by_vpn_addr4,
- &peer->vpn_addrs.ipv4,
- sizeof(peer->vpn_addrs.ipv4));
- hlist_nulls_add_head_rcu(&peer->hash_entry_addr4, nhead);
- }
-
- if (!ipv6_addr_any(&peer->vpn_addrs.ipv6)) {
- nhead = ovpn_get_hash_head(ovpn->peers->by_vpn_addr6,
- &peer->vpn_addrs.ipv6,
- sizeof(peer->vpn_addrs.ipv6));
- hlist_nulls_add_head_rcu(&peer->hash_entry_addr6, nhead);
- }
+ ovpn_peer_hash_vpn_ip(peer);
out:
spin_unlock_bh(&ovpn->lock);
return ret;
@@ -1317,11 +1336,16 @@ void ovpn_peer_keepalive_work(struct work_struct *work)
/* prevent rearming if the interface is being destroyed */
if (next_run > 0 && ovpn->registered) {
+ time64_t delta = next_run - now;
+
netdev_dbg(ovpn->dev,
"scheduling keepalive work: now=%llu next_run=%llu delta=%llu\n",
- next_run, now, next_run - now);
+ next_run, now, delta > 0 ? delta : 0);
+ /* due to the waiting above, the next_run deadline may have
+ * passed: in this case we reschedule the worker immediately
+ */
schedule_delayed_work(&ovpn->keepalive_work,
- (next_run - now) * HZ);
+ delta * HZ > 0 ? delta * HZ : 0);
}
unlock_ovpn(ovpn, &release_list);
}
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index f1288734ff100ee76b0c41ebb6dc71725ea33261..4cddf3c795a5a472279d586027c1cf564f55c50a 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -125,6 +125,7 @@ static inline bool ovpn_peer_hold(struct ovpn_peer *peer)
return kref_get_unless_zero(&peer->refcount);
}
+void ovpn_peer_release(struct ovpn_peer *peer);
void ovpn_peer_release_kref(struct kref *kref);
/**
@@ -147,6 +148,7 @@ struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_priv *ovpn,
struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_priv *ovpn, u32 peer_id);
struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_priv *ovpn,
struct sk_buff *skb);
+void ovpn_peer_hash_vpn_ip(struct ovpn_peer *peer);
bool ovpn_peer_check_by_src(struct ovpn_priv *ovpn, struct sk_buff *skb,
struct ovpn_peer *peer);
@@ -154,5 +156,8 @@ void ovpn_peer_keepalive_set(struct ovpn_peer *peer, u32 interval, u32 timeout);
void ovpn_peer_keepalive_work(struct work_struct *work);
void ovpn_peer_endpoints_update(struct ovpn_peer *peer, struct sk_buff *skb);
+int ovpn_peer_reset_sockaddr(struct ovpn_peer *peer,
+ const struct sockaddr_storage *ss,
+ const u8 *local_ip);
#endif /* _NET_OVPN_OVPNPEER_H_ */
diff --git a/drivers/net/ovpn/socket.c b/drivers/net/ovpn/socket.c
index be20c500f373fb894d0df5e02ce1996cf386d195..6ecf40857651afbd0986793afeb2a2f66f336aaf 100644
--- a/drivers/net/ovpn/socket.c
+++ b/drivers/net/ovpn/socket.c
@@ -49,8 +49,8 @@ static bool ovpn_socket_put(struct ovpn_peer *peer, struct ovpn_socket *sock)
* ovpn_socket_release - release resources owned by socket user
* @peer: peer whose socket should be released
*
- * This function should be invoked when the user is shutting
- * down and wants to drop its link to the socket.
+ * This function should be invoked when the peer is being removed
+ * and wants to drop its link to the socket.
*
* In case of UDP, the detach routine will drop a reference to the
* ovpn netdev, pointed by the ovpn_socket.
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* Re: [PATCH v21 19/24] ovpn: implement peer add/get/dump/delete via netlink
2025-03-04 0:33 ` [PATCH v21 19/24] ovpn: implement peer add/get/dump/delete via netlink Antonio Quartulli
@ 2025-03-04 14:35 ` Sabrina Dubroca
2025-03-04 21:42 ` Antonio Quartulli
0 siblings, 1 reply; 46+ messages in thread
From: Sabrina Dubroca @ 2025-03-04 14:35 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
2025-03-04, 01:33:49 +0100, Antonio Quartulli wrote:
> @@ -1317,11 +1336,16 @@ void ovpn_peer_keepalive_work(struct work_struct *work)
>
> /* prevent rearming if the interface is being destroyed */
> if (next_run > 0 && ovpn->registered) {
> + time64_t delta = next_run - now;
> +
> netdev_dbg(ovpn->dev,
> "scheduling keepalive work: now=%llu next_run=%llu delta=%llu\n",
> - next_run, now, next_run - now);
> + next_run, now, delta > 0 ? delta : 0);
> + /* due to the waiting above, the next_run deadline may have
> + * passed: in this case we reschedule the worker immediately
> + */
I don't understand this bit. I don't see what waiting you're refering
to (in particular within this patch), and I don't see how we could get
next_run < now based on how next_run is computed in
ovpn_peer_keepalive_work_single (next_run1/next_run2 is always set to
now + X or something that we just tested to be > now).
Am I missing something?
> schedule_delayed_work(&ovpn->keepalive_work,
> - (next_run - now) * HZ);
> + delta * HZ > 0 ? delta * HZ : 0);
> }
> unlock_ovpn(ovpn, &release_list);
> }
--
Sabrina
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 19/24] ovpn: implement peer add/get/dump/delete via netlink
2025-03-04 14:35 ` Sabrina Dubroca
@ 2025-03-04 21:42 ` Antonio Quartulli
0 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 21:42 UTC (permalink / raw)
To: Sabrina Dubroca
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
On 04/03/2025 15:35, Sabrina Dubroca wrote:
> 2025-03-04, 01:33:49 +0100, Antonio Quartulli wrote:
>> @@ -1317,11 +1336,16 @@ void ovpn_peer_keepalive_work(struct work_struct *work)
>>
>> /* prevent rearming if the interface is being destroyed */
>> if (next_run > 0 && ovpn->registered) {
>> + time64_t delta = next_run - now;
>> +
>> netdev_dbg(ovpn->dev,
>> "scheduling keepalive work: now=%llu next_run=%llu delta=%llu\n",
>> - next_run, now, next_run - now);
>> + next_run, now, delta > 0 ? delta : 0);
>> + /* due to the waiting above, the next_run deadline may have
>> + * passed: in this case we reschedule the worker immediately
>> + */
>
> I don't understand this bit. I don't see what waiting you're refering
> to (in particular within this patch), and I don't see how we could get
> next_run < now based on how next_run is computed in
> ovpn_peer_keepalive_work_single (next_run1/next_run2 is always set to
> now + X or something that we just tested to be > now).
>
> Am I missing something?
Sorry - this is just noise.
Before getting to this final solution, I went for an intermediate
implementation where I was calling wait_for_completion() on a list of
removed peers (this is "the waiting above" the comment refers to).
Since I had no clue how long I waited, I had to update 'now'.
But at that point there was a chance that we had passed the deadline for
the next run, hence ending up with a negative delta.
This said, all this logic was thrown away, but I accidentally kept the
check on delta (that I even argued about in a previous email when you
saw the bogus ternary-op)
so yeah, the ternary-op can go away.
Thanks for double/triple checking with me.
Cheers,
>
>> schedule_delayed_work(&ovpn->keepalive_work,
>> - (next_run - now) * HZ);
>> + delta * HZ > 0 ? delta * HZ : 0);
>> }
>> unlock_ovpn(ovpn, &release_list);
>> }
>
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 46+ messages in thread
* [PATCH v21 20/24] ovpn: implement key add/get/del/swap via netlink
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (18 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 19/24] ovpn: implement peer add/get/dump/delete via netlink Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 12:00 ` Sabrina Dubroca
2025-03-04 0:33 ` [PATCH v21 21/24] ovpn: kill key and notify userspace in case of IV exhaustion Antonio Quartulli
` (3 subsequent siblings)
23 siblings, 1 reply; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
This change introduces the netlink commands needed to add, get, delete
and swap keys for a specific peer.
Userspace is expected to use these commands to create, inspect (non
sensitive data only), destroy and rotate session keys for a specific
peer.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/crypto.c | 40 ++++++
drivers/net/ovpn/crypto.h | 4 +
drivers/net/ovpn/crypto_aead.c | 17 +++
drivers/net/ovpn/crypto_aead.h | 2 +
drivers/net/ovpn/netlink.c | 301 ++++++++++++++++++++++++++++++++++++++++-
5 files changed, 360 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ovpn/crypto.c b/drivers/net/ovpn/crypto.c
index ac15aaa9844083328020fcc5ea6866e08ecbc184..f30c59c1193a167d7f420d89b665e2e61c57d81c 100644
--- a/drivers/net/ovpn/crypto.c
+++ b/drivers/net/ovpn/crypto.c
@@ -150,3 +150,43 @@ void ovpn_crypto_key_slots_swap(struct ovpn_crypto_state *cs)
spin_unlock_bh(&cs->lock);
}
+
+/**
+ * ovpn_crypto_config_get - populate keyconf object with non-sensible key data
+ * @cs: the crypto state to extract the key data from
+ * @slot: the specific slot to inspect
+ * @keyconf: the output object to populate
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+int ovpn_crypto_config_get(struct ovpn_crypto_state *cs,
+ enum ovpn_key_slot slot,
+ struct ovpn_key_config *keyconf)
+{
+ struct ovpn_crypto_key_slot *ks;
+ int idx;
+
+ switch (slot) {
+ case OVPN_KEY_SLOT_PRIMARY:
+ idx = cs->primary_idx;
+ break;
+ case OVPN_KEY_SLOT_SECONDARY:
+ idx = !cs->primary_idx;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ rcu_read_lock();
+ ks = rcu_dereference(cs->slots[idx]);
+ if (!ks) {
+ rcu_read_unlock();
+ return -ENOENT;
+ }
+
+ keyconf->cipher_alg = ovpn_aead_crypto_alg(ks);
+ keyconf->key_id = ks->key_id;
+ rcu_read_unlock();
+
+ return 0;
+}
diff --git a/drivers/net/ovpn/crypto.h b/drivers/net/ovpn/crypto.h
index f3b3be9866df910e3d68762377505f65c767a4fe..d6e888381c82d208c7ff619381858302ea6fbbc7 100644
--- a/drivers/net/ovpn/crypto.h
+++ b/drivers/net/ovpn/crypto.h
@@ -136,4 +136,8 @@ void ovpn_crypto_state_release(struct ovpn_crypto_state *cs);
void ovpn_crypto_key_slots_swap(struct ovpn_crypto_state *cs);
+int ovpn_crypto_config_get(struct ovpn_crypto_state *cs,
+ enum ovpn_key_slot slot,
+ struct ovpn_key_config *keyconf);
+
#endif /* _NET_OVPN_OVPNCRYPTO_H_ */
diff --git a/drivers/net/ovpn/crypto_aead.c b/drivers/net/ovpn/crypto_aead.c
index ac678f087451da66bc39148902db21045a94eb19..fe410b615d8442fb7e17364e2fa6c95b50162577 100644
--- a/drivers/net/ovpn/crypto_aead.c
+++ b/drivers/net/ovpn/crypto_aead.c
@@ -389,3 +389,20 @@ ovpn_aead_crypto_key_slot_new(const struct ovpn_key_config *kc)
ovpn_aead_crypto_key_slot_destroy(ks);
return ERR_PTR(ret);
}
+
+enum ovpn_cipher_alg ovpn_aead_crypto_alg(struct ovpn_crypto_key_slot *ks)
+{
+ const char *alg_name;
+
+ if (!ks->encrypt)
+ return OVPN_CIPHER_ALG_NONE;
+
+ alg_name = crypto_tfm_alg_name(crypto_aead_tfm(ks->encrypt));
+
+ if (!strcmp(alg_name, ALG_NAME_AES))
+ return OVPN_CIPHER_ALG_AES_GCM;
+ else if (!strcmp(alg_name, ALG_NAME_CHACHAPOLY))
+ return OVPN_CIPHER_ALG_CHACHA20_POLY1305;
+ else
+ return OVPN_CIPHER_ALG_NONE;
+}
diff --git a/drivers/net/ovpn/crypto_aead.h b/drivers/net/ovpn/crypto_aead.h
index 8a9d01f5eed700d2f7dfbbecbddbb370966682b9..d43aafa622315e3fd705e5da0f175356618a456d 100644
--- a/drivers/net/ovpn/crypto_aead.h
+++ b/drivers/net/ovpn/crypto_aead.h
@@ -28,4 +28,6 @@ struct ovpn_crypto_key_slot *
ovpn_aead_crypto_key_slot_new(const struct ovpn_key_config *kc);
void ovpn_aead_crypto_key_slot_destroy(struct ovpn_crypto_key_slot *ks);
+enum ovpn_cipher_alg ovpn_aead_crypto_alg(struct ovpn_crypto_key_slot *ks);
+
#endif /* _NET_OVPN_OVPNAEAD_H_ */
diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c
index 9824ce4437e63e602d37d31105fb9ac06f99d421..3d8b5e02e103e4177f3abacecfc4b52eb7226b87 100644
--- a/drivers/net/ovpn/netlink.c
+++ b/drivers/net/ovpn/netlink.c
@@ -17,6 +17,7 @@
#include "netlink.h"
#include "netlink-gen.h"
#include "bind.h"
+#include "crypto.h"
#include "peer.h"
#include "socket.h"
@@ -781,24 +782,316 @@ int ovpn_nl_peer_del_doit(struct sk_buff *skb, struct genl_info *info)
return ret;
}
+static int ovpn_nl_get_key_dir(struct genl_info *info, struct nlattr *key,
+ enum ovpn_cipher_alg cipher,
+ struct ovpn_key_direction *dir)
+{
+ struct nlattr *attrs[OVPN_A_KEYDIR_MAX + 1];
+ int ret;
+
+ ret = nla_parse_nested(attrs, OVPN_A_KEYDIR_MAX, key,
+ ovpn_keydir_nl_policy, info->extack);
+ if (ret)
+ return ret;
+
+ switch (cipher) {
+ case OVPN_CIPHER_ALG_AES_GCM:
+ case OVPN_CIPHER_ALG_CHACHA20_POLY1305:
+ if (NL_REQ_ATTR_CHECK(info->extack, key, attrs,
+ OVPN_A_KEYDIR_CIPHER_KEY) ||
+ NL_REQ_ATTR_CHECK(info->extack, key, attrs,
+ OVPN_A_KEYDIR_NONCE_TAIL))
+ return -EINVAL;
+
+ dir->cipher_key = nla_data(attrs[OVPN_A_KEYDIR_CIPHER_KEY]);
+ dir->cipher_key_size = nla_len(attrs[OVPN_A_KEYDIR_CIPHER_KEY]);
+
+ /* These algorithms require a 96bit nonce,
+ * Construct it by combining 4-bytes packet id and
+ * 8-bytes nonce-tail from userspace
+ */
+ dir->nonce_tail = nla_data(attrs[OVPN_A_KEYDIR_NONCE_TAIL]);
+ dir->nonce_tail_size = nla_len(attrs[OVPN_A_KEYDIR_NONCE_TAIL]);
+ break;
+ default:
+ NL_SET_ERR_MSG_MOD(info->extack, "unsupported cipher");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/**
+ * ovpn_nl_key_new_doit - configure a new key for the specified peer
+ * @skb: incoming netlink message
+ * @info: genetlink metadata
+ *
+ * This function allows the user to install a new key in the peer crypto
+ * state.
+ * Each peer has two 'slots', namely 'primary' and 'secondary', where
+ * keys can be installed. The key in the 'primary' slot is used for
+ * encryption, while both keys can be used for decryption by matching the
+ * key ID carried in the incoming packet.
+ *
+ * The user is responsible for rotating keys when necessary. The user
+ * may fetch peer traffic statistics via netlink in order to better
+ * identify the right time to rotate keys.
+ * The renegotiation follows these steps:
+ * 1. a new key is computed by the user and is installed in the 'secondary'
+ * slot
+ * 2. at user discretion (usually after a predetermined time) 'primary' and
+ * 'secondary' contents are swapped and the new key starts being used for
+ * encryption, while the old key is kept around for decryption of late
+ * packets.
+ *
+ * Return: 0 on success or a negative error code otherwise.
+ */
int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct nlattr *attrs[OVPN_A_KEYCONF_MAX + 1];
+ struct ovpn_priv *ovpn = info->user_ptr[0];
+ struct ovpn_peer_key_reset pkr;
+ struct ovpn_peer *peer;
+ u32 peer_id;
+ int ret;
+
+ if (GENL_REQ_ATTR_CHECK(info, OVPN_A_KEYCONF))
+ return -EINVAL;
+
+ ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX,
+ info->attrs[OVPN_A_KEYCONF],
+ ovpn_keyconf_nl_policy, info->extack);
+ if (ret)
+ return ret;
+
+ if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs,
+ OVPN_A_KEYCONF_PEER_ID))
+ return -EINVAL;
+
+ if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs,
+ OVPN_A_KEYCONF_SLOT) ||
+ NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs,
+ OVPN_A_KEYCONF_KEY_ID) ||
+ NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs,
+ OVPN_A_KEYCONF_CIPHER_ALG) ||
+ NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs,
+ OVPN_A_KEYCONF_ENCRYPT_DIR) ||
+ NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs,
+ OVPN_A_KEYCONF_DECRYPT_DIR))
+ return -EINVAL;
+
+ pkr.slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]);
+ pkr.key.key_id = nla_get_u16(attrs[OVPN_A_KEYCONF_KEY_ID]);
+ pkr.key.cipher_alg = nla_get_u16(attrs[OVPN_A_KEYCONF_CIPHER_ALG]);
+
+ ret = ovpn_nl_get_key_dir(info, attrs[OVPN_A_KEYCONF_ENCRYPT_DIR],
+ pkr.key.cipher_alg, &pkr.key.encrypt);
+ if (ret < 0)
+ return ret;
+
+ ret = ovpn_nl_get_key_dir(info, attrs[OVPN_A_KEYCONF_DECRYPT_DIR],
+ pkr.key.cipher_alg, &pkr.key.decrypt);
+ if (ret < 0)
+ return ret;
+
+ peer_id = nla_get_u32(attrs[OVPN_A_KEYCONF_PEER_ID]);
+ peer = ovpn_peer_get_by_id(ovpn, peer_id);
+ if (!peer) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "no peer with id %u to set key for",
+ peer_id);
+ return -ENOENT;
+ }
+
+ ret = ovpn_crypto_state_reset(&peer->crypto, &pkr);
+ if (ret < 0) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "cannot install new key for peer %u",
+ peer_id);
+ goto out;
+ }
+
+ netdev_dbg(ovpn->dev, "new key installed (id=%u) for peer %u\n",
+ pkr.key.key_id, peer_id);
+out:
+ ovpn_peer_put(peer);
+ return ret;
+}
+
+static int ovpn_nl_send_key(struct sk_buff *skb, const struct genl_info *info,
+ u32 peer_id, enum ovpn_key_slot slot,
+ const struct ovpn_key_config *keyconf)
+{
+ struct nlattr *attr;
+ void *hdr;
+
+ hdr = genlmsg_put(skb, info->snd_portid, info->snd_seq, &ovpn_nl_family,
+ 0, OVPN_CMD_KEY_GET);
+ if (!hdr)
+ return -ENOBUFS;
+
+ attr = nla_nest_start(skb, OVPN_A_KEYCONF);
+ if (!attr)
+ goto err;
+
+ if (nla_put_u32(skb, OVPN_A_KEYCONF_PEER_ID, peer_id))
+ goto err;
+
+ if (nla_put_u32(skb, OVPN_A_KEYCONF_SLOT, slot) ||
+ nla_put_u32(skb, OVPN_A_KEYCONF_KEY_ID, keyconf->key_id) ||
+ nla_put_u32(skb, OVPN_A_KEYCONF_CIPHER_ALG, keyconf->cipher_alg))
+ goto err;
+
+ nla_nest_end(skb, attr);
+ genlmsg_end(skb, hdr);
+
+ return 0;
+err:
+ genlmsg_cancel(skb, hdr);
+ return -EMSGSIZE;
}
int ovpn_nl_key_get_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct nlattr *attrs[OVPN_A_KEYCONF_MAX + 1];
+ struct ovpn_priv *ovpn = info->user_ptr[0];
+ struct ovpn_key_config keyconf = { 0 };
+ enum ovpn_key_slot slot;
+ struct ovpn_peer *peer;
+ struct sk_buff *msg;
+ u32 peer_id;
+ int ret;
+
+ if (GENL_REQ_ATTR_CHECK(info, OVPN_A_KEYCONF))
+ return -EINVAL;
+
+ ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX,
+ info->attrs[OVPN_A_KEYCONF],
+ ovpn_keyconf_nl_policy, info->extack);
+ if (ret)
+ return ret;
+
+ if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs,
+ OVPN_A_KEYCONF_PEER_ID))
+ return -EINVAL;
+
+ if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs,
+ OVPN_A_KEYCONF_SLOT))
+ return -EINVAL;
+
+ peer_id = nla_get_u32(attrs[OVPN_A_KEYCONF_PEER_ID]);
+ peer = ovpn_peer_get_by_id(ovpn, peer_id);
+ if (!peer) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "cannot find peer with id %u", peer_id);
+ return -ENOENT;
+ }
+
+ slot = nla_get_u32(attrs[OVPN_A_KEYCONF_SLOT]);
+
+ ret = ovpn_crypto_config_get(&peer->crypto, slot, &keyconf);
+ if (ret < 0) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "cannot extract key from slot %u for peer %u",
+ slot, peer_id);
+ goto err;
+ }
+
+ msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+ if (!msg) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ ret = ovpn_nl_send_key(msg, info, peer->id, slot, &keyconf);
+ if (ret < 0) {
+ nlmsg_free(msg);
+ goto err;
+ }
+
+ ret = genlmsg_reply(msg, info);
+err:
+ ovpn_peer_put(peer);
+ return ret;
}
int ovpn_nl_key_swap_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct ovpn_priv *ovpn = info->user_ptr[0];
+ struct nlattr *attrs[OVPN_A_PEER_MAX + 1];
+ struct ovpn_peer *peer;
+ u32 peer_id;
+ int ret;
+
+ if (GENL_REQ_ATTR_CHECK(info, OVPN_A_KEYCONF))
+ return -EINVAL;
+
+ ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX,
+ info->attrs[OVPN_A_KEYCONF],
+ ovpn_keyconf_nl_policy, info->extack);
+ if (ret)
+ return ret;
+
+ if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs,
+ OVPN_A_KEYCONF_PEER_ID))
+ return -EINVAL;
+
+ peer_id = nla_get_u32(attrs[OVPN_A_KEYCONF_PEER_ID]);
+ peer = ovpn_peer_get_by_id(ovpn, peer_id);
+ if (!peer) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "no peer with id %u to swap keys for",
+ peer_id);
+ return -ENOENT;
+ }
+
+ ovpn_crypto_key_slots_swap(&peer->crypto);
+ ovpn_peer_put(peer);
+
+ return 0;
}
int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct nlattr *attrs[OVPN_A_KEYCONF_MAX + 1];
+ struct ovpn_priv *ovpn = info->user_ptr[0];
+ enum ovpn_key_slot slot;
+ struct ovpn_peer *peer;
+ u32 peer_id;
+ int ret;
+
+ if (GENL_REQ_ATTR_CHECK(info, OVPN_A_KEYCONF))
+ return -EINVAL;
+
+ ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX,
+ info->attrs[OVPN_A_KEYCONF],
+ ovpn_keyconf_nl_policy, info->extack);
+ if (ret)
+ return ret;
+
+ if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs,
+ OVPN_A_KEYCONF_PEER_ID))
+ return -EINVAL;
+
+ if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_KEYCONF], attrs,
+ OVPN_A_KEYCONF_SLOT))
+ return -EINVAL;
+
+ peer_id = nla_get_u32(attrs[OVPN_A_KEYCONF_PEER_ID]);
+ slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]);
+
+ peer = ovpn_peer_get_by_id(ovpn, peer_id);
+ if (!peer) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "no peer with id %u to delete key for",
+ peer_id);
+ return -ENOENT;
+ }
+
+ ovpn_crypto_key_slot_delete(&peer->crypto, slot);
+ ovpn_peer_put(peer);
+
+ return 0;
}
/**
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* Re: [PATCH v21 20/24] ovpn: implement key add/get/del/swap via netlink
2025-03-04 0:33 ` [PATCH v21 20/24] ovpn: implement key add/get/del/swap " Antonio Quartulli
@ 2025-03-04 12:00 ` Sabrina Dubroca
2025-03-04 12:11 ` Antonio Quartulli
0 siblings, 1 reply; 46+ messages in thread
From: Sabrina Dubroca @ 2025-03-04 12:00 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
2025-03-04, 01:33:50 +0100, Antonio Quartulli wrote:
> int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info)
> {
...
> + pkr.slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]);
> + pkr.key.key_id = nla_get_u16(attrs[OVPN_A_KEYCONF_KEY_ID]);
> + pkr.key.cipher_alg = nla_get_u16(attrs[OVPN_A_KEYCONF_CIPHER_ALG]);
[...]
> +static int ovpn_nl_send_key(struct sk_buff *skb, const struct genl_info *info,
> + u32 peer_id, enum ovpn_key_slot slot,
> + const struct ovpn_key_config *keyconf)
> +{
...
> + if (nla_put_u32(skb, OVPN_A_KEYCONF_SLOT, slot) ||
> + nla_put_u32(skb, OVPN_A_KEYCONF_KEY_ID, keyconf->key_id) ||
> + nla_put_u32(skb, OVPN_A_KEYCONF_CIPHER_ALG, keyconf->cipher_alg))
That's a bit inconsistent. nla_put_u32 matches the generated policy,
but the nla_get_u{8,16} don't (and nla_get_u16 also doesn't match "u8
key_id" it's getting stored into).
[also kind of curious that the policy/spec uses U32 with max values of 1/2/7]
> int ovpn_nl_key_get_doit(struct sk_buff *skb, struct genl_info *info)
> {
...
> + slot = nla_get_u32(attrs[OVPN_A_KEYCONF_SLOT]);
> int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info)
> {
...
> + slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]);
A few more inconsistencies:
* OVPN_A_IFNAME is defined in the uapi but never used (I guess
leftover from genl link creation)
* OVPN_A_PEER_DEL_REASON (u32 vs u8)
drivers/net/ovpn/netlink-gen.c:52: [OVPN_A_PEER_DEL_REASON] = NLA_POLICY_MAX(NLA_U32, 4),
drivers/net/ovpn/netlink.c:1131: if (nla_put_u8(msg, OVPN_A_PEER_DEL_REASON, peer->delete_reason))
* OVPN_A_PEER_LINK_TX_PACKETS/OVPN_A_PEER_LINK_RX_PACKETS (uint vs u32):
drivers/net/ovpn/netlink-gen.c-57- [OVPN_A_PEER_LINK_RX_BYTES] = { .type = NLA_UINT, },
drivers/net/ovpn/netlink-gen.c-58- [OVPN_A_PEER_LINK_TX_BYTES] = { .type = NLA_UINT, },
drivers/net/ovpn/netlink-gen.c-59- [OVPN_A_PEER_LINK_RX_PACKETS] = { .type = NLA_U32, },
drivers/net/ovpn/netlink-gen.c:60: [OVPN_A_PEER_LINK_TX_PACKETS] = { .type = NLA_U32, },
--
drivers/net/ovpn/netlink.c-618- /* link RX stats */
drivers/net/ovpn/netlink.c-619- nla_put_uint(skb, OVPN_A_PEER_LINK_RX_BYTES,
drivers/net/ovpn/netlink.c-620- atomic64_read(&peer->link_stats.rx.bytes)) ||
drivers/net/ovpn/netlink.c-621- nla_put_uint(skb, OVPN_A_PEER_LINK_RX_PACKETS,
drivers/net/ovpn/netlink.c-622- atomic64_read(&peer->link_stats.rx.packets)) ||
drivers/net/ovpn/netlink.c-623- /* link TX stats */
drivers/net/ovpn/netlink.c-624- nla_put_uint(skb, OVPN_A_PEER_LINK_TX_BYTES,
drivers/net/ovpn/netlink.c-625- atomic64_read(&peer->link_stats.tx.bytes)) ||
drivers/net/ovpn/netlink.c:626: nla_put_uint(skb, OVPN_A_PEER_LINK_TX_PACKETS,
drivers/net/ovpn/netlink.c-627- atomic64_read(&peer->link_stats.tx.packets)))
I guess all the stats should be UINT.
--
Sabrina
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 20/24] ovpn: implement key add/get/del/swap via netlink
2025-03-04 12:00 ` Sabrina Dubroca
@ 2025-03-04 12:11 ` Antonio Quartulli
2025-03-04 23:09 ` Sabrina Dubroca
0 siblings, 1 reply; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 12:11 UTC (permalink / raw)
To: Sabrina Dubroca
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
On 04/03/2025 13:00, Sabrina Dubroca wrote:
> 2025-03-04, 01:33:50 +0100, Antonio Quartulli wrote:
>> int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info)
>> {
> ...
>> + pkr.slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]);
>> + pkr.key.key_id = nla_get_u16(attrs[OVPN_A_KEYCONF_KEY_ID]);
>> + pkr.key.cipher_alg = nla_get_u16(attrs[OVPN_A_KEYCONF_CIPHER_ALG]);
>
>
> [...]
>> +static int ovpn_nl_send_key(struct sk_buff *skb, const struct genl_info *info,
>> + u32 peer_id, enum ovpn_key_slot slot,
>> + const struct ovpn_key_config *keyconf)
>> +{
> ...
>> + if (nla_put_u32(skb, OVPN_A_KEYCONF_SLOT, slot) ||
>> + nla_put_u32(skb, OVPN_A_KEYCONF_KEY_ID, keyconf->key_id) ||
>> + nla_put_u32(skb, OVPN_A_KEYCONF_CIPHER_ALG, keyconf->cipher_alg))
>
> That's a bit inconsistent. nla_put_u32 matches the generated policy,
> but the nla_get_u{8,16} don't (and nla_get_u16 also doesn't match "u8
> key_id" it's getting stored into).
>
> [also kind of curious that the policy/spec uses U32 with max values of 1/2/7]
From
https://www.kernel.org/doc/html/next/userspace-api/netlink/specs.html#fix-width-integer-types
"Note that types smaller than 32 bit should be avoided as using them
does not save any memory in Netlink messages (due to alignment)."
Hence I went for u32 attributes, although values stored into them are
much smaller.
>
>
>
>> int ovpn_nl_key_get_doit(struct sk_buff *skb, struct genl_info *info)
>> {
> ...
>> + slot = nla_get_u32(attrs[OVPN_A_KEYCONF_SLOT]);
>
>
>
>> int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info)
>> {
> ...
>> + slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]);
Right. Since actual values are smaller I sometimes used the smaller macro.
I guess I better convert them all to u32.
>
>
>
> A few more inconsistencies:
>
> * OVPN_A_IFNAME is defined in the uapi but never used (I guess
> leftover from genl link creation)
Ouch, I guess you're right about it being a leftover.
>
> * OVPN_A_PEER_DEL_REASON (u32 vs u8)
> drivers/net/ovpn/netlink-gen.c:52: [OVPN_A_PEER_DEL_REASON] = NLA_POLICY_MAX(NLA_U32, 4),
> drivers/net/ovpn/netlink.c:1131: if (nla_put_u8(msg, OVPN_A_PEER_DEL_REASON, peer->delete_reason))
Like above, probably better to convert them all to u32.
>
> * OVPN_A_PEER_LINK_TX_PACKETS/OVPN_A_PEER_LINK_RX_PACKETS (uint vs u32):
> drivers/net/ovpn/netlink-gen.c-57- [OVPN_A_PEER_LINK_RX_BYTES] = { .type = NLA_UINT, },
> drivers/net/ovpn/netlink-gen.c-58- [OVPN_A_PEER_LINK_TX_BYTES] = { .type = NLA_UINT, },
> drivers/net/ovpn/netlink-gen.c-59- [OVPN_A_PEER_LINK_RX_PACKETS] = { .type = NLA_U32, },
> drivers/net/ovpn/netlink-gen.c:60: [OVPN_A_PEER_LINK_TX_PACKETS] = { .type = NLA_U32, },
> --
> drivers/net/ovpn/netlink.c-618- /* link RX stats */
> drivers/net/ovpn/netlink.c-619- nla_put_uint(skb, OVPN_A_PEER_LINK_RX_BYTES,
> drivers/net/ovpn/netlink.c-620- atomic64_read(&peer->link_stats.rx.bytes)) ||
> drivers/net/ovpn/netlink.c-621- nla_put_uint(skb, OVPN_A_PEER_LINK_RX_PACKETS,
> drivers/net/ovpn/netlink.c-622- atomic64_read(&peer->link_stats.rx.packets)) ||
> drivers/net/ovpn/netlink.c-623- /* link TX stats */
> drivers/net/ovpn/netlink.c-624- nla_put_uint(skb, OVPN_A_PEER_LINK_TX_BYTES,
> drivers/net/ovpn/netlink.c-625- atomic64_read(&peer->link_stats.tx.bytes)) ||
> drivers/net/ovpn/netlink.c:626: nla_put_uint(skb, OVPN_A_PEER_LINK_TX_PACKETS,
> drivers/net/ovpn/netlink.c-627- atomic64_read(&peer->link_stats.tx.packets)))
>
> I guess all the stats should be UINT.
u32 should be enough for packets - but yeah, going UINT is better as I
don't need to care if it really fits 4B or not.
Will do.
Thanks!
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 20/24] ovpn: implement key add/get/del/swap via netlink
2025-03-04 12:11 ` Antonio Quartulli
@ 2025-03-04 23:09 ` Sabrina Dubroca
2025-03-05 1:00 ` Antonio Quartulli
0 siblings, 1 reply; 46+ messages in thread
From: Sabrina Dubroca @ 2025-03-04 23:09 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
2025-03-04, 13:11:28 +0100, Antonio Quartulli wrote:
> On 04/03/2025 13:00, Sabrina Dubroca wrote:
> > 2025-03-04, 01:33:50 +0100, Antonio Quartulli wrote:
> > > int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info)
> > > {
> > ...
> > > + pkr.slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]);
> > > + pkr.key.key_id = nla_get_u16(attrs[OVPN_A_KEYCONF_KEY_ID]);
> > > + pkr.key.cipher_alg = nla_get_u16(attrs[OVPN_A_KEYCONF_CIPHER_ALG]);
> >
> >
> > [...]
> > > +static int ovpn_nl_send_key(struct sk_buff *skb, const struct genl_info *info,
> > > + u32 peer_id, enum ovpn_key_slot slot,
> > > + const struct ovpn_key_config *keyconf)
> > > +{
> > ...
> > > + if (nla_put_u32(skb, OVPN_A_KEYCONF_SLOT, slot) ||
> > > + nla_put_u32(skb, OVPN_A_KEYCONF_KEY_ID, keyconf->key_id) ||
> > > + nla_put_u32(skb, OVPN_A_KEYCONF_CIPHER_ALG, keyconf->cipher_alg))
> >
> > That's a bit inconsistent. nla_put_u32 matches the generated policy,
> > but the nla_get_u{8,16} don't (and nla_get_u16 also doesn't match "u8
> > key_id" it's getting stored into).
> >
> > [also kind of curious that the policy/spec uses U32 with max values of 1/2/7]
>
> From https://www.kernel.org/doc/html/next/userspace-api/netlink/specs.html#fix-width-integer-types
>
> "Note that types smaller than 32 bit should be avoided as using them does
> not save any memory in Netlink messages (due to alignment)."
>
> Hence I went for u32 attributes, although values stored into them are much
> smaller.
Right.
> > > int ovpn_nl_key_get_doit(struct sk_buff *skb, struct genl_info *info)
> > > {
> > ...
> > > + slot = nla_get_u32(attrs[OVPN_A_KEYCONF_SLOT]);
> >
> >
> >
> > > int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info)
> > > {
> > ...
> > > + slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]);
>
> Right. Since actual values are smaller I sometimes used the smaller macro.
Which only works on little-endian if the other side is using the full
size?
LE BE
put_u32(1) -> 01000000 00000001
get_u8 ^^ ^^
=1 =0
(and put_u8(1) vs get_u32 would result in fetching 0x1000000 in BE)
> I guess I better convert them all to u32.
SGTM
> > A few more inconsistencies:
> >
> > * OVPN_A_IFNAME is defined in the uapi but never used (I guess
> > leftover from genl link creation)
>
> Ouch, I guess you're right about it being a leftover.
>
> >
> > * OVPN_A_PEER_DEL_REASON (u32 vs u8)
> > drivers/net/ovpn/netlink-gen.c:52: [OVPN_A_PEER_DEL_REASON] = NLA_POLICY_MAX(NLA_U32, 4),
> > drivers/net/ovpn/netlink.c:1131: if (nla_put_u8(msg, OVPN_A_PEER_DEL_REASON, peer->delete_reason))
>
> Like above, probably better to convert them all to u32.
[...]
>
> u32 should be enough for packets - but yeah, going UINT is better as I don't
> need to care if it really fits 4B or not.
And that SGTM too. Thanks.
--
Sabrina
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 20/24] ovpn: implement key add/get/del/swap via netlink
2025-03-04 23:09 ` Sabrina Dubroca
@ 2025-03-05 1:00 ` Antonio Quartulli
2025-03-05 10:11 ` Sabrina Dubroca
0 siblings, 1 reply; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-05 1:00 UTC (permalink / raw)
To: Sabrina Dubroca
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
On 05/03/2025 00:09, Sabrina Dubroca wrote:
> 2025-03-04, 13:11:28 +0100, Antonio Quartulli wrote:
>> On 04/03/2025 13:00, Sabrina Dubroca wrote:
>>> 2025-03-04, 01:33:50 +0100, Antonio Quartulli wrote:
>>>> int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info)
>>>> {
>>> ...
>>>> + pkr.slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]);
>>>> + pkr.key.key_id = nla_get_u16(attrs[OVPN_A_KEYCONF_KEY_ID]);
>>>> + pkr.key.cipher_alg = nla_get_u16(attrs[OVPN_A_KEYCONF_CIPHER_ALG]);
>>>
>>>
>>> [...]
>>>> +static int ovpn_nl_send_key(struct sk_buff *skb, const struct genl_info *info,
>>>> + u32 peer_id, enum ovpn_key_slot slot,
>>>> + const struct ovpn_key_config *keyconf)
>>>> +{
>>> ...
>>>> + if (nla_put_u32(skb, OVPN_A_KEYCONF_SLOT, slot) ||
>>>> + nla_put_u32(skb, OVPN_A_KEYCONF_KEY_ID, keyconf->key_id) ||
>>>> + nla_put_u32(skb, OVPN_A_KEYCONF_CIPHER_ALG, keyconf->cipher_alg))
>>>
>>> That's a bit inconsistent. nla_put_u32 matches the generated policy,
>>> but the nla_get_u{8,16} don't (and nla_get_u16 also doesn't match "u8
>>> key_id" it's getting stored into).
>>>
>>> [also kind of curious that the policy/spec uses U32 with max values of 1/2/7]
>>
>> From https://www.kernel.org/doc/html/next/userspace-api/netlink/specs.html#fix-width-integer-types
>>
>> "Note that types smaller than 32 bit should be avoided as using them does
>> not save any memory in Netlink messages (due to alignment)."
>>
>> Hence I went for u32 attributes, although values stored into them are much
>> smaller.
>
> Right.
What's wrong with key_id being u8 tough?
I am a bit reluctant to change all key_id fields/variables to u32, just
because the netlink APIs prefers using u32 instead of u8.
Keeping variables/fields u8 allows to understand what values we're going
to store internally.
And thanks to the netlink policy we know that no larger value will be
attempted to be saved, even if the field is actually u32.
Cheers,
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 20/24] ovpn: implement key add/get/del/swap via netlink
2025-03-05 1:00 ` Antonio Quartulli
@ 2025-03-05 10:11 ` Sabrina Dubroca
2025-03-05 13:17 ` Antonio Quartulli
0 siblings, 1 reply; 46+ messages in thread
From: Sabrina Dubroca @ 2025-03-05 10:11 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
2025-03-05, 02:00:21 +0100, Antonio Quartulli wrote:
> On 05/03/2025 00:09, Sabrina Dubroca wrote:
> > 2025-03-04, 13:11:28 +0100, Antonio Quartulli wrote:
> > > On 04/03/2025 13:00, Sabrina Dubroca wrote:
> > > > 2025-03-04, 01:33:50 +0100, Antonio Quartulli wrote:
> > > > > int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info)
> > > > > {
> > > > ...
> > > > > + pkr.slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]);
> > > > > + pkr.key.key_id = nla_get_u16(attrs[OVPN_A_KEYCONF_KEY_ID]);
> > > > > + pkr.key.cipher_alg = nla_get_u16(attrs[OVPN_A_KEYCONF_CIPHER_ALG]);
> > > >
> > > >
> > > > [...]
> > > > > +static int ovpn_nl_send_key(struct sk_buff *skb, const struct genl_info *info,
> > > > > + u32 peer_id, enum ovpn_key_slot slot,
> > > > > + const struct ovpn_key_config *keyconf)
> > > > > +{
> > > > ...
> > > > > + if (nla_put_u32(skb, OVPN_A_KEYCONF_SLOT, slot) ||
> > > > > + nla_put_u32(skb, OVPN_A_KEYCONF_KEY_ID, keyconf->key_id) ||
> > > > > + nla_put_u32(skb, OVPN_A_KEYCONF_CIPHER_ALG, keyconf->cipher_alg))
> > > >
> > > > That's a bit inconsistent. nla_put_u32 matches the generated policy,
> > > > but the nla_get_u{8,16} don't (and nla_get_u16 also doesn't match "u8
> > > > key_id" it's getting stored into).
> > > >
> > > > [also kind of curious that the policy/spec uses U32 with max values of 1/2/7]
> > >
> > > From https://www.kernel.org/doc/html/next/userspace-api/netlink/specs.html#fix-width-integer-types
> > >
> > > "Note that types smaller than 32 bit should be avoided as using them does
> > > not save any memory in Netlink messages (due to alignment)."
> > >
> > > Hence I went for u32 attributes, although values stored into them are much
> > > smaller.
> >
> > Right.
>
> What's wrong with key_id being u8 tough?
Nothing. It would make a little bit more sense to use nla_get_u16 if
key_id was u16 (even with OVPN_A_KEYCONF_KEY_ID defined as U32), or to
use nla_get_u8 for u8, but here it was just 3 different int sizes and
that triggered my "uh? what?" :)
> I am a bit reluctant to change all key_id fields/variables to u32, just
> because the netlink APIs prefers using u32 instead of u8.
>
> Keeping variables/fields u8 allows to understand what values we're going to
> store internally.
Sure.
> And thanks to the netlink policy we know that no larger value will be
> attempted to be saved, even if the field is actually u32.
Yes.
--
Sabrina
^ permalink raw reply [flat|nested] 46+ messages in thread* Re: [PATCH v21 20/24] ovpn: implement key add/get/del/swap via netlink
2025-03-05 10:11 ` Sabrina Dubroca
@ 2025-03-05 13:17 ` Antonio Quartulli
0 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-05 13:17 UTC (permalink / raw)
To: Sabrina Dubroca
Cc: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Shuah Khan, ryazanov.s.a, Andrew Lunn, Simon Horman, linux-kernel,
linux-kselftest, Xiao Liang
On 05/03/2025 11:11, Sabrina Dubroca wrote:
> 2025-03-05, 02:00:21 +0100, Antonio Quartulli wrote:
>> On 05/03/2025 00:09, Sabrina Dubroca wrote:
>>> 2025-03-04, 13:11:28 +0100, Antonio Quartulli wrote:
>>>> On 04/03/2025 13:00, Sabrina Dubroca wrote:
>>>>> 2025-03-04, 01:33:50 +0100, Antonio Quartulli wrote:
>>>>>> int ovpn_nl_key_new_doit(struct sk_buff *skb, struct genl_info *info)
>>>>>> {
>>>>> ...
>>>>>> + pkr.slot = nla_get_u8(attrs[OVPN_A_KEYCONF_SLOT]);
>>>>>> + pkr.key.key_id = nla_get_u16(attrs[OVPN_A_KEYCONF_KEY_ID]);
>>>>>> + pkr.key.cipher_alg = nla_get_u16(attrs[OVPN_A_KEYCONF_CIPHER_ALG]);
>>>>>
>>>>>
>>>>> [...]
>>>>>> +static int ovpn_nl_send_key(struct sk_buff *skb, const struct genl_info *info,
>>>>>> + u32 peer_id, enum ovpn_key_slot slot,
>>>>>> + const struct ovpn_key_config *keyconf)
>>>>>> +{
>>>>> ...
>>>>>> + if (nla_put_u32(skb, OVPN_A_KEYCONF_SLOT, slot) ||
>>>>>> + nla_put_u32(skb, OVPN_A_KEYCONF_KEY_ID, keyconf->key_id) ||
>>>>>> + nla_put_u32(skb, OVPN_A_KEYCONF_CIPHER_ALG, keyconf->cipher_alg))
>>>>>
>>>>> That's a bit inconsistent. nla_put_u32 matches the generated policy,
>>>>> but the nla_get_u{8,16} don't (and nla_get_u16 also doesn't match "u8
>>>>> key_id" it's getting stored into).
>>>>>
>>>>> [also kind of curious that the policy/spec uses U32 with max values of 1/2/7]
>>>>
>>>> From https://www.kernel.org/doc/html/next/userspace-api/netlink/specs.html#fix-width-integer-types
>>>>
>>>> "Note that types smaller than 32 bit should be avoided as using them does
>>>> not save any memory in Netlink messages (due to alignment)."
>>>>
>>>> Hence I went for u32 attributes, although values stored into them are much
>>>> smaller.
>>>
>>> Right.
>>
>> What's wrong with key_id being u8 tough?
>
> Nothing. It would make a little bit more sense to use nla_get_u16 if
> key_id was u16 (even with OVPN_A_KEYCONF_KEY_ID defined as U32), or to
> use nla_get_u8 for u8, but here it was just 3 different int sizes and
> that triggered my "uh? what?" :)
>
>> I am a bit reluctant to change all key_id fields/variables to u32, just
>> because the netlink APIs prefers using u32 instead of u8.
>>
>> Keeping variables/fields u8 allows to understand what values we're going to
>> store internally.
>
> Sure.
>
>> And thanks to the netlink policy we know that no larger value will be
>> attempted to be saved, even if the field is actually u32.
>
> Yes.
>
Ok :)
Then I'll make sure they all use nla_get/put_u32, but will still store
the key_id in a u8 field.
Cheers!
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 46+ messages in thread
* [PATCH v21 21/24] ovpn: kill key and notify userspace in case of IV exhaustion
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (19 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 20/24] ovpn: implement key add/get/del/swap " Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 22/24] ovpn: notify userspace when a peer is deleted Antonio Quartulli
` (2 subsequent siblings)
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
IV wrap-around is cryptographically dangerous for a number of ciphers,
therefore kill the key and inform userspace (via netlink) should the
IV space go exhausted.
Userspace has two ways of deciding when the key has to be renewed before
exhausting the IV space:
1) time based approach:
after X seconds/minutes userspace generates a new key and sends it
to the kernel. This is based on guestimate and normally default
timer value works well.
2) packet count based approach:
after X packets/bytes userspace generates a new key and sends it to
the kernel. Userspace keeps track of the amount of traffic by
periodically polling GET_PEER and fetching the VPN/LINK stats.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/crypto.c | 19 ++++++++++++++
drivers/net/ovpn/crypto.h | 2 ++
drivers/net/ovpn/io.c | 13 ++++++++++
drivers/net/ovpn/netlink.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/netlink.h | 2 ++
5 files changed, 100 insertions(+)
diff --git a/drivers/net/ovpn/crypto.c b/drivers/net/ovpn/crypto.c
index f30c59c1193a167d7f420d89b665e2e61c57d81c..b86340e51e0cafe2931221ce91a0f7a977e5a047 100644
--- a/drivers/net/ovpn/crypto.c
+++ b/drivers/net/ovpn/crypto.c
@@ -54,6 +54,25 @@ void ovpn_crypto_state_release(struct ovpn_crypto_state *cs)
}
}
+/* removes the key matching the specified id from the crypto context */
+void ovpn_crypto_kill_key(struct ovpn_crypto_state *cs, u8 key_id)
+{
+ struct ovpn_crypto_key_slot *ks = NULL;
+
+ spin_lock_bh(&cs->lock);
+ if (rcu_access_pointer(cs->slots[0])->key_id == key_id) {
+ ks = rcu_replace_pointer(cs->slots[0], NULL,
+ lockdep_is_held(&cs->lock));
+ } else if (rcu_access_pointer(cs->slots[1])->key_id == key_id) {
+ ks = rcu_replace_pointer(cs->slots[1], NULL,
+ lockdep_is_held(&cs->lock));
+ }
+ spin_unlock_bh(&cs->lock);
+
+ if (ks)
+ ovpn_crypto_key_slot_put(ks);
+}
+
/* Reset the ovpn_crypto_state object in a way that is atomic
* to RCU readers.
*/
diff --git a/drivers/net/ovpn/crypto.h b/drivers/net/ovpn/crypto.h
index d6e888381c82d208c7ff619381858302ea6fbbc7..7c88927830020482ca4d357ac44d3b4916db0891 100644
--- a/drivers/net/ovpn/crypto.h
+++ b/drivers/net/ovpn/crypto.h
@@ -140,4 +140,6 @@ int ovpn_crypto_config_get(struct ovpn_crypto_state *cs,
enum ovpn_key_slot slot,
struct ovpn_key_config *keyconf);
+void ovpn_crypto_kill_key(struct ovpn_crypto_state *cs, u8 key_id);
+
#endif /* _NET_OVPN_OVPNCRYPTO_H_ */
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index 5b673eae255033b9d7d6e7890a46686403d7c222..d81c1a2a958c73e22e548d8e63fc78821b5eb881 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -255,6 +255,19 @@ void ovpn_encrypt_post(void *data, int ret)
if (likely(ovpn_skb_cb(skb)->req))
aead_request_free(ovpn_skb_cb(skb)->req);
+ if (unlikely(ret == -ERANGE)) {
+ /* we ran out of IVs and we must kill the key as it can't be
+ * use anymore
+ */
+ netdev_warn(peer->ovpn->dev,
+ "killing key %u for peer %u\n", ks->key_id,
+ peer->id);
+ ovpn_crypto_kill_key(&peer->crypto, ks->key_id);
+ /* let userspace know so that a new key must be negotiated */
+ ovpn_nl_key_swap_notify(peer, ks->key_id);
+ goto err;
+ }
+
if (unlikely(ret < 0))
goto err;
diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c
index 3d8b5e02e103e4177f3abacecfc4b52eb7226b87..d1845c1b446c82111ae349092e779fd46824c83a 100644
--- a/drivers/net/ovpn/netlink.c
+++ b/drivers/net/ovpn/netlink.c
@@ -1094,6 +1094,70 @@ int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info)
return 0;
}
+/**
+ * ovpn_nl_key_swap_notify - notify userspace peer's key must be renewed
+ * @peer: the peer whose key needs to be renewed
+ * @key_id: the ID of the key that needs to be renewed
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+int ovpn_nl_key_swap_notify(struct ovpn_peer *peer, u8 key_id)
+{
+ struct ovpn_socket *sock;
+ struct nlattr *k_attr;
+ struct sk_buff *msg;
+ int ret = -EMSGSIZE;
+ void *hdr;
+
+ netdev_info(peer->ovpn->dev, "peer with id %u must rekey - primary key unusable.\n",
+ peer->id);
+
+ msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
+ if (!msg)
+ return -ENOMEM;
+
+ hdr = genlmsg_put(msg, 0, 0, &ovpn_nl_family, 0, OVPN_CMD_KEY_SWAP_NTF);
+ if (!hdr) {
+ ret = -ENOBUFS;
+ goto err_free_msg;
+ }
+
+ if (nla_put_u32(msg, OVPN_A_IFINDEX, peer->ovpn->dev->ifindex))
+ goto err_cancel_msg;
+
+ k_attr = nla_nest_start(msg, OVPN_A_KEYCONF);
+ if (!k_attr)
+ goto err_cancel_msg;
+
+ if (nla_put_u32(msg, OVPN_A_KEYCONF_PEER_ID, peer->id))
+ goto err_cancel_msg;
+
+ if (nla_put_u16(msg, OVPN_A_KEYCONF_KEY_ID, key_id))
+ goto err_cancel_msg;
+
+ nla_nest_end(msg, k_attr);
+ genlmsg_end(msg, hdr);
+
+ rcu_read_lock();
+ sock = rcu_dereference(peer->sock);
+ if (!sock) {
+ ret = -EINVAL;
+ goto err_unlock;
+ }
+ genlmsg_multicast_netns(&ovpn_nl_family, sock_net(sock->sock->sk),
+ msg, 0, OVPN_NLGRP_PEERS, GFP_ATOMIC);
+ rcu_read_unlock();
+
+ return 0;
+err_unlock:
+ rcu_read_unlock();
+err_cancel_msg:
+ genlmsg_cancel(msg, hdr);
+err_free_msg:
+ nlmsg_free(msg);
+ return ret;
+}
+
/**
* ovpn_nl_register - perform any needed registration in the NL subsustem
*
diff --git a/drivers/net/ovpn/netlink.h b/drivers/net/ovpn/netlink.h
index 0d6c34e17082cc7c52dd9c5d5ed1e964925b3f4b..5dc84c8e5e803014053faa0d892fc3a7259d40e5 100644
--- a/drivers/net/ovpn/netlink.h
+++ b/drivers/net/ovpn/netlink.h
@@ -12,4 +12,6 @@
int ovpn_nl_register(void);
void ovpn_nl_unregister(void);
+int ovpn_nl_key_swap_notify(struct ovpn_peer *peer, u8 key_id);
+
#endif /* _NET_OVPN_NETLINK_H_ */
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 22/24] ovpn: notify userspace when a peer is deleted
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (20 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 21/24] ovpn: kill key and notify userspace in case of IV exhaustion Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 23/24] ovpn: add basic ethtool support Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 24/24] testing/selftests: add test tool and scripts for ovpn module Antonio Quartulli
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang
Whenever a peer is deleted, send a notification to userspace so that it
can react accordingly.
This is most important when a peer is deleted due to ping timeout,
because it all happens in kernelspace and thus userspace has no direct
way to learn about it.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/netlink.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/netlink.h | 1 +
drivers/net/ovpn/peer.c | 1 +
3 files changed, 67 insertions(+)
diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c
index d1845c1b446c82111ae349092e779fd46824c83a..5e08decc961fae1d26065098d64d59cbac70fbc0 100644
--- a/drivers/net/ovpn/netlink.c
+++ b/drivers/net/ovpn/netlink.c
@@ -1094,6 +1094,71 @@ int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info)
return 0;
}
+/**
+ * ovpn_nl_peer_del_notify - notify userspace about peer being deleted
+ * @peer: the peer being deleted
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+int ovpn_nl_peer_del_notify(struct ovpn_peer *peer)
+{
+ struct ovpn_socket *sock;
+ struct sk_buff *msg;
+ struct nlattr *attr;
+ int ret = -EMSGSIZE;
+ void *hdr;
+
+ netdev_info(peer->ovpn->dev, "deleting peer with id %u, reason %d\n",
+ peer->id, peer->delete_reason);
+
+ msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
+ if (!msg)
+ return -ENOMEM;
+
+ hdr = genlmsg_put(msg, 0, 0, &ovpn_nl_family, 0, OVPN_CMD_PEER_DEL_NTF);
+ if (!hdr) {
+ ret = -ENOBUFS;
+ goto err_free_msg;
+ }
+
+ if (nla_put_u32(msg, OVPN_A_IFINDEX, peer->ovpn->dev->ifindex))
+ goto err_cancel_msg;
+
+ attr = nla_nest_start(msg, OVPN_A_PEER);
+ if (!attr)
+ goto err_cancel_msg;
+
+ if (nla_put_u8(msg, OVPN_A_PEER_DEL_REASON, peer->delete_reason))
+ goto err_cancel_msg;
+
+ if (nla_put_u32(msg, OVPN_A_PEER_ID, peer->id))
+ goto err_cancel_msg;
+
+ nla_nest_end(msg, attr);
+
+ genlmsg_end(msg, hdr);
+
+ rcu_read_lock();
+ sock = rcu_dereference(peer->sock);
+ if (!sock) {
+ ret = -EINVAL;
+ goto err_unlock;
+ }
+ genlmsg_multicast_netns(&ovpn_nl_family, sock_net(sock->sock->sk),
+ msg, 0, OVPN_NLGRP_PEERS, GFP_ATOMIC);
+ rcu_read_unlock();
+
+ return 0;
+
+err_unlock:
+ rcu_read_unlock();
+err_cancel_msg:
+ genlmsg_cancel(msg, hdr);
+err_free_msg:
+ nlmsg_free(msg);
+ return ret;
+}
+
/**
* ovpn_nl_key_swap_notify - notify userspace peer's key must be renewed
* @peer: the peer whose key needs to be renewed
diff --git a/drivers/net/ovpn/netlink.h b/drivers/net/ovpn/netlink.h
index 5dc84c8e5e803014053faa0d892fc3a7259d40e5..8615dfc3c4720a2a550b5cd1a8454ccc58a3c6ba 100644
--- a/drivers/net/ovpn/netlink.h
+++ b/drivers/net/ovpn/netlink.h
@@ -12,6 +12,7 @@
int ovpn_nl_register(void);
void ovpn_nl_unregister(void);
+int ovpn_nl_peer_del_notify(struct ovpn_peer *peer);
int ovpn_nl_key_swap_notify(struct ovpn_peer *peer, u8 key_id);
#endif /* _NET_OVPN_NETLINK_H_ */
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 2a9f373b7a2f684203677bdc7b5a147c41ea2daf..f9216c0be42badae79b0077718416dfccb1fb987 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -689,6 +689,7 @@ static void ovpn_peer_remove(struct ovpn_peer *peer,
}
peer->delete_reason = reason;
+ ovpn_nl_peer_del_notify(peer);
/* append to provided list for later socket release and ref drop */
llist_add(&peer->release_entry, release_list);
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 23/24] ovpn: add basic ethtool support
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (21 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 22/24] ovpn: notify userspace when a peer is deleted Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
2025-03-04 0:33 ` [PATCH v21 24/24] testing/selftests: add test tool and scripts for ovpn module Antonio Quartulli
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang,
Andrew Lunn
Implement support for basic ethtool functionality.
Note that ovpn is a virtual device driver, therefore
various ethtool APIs are just not meaningful and thus
not implemented.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
---
drivers/net/ovpn/main.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index dd05d0fe7a2d139bda55ebd68b9e1d78f5c00af9..886601ddaf7bdee4761691d293274a61da204f2b 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -7,6 +7,7 @@
* James Yonan <james@openvpn.net>
*/
+#include <linux/ethtool.h>
#include <linux/genetlink.h>
#include <linux/module.h>
#include <linux/netdevice.h>
@@ -143,6 +144,19 @@ bool ovpn_dev_is_valid(const struct net_device *dev)
return dev->netdev_ops == &ovpn_netdev_ops;
}
+static void ovpn_get_drvinfo(struct net_device *dev,
+ struct ethtool_drvinfo *info)
+{
+ strscpy(info->driver, "ovpn", sizeof(info->driver));
+ strscpy(info->bus_info, "ovpn", sizeof(info->bus_info));
+}
+
+static const struct ethtool_ops ovpn_ethtool_ops = {
+ .get_drvinfo = ovpn_get_drvinfo,
+ .get_link = ethtool_op_get_link,
+ .get_ts_info = ethtool_op_get_ts_info,
+};
+
static void ovpn_setup(struct net_device *dev)
{
netdev_features_t feat = NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_RXCSUM |
@@ -153,6 +167,7 @@ static void ovpn_setup(struct net_device *dev)
dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
+ dev->ethtool_ops = &ovpn_ethtool_ops;
dev->netdev_ops = &ovpn_netdev_ops;
dev->priv_destructor = ovpn_priv_free;
--
2.45.3
^ permalink raw reply related [flat|nested] 46+ messages in thread* [PATCH v21 24/24] testing/selftests: add test tool and scripts for ovpn module
2025-03-04 0:33 [PATCH v21 00/24] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (22 preceding siblings ...)
2025-03-04 0:33 ` [PATCH v21 23/24] ovpn: add basic ethtool support Antonio Quartulli
@ 2025-03-04 0:33 ` Antonio Quartulli
23 siblings, 0 replies; 46+ messages in thread
From: Antonio Quartulli @ 2025-03-04 0:33 UTC (permalink / raw)
To: netdev, Eric Dumazet, Jakub Kicinski, Paolo Abeni, Donald Hunter,
Antonio Quartulli, Shuah Khan, sd, ryazanov.s.a, Andrew Lunn
Cc: Simon Horman, linux-kernel, linux-kselftest, Xiao Liang,
Shuah Khan
The ovpn-cli tool can be compiled and used as selftest for the ovpn
kernel module.
[NOTE: it depends on libmedtls for decoding base64-encoded keys]
ovpn-cli implements the netlink and RTNL APIs and can thus be integrated
in any script for more automated testing.
Along with the tool, a bunch of scripts are provided that perform basic
functionality tests by means of network namespaces.
These scripts take part to the kselftest automation.
The output of the scripts, which will appear in the kselftest
reports, is a list of steps performed by the scripts plus some
output coming from the execution of `ping`, `iperf` and `ovpn-cli`
itself.
In general it is useful only in case of failure, in order to
understand which step has failed and why.
Please note: since peer sockets are tied to the userspace
process that created them (i.e. exiting the process will result
in closing the socket), every run of ovpn-cli that created
one will go to background and enter pause(), waiting for the
signal which will allow it to terminate.
Termination is accomplished at the end of each script by
issuing a killall command.
Cc: linux-kselftest@vger.kernel.org
Cc: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
MAINTAINERS | 1 +
tools/testing/selftests/Makefile | 1 +
tools/testing/selftests/net/ovpn/.gitignore | 2 +
tools/testing/selftests/net/ovpn/Makefile | 31 +
tools/testing/selftests/net/ovpn/common.sh | 92 +
tools/testing/selftests/net/ovpn/config | 10 +
tools/testing/selftests/net/ovpn/data64.key | 5 +
tools/testing/selftests/net/ovpn/ovpn-cli.c | 2395 ++++++++++++++++++++
tools/testing/selftests/net/ovpn/tcp_peers.txt | 5 +
.../testing/selftests/net/ovpn/test-chachapoly.sh | 9 +
.../selftests/net/ovpn/test-close-socket-tcp.sh | 9 +
.../selftests/net/ovpn/test-close-socket.sh | 45 +
tools/testing/selftests/net/ovpn/test-float.sh | 9 +
tools/testing/selftests/net/ovpn/test-tcp.sh | 9 +
tools/testing/selftests/net/ovpn/test.sh | 113 +
tools/testing/selftests/net/ovpn/udp_peers.txt | 5 +
16 files changed, 2741 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 1dd979149a1ae5de7af996252ad3385643368667..ee4366eaa554ebeb9fa6252f492412abc7f52c2d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17758,6 +17758,7 @@ T: git https://github.com/OpenVPN/linux-kernel-ovpn.git
F: Documentation/netlink/specs/ovpn.yaml
F: drivers/net/ovpn/
F: include/uapi/linux/ovpn.h
+F: tools/testing/selftests/net/ovpn/
OPENVSWITCH
M: Pravin B Shelar <pshelar@ovn.org>
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index 8daac70c2f9d2c41be51f421b9c1e27eeee8bede..042be9a42b2e21cc5cb9536e0e7cb4089bcc7ca6 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -69,6 +69,7 @@ TARGETS += net/hsr
TARGETS += net/mptcp
TARGETS += net/netfilter
TARGETS += net/openvswitch
+TARGETS += net/ovpn
TARGETS += net/packetdrill
TARGETS += net/rds
TARGETS += net/tcp_ao
diff --git a/tools/testing/selftests/net/ovpn/.gitignore b/tools/testing/selftests/net/ovpn/.gitignore
new file mode 100644
index 0000000000000000000000000000000000000000..ee44c081ca7c089933659689303c303a9fa9713b
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0+
+ovpn-cli
diff --git a/tools/testing/selftests/net/ovpn/Makefile b/tools/testing/selftests/net/ovpn/Makefile
new file mode 100644
index 0000000000000000000000000000000000000000..2d102878cb6ddf3dc7ac8e183068633ec72e5b95
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/Makefile
@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2020-2025 OpenVPN, Inc.
+#
+CFLAGS = -pedantic -Wextra -Wall -Wl,--no-as-needed -g -O0 -ggdb $(KHDR_INCLUDES)
+VAR_CFLAGS = $(shell pkg-config --cflags libnl-3.0 libnl-genl-3.0 2>/dev/null)
+ifeq ($(VAR_CFLAGS),)
+VAR_CFLAGS = -I/usr/include/libnl3
+endif
+CFLAGS += $(VAR_CFLAGS)
+
+
+LDLIBS = -lmbedtls -lmbedcrypto
+VAR_LDLIBS = $(shell pkg-config --libs libnl-3.0 libnl-genl-3.0 2>/dev/null)
+ifeq ($(VAR_LDLIBS),)
+VAR_LDLIBS = -lnl-genl-3 -lnl-3
+endif
+LDLIBS += $(VAR_LDLIBS)
+
+
+TEST_FILES = common.sh
+
+TEST_PROGS = test.sh \
+ test-chachapoly.sh \
+ test-tcp.sh \
+ test-float.sh \
+ test-close-socket.sh \
+ test-close-socket-tcp.sh
+
+TEST_GEN_FILES := ovpn-cli
+
+include ../../lib.mk
diff --git a/tools/testing/selftests/net/ovpn/common.sh b/tools/testing/selftests/net/ovpn/common.sh
new file mode 100644
index 0000000000000000000000000000000000000000..7502292a1ee037f8ff433bd4b468595acf1a81b3
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/common.sh
@@ -0,0 +1,92 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2020-2025 OpenVPN, Inc.
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+
+UDP_PEERS_FILE=${UDP_PEERS_FILE:-udp_peers.txt}
+TCP_PEERS_FILE=${TCP_PEERS_FILE:-tcp_peers.txt}
+OVPN_CLI=${OVPN_CLI:-./ovpn-cli}
+ALG=${ALG:-aes}
+PROTO=${PROTO:-UDP}
+FLOAT=${FLOAT:-0}
+
+create_ns() {
+ ip netns add peer${1}
+}
+
+setup_ns() {
+ MODE="P2P"
+
+ if [ ${1} -eq 0 ]; then
+ MODE="MP"
+ for p in $(seq 1 ${NUM_PEERS}); do
+ ip link add veth${p} netns peer0 type veth peer name veth${p} netns peer${p}
+
+ ip -n peer0 addr add 10.10.${p}.1/24 dev veth${p}
+ ip -n peer0 link set veth${p} up
+
+ ip -n peer${p} addr add 10.10.${p}.2/24 dev veth${p}
+ ip -n peer${p} link set veth${p} up
+ done
+ fi
+
+ ip netns exec peer${1} ${OVPN_CLI} new_iface tun${1} $MODE
+ ip -n peer${1} addr add ${2} dev tun${1}
+ ip -n peer${1} link set tun${1} up
+}
+
+add_peer() {
+ if [ "${PROTO}" == "UDP" ]; then
+ if [ ${1} -eq 0 ]; then
+ ip netns exec peer0 ${OVPN_CLI} new_multi_peer tun0 1 ${UDP_PEERS_FILE}
+
+ for p in $(seq 1 ${NUM_PEERS}); do
+ ip netns exec peer0 ${OVPN_CLI} new_key tun0 ${p} 1 0 ${ALG} 0 \
+ data64.key
+ done
+ else
+ ip netns exec peer${1} ${OVPN_CLI} new_peer tun${1} ${1} 1 10.10.${1}.1 1
+ ip netns exec peer${1} ${OVPN_CLI} new_key tun${1} ${1} 1 0 ${ALG} 1 \
+ data64.key
+ fi
+ else
+ if [ ${1} -eq 0 ]; then
+ (ip netns exec peer0 ${OVPN_CLI} listen tun0 1 ${TCP_PEERS_FILE} && {
+ for p in $(seq 1 ${NUM_PEERS}); do
+ ip netns exec peer0 ${OVPN_CLI} new_key tun0 ${p} 1 0 \
+ ${ALG} 0 data64.key
+ done
+ }) &
+ sleep 5
+ else
+ ip netns exec peer${1} ${OVPN_CLI} connect tun${1} ${1} 10.10.${1}.1 1 \
+ data64.key
+ fi
+ fi
+}
+
+cleanup() {
+ # some ovpn-cli processes sleep in background so they need manual poking
+ killall $(basename ${OVPN_CLI}) 2>/dev/null || true
+
+ # netns peer0 is deleted without erasing ifaces first
+ for p in $(seq 1 10); do
+ ip -n peer${p} link set tun${p} down 2>/dev/null || true
+ ip netns exec peer${p} ${OVPN_CLI} del_iface tun${p} 2>/dev/null || true
+ done
+ for p in $(seq 1 10); do
+ ip -n peer0 link del veth${p} 2>/dev/null || true
+ done
+ for p in $(seq 0 10); do
+ ip netns del peer${p} 2>/dev/null || true
+ done
+}
+
+if [ "${PROTO}" == "UDP" ]; then
+ NUM_PEERS=${NUM_PEERS:-$(wc -l ${UDP_PEERS_FILE} | awk '{print $1}')}
+else
+ NUM_PEERS=${NUM_PEERS:-$(wc -l ${TCP_PEERS_FILE} | awk '{print $1}')}
+fi
+
+
diff --git a/tools/testing/selftests/net/ovpn/config b/tools/testing/selftests/net/ovpn/config
new file mode 100644
index 0000000000000000000000000000000000000000..71946ba9fa175c191725e369eb9b973503d9d9c4
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/config
@@ -0,0 +1,10 @@
+CONFIG_NET=y
+CONFIG_INET=y
+CONFIG_STREAM_PARSER=y
+CONFIG_NET_UDP_TUNNEL=y
+CONFIG_DST_CACHE=y
+CONFIG_CRYPTO=y
+CONFIG_CRYPTO_AES=y
+CONFIG_CRYPTO_GCM=y
+CONFIG_CRYPTO_CHACHA20POLY1305=y
+CONFIG_OVPN=m
diff --git a/tools/testing/selftests/net/ovpn/data64.key b/tools/testing/selftests/net/ovpn/data64.key
new file mode 100644
index 0000000000000000000000000000000000000000..a99e88c4e290f58b12f399b857b873f308d9ba09
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/data64.key
@@ -0,0 +1,5 @@
+jRqMACN7d7/aFQNT8S7jkrBD8uwrgHbG5OQZP2eu4R1Y7tfpS2bf5RHv06Vi163CGoaIiTX99R3B
+ia9ycAH8Wz1+9PWv51dnBLur9jbShlgZ2QHLtUc4a/gfT7zZwULXuuxdLnvR21DDeMBaTbkgbai9
+uvAa7ne1liIgGFzbv+Bas4HDVrygxIxuAnP5Qgc3648IJkZ0QEXPF+O9f0n5+QIvGCxkAUVx+5K6
+KIs+SoeWXnAopELmoGSjUpFtJbagXK82HfdqpuUxT2Tnuef0/14SzVE/vNleBNu2ZbyrSAaah8tE
+BofkPJUBFY+YQcfZNM5Dgrw3i+Bpmpq/gpdg5w==
diff --git a/tools/testing/selftests/net/ovpn/ovpn-cli.c b/tools/testing/selftests/net/ovpn/ovpn-cli.c
new file mode 100644
index 0000000000000000000000000000000000000000..b6948b23e6b7f2ea6565b85fffb4dae8a8d22c3d
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/ovpn-cli.c
@@ -0,0 +1,2395 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel accelerator
+ *
+ * Copyright (C) 2020-2025 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <stdio.h>
+#include <inttypes.h>
+#include <stdbool.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <arpa/inet.h>
+#include <net/if.h>
+#include <netinet/in.h>
+#include <time.h>
+
+#include <linux/ovpn.h>
+#include <linux/types.h>
+#include <linux/netlink.h>
+
+#include <netlink/socket.h>
+#include <netlink/netlink.h>
+#include <netlink/genl/genl.h>
+#include <netlink/genl/family.h>
+#include <netlink/genl/ctrl.h>
+
+#include <mbedtls/base64.h>
+#include <mbedtls/error.h>
+
+#include <sys/socket.h>
+
+/* defines to make checkpatch happy */
+#define strscpy strncpy
+#define __always_unused __attribute__((__unused__))
+
+/* libnl < 3.5.0 does not set the NLA_F_NESTED on its own, therefore we
+ * have to explicitly do it to prevent the kernel from failing upon
+ * parsing of the message
+ */
+#define nla_nest_start(_msg, _type) \
+ nla_nest_start(_msg, (_type) | NLA_F_NESTED)
+
+/* libnl < 3.11.0 does not implement nla_get_uint() */
+uint64_t ovpn_nla_get_uint(struct nlattr *attr)
+{
+ if (nla_len(attr) == sizeof(uint32_t))
+ return nla_get_u32(attr);
+ else
+ return nla_get_u64(attr);
+}
+
+typedef int (*ovpn_nl_cb)(struct nl_msg *msg, void *arg);
+
+enum ovpn_key_direction {
+ KEY_DIR_IN = 0,
+ KEY_DIR_OUT,
+};
+
+#define KEY_LEN (256 / 8)
+#define NONCE_LEN 8
+
+#define PEER_ID_UNDEF 0x00FFFFFF
+#define MAX_PEERS 10
+
+struct nl_ctx {
+ struct nl_sock *nl_sock;
+ struct nl_msg *nl_msg;
+ struct nl_cb *nl_cb;
+
+ int ovpn_dco_id;
+};
+
+enum ovpn_cmd {
+ CMD_INVALID,
+ CMD_NEW_IFACE,
+ CMD_DEL_IFACE,
+ CMD_LISTEN,
+ CMD_CONNECT,
+ CMD_NEW_PEER,
+ CMD_NEW_MULTI_PEER,
+ CMD_SET_PEER,
+ CMD_DEL_PEER,
+ CMD_GET_PEER,
+ CMD_NEW_KEY,
+ CMD_DEL_KEY,
+ CMD_GET_KEY,
+ CMD_SWAP_KEYS,
+ CMD_LISTEN_MCAST,
+};
+
+struct ovpn_ctx {
+ enum ovpn_cmd cmd;
+
+ __u8 key_enc[KEY_LEN];
+ __u8 key_dec[KEY_LEN];
+ __u8 nonce[NONCE_LEN];
+
+ enum ovpn_cipher_alg cipher;
+
+ sa_family_t sa_family;
+
+ unsigned long peer_id;
+ unsigned long lport;
+
+ union {
+ struct sockaddr_in in4;
+ struct sockaddr_in6 in6;
+ } remote;
+
+ union {
+ struct sockaddr_in in4;
+ struct sockaddr_in6 in6;
+ } peer_ip;
+
+ bool peer_ip_set;
+
+ unsigned int ifindex;
+ char ifname[IFNAMSIZ];
+ enum ovpn_mode mode;
+ bool mode_set;
+
+ int socket;
+ int cli_sockets[MAX_PEERS];
+
+ __u32 keepalive_interval;
+ __u32 keepalive_timeout;
+
+ enum ovpn_key_direction key_dir;
+ enum ovpn_key_slot key_slot;
+ int key_id;
+
+ const char *peers_file;
+};
+
+static int ovpn_nl_recvmsgs(struct nl_ctx *ctx)
+{
+ int ret;
+
+ ret = nl_recvmsgs(ctx->nl_sock, ctx->nl_cb);
+
+ switch (ret) {
+ case -NLE_INTR:
+ fprintf(stderr,
+ "netlink received interrupt due to signal - ignoring\n");
+ break;
+ case -NLE_NOMEM:
+ fprintf(stderr, "netlink out of memory error\n");
+ break;
+ case -NLE_AGAIN:
+ fprintf(stderr,
+ "netlink reports blocking read - aborting wait\n");
+ break;
+ default:
+ if (ret)
+ fprintf(stderr, "netlink reports error (%d): %s\n",
+ ret, nl_geterror(-ret));
+ break;
+ }
+
+ return ret;
+}
+
+static struct nl_ctx *nl_ctx_alloc_flags(struct ovpn_ctx *ovpn, int cmd,
+ int flags)
+{
+ struct nl_ctx *ctx;
+ int err, ret;
+
+ ctx = calloc(1, sizeof(*ctx));
+ if (!ctx)
+ return NULL;
+
+ ctx->nl_sock = nl_socket_alloc();
+ if (!ctx->nl_sock) {
+ fprintf(stderr, "cannot allocate netlink socket\n");
+ goto err_free;
+ }
+
+ nl_socket_set_buffer_size(ctx->nl_sock, 8192, 8192);
+
+ ret = genl_connect(ctx->nl_sock);
+ if (ret) {
+ fprintf(stderr, "cannot connect to generic netlink: %s\n",
+ nl_geterror(ret));
+ goto err_sock;
+ }
+
+ /* enable Extended ACK for detailed error reporting */
+ err = 1;
+ setsockopt(nl_socket_get_fd(ctx->nl_sock), SOL_NETLINK, NETLINK_EXT_ACK,
+ &err, sizeof(err));
+
+ ctx->ovpn_dco_id = genl_ctrl_resolve(ctx->nl_sock, OVPN_FAMILY_NAME);
+ if (ctx->ovpn_dco_id < 0) {
+ fprintf(stderr, "cannot find ovpn_dco netlink component: %d\n",
+ ctx->ovpn_dco_id);
+ goto err_free;
+ }
+
+ ctx->nl_msg = nlmsg_alloc();
+ if (!ctx->nl_msg) {
+ fprintf(stderr, "cannot allocate netlink message\n");
+ goto err_sock;
+ }
+
+ ctx->nl_cb = nl_cb_alloc(NL_CB_DEFAULT);
+ if (!ctx->nl_cb) {
+ fprintf(stderr, "failed to allocate netlink callback\n");
+ goto err_msg;
+ }
+
+ nl_socket_set_cb(ctx->nl_sock, ctx->nl_cb);
+
+ genlmsg_put(ctx->nl_msg, 0, 0, ctx->ovpn_dco_id, 0, flags, cmd, 0);
+
+ if (ovpn->ifindex > 0)
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_IFINDEX, ovpn->ifindex);
+
+ return ctx;
+nla_put_failure:
+err_msg:
+ nlmsg_free(ctx->nl_msg);
+err_sock:
+ nl_socket_free(ctx->nl_sock);
+err_free:
+ free(ctx);
+ return NULL;
+}
+
+static struct nl_ctx *nl_ctx_alloc(struct ovpn_ctx *ovpn, int cmd)
+{
+ return nl_ctx_alloc_flags(ovpn, cmd, 0);
+}
+
+static void nl_ctx_free(struct nl_ctx *ctx)
+{
+ if (!ctx)
+ return;
+
+ nl_socket_free(ctx->nl_sock);
+ nlmsg_free(ctx->nl_msg);
+ nl_cb_put(ctx->nl_cb);
+ free(ctx);
+}
+
+static int ovpn_nl_cb_error(struct sockaddr_nl (*nla)__always_unused,
+ struct nlmsgerr *err, void *arg)
+{
+ struct nlmsghdr *nlh = (struct nlmsghdr *)err - 1;
+ struct nlattr *tb_msg[NLMSGERR_ATTR_MAX + 1];
+ int len = nlh->nlmsg_len;
+ struct nlattr *attrs;
+ int *ret = arg;
+ int ack_len = sizeof(*nlh) + sizeof(int) + sizeof(*nlh);
+
+ *ret = err->error;
+
+ if (!(nlh->nlmsg_flags & NLM_F_ACK_TLVS))
+ return NL_STOP;
+
+ if (!(nlh->nlmsg_flags & NLM_F_CAPPED))
+ ack_len += err->msg.nlmsg_len - sizeof(*nlh);
+
+ if (len <= ack_len)
+ return NL_STOP;
+
+ attrs = (void *)((uint8_t *)nlh + ack_len);
+ len -= ack_len;
+
+ nla_parse(tb_msg, NLMSGERR_ATTR_MAX, attrs, len, NULL);
+ if (tb_msg[NLMSGERR_ATTR_MSG]) {
+ len = strnlen((char *)nla_data(tb_msg[NLMSGERR_ATTR_MSG]),
+ nla_len(tb_msg[NLMSGERR_ATTR_MSG]));
+ fprintf(stderr, "kernel error: %*s\n", len,
+ (char *)nla_data(tb_msg[NLMSGERR_ATTR_MSG]));
+ }
+
+ if (tb_msg[NLMSGERR_ATTR_MISS_NEST]) {
+ fprintf(stderr, "missing required nesting type %u\n",
+ nla_get_u32(tb_msg[NLMSGERR_ATTR_MISS_NEST]));
+ }
+
+ if (tb_msg[NLMSGERR_ATTR_MISS_TYPE]) {
+ fprintf(stderr, "missing required attribute type %u\n",
+ nla_get_u32(tb_msg[NLMSGERR_ATTR_MISS_TYPE]));
+ }
+
+ return NL_STOP;
+}
+
+static int ovpn_nl_cb_finish(struct nl_msg (*msg)__always_unused,
+ void *arg)
+{
+ int *status = arg;
+
+ *status = 0;
+ return NL_SKIP;
+}
+
+static int ovpn_nl_cb_ack(struct nl_msg (*msg)__always_unused,
+ void *arg)
+{
+ int *status = arg;
+
+ *status = 0;
+ return NL_STOP;
+}
+
+static int ovpn_nl_msg_send(struct nl_ctx *ctx, ovpn_nl_cb cb)
+{
+ int status = 1;
+
+ nl_cb_err(ctx->nl_cb, NL_CB_CUSTOM, ovpn_nl_cb_error, &status);
+ nl_cb_set(ctx->nl_cb, NL_CB_FINISH, NL_CB_CUSTOM, ovpn_nl_cb_finish,
+ &status);
+ nl_cb_set(ctx->nl_cb, NL_CB_ACK, NL_CB_CUSTOM, ovpn_nl_cb_ack, &status);
+
+ if (cb)
+ nl_cb_set(ctx->nl_cb, NL_CB_VALID, NL_CB_CUSTOM, cb, ctx);
+
+ nl_send_auto_complete(ctx->nl_sock, ctx->nl_msg);
+
+ while (status == 1)
+ ovpn_nl_recvmsgs(ctx);
+
+ if (status < 0)
+ fprintf(stderr, "failed to send netlink message: %s (%d)\n",
+ strerror(-status), status);
+
+ return status;
+}
+
+static int ovpn_parse_key(const char *file, struct ovpn_ctx *ctx)
+{
+ int idx_enc, idx_dec, ret = -1;
+ unsigned char *ckey = NULL;
+ __u8 *bkey = NULL;
+ size_t olen = 0;
+ long ckey_len;
+ FILE *fp;
+
+ fp = fopen(file, "r");
+ if (!fp) {
+ fprintf(stderr, "cannot open: %s\n", file);
+ return -1;
+ }
+
+ /* get file size */
+ fseek(fp, 0L, SEEK_END);
+ ckey_len = ftell(fp);
+ rewind(fp);
+
+ /* if the file is longer, let's just read a portion */
+ if (ckey_len > 256)
+ ckey_len = 256;
+
+ ckey = malloc(ckey_len);
+ if (!ckey)
+ goto err;
+
+ ret = fread(ckey, 1, ckey_len, fp);
+ if (ret != ckey_len) {
+ fprintf(stderr,
+ "couldn't read enough data from key file: %dbytes read\n",
+ ret);
+ goto err;
+ }
+
+ olen = 0;
+ ret = mbedtls_base64_decode(NULL, 0, &olen, ckey, ckey_len);
+ if (ret != MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL) {
+ char buf[256];
+
+ mbedtls_strerror(ret, buf, sizeof(buf));
+ fprintf(stderr, "unexpected base64 error1: %s (%d)\n", buf,
+ ret);
+
+ goto err;
+ }
+
+ bkey = malloc(olen);
+ if (!bkey) {
+ fprintf(stderr, "cannot allocate binary key buffer\n");
+ goto err;
+ }
+
+ ret = mbedtls_base64_decode(bkey, olen, &olen, ckey, ckey_len);
+ if (ret) {
+ char buf[256];
+
+ mbedtls_strerror(ret, buf, sizeof(buf));
+ fprintf(stderr, "unexpected base64 error2: %s (%d)\n", buf,
+ ret);
+
+ goto err;
+ }
+
+ if (olen < 2 * KEY_LEN + NONCE_LEN) {
+ fprintf(stderr,
+ "not enough data in key file, found %zdB but needs %dB\n",
+ olen, 2 * KEY_LEN + NONCE_LEN);
+ goto err;
+ }
+
+ switch (ctx->key_dir) {
+ case KEY_DIR_IN:
+ idx_enc = 0;
+ idx_dec = 1;
+ break;
+ case KEY_DIR_OUT:
+ idx_enc = 1;
+ idx_dec = 0;
+ break;
+ default:
+ goto err;
+ }
+
+ memcpy(ctx->key_enc, bkey + KEY_LEN * idx_enc, KEY_LEN);
+ memcpy(ctx->key_dec, bkey + KEY_LEN * idx_dec, KEY_LEN);
+ memcpy(ctx->nonce, bkey + 2 * KEY_LEN, NONCE_LEN);
+
+ ret = 0;
+
+err:
+ fclose(fp);
+ free(bkey);
+ free(ckey);
+
+ return ret;
+}
+
+static int ovpn_parse_cipher(const char *cipher, struct ovpn_ctx *ctx)
+{
+ if (strcmp(cipher, "aes") == 0)
+ ctx->cipher = OVPN_CIPHER_ALG_AES_GCM;
+ else if (strcmp(cipher, "chachapoly") == 0)
+ ctx->cipher = OVPN_CIPHER_ALG_CHACHA20_POLY1305;
+ else if (strcmp(cipher, "none") == 0)
+ ctx->cipher = OVPN_CIPHER_ALG_NONE;
+ else
+ return -ENOTSUP;
+
+ return 0;
+}
+
+static int ovpn_parse_key_direction(const char *dir, struct ovpn_ctx *ctx)
+{
+ int in_dir;
+
+ in_dir = strtoll(dir, NULL, 10);
+ switch (in_dir) {
+ case KEY_DIR_IN:
+ case KEY_DIR_OUT:
+ ctx->key_dir = in_dir;
+ break;
+ default:
+ fprintf(stderr,
+ "invalid key direction provided. Can be 0 or 1 only\n");
+ return -1;
+ }
+
+ return 0;
+}
+
+static int ovpn_socket(struct ovpn_ctx *ctx, sa_family_t family, int proto)
+{
+ struct sockaddr_storage local_sock = { 0 };
+ struct sockaddr_in6 *in6;
+ struct sockaddr_in *in;
+ int ret, s, sock_type;
+ size_t sock_len;
+
+ if (proto == IPPROTO_UDP)
+ sock_type = SOCK_DGRAM;
+ else if (proto == IPPROTO_TCP)
+ sock_type = SOCK_STREAM;
+ else
+ return -EINVAL;
+
+ s = socket(family, sock_type, 0);
+ if (s < 0) {
+ perror("cannot create socket");
+ return -1;
+ }
+
+ switch (family) {
+ case AF_INET:
+ in = (struct sockaddr_in *)&local_sock;
+ in->sin_family = family;
+ in->sin_port = htons(ctx->lport);
+ in->sin_addr.s_addr = htonl(INADDR_ANY);
+ sock_len = sizeof(*in);
+ break;
+ case AF_INET6:
+ in6 = (struct sockaddr_in6 *)&local_sock;
+ in6->sin6_family = family;
+ in6->sin6_port = htons(ctx->lport);
+ in6->sin6_addr = in6addr_any;
+ sock_len = sizeof(*in6);
+ break;
+ default:
+ return -1;
+ }
+
+ int opt = 1;
+
+ ret = setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
+
+ if (ret < 0) {
+ perror("setsockopt for SO_REUSEADDR");
+ return ret;
+ }
+
+ ret = setsockopt(s, SOL_SOCKET, SO_REUSEPORT, &opt, sizeof(opt));
+ if (ret < 0) {
+ perror("setsockopt for SO_REUSEPORT");
+ return ret;
+ }
+
+ if (family == AF_INET6) {
+ opt = 0;
+ if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &opt,
+ sizeof(opt))) {
+ perror("failed to set IPV6_V6ONLY");
+ return -1;
+ }
+ }
+
+ ret = bind(s, (struct sockaddr *)&local_sock, sock_len);
+ if (ret < 0) {
+ perror("cannot bind socket");
+ goto err_socket;
+ }
+
+ ctx->socket = s;
+ ctx->sa_family = family;
+ return 0;
+
+err_socket:
+ close(s);
+ return -1;
+}
+
+static int ovpn_udp_socket(struct ovpn_ctx *ctx, sa_family_t family)
+{
+ return ovpn_socket(ctx, family, IPPROTO_UDP);
+}
+
+static int ovpn_listen(struct ovpn_ctx *ctx, sa_family_t family)
+{
+ int ret;
+
+ ret = ovpn_socket(ctx, family, IPPROTO_TCP);
+ if (ret < 0)
+ return ret;
+
+ ret = listen(ctx->socket, 10);
+ if (ret < 0) {
+ perror("listen");
+ close(ctx->socket);
+ return -1;
+ }
+
+ return 0;
+}
+
+static int ovpn_accept(struct ovpn_ctx *ctx)
+{
+ socklen_t socklen;
+ int ret;
+
+ socklen = sizeof(ctx->remote);
+ ret = accept(ctx->socket, (struct sockaddr *)&ctx->remote, &socklen);
+ if (ret < 0) {
+ perror("accept");
+ goto err;
+ }
+
+ fprintf(stderr, "Connection received!\n");
+
+ switch (socklen) {
+ case sizeof(struct sockaddr_in):
+ case sizeof(struct sockaddr_in6):
+ break;
+ default:
+ fprintf(stderr, "error: expecting IPv4 or IPv6 connection\n");
+ close(ret);
+ ret = -EINVAL;
+ goto err;
+ }
+
+ return ret;
+err:
+ close(ctx->socket);
+ return ret;
+}
+
+static int ovpn_connect(struct ovpn_ctx *ovpn)
+{
+ socklen_t socklen;
+ int s, ret;
+
+ s = socket(ovpn->remote.in4.sin_family, SOCK_STREAM, 0);
+ if (s < 0) {
+ perror("cannot create socket");
+ return -1;
+ }
+
+ switch (ovpn->remote.in4.sin_family) {
+ case AF_INET:
+ socklen = sizeof(struct sockaddr_in);
+ break;
+ case AF_INET6:
+ socklen = sizeof(struct sockaddr_in6);
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ ret = connect(s, (struct sockaddr *)&ovpn->remote, socklen);
+ if (ret < 0) {
+ perror("connect");
+ goto err;
+ }
+
+ fprintf(stderr, "connected\n");
+
+ ovpn->socket = s;
+
+ return 0;
+err:
+ close(s);
+ return ret;
+}
+
+static int ovpn_new_peer(struct ovpn_ctx *ovpn, bool is_tcp)
+{
+ struct nlattr *attr;
+ struct nl_ctx *ctx;
+ int ret = -1;
+
+ ctx = nl_ctx_alloc(ovpn, OVPN_CMD_PEER_NEW);
+ if (!ctx)
+ return -ENOMEM;
+
+ attr = nla_nest_start(ctx->nl_msg, OVPN_A_PEER);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_SOCKET, ovpn->socket);
+
+ if (!is_tcp) {
+ switch (ovpn->remote.in4.sin_family) {
+ case AF_INET:
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_REMOTE_IPV4,
+ ovpn->remote.in4.sin_addr.s_addr);
+ NLA_PUT_U16(ctx->nl_msg, OVPN_A_PEER_REMOTE_PORT,
+ ovpn->remote.in4.sin_port);
+ break;
+ case AF_INET6:
+ NLA_PUT(ctx->nl_msg, OVPN_A_PEER_REMOTE_IPV6,
+ sizeof(ovpn->remote.in6.sin6_addr),
+ &ovpn->remote.in6.sin6_addr);
+ NLA_PUT_U32(ctx->nl_msg,
+ OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID,
+ ovpn->remote.in6.sin6_scope_id);
+ NLA_PUT_U16(ctx->nl_msg, OVPN_A_PEER_REMOTE_PORT,
+ ovpn->remote.in6.sin6_port);
+ break;
+ default:
+ fprintf(stderr,
+ "Invalid family for remote socket address\n");
+ goto nla_put_failure;
+ }
+ }
+
+ if (ovpn->peer_ip_set) {
+ switch (ovpn->peer_ip.in4.sin_family) {
+ case AF_INET:
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_VPN_IPV4,
+ ovpn->peer_ip.in4.sin_addr.s_addr);
+ break;
+ case AF_INET6:
+ NLA_PUT(ctx->nl_msg, OVPN_A_PEER_VPN_IPV6,
+ sizeof(struct in6_addr),
+ &ovpn->peer_ip.in6.sin6_addr);
+ break;
+ default:
+ fprintf(stderr, "Invalid family for peer address\n");
+ goto nla_put_failure;
+ }
+ }
+
+ nla_nest_end(ctx->nl_msg, attr);
+
+ ret = ovpn_nl_msg_send(ctx, NULL);
+nla_put_failure:
+ nl_ctx_free(ctx);
+ return ret;
+}
+
+static int ovpn_set_peer(struct ovpn_ctx *ovpn)
+{
+ struct nlattr *attr;
+ struct nl_ctx *ctx;
+ int ret = -1;
+
+ ctx = nl_ctx_alloc(ovpn, OVPN_CMD_PEER_SET);
+ if (!ctx)
+ return -ENOMEM;
+
+ attr = nla_nest_start(ctx->nl_msg, OVPN_A_PEER);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_KEEPALIVE_INTERVAL,
+ ovpn->keepalive_interval);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_KEEPALIVE_TIMEOUT,
+ ovpn->keepalive_timeout);
+ nla_nest_end(ctx->nl_msg, attr);
+
+ ret = ovpn_nl_msg_send(ctx, NULL);
+nla_put_failure:
+ nl_ctx_free(ctx);
+ return ret;
+}
+
+static int ovpn_del_peer(struct ovpn_ctx *ovpn)
+{
+ struct nlattr *attr;
+ struct nl_ctx *ctx;
+ int ret = -1;
+
+ ctx = nl_ctx_alloc(ovpn, OVPN_CMD_PEER_DEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ attr = nla_nest_start(ctx->nl_msg, OVPN_A_PEER);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id);
+ nla_nest_end(ctx->nl_msg, attr);
+
+ ret = ovpn_nl_msg_send(ctx, NULL);
+nla_put_failure:
+ nl_ctx_free(ctx);
+ return ret;
+}
+
+static int ovpn_handle_peer(struct nl_msg *msg, void (*arg)__always_unused)
+{
+ struct nlattr *pattrs[OVPN_A_PEER_MAX + 1];
+ struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
+ struct nlattr *attrs[OVPN_A_MAX + 1];
+ __u16 rport = 0, lport = 0;
+
+ nla_parse(attrs, OVPN_A_MAX, genlmsg_attrdata(gnlh, 0),
+ genlmsg_attrlen(gnlh, 0), NULL);
+
+ if (!attrs[OVPN_A_PEER]) {
+ fprintf(stderr, "no packet content in netlink message\n");
+ return NL_SKIP;
+ }
+
+ nla_parse(pattrs, OVPN_A_PEER_MAX, nla_data(attrs[OVPN_A_PEER]),
+ nla_len(attrs[OVPN_A_PEER]), NULL);
+
+ if (pattrs[OVPN_A_PEER_ID])
+ fprintf(stderr, "* Peer %u\n",
+ nla_get_u32(pattrs[OVPN_A_PEER_ID]));
+
+ if (pattrs[OVPN_A_PEER_SOCKET_NETNSID])
+ fprintf(stderr, "\tsocket NetNS ID: %d\n",
+ nla_get_s32(pattrs[OVPN_A_PEER_SOCKET_NETNSID]));
+
+ if (pattrs[OVPN_A_PEER_VPN_IPV4]) {
+ char buf[INET_ADDRSTRLEN];
+
+ inet_ntop(AF_INET, nla_data(pattrs[OVPN_A_PEER_VPN_IPV4]),
+ buf, sizeof(buf));
+ fprintf(stderr, "\tVPN IPv4: %s\n", buf);
+ }
+
+ if (pattrs[OVPN_A_PEER_VPN_IPV6]) {
+ char buf[INET6_ADDRSTRLEN];
+
+ inet_ntop(AF_INET6, nla_data(pattrs[OVPN_A_PEER_VPN_IPV6]),
+ buf, sizeof(buf));
+ fprintf(stderr, "\tVPN IPv6: %s\n", buf);
+ }
+
+ if (pattrs[OVPN_A_PEER_LOCAL_PORT])
+ lport = ntohs(nla_get_u16(pattrs[OVPN_A_PEER_LOCAL_PORT]));
+
+ if (pattrs[OVPN_A_PEER_REMOTE_PORT])
+ rport = ntohs(nla_get_u16(pattrs[OVPN_A_PEER_REMOTE_PORT]));
+
+ if (pattrs[OVPN_A_PEER_REMOTE_IPV6]) {
+ void *ip = pattrs[OVPN_A_PEER_REMOTE_IPV6];
+ char buf[INET6_ADDRSTRLEN];
+ int scope_id = -1;
+
+ if (pattrs[OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID]) {
+ void *p = pattrs[OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID];
+
+ scope_id = nla_get_u32(p);
+ }
+
+ inet_ntop(AF_INET6, nla_data(ip), buf, sizeof(buf));
+ fprintf(stderr, "\tRemote: %s:%hu (scope-id: %u)\n", buf, rport,
+ scope_id);
+
+ if (pattrs[OVPN_A_PEER_LOCAL_IPV6]) {
+ void *ip = pattrs[OVPN_A_PEER_LOCAL_IPV6];
+
+ inet_ntop(AF_INET6, nla_data(ip), buf, sizeof(buf));
+ fprintf(stderr, "\tLocal: %s:%hu\n", buf, lport);
+ }
+ }
+
+ if (pattrs[OVPN_A_PEER_REMOTE_IPV4]) {
+ void *ip = pattrs[OVPN_A_PEER_REMOTE_IPV4];
+ char buf[INET_ADDRSTRLEN];
+
+ inet_ntop(AF_INET, nla_data(ip), buf, sizeof(buf));
+ fprintf(stderr, "\tRemote: %s:%hu\n", buf, rport);
+
+ if (pattrs[OVPN_A_PEER_LOCAL_IPV4]) {
+ void *p = pattrs[OVPN_A_PEER_LOCAL_IPV4];
+
+ inet_ntop(AF_INET, nla_data(p), buf, sizeof(buf));
+ fprintf(stderr, "\tLocal: %s:%hu\n", buf, lport);
+ }
+ }
+
+ if (pattrs[OVPN_A_PEER_KEEPALIVE_INTERVAL]) {
+ void *p = pattrs[OVPN_A_PEER_KEEPALIVE_INTERVAL];
+
+ fprintf(stderr, "\tKeepalive interval: %u sec\n",
+ nla_get_u32(p));
+ }
+
+ if (pattrs[OVPN_A_PEER_KEEPALIVE_TIMEOUT])
+ fprintf(stderr, "\tKeepalive timeout: %u sec\n",
+ nla_get_u32(pattrs[OVPN_A_PEER_KEEPALIVE_TIMEOUT]));
+
+ if (pattrs[OVPN_A_PEER_VPN_RX_BYTES])
+ fprintf(stderr, "\tVPN RX bytes: %" PRIu64 "\n",
+ ovpn_nla_get_uint(pattrs[OVPN_A_PEER_VPN_RX_BYTES]));
+
+ if (pattrs[OVPN_A_PEER_VPN_TX_BYTES])
+ fprintf(stderr, "\tVPN TX bytes: %" PRIu64 "\n",
+ ovpn_nla_get_uint(pattrs[OVPN_A_PEER_VPN_TX_BYTES]));
+
+ if (pattrs[OVPN_A_PEER_VPN_RX_PACKETS])
+ fprintf(stderr, "\tVPN RX packets: %" PRIu64 "\n",
+ ovpn_nla_get_uint(pattrs[OVPN_A_PEER_VPN_RX_PACKETS]));
+
+ if (pattrs[OVPN_A_PEER_VPN_TX_PACKETS])
+ fprintf(stderr, "\tVPN TX packets: %" PRIu64 "\n",
+ ovpn_nla_get_uint(pattrs[OVPN_A_PEER_VPN_TX_PACKETS]));
+
+ if (pattrs[OVPN_A_PEER_LINK_RX_BYTES])
+ fprintf(stderr, "\tLINK RX bytes: %" PRIu64 "\n",
+ ovpn_nla_get_uint(pattrs[OVPN_A_PEER_LINK_RX_BYTES]));
+
+ if (pattrs[OVPN_A_PEER_LINK_TX_BYTES])
+ fprintf(stderr, "\tLINK TX bytes: %" PRIu64 "\n",
+ ovpn_nla_get_uint(pattrs[OVPN_A_PEER_LINK_TX_BYTES]));
+
+ if (pattrs[OVPN_A_PEER_LINK_RX_PACKETS])
+ fprintf(stderr, "\tLINK RX packets: %" PRIu64 "\n",
+ ovpn_nla_get_uint(pattrs[OVPN_A_PEER_LINK_RX_PACKETS]));
+
+ if (pattrs[OVPN_A_PEER_LINK_TX_PACKETS])
+ fprintf(stderr, "\tLINK TX packets: %" PRIu64 "\n",
+ ovpn_nla_get_uint(pattrs[OVPN_A_PEER_LINK_TX_PACKETS]));
+
+ return NL_SKIP;
+}
+
+static int ovpn_get_peer(struct ovpn_ctx *ovpn)
+{
+ int flags = 0, ret = -1;
+ struct nlattr *attr;
+ struct nl_ctx *ctx;
+
+ if (ovpn->peer_id == PEER_ID_UNDEF)
+ flags = NLM_F_DUMP;
+
+ ctx = nl_ctx_alloc_flags(ovpn, OVPN_CMD_PEER_GET, flags);
+ if (!ctx)
+ return -ENOMEM;
+
+ if (ovpn->peer_id != PEER_ID_UNDEF) {
+ attr = nla_nest_start(ctx->nl_msg, OVPN_A_PEER);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id);
+ nla_nest_end(ctx->nl_msg, attr);
+ }
+
+ ret = ovpn_nl_msg_send(ctx, ovpn_handle_peer);
+nla_put_failure:
+ nl_ctx_free(ctx);
+ return ret;
+}
+
+static int ovpn_new_key(struct ovpn_ctx *ovpn)
+{
+ struct nlattr *keyconf, *key_dir;
+ struct nl_ctx *ctx;
+ int ret = -1;
+
+ ctx = nl_ctx_alloc(ovpn, OVPN_CMD_KEY_NEW);
+ if (!ctx)
+ return -ENOMEM;
+
+ keyconf = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_PEER_ID, ovpn->peer_id);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_SLOT, ovpn->key_slot);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_KEY_ID, ovpn->key_id);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_CIPHER_ALG, ovpn->cipher);
+
+ key_dir = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF_ENCRYPT_DIR);
+ NLA_PUT(ctx->nl_msg, OVPN_A_KEYDIR_CIPHER_KEY, KEY_LEN, ovpn->key_enc);
+ NLA_PUT(ctx->nl_msg, OVPN_A_KEYDIR_NONCE_TAIL, NONCE_LEN, ovpn->nonce);
+ nla_nest_end(ctx->nl_msg, key_dir);
+
+ key_dir = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF_DECRYPT_DIR);
+ NLA_PUT(ctx->nl_msg, OVPN_A_KEYDIR_CIPHER_KEY, KEY_LEN, ovpn->key_dec);
+ NLA_PUT(ctx->nl_msg, OVPN_A_KEYDIR_NONCE_TAIL, NONCE_LEN, ovpn->nonce);
+ nla_nest_end(ctx->nl_msg, key_dir);
+
+ nla_nest_end(ctx->nl_msg, keyconf);
+
+ ret = ovpn_nl_msg_send(ctx, NULL);
+nla_put_failure:
+ nl_ctx_free(ctx);
+ return ret;
+}
+
+static int ovpn_del_key(struct ovpn_ctx *ovpn)
+{
+ struct nlattr *keyconf;
+ struct nl_ctx *ctx;
+ int ret = -1;
+
+ ctx = nl_ctx_alloc(ovpn, OVPN_CMD_KEY_DEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ keyconf = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_PEER_ID, ovpn->peer_id);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_SLOT, ovpn->key_slot);
+ nla_nest_end(ctx->nl_msg, keyconf);
+
+ ret = ovpn_nl_msg_send(ctx, NULL);
+nla_put_failure:
+ nl_ctx_free(ctx);
+ return ret;
+}
+
+static int ovpn_handle_key(struct nl_msg *msg, void (*arg)__always_unused)
+{
+ struct nlattr *kattrs[OVPN_A_KEYCONF_MAX + 1];
+ struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
+ struct nlattr *attrs[OVPN_A_MAX + 1];
+
+ nla_parse(attrs, OVPN_A_MAX, genlmsg_attrdata(gnlh, 0),
+ genlmsg_attrlen(gnlh, 0), NULL);
+
+ if (!attrs[OVPN_A_KEYCONF]) {
+ fprintf(stderr, "no packet content in netlink message\n");
+ return NL_SKIP;
+ }
+
+ nla_parse(kattrs, OVPN_A_KEYCONF_MAX, nla_data(attrs[OVPN_A_KEYCONF]),
+ nla_len(attrs[OVPN_A_KEYCONF]), NULL);
+
+ if (kattrs[OVPN_A_KEYCONF_PEER_ID])
+ fprintf(stderr, "* Peer %u\n",
+ nla_get_u32(kattrs[OVPN_A_KEYCONF_PEER_ID]));
+ if (kattrs[OVPN_A_KEYCONF_SLOT]) {
+ fprintf(stderr, "\t- Slot: ");
+ switch (nla_get_u32(kattrs[OVPN_A_KEYCONF_SLOT])) {
+ case OVPN_KEY_SLOT_PRIMARY:
+ fprintf(stderr, "primary\n");
+ break;
+ case OVPN_KEY_SLOT_SECONDARY:
+ fprintf(stderr, "secondary\n");
+ break;
+ default:
+ fprintf(stderr, "invalid (%u)\n",
+ nla_get_u32(kattrs[OVPN_A_KEYCONF_SLOT]));
+ break;
+ }
+ }
+ if (kattrs[OVPN_A_KEYCONF_KEY_ID])
+ fprintf(stderr, "\t- Key ID: %u\n",
+ nla_get_u32(kattrs[OVPN_A_KEYCONF_KEY_ID]));
+ if (kattrs[OVPN_A_KEYCONF_CIPHER_ALG]) {
+ fprintf(stderr, "\t- Cipher: ");
+ switch (nla_get_u32(kattrs[OVPN_A_KEYCONF_CIPHER_ALG])) {
+ case OVPN_CIPHER_ALG_NONE:
+ fprintf(stderr, "none\n");
+ break;
+ case OVPN_CIPHER_ALG_AES_GCM:
+ fprintf(stderr, "aes-gcm\n");
+ break;
+ case OVPN_CIPHER_ALG_CHACHA20_POLY1305:
+ fprintf(stderr, "chacha20poly1305\n");
+ break;
+ default:
+ fprintf(stderr, "invalid (%u)\n",
+ nla_get_u32(kattrs[OVPN_A_KEYCONF_CIPHER_ALG]));
+ break;
+ }
+ }
+
+ return NL_SKIP;
+}
+
+static int ovpn_get_key(struct ovpn_ctx *ovpn)
+{
+ struct nlattr *keyconf;
+ struct nl_ctx *ctx;
+ int ret = -1;
+
+ ctx = nl_ctx_alloc(ovpn, OVPN_CMD_KEY_GET);
+ if (!ctx)
+ return -ENOMEM;
+
+ keyconf = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_PEER_ID, ovpn->peer_id);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_SLOT, ovpn->key_slot);
+ nla_nest_end(ctx->nl_msg, keyconf);
+
+ ret = ovpn_nl_msg_send(ctx, ovpn_handle_key);
+nla_put_failure:
+ nl_ctx_free(ctx);
+ return ret;
+}
+
+static int ovpn_swap_keys(struct ovpn_ctx *ovpn)
+{
+ struct nl_ctx *ctx;
+ struct nlattr *kc;
+ int ret = -1;
+
+ ctx = nl_ctx_alloc(ovpn, OVPN_CMD_KEY_SWAP);
+ if (!ctx)
+ return -ENOMEM;
+
+ kc = nla_nest_start(ctx->nl_msg, OVPN_A_KEYCONF);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_PEER_ID, ovpn->peer_id);
+ nla_nest_end(ctx->nl_msg, kc);
+
+ ret = ovpn_nl_msg_send(ctx, NULL);
+nla_put_failure:
+ nl_ctx_free(ctx);
+ return ret;
+}
+
+/* Helper function used to easily add attributes to a rtnl message */
+static int ovpn_addattr(struct nlmsghdr *n, int maxlen, int type,
+ const void *data, int alen)
+{
+ int len = RTA_LENGTH(alen);
+ struct rtattr *rta;
+
+ if ((int)(NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len)) > maxlen) {
+ fprintf(stderr, "%s: rtnl: message exceeded bound of %d\n",
+ __func__, maxlen);
+ return -EMSGSIZE;
+ }
+
+ rta = nlmsg_tail(n);
+ rta->rta_type = type;
+ rta->rta_len = len;
+
+ if (!data)
+ memset(RTA_DATA(rta), 0, alen);
+ else
+ memcpy(RTA_DATA(rta), data, alen);
+
+ n->nlmsg_len = NLMSG_ALIGN(n->nlmsg_len) + RTA_ALIGN(len);
+
+ return 0;
+}
+
+static struct rtattr *ovpn_nest_start(struct nlmsghdr *msg, size_t max_size,
+ int attr)
+{
+ struct rtattr *nest = nlmsg_tail(msg);
+
+ if (ovpn_addattr(msg, max_size, attr, NULL, 0) < 0)
+ return NULL;
+
+ return nest;
+}
+
+static void ovpn_nest_end(struct nlmsghdr *msg, struct rtattr *nest)
+{
+ nest->rta_len = (uint8_t *)nlmsg_tail(msg) - (uint8_t *)nest;
+}
+
+#define RT_SNDBUF_SIZE (1024 * 2)
+#define RT_RCVBUF_SIZE (1024 * 4)
+
+/* Open RTNL socket */
+static int ovpn_rt_socket(void)
+{
+ int sndbuf = RT_SNDBUF_SIZE, rcvbuf = RT_RCVBUF_SIZE, fd;
+
+ fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+ if (fd < 0) {
+ fprintf(stderr, "%s: cannot open netlink socket\n", __func__);
+ return fd;
+ }
+
+ if (setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &sndbuf,
+ sizeof(sndbuf)) < 0) {
+ fprintf(stderr, "%s: SO_SNDBUF\n", __func__);
+ close(fd);
+ return -1;
+ }
+
+ if (setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &rcvbuf,
+ sizeof(rcvbuf)) < 0) {
+ fprintf(stderr, "%s: SO_RCVBUF\n", __func__);
+ close(fd);
+ return -1;
+ }
+
+ return fd;
+}
+
+/* Bind socket to Netlink subsystem */
+static int ovpn_rt_bind(int fd, uint32_t groups)
+{
+ struct sockaddr_nl local = { 0 };
+ socklen_t addr_len;
+
+ local.nl_family = AF_NETLINK;
+ local.nl_groups = groups;
+
+ if (bind(fd, (struct sockaddr *)&local, sizeof(local)) < 0) {
+ fprintf(stderr, "%s: cannot bind netlink socket: %d\n",
+ __func__, errno);
+ return -errno;
+ }
+
+ addr_len = sizeof(local);
+ if (getsockname(fd, (struct sockaddr *)&local, &addr_len) < 0) {
+ fprintf(stderr, "%s: cannot getsockname: %d\n", __func__,
+ errno);
+ return -errno;
+ }
+
+ if (addr_len != sizeof(local)) {
+ fprintf(stderr, "%s: wrong address length %d\n", __func__,
+ addr_len);
+ return -EINVAL;
+ }
+
+ if (local.nl_family != AF_NETLINK) {
+ fprintf(stderr, "%s: wrong address family %d\n", __func__,
+ local.nl_family);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+typedef int (*ovpn_parse_reply_cb)(struct nlmsghdr *msg, void *arg);
+
+/* Send Netlink message and run callback on reply (if specified) */
+static int ovpn_rt_send(struct nlmsghdr *payload, pid_t peer,
+ unsigned int groups, ovpn_parse_reply_cb cb,
+ void *arg_cb)
+{
+ int len, rem_len, fd, ret, rcv_len;
+ struct sockaddr_nl nladdr = { 0 };
+ struct nlmsgerr *err;
+ struct nlmsghdr *h;
+ char buf[1024 * 16];
+ struct iovec iov = {
+ .iov_base = payload,
+ .iov_len = payload->nlmsg_len,
+ };
+ struct msghdr nlmsg = {
+ .msg_name = &nladdr,
+ .msg_namelen = sizeof(nladdr),
+ .msg_iov = &iov,
+ .msg_iovlen = 1,
+ };
+
+ nladdr.nl_family = AF_NETLINK;
+ nladdr.nl_pid = peer;
+ nladdr.nl_groups = groups;
+
+ payload->nlmsg_seq = time(NULL);
+
+ /* no need to send reply */
+ if (!cb)
+ payload->nlmsg_flags |= NLM_F_ACK;
+
+ fd = ovpn_rt_socket();
+ if (fd < 0) {
+ fprintf(stderr, "%s: can't open rtnl socket\n", __func__);
+ return -errno;
+ }
+
+ ret = ovpn_rt_bind(fd, 0);
+ if (ret < 0) {
+ fprintf(stderr, "%s: can't bind rtnl socket\n", __func__);
+ ret = -errno;
+ goto out;
+ }
+
+ ret = sendmsg(fd, &nlmsg, 0);
+ if (ret < 0) {
+ fprintf(stderr, "%s: rtnl: error on sendmsg()\n", __func__);
+ ret = -errno;
+ goto out;
+ }
+
+ /* prepare buffer to store RTNL replies */
+ memset(buf, 0, sizeof(buf));
+ iov.iov_base = buf;
+
+ while (1) {
+ /*
+ * iov_len is modified by recvmsg(), therefore has to be initialized before
+ * using it again
+ */
+ iov.iov_len = sizeof(buf);
+ rcv_len = recvmsg(fd, &nlmsg, 0);
+ if (rcv_len < 0) {
+ if (errno == EINTR || errno == EAGAIN) {
+ fprintf(stderr, "%s: interrupted call\n",
+ __func__);
+ continue;
+ }
+ fprintf(stderr, "%s: rtnl: error on recvmsg()\n",
+ __func__);
+ ret = -errno;
+ goto out;
+ }
+
+ if (rcv_len == 0) {
+ fprintf(stderr,
+ "%s: rtnl: socket reached unexpected EOF\n",
+ __func__);
+ ret = -EIO;
+ goto out;
+ }
+
+ if (nlmsg.msg_namelen != sizeof(nladdr)) {
+ fprintf(stderr,
+ "%s: sender address length: %u (expected %zu)\n",
+ __func__, nlmsg.msg_namelen, sizeof(nladdr));
+ ret = -EIO;
+ goto out;
+ }
+
+ h = (struct nlmsghdr *)buf;
+ while (rcv_len >= (int)sizeof(*h)) {
+ len = h->nlmsg_len;
+ rem_len = len - sizeof(*h);
+
+ if (rem_len < 0 || len > rcv_len) {
+ if (nlmsg.msg_flags & MSG_TRUNC) {
+ fprintf(stderr, "%s: truncated message\n",
+ __func__);
+ ret = -EIO;
+ goto out;
+ }
+ fprintf(stderr, "%s: malformed message: len=%d\n",
+ __func__, len);
+ ret = -EIO;
+ goto out;
+ }
+
+ if (h->nlmsg_type == NLMSG_DONE) {
+ ret = 0;
+ goto out;
+ }
+
+ if (h->nlmsg_type == NLMSG_ERROR) {
+ err = (struct nlmsgerr *)NLMSG_DATA(h);
+ if (rem_len < (int)sizeof(struct nlmsgerr)) {
+ fprintf(stderr, "%s: ERROR truncated\n",
+ __func__);
+ ret = -EIO;
+ goto out;
+ }
+
+ if (err->error) {
+ fprintf(stderr, "%s: (%d) %s\n",
+ __func__, err->error,
+ strerror(-err->error));
+ ret = err->error;
+ goto out;
+ }
+
+ ret = 0;
+ if (cb) {
+ int r = cb(h, arg_cb);
+
+ if (r <= 0)
+ ret = r;
+ }
+ goto out;
+ }
+
+ if (cb) {
+ int r = cb(h, arg_cb);
+
+ if (r <= 0) {
+ ret = r;
+ goto out;
+ }
+ } else {
+ fprintf(stderr, "%s: RTNL: unexpected reply\n",
+ __func__);
+ }
+
+ rcv_len -= NLMSG_ALIGN(len);
+ h = (struct nlmsghdr *)((uint8_t *)h +
+ NLMSG_ALIGN(len));
+ }
+
+ if (nlmsg.msg_flags & MSG_TRUNC) {
+ fprintf(stderr, "%s: message truncated\n", __func__);
+ continue;
+ }
+
+ if (rcv_len) {
+ fprintf(stderr, "%s: rtnl: %d not parsed bytes\n",
+ __func__, rcv_len);
+ ret = -1;
+ goto out;
+ }
+ }
+out:
+ close(fd);
+
+ return ret;
+}
+
+struct ovpn_link_req {
+ struct nlmsghdr n;
+ struct ifinfomsg i;
+ char buf[256];
+};
+
+static int ovpn_new_iface(struct ovpn_ctx *ovpn)
+{
+ struct rtattr *linkinfo, *data;
+ struct ovpn_link_req req = { 0 };
+ int ret = -1;
+
+ fprintf(stdout, "Creating interface %s with mode %u\n", ovpn->ifname,
+ ovpn->mode);
+
+ req.n.nlmsg_len = NLMSG_LENGTH(sizeof(req.i));
+ req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_EXCL;
+ req.n.nlmsg_type = RTM_NEWLINK;
+
+ if (ovpn_addattr(&req.n, sizeof(req), IFLA_IFNAME, ovpn->ifname,
+ strlen(ovpn->ifname) + 1) < 0)
+ goto err;
+
+ linkinfo = ovpn_nest_start(&req.n, sizeof(req), IFLA_LINKINFO);
+ if (!linkinfo)
+ goto err;
+
+ if (ovpn_addattr(&req.n, sizeof(req), IFLA_INFO_KIND, OVPN_FAMILY_NAME,
+ strlen(OVPN_FAMILY_NAME) + 1) < 0)
+ goto err;
+
+ if (ovpn->mode_set) {
+ data = ovpn_nest_start(&req.n, sizeof(req), IFLA_INFO_DATA);
+ if (!data)
+ goto err;
+
+ if (ovpn_addattr(&req.n, sizeof(req), IFLA_OVPN_MODE,
+ &ovpn->mode, sizeof(uint8_t)) < 0)
+ goto err;
+
+ ovpn_nest_end(&req.n, data);
+ }
+
+ ovpn_nest_end(&req.n, linkinfo);
+
+ req.i.ifi_family = AF_PACKET;
+
+ ret = ovpn_rt_send(&req.n, 0, 0, NULL, NULL);
+err:
+ return ret;
+}
+
+static int ovpn_del_iface(struct ovpn_ctx *ovpn)
+{
+ struct ovpn_link_req req = { 0 };
+
+ fprintf(stdout, "Deleting interface %s ifindex %u\n", ovpn->ifname,
+ ovpn->ifindex);
+
+ req.n.nlmsg_len = NLMSG_LENGTH(sizeof(req.i));
+ req.n.nlmsg_flags = NLM_F_REQUEST;
+ req.n.nlmsg_type = RTM_DELLINK;
+
+ req.i.ifi_family = AF_PACKET;
+ req.i.ifi_index = ovpn->ifindex;
+
+ return ovpn_rt_send(&req.n, 0, 0, NULL, NULL);
+}
+
+static int nl_seq_check(struct nl_msg (*msg)__always_unused,
+ void (*arg)__always_unused)
+{
+ return NL_OK;
+}
+
+struct mcast_handler_args {
+ const char *group;
+ int id;
+};
+
+static int mcast_family_handler(struct nl_msg *msg, void *arg)
+{
+ struct mcast_handler_args *grp = arg;
+ struct nlattr *tb[CTRL_ATTR_MAX + 1];
+ struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
+ struct nlattr *mcgrp;
+ int rem_mcgrp;
+
+ nla_parse(tb, CTRL_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
+ genlmsg_attrlen(gnlh, 0), NULL);
+
+ if (!tb[CTRL_ATTR_MCAST_GROUPS])
+ return NL_SKIP;
+
+ nla_for_each_nested(mcgrp, tb[CTRL_ATTR_MCAST_GROUPS], rem_mcgrp) {
+ struct nlattr *tb_mcgrp[CTRL_ATTR_MCAST_GRP_MAX + 1];
+
+ nla_parse(tb_mcgrp, CTRL_ATTR_MCAST_GRP_MAX,
+ nla_data(mcgrp), nla_len(mcgrp), NULL);
+
+ if (!tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME] ||
+ !tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID])
+ continue;
+ if (strncmp(nla_data(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME]),
+ grp->group, nla_len(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME])))
+ continue;
+ grp->id = nla_get_u32(tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID]);
+ break;
+ }
+
+ return NL_SKIP;
+}
+
+static int mcast_error_handler(struct sockaddr_nl (*nla)__always_unused,
+ struct nlmsgerr *err, void *arg)
+{
+ int *ret = arg;
+
+ *ret = err->error;
+ return NL_STOP;
+}
+
+static int mcast_ack_handler(struct nl_msg (*msg)__always_unused, void *arg)
+{
+ int *ret = arg;
+
+ *ret = 0;
+ return NL_STOP;
+}
+
+static int ovpn_handle_msg(struct nl_msg *msg, void *arg)
+{
+ struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
+ struct nlattr *attrs[OVPN_A_MAX + 1];
+ struct nlmsghdr *nlh = nlmsg_hdr(msg);
+ //enum ovpn_del_peer_reason reason;
+ char ifname[IF_NAMESIZE];
+ int *ret = arg;
+ __u32 ifindex;
+
+ fprintf(stderr, "received message from ovpn-dco\n");
+
+ *ret = -1;
+
+ if (!genlmsg_valid_hdr(nlh, 0)) {
+ fprintf(stderr, "invalid header\n");
+ return NL_STOP;
+ }
+
+ if (nla_parse(attrs, OVPN_A_MAX, genlmsg_attrdata(gnlh, 0),
+ genlmsg_attrlen(gnlh, 0), NULL)) {
+ fprintf(stderr, "received bogus data from ovpn-dco\n");
+ return NL_STOP;
+ }
+
+ if (!attrs[OVPN_A_IFINDEX]) {
+ fprintf(stderr, "no ifindex in this message\n");
+ return NL_STOP;
+ }
+
+ ifindex = nla_get_u32(attrs[OVPN_A_IFINDEX]);
+ if (!if_indextoname(ifindex, ifname)) {
+ fprintf(stderr, "cannot resolve ifname for ifindex: %u\n",
+ ifindex);
+ return NL_STOP;
+ }
+
+ switch (gnlh->cmd) {
+ case OVPN_CMD_PEER_DEL_NTF:
+ /*if (!attrs[OVPN_A_DEL_PEER_REASON]) {
+ * fprintf(stderr, "no reason in DEL_PEER message\n");
+ * return NL_STOP;
+ *}
+ *
+ *reason = nla_get_u8(attrs[OVPN_A_DEL_PEER_REASON]);
+ *fprintf(stderr,
+ * "received CMD_DEL_PEER, ifname: %s reason: %d\n",
+ * ifname, reason);
+ */
+ fprintf(stdout, "received CMD_PEER_DEL_NTF\n");
+ break;
+ case OVPN_CMD_KEY_SWAP_NTF:
+ fprintf(stdout, "received CMD_KEY_SWAP_NTF\n");
+ break;
+ default:
+ fprintf(stderr, "received unknown command: %d\n", gnlh->cmd);
+ return NL_STOP;
+ }
+
+ *ret = 0;
+ return NL_OK;
+}
+
+static int ovpn_get_mcast_id(struct nl_sock *sock, const char *family,
+ const char *group)
+{
+ struct nl_msg *msg;
+ struct nl_cb *cb;
+ int ret, ctrlid;
+ struct mcast_handler_args grp = {
+ .group = group,
+ .id = -ENOENT,
+ };
+
+ msg = nlmsg_alloc();
+ if (!msg)
+ return -ENOMEM;
+
+ cb = nl_cb_alloc(NL_CB_DEFAULT);
+ if (!cb) {
+ ret = -ENOMEM;
+ goto out_fail_cb;
+ }
+
+ ctrlid = genl_ctrl_resolve(sock, "nlctrl");
+
+ genlmsg_put(msg, 0, 0, ctrlid, 0, 0, CTRL_CMD_GETFAMILY, 0);
+
+ ret = -ENOBUFS;
+ NLA_PUT_STRING(msg, CTRL_ATTR_FAMILY_NAME, family);
+
+ ret = nl_send_auto_complete(sock, msg);
+ if (ret < 0)
+ goto nla_put_failure;
+
+ ret = 1;
+
+ nl_cb_err(cb, NL_CB_CUSTOM, mcast_error_handler, &ret);
+ nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, mcast_ack_handler, &ret);
+ nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, mcast_family_handler, &grp);
+
+ while (ret > 0)
+ nl_recvmsgs(sock, cb);
+
+ if (ret == 0)
+ ret = grp.id;
+ nla_put_failure:
+ nl_cb_put(cb);
+ out_fail_cb:
+ nlmsg_free(msg);
+ return ret;
+}
+
+static int ovpn_listen_mcast(void)
+{
+ struct nl_sock *sock;
+ struct nl_cb *cb;
+ int mcid, ret;
+
+ sock = nl_socket_alloc();
+ if (!sock) {
+ fprintf(stderr, "cannot allocate netlink socket\n");
+ goto err_free;
+ }
+
+ nl_socket_set_buffer_size(sock, 8192, 8192);
+
+ ret = genl_connect(sock);
+ if (ret < 0) {
+ fprintf(stderr, "cannot connect to generic netlink: %s\n",
+ nl_geterror(ret));
+ goto err_free;
+ }
+
+ mcid = ovpn_get_mcast_id(sock, OVPN_FAMILY_NAME, OVPN_MCGRP_PEERS);
+ if (mcid < 0) {
+ fprintf(stderr, "cannot get mcast group: %s\n",
+ nl_geterror(mcid));
+ goto err_free;
+ }
+
+ ret = nl_socket_add_membership(sock, mcid);
+ if (ret) {
+ fprintf(stderr, "failed to join mcast group: %d\n", ret);
+ goto err_free;
+ }
+
+ ret = 1;
+ cb = nl_cb_alloc(NL_CB_DEFAULT);
+ nl_cb_set(cb, NL_CB_SEQ_CHECK, NL_CB_CUSTOM, nl_seq_check, NULL);
+ nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, ovpn_handle_msg, &ret);
+ nl_cb_err(cb, NL_CB_CUSTOM, ovpn_nl_cb_error, &ret);
+
+ while (ret == 1) {
+ int err = nl_recvmsgs(sock, cb);
+
+ if (err < 0) {
+ fprintf(stderr,
+ "cannot receive netlink message: (%d) %s\n",
+ err, nl_geterror(-err));
+ ret = -1;
+ break;
+ }
+ }
+
+ nl_cb_put(cb);
+err_free:
+ nl_socket_free(sock);
+ return ret;
+}
+
+static void usage(const char *cmd)
+{
+ fprintf(stderr,
+ "Usage %s <command> <iface> [arguments..]\n",
+ cmd);
+ fprintf(stderr, "where <command> can be one of the following\n\n");
+
+ fprintf(stderr, "* new_iface <iface> [mode]: create new ovpn interface\n");
+ fprintf(stderr, "\tiface: ovpn interface name\n");
+ fprintf(stderr, "\tmode:\n");
+ fprintf(stderr, "\t\t- P2P for peer-to-peer mode (i.e. client)\n");
+ fprintf(stderr, "\t\t- MP for multi-peer mode (i.e. server)\n");
+
+ fprintf(stderr, "* del_iface <iface>: delete ovpn interface\n");
+ fprintf(stderr, "\tiface: ovpn interface name\n");
+
+ fprintf(stderr,
+ "* listen <iface> <lport> <peers_file> [ipv6]: listen for incoming peer TCP connections\n");
+ fprintf(stderr, "\tiface: ovpn interface name\n");
+ fprintf(stderr, "\tlport: TCP port to listen to\n");
+ fprintf(stderr,
+ "\tpeers_file: file containing one peer per line: Line format:\n");
+ fprintf(stderr, "\t\t<peer_id> <vpnaddr>\n");
+ fprintf(stderr,
+ "\tipv6: whether the socket should listen to the IPv6 wildcard address\n");
+
+ fprintf(stderr,
+ "* connect <iface> <peer_id> <raddr> <rport> [key_file]: start connecting peer of TCP-based VPN session\n");
+ fprintf(stderr, "\tiface: ovpn interface name\n");
+ fprintf(stderr, "\tpeer_id: peer ID of the connecting peer\n");
+ fprintf(stderr, "\traddr: peer IP address to connect to\n");
+ fprintf(stderr, "\trport: peer TCP port to connect to\n");
+ fprintf(stderr,
+ "\tkey_file: file containing the symmetric key for encryption\n");
+
+ fprintf(stderr,
+ "* new_peer <iface> <peer_id> <lport> <raddr> <rport> [vpnaddr]: add new peer\n");
+ fprintf(stderr, "\tiface: ovpn interface name\n");
+ fprintf(stderr, "\tlport: local UDP port to bind to\n");
+ fprintf(stderr,
+ "\tpeer_id: peer ID to be used in data packets to/from this peer\n");
+ fprintf(stderr, "\traddr: peer IP address\n");
+ fprintf(stderr, "\trport: peer UDP port\n");
+ fprintf(stderr, "\tvpnaddr: peer VPN IP\n");
+
+ fprintf(stderr,
+ "* new_multi_peer <iface> <lport> <peers_file>: add multiple peers as listed in the file\n");
+ fprintf(stderr, "\tiface: ovpn interface name\n");
+ fprintf(stderr, "\tlport: local UDP port to bind to\n");
+ fprintf(stderr,
+ "\tpeers_file: text file containing one peer per line. Line format:\n");
+ fprintf(stderr, "\t\t<peer_id> <raddr> <rport> <vpnaddr>\n");
+
+ fprintf(stderr,
+ "* set_peer <iface> <peer_id> <keepalive_interval> <keepalive_timeout>: set peer attributes\n");
+ fprintf(stderr, "\tiface: ovpn interface name\n");
+ fprintf(stderr, "\tpeer_id: peer ID of the peer to modify\n");
+ fprintf(stderr,
+ "\tkeepalive_interval: interval for sending ping messages\n");
+ fprintf(stderr,
+ "\tkeepalive_timeout: time after which a peer is timed out\n");
+
+ fprintf(stderr, "* del_peer <iface> <peer_id>: delete peer\n");
+ fprintf(stderr, "\tiface: ovpn interface name\n");
+ fprintf(stderr, "\tpeer_id: peer ID of the peer to delete\n");
+
+ fprintf(stderr, "* get_peer <iface> [peer_id]: retrieve peer(s) status\n");
+ fprintf(stderr, "\tiface: ovpn interface name\n");
+ fprintf(stderr,
+ "\tpeer_id: peer ID of the peer to query. All peers are returned if omitted\n");
+
+ fprintf(stderr,
+ "* new_key <iface> <peer_id> <slot> <key_id> <cipher> <key_dir> <key_file>: set data channel key\n");
+ fprintf(stderr, "\tiface: ovpn interface name\n");
+ fprintf(stderr,
+ "\tpeer_id: peer ID of the peer to configure the key for\n");
+ fprintf(stderr, "\tslot: either 1 (primary) or 2 (secondary)\n");
+ fprintf(stderr, "\tkey_id: an ID from 0 to 7\n");
+ fprintf(stderr,
+ "\tcipher: cipher to use, supported: aes (AES-GCM), chachapoly (CHACHA20POLY1305)\n");
+ fprintf(stderr,
+ "\tkey_dir: key direction, must 0 on one host and 1 on the other\n");
+ fprintf(stderr, "\tkey_file: file containing the pre-shared key\n");
+
+ fprintf(stderr,
+ "* del_key <iface> <peer_id> [slot]: erase existing data channel key\n");
+ fprintf(stderr, "\tiface: ovpn interface name\n");
+ fprintf(stderr, "\tpeer_id: peer ID of the peer to modify\n");
+ fprintf(stderr, "\tslot: slot to erase. PRIMARY if omitted\n");
+
+ fprintf(stderr,
+ "* get_key <iface> <peer_id> <slot>: retrieve non sensible key data\n");
+ fprintf(stderr, "\tiface: ovpn interface name\n");
+ fprintf(stderr, "\tpeer_id: peer ID of the peer to query\n");
+ fprintf(stderr, "\tslot: either 1 (primary) or 2 (secondary)\n");
+
+ fprintf(stderr,
+ "* swap_keys <iface> <peer_id>: swap content of primary and secondary key slots\n");
+ fprintf(stderr, "\tiface: ovpn interface name\n");
+ fprintf(stderr, "\tpeer_id: peer ID of the peer to modify\n");
+
+ fprintf(stderr,
+ "* listen_mcast: listen to ovpn netlink multicast messages\n");
+}
+
+static int ovpn_parse_remote(struct ovpn_ctx *ovpn, const char *host,
+ const char *service, const char *vpnip)
+{
+ int ret;
+ struct addrinfo *result;
+ struct addrinfo hints = {
+ .ai_family = ovpn->sa_family,
+ .ai_socktype = SOCK_DGRAM,
+ .ai_protocol = IPPROTO_UDP
+ };
+
+ if (host) {
+ ret = getaddrinfo(host, service, &hints, &result);
+ if (ret == EAI_NONAME || ret == EAI_FAIL)
+ return -1;
+
+ if (!(result->ai_family == AF_INET &&
+ result->ai_addrlen == sizeof(struct sockaddr_in)) &&
+ !(result->ai_family == AF_INET6 &&
+ result->ai_addrlen == sizeof(struct sockaddr_in6))) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ memcpy(&ovpn->remote, result->ai_addr, result->ai_addrlen);
+ }
+
+ if (vpnip) {
+ ret = getaddrinfo(vpnip, NULL, &hints, &result);
+ if (ret == EAI_NONAME || ret == EAI_FAIL)
+ return -1;
+
+ if (!(result->ai_family == AF_INET &&
+ result->ai_addrlen == sizeof(struct sockaddr_in)) &&
+ !(result->ai_family == AF_INET6 &&
+ result->ai_addrlen == sizeof(struct sockaddr_in6))) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ memcpy(&ovpn->peer_ip, result->ai_addr, result->ai_addrlen);
+ ovpn->sa_family = result->ai_family;
+
+ ovpn->peer_ip_set = true;
+ }
+
+ ret = 0;
+out:
+ freeaddrinfo(result);
+ return ret;
+}
+
+static int ovpn_parse_new_peer(struct ovpn_ctx *ovpn, const char *peer_id,
+ const char *raddr, const char *rport,
+ const char *vpnip)
+{
+ ovpn->peer_id = strtoul(peer_id, NULL, 10);
+ if (errno == ERANGE || ovpn->peer_id > PEER_ID_UNDEF) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+
+ return ovpn_parse_remote(ovpn, raddr, rport, vpnip);
+}
+
+static int ovpn_parse_key_slot(const char *arg, struct ovpn_ctx *ovpn)
+{
+ int slot = strtoul(arg, NULL, 10);
+
+ if (errno == ERANGE || slot < 1 || slot > 2) {
+ fprintf(stderr, "key slot out of range\n");
+ return -1;
+ }
+
+ switch (slot) {
+ case 1:
+ ovpn->key_slot = OVPN_KEY_SLOT_PRIMARY;
+ break;
+ case 2:
+ ovpn->key_slot = OVPN_KEY_SLOT_SECONDARY;
+ break;
+ }
+
+ return 0;
+}
+
+static int ovpn_send_tcp_data(int socket)
+{
+ uint16_t len = htons(1000);
+ uint8_t buf[1002];
+ int ret;
+
+ memcpy(buf, &len, sizeof(len));
+ memset(buf + sizeof(len), 0x86, sizeof(buf) - sizeof(len));
+
+ ret = send(socket, buf, sizeof(buf), MSG_NOSIGNAL);
+
+ fprintf(stdout, "Sent %u bytes over TCP socket\n", ret);
+
+ return ret > 0 ? 0 : ret;
+}
+
+static int ovpn_recv_tcp_data(int socket)
+{
+ uint8_t buf[1002];
+ uint16_t len;
+ int ret;
+
+ ret = recv(socket, buf, sizeof(buf), MSG_NOSIGNAL);
+
+ if (ret < 2) {
+ fprintf(stderr, ">>>> Error while reading TCP data: %d\n", ret);
+ return ret;
+ }
+
+ memcpy(&len, buf, sizeof(len));
+ len = ntohs(len);
+
+ fprintf(stdout, ">>>> Received %u bytes over TCP socket, header: %u\n",
+ ret, len);
+
+/* int i;
+ * for (i = 2; i < ret; i++) {
+ * fprintf(stdout, "0x%.2x ", buf[i]);
+ * if (i && !((i - 2) % 16))
+ * fprintf(stdout, "\n");
+ * }
+ * fprintf(stdout, "\n");
+ */
+ return 0;
+}
+
+static enum ovpn_cmd ovpn_parse_cmd(const char *cmd)
+{
+ if (!strcmp(cmd, "new_iface"))
+ return CMD_NEW_IFACE;
+
+ if (!strcmp(cmd, "del_iface"))
+ return CMD_DEL_IFACE;
+
+ if (!strcmp(cmd, "listen"))
+ return CMD_LISTEN;
+
+ if (!strcmp(cmd, "connect"))
+ return CMD_CONNECT;
+
+ if (!strcmp(cmd, "new_peer"))
+ return CMD_NEW_PEER;
+
+ if (!strcmp(cmd, "new_multi_peer"))
+ return CMD_NEW_MULTI_PEER;
+
+ if (!strcmp(cmd, "set_peer"))
+ return CMD_SET_PEER;
+
+ if (!strcmp(cmd, "del_peer"))
+ return CMD_DEL_PEER;
+
+ if (!strcmp(cmd, "get_peer"))
+ return CMD_GET_PEER;
+
+ if (!strcmp(cmd, "new_key"))
+ return CMD_NEW_KEY;
+
+ if (!strcmp(cmd, "del_key"))
+ return CMD_DEL_KEY;
+
+ if (!strcmp(cmd, "get_key"))
+ return CMD_GET_KEY;
+
+ if (!strcmp(cmd, "swap_keys"))
+ return CMD_SWAP_KEYS;
+
+ if (!strcmp(cmd, "listen_mcast"))
+ return CMD_LISTEN_MCAST;
+
+ return CMD_INVALID;
+}
+
+/* Send process to background and waits for signal.
+ *
+ * This helper is called at the end of commands
+ * creating sockets, so that the latter stay alive
+ * along with the process that created them.
+ *
+ * A signal is expected to be delivered in order to
+ * terminate the waiting processes
+ */
+static void ovpn_waitbg(void)
+{
+ daemon(1, 1);
+ pause();
+}
+
+static int ovpn_run_cmd(struct ovpn_ctx *ovpn)
+{
+ char peer_id[10], vpnip[INET6_ADDRSTRLEN], raddr[128], rport[10];
+ int n, ret;
+ FILE *fp;
+
+ switch (ovpn->cmd) {
+ case CMD_NEW_IFACE:
+ ret = ovpn_new_iface(ovpn);
+ break;
+ case CMD_DEL_IFACE:
+ ret = ovpn_del_iface(ovpn);
+ break;
+ case CMD_LISTEN:
+ ret = ovpn_listen(ovpn, ovpn->sa_family);
+ if (ret < 0) {
+ fprintf(stderr, "cannot listen on TCP socket\n");
+ return ret;
+ }
+
+ fp = fopen(ovpn->peers_file, "r");
+ if (!fp) {
+ fprintf(stderr, "cannot open file: %s\n",
+ ovpn->peers_file);
+ return -1;
+ }
+
+ int num_peers = 0;
+
+ while ((n = fscanf(fp, "%s %s\n", peer_id, vpnip)) == 2) {
+ struct ovpn_ctx peer_ctx = { 0 };
+
+ if (num_peers == MAX_PEERS) {
+ fprintf(stderr, "max peers reached!\n");
+ return -E2BIG;
+ }
+
+ peer_ctx.ifindex = ovpn->ifindex;
+ peer_ctx.sa_family = ovpn->sa_family;
+
+ peer_ctx.socket = ovpn_accept(ovpn);
+ if (peer_ctx.socket < 0) {
+ fprintf(stderr, "cannot accept connection!\n");
+ return -1;
+ }
+
+ /* store peer sockets to test TCP I/O */
+ ovpn->cli_sockets[num_peers] = peer_ctx.socket;
+
+ ret = ovpn_parse_new_peer(&peer_ctx, peer_id, NULL,
+ NULL, vpnip);
+ if (ret < 0) {
+ fprintf(stderr, "error while parsing line\n");
+ return -1;
+ }
+
+ ret = ovpn_new_peer(&peer_ctx, true);
+ if (ret < 0) {
+ fprintf(stderr,
+ "cannot add peer to VPN: %s %s\n",
+ peer_id, vpnip);
+ return ret;
+ }
+ num_peers++;
+ }
+
+ for (int i = 0; i < num_peers; i++) {
+ ret = ovpn_recv_tcp_data(ovpn->cli_sockets[i]);
+ if (ret < 0)
+ break;
+ }
+ ovpn_waitbg();
+ break;
+ case CMD_CONNECT:
+ ret = ovpn_connect(ovpn);
+ if (ret < 0) {
+ fprintf(stderr, "cannot connect TCP socket\n");
+ return ret;
+ }
+
+ ret = ovpn_new_peer(ovpn, true);
+ if (ret < 0) {
+ fprintf(stderr, "cannot add peer to VPN\n");
+ close(ovpn->socket);
+ return ret;
+ }
+
+ if (ovpn->cipher != OVPN_CIPHER_ALG_NONE) {
+ ret = ovpn_new_key(ovpn);
+ if (ret < 0) {
+ fprintf(stderr, "cannot set key\n");
+ return ret;
+ }
+ }
+
+ ret = ovpn_send_tcp_data(ovpn->socket);
+ ovpn_waitbg();
+ break;
+ case CMD_NEW_PEER:
+ ret = ovpn_udp_socket(ovpn, AF_INET6); //ovpn->sa_family ?
+ if (ret < 0)
+ return ret;
+
+ ret = ovpn_new_peer(ovpn, false);
+ ovpn_waitbg();
+ break;
+ case CMD_NEW_MULTI_PEER:
+ ret = ovpn_udp_socket(ovpn, AF_INET6);
+ if (ret < 0)
+ return ret;
+
+ fp = fopen(ovpn->peers_file, "r");
+ if (!fp) {
+ fprintf(stderr, "cannot open file: %s\n",
+ ovpn->peers_file);
+ return -1;
+ }
+
+ while ((n = fscanf(fp, "%s %s %s %s\n", peer_id, raddr, rport,
+ vpnip)) == 4) {
+ struct ovpn_ctx peer_ctx = { 0 };
+
+ peer_ctx.ifindex = ovpn->ifindex;
+ peer_ctx.socket = ovpn->socket;
+ peer_ctx.sa_family = AF_UNSPEC;
+
+ ret = ovpn_parse_new_peer(&peer_ctx, peer_id, raddr,
+ rport, vpnip);
+ if (ret < 0) {
+ fprintf(stderr, "error while parsing line\n");
+ return -1;
+ }
+
+ ret = ovpn_new_peer(&peer_ctx, false);
+ if (ret < 0) {
+ fprintf(stderr,
+ "cannot add peer to VPN: %s %s %s %s\n",
+ peer_id, raddr, rport, vpnip);
+ return ret;
+ }
+ }
+ ovpn_waitbg();
+ break;
+ case CMD_SET_PEER:
+ ret = ovpn_set_peer(ovpn);
+ break;
+ case CMD_DEL_PEER:
+ ret = ovpn_del_peer(ovpn);
+ break;
+ case CMD_GET_PEER:
+ if (ovpn->peer_id == PEER_ID_UNDEF)
+ fprintf(stderr, "List of peers connected to: %s\n",
+ ovpn->ifname);
+
+ ret = ovpn_get_peer(ovpn);
+ break;
+ case CMD_NEW_KEY:
+ ret = ovpn_new_key(ovpn);
+ break;
+ case CMD_DEL_KEY:
+ ret = ovpn_del_key(ovpn);
+ break;
+ case CMD_GET_KEY:
+ ret = ovpn_get_key(ovpn);
+ break;
+ case CMD_SWAP_KEYS:
+ ret = ovpn_swap_keys(ovpn);
+ break;
+ case CMD_LISTEN_MCAST:
+ ret = ovpn_listen_mcast();
+ break;
+ case CMD_INVALID:
+ break;
+ }
+
+ return ret;
+}
+
+static int ovpn_parse_cmd_args(struct ovpn_ctx *ovpn, int argc, char *argv[])
+{
+ int ret;
+
+ /* no args required for LISTEN_MCAST */
+ if (ovpn->cmd == CMD_LISTEN_MCAST)
+ return 0;
+
+ /* all commands need an ifname */
+ if (argc < 3)
+ return -EINVAL;
+
+ strscpy(ovpn->ifname, argv[2], IFNAMSIZ - 1);
+ ovpn->ifname[IFNAMSIZ - 1] = '\0';
+
+ /* all commands, except NEW_IFNAME, needs an ifindex */
+ if (ovpn->cmd != CMD_NEW_IFACE) {
+ ovpn->ifindex = if_nametoindex(ovpn->ifname);
+ if (!ovpn->ifindex) {
+ fprintf(stderr, "cannot find interface: %s\n",
+ strerror(errno));
+ return -1;
+ }
+ }
+
+ switch (ovpn->cmd) {
+ case CMD_NEW_IFACE:
+ if (argc < 4)
+ break;
+
+ if (!strcmp(argv[3], "P2P")) {
+ ovpn->mode = OVPN_MODE_P2P;
+ } else if (!strcmp(argv[3], "MP")) {
+ ovpn->mode = OVPN_MODE_MP;
+ } else {
+ fprintf(stderr, "Cannot parse iface mode: %s\n",
+ argv[3]);
+ return -1;
+ }
+ ovpn->mode_set = true;
+ break;
+ case CMD_DEL_IFACE:
+ break;
+ case CMD_LISTEN:
+ if (argc < 5)
+ return -EINVAL;
+
+ ovpn->lport = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE || ovpn->lport > 65535) {
+ fprintf(stderr, "lport value out of range\n");
+ return -1;
+ }
+
+ ovpn->peers_file = argv[4];
+
+ if (argc > 5 && !strcmp(argv[5], "ipv6"))
+ ovpn->sa_family = AF_INET6;
+ break;
+ case CMD_CONNECT:
+ if (argc < 6)
+ return -EINVAL;
+
+ ovpn->sa_family = AF_INET;
+
+ ret = ovpn_parse_new_peer(ovpn, argv[3], argv[4], argv[5],
+ NULL);
+ if (ret < 0) {
+ fprintf(stderr, "Cannot parse remote peer data\n");
+ return -1;
+ }
+
+ if (argc > 6) {
+ ovpn->key_slot = OVPN_KEY_SLOT_PRIMARY;
+ ovpn->key_id = 0;
+ ovpn->cipher = OVPN_CIPHER_ALG_AES_GCM;
+ ovpn->key_dir = KEY_DIR_OUT;
+
+ ret = ovpn_parse_key(argv[6], ovpn);
+ if (ret)
+ return -1;
+ }
+ break;
+ case CMD_NEW_PEER:
+ if (argc < 7)
+ return -EINVAL;
+
+ ovpn->lport = strtoul(argv[4], NULL, 10);
+ if (errno == ERANGE || ovpn->lport > 65535) {
+ fprintf(stderr, "lport value out of range\n");
+ return -1;
+ }
+
+ const char *vpnip = (argc > 7) ? argv[7] : NULL;
+
+ ret = ovpn_parse_new_peer(ovpn, argv[3], argv[5], argv[6],
+ vpnip);
+ if (ret < 0)
+ return -1;
+ break;
+ case CMD_NEW_MULTI_PEER:
+ if (argc < 5)
+ return -EINVAL;
+
+ ovpn->lport = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE || ovpn->lport > 65535) {
+ fprintf(stderr, "lport value out of range\n");
+ return -1;
+ }
+
+ ovpn->peers_file = argv[4];
+ break;
+ case CMD_SET_PEER:
+ if (argc < 6)
+ return -EINVAL;
+
+ ovpn->peer_id = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE || ovpn->peer_id > PEER_ID_UNDEF) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+
+ ovpn->keepalive_interval = strtoul(argv[4], NULL, 10);
+ if (errno == ERANGE) {
+ fprintf(stderr,
+ "keepalive interval value out of range\n");
+ return -1;
+ }
+
+ ovpn->keepalive_timeout = strtoul(argv[5], NULL, 10);
+ if (errno == ERANGE) {
+ fprintf(stderr,
+ "keepalive interval value out of range\n");
+ return -1;
+ }
+ break;
+ case CMD_DEL_PEER:
+ if (argc < 4)
+ return -EINVAL;
+
+ ovpn->peer_id = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE || ovpn->peer_id > PEER_ID_UNDEF) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+ break;
+ case CMD_GET_PEER:
+ ovpn->peer_id = PEER_ID_UNDEF;
+ if (argc > 3) {
+ ovpn->peer_id = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE || ovpn->peer_id > PEER_ID_UNDEF) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+ }
+ break;
+ case CMD_NEW_KEY:
+ if (argc < 9)
+ return -EINVAL;
+
+ ovpn->peer_id = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+
+ ret = ovpn_parse_key_slot(argv[4], ovpn);
+ if (ret)
+ return -1;
+
+ ovpn->key_id = strtoul(argv[5], NULL, 10);
+ if (errno == ERANGE || ovpn->key_id > 2) {
+ fprintf(stderr, "key ID out of range\n");
+ return -1;
+ }
+
+ ret = ovpn_parse_cipher(argv[6], ovpn);
+ if (ret < 0)
+ return -1;
+
+ ret = ovpn_parse_key_direction(argv[7], ovpn);
+ if (ret < 0)
+ return -1;
+
+ ret = ovpn_parse_key(argv[8], ovpn);
+ if (ret)
+ return -1;
+ break;
+ case CMD_DEL_KEY:
+ if (argc < 4)
+ return -EINVAL;
+
+ ovpn->peer_id = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+
+ ret = ovpn_parse_key_slot(argv[4], ovpn);
+ if (ret)
+ return ret;
+ break;
+ case CMD_GET_KEY:
+ if (argc < 5)
+ return -EINVAL;
+
+ ovpn->peer_id = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+
+ ret = ovpn_parse_key_slot(argv[4], ovpn);
+ if (ret)
+ return ret;
+ break;
+ case CMD_SWAP_KEYS:
+ if (argc < 4)
+ return -EINVAL;
+
+ ovpn->peer_id = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+ break;
+ case CMD_LISTEN_MCAST:
+ break;
+ case CMD_INVALID:
+ break;
+ }
+
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ struct ovpn_ctx ovpn;
+ int ret;
+
+ if (argc < 2) {
+ usage(argv[0]);
+ return -1;
+ }
+
+ memset(&ovpn, 0, sizeof(ovpn));
+ ovpn.sa_family = AF_INET;
+ ovpn.cipher = OVPN_CIPHER_ALG_NONE;
+
+ ovpn.cmd = ovpn_parse_cmd(argv[1]);
+ if (ovpn.cmd == CMD_INVALID) {
+ fprintf(stderr, "Error: unknown command.\n\n");
+ usage(argv[0]);
+ return -1;
+ }
+
+ ret = ovpn_parse_cmd_args(&ovpn, argc, argv);
+ if (ret < 0) {
+ fprintf(stderr, "Error: invalid arguments.\n\n");
+ if (ret == -EINVAL)
+ usage(argv[0]);
+ return ret;
+ }
+
+ ret = ovpn_run_cmd(&ovpn);
+ if (ret)
+ fprintf(stderr, "Cannot execute command: %s (%d)\n",
+ strerror(-ret), ret);
+
+ return ret;
+}
diff --git a/tools/testing/selftests/net/ovpn/tcp_peers.txt b/tools/testing/selftests/net/ovpn/tcp_peers.txt
new file mode 100644
index 0000000000000000000000000000000000000000..d753eebe8716ed3588334ad766981e883ed2469a
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/tcp_peers.txt
@@ -0,0 +1,5 @@
+1 5.5.5.2
+2 5.5.5.3
+3 5.5.5.4
+4 5.5.5.5
+5 5.5.5.6
diff --git a/tools/testing/selftests/net/ovpn/test-chachapoly.sh b/tools/testing/selftests/net/ovpn/test-chachapoly.sh
new file mode 100755
index 0000000000000000000000000000000000000000..32504079a2b894c3b700538772493a5c74139cd6
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/test-chachapoly.sh
@@ -0,0 +1,9 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2025 OpenVPN, Inc.
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+
+ALG="chachapoly"
+
+source test.sh
diff --git a/tools/testing/selftests/net/ovpn/test-close-socket-tcp.sh b/tools/testing/selftests/net/ovpn/test-close-socket-tcp.sh
new file mode 100755
index 0000000000000000000000000000000000000000..093d44772ffdf5aa8d0aa5505c21cb2c77a70aa0
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/test-close-socket-tcp.sh
@@ -0,0 +1,9 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2025 OpenVPN, Inc.
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+
+PROTO="TCP"
+
+source test-close-socket.sh
diff --git a/tools/testing/selftests/net/ovpn/test-close-socket.sh b/tools/testing/selftests/net/ovpn/test-close-socket.sh
new file mode 100755
index 0000000000000000000000000000000000000000..5e48a8b67928770daecc7b7d7f877a542a97743e
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/test-close-socket.sh
@@ -0,0 +1,45 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2020-2025 OpenVPN, Inc.
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+
+#set -x
+set -e
+
+source ./common.sh
+
+cleanup
+
+modprobe -q ovpn || true
+
+for p in $(seq 0 ${NUM_PEERS}); do
+ create_ns ${p}
+done
+
+for p in $(seq 0 ${NUM_PEERS}); do
+ setup_ns ${p} 5.5.5.$((${p} + 1))/24
+done
+
+for p in $(seq 0 ${NUM_PEERS}); do
+ add_peer ${p}
+done
+
+for p in $(seq 1 ${NUM_PEERS}); do
+ ip netns exec peer0 ${OVPN_CLI} set_peer tun0 ${p} 60 120
+ ip netns exec peer${p} ${OVPN_CLI} set_peer tun${p} ${p} 60 120
+done
+
+sleep 1
+
+for p in $(seq 1 ${NUM_PEERS}); do
+ ip netns exec peer0 ping -qfc 500 -w 3 5.5.5.$((${p} + 1))
+done
+
+ip netns exec peer0 iperf3 -1 -s &
+sleep 1
+ip netns exec peer1 iperf3 -Z -t 3 -c 5.5.5.1
+
+cleanup
+
+modprobe -r ovpn || true
diff --git a/tools/testing/selftests/net/ovpn/test-float.sh b/tools/testing/selftests/net/ovpn/test-float.sh
new file mode 100755
index 0000000000000000000000000000000000000000..ba5d725e18b074ac4cac6d160cce4e64fa4f6867
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/test-float.sh
@@ -0,0 +1,9 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2025 OpenVPN, Inc.
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+
+FLOAT="1"
+
+source test.sh
diff --git a/tools/testing/selftests/net/ovpn/test-tcp.sh b/tools/testing/selftests/net/ovpn/test-tcp.sh
new file mode 100755
index 0000000000000000000000000000000000000000..ba3f1f315a349cf6f20c9035cf69816b590f91ab
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/test-tcp.sh
@@ -0,0 +1,9 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2025 OpenVPN, Inc.
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+
+PROTO="TCP"
+
+source test.sh
diff --git a/tools/testing/selftests/net/ovpn/test.sh b/tools/testing/selftests/net/ovpn/test.sh
new file mode 100755
index 0000000000000000000000000000000000000000..7b62897b024084a52e18e67be3b9ec1a736316e4
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/test.sh
@@ -0,0 +1,113 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2020-2025 OpenVPN, Inc.
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+
+#set -x
+set -e
+
+source ./common.sh
+
+cleanup
+
+modprobe -q ovpn || true
+
+for p in $(seq 0 ${NUM_PEERS}); do
+ create_ns ${p}
+done
+
+for p in $(seq 0 ${NUM_PEERS}); do
+ setup_ns ${p} 5.5.5.$((${p} + 1))/24
+done
+
+for p in $(seq 0 ${NUM_PEERS}); do
+ add_peer ${p}
+done
+
+for p in $(seq 1 ${NUM_PEERS}); do
+ ip netns exec peer0 ${OVPN_CLI} set_peer tun0 ${p} 60 120
+ ip netns exec peer${p} ${OVPN_CLI} set_peer tun${p} ${p} 60 120
+done
+
+sleep 1
+
+for p in $(seq 1 ${NUM_PEERS}); do
+ ip netns exec peer0 ping -qfc 500 -w 3 5.5.5.$((${p} + 1))
+done
+
+if [ "$FLOAT" == "1" ]; then
+ # make clients float..
+ for p in $(seq 1 ${NUM_PEERS}); do
+ ip -n peer${p} addr del 10.10.${p}.2/24 dev veth${p}
+ ip -n peer${p} addr add 10.10.${p}.3/24 dev veth${p}
+ done
+ for p in $(seq 1 ${NUM_PEERS}); do
+ ip netns exec peer${p} ping -qfc 500 -w 3 5.5.5.1
+ done
+fi
+
+ip netns exec peer0 iperf3 -1 -s &
+sleep 1
+ip netns exec peer1 iperf3 -Z -t 3 -c 5.5.5.1
+
+echo "Adding secondary key and then swap:"
+for p in $(seq 1 ${NUM_PEERS}); do
+ ip netns exec peer0 ${OVPN_CLI} new_key tun0 ${p} 2 1 ${ALG} 0 data64.key
+ ip netns exec peer${p} ${OVPN_CLI} new_key tun${p} ${p} 2 1 ${ALG} 1 data64.key
+ ip netns exec peer${p} ${OVPN_CLI} swap_keys tun${p} ${p}
+done
+
+sleep 1
+
+echo "Querying all peers:"
+ip netns exec peer0 ${OVPN_CLI} get_peer tun0
+ip netns exec peer1 ${OVPN_CLI} get_peer tun1
+
+echo "Querying peer 1:"
+ip netns exec peer0 ${OVPN_CLI} get_peer tun0 1
+
+echo "Querying non-existent peer 10:"
+ip netns exec peer0 ${OVPN_CLI} get_peer tun0 10 || true
+
+echo "Deleting peer 1:"
+ip netns exec peer0 ${OVPN_CLI} del_peer tun0 1
+ip netns exec peer1 ${OVPN_CLI} del_peer tun1 1
+
+echo "Querying keys:"
+for p in $(seq 2 ${NUM_PEERS}); do
+ ip netns exec peer${p} ${OVPN_CLI} get_key tun${p} ${p} 1
+ ip netns exec peer${p} ${OVPN_CLI} get_key tun${p} ${p} 2
+done
+
+echo "Deleting peer while sending traffic:"
+(ip netns exec peer2 ping -qf -w 4 5.5.5.1)&
+sleep 2
+ip netns exec peer0 ${OVPN_CLI} del_peer tun0 2
+# following command fails in TCP mode
+# (both ends get conn reset when one peer disconnects)
+ip netns exec peer2 ${OVPN_CLI} del_peer tun2 2 || true
+
+echo "Deleting keys:"
+for p in $(seq 3 ${NUM_PEERS}); do
+ ip netns exec peer${p} ${OVPN_CLI} del_key tun${p} ${p} 1
+ ip netns exec peer${p} ${OVPN_CLI} del_key tun${p} ${p} 2
+done
+
+echo "Setting timeout to 3s MP:"
+for p in $(seq 3 ${NUM_PEERS}); do
+ ip netns exec peer0 ${OVPN_CLI} set_peer tun0 ${p} 3 3 || true
+ ip netns exec peer${p} ${OVPN_CLI} set_peer tun${p} ${p} 0 0
+done
+# wait for peers to timeout
+sleep 5
+
+echo "Setting timeout to 3s P2P:"
+for p in $(seq 3 ${NUM_PEERS}); do
+ ip netns exec peer${p} ${OVPN_CLI} set_peer tun${p} ${p} 3 3
+done
+sleep 5
+
+cleanup
+
+modprobe -r ovpn || true
diff --git a/tools/testing/selftests/net/ovpn/udp_peers.txt b/tools/testing/selftests/net/ovpn/udp_peers.txt
new file mode 100644
index 0000000000000000000000000000000000000000..32f14bd9347a63e58438311b6d880b9fef768aa2
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/udp_peers.txt
@@ -0,0 +1,5 @@
+1 10.10.1.2 1 5.5.5.2
+2 10.10.2.2 1 5.5.5.3
+3 10.10.3.2 1 5.5.5.4
+4 10.10.4.2 1 5.5.5.5
+5 10.10.5.2 1 5.5.5.6
--
2.45.3
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