* [PATCH net-next v6 01/25] netlink: add NLA_POLICY_MAX_LEN macro
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 02/25] rtnetlink: don't crash on unregister if no dellink exists Antonio Quartulli
` (23 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev
Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli, donald.hunter
Similarly to NLA_POLICY_MIN_LEN, NLA_POLICY_MAX_LEN defines a policy
with a maximum length value.
The netlink generator for YAML specs has been extended accordingly.
Cc: donald.hunter@gmail.com
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
include/net/netlink.h | 1 +
tools/net/ynl/ynl-gen-c.py | 2 ++
2 files changed, 3 insertions(+)
diff --git a/include/net/netlink.h b/include/net/netlink.h
index db6af207287c..2dc671c977ff 100644
--- a/include/net/netlink.h
+++ b/include/net/netlink.h
@@ -469,6 +469,7 @@ struct nla_policy {
.max = _len \
}
#define NLA_POLICY_MIN_LEN(_len) NLA_POLICY_MIN(NLA_BINARY, _len)
+#define NLA_POLICY_MAX_LEN(_len) NLA_POLICY_MAX(NLA_BINARY, _len)
/**
* struct nl_info - netlink source information
diff --git a/tools/net/ynl/ynl-gen-c.py b/tools/net/ynl/ynl-gen-c.py
index 717530bc9c52..3ccbb301be87 100755
--- a/tools/net/ynl/ynl-gen-c.py
+++ b/tools/net/ynl/ynl-gen-c.py
@@ -466,6 +466,8 @@ class TypeBinary(Type):
def _attr_policy(self, policy):
if 'exact-len' in self.checks:
mem = 'NLA_POLICY_EXACT_LEN(' + str(self.get_limit('exact-len')) + ')'
+ elif 'max-len' in self.checks:
+ mem = 'NLA_POLICY_MAX_LEN(' + str(self.get_limit('max-len')) + ')'
else:
mem = '{ '
if len(self.checks) == 1 and 'min-len' in self.checks:
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 02/25] rtnetlink: don't crash on unregister if no dellink exists
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 01/25] netlink: add NLA_POLICY_MAX_LEN macro Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 03/25] net: introduce OpenVPN Data Channel Offload (ovpn) Antonio Quartulli
` (22 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
rtnl_unregister_ops calls __rtnl_links_kill which calls
unconditionally ops->dellink on any related interface.
However, if a module hasn't implemented dellink, this
invocation will crash.
Add a check to avoid calling dellink when NULL and rather
invoke netdevice_unregister_queue to schedule unregistering
the device as usual.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
net/core/rtnetlink.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index cd9487a12d1a..6da4a6b598ba 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -453,8 +453,12 @@ static void __rtnl_kill_links(struct net *net, struct rtnl_link_ops *ops)
LIST_HEAD(list_kill);
for_each_netdev(net, dev) {
- if (dev->rtnl_link_ops == ops)
- ops->dellink(dev, &list_kill);
+ if (dev->rtnl_link_ops == ops) {
+ if (ops->dellink)
+ ops->dellink(dev, &list_kill);
+ else
+ unregister_netdevice_queue(dev, &list_kill);
+ }
}
unregister_netdevice_many(&list_kill);
}
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 03/25] net: introduce OpenVPN Data Channel Offload (ovpn)
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 01/25] netlink: add NLA_POLICY_MAX_LEN macro Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 02/25] rtnetlink: don't crash on unregister if no dellink exists Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-09-05 14:38 ` Sabrina Dubroca
2024-08-27 12:07 ` [PATCH net-next v6 04/25] ovpn: add basic netlink support Antonio Quartulli
` (21 subsequent siblings)
24 siblings, 1 reply; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev
Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli, 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 ae 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 | 7 +++
drivers/net/Kconfig | 13 +++++
drivers/net/Makefile | 1 +
drivers/net/ovpn/Makefile | 11 ++++
drivers/net/ovpn/io.c | 22 ++++++++
drivers/net/ovpn/io.h | 15 ++++++
drivers/net/ovpn/main.c | 109 ++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/main.h | 15 ++++++
include/uapi/linux/udp.h | 1 +
9 files changed, 194 insertions(+)
create mode 100644 drivers/net/ovpn/Makefile
create mode 100644 drivers/net/ovpn/io.c
create mode 100644 drivers/net/ovpn/io.h
create mode 100644 drivers/net/ovpn/main.c
create mode 100644 drivers/net/ovpn/main.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 30a9b9450e11..ec507d2394f6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17215,6 +17215,13 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs.git
F: Documentation/filesystems/overlayfs.rst
F: fs/overlayfs/
+OPENVPN DATA CHANNEL OFFLOAD
+M: Antonio Quartulli <antonio@openvpn.net>
+L: openvpn-devel@lists.sourceforge.net (moderated for non-subscribers)
+L: netdev@vger.kernel.org
+S: Maintained
+F: drivers/net/ovpn/
+
P54 WIRELESS DRIVER
M: Christian Lamparter <chunkeey@googlemail.com>
L: linux-wireless@vger.kernel.org
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 9920b3a68ed1..c5743288242d 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -115,6 +115,19 @@ config WIREGUARD_DEBUG
Say N here unless you know what you're doing.
+config OVPN
+ tristate "OpenVPN data channel offload"
+ depends on NET && INET
+ select NET_UDP_TUNNEL
+ select DST_CACHE
+ 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.
+
config EQUALIZER
tristate "EQL (serial line load balancing) support"
help
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 13743d0e83b5..5152b3330e28 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 000000000000..53fb197027d7
--- /dev/null
+++ b/drivers/net/ovpn/Makefile
@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# ovpn -- OpenVPN data channel offload in kernel space
+#
+# Copyright (C) 2020-2024 OpenVPN, Inc.
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+
+obj-$(CONFIG_OVPN) := ovpn.o
+ovpn-y += main.o
+ovpn-y += io.o
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
new file mode 100644
index 000000000000..ad3813419c33
--- /dev/null
+++ b/drivers/net/ovpn/io.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2024 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 000000000000..aa259be66441
--- /dev/null
+++ b/drivers/net/ovpn/io.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2024 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_OVPN_H_
+#define _NET_OVPN_OVPN_H_
+
+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
new file mode 100644
index 000000000000..8a90319e4600
--- /dev/null
+++ b/drivers/net/ovpn/main.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ * James Yonan <james@openvpn.net>
+ */
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/version.h>
+#include <net/rtnetlink.h>
+
+#include "main.h"
+#include "io.h"
+
+/* Driver info */
+#define DRV_DESCRIPTION "OpenVPN data channel offload (ovpn)"
+#define DRV_COPYRIGHT "(C) 2020-2024 OpenVPN, Inc."
+
+/**
+ * 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'
+ */
+bool ovpn_dev_is_valid(const struct net_device *dev)
+{
+ return dev->netdev_ops->ndo_start_xmit == ovpn_net_xmit;
+}
+
+/* we register with rtnl to let core know that ovpn is a virtual driver and
+ * therefore ifaces should be destroyed when exiting a netns
+ */
+static struct rtnl_link_ops ovpn_link_ops = {
+};
+
+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(DRV_DESCRIPTION);
+MODULE_AUTHOR(DRV_COPYRIGHT);
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/ovpn/main.h b/drivers/net/ovpn/main.h
new file mode 100644
index 000000000000..a3215316c49b
--- /dev/null
+++ b/drivers/net/ovpn/main.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2024 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * 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/include/uapi/linux/udp.h b/include/uapi/linux/udp.h
index 1a0fe8b151fb..f9f8ffddfd0c 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 */
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 03/25] net: introduce OpenVPN Data Channel Offload (ovpn)
2024-08-27 12:07 ` [PATCH net-next v6 03/25] net: introduce OpenVPN Data Channel Offload (ovpn) Antonio Quartulli
@ 2024-09-05 14:38 ` Sabrina Dubroca
2024-09-06 12:26 ` Antonio Quartulli
0 siblings, 1 reply; 58+ messages in thread
From: Sabrina Dubroca @ 2024-09-05 14:38 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew,
steffen.klassert, antony.antony
2024-08-27, 14:07:43 +0200, Antonio Quartulli wrote:
> diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
> index 9920b3a68ed1..c5743288242d 100644
> --- a/drivers/net/Kconfig
> +++ b/drivers/net/Kconfig
> @@ -115,6 +115,19 @@ config WIREGUARD_DEBUG
>
> Say N here unless you know what you're doing.
>
> +config OVPN
> + tristate "OpenVPN data channel offload"
> + depends on NET && INET
> + select NET_UDP_TUNNEL
> + select DST_CACHE
> + select CRYPTO
> + select CRYPTO_AES
> + select CRYPTO_GCM
> + select CRYPTO_CHACHA20POLY1305
and STREAM_PARSER for TCP encap?
> + help
> + This module enhances the performance of the OpenVPN userspace software
> + by offloading the data channel processing to kernelspace.
> +
--
Sabrina
^ permalink raw reply [flat|nested] 58+ messages in thread
* Re: [PATCH net-next v6 03/25] net: introduce OpenVPN Data Channel Offload (ovpn)
2024-09-05 14:38 ` Sabrina Dubroca
@ 2024-09-06 12:26 ` Antonio Quartulli
0 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-06 12:26 UTC (permalink / raw)
To: Sabrina Dubroca
Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew,
steffen.klassert, antony.antony
On 05/09/2024 16:38, Sabrina Dubroca wrote:
> 2024-08-27, 14:07:43 +0200, Antonio Quartulli wrote:
>> diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
>> index 9920b3a68ed1..c5743288242d 100644
>> --- a/drivers/net/Kconfig
>> +++ b/drivers/net/Kconfig
>> @@ -115,6 +115,19 @@ config WIREGUARD_DEBUG
>>
>> Say N here unless you know what you're doing.
>>
>> +config OVPN
>> + tristate "OpenVPN data channel offload"
>> + depends on NET && INET
>> + select NET_UDP_TUNNEL
>> + select DST_CACHE
>> + select CRYPTO
>> + select CRYPTO_AES
>> + select CRYPTO_GCM
>> + select CRYPTO_CHACHA20POLY1305
>
> and STREAM_PARSER for TCP encap?
Right, thanks!
>
>> + help
>> + This module enhances the performance of the OpenVPN userspace software
>> + by offloading the data channel processing to kernelspace.
>> +
>
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread
* [PATCH net-next v6 04/25] ovpn: add basic netlink support
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (2 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 03/25] net: introduce OpenVPN Data Channel Offload (ovpn) Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-09-06 19:26 ` Simon Horman
2024-08-27 12:07 ` [PATCH net-next v6 05/25] ovpn: add basic interface creation/destruction/management routines Antonio Quartulli
` (20 subsequent siblings)
24 siblings, 1 reply; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev
Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli, donald.hunter
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
Cc: donald.hunter@gmail.com
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
Documentation/netlink/specs/ovpn.yaml | 328 ++++++++++++++++++++++++++
MAINTAINERS | 1 +
drivers/net/ovpn/Makefile | 2 +
drivers/net/ovpn/main.c | 14 ++
drivers/net/ovpn/netlink-gen.c | 206 ++++++++++++++++
drivers/net/ovpn/netlink-gen.h | 41 ++++
drivers/net/ovpn/netlink.c | 153 ++++++++++++
drivers/net/ovpn/netlink.h | 15 ++
drivers/net/ovpn/ovpnstruct.h | 21 ++
include/uapi/linux/ovpn.h | 108 +++++++++
10 files changed, 889 insertions(+)
create mode 100644 Documentation/netlink/specs/ovpn.yaml
create mode 100644 drivers/net/ovpn/netlink-gen.c
create mode 100644 drivers/net/ovpn/netlink-gen.h
create mode 100644 drivers/net/ovpn/netlink.c
create mode 100644 drivers/net/ovpn/netlink.h
create mode 100644 drivers/net/ovpn/ovpnstruct.h
create mode 100644 include/uapi/linux/ovpn.h
diff --git a/Documentation/netlink/specs/ovpn.yaml b/Documentation/netlink/specs/ovpn.yaml
new file mode 100644
index 000000000000..456ac3747d27
--- /dev/null
+++ b/Documentation/netlink/specs/ovpn.yaml
@@ -0,0 +1,328 @@
+# SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+#
+# Copyright (c) 2024, 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
+ value-start: 0
+ entries: [ none, aes-gcm, chacha20_poly1305 ]
+ -
+ type: enum
+ name: del-peer_reason
+ value-start: 0
+ entries: [ teardown, userspace, expired, transport-error, transport_disconnect ]
+ -
+ type: enum
+ name: key-slot
+ value-start: 0
+ entries: [ primary, secondary ]
+ -
+ type: enum
+ name: mode
+ value-start: 0
+ entries: [ p2p, mp ]
+
+attribute-sets:
+ -
+ name: peer
+ attributes:
+ -
+ name: id
+ type: u32
+ doc: |
+ The unique Id of the peer. To be used to identify peers during
+ operations
+ checks:
+ max: 0xFFFFFF
+ -
+ name: sockaddr-remote
+ type: binary
+ doc: |
+ The sockaddr_in/in6 object identifying the remote address/port of the
+ peer
+ -
+ name: socket
+ type: u32
+ doc: The socket to be used to communicate with the peer
+ -
+ name: vpn-ipv4
+ type: u32
+ doc: The IPv4 assigned to the peer by the server
+ display-hint: ipv4
+ -
+ name: vpn-ipv6
+ type: binary
+ doc: The IPv6 assigned to the peer by the server
+ display-hint: ipv6
+ checks:
+ exact-len: 16
+ -
+ name: local-ip
+ type: binary
+ doc: The local IP to be used to send packets to the peer (UDP only)
+ checks:
+ max-len: 16
+ -
+ name: local-port
+ type: u32
+ doc: The local port to be used to send packets to the peer (UDP only)
+ checks:
+ min: 1
+ max: u16-max
+ -
+ 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: keyconf
+ type: nest
+ doc: Peer specific cipher configuration
+ nested-attributes: keyconf
+ -
+ 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: slot
+ type: u32
+ doc: The slot where the key should be stored
+ enum: key-slot
+ -
+ name: key-id
+ doc: |
+ The unique ID for the key. 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 actua 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 that is being created
+ -
+ name: mode
+ type: u32
+ enum: mode
+ doc: |
+ Oper mode instructing an interface to act as Point2Point or
+ MultiPoint
+ -
+ name: peer
+ type: nest
+ doc: |
+ The peer object containing the attributed of interest for the specific
+ operation
+ nested-attributes: peer
+
+operations:
+ list:
+ -
+ name: new-iface
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: Create a new interface
+ do:
+ request:
+ attributes:
+ - ifname
+ - mode
+ reply:
+ attributes:
+ - ifname
+ - ifindex
+ -
+ name: del-iface
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: Delete existing interface
+ do:
+ pre: ovpn-nl-pre-doit
+ post: ovpn-nl-post-doit
+ request:
+ attributes:
+ - ifindex
+ -
+ name: set-peer
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: Add or modify a remote peer
+ do:
+ pre: ovpn-nl-pre-doit
+ post: ovpn-nl-post-doit
+ request:
+ attributes:
+ - ifindex
+ - peer
+ -
+ name: get-peer
+ 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: del-peer
+ 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: set-key
+ attribute-set: ovpn
+ flags: [ admin-perm ]
+ doc: Add or modify a cipher key for a specific peer
+ do:
+ pre: ovpn-nl-pre-doit
+ post: ovpn-nl-post-doit
+ request:
+ attributes:
+ - ifindex
+ - peer
+ -
+ name: swap-keys
+ 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
+ - peer
+ -
+ name: del-key
+ 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
+ - peer
+
+mcast-groups:
+ list:
+ -
+ name: peers
diff --git a/MAINTAINERS b/MAINTAINERS
index ec507d2394f6..9b75356afbac 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -17221,6 +17221,7 @@ L: openvpn-devel@lists.sourceforge.net (moderated for non-subscribers)
L: netdev@vger.kernel.org
S: Maintained
F: drivers/net/ovpn/
+F: include/uapi/linux/ovpn.h
P54 WIRELESS DRIVER
M: Christian Lamparter <chunkeey@googlemail.com>
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
index 53fb197027d7..201dc001419f 100644
--- a/drivers/net/ovpn/Makefile
+++ b/drivers/net/ovpn/Makefile
@@ -9,3 +9,5 @@
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/main.c b/drivers/net/ovpn/main.c
index 8a90319e4600..7c35697cb596 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -7,12 +7,16 @@
* James Yonan <james@openvpn.net>
*/
+#include <linux/genetlink.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/version.h>
#include <net/rtnetlink.h>
+#include <uapi/linux/ovpn.h>
+#include "ovpnstruct.h"
#include "main.h"
+#include "netlink.h"
#include "io.h"
/* Driver info */
@@ -34,6 +38,7 @@ bool ovpn_dev_is_valid(const struct net_device *dev)
* therefore ifaces should be destroyed when exiting a netns
*/
static struct rtnl_link_ops ovpn_link_ops = {
+ .kind = OVPN_FAMILY_NAME,
};
static int ovpn_netdev_notifier_call(struct notifier_block *nb,
@@ -86,8 +91,16 @@ 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;
@@ -95,6 +108,7 @@ 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/netlink-gen.c b/drivers/net/ovpn/netlink-gen.c
new file mode 100644
index 000000000000..594eb2c50eb5
--- /dev/null
+++ b/drivers/net/ovpn/netlink-gen.c
@@ -0,0 +1,206 @@
+// 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_peer_local_port_range = {
+ .min = 1ULL,
+ .max = 65535ULL,
+};
+
+/* Common nested types */
+const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_DIR + 1] = {
+ [OVPN_A_KEYCONF_SLOT] = NLA_POLICY_MAX(NLA_U32, 1),
+ [OVPN_A_KEYCONF_KEY_ID] = NLA_POLICY_MAX(NLA_U32, 2),
+ [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_SOCKADDR_REMOTE] = { .type = NLA_BINARY, },
+ [OVPN_A_PEER_SOCKET] = { .type = NLA_U32, },
+ [OVPN_A_PEER_VPN_IPV4] = { .type = NLA_U32, },
+ [OVPN_A_PEER_VPN_IPV6] = NLA_POLICY_EXACT_LEN(16),
+ [OVPN_A_PEER_LOCAL_IP] = NLA_POLICY_MAX_LEN(16),
+ [OVPN_A_PEER_LOCAL_PORT] = NLA_POLICY_FULL_RANGE(NLA_U32, &ovpn_a_peer_local_port_range),
+ [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_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_nl_policy),
+ [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_NEW_IFACE - do */
+static const struct nla_policy ovpn_new_iface_nl_policy[OVPN_A_MODE + 1] = {
+ [OVPN_A_IFNAME] = { .type = NLA_NUL_STRING, },
+ [OVPN_A_MODE] = NLA_POLICY_MAX(NLA_U32, 1),
+};
+
+/* OVPN_CMD_DEL_IFACE - do */
+static const struct nla_policy ovpn_del_iface_nl_policy[OVPN_A_IFINDEX + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+};
+
+/* OVPN_CMD_SET_PEER - do */
+static const struct nla_policy ovpn_set_peer_nl_policy[OVPN_A_PEER + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+ [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy),
+};
+
+/* OVPN_CMD_GET_PEER - do */
+static const struct nla_policy ovpn_get_peer_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_GET_PEER - dump */
+static const struct nla_policy ovpn_get_peer_dump_nl_policy[OVPN_A_IFINDEX + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+};
+
+/* OVPN_CMD_DEL_PEER - do */
+static const struct nla_policy ovpn_del_peer_nl_policy[OVPN_A_PEER + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+ [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy),
+};
+
+/* OVPN_CMD_SET_KEY - do */
+static const struct nla_policy ovpn_set_key_nl_policy[OVPN_A_PEER + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+ [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy),
+};
+
+/* OVPN_CMD_SWAP_KEYS - do */
+static const struct nla_policy ovpn_swap_keys_nl_policy[OVPN_A_PEER + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+ [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy),
+};
+
+/* OVPN_CMD_DEL_KEY - do */
+static const struct nla_policy ovpn_del_key_nl_policy[OVPN_A_PEER + 1] = {
+ [OVPN_A_IFINDEX] = { .type = NLA_U32, },
+ [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy),
+};
+
+/* Ops table for ovpn */
+static const struct genl_split_ops ovpn_nl_ops[] = {
+ {
+ .cmd = OVPN_CMD_NEW_IFACE,
+ .doit = ovpn_nl_new_iface_doit,
+ .policy = ovpn_new_iface_nl_policy,
+ .maxattr = OVPN_A_MODE,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_DEL_IFACE,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_del_iface_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_del_iface_nl_policy,
+ .maxattr = OVPN_A_IFINDEX,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_SET_PEER,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_set_peer_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_set_peer_nl_policy,
+ .maxattr = OVPN_A_PEER,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_GET_PEER,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_get_peer_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_get_peer_do_nl_policy,
+ .maxattr = OVPN_A_PEER,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_GET_PEER,
+ .dumpit = ovpn_nl_get_peer_dumpit,
+ .policy = ovpn_get_peer_dump_nl_policy,
+ .maxattr = OVPN_A_IFINDEX,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DUMP,
+ },
+ {
+ .cmd = OVPN_CMD_DEL_PEER,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_del_peer_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_del_peer_nl_policy,
+ .maxattr = OVPN_A_PEER,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_SET_KEY,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_set_key_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_set_key_nl_policy,
+ .maxattr = OVPN_A_PEER,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_SWAP_KEYS,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_swap_keys_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_swap_keys_nl_policy,
+ .maxattr = OVPN_A_PEER,
+ .flags = GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+ },
+ {
+ .cmd = OVPN_CMD_DEL_KEY,
+ .pre_doit = ovpn_nl_pre_doit,
+ .doit = ovpn_nl_del_key_doit,
+ .post_doit = ovpn_nl_post_doit,
+ .policy = ovpn_del_key_nl_policy,
+ .maxattr = OVPN_A_PEER,
+ .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 000000000000..ce11f74e1b56
--- /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_new_iface_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_del_iface_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_set_peer_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_get_peer_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_get_peer_dumpit(struct sk_buff *skb, struct netlink_callback *cb);
+int ovpn_nl_del_peer_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_set_key_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_swap_keys_doit(struct sk_buff *skb, struct genl_info *info);
+int ovpn_nl_del_key_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 000000000000..b5b53c06d64a
--- /dev/null
+++ b/drivers/net/ovpn/netlink.c
@@ -0,0 +1,153 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/netdevice.h>
+#include <net/genetlink.h>
+
+#include <uapi/linux/ovpn.h>
+
+#include "ovpnstruct.h"
+#include "main.h"
+#include "io.h"
+#include "netlink.h"
+#include "netlink-gen.h"
+
+MODULE_ALIAS_GENL_FAMILY(OVPN_FAMILY_NAME);
+
+/**
+ * ovpn_get_dev_from_attrs - retrieve the netdevice a netlink message is
+ * targeting
+ * @net: network namespace where to look for the interface
+ * @info: generic netlink info from the user request
+ *
+ * Return: the netdevice, if found, or an error otherwise
+ */
+static struct net_device *
+ovpn_get_dev_from_attrs(struct net *net, const struct genl_info *info)
+{
+ 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]);
+
+ dev = dev_get_by_index(net, ifindex);
+ if (!dev) {
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "ifindex does not match any interface");
+ return ERR_PTR(-ENODEV);
+ }
+
+ if (!ovpn_dev_is_valid(dev))
+ goto err_put_dev;
+
+ return dev;
+
+err_put_dev:
+ netdev_put(dev, NULL);
+
+ 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);
+}
+
+int ovpn_nl_pre_doit(const struct genl_split_ops *ops, struct sk_buff *skb,
+ struct genl_info *info)
+{
+ struct net *net = genl_info_net(info);
+ struct net_device *dev = ovpn_get_dev_from_attrs(net, info);
+
+ if (IS_ERR(dev))
+ return PTR_ERR(dev);
+
+ info->user_ptr[0] = netdev_priv(dev);
+
+ return 0;
+}
+
+void ovpn_nl_post_doit(const struct genl_split_ops *ops, struct sk_buff *skb,
+ struct genl_info *info)
+{
+ struct ovpn_struct *ovpn = info->user_ptr[0];
+
+ if (ovpn)
+ netdev_put(ovpn->dev, NULL);
+}
+
+int ovpn_nl_new_iface_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_del_iface_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_set_peer_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_get_peer_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_get_peer_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_del_peer_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_set_key_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_swap_keys_doit(struct sk_buff *skb, struct genl_info *info)
+{
+ return -EOPNOTSUPP;
+}
+
+int ovpn_nl_del_key_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 000000000000..9e87cf11d1e9
--- /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) 2020-2024 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/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h
new file mode 100644
index 000000000000..ff248cad1401
--- /dev/null
+++ b/drivers/net/ovpn/ovpnstruct.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2024 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_struct - per ovpn interface state
+ * @dev: the actual netdev representing the tunnel
+ */
+struct ovpn_struct {
+ 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 000000000000..677a8105b61b
--- /dev/null
+++ b/include/uapi/linux/ovpn.h
@@ -0,0 +1,108 @@
+/* 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_mode {
+ OVPN_MODE_P2P,
+ OVPN_MODE_MP,
+};
+
+enum {
+ OVPN_A_PEER_ID = 1,
+ OVPN_A_PEER_SOCKADDR_REMOTE,
+ OVPN_A_PEER_SOCKET,
+ OVPN_A_PEER_VPN_IPV4,
+ OVPN_A_PEER_VPN_IPV6,
+ OVPN_A_PEER_LOCAL_IP,
+ OVPN_A_PEER_LOCAL_PORT,
+ OVPN_A_PEER_KEEPALIVE_INTERVAL,
+ OVPN_A_PEER_KEEPALIVE_TIMEOUT,
+ OVPN_A_PEER_DEL_REASON,
+ OVPN_A_PEER_KEYCONF,
+ 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_SLOT = 1,
+ 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_MODE,
+ OVPN_A_PEER,
+
+ __OVPN_A_MAX,
+ OVPN_A_MAX = (__OVPN_A_MAX - 1)
+};
+
+enum {
+ OVPN_CMD_NEW_IFACE = 1,
+ OVPN_CMD_DEL_IFACE,
+ OVPN_CMD_SET_PEER,
+ OVPN_CMD_GET_PEER,
+ OVPN_CMD_DEL_PEER,
+ OVPN_CMD_SET_KEY,
+ OVPN_CMD_SWAP_KEYS,
+ OVPN_CMD_DEL_KEY,
+
+ __OVPN_CMD_MAX,
+ OVPN_CMD_MAX = (__OVPN_CMD_MAX - 1)
+};
+
+#define OVPN_MCGRP_PEERS "peers"
+
+#endif /* _UAPI_LINUX_OVPN_H */
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 04/25] ovpn: add basic netlink support
2024-08-27 12:07 ` [PATCH net-next v6 04/25] ovpn: add basic netlink support Antonio Quartulli
@ 2024-09-06 19:26 ` Simon Horman
2024-09-09 8:35 ` Antonio Quartulli
0 siblings, 1 reply; 58+ messages in thread
From: Simon Horman @ 2024-09-06 19:26 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
donald.hunter
On Tue, Aug 27, 2024 at 02:07:44PM +0200, Antonio Quartulli wrote:
> 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
>
> Cc: donald.hunter@gmail.com
> Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
...
> diff --git a/Documentation/netlink/specs/ovpn.yaml b/Documentation/netlink/specs/ovpn.yaml
...
> + -
> + name: keyconf
> + attributes:
> + -
> + name: slot
> + type: u32
> + doc: The slot where the key should be stored
> + enum: key-slot
> + -
> + name: key-id
> + doc: |
> + The unique ID for the key. Used to fetch the correct key upon
> + decryption
> + type: u32
> + checks:
> + max: 7
Hi Antonio,
Here max for keyconf key-id is 7.
...
> diff --git a/drivers/net/ovpn/netlink-gen.c b/drivers/net/ovpn/netlink-gen.c
...
> +/* Common nested types */
> +const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_DIR + 1] = {
> + [OVPN_A_KEYCONF_SLOT] = NLA_POLICY_MAX(NLA_U32, 1),
> + [OVPN_A_KEYCONF_KEY_ID] = NLA_POLICY_MAX(NLA_U32, 2),
But here it is 2.
Probably the patch should be refreshed after running:
tools/net/ynl/ynl-regen.sh -f
> + [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),
> +};
...
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 04/25] ovpn: add basic netlink support
2024-09-06 19:26 ` Simon Horman
@ 2024-09-09 8:35 ` Antonio Quartulli
0 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-09 8:35 UTC (permalink / raw)
To: Simon Horman
Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
donald.hunter
Hi,
On 06/09/2024 21:26, Simon Horman wrote:
>
>> diff --git a/Documentation/netlink/specs/ovpn.yaml b/Documentation/netlink/specs/ovpn.yaml
>
> ...
>
>> + -
>> + name: keyconf
>> + attributes:
>> + -
>> + name: slot
>> + type: u32
>> + doc: The slot where the key should be stored
>> + enum: key-slot
>> + -
>> + name: key-id
>> + doc: |
>> + The unique ID for the key. Used to fetch the correct key upon
>> + decryption
>> + type: u32
>> + checks:
>> + max: 7
>
> Hi Antonio,
>
> Here max for keyconf key-id is 7.
>
> ...
>
>> diff --git a/drivers/net/ovpn/netlink-gen.c b/drivers/net/ovpn/netlink-gen.c
>
> ...
>
>> +/* Common nested types */
>> +const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_DIR + 1] = {
>> + [OVPN_A_KEYCONF_SLOT] = NLA_POLICY_MAX(NLA_U32, 1),
>> + [OVPN_A_KEYCONF_KEY_ID] = NLA_POLICY_MAX(NLA_U32, 2),
>
> But here it is 2.
>
> Probably the patch should be refreshed after running:
> tools/net/ynl/ynl-regen.sh -f
You are correct.
Thanks for pointing this out.
Will get it fixed.
Cheers,
>
>> + [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),
>> +};
>
> ...
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread
* [PATCH net-next v6 05/25] ovpn: add basic interface creation/destruction/management routines
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (3 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 04/25] ovpn: add basic netlink support Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 06/25] ovpn: implement interface creation/destruction via netlink Antonio Quartulli
` (19 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
Add basic infrastructure for handling ovpn interfaces.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/main.c | 162 +++++++++++++++++++++++++++++++++-
drivers/net/ovpn/main.h | 10 +++
drivers/net/ovpn/ovpnstruct.h | 8 ++
drivers/net/ovpn/packet.h | 40 +++++++++
4 files changed, 217 insertions(+), 3 deletions(-)
create mode 100644 drivers/net/ovpn/packet.h
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index 7c35697cb596..f22259d76a0c 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -10,19 +10,62 @@
#include <linux/genetlink.h>
#include <linux/module.h>
#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
#include <linux/version.h>
+#include <net/ip.h>
#include <net/rtnetlink.h>
+#include <uapi/linux/if_arp.h>
#include <uapi/linux/ovpn.h>
#include "ovpnstruct.h"
#include "main.h"
#include "netlink.h"
#include "io.h"
+#include "packet.h"
/* Driver info */
#define DRV_DESCRIPTION "OpenVPN data channel offload (ovpn)"
#define DRV_COPYRIGHT "(C) 2020-2024 OpenVPN, Inc."
+/**
+ * ovpn_struct_init - Initialize the netdevice private area
+ * @dev: the device to initialize
+ * @mode: device operation mode (i.e. p2p, mp, ..)
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+static int ovpn_struct_init(struct net_device *dev, enum ovpn_mode mode)
+{
+ struct ovpn_struct *ovpn = netdev_priv(dev);
+
+ ovpn->dev = dev;
+ ovpn->mode = mode;
+
+ return 0;
+}
+
+static void ovpn_struct_free(struct net_device *net)
+{
+}
+
+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,
+};
+
/**
* ovpn_dev_is_valid - check if the netdevice is of type 'ovpn'
* @dev: the interface to check
@@ -41,30 +84,143 @@ static struct rtnl_link_ops ovpn_link_ops = {
.kind = OVPN_FAMILY_NAME,
};
+static void ovpn_setup(struct net_device *dev)
+{
+ /* compute the overhead considering AEAD encryption */
+ const int overhead = sizeof(u32) + NONCE_WIRE_SIZE + 16 +
+ sizeof(struct udphdr) +
+ max(sizeof(struct ipv6hdr), sizeof(struct iphdr));
+
+ 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->rtnl_link_ops = &ovpn_link_ops;
+
+ dev->priv_destructor = ovpn_struct_free;
+
+ dev->hard_header_len = 0;
+ dev->addr_len = 0;
+ dev->mtu = ETH_DATA_LEN - overhead;
+ dev->min_mtu = IPV4_MIN_MTU;
+ dev->max_mtu = IP_MAX_MTU - overhead;
+
+ dev->type = ARPHRD_NONE;
+ dev->flags = IFF_POINTOPOINT | IFF_NOARP;
+
+ dev->features |= NETIF_F_LLTX;
+ dev->features |= feat;
+ dev->hw_features |= feat;
+ dev->hw_enc_features |= feat;
+
+ dev->needed_headroom = OVPN_HEAD_ROOM;
+ dev->needed_tailroom = OVPN_MAX_PADDING;
+}
+
+/**
+ * ovpn_iface_create - create and initialize a new 'ovpn' netdevice
+ * @name: the name of the new device
+ * @mode: the OpenVPN mode to set this device to
+ * @net: the netns this device should be created in
+ *
+ * A new netdevice is created and registered.
+ * Its private area is initialized with an empty ovpn_struct object.
+ *
+ * Return: a pointer to the new device on success or a negative error code
+ * otherwise
+ */
+struct net_device *ovpn_iface_create(const char *name, enum ovpn_mode mode,
+ struct net *net)
+{
+ struct net_device *dev;
+ int ret;
+
+ dev = alloc_netdev(sizeof(struct ovpn_struct), name, NET_NAME_USER,
+ ovpn_setup);
+ if (!dev)
+ return ERR_PTR(-ENOMEM);
+
+ dev_net_set(dev, net);
+
+ ret = ovpn_struct_init(dev, mode);
+ if (ret < 0)
+ goto err;
+
+ rtnl_lock();
+ ret = register_netdevice(dev);
+ if (ret < 0) {
+ netdev_err(dev, "cannot register interface: %d\n", ret);
+ rtnl_unlock();
+ goto err;
+ }
+ /* turn carrier explicitly off after registration, this way state is
+ * clearly defined
+ */
+ netif_carrier_off(dev);
+ rtnl_unlock();
+
+ return dev;
+
+err:
+ free_netdev(dev);
+ return ERR_PTR(ret);
+}
+
+/**
+ * ovpn_iface_destruct - tear down netdevice
+ * @ovpn: the ovpn instance objected related to the interface to tear down
+ *
+ * This function takes care of tearing down an ovpn device and can be invoked
+ * internally or upon UNREGISTER netdev event
+ */
+void ovpn_iface_destruct(struct ovpn_struct *ovpn)
+{
+ ASSERT_RTNL();
+
+ netif_carrier_off(ovpn->dev);
+
+ ovpn->registered = false;
+}
+
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_struct *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;
+
+ ovpn_iface_destruct(ovpn);
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/main.h b/drivers/net/ovpn/main.h
index a3215316c49b..4dfcba9deb59 100644
--- a/drivers/net/ovpn/main.h
+++ b/drivers/net/ovpn/main.h
@@ -10,6 +10,16 @@
#ifndef _NET_OVPN_MAIN_H_
#define _NET_OVPN_MAIN_H_
+struct net_device *ovpn_iface_create(const char *name, enum ovpn_mode mode,
+ struct net *net);
+void ovpn_iface_destruct(struct ovpn_struct *ovpn);
bool ovpn_dev_is_valid(const struct net_device *dev);
+#define SKB_HEADER_LEN \
+ (max(sizeof(struct iphdr), sizeof(struct ipv6hdr)) + \
+ sizeof(struct udphdr) + NET_SKB_PAD)
+
+#define OVPN_HEAD_ROOM ALIGN(16 + SKB_HEADER_LEN, 4)
+#define OVPN_MAX_PADDING 16
+
#endif /* _NET_OVPN_MAIN_H_ */
diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h
index ff248cad1401..ee05b8a2c61d 100644
--- a/drivers/net/ovpn/ovpnstruct.h
+++ b/drivers/net/ovpn/ovpnstruct.h
@@ -10,12 +10,20 @@
#ifndef _NET_OVPN_OVPNSTRUCT_H_
#define _NET_OVPN_OVPNSTRUCT_H_
+#include <uapi/linux/ovpn.h>
+
/**
* struct ovpn_struct - 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, ..)
+ * @dev_list: entry for the module wide device list
*/
struct ovpn_struct {
struct net_device *dev;
+ bool registered;
+ enum ovpn_mode mode;
+ struct list_head dev_list;
};
#endif /* _NET_OVPN_OVPNSTRUCT_H_ */
diff --git a/drivers/net/ovpn/packet.h b/drivers/net/ovpn/packet.h
new file mode 100644
index 000000000000..7ed146f5932a
--- /dev/null
+++ b/drivers/net/ovpn/packet.h
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ * James Yonan <james@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_PACKET_H_
+#define _NET_OVPN_PACKET_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 ] -> NONCE_SIZE
+ * [4-bytes -> NONCE_WIRE_SIZE
+ * on wire]
+ */
+
+/* OpenVPN nonce size */
+#define NONCE_SIZE 12
+
+/* 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 NONCE_WIRE_SIZE (NONCE_SIZE - sizeof(struct ovpn_nonce_tail))
+
+/* Last 8 bytes of AEAD nonce
+ * Provided by userspace and usually derived from
+ * key material generated during TLS handshake
+ */
+struct ovpn_nonce_tail {
+ u8 u8[OVPN_NONCE_TAIL_SIZE];
+};
+
+#endif /* _NET_OVPN_PACKET_H_ */
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 06/25] ovpn: implement interface creation/destruction via netlink
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (4 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 05/25] ovpn: add basic interface creation/destruction/management routines Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 07/25] ovpn: keep carrier always on Antonio Quartulli
` (18 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
Allow userspace to create and destroy an interface using netlink
commands.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/main.h | 2 ++
drivers/net/ovpn/netlink.c | 59 ++++++++++++++++++++++++++++++++++++--
2 files changed, 59 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ovpn/main.h b/drivers/net/ovpn/main.h
index 4dfcba9deb59..c664d9c65573 100644
--- a/drivers/net/ovpn/main.h
+++ b/drivers/net/ovpn/main.h
@@ -10,6 +10,8 @@
#ifndef _NET_OVPN_MAIN_H_
#define _NET_OVPN_MAIN_H_
+#define OVPN_DEFAULT_IFNAME "ovpn%d"
+
struct net_device *ovpn_iface_create(const char *name, enum ovpn_mode mode,
struct net *net);
void ovpn_iface_destruct(struct ovpn_struct *ovpn);
diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c
index b5b53c06d64a..daa2f1ec46dc 100644
--- a/drivers/net/ovpn/netlink.c
+++ b/drivers/net/ovpn/netlink.c
@@ -7,6 +7,7 @@
*/
#include <linux/netdevice.h>
+#include <linux/rtnetlink.h>
#include <net/genetlink.h>
#include <uapi/linux/ovpn.h>
@@ -84,12 +85,66 @@ void ovpn_nl_post_doit(const struct genl_split_ops *ops, struct sk_buff *skb,
int ovpn_nl_new_iface_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ const char *ifname = OVPN_DEFAULT_IFNAME;
+ enum ovpn_mode mode = OVPN_MODE_P2P;
+ struct net_device *dev;
+ struct sk_buff *msg;
+ void *hdr;
+
+ if (info->attrs[OVPN_A_IFNAME])
+ ifname = nla_data(info->attrs[OVPN_A_IFNAME]);
+
+ if (info->attrs[OVPN_A_MODE]) {
+ mode = nla_get_u32(info->attrs[OVPN_A_MODE]);
+ pr_debug("ovpn: setting device (%s) mode: %u\n", ifname, mode);
+ }
+
+ dev = ovpn_iface_create(ifname, mode, genl_info_net(info));
+ if (IS_ERR(dev)) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "error while creating interface: %ld",
+ PTR_ERR(dev));
+ return PTR_ERR(dev);
+ }
+
+ msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ hdr = genlmsg_iput(msg, info);
+ if (!hdr) {
+ nlmsg_free(msg);
+ return -ENOBUFS;
+ }
+
+ if (nla_put_string(msg, OVPN_A_IFNAME, dev->name)) {
+ genlmsg_cancel(msg, hdr);
+ nlmsg_free(msg);
+ return -EMSGSIZE;
+ }
+
+ if (nla_put_u32(msg, OVPN_A_IFINDEX, dev->ifindex)) {
+ genlmsg_cancel(msg, hdr);
+ nlmsg_free(msg);
+ return -EMSGSIZE;
+ }
+
+ genlmsg_end(msg, hdr);
+
+ return genlmsg_reply(msg, info);
}
int ovpn_nl_del_iface_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct ovpn_struct *ovpn = info->user_ptr[0];
+
+ rtnl_lock();
+ ovpn_iface_destruct(ovpn);
+ unregister_netdevice(ovpn->dev);
+ netdev_put(ovpn->dev, NULL);
+ rtnl_unlock();
+
+ return 0;
}
int ovpn_nl_set_peer_doit(struct sk_buff *skb, struct genl_info *info)
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 07/25] ovpn: keep carrier always on
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (5 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 06/25] ovpn: implement interface creation/destruction via netlink Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 08/25] ovpn: introduce the ovpn_peer object Antonio Quartulli
` (17 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
An ovpn interface will keep carrier always on and let the user
decide when an interface should be considered disconnected.
This way, even if an ovpn interface is not connected to any peer,
it can still retain all IPs and routes and thus prevent any data
leak.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
---
drivers/net/ovpn/main.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index f22259d76a0c..bcc90307c108 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -50,6 +50,13 @@ static void ovpn_struct_free(struct net_device *net)
static int ovpn_net_open(struct net_device *dev)
{
+ /* ovpn keeps the carrier always on to avoid losing IP or route
+ * configuration upon disconnection. This way it can prevent leaks
+ * of traffic outside of the VPN tunnel.
+ * The user may override this behaviour by tearing down the interface
+ * manually.
+ */
+ netif_carrier_on(dev);
netif_tx_start_all_queues(dev);
return 0;
}
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 08/25] ovpn: introduce the ovpn_peer object
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (6 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 07/25] ovpn: keep carrier always on Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 09/25] ovpn: introduce the ovpn_socket object Antonio Quartulli
` (16 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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/ovpn/Makefile | 2 +
drivers/net/ovpn/bind.c | 58 ++++++
drivers/net/ovpn/bind.h | 117 +++++++++++
drivers/net/ovpn/main.c | 12 ++
drivers/net/ovpn/main.h | 2 +
drivers/net/ovpn/ovpnstruct.h | 7 +
drivers/net/ovpn/peer.c | 355 ++++++++++++++++++++++++++++++++++
drivers/net/ovpn/peer.h | 82 ++++++++
8 files changed, 635 insertions(+)
create mode 100644 drivers/net/ovpn/bind.c
create mode 100644 drivers/net/ovpn/bind.h
create mode 100644 drivers/net/ovpn/peer.c
create mode 100644 drivers/net/ovpn/peer.h
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
index 201dc001419f..ce13499b3e17 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 000000000000..b4d2ccec2ced
--- /dev/null
+++ b/drivers/net/ovpn/bind.c
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2012-2024 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/netdevice.h>
+#include <linux/socket.h>
+
+#include "ovpnstruct.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 000000000000..859213d5040d
--- /dev/null
+++ b/drivers/net/ovpn/bind.h
@@ -0,0 +1,117 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2012-2024 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;
+};
+
+/**
+ * skb_protocol_to_family - translate skb->protocol to AF_INET or AF_INET6
+ * @skb: the packet sk_buff to inspect
+ *
+ * Return: AF_INET, AF_INET6 or 0 in case of unknown protocol
+ */
+static inline unsigned short skb_protocol_to_family(const struct sk_buff *skb)
+{
+ switch (skb->protocol) {
+ case htons(ETH_P_IP):
+ return AF_INET;
+ case htons(ETH_P_IPV6):
+ return AF_INET6;
+ default:
+ return 0;
+ }
+}
+
+/**
+ * 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 unsigned short family = skb_protocol_to_family(skb);
+ const union ovpn_sockaddr *remote;
+
+ if (unlikely(!bind))
+ return false;
+
+ remote = &bind->remote;
+
+ if (unlikely(remote->in4.sin_family != family))
+ return false;
+
+ switch (family) {
+ case AF_INET:
+ 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 AF_INET6:
+ 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 bcc90307c108..7cc55d34844f 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 <linux/rcupdate.h>
#include <linux/version.h>
#include <net/ip.h>
#include <net/rtnetlink.h>
@@ -22,6 +23,7 @@
#include "netlink.h"
#include "io.h"
#include "packet.h"
+#include "peer.h"
/* Driver info */
#define DRV_DESCRIPTION "OpenVPN data channel offload (ovpn)"
@@ -40,6 +42,7 @@ static int ovpn_struct_init(struct net_device *dev, enum ovpn_mode mode)
ovpn->dev = dev;
ovpn->mode = mode;
+ spin_lock_init(&ovpn->lock);
return 0;
}
@@ -48,6 +51,11 @@ static void ovpn_struct_free(struct net_device *net)
{
}
+static int ovpn_net_init(struct net_device *dev)
+{
+ return 0;
+}
+
static int ovpn_net_open(struct net_device *dev)
{
/* ovpn keeps the carrier always on to avoid losing IP or route
@@ -68,6 +76,7 @@ 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,
@@ -192,6 +201,9 @@ void ovpn_iface_destruct(struct ovpn_struct *ovpn)
netif_carrier_off(ovpn->dev);
ovpn->registered = false;
+
+ if (ovpn->mode == OVPN_MODE_P2P)
+ ovpn_peer_release_p2p(ovpn);
}
static int ovpn_netdev_notifier_call(struct notifier_block *nb,
diff --git a/drivers/net/ovpn/main.h b/drivers/net/ovpn/main.h
index c664d9c65573..7e957248af6a 100644
--- a/drivers/net/ovpn/main.h
+++ b/drivers/net/ovpn/main.h
@@ -24,4 +24,6 @@ bool ovpn_dev_is_valid(const struct net_device *dev);
#define OVPN_HEAD_ROOM ALIGN(16 + SKB_HEADER_LEN, 4)
#define OVPN_MAX_PADDING 16
+#define OVPN_QUEUE_LEN 1024
+
#endif /* _NET_OVPN_MAIN_H_ */
diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h
index ee05b8a2c61d..25f4837b798b 100644
--- a/drivers/net/ovpn/ovpnstruct.h
+++ b/drivers/net/ovpn/ovpnstruct.h
@@ -10,19 +10,26 @@
#ifndef _NET_OVPN_OVPNSTRUCT_H_
#define _NET_OVPN_OVPNSTRUCT_H_
+#include <net/net_trackers.h>
#include <uapi/linux/ovpn.h>
/**
* struct ovpn_struct - per ovpn interface state
* @dev: the actual netdev representing the tunnel
+ * @dev_tracker: reference tracker for associated dev
* @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
* @dev_list: entry for the module wide device list
*/
struct ovpn_struct {
struct net_device *dev;
+ netdevice_tracker dev_tracker;
bool registered;
enum ovpn_mode mode;
+ spinlock_t lock; /* protect writing to the ovpn_struct object */
+ struct ovpn_peer __rcu *peer;
struct list_head dev_list;
};
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
new file mode 100644
index 000000000000..23ded79eb774
--- /dev/null
+++ b/drivers/net/ovpn/peer.c
@@ -0,0 +1,355 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/skbuff.h>
+#include <linux/list.h>
+#include <linux/workqueue.h>
+
+#include "ovpnstruct.h"
+#include "bind.h"
+#include "io.h"
+#include "main.h"
+#include "netlink.h"
+#include "peer.h"
+
+/**
+ * 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_struct *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->halt = false;
+ 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, "%s: cannot initialize dst cache\n",
+ __func__);
+ kfree(peer);
+ return ERR_PTR(ret);
+ }
+
+ netdev_hold(ovpn->dev, &ovpn->dev_tracker, GFP_KERNEL);
+
+ return 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);
+
+ dst_cache_destroy(&peer->dst_cache);
+}
+
+/**
+ * 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);
+ netdev_put(peer->ovpn->dev, &peer->ovpn->dev_tracker);
+ kfree_rcu(peer, rcu);
+}
+
+/**
+ * ovpn_peer_skb_to_sockaddr - fill sockaddr with skb source address
+ * @skb: the packet to extract data from
+ * @ss: the sockaddr to fill
+ *
+ * Return: true on success or false otherwise
+ */
+static bool ovpn_peer_skb_to_sockaddr(struct sk_buff *skb,
+ struct sockaddr_storage *ss)
+{
+ struct sockaddr_in6 *sa6;
+ struct sockaddr_in *sa4;
+
+ ss->ss_family = skb_protocol_to_family(skb);
+ switch (ss->ss_family) {
+ case AF_INET:
+ 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;
+ break;
+ case AF_INET6:
+ sa6 = (struct sockaddr_in6 *)ss;
+ sa6->sin6_family = AF_INET6;
+ sa6->sin6_addr = ipv6_hdr(skb)->saddr;
+ sa6->sin6_port = udp_hdr(skb)->source;
+ break;
+ default:
+ return false;
+ }
+
+ return true;
+}
+
+/**
+ * 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_struct *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_struct *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_struct *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_struct *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;
+}
+
+/**
+ * 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_struct *ovpn, struct ovpn_peer *peer)
+{
+ 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) {
+ tmp->delete_reason = OVPN_DEL_PEER_REASON_TEARDOWN;
+ ovpn_peer_put(tmp);
+ }
+
+ rcu_assign_pointer(ovpn->peer, peer);
+ spin_unlock_bh(&ovpn->lock);
+
+ 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_struct *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)
+ *
+ * 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)
+ __must_hold(&peer->ovpn->lock)
+{
+ struct ovpn_peer *tmp;
+
+ tmp = rcu_dereference_protected(peer->ovpn->peer,
+ lockdep_is_held(&peer->ovpn->lock));
+ if (tmp != peer) {
+ DEBUG_NET_WARN_ON_ONCE(1);
+ if (tmp)
+ ovpn_peer_put(tmp);
+
+ return -ENOENT;
+ }
+
+ tmp->delete_reason = reason;
+ RCU_INIT_POINTER(peer->ovpn->peer, NULL);
+ ovpn_peer_put(tmp);
+
+ return 0;
+}
+
+/**
+ * ovpn_peer_release_p2p - release peer upon P2P device teardown
+ * @ovpn: the instance being torn down
+ */
+void ovpn_peer_release_p2p(struct ovpn_struct *ovpn)
+{
+ struct ovpn_peer *tmp;
+
+ spin_lock_bh(&ovpn->lock);
+ tmp = rcu_dereference_protected(ovpn->peer,
+ lockdep_is_held(&ovpn->lock));
+ if (tmp)
+ ovpn_peer_del_p2p(tmp, OVPN_DEL_PEER_REASON_TEARDOWN);
+ spin_unlock_bh(&ovpn->lock);
+}
+
+/**
+ * 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)
+{
+ switch (peer->ovpn->mode) {
+ case OVPN_MODE_P2P:
+ return ovpn_peer_del_p2p(peer, reason);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
new file mode 100644
index 000000000000..6c51959363c7
--- /dev/null
+++ b/drivers/net/ovpn/peer.h
@@ -0,0 +1,82 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_OVPNPEER_H_
+#define _NET_OVPN_OVPNPEER_H_
+
+#include "bind.h"
+
+#include <net/dst_cache.h>
+#include <uapi/linux/ovpn.h>
+
+/**
+ * struct ovpn_peer - the main remote peer object
+ * @ovpn: main openvpn instance this peer belongs to
+ * @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
+ * @halt: true if ovpn_peer_mark_delete was called
+ * @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
+ * @delete_work: deferred cleanup work, used to notify userspace
+ */
+struct ovpn_peer {
+ struct ovpn_struct *ovpn;
+ u32 id;
+ struct {
+ struct in_addr ipv4;
+ struct in6_addr ipv6;
+ } vpn_addrs;
+ struct dst_cache dst_cache;
+ struct ovpn_bind __rcu *bind;
+ bool halt;
+ enum ovpn_del_peer_reason delete_reason;
+ spinlock_t lock; /* protects bind */
+ struct kref refcount;
+ struct rcu_head rcu;
+ struct work_struct delete_work;
+};
+
+/**
+ * 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_struct *ovpn, u32 id);
+int ovpn_peer_add(struct ovpn_struct *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_struct *ovpn);
+
+struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_struct *ovpn,
+ struct sk_buff *skb);
+struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_struct *ovpn, u32 peer_id);
+
+#endif /* _NET_OVPN_OVPNPEER_H_ */
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 09/25] ovpn: introduce the ovpn_socket object
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (7 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 08/25] ovpn: introduce the ovpn_peer object Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 10/25] ovpn: implement basic TX path (UDP) Antonio Quartulli
` (15 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/Makefile | 2 +
drivers/net/ovpn/socket.c | 120 ++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/socket.h | 48 +++++++++++++++
drivers/net/ovpn/udp.c | 72 +++++++++++++++++++++++
drivers/net/ovpn/udp.h | 17 ++++++
5 files changed, 259 insertions(+)
create mode 100644 drivers/net/ovpn/socket.c
create mode 100644 drivers/net/ovpn/socket.h
create mode 100644 drivers/net/ovpn/udp.c
create mode 100644 drivers/net/ovpn/udp.h
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
index ce13499b3e17..56bddc9bef83 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/socket.c b/drivers/net/ovpn/socket.c
new file mode 100644
index 000000000000..090a3232ab0e
--- /dev/null
+++ b/drivers/net/ovpn/socket.c
@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/net.h>
+#include <linux/netdevice.h>
+
+#include "ovpnstruct.h"
+#include "main.h"
+#include "io.h"
+#include "peer.h"
+#include "socket.h"
+#include "udp.h"
+
+static void ovpn_socket_detach(struct socket *sock)
+{
+ if (!sock)
+ return;
+
+ sockfd_put(sock);
+}
+
+/**
+ * ovpn_socket_release_kref - kref_put callback
+ * @kref: the kref object
+ */
+void ovpn_socket_release_kref(struct kref *kref)
+{
+ struct ovpn_socket *sock = container_of(kref, struct ovpn_socket,
+ refcount);
+
+ ovpn_socket_detach(sock->sock);
+ kfree_rcu(sock, rcu);
+}
+
+static bool ovpn_socket_hold(struct ovpn_socket *sock)
+{
+ return kref_get_unless_zero(&sock->refcount);
+}
+
+static struct ovpn_socket *ovpn_socket_get(struct socket *sock)
+{
+ struct ovpn_socket *ovpn_sock;
+
+ rcu_read_lock();
+ ovpn_sock = rcu_dereference_sk_user_data(sock->sk);
+ if (!ovpn_socket_hold(ovpn_sock)) {
+ pr_warn("%s: found ovpn_socket with ref = 0\n", __func__);
+ ovpn_sock = NULL;
+ }
+ rcu_read_unlock();
+
+ return ovpn_sock;
+}
+
+static int ovpn_socket_attach(struct socket *sock, struct ovpn_peer *peer)
+{
+ int ret = -EOPNOTSUPP;
+
+ if (!sock || !peer)
+ return -EINVAL;
+
+ if (sock->sk->sk_protocol == IPPROTO_UDP)
+ ret = ovpn_udp_socket_attach(sock, peer->ovpn);
+
+ return ret;
+}
+
+/**
+ * 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;
+
+ ret = ovpn_socket_attach(sock, peer);
+ if (ret < 0 && ret != -EALREADY)
+ return ERR_PTR(ret);
+
+ /* if this socket is already owned by this interface, just increase the
+ * refcounter and use it as expected.
+ *
+ * Since UDP sockets can be used to talk to multiple remote endpoints,
+ * openvpn normally instantiates only one socket and shares it among all
+ * its peers. For this reason, when we find out that a socket is already
+ * used for some other peer in *this* instance, we can happily increase
+ * its refcounter and use it normally.
+ */
+ if (ret == -EALREADY) {
+ /* 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.
+ */
+ ovpn_sock = ovpn_socket_get(sock);
+ sockfd_put(sock);
+ return ovpn_sock;
+ }
+
+ ovpn_sock = kzalloc(sizeof(*ovpn_sock), GFP_KERNEL);
+ if (!ovpn_sock)
+ return ERR_PTR(-ENOMEM);
+
+ ovpn_sock->ovpn = peer->ovpn;
+ ovpn_sock->sock = sock;
+ kref_init(&ovpn_sock->refcount);
+
+ rcu_assign_sk_user_data(sock->sk, ovpn_sock);
+
+ return ovpn_sock;
+}
diff --git a/drivers/net/ovpn/socket.h b/drivers/net/ovpn/socket.h
new file mode 100644
index 000000000000..5ad9c5073b08
--- /dev/null
+++ b/drivers/net/ovpn/socket.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 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_struct;
+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_struct *ovpn;
+ struct socket *sock;
+ struct kref refcount;
+ struct rcu_head rcu;
+};
+
+void ovpn_socket_release_kref(struct kref *kref);
+
+/**
+ * ovpn_socket_put - decrease reference counter
+ * @sock: the socket whose reference counter should be decreased
+ */
+static inline void ovpn_socket_put(struct ovpn_socket *sock)
+{
+ kref_put(&sock->refcount, ovpn_socket_release_kref);
+}
+
+struct ovpn_socket *ovpn_socket_new(struct socket *sock,
+ 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 000000000000..c10474d252e1
--- /dev/null
+++ b/drivers/net/ovpn/udp.c
@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2024 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/netdevice.h>
+#include <linux/socket.h>
+#include <net/udp.h>
+
+#include "ovpnstruct.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
+ * @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 socket *sock, struct ovpn_struct *ovpn)
+{
+ struct ovpn_socket *old_data;
+ int ret = 0;
+
+ /* sanity check */
+ if (sock->sk->sk_protocol != IPPROTO_UDP) {
+ DEBUG_NET_WARN_ON_ONCE(1);
+ return -EINVAL;
+ }
+
+ /* 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,
+ "%s: provided socket already owned by this interface\n",
+ __func__);
+ ret = -EALREADY;
+ } else {
+ netdev_err(ovpn->dev,
+ "%s: provided socket already taken by other user\n",
+ __func__);
+ ret = -EBUSY;
+ }
+ rcu_read_unlock();
+
+ return ret;
+}
diff --git a/drivers/net/ovpn/udp.h b/drivers/net/ovpn/udp.h
new file mode 100644
index 000000000000..f2507f8f2c71
--- /dev/null
+++ b/drivers/net/ovpn/udp.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2024 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_UDP_H_
+#define _NET_OVPN_UDP_H_
+
+struct ovpn_struct;
+struct socket;
+
+int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_struct *ovpn);
+
+#endif /* _NET_OVPN_UDP_H_ */
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 10/25] ovpn: implement basic TX path (UDP)
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (8 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 09/25] ovpn: introduce the ovpn_socket object Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-08-30 17:02 ` Sabrina Dubroca
2024-08-27 12:07 ` [PATCH net-next v6 11/25] ovpn: implement basic RX " Antonio Quartulli
` (14 subsequent siblings)
24 siblings, 1 reply; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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/ovpn/io.c | 143 ++++++++++++++++++++++++-
drivers/net/ovpn/peer.c | 37 ++++++-
drivers/net/ovpn/peer.h | 5 +
drivers/net/ovpn/skb.h | 54 ++++++++++
drivers/net/ovpn/udp.c | 230 ++++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/udp.h | 8 ++
6 files changed, 474 insertions(+), 3 deletions(-)
create mode 100644 drivers/net/ovpn/skb.h
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index ad3813419c33..cbb42086f1fc 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -9,14 +9,155 @@
#include <linux/netdevice.h>
#include <linux/skbuff.h>
+#include <net/gso.h>
#include "io.h"
+#include "ovpnstruct.h"
+#include "peer.h"
+#include "udp.h"
+#include "skb.h"
+
+static void ovpn_encrypt_post(struct sk_buff *skb, int ret)
+{
+ struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;
+
+ if (unlikely(ret < 0))
+ goto err;
+
+ skb_mark_not_on_list(skb);
+
+ switch (peer->sock->sock->sk->sk_protocol) {
+ case IPPROTO_UDP:
+ ovpn_udp_send_skb(peer->ovpn, peer, skb);
+ break;
+ default:
+ /* no transport configured yet */
+ goto err;
+ }
+ /* skb passed down the stack - don't free it */
+ skb = NULL;
+err:
+ if (unlikely(skb)) {
+ dev_core_stats_tx_dropped_inc(peer->ovpn->dev);
+ kfree_skb(skb);
+ }
+ ovpn_peer_put(peer);
+}
+
+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_struct *ovpn, struct sk_buff *skb,
+ struct ovpn_peer *peer)
+{
+ struct sk_buff *curr, *next;
+
+ if (likely(!peer))
+ /* 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",
+ ovpn->dev->name);
+ dev_core_stats_tx_dropped_inc(ovpn->dev);
+ goto drop;
+ }
+
+ /* 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);
+ }
+
+ /* skb passed over, no need to free */
+ skb = NULL;
+drop:
+ if (likely(peer))
+ ovpn_peer_put(peer);
+ kfree_skb_list(skb);
+}
/* Send user data to the network
*/
netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev)
{
+ struct ovpn_struct *ovpn = netdev_priv(dev);
+ struct sk_buff *segments, *tmp, *curr, *next;
+ struct sk_buff_head skb_list;
+ __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)) {
+ net_err_ratelimited("%s: dropping malformed payload packet\n",
+ dev->name);
+ dev_core_stats_tx_dropped_inc(ovpn->dev);
+ 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 packet: %d\n",
+ dev->name, ret);
+ dev_core_stats_tx_dropped_inc(ovpn->dev);
+ 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);
+
+ tmp = skb_share_check(curr, GFP_ATOMIC);
+ if (unlikely(!tmp)) {
+ kfree_skb_list(next);
+ net_err_ratelimited("%s: skb_share_check failed\n",
+ dev->name);
+ goto drop_list;
+ }
+
+ __skb_queue_tail(&skb_list, tmp);
+ }
+ skb_list.prev->next = NULL;
+
+ ovpn_send(ovpn, skb_list.next, NULL);
+
+ return NETDEV_TX_OK;
+
+drop_list:
+ skb_queue_walk_safe(&skb_list, curr, next) {
+ dev_core_stats_tx_dropped_inc(ovpn->dev);
+ kfree_skb(curr);
+ }
+drop:
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 23ded79eb774..6bde4bd9395b 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -9,7 +9,6 @@
#include <linux/skbuff.h>
#include <linux/list.h>
-#include <linux/workqueue.h>
#include "ovpnstruct.h"
#include "bind.h"
@@ -65,8 +64,10 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_struct *ovpn, u32 id)
*/
static void ovpn_peer_release(struct ovpn_peer *peer)
{
- ovpn_bind_reset(peer, NULL);
+ if (peer->sock)
+ ovpn_socket_put(peer->sock);
+ ovpn_bind_reset(peer, NULL);
dst_cache_destroy(&peer->dst_cache);
}
@@ -244,6 +245,38 @@ struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_struct *ovpn, u32 peer_id)
return peer;
}
+/**
+ * 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_struct *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 6c51959363c7..37de5aff54a8 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -11,6 +11,7 @@
#define _NET_OVPN_OVPNPEER_H_
#include "bind.h"
+#include "socket.h"
#include <net/dst_cache.h>
#include <uapi/linux/ovpn.h>
@@ -22,6 +23,7 @@
* @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
* @halt: true if ovpn_peer_mark_delete was called
@@ -38,6 +40,7 @@ struct ovpn_peer {
struct in_addr ipv4;
struct in6_addr ipv6;
} vpn_addrs;
+ struct ovpn_socket *sock;
struct dst_cache dst_cache;
struct ovpn_bind __rcu *bind;
bool halt;
@@ -78,5 +81,7 @@ void ovpn_peer_release_p2p(struct ovpn_struct *ovpn);
struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_struct *ovpn,
struct sk_buff *skb);
struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_struct *ovpn, u32 peer_id);
+struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_struct *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 000000000000..7966a10d915f
--- /dev/null
+++ b/drivers/net/ovpn/skb.h
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 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/skbuff.h>
+#include <linux/socket.h>
+#include <linux/types.h>
+
+struct ovpn_cb {
+ struct aead_request *req;
+ struct ovpn_peer *peer;
+ struct ovpn_crypto_key_slot *ks;
+ unsigned int payload_offset;
+};
+
+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)
+ proto = htons(ETH_P_IPV6);
+
+ return proto;
+}
+
+#endif /* _NET_OVPN_SKB_H_ */
diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c
index c10474d252e1..0b1a541732a2 100644
--- a/drivers/net/ovpn/udp.c
+++ b/drivers/net/ovpn/udp.c
@@ -7,14 +7,244 @@
*/
#include <linux/netdevice.h>
+#include <linux/inetdevice.h>
#include <linux/socket.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 "ovpnstruct.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
+ * @ovpn: the openvpn instance
+ * @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_struct *ovpn, 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;
+ bind->local.ipv4.s_addr = 0;
+ 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;
+ bind->local.ipv4.s_addr = 0;
+ 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",
+ ovpn->dev->name, &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
+ * @ovpn: the openvpn instance
+ * @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_struct *ovpn, 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;
+ bind->local.ipv6 = in6addr_any;
+ 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",
+ ovpn->dev->name, &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
+ * @ovpn: the openvpn instance
+ * @bind: the binding related to 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_struct *ovpn, struct ovpn_bind *bind,
+ struct dst_cache *cache, struct sock *sk,
+ struct sk_buff *skb)
+{
+ 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;
+
+ switch (bind->remote.in4.sin_family) {
+ case AF_INET:
+ ret = ovpn_udp4_output(ovpn, bind, cache, sk, skb);
+ break;
+#if IS_ENABLED(CONFIG_IPV6)
+ case AF_INET6:
+ ret = ovpn_udp6_output(ovpn, bind, cache, sk, skb);
+ break;
+#endif
+ default:
+ ret = -EAFNOSUPPORT;
+ break;
+ }
+
+ return ret;
+}
+
+/**
+ * ovpn_udp_send_skb - prepare skb and send it over via UDP
+ * @ovpn: the openvpn instance
+ * @peer: the destination peer
+ * @skb: the packet to send
+ */
+void ovpn_udp_send_skb(struct ovpn_struct *ovpn, struct ovpn_peer *peer,
+ struct sk_buff *skb)
+{
+ struct ovpn_bind *bind;
+ struct socket *sock;
+ int ret = -1;
+
+ skb->dev = ovpn->dev;
+ /* no checksum performed at this layer */
+ skb->ip_summed = CHECKSUM_NONE;
+
+ /* get socket info */
+ sock = peer->sock->sock;
+ if (unlikely(!sock)) {
+ net_warn_ratelimited("%s: no sock for remote peer\n", __func__);
+ goto out;
+ }
+
+ rcu_read_lock();
+ /* get binding */
+ bind = rcu_dereference(peer->bind);
+ if (unlikely(!bind)) {
+ net_warn_ratelimited("%s: no bind for remote peer\n", __func__);
+ goto out_unlock;
+ }
+
+ /* crypto layer -> transport (UDP) */
+ ret = ovpn_udp_output(ovpn, bind, &peer->dst_cache, sock->sk, skb);
+
+out_unlock:
+ rcu_read_unlock();
+out:
+ if (unlikely(ret < 0)) {
+ dev_core_stats_tx_dropped_inc(ovpn->dev);
+ kfree_skb(skb);
+ return;
+ }
+
+ dev_sw_netstats_tx_add(ovpn->dev, 1, skb->len);
+}
+
/**
* ovpn_udp_socket_attach - set udp-tunnel CBs on socket and link it to ovpn
* @sock: socket to configure
diff --git a/drivers/net/ovpn/udp.h b/drivers/net/ovpn/udp.h
index f2507f8f2c71..e60f8cd2b4ac 100644
--- a/drivers/net/ovpn/udp.h
+++ b/drivers/net/ovpn/udp.h
@@ -9,9 +9,17 @@
#ifndef _NET_OVPN_UDP_H_
#define _NET_OVPN_UDP_H_
+#include <linux/skbuff.h>
+#include <net/sock.h>
+
+struct ovpn_peer;
struct ovpn_struct;
+struct sk_buff;
struct socket;
int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_struct *ovpn);
+void ovpn_udp_send_skb(struct ovpn_struct *ovpn, struct ovpn_peer *peer,
+ struct sk_buff *skb);
+
#endif /* _NET_OVPN_UDP_H_ */
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 10/25] ovpn: implement basic TX path (UDP)
2024-08-27 12:07 ` [PATCH net-next v6 10/25] ovpn: implement basic TX path (UDP) Antonio Quartulli
@ 2024-08-30 17:02 ` Sabrina Dubroca
2024-09-02 12:03 ` Antonio Quartulli
0 siblings, 1 reply; 58+ messages in thread
From: Sabrina Dubroca @ 2024-08-30 17:02 UTC (permalink / raw)
To: Antonio Quartulli; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
Hi Antonio,
Thanks for the updated patchset. I'm going through it again.
2024-08-27, 14:07:50 +0200, Antonio Quartulli wrote:
> +/* send skb to connected peer, if any */
> +static void ovpn_send(struct ovpn_struct *ovpn, struct sk_buff *skb,
> + struct ovpn_peer *peer)
> +{
> + struct sk_buff *curr, *next;
> +
> + if (likely(!peer))
> + /* 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",
> + ovpn->dev->name);
> + dev_core_stats_tx_dropped_inc(ovpn->dev);
> + goto drop;
> + }
> +
> + /* 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);
Is this a bit inconsistent with ovpn_net_xmit's behavior? There we
drop the full list if we fail one skb_share_check, and here we only
drop the single packet that failed and handle the rest? Or am I
misreading this?
> + }
> +
> + /* skb passed over, no need to free */
> + skb = NULL;
> +drop:
> + if (likely(peer))
> + ovpn_peer_put(peer);
> + kfree_skb_list(skb);
> +}
>
> /* Send user data to the network
> */
> netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev)
> {
> + struct ovpn_struct *ovpn = netdev_priv(dev);
> + struct sk_buff *segments, *tmp, *curr, *next;
> + struct sk_buff_head skb_list;
> + __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)) {
> + net_err_ratelimited("%s: dropping malformed payload packet\n",
> + dev->name);
> + dev_core_stats_tx_dropped_inc(ovpn->dev);
> + 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 packet: %d\n",
> + dev->name, ret);
> + dev_core_stats_tx_dropped_inc(ovpn->dev);
> + 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);
> +
> + tmp = skb_share_check(curr, GFP_ATOMIC);
> + if (unlikely(!tmp)) {
> + kfree_skb_list(next);
Those don't get counted as dropped, but the ones we've already handled
(and put on skb_list) will be counted as dev_core_stats_tx_dropped_inc?
(it probably doesn't matter that much, since if we'd dropped before/at
skb_gso_segment we'd only count one drop)
> + net_err_ratelimited("%s: skb_share_check failed\n",
> + dev->name);
> + goto drop_list;
> + }
> +
> + __skb_queue_tail(&skb_list, tmp);
> + }
> + skb_list.prev->next = NULL;
> +
> + ovpn_send(ovpn, skb_list.next, NULL);
> +
> + return NETDEV_TX_OK;
> +
> +drop_list:
> + skb_queue_walk_safe(&skb_list, curr, next) {
> + dev_core_stats_tx_dropped_inc(ovpn->dev);
> + kfree_skb(curr);
> + }
> +drop:
> skb_tx_error(skb);
> - kfree_skb(skb);
> + kfree_skb_list(skb);
> return NET_XMIT_DROP;
> }
[...]
> +void ovpn_udp_send_skb(struct ovpn_struct *ovpn, struct ovpn_peer *peer,
> + struct sk_buff *skb)
> +{
> + struct ovpn_bind *bind;
> + struct socket *sock;
> + int ret = -1;
> +
> + skb->dev = ovpn->dev;
> + /* no checksum performed at this layer */
> + skb->ip_summed = CHECKSUM_NONE;
> +
> + /* get socket info */
> + sock = peer->sock->sock;
> + if (unlikely(!sock)) {
> + net_warn_ratelimited("%s: no sock for remote peer\n", __func__);
> + goto out;
> + }
> +
> + rcu_read_lock();
> + /* get binding */
> + bind = rcu_dereference(peer->bind);
> + if (unlikely(!bind)) {
> + net_warn_ratelimited("%s: no bind for remote peer\n", __func__);
> + goto out_unlock;
> + }
> +
> + /* crypto layer -> transport (UDP) */
> + ret = ovpn_udp_output(ovpn, bind, &peer->dst_cache, sock->sk, skb);
> +
> +out_unlock:
> + rcu_read_unlock();
> +out:
> + if (unlikely(ret < 0)) {
> + dev_core_stats_tx_dropped_inc(ovpn->dev);
> + kfree_skb(skb);
> + return;
> + }
> +
> + dev_sw_netstats_tx_add(ovpn->dev, 1, skb->len);
I don't think it's safe to access skb->len after calling
udp_tunnel(6)_xmit_skb.
For example, vxlan_xmit_one (drivers/net/vxlan/vxlan_core.c) has a
similar counter and saves skb->len into pkt_len.
--
Sabrina
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 10/25] ovpn: implement basic TX path (UDP)
2024-08-30 17:02 ` Sabrina Dubroca
@ 2024-09-02 12:03 ` Antonio Quartulli
0 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-02 12:03 UTC (permalink / raw)
To: Sabrina Dubroca; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
On 30/08/2024 19:02, Sabrina Dubroca wrote:
> Hi Antonio,
>
> Thanks for the updated patchset. I'm going through it again.
>
> 2024-08-27, 14:07:50 +0200, Antonio Quartulli wrote:
>> +/* send skb to connected peer, if any */
>> +static void ovpn_send(struct ovpn_struct *ovpn, struct sk_buff *skb,
>> + struct ovpn_peer *peer)
>> +{
>> + struct sk_buff *curr, *next;
>> +
>> + if (likely(!peer))
>> + /* 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",
>> + ovpn->dev->name);
>> + dev_core_stats_tx_dropped_inc(ovpn->dev);
>> + goto drop;
>> + }
>> +
>> + /* 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);
>
> Is this a bit inconsistent with ovpn_net_xmit's behavior? There we
> drop the full list if we fail one skb_share_check, and here we only
> drop the single packet that failed and handle the rest? Or am I
> misreading this?
You're right, it's inconsistent.
In ovpn_send() each call to ovpn_encrypt_one() will result in the skb
being sent, therefore, if we wanted, we could free only skbs we haven't
sent yet.
Maybe it makes sense to always try sending the rest and assume that the
upper layer will deal with the missing data.
I'll adjust ovpn_net_xmit() to drop only the failing skb and move on.
>
>> + }
>> +
>> + /* skb passed over, no need to free */
>> + skb = NULL;
>> +drop:
>> + if (likely(peer))
>> + ovpn_peer_put(peer);
>> + kfree_skb_list(skb);
>> +}
>>
>> /* Send user data to the network
>> */
>> netdev_tx_t ovpn_net_xmit(struct sk_buff *skb, struct net_device *dev)
>> {
>> + struct ovpn_struct *ovpn = netdev_priv(dev);
>> + struct sk_buff *segments, *tmp, *curr, *next;
>> + struct sk_buff_head skb_list;
>> + __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)) {
>> + net_err_ratelimited("%s: dropping malformed payload packet\n",
>> + dev->name);
>> + dev_core_stats_tx_dropped_inc(ovpn->dev);
>> + 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 packet: %d\n",
>> + dev->name, ret);
>> + dev_core_stats_tx_dropped_inc(ovpn->dev);
>> + 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);
>> +
>> + tmp = skb_share_check(curr, GFP_ATOMIC);
>> + if (unlikely(!tmp)) {
>> + kfree_skb_list(next);
>
> Those don't get counted as dropped, but the ones we've already handled
> (and put on skb_list) will be counted as dev_core_stats_tx_dropped_inc?
> (it probably doesn't matter that much, since if we'd dropped before/at
> skb_gso_segment we'd only count one drop)
Once I change this part, I'll ensure we count each single dropped packet.
The downside is that any failure before skb_gso_segment() is counted as
1 drop, while anything later than that is counter per-segment.
I don't think we can do anything about it though.
>
>> + net_err_ratelimited("%s: skb_share_check failed\n",
>> + dev->name);
>> + goto drop_list;
>> + }
>> +
>> + __skb_queue_tail(&skb_list, tmp);
>> + }
>> + skb_list.prev->next = NULL;
>> +
>> + ovpn_send(ovpn, skb_list.next, NULL);
>> +
>> + return NETDEV_TX_OK;
>> +
>> +drop_list:
>> + skb_queue_walk_safe(&skb_list, curr, next) {
>> + dev_core_stats_tx_dropped_inc(ovpn->dev);
>> + kfree_skb(curr);
>> + }
>> +drop:
>> skb_tx_error(skb);
>> - kfree_skb(skb);
>> + kfree_skb_list(skb);
>> return NET_XMIT_DROP;
>> }
>
>
> [...]
>> +void ovpn_udp_send_skb(struct ovpn_struct *ovpn, struct ovpn_peer *peer,
>> + struct sk_buff *skb)
>> +{
>> + struct ovpn_bind *bind;
>> + struct socket *sock;
>> + int ret = -1;
>> +
>> + skb->dev = ovpn->dev;
>> + /* no checksum performed at this layer */
>> + skb->ip_summed = CHECKSUM_NONE;
>> +
>> + /* get socket info */
>> + sock = peer->sock->sock;
>> + if (unlikely(!sock)) {
>> + net_warn_ratelimited("%s: no sock for remote peer\n", __func__);
>> + goto out;
>> + }
>> +
>> + rcu_read_lock();
>> + /* get binding */
>> + bind = rcu_dereference(peer->bind);
>> + if (unlikely(!bind)) {
>> + net_warn_ratelimited("%s: no bind for remote peer\n", __func__);
>> + goto out_unlock;
>> + }
>> +
>> + /* crypto layer -> transport (UDP) */
>> + ret = ovpn_udp_output(ovpn, bind, &peer->dst_cache, sock->sk, skb);
>> +
>> +out_unlock:
>> + rcu_read_unlock();
>> +out:
>> + if (unlikely(ret < 0)) {
>> + dev_core_stats_tx_dropped_inc(ovpn->dev);
>> + kfree_skb(skb);
>> + return;
>> + }
>> +
>> + dev_sw_netstats_tx_add(ovpn->dev, 1, skb->len);
>
> I don't think it's safe to access skb->len after calling
> udp_tunnel(6)_xmit_skb.
Absolutely right! Thanks!
>
> For example, vxlan_xmit_one (drivers/net/vxlan/vxlan_core.c) has a
> similar counter and saves skb->len into pkt_len.
Yap, will do the same.
Cheers,
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread
* [PATCH net-next v6 11/25] ovpn: implement basic RX path (UDP)
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (9 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 10/25] ovpn: implement basic TX path (UDP) Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-09-02 11:22 ` Sabrina Dubroca
2024-09-06 19:18 ` Simon Horman
2024-08-27 12:07 ` [PATCH net-next v6 12/25] ovpn: implement packet processing Antonio Quartulli
` (13 subsequent siblings)
24 siblings, 2 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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 | 63 +++++++++++++++++++-
drivers/net/ovpn/io.h | 2 +
drivers/net/ovpn/main.c | 9 ++-
drivers/net/ovpn/ovpnstruct.h | 3 +
drivers/net/ovpn/proto.h | 75 ++++++++++++++++++++++++
drivers/net/ovpn/skb.h | 3 -
drivers/net/ovpn/socket.c | 24 ++++++++
drivers/net/ovpn/udp.c | 104 +++++++++++++++++++++++++++++++++-
drivers/net/ovpn/udp.h | 3 +-
9 files changed, 279 insertions(+), 7 deletions(-)
create mode 100644 drivers/net/ovpn/proto.h
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index cbb42086f1fc..ad986c66dbdf 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -9,14 +9,75 @@
#include <linux/netdevice.h>
#include <linux/skbuff.h>
+#include <net/gro_cells.h>
#include <net/gso.h>
-#include "io.h"
#include "ovpnstruct.h"
#include "peer.h"
+#include "io.h"
+#include "netlink.h"
+#include "proto.h"
#include "udp.h"
#include "skb.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)
+{
+ /* 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_probe_transport_header(skb);
+ skb_reset_inner_headers(skb);
+
+ memset(skb->cb, 0, sizeof(skb->cb));
+
+ /* cause packet to be "received" by the interface */
+ if (likely(gro_cells_receive(&peer->ovpn->gro_cells,
+ skb) == NET_RX_SUCCESS))
+ /* update RX stats with the size of decrypted packet */
+ dev_sw_netstats_rx_add(peer->ovpn->dev, skb->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);
+ kfree_skb(skb);
+ ovpn_peer_put(peer);
+}
+
+/* pick next packet from RX queue, decrypt 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 aa259be66441..9667a0a470e0 100644
--- a/drivers/net/ovpn/io.h
+++ b/drivers/net/ovpn/io.h
@@ -12,4 +12,6 @@
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 7cc55d34844f..caa38f6bee2a 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -13,6 +13,7 @@
#include <linux/inetdevice.h>
//#include <linux/rcupdate.h>
#include <linux/version.h>
+#include <net/gro_cells.h>
#include <net/ip.h>
#include <net/rtnetlink.h>
#include <uapi/linux/if_arp.h>
@@ -49,11 +50,17 @@ static int ovpn_struct_init(struct net_device *dev, enum ovpn_mode mode)
static void ovpn_struct_free(struct net_device *net)
{
+ struct ovpn_struct *ovpn = netdev_priv(net);
+
+ gro_cells_destroy(&ovpn->gro_cells);
+ rcu_barrier();
}
static int ovpn_net_init(struct net_device *dev)
{
- return 0;
+ struct ovpn_struct *ovpn = netdev_priv(dev);
+
+ return gro_cells_init(&ovpn->gro_cells, dev);
}
static int ovpn_net_open(struct net_device *dev)
diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h
index 25f4837b798b..65497ce115aa 100644
--- a/drivers/net/ovpn/ovpnstruct.h
+++ b/drivers/net/ovpn/ovpnstruct.h
@@ -10,6 +10,7 @@
#ifndef _NET_OVPN_OVPNSTRUCT_H_
#define _NET_OVPN_OVPNSTRUCT_H_
+#include <net/gro_cells.h>
#include <net/net_trackers.h>
#include <uapi/linux/ovpn.h>
@@ -22,6 +23,7 @@
* @lock: protect this object
* @peer: in P2P mode, this is the only remote peer
* @dev_list: entry for the module wide device list
+ * @gro_cells: pointer to the Generic Receive Offload cell
*/
struct ovpn_struct {
struct net_device *dev;
@@ -31,6 +33,7 @@ struct ovpn_struct {
spinlock_t lock; /* protect writing to the ovpn_struct object */
struct ovpn_peer __rcu *peer;
struct list_head dev_list;
+ struct gro_cells gro_cells;
};
#endif /* _NET_OVPN_OVPNSTRUCT_H_ */
diff --git a/drivers/net/ovpn/proto.h b/drivers/net/ovpn/proto.h
new file mode 100644
index 000000000000..69604cf26bbf
--- /dev/null
+++ b/drivers/net/ovpn/proto.h
@@ -0,0 +1,75 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ * James Yonan <james@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_OVPNPROTO_H_
+#define _NET_OVPN_OVPNPROTO_H_
+
+#include "main.h"
+
+#include <linux/skbuff.h>
+
+/* Methods for operating on the initial command
+ * byte of the OpenVPN protocol.
+ */
+
+/* packet opcode (high 5 bits) and key-id (low 3 bits) are combined in
+ * one byte
+ */
+#define OVPN_KEY_ID_MASK 0x07
+#define OVPN_OPCODE_SHIFT 3
+#define OVPN_OPCODE_MASK 0x1F
+/* upper bounds on opcode and key ID */
+#define OVPN_KEY_ID_MAX (OVPN_KEY_ID_MASK + 1)
+#define OVPN_OPCODE_MAX (OVPN_OPCODE_MASK + 1)
+/* packet opcodes of interest to us */
+#define OVPN_DATA_V1 6 /* data channel V1 packet */
+#define OVPN_DATA_V2 9 /* data channel V2 packet */
+/* size of initial packet opcode */
+#define OVPN_OP_SIZE_V1 1
+#define OVPN_OP_SIZE_V2 4
+#define OVPN_PEER_ID_MASK 0x00FFFFFF
+#define OVPN_PEER_ID_UNDEF 0x00FFFFFF
+/* first byte of keepalive message */
+#define OVPN_KEEPALIVE_FIRST_BYTE 0x2a
+/* first byte of exit message */
+#define OVPN_EXPLICIT_EXIT_NOTIFY_FIRST_BYTE 0x28
+
+/**
+ * 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 byte.
+ *
+ * Return: the OP code
+ */
+static inline u8 ovpn_opcode_from_skb(const struct sk_buff *skb, u16 offset)
+{
+ u8 byte = *(skb->data + offset);
+
+ return byte >> OVPN_OPCODE_SHIFT;
+}
+
+/**
+ * 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)
+{
+ return ntohl(*(__be32 *)(skb->data + offset)) & OVPN_PEER_ID_MASK;
+}
+
+#endif /* _NET_OVPN_OVPNPROTO_H_ */
diff --git a/drivers/net/ovpn/skb.h b/drivers/net/ovpn/skb.h
index 7966a10d915f..e070fe6f448c 100644
--- a/drivers/net/ovpn/skb.h
+++ b/drivers/net/ovpn/skb.h
@@ -18,10 +18,7 @@
#include <linux/types.h>
struct ovpn_cb {
- struct aead_request *req;
struct ovpn_peer *peer;
- struct ovpn_crypto_key_slot *ks;
- unsigned int payload_offset;
};
static inline struct ovpn_cb *ovpn_skb_cb(struct sk_buff *skb)
diff --git a/drivers/net/ovpn/socket.c b/drivers/net/ovpn/socket.c
index 090a3232ab0e..964b566de69f 100644
--- a/drivers/net/ovpn/socket.c
+++ b/drivers/net/ovpn/socket.c
@@ -22,6 +22,9 @@ static void ovpn_socket_detach(struct socket *sock)
if (!sock)
return;
+ if (sock->sk->sk_protocol == IPPROTO_UDP)
+ ovpn_udp_socket_detach(sock);
+
sockfd_put(sock);
}
@@ -71,6 +74,27 @@ static int ovpn_socket_attach(struct socket *sock, struct ovpn_peer *peer)
return ret;
}
+/* Retrieve the corresponding ovpn object from a UDP socket
+ * rcu_read_lock must be held on entry
+ */
+struct ovpn_struct *ovpn_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;
+}
+
/**
* ovpn_socket_new - create a new socket and initialize it
* @sock: the kernel socket to embed
diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c
index 0b1a541732a2..8aea99520929 100644
--- a/drivers/net/ovpn/udp.c
+++ b/drivers/net/ovpn/udp.c
@@ -21,9 +21,94 @@
#include "bind.h"
#include "io.h"
#include "peer.h"
+#include "proto.h"
#include "socket.h"
#include "udp.h"
+/**
+ * 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 further processed,
+ * otherwise it 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_peer *peer = NULL;
+ struct ovpn_struct *ovpn;
+ u32 peer_id;
+ u8 opcode;
+
+ ovpn = ovpn_from_udp_sock(sk);
+ if (unlikely(!ovpn)) {
+ net_err_ratelimited("%s: cannot obtain ovpn object from UDP socket\n",
+ __func__);
+ goto drop;
+ }
+
+ /* 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_OP_SIZE_V2))) {
+ net_dbg_ratelimited("%s: packet too small\n", __func__);
+ 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_id(ovpn, peer_id);
+ if (!peer) {
+ net_err_ratelimited("%s: received data from unknown peer (id: %d)\n",
+ __func__, peer_id);
+ goto drop;
+ }
+ }
+
+ if (!peer) {
+ /* data packet with undef peer-id */
+ peer = ovpn_peer_get_by_transp_addr(ovpn, skb);
+ if (unlikely(!peer)) {
+ net_dbg_ratelimited("%s: received data with undef peer-id from unknown source\n",
+ __func__);
+ goto drop;
+ }
+ }
+
+ /* pop off outer UDP header */
+ __skb_pull(skb, sizeof(struct udphdr));
+ ovpn_recv(peer, skb);
+ return 0;
+
+drop:
+ if (peer)
+ ovpn_peer_put(peer);
+ dev_core_stats_rx_dropped_inc(ovpn->dev);
+ kfree_skb(skb);
+ return 0;
+}
+
/**
* ovpn_udp4_output - send IPv4 packet over udp socket
* @ovpn: the openvpn instance
@@ -257,8 +342,13 @@ void ovpn_udp_send_skb(struct ovpn_struct *ovpn, struct ovpn_peer *peer,
*/
int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_struct *ovpn)
{
+ struct udp_tunnel_sock_cfg cfg = {
+ .sk_user_data = ovpn,
+ .encap_type = UDP_ENCAP_OVPNINUDP,
+ .encap_rcv = ovpn_udp_encap_recv,
+ };
struct ovpn_socket *old_data;
- int ret = 0;
+ int ret;
/* sanity check */
if (sock->sk->sk_protocol != IPPROTO_UDP) {
@@ -272,6 +362,7 @@ int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_struct *ovpn)
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;
}
@@ -300,3 +391,14 @@ int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_struct *ovpn)
return ret;
}
+
+/**
+ * ovpn_udp_socket_detach - clean udp-tunnel status for this socket
+ * @sock: the socket to clean
+ */
+void ovpn_udp_socket_detach(struct socket *sock)
+{
+ struct udp_tunnel_sock_cfg cfg = { };
+
+ setup_udp_tunnel_sock(sock_net(sock->sk), sock, &cfg);
+}
diff --git a/drivers/net/ovpn/udp.h b/drivers/net/ovpn/udp.h
index e60f8cd2b4ac..fecb68464896 100644
--- a/drivers/net/ovpn/udp.h
+++ b/drivers/net/ovpn/udp.h
@@ -18,8 +18,9 @@ struct sk_buff;
struct socket;
int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_struct *ovpn);
-
+void ovpn_udp_socket_detach(struct socket *sock);
void ovpn_udp_send_skb(struct ovpn_struct *ovpn, struct ovpn_peer *peer,
struct sk_buff *skb);
+struct ovpn_struct *ovpn_from_udp_sock(struct sock *sk);
#endif /* _NET_OVPN_UDP_H_ */
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 11/25] ovpn: implement basic RX path (UDP)
2024-08-27 12:07 ` [PATCH net-next v6 11/25] ovpn: implement basic RX " Antonio Quartulli
@ 2024-09-02 11:22 ` Sabrina Dubroca
2024-09-02 12:24 ` Antonio Quartulli
2024-09-06 19:18 ` Simon Horman
1 sibling, 1 reply; 58+ messages in thread
From: Sabrina Dubroca @ 2024-09-02 11:22 UTC (permalink / raw)
To: Antonio Quartulli; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
2024-08-27, 14:07:51 +0200, Antonio Quartulli wrote:
> +static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb)
> +{
> + /* 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_probe_transport_header(skb);
> + skb_reset_inner_headers(skb);
> +
> + memset(skb->cb, 0, sizeof(skb->cb));
> +
> + /* cause packet to be "received" by the interface */
> + if (likely(gro_cells_receive(&peer->ovpn->gro_cells,
> + skb) == NET_RX_SUCCESS))
> + /* update RX stats with the size of decrypted packet */
> + dev_sw_netstats_rx_add(peer->ovpn->dev, skb->len);
I don't think accessing skb->len after passing the skb to
gro_cells_receive is safe, see
c7cc9200e9b4 ("macsec: avoid use-after-free in macsec_handle_frame()")
[...]
> static void ovpn_struct_free(struct net_device *net)
> {
> + struct ovpn_struct *ovpn = netdev_priv(net);
> +
> + gro_cells_destroy(&ovpn->gro_cells);
> + rcu_barrier();
What's the purpose of this rcu_barrier? I expect it in module_exit,
not when removing one netdevice.
> diff --git a/drivers/net/ovpn/skb.h b/drivers/net/ovpn/skb.h
> index 7966a10d915f..e070fe6f448c 100644
> --- a/drivers/net/ovpn/skb.h
> +++ b/drivers/net/ovpn/skb.h
> @@ -18,10 +18,7 @@
> #include <linux/types.h>
>
> struct ovpn_cb {
> - struct aead_request *req;
> struct ovpn_peer *peer;
> - struct ovpn_crypto_key_slot *ks;
> - unsigned int payload_offset;
Squashed into the wrong patch?
[...]
> +struct ovpn_struct *ovpn_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);
[1]
> + 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;
> +}
> +static int ovpn_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
> +{
> + struct ovpn_peer *peer = NULL;
> + struct ovpn_struct *ovpn;
> + u32 peer_id;
> + u8 opcode;
> +
> + ovpn = ovpn_from_udp_sock(sk);
> + if (unlikely(!ovpn)) {
> + net_err_ratelimited("%s: cannot obtain ovpn object from UDP socket\n",
> + __func__);
> + goto drop;
> + }
[...]
> + /* pop off outer UDP header */
> + __skb_pull(skb, sizeof(struct udphdr));
> + ovpn_recv(peer, skb);
> + return 0;
> +
> +drop:
> + if (peer)
> + ovpn_peer_put(peer);
> + dev_core_stats_rx_dropped_inc(ovpn->dev);
If we get here from the first goto, ovpn is NULL. You could add a
drop_noovpn label right here to just do the free+return.
> + kfree_skb(skb);
> + return 0;
> +}
> +
> /**
> * ovpn_udp4_output - send IPv4 packet over udp socket
> * @ovpn: the openvpn instance
> @@ -257,8 +342,13 @@ void ovpn_udp_send_skb(struct ovpn_struct *ovpn, struct ovpn_peer *peer,
> */
> int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_struct *ovpn)
> {
> + struct udp_tunnel_sock_cfg cfg = {
> + .sk_user_data = ovpn,
> + .encap_type = UDP_ENCAP_OVPNINUDP,
> + .encap_rcv = ovpn_udp_encap_recv,
> + };
> struct ovpn_socket *old_data;
> - int ret = 0;
> + int ret;
>
> /* sanity check */
> if (sock->sk->sk_protocol != IPPROTO_UDP) {
> @@ -272,6 +362,7 @@ int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_struct *ovpn)
> if (!old_data) {
> /* socket is currently unused - we can take it */
> rcu_read_unlock();
> + setup_udp_tunnel_sock(sock_net(sock->sk), sock, &cfg);
This will set sk_user_data to the ovpn_struct, but ovpn_from_udp_sock
expects the ovpn_socket [1], which is stored into sk_user_data a
little bit later by ovpn_socket_new. If a packet reaches
ovpn_udp_encap_recv -> ovpn_from_udp_sock before ovpn_socket_new
overwrites sk_user_data, bad things probably happen.
--
Sabrina
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 11/25] ovpn: implement basic RX path (UDP)
2024-09-02 11:22 ` Sabrina Dubroca
@ 2024-09-02 12:24 ` Antonio Quartulli
0 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-02 12:24 UTC (permalink / raw)
To: Sabrina Dubroca; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
On 02/09/2024 13:22, Sabrina Dubroca wrote:
> 2024-08-27, 14:07:51 +0200, Antonio Quartulli wrote:
>> +static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb)
>> +{
>> + /* 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_probe_transport_header(skb);
>> + skb_reset_inner_headers(skb);
>> +
>> + memset(skb->cb, 0, sizeof(skb->cb));
>> +
>> + /* cause packet to be "received" by the interface */
>> + if (likely(gro_cells_receive(&peer->ovpn->gro_cells,
>> + skb) == NET_RX_SUCCESS))
>> + /* update RX stats with the size of decrypted packet */
>> + dev_sw_netstats_rx_add(peer->ovpn->dev, skb->len);
>
> I don't think accessing skb->len after passing the skb to
> gro_cells_receive is safe, see
> c7cc9200e9b4 ("macsec: avoid use-after-free in macsec_handle_frame()")
Thanks for spotting this! It's basically the same issue (but symmetric)
as patch 10/25.
>
>
> [...]
>> static void ovpn_struct_free(struct net_device *net)
>> {
>> + struct ovpn_struct *ovpn = netdev_priv(net);
>> +
>> + gro_cells_destroy(&ovpn->gro_cells);
>> + rcu_barrier();
>
> What's the purpose of this rcu_barrier? I expect it in module_exit,
> not when removing one netdevice.
Good question.
I presume it's a leftover from previous tests.
I think it's harmless, but it should not be needed at all.
I will remove it.
>
>
>> diff --git a/drivers/net/ovpn/skb.h b/drivers/net/ovpn/skb.h
>> index 7966a10d915f..e070fe6f448c 100644
>> --- a/drivers/net/ovpn/skb.h
>> +++ b/drivers/net/ovpn/skb.h
>> @@ -18,10 +18,7 @@
>> #include <linux/types.h>
>>
>> struct ovpn_cb {
>> - struct aead_request *req;
>> struct ovpn_peer *peer;
>> - struct ovpn_crypto_key_slot *ks;
>> - unsigned int payload_offset;
>
> Squashed into the wrong patch?
Darn yes. Sorry for this.
>
>
> [...]
>> +struct ovpn_struct *ovpn_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);
>
> [1]
>
>> + 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;
>> +}
>
>
>> +static int ovpn_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
>> +{
>> + struct ovpn_peer *peer = NULL;
>> + struct ovpn_struct *ovpn;
>> + u32 peer_id;
>> + u8 opcode;
>> +
>> + ovpn = ovpn_from_udp_sock(sk);
>> + if (unlikely(!ovpn)) {
>> + net_err_ratelimited("%s: cannot obtain ovpn object from UDP socket\n",
>> + __func__);
>> + goto drop;
>> + }
> [...]
>> + /* pop off outer UDP header */
>> + __skb_pull(skb, sizeof(struct udphdr));
>> + ovpn_recv(peer, skb);
>> + return 0;
>> +
>> +drop:
>> + if (peer)
>> + ovpn_peer_put(peer);
>> + dev_core_stats_rx_dropped_inc(ovpn->dev);
>
> If we get here from the first goto, ovpn is NULL. You could add a
> drop_noovpn label right here to just do the free+return.
Right.
Weird though that no static analysis tool complained about ovpn possibly
being NULL.
Will add the extra label.
>
>> + kfree_skb(skb);
>> + return 0;
>> +}
>> +
>> /**
>> * ovpn_udp4_output - send IPv4 packet over udp socket
>> * @ovpn: the openvpn instance
>> @@ -257,8 +342,13 @@ void ovpn_udp_send_skb(struct ovpn_struct *ovpn, struct ovpn_peer *peer,
>> */
>> int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_struct *ovpn)
>> {
>> + struct udp_tunnel_sock_cfg cfg = {
>> + .sk_user_data = ovpn,
>> + .encap_type = UDP_ENCAP_OVPNINUDP,
>> + .encap_rcv = ovpn_udp_encap_recv,
>> + };
>> struct ovpn_socket *old_data;
>> - int ret = 0;
>> + int ret;
>>
>> /* sanity check */
>> if (sock->sk->sk_protocol != IPPROTO_UDP) {
>> @@ -272,6 +362,7 @@ int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_struct *ovpn)
>> if (!old_data) {
>> /* socket is currently unused - we can take it */
>> rcu_read_unlock();
>> + setup_udp_tunnel_sock(sock_net(sock->sk), sock, &cfg);
>
> This will set sk_user_data to the ovpn_struct, but ovpn_from_udp_sock
> expects the ovpn_socket [1], which is stored into sk_user_data a
> little bit later by ovpn_socket_new. If a packet reaches
> ovpn_udp_encap_recv -> ovpn_from_udp_sock before ovpn_socket_new
> overwrites sk_user_data, bad things probably happen.
Wow - this is a very nice catch.
I think this wrong cfg.sk_user_data initialization was there this since
the first prototype, but it just passed unnoticed.
I will drop the field initialization, so that the sk_user_data stays
NULL until it gets assigned the ovpn_sock.
Thanks a lot!
Cheers,
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread
* Re: [PATCH net-next v6 11/25] ovpn: implement basic RX path (UDP)
2024-08-27 12:07 ` [PATCH net-next v6 11/25] ovpn: implement basic RX " Antonio Quartulli
2024-09-02 11:22 ` Sabrina Dubroca
@ 2024-09-06 19:18 ` Simon Horman
2024-09-09 8:37 ` Antonio Quartulli
1 sibling, 1 reply; 58+ messages in thread
From: Simon Horman @ 2024-09-06 19:18 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd
On Tue, Aug 27, 2024 at 02:07:51PM +0200, Antonio Quartulli wrote:
> 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>
...
> +/**
> + * 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 further processed,
> + * otherwise it 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_peer *peer = NULL;
> + struct ovpn_struct *ovpn;
> + u32 peer_id;
> + u8 opcode;
> +
> + ovpn = ovpn_from_udp_sock(sk);
> + if (unlikely(!ovpn)) {
> + net_err_ratelimited("%s: cannot obtain ovpn object from UDP socket\n",
> + __func__);
> + goto drop;
Hi Antonio,
Here ovpn is NULL. But jumping to drop will result in ovpn being dereferenced.
Flagged by Smatch.
> + }
> +
> + /* 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_OP_SIZE_V2))) {
> + net_dbg_ratelimited("%s: packet too small\n", __func__);
> + 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_id(ovpn, peer_id);
> + if (!peer) {
> + net_err_ratelimited("%s: received data from unknown peer (id: %d)\n",
> + __func__, peer_id);
> + goto drop;
> + }
> + }
> +
> + if (!peer) {
> + /* data packet with undef peer-id */
> + peer = ovpn_peer_get_by_transp_addr(ovpn, skb);
> + if (unlikely(!peer)) {
> + net_dbg_ratelimited("%s: received data with undef peer-id from unknown source\n",
> + __func__);
> + goto drop;
> + }
> + }
> +
> + /* pop off outer UDP header */
> + __skb_pull(skb, sizeof(struct udphdr));
> + ovpn_recv(peer, skb);
> + return 0;
> +
> +drop:
> + if (peer)
> + ovpn_peer_put(peer);
> + dev_core_stats_rx_dropped_inc(ovpn->dev);
> + kfree_skb(skb);
> + return 0;
> +}
> +
...
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 11/25] ovpn: implement basic RX path (UDP)
2024-09-06 19:18 ` Simon Horman
@ 2024-09-09 8:37 ` Antonio Quartulli
0 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-09 8:37 UTC (permalink / raw)
To: Simon Horman; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd
On 06/09/2024 21:18, Simon Horman wrote:
> On Tue, Aug 27, 2024 at 02:07:51PM +0200, Antonio Quartulli wrote:
>> 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>
>
> ...
>
>> +/**
>> + * 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 further processed,
>> + * otherwise it 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_peer *peer = NULL;
>> + struct ovpn_struct *ovpn;
>> + u32 peer_id;
>> + u8 opcode;
>> +
>> + ovpn = ovpn_from_udp_sock(sk);
>> + if (unlikely(!ovpn)) {
>> + net_err_ratelimited("%s: cannot obtain ovpn object from UDP socket\n",
>> + __func__);
>> + goto drop;
>
> Hi Antonio,
>
> Here ovpn is NULL. But jumping to drop will result in ovpn being dereferenced.
>
> Flagged by Smatch.
You are correct, thanks for the report.
Will fix it in the next version.
Cheers,
>
>
>> + }
>> +
>> + /* 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_OP_SIZE_V2))) {
>> + net_dbg_ratelimited("%s: packet too small\n", __func__);
>> + 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_id(ovpn, peer_id);
>> + if (!peer) {
>> + net_err_ratelimited("%s: received data from unknown peer (id: %d)\n",
>> + __func__, peer_id);
>> + goto drop;
>> + }
>> + }
>> +
>> + if (!peer) {
>> + /* data packet with undef peer-id */
>> + peer = ovpn_peer_get_by_transp_addr(ovpn, skb);
>> + if (unlikely(!peer)) {
>> + net_dbg_ratelimited("%s: received data with undef peer-id from unknown source\n",
>> + __func__);
>> + goto drop;
>> + }
>> + }
>> +
>> + /* pop off outer UDP header */
>> + __skb_pull(skb, sizeof(struct udphdr));
>> + ovpn_recv(peer, skb);
>> + return 0;
>> +
>> +drop:
>> + if (peer)
>> + ovpn_peer_put(peer);
>> + dev_core_stats_rx_dropped_inc(ovpn->dev);
>> + kfree_skb(skb);
>> + return 0;
>> +}
>> +
>
> ...
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread
* [PATCH net-next v6 12/25] ovpn: implement packet processing
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (10 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 11/25] ovpn: implement basic RX " Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-09-02 14:42 ` Sabrina Dubroca
2024-09-06 19:29 ` Simon Horman
2024-08-27 12:07 ` [PATCH net-next v6 13/25] ovpn: store tunnel and transport statistics Antonio Quartulli
` (12 subsequent siblings)
24 siblings, 2 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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/ovpn/Makefile | 3 +
drivers/net/ovpn/crypto.c | 149 +++++++++++++
drivers/net/ovpn/crypto.h | 136 ++++++++++++
drivers/net/ovpn/crypto_aead.c | 374 +++++++++++++++++++++++++++++++++
drivers/net/ovpn/crypto_aead.h | 31 +++
drivers/net/ovpn/io.c | 124 ++++++++++-
drivers/net/ovpn/io.h | 3 +
drivers/net/ovpn/packet.h | 2 +-
drivers/net/ovpn/peer.c | 29 +++
drivers/net/ovpn/peer.h | 6 +
drivers/net/ovpn/pktid.c | 130 ++++++++++++
drivers/net/ovpn/pktid.h | 87 ++++++++
drivers/net/ovpn/proto.h | 31 +++
drivers/net/ovpn/skb.h | 11 +-
14 files changed, 1103 insertions(+), 13 deletions(-)
create mode 100644 drivers/net/ovpn/crypto.c
create mode 100644 drivers/net/ovpn/crypto.h
create mode 100644 drivers/net/ovpn/crypto_aead.c
create mode 100644 drivers/net/ovpn/crypto_aead.h
create mode 100644 drivers/net/ovpn/pktid.c
create mode 100644 drivers/net/ovpn/pktid.h
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
index 56bddc9bef83..ccdaeced1982 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/crypto.c b/drivers/net/ovpn/crypto.c
new file mode 100644
index 000000000000..0bceaef32f5b
--- /dev/null
+++ b/drivers/net/ovpn/crypto.c
@@ -0,0 +1,149 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 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 "ovpnstruct.h"
+#include "main.h"
+#include "packet.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->primary);
+ if (ks) {
+ RCU_INIT_POINTER(cs->primary, NULL);
+ ovpn_crypto_key_slot_put(ks);
+ }
+
+ ks = rcu_access_pointer(cs->secondary);
+ if (ks) {
+ RCU_INIT_POINTER(cs->secondary, NULL);
+ ovpn_crypto_key_slot_put(ks);
+ }
+
+ mutex_destroy(&cs->mutex);
+}
+
+/* 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;
+
+ 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);
+
+ mutex_lock(&cs->mutex);
+ switch (pkr->slot) {
+ case OVPN_KEY_SLOT_PRIMARY:
+ old = rcu_replace_pointer(cs->primary, new,
+ lockdep_is_held(&cs->mutex));
+ break;
+ case OVPN_KEY_SLOT_SECONDARY:
+ old = rcu_replace_pointer(cs->secondary, new,
+ lockdep_is_held(&cs->mutex));
+ break;
+ }
+ mutex_unlock(&cs->mutex);
+
+ 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;
+
+ if (slot != OVPN_KEY_SLOT_PRIMARY &&
+ slot != OVPN_KEY_SLOT_SECONDARY) {
+ pr_warn("Invalid slot to release: %u\n", slot);
+ return;
+ }
+
+ mutex_lock(&cs->mutex);
+ switch (slot) {
+ case OVPN_KEY_SLOT_PRIMARY:
+ ks = rcu_replace_pointer(cs->primary, NULL,
+ lockdep_is_held(&cs->mutex));
+ break;
+ case OVPN_KEY_SLOT_SECONDARY:
+ ks = rcu_replace_pointer(cs->secondary, NULL,
+ lockdep_is_held(&cs->mutex));
+ break;
+ }
+ mutex_unlock(&cs->mutex);
+
+ 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;
+
+ mutex_lock(&cs->mutex);
+
+ old_secondary = rcu_dereference_protected(cs->secondary,
+ lockdep_is_held(&cs->mutex));
+ old_primary = rcu_replace_pointer(cs->primary, old_secondary,
+ lockdep_is_held(&cs->mutex));
+ rcu_assign_pointer(cs->secondary, old_primary);
+
+ pr_debug("key swapped: %u <-> %u\n",
+ old_primary ? old_primary->key_id : 0,
+ old_secondary ? old_secondary->key_id : 0);
+
+ mutex_unlock(&cs->mutex);
+}
diff --git a/drivers/net/ovpn/crypto.h b/drivers/net/ovpn/crypto.h
new file mode 100644
index 000000000000..228833db51a1
--- /dev/null
+++ b/drivers/net/ovpn/crypto.h
@@ -0,0 +1,136 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 OpenVPN, Inc.
+ *
+ * Author: James Yonan <james@openvpn.net>
+ * Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_OVPNCRYPTO_H_
+#define _NET_OVPN_OVPNCRYPTO_H_
+
+struct ovpn_peer;
+struct ovpn_crypto_key_slot;
+
+/* 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;
+ struct ovpn_nonce_tail nonce_tail_xmit;
+ struct ovpn_nonce_tail nonce_tail_recv;
+
+ 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 *primary;
+ struct ovpn_crypto_key_slot __rcu *secondary;
+
+ /* protects primary and secondary slots */
+ struct mutex mutex;
+};
+
+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->primary, NULL);
+ RCU_INIT_POINTER(cs->secondary, NULL);
+ mutex_init(&cs->mutex);
+}
+
+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;
+
+ if (unlikely(!cs))
+ return NULL;
+
+ rcu_read_lock();
+ ks = rcu_dereference(cs->primary);
+ if (ks && ks->key_id == key_id) {
+ if (unlikely(!ovpn_crypto_key_slot_hold(ks)))
+ ks = NULL;
+ goto out;
+ }
+
+ ks = rcu_dereference(cs->secondary);
+ 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->primary);
+ 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 000000000000..2e36ba8c4bfd
--- /dev/null
+++ b/drivers/net/ovpn/crypto_aead.c
@@ -0,0 +1,374 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 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 "ovpnstruct.h"
+#include "main.h"
+#include "io.h"
+#include "packet.h"
+#include "pktid.h"
+#include "crypto_aead.h"
+#include "crypto.h"
+#include "peer.h"
+#include "proto.h"
+#include "skb.h"
+
+#define AUTH_TAG_SIZE 16
+
+static int ovpn_aead_encap_overhead(const struct ovpn_crypto_key_slot *ks)
+{
+ return OVPN_OP_SIZE_V2 + /* OP header size */
+ 4 + /* Packet ID */
+ crypto_aead_authsize(ks->encrypt); /* Auth Tag */
+}
+
+static void ovpn_aead_encrypt_done(void *data, int ret)
+{
+ struct sk_buff *skb = data;
+
+ aead_request_free(ovpn_skb_cb(skb)->ctx->req);
+ ovpn_encrypt_post(skb, ret);
+}
+
+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);
+ const unsigned int head_size = ovpn_aead_encap_overhead(ks);
+ DECLARE_CRYPTO_WAIT(wait);
+ struct aead_request *req;
+ struct sk_buff *trailer;
+ struct scatterlist *sg;
+ u8 iv[NONCE_SIZE];
+ int nfrags, ret;
+ u32 pktid, op;
+
+ /* 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, after adding network header and encryption overhead
+ */
+ if (unlikely(skb_cow_head(skb, OVPN_HEAD_ROOM + head_size)))
+ 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;
+
+ ovpn_skb_cb(skb)->ctx = kmalloc(sizeof(*ovpn_skb_cb(skb)->ctx),
+ GFP_ATOMIC);
+ if (unlikely(!ovpn_skb_cb(skb)->ctx))
+ return -ENOMEM;
+
+ sg = ovpn_skb_cb(skb)->ctx->sg;
+
+ /* sg table:
+ * 0: op, wire nonce (AD, len=OVPN_OP_SIZE_V2+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)) {
+ kfree(sg);
+ return -EINVAL;
+ }
+
+ /* 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)) {
+ kfree(ovpn_skb_cb(skb)->ctx);
+ return ret;
+ }
+
+ /* 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, NONCE_WIRE_SIZE);
+ memcpy(skb->data, iv, 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_OP_SIZE_V2);
+ BUILD_BUG_ON(sizeof(op) != OVPN_OP_SIZE_V2);
+ *((__force __be32 *)skb->data) = htonl(op);
+
+ /* AEAD Additional data */
+ sg_set_buf(sg, skb->data, OVPN_OP_SIZE_V2 + NONCE_WIRE_SIZE);
+
+ req = aead_request_alloc(ks->encrypt, GFP_ATOMIC);
+ if (unlikely(!req)) {
+ kfree(ovpn_skb_cb(skb)->ctx);
+ return -ENOMEM;
+ }
+
+ /* setup async crypto operation */
+ aead_request_set_tfm(req, ks->encrypt);
+ aead_request_set_callback(req, 0, ovpn_aead_encrypt_done, skb);
+ aead_request_set_crypt(req, sg, sg, skb->len - head_size, iv);
+ aead_request_set_ad(req, OVPN_OP_SIZE_V2 + NONCE_WIRE_SIZE);
+
+ ovpn_skb_cb(skb)->ctx->peer = peer;
+ ovpn_skb_cb(skb)->ctx->req = req;
+ ovpn_skb_cb(skb)->ctx->ks = ks;
+
+ /* encrypt it */
+ return crypto_aead_encrypt(req);
+}
+
+static void ovpn_aead_decrypt_done(void *data, int ret)
+{
+ struct sk_buff *skb = data;
+
+ aead_request_free(ovpn_skb_cb(skb)->ctx->req);
+ ovpn_decrypt_post(skb, 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;
+ DECLARE_CRYPTO_WAIT(wait);
+ struct aead_request *req;
+ struct sk_buff *trailer;
+ struct scatterlist *sg;
+ unsigned int sg_len;
+ u8 iv[NONCE_SIZE];
+
+ payload_offset = OVPN_OP_SIZE_V2 + NONCE_WIRE_SIZE + tag_size;
+ payload_len = skb->len - payload_offset;
+
+ /* 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;
+
+ ovpn_skb_cb(skb)->ctx = kmalloc(sizeof(*ovpn_skb_cb(skb)->ctx),
+ GFP_ATOMIC);
+ if (unlikely(!ovpn_skb_cb(skb)->ctx))
+ return -ENOMEM;
+
+ sg = ovpn_skb_cb(skb)->ctx->sg;
+
+ /* sg table:
+ * 0: op, wire nonce (AD, len=OVPN_OP_SIZE_V2+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_len = OVPN_OP_SIZE_V2 + NONCE_WIRE_SIZE;
+ sg_set_buf(sg, skb->data, sg_len);
+
+ /* build scatterlist to decrypt packet payload */
+ ret = skb_to_sgvec_nomark(skb, sg + 1, payload_offset, payload_len);
+ if (unlikely(nfrags != ret)) {
+ kfree(ovpn_skb_cb(skb)->ctx);
+ return -EINVAL;
+ }
+
+ /* append auth_tag onto scatterlist */
+ sg_set_buf(sg + nfrags + 1, skb->data + sg_len, tag_size);
+
+ /* copy nonce into IV buffer */
+ memcpy(iv, skb->data + OVPN_OP_SIZE_V2, NONCE_WIRE_SIZE);
+ memcpy(iv + NONCE_WIRE_SIZE, ks->nonce_tail_recv.u8,
+ sizeof(struct ovpn_nonce_tail));
+
+ req = aead_request_alloc(ks->decrypt, GFP_ATOMIC);
+ if (unlikely(!req)) {
+ kfree(ovpn_skb_cb(skb)->ctx);
+ return -ENOMEM;
+ }
+
+ /* setup async crypto operation */
+ aead_request_set_tfm(req, ks->decrypt);
+ aead_request_set_callback(req, 0, ovpn_aead_decrypt_done, skb);
+ aead_request_set_crypt(req, sg, sg, payload_len + tag_size, iv);
+
+ aead_request_set_ad(req, NONCE_WIRE_SIZE + OVPN_OP_SIZE_V2);
+
+ ovpn_skb_cb(skb)->ctx->payload_offset = payload_offset;
+ ovpn_skb_cb(skb)->ctx->peer = peer;
+ ovpn_skb_cb(skb)->ctx->req = req;
+ ovpn_skb_cb(skb)->ctx->ks = ks;
+
+ /* decrypt it */
+ return crypto_aead_decrypt(req);
+}
+
+/* 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, 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) != NONCE_SIZE) {
+ pr_err("%s IV size must be %d\n", title, 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 = "gcm(aes)";
+ break;
+ case OVPN_CIPHER_ALG_CHACHA20_POLY1305:
+ alg_name = "rfc7539(chacha20,poly1305)";
+ break;
+ default:
+ return ERR_PTR(-EOPNOTSUPP);
+ }
+
+ if (sizeof(struct ovpn_nonce_tail) != kc->encrypt.nonce_tail_size ||
+ sizeof(struct ovpn_nonce_tail) != kc->decrypt.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.u8, kc->encrypt.nonce_tail,
+ sizeof(struct ovpn_nonce_tail));
+ memcpy(ks->nonce_tail_recv.u8, kc->decrypt.nonce_tail,
+ sizeof(struct ovpn_nonce_tail));
+
+ /* 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 000000000000..77ee8141599b
--- /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) 2020-2024 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 ad986c66dbdf..2b9311566971 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -15,6 +15,8 @@
#include "ovpnstruct.h"
#include "peer.h"
#include "io.h"
+#include "crypto.h"
+#include "crypto_aead.h"
#include "netlink.h"
#include "proto.h"
#include "udp.h"
@@ -54,39 +56,122 @@ static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb)
dev_sw_netstats_rx_add(peer->ovpn->dev, skb->len);
}
-static void ovpn_decrypt_post(struct sk_buff *skb, int ret)
+void ovpn_decrypt_post(struct sk_buff *skb, int ret)
{
- struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;
+ struct ovpn_crypto_key_slot *ks = ovpn_skb_cb(skb)->ctx->ks;
+ struct ovpn_peer *peer = ovpn_skb_cb(skb)->ctx->peer;
+ __be16 proto;
+ __be32 *pid;
- if (unlikely(ret < 0))
+ /* crypto is happening asyncronously. this function will be called
+ * again later by the crypto callback with a proper return code
+ */
+ if (unlikely(ret == -EINPROGRESS))
+ return;
+
+ if (unlikely(ret < 0)) {
+ net_err_ratelimited("%s: error during decryption for peer %u, key-id %u: %d\n",
+ peer->ovpn->dev->name, peer->id, ks->key_id,
+ ret);
+ goto drop;
+ }
+
+ /* PID sits after the op */
+ pid = (__force __be32 *)(skb->data + OVPN_OP_SIZE_V2);
+ ret = ovpn_pktid_recv(&ks->pid_recv, ntohl(*pid), 0);
+ if (unlikely(ret < 0)) {
+ net_err_ratelimited("%s: PKT ID RX error: %d\n",
+ peer->ovpn->dev->name, ret);
goto drop;
+ }
+ /* point to encapsulated IP packet */
+ __skb_pull(skb, ovpn_skb_cb(skb)->ctx->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",
+ peer->ovpn->dev->name, peer->id);
+ goto drop;
+ }
+
+ net_info_ratelimited("%s: unsupported protocol received from peer %u\n",
+ peer->ovpn->dev->name, 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_to_family(skb) == AF_INET6)
+ net_dbg_ratelimited("%s: RPF dropped packet from peer %u, src: %pI6c\n",
+ peer->ovpn->dev->name, peer->id,
+ &ipv6_hdr(skb)->saddr);
+ else
+ net_dbg_ratelimited("%s: RPF dropped packet from peer %u, src: %pI4\n",
+ peer->ovpn->dev->name, peer->id,
+ &ip_hdr(skb)->saddr);
+ goto drop;
+ }
+
+ kfree(ovpn_skb_cb(skb)->ctx);
ovpn_netdev_write(peer, skb);
/* skb is passed to upper layer - don't free it */
skb = NULL;
drop:
- if (unlikely(skb))
+ if (unlikely(skb)) {
dev_core_stats_rx_dropped_inc(peer->ovpn->dev);
+ kfree(ovpn_skb_cb(skb)->ctx);
+ }
kfree_skb(skb);
+ ovpn_crypto_key_slot_put(ks);
ovpn_peer_put(peer);
}
/* pick next packet from RX queue, decrypt 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",
+ peer->ovpn->dev->name, peer->id, key_id);
+ dev_core_stats_rx_dropped_inc(peer->ovpn->dev);
+ kfree_skb(skb);
+ return;
+ }
+
+ 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(struct sk_buff *skb, int ret)
{
- struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;
+ struct ovpn_crypto_key_slot *ks = ovpn_skb_cb(skb)->ctx->ks;
+ struct ovpn_peer *peer = ovpn_skb_cb(skb)->ctx->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;
if (unlikely(ret < 0))
goto err;
skb_mark_not_on_list(skb);
+ kfree(ovpn_skb_cb(skb)->ctx);
+
switch (peer->sock->sock->sk->sk_protocol) {
case IPPROTO_UDP:
ovpn_udp_send_skb(peer->ovpn, peer, skb);
@@ -100,14 +185,31 @@ static void ovpn_encrypt_post(struct sk_buff *skb, int ret)
err:
if (unlikely(skb)) {
dev_core_stats_tx_dropped_inc(peer->ovpn->dev);
- kfree_skb(skb);
+ kfree(ovpn_skb_cb(skb)->ctx);
}
+ kfree_skb(skb);
+ ovpn_crypto_key_slot_put(ks);
ovpn_peer_put(peer);
}
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\n",
+ peer->ovpn->dev->name);
+ return false;
+ }
+
+ /* get primary key to be used for encrypting data */
+ ks = ovpn_crypto_key_slot_primary(&peer->crypto);
+ if (unlikely(!ks)) {
+ net_warn_ratelimited("%s: error while retrieving primary key slot for peer %u\n",
+ peer->ovpn->dev->name, peer->id);
+ return false;
+ }
/* take a reference to the peer because the crypto code may run async.
* ovpn_encrypt_post() will release it upon completion
@@ -117,7 +219,7 @@ static bool ovpn_encrypt_one(struct ovpn_peer *peer, struct sk_buff *skb)
return false;
}
- ovpn_encrypt_post(skb, 0);
+ 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 9667a0a470e0..ad741552d742 100644
--- a/drivers/net/ovpn/io.h
+++ b/drivers/net/ovpn/io.h
@@ -14,4 +14,7 @@ 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(struct sk_buff *skb, int ret);
+void ovpn_decrypt_post(struct sk_buff *skb, int ret);
+
#endif /* _NET_OVPN_OVPN_H_ */
diff --git a/drivers/net/ovpn/packet.h b/drivers/net/ovpn/packet.h
index 7ed146f5932a..e14c9bf464f7 100644
--- a/drivers/net/ovpn/packet.h
+++ b/drivers/net/ovpn/packet.h
@@ -10,7 +10,7 @@
#ifndef _NET_OVPN_PACKET_H_
#define _NET_OVPN_PACKET_H_
-/* When the OpenVPN protocol is ran in AEAD mode, use
+/* When the OpenVPN protocol is run in AEAD mode, use
* the OpenVPN packet ID as the AEAD nonce:
*
* 00000005 521c3b01 4308c041
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 6bde4bd9395b..212d1210bc56 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -12,6 +12,8 @@
#include "ovpnstruct.h"
#include "bind.h"
+#include "pktid.h"
+#include "crypto.h"
#include "io.h"
#include "main.h"
#include "netlink.h"
@@ -42,6 +44,7 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_struct *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);
@@ -67,6 +70,7 @@ static void ovpn_peer_release(struct ovpn_peer *peer)
if (peer->sock)
ovpn_socket_put(peer->sock);
+ ovpn_crypto_state_release(&peer->crypto);
ovpn_bind_reset(peer, NULL);
dst_cache_destroy(&peer->dst_cache);
}
@@ -277,6 +281,31 @@ struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_struct *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_struct *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
+ */
+ rcu_read_lock();
+ match = (peer == rcu_dereference(ovpn->peer));
+ rcu_read_unlock();
+ }
+
+ 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 37de5aff54a8..70d92cd5bd63 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -11,6 +11,8 @@
#define _NET_OVPN_OVPNPEER_H_
#include "bind.h"
+#include "pktid.h"
+#include "crypto.h"
#include "socket.h"
#include <net/dst_cache.h>
@@ -24,6 +26,7 @@
* @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
* @halt: true if ovpn_peer_mark_delete was called
@@ -41,6 +44,7 @@ struct ovpn_peer {
struct in6_addr ipv6;
} vpn_addrs;
struct ovpn_socket *sock;
+ struct ovpn_crypto_state crypto;
struct dst_cache dst_cache;
struct ovpn_bind __rcu *bind;
bool halt;
@@ -83,5 +87,7 @@ struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_struct *ovpn,
struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_struct *ovpn, u32 peer_id);
struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_struct *ovpn,
struct sk_buff *skb);
+bool ovpn_peer_check_by_src(struct ovpn_struct *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 000000000000..96dc87635670
--- /dev/null
+++ b/drivers/net/ovpn/pktid.c
@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 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 "ovpnstruct.h"
+#include "main.h"
+#include "packet.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 000000000000..fe02f0667e1a
--- /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) 2020-2024 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ * James Yonan <james@openvpn.net>
+ */
+
+#ifndef _NET_OVPN_OVPNPKTID_H_
+#define _NET_OVPN_OVPNPKTID_H_
+
+#include "packet.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 struct ovpn_nonce_tail *nt,
+ unsigned char *dest)
+{
+ *(__force __be32 *)(dest) = htonl(pktid);
+ BUILD_BUG_ON(4 + sizeof(struct ovpn_nonce_tail) != NONCE_SIZE);
+ memcpy(dest + 4, nt->u8, sizeof(struct ovpn_nonce_tail));
+}
+
+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 69604cf26bbf..32af6b8e5743 100644
--- a/drivers/net/ovpn/proto.h
+++ b/drivers/net/ovpn/proto.h
@@ -72,4 +72,35 @@ static inline u32 ovpn_peer_id_from_skb(const struct sk_buff *skb, u16 offset)
return ntohl(*(__be32 *)(skb->data + offset)) & OVPN_PEER_ID_MASK;
}
+/**
+ * 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)
+{
+ return *skb->data & OVPN_KEY_ID_MASK;
+}
+
+/**
+ * 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)
+{
+ const u8 op = (opcode << OVPN_OPCODE_SHIFT) |
+ (key_id & OVPN_KEY_ID_MASK);
+
+ return (op << 24) | (peer_id & OVPN_PEER_ID_MASK);
+}
+
#endif /* _NET_OVPN_OVPNPROTO_H_ */
diff --git a/drivers/net/ovpn/skb.h b/drivers/net/ovpn/skb.h
index e070fe6f448c..3f94efae20fb 100644
--- a/drivers/net/ovpn/skb.h
+++ b/drivers/net/ovpn/skb.h
@@ -17,8 +17,17 @@
#include <linux/socket.h>
#include <linux/types.h>
-struct ovpn_cb {
+struct ovpn_cb_ctx {
struct ovpn_peer *peer;
+ struct sk_buff *skb;
+ struct ovpn_crypto_key_slot *ks;
+ struct aead_request *req;
+ struct scatterlist sg[MAX_SKB_FRAGS + 2];
+ unsigned int payload_offset;
+};
+
+struct ovpn_cb {
+ struct ovpn_cb_ctx *ctx;
};
static inline struct ovpn_cb *ovpn_skb_cb(struct sk_buff *skb)
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 12/25] ovpn: implement packet processing
2024-08-27 12:07 ` [PATCH net-next v6 12/25] ovpn: implement packet processing Antonio Quartulli
@ 2024-09-02 14:42 ` Sabrina Dubroca
2024-09-04 12:07 ` Antonio Quartulli
2024-09-06 19:29 ` Simon Horman
1 sibling, 1 reply; 58+ messages in thread
From: Sabrina Dubroca @ 2024-09-02 14:42 UTC (permalink / raw)
To: Antonio Quartulli; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
2024-08-27, 14:07:52 +0200, Antonio Quartulli wrote:
> +/* this swap is not atomic, but there will be a very short time frame where the
Since we're under a mutex, I think we might get put to sleep for a
not-so-short time frame.
> + * old_secondary key won't be available. This should not be a big deal as most
I could be misreading the code, but isn't it old_primary that's
unavailable during the swap? rcu_replace_pointer overwrites
cs->primary, so before the final assign, both slots contain
old_secondary?
> + * 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;
> +
> + mutex_lock(&cs->mutex);
> +
> + old_secondary = rcu_dereference_protected(cs->secondary,
> + lockdep_is_held(&cs->mutex));
> + old_primary = rcu_replace_pointer(cs->primary, old_secondary,
> + lockdep_is_held(&cs->mutex));
> + rcu_assign_pointer(cs->secondary, old_primary);
> +
> + pr_debug("key swapped: %u <-> %u\n",
> + old_primary ? old_primary->key_id : 0,
> + old_secondary ? old_secondary->key_id : 0);
> +
> + mutex_unlock(&cs->mutex);
> +}
[...]
> +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);
> + const unsigned int head_size = ovpn_aead_encap_overhead(ks);
> + DECLARE_CRYPTO_WAIT(wait);
nit: unused
> + struct aead_request *req;
> + struct sk_buff *trailer;
> + struct scatterlist *sg;
> + u8 iv[NONCE_SIZE];
> + int nfrags, ret;
> + u32 pktid, op;
> +
> + /* 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, after adding network header and encryption overhead
> + */
> + if (unlikely(skb_cow_head(skb, OVPN_HEAD_ROOM + head_size)))
> + 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;
> +
> + ovpn_skb_cb(skb)->ctx = kmalloc(sizeof(*ovpn_skb_cb(skb)->ctx),
> + GFP_ATOMIC);
> + if (unlikely(!ovpn_skb_cb(skb)->ctx))
> + return -ENOMEM;
I think you should clear skb->cb (or at least ->ctx) at the start of
ovpn_aead_encrypt. I don't think it will be cleaned up by the previous
user, and if we fail before this alloc, we will possibly have bogus
values in ->ctx when we get to kfree(ovpn_skb_cb(skb)->ctx) at the end
of ovpn_encrypt_post.
(Similar comments around cb/ctx freeing and initialization apply to
ovpn_aead_decrypt and ovpn_decrypt_post)
> + sg = ovpn_skb_cb(skb)->ctx->sg;
> +
> + /* sg table:
> + * 0: op, wire nonce (AD, len=OVPN_OP_SIZE_V2+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)) {
> + kfree(sg);
This is the only location in this function (and ovpn_encrypt_post)
that frees sg. Is that correct? sg points to an array contained within
->ctx, I don't think you want to free that directly.
> + return -EINVAL;
> + }
> +
> + /* 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)) {
> + kfree(ovpn_skb_cb(skb)->ctx);
Isn't that going to cause a double-free when we get to the end of
ovpn_encrypt_post? Or even UAF when we try to get ks/peer at the
start?
> + return ret;
> + }
> +
> + /* 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, NONCE_WIRE_SIZE);
> + memcpy(skb->data, iv, 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_OP_SIZE_V2);
> + BUILD_BUG_ON(sizeof(op) != OVPN_OP_SIZE_V2);
> + *((__force __be32 *)skb->data) = htonl(op);
> +
> + /* AEAD Additional data */
> + sg_set_buf(sg, skb->data, OVPN_OP_SIZE_V2 + NONCE_WIRE_SIZE);
> +
> + req = aead_request_alloc(ks->encrypt, GFP_ATOMIC);
> + if (unlikely(!req)) {
> + kfree(ovpn_skb_cb(skb)->ctx);
Same here.
> + return -ENOMEM;
> + }
> +
> + /* setup async crypto operation */
> + aead_request_set_tfm(req, ks->encrypt);
> + aead_request_set_callback(req, 0, ovpn_aead_encrypt_done, skb);
> + aead_request_set_crypt(req, sg, sg, skb->len - head_size, iv);
> + aead_request_set_ad(req, OVPN_OP_SIZE_V2 + NONCE_WIRE_SIZE);
> +
> + ovpn_skb_cb(skb)->ctx->peer = peer;
> + ovpn_skb_cb(skb)->ctx->req = req;
> + ovpn_skb_cb(skb)->ctx->ks = ks;
> +
> + /* encrypt it */
> + return crypto_aead_encrypt(req);
> +}
> +
> +static void ovpn_aead_decrypt_done(void *data, int ret)
> +{
> + struct sk_buff *skb = data;
> +
> + aead_request_free(ovpn_skb_cb(skb)->ctx->req);
This function only gets called in the async case. Where's the
corresponding aead_request_free in the sync case? (same for encrypt)
This should be moved into ovpn_decrypt_post, I think.
> + ovpn_decrypt_post(skb, 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;
> + DECLARE_CRYPTO_WAIT(wait);
nit: unused
[...]
> -static void ovpn_encrypt_post(struct sk_buff *skb, int ret)
> +void ovpn_encrypt_post(struct sk_buff *skb, int ret)
> {
> - struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;
> + struct ovpn_crypto_key_slot *ks = ovpn_skb_cb(skb)->ctx->ks;
> + struct ovpn_peer *peer = ovpn_skb_cb(skb)->ctx->peer;
ovpn_skb_cb(skb)->ctx may not have been set by ovpn_aead_encrypt.
> +
> + /* encryption is happening asynchronously. This function will be
> + * called later by the crypto callback with a proper return value
> + */
> + if (unlikely(ret == -EINPROGRESS))
> + return;
>
> if (unlikely(ret < 0))
> goto err;
>
> skb_mark_not_on_list(skb);
>
> + kfree(ovpn_skb_cb(skb)->ctx);
> +
> switch (peer->sock->sock->sk->sk_protocol) {
> case IPPROTO_UDP:
> ovpn_udp_send_skb(peer->ovpn, peer, skb);
> break;
> default:
> /* no transport configured yet */
> goto err;
ovpn_skb_cb(skb)->ctx has just been freed before this switch, and here
we jump to err and free it again.
> }
> /* skb passed down the stack - don't free it */
> skb = NULL;
> err:
> if (unlikely(skb)) {
> dev_core_stats_tx_dropped_inc(peer->ovpn->dev);
> - kfree_skb(skb);
> + kfree(ovpn_skb_cb(skb)->ctx);
> }
> + kfree_skb(skb);
> + ovpn_crypto_key_slot_put(ks);
> ovpn_peer_put(peer);
> }
--
Sabrina
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 12/25] ovpn: implement packet processing
2024-09-02 14:42 ` Sabrina Dubroca
@ 2024-09-04 12:07 ` Antonio Quartulli
2024-09-04 15:01 ` Sabrina Dubroca
0 siblings, 1 reply; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-04 12:07 UTC (permalink / raw)
To: Sabrina Dubroca; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
Hi,
On 02/09/2024 16:42, Sabrina Dubroca wrote:
> 2024-08-27, 14:07:52 +0200, Antonio Quartulli wrote:
>> +/* this swap is not atomic, but there will be a very short time frame where the
>
> Since we're under a mutex, I think we might get put to sleep for a
> not-so-short time frame.
>
>> + * old_secondary key won't be available. This should not be a big deal as most
>
> I could be misreading the code, but isn't it old_primary that's
> unavailable during the swap? rcu_replace_pointer overwrites
> cs->primary, so before the final assign, both slots contain
> old_secondary?
Right. The comment is not correct.
cs->secondary (old_secondary, that is the newest key) is what is
probably being used by the other peer for sending traffic.
Therefore old_secondary is what is likely to be needed.
However, this is pure speculation and may not be accurate.
The fact that we could sleep before having completed the swap sounds
like something we want to avoid.
Maybe I should convert this mutex to a spinlock. Its usage is fairly
contained anyway.
>
>> + * 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;
>> +
>> + mutex_lock(&cs->mutex);
>> +
>> + old_secondary = rcu_dereference_protected(cs->secondary,
>> + lockdep_is_held(&cs->mutex));
>> + old_primary = rcu_replace_pointer(cs->primary, old_secondary,
>> + lockdep_is_held(&cs->mutex));
>> + rcu_assign_pointer(cs->secondary, old_primary);
>> +
>> + pr_debug("key swapped: %u <-> %u\n",
>> + old_primary ? old_primary->key_id : 0,
>> + old_secondary ? old_secondary->key_id : 0);
>> +
>> + mutex_unlock(&cs->mutex);
>> +}
>
> [...]
>> +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);
>> + const unsigned int head_size = ovpn_aead_encap_overhead(ks);
>> + DECLARE_CRYPTO_WAIT(wait);
>
> nit: unused
ACK
>
>> + struct aead_request *req;
>> + struct sk_buff *trailer;
>> + struct scatterlist *sg;
>> + u8 iv[NONCE_SIZE];
>> + int nfrags, ret;
>> + u32 pktid, op;
>> +
>> + /* 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, after adding network header and encryption overhead
>> + */
>> + if (unlikely(skb_cow_head(skb, OVPN_HEAD_ROOM + head_size)))
>> + 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;
>> +
>> + ovpn_skb_cb(skb)->ctx = kmalloc(sizeof(*ovpn_skb_cb(skb)->ctx),
>> + GFP_ATOMIC);
>> + if (unlikely(!ovpn_skb_cb(skb)->ctx))
>> + return -ENOMEM;
>
> I think you should clear skb->cb (or at least ->ctx) at the start of
> ovpn_aead_encrypt. I don't think it will be cleaned up by the previous
> user, and if we fail before this alloc, we will possibly have bogus
> values in ->ctx when we get to kfree(ovpn_skb_cb(skb)->ctx) at the end
> of ovpn_encrypt_post.
>
> (Similar comments around cb/ctx freeing and initialization apply to
> ovpn_aead_decrypt and ovpn_decrypt_post)
good point - will clear it in both cases.
>
>> + sg = ovpn_skb_cb(skb)->ctx->sg;
>> +
>> + /* sg table:
>> + * 0: op, wire nonce (AD, len=OVPN_OP_SIZE_V2+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)) {
>> + kfree(sg);
>
> This is the only location in this function (and ovpn_encrypt_post)
> that frees sg. Is that correct? sg points to an array contained within
> ->ctx, I don't think you want to free that directly.
No, it is not correct. As you pointed out 'sg' is an actual array so
should not be free'd.
This is a leftover of the first version where 'sg' was kmalloc'd.
FTR: this restructuring is the result of having tested
encryption/decryption with pcrypt: sg, that is passed to the crypto
code, was initially allocated on the stack, which was obviously not
working for async crypto.
The solution was to make it part of the skb CB area, so that it can be
carried around until crypto is done.
>
>> + return -EINVAL;
>> + }
>> +
>> + /* 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)) {
>> + kfree(ovpn_skb_cb(skb)->ctx);
>
> Isn't that going to cause a double-free when we get to the end of
> ovpn_encrypt_post? Or even UAF when we try to get ks/peer at the
> start?
ouch. you're right.
I should better leave it alone and let ovpn_encrypt_post take care of
free'ing it at the end.
>
>> + return ret;
>> + }
>> +
>> + /* 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, NONCE_WIRE_SIZE);
>> + memcpy(skb->data, iv, 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_OP_SIZE_V2);
>> + BUILD_BUG_ON(sizeof(op) != OVPN_OP_SIZE_V2);
>> + *((__force __be32 *)skb->data) = htonl(op);
>> +
>> + /* AEAD Additional data */
>> + sg_set_buf(sg, skb->data, OVPN_OP_SIZE_V2 + NONCE_WIRE_SIZE);
>> +
>> + req = aead_request_alloc(ks->encrypt, GFP_ATOMIC);
>> + if (unlikely(!req)) {
>> + kfree(ovpn_skb_cb(skb)->ctx);
>
> Same here.
yap
>
>> + return -ENOMEM;
>> + }
>> +
>> + /* setup async crypto operation */
>> + aead_request_set_tfm(req, ks->encrypt);
>> + aead_request_set_callback(req, 0, ovpn_aead_encrypt_done, skb);
>> + aead_request_set_crypt(req, sg, sg, skb->len - head_size, iv);
>> + aead_request_set_ad(req, OVPN_OP_SIZE_V2 + NONCE_WIRE_SIZE);
>> +
>> + ovpn_skb_cb(skb)->ctx->peer = peer;
>> + ovpn_skb_cb(skb)->ctx->req = req;
>> + ovpn_skb_cb(skb)->ctx->ks = ks;
>> +
>> + /* encrypt it */
>> + return crypto_aead_encrypt(req);
>> +}
>> +
>> +static void ovpn_aead_decrypt_done(void *data, int ret)
>> +{
>> + struct sk_buff *skb = data;
>> +
>> + aead_request_free(ovpn_skb_cb(skb)->ctx->req);
>
> This function only gets called in the async case. Where's the
> corresponding aead_request_free in the sync case? (same for encrypt)
> This should be moved into ovpn_decrypt_post, I think.
I agree, although I am pretty sure I moved it here in the past for a reason.
Maybe code changes eliminated that reason.
anyway, thanks for spotting this. I'll definitely move it to the _post
functions.
>
>> + ovpn_decrypt_post(skb, 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;
>> + DECLARE_CRYPTO_WAIT(wait);
>
> nit: unused
ACK
>
>
> [...]
>> -static void ovpn_encrypt_post(struct sk_buff *skb, int ret)
>> +void ovpn_encrypt_post(struct sk_buff *skb, int ret)
>> {
>> - struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;
>> + struct ovpn_crypto_key_slot *ks = ovpn_skb_cb(skb)->ctx->ks;
>> + struct ovpn_peer *peer = ovpn_skb_cb(skb)->ctx->peer;
>
> ovpn_skb_cb(skb)->ctx may not have been set by ovpn_aead_encrypt.
right. we may have hit a return before kmalloc'ing it.
>
>> +
>> + /* encryption is happening asynchronously. This function will be
>> + * called later by the crypto callback with a proper return value
>> + */
>> + if (unlikely(ret == -EINPROGRESS))
>> + return;
>>
>> if (unlikely(ret < 0))
>> goto err;
>>
>> skb_mark_not_on_list(skb);
>>
>> + kfree(ovpn_skb_cb(skb)->ctx);
>> +
>> switch (peer->sock->sock->sk->sk_protocol) {
>> case IPPROTO_UDP:
>> ovpn_udp_send_skb(peer->ovpn, peer, skb);
>> break;
>> default:
>> /* no transport configured yet */
>> goto err;
>
> ovpn_skb_cb(skb)->ctx has just been freed before this switch, and here
> we jump to err and free it again.
Thanks. Will reworka bit the error path here.
>
>> }
>> /* skb passed down the stack - don't free it */
>> skb = NULL;
>> err:
>> if (unlikely(skb)) {
>> dev_core_stats_tx_dropped_inc(peer->ovpn->dev);
>> - kfree_skb(skb);
>> + kfree(ovpn_skb_cb(skb)->ctx);
>> }
>> + kfree_skb(skb);
>> + ovpn_crypto_key_slot_put(ks);
>> ovpn_peer_put(peer);
>> }
>
This patch was basically re-written after realizing that the async
crypto path was not working as expected, therefore sorry if there were
some "kinda obvious" mistakes.
Thanks a lot for your review.
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 12/25] ovpn: implement packet processing
2024-09-04 12:07 ` Antonio Quartulli
@ 2024-09-04 15:01 ` Sabrina Dubroca
2024-09-06 13:19 ` Antonio Quartulli
0 siblings, 1 reply; 58+ messages in thread
From: Sabrina Dubroca @ 2024-09-04 15:01 UTC (permalink / raw)
To: Antonio Quartulli; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
2024-09-04, 14:07:23 +0200, Antonio Quartulli wrote:
> Hi,
>
> On 02/09/2024 16:42, Sabrina Dubroca wrote:
> > 2024-08-27, 14:07:52 +0200, Antonio Quartulli wrote:
> > > +/* this swap is not atomic, but there will be a very short time frame where the
> >
> > Since we're under a mutex, I think we might get put to sleep for a
> > not-so-short time frame.
> >
> > > + * old_secondary key won't be available. This should not be a big deal as most
> >
> > I could be misreading the code, but isn't it old_primary that's
> > unavailable during the swap? rcu_replace_pointer overwrites
> > cs->primary, so before the final assign, both slots contain
> > old_secondary?
>
> Right. The comment is not correct.
>
> cs->secondary (old_secondary, that is the newest key) is what is probably
> being used by the other peer for sending traffic.
Right, thanks. I was getting confused about the key slots and which
key was the newest.
If the peer has already started sending with the newest key, no
problem. If we're swapping keys before our peer (or we're on a slow
network and the peer's packets get delayed), we'll still be receiving
packets encrypted with the old key.
> Therefore old_secondary is what is likely to be needed.
>
> However, this is pure speculation and may not be accurate.
I can think of a few possibilities if this causes too many unwanted
drops:
- use a linked list of keys, set the primary instead of swapping, and
let delete remove the unused key(s) by ID instead of slot
- decouple the TX and RX keys, which also means you don't really need
to swap keys (swap for the TX key becomes "set primary", swap on RX
can become a noop since you check both slots for the correct keyid)
-- and here too delete becomes based on key ID
- if cs->mutex becomes a spinlock, take it in the datapath when
looking up keys. this will make sure we get a consistent view of
the keys state.
- come up with a scheme to let the datapath retry the key lookup if
it didn't find the key it wanted (maybe something like a seqcount,
or maybe taking the lock and retrying if the lookup failed)
I don't know if options 1 and 2 are possible based on how openvpn (the
protocol and the userspace application) models keys, but they seem a
bit "cleaner" on the datapath side (no locking, no retry). But they
require a different API.
Do you have the same problem in the current userspace implementation?
> The fact that we could sleep before having completed the swap sounds like
> something we want to avoid.
> Maybe I should convert this mutex to a spinlock. Its usage is fairly
> contained anyway.
I think it would make sense. It's only being held for very short
periods, just to set/swap a few pointers.
> FTR: this restructuring is the result of having tested encryption/decryption
> with pcrypt: sg, that is passed to the crypto code, was initially allocated
> on the stack, which was obviously not working for async crypto.
> The solution was to make it part of the skb CB area, so that it can be
> carried around until crypto is done.
I see. I thought this patch looked less familiar than the others :)
An alternative to using the CB is what IPsec does: allocate a chunk of
memory for all its temporary needs (crypto req, sg, iv, anything else
it needs during async crypto) and carve the pointers/small chunks out
of it. See esp_alloc_tmp in net/ipv4/esp4.c. (I'm just mentioning
that for reference/curiosity, not asking that you change ovpn)
> This patch was basically re-written after realizing that the async crypto
> path was not working as expected, therefore sorry if there were some "kinda
> obvious" mistakes.
And I completely missed some of those issues in previous reviews.
> Thanks a lot for your review.
Cheers, and thanks for your patience.
--
Sabrina
^ permalink raw reply [flat|nested] 58+ messages in thread
* Re: [PATCH net-next v6 12/25] ovpn: implement packet processing
2024-09-04 15:01 ` Sabrina Dubroca
@ 2024-09-06 13:19 ` Antonio Quartulli
2024-09-10 13:04 ` Sabrina Dubroca
0 siblings, 1 reply; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-06 13:19 UTC (permalink / raw)
To: Sabrina Dubroca; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
On 04/09/2024 17:01, Sabrina Dubroca wrote:
> 2024-09-04, 14:07:23 +0200, Antonio Quartulli wrote:
>> Hi,
>>
>> On 02/09/2024 16:42, Sabrina Dubroca wrote:
>>> 2024-08-27, 14:07:52 +0200, Antonio Quartulli wrote:
>>>> +/* this swap is not atomic, but there will be a very short time frame where the
>>>
>>> Since we're under a mutex, I think we might get put to sleep for a
>>> not-so-short time frame.
>>>
>>>> + * old_secondary key won't be available. This should not be a big deal as most
>>>
>>> I could be misreading the code, but isn't it old_primary that's
>>> unavailable during the swap? rcu_replace_pointer overwrites
>>> cs->primary, so before the final assign, both slots contain
>>> old_secondary?
>>
>> Right. The comment is not correct.
>>
>> cs->secondary (old_secondary, that is the newest key) is what is probably
>> being used by the other peer for sending traffic.
>
> Right, thanks. I was getting confused about the key slots and which
> key was the newest.
>
> If the peer has already started sending with the newest key, no
> problem. If we're swapping keys before our peer (or we're on a slow
> network and the peer's packets get delayed), we'll still be receiving
> packets encrypted with the old key.
Right, it's mostly impossible to make the swap happen at the same time
on both ends.
>
>
>> Therefore old_secondary is what is likely to be needed.
>>
>> However, this is pure speculation and may not be accurate.
>
> I can think of a few possibilities if this causes too many unwanted
> drops:
>
> - use a linked list of keys, set the primary instead of swapping, and
> let delete remove the unused key(s) by ID instead of slot
>
> - decouple the TX and RX keys, which also means you don't really need
> to swap keys (swap for the TX key becomes "set primary", swap on RX
> can become a noop since you check both slots for the correct keyid)
> -- and here too delete becomes based on key ID
>
> - if cs->mutex becomes a spinlock, take it in the datapath when
> looking up keys. this will make sure we get a consistent view of
> the keys state.
>
> - come up with a scheme to let the datapath retry the key lookup if
> it didn't find the key it wanted (maybe something like a seqcount,
> or maybe taking the lock and retrying if the lookup failed)
>
> I don't know if options 1 and 2 are possible based on how openvpn (the
> protocol and the userspace application) models keys, but they seem a
> bit "cleaner" on the datapath side (no locking, no retry). But they
> require a different API.
After chewing over all these ideas I think we can summarize the
requirements as follows:
* PRIMARY and SECONDARY in the API is just an abstraction for "KEY FOR
TX" and "THE OTHER KEY";
* SWAP means "mark for TX the key that currently was not marked";
* we only need a pointer to the key for TX;
* key for RX is picked up by key ID;
Therefore, how about having an array large enough to store all key IDs
(max ID is 7):
* array index is the key ID (fast lookup on RX);
* upon SET_KEY we store the provided keys and erase the rest;
* upon SET_KEY we store in a new field the index/ID of the PRIMARY (fast
lookup on TX), namely primary_id;
* upon SWAP we just save in primary_id the "other" index/ID;
* at any given time we will have only two keys in the array.
It's pretty much like your option 1 and 2, but using an array indexed by
key ID.
The concept of slot is a bit lost, but it is not important as long as we
can keep the API and its semantics the same.
Opinions?
>
> Do you have the same problem in the current userspace implementation?
userspace is single-threaded :-P
nothing happens while we are busy swapping.
>
>
>> The fact that we could sleep before having completed the swap sounds like
>> something we want to avoid.
>> Maybe I should convert this mutex to a spinlock. Its usage is fairly
>> contained anyway.
>
> I think it would make sense. It's only being held for very short
> periods, just to set/swap a few pointers.
ACK
>
>
>> FTR: this restructuring is the result of having tested encryption/decryption
>> with pcrypt: sg, that is passed to the crypto code, was initially allocated
>> on the stack, which was obviously not working for async crypto.
>> The solution was to make it part of the skb CB area, so that it can be
>> carried around until crypto is done.
>
> I see. I thought this patch looked less familiar than the others :)
>
> An alternative to using the CB is what IPsec does: allocate a chunk of
> memory for all its temporary needs (crypto req, sg, iv, anything else
> it needs during async crypto) and carve the pointers/small chunks out
> of it. See esp_alloc_tmp in net/ipv4/esp4.c. (I'm just mentioning
> that for reference/curiosity, not asking that you change ovpn)
>
>
>> This patch was basically re-written after realizing that the async crypto
>> path was not working as expected, therefore sorry if there were some "kinda
>> obvious" mistakes.
>
> And I completely missed some of those issues in previous reviews.
>
>> Thanks a lot for your review.
>
> Cheers, and thanks for your patience.
>
Cheers!
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread
* Re: [PATCH net-next v6 12/25] ovpn: implement packet processing
2024-09-06 13:19 ` Antonio Quartulli
@ 2024-09-10 13:04 ` Sabrina Dubroca
2024-09-11 12:52 ` Antonio Quartulli
0 siblings, 1 reply; 58+ messages in thread
From: Sabrina Dubroca @ 2024-09-10 13:04 UTC (permalink / raw)
To: Antonio Quartulli; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
2024-09-06, 15:19:08 +0200, Antonio Quartulli wrote:
> On 04/09/2024 17:01, Sabrina Dubroca wrote:
> > 2024-09-04, 14:07:23 +0200, Antonio Quartulli wrote:
> > > On 02/09/2024 16:42, Sabrina Dubroca wrote:
> > > > 2024-08-27, 14:07:52 +0200, Antonio Quartulli wrote:
> > I can think of a few possibilities if this causes too many unwanted
> > drops:
> >
> > - use a linked list of keys, set the primary instead of swapping, and
> > let delete remove the unused key(s) by ID instead of slot
> >
> > - decouple the TX and RX keys, which also means you don't really need
> > to swap keys (swap for the TX key becomes "set primary", swap on RX
> > can become a noop since you check both slots for the correct keyid)
> > -- and here too delete becomes based on key ID
> >
> > - if cs->mutex becomes a spinlock, take it in the datapath when
> > looking up keys. this will make sure we get a consistent view of
> > the keys state.
> >
> > - come up with a scheme to let the datapath retry the key lookup if
> > it didn't find the key it wanted (maybe something like a seqcount,
> > or maybe taking the lock and retrying if the lookup failed)
> >
> > I don't know if options 1 and 2 are possible based on how openvpn (the
> > protocol and the userspace application) models keys, but they seem a
> > bit "cleaner" on the datapath side (no locking, no retry). But they
> > require a different API.
>
> After chewing over all these ideas I think we can summarize the requirements
> as follows:
>
> * PRIMARY and SECONDARY in the API is just an abstraction for "KEY FOR TX"
> and "THE OTHER KEY";
> * SWAP means "mark for TX the key that currently was not marked";
> * we only need a pointer to the key for TX;
> * key for RX is picked up by key ID;
>
> Therefore, how about having an array large enough to store all key IDs (max
> ID is 7):
Right, I forgot about that. For 8 keys, sure, array sounds ok. MACsec
has only 4 and I also implemented it as an array
(include/net/macsec.h: macsec_{tx,rx}_sc, sa array).
> * array index is the key ID (fast lookup on RX);
> * upon SET_KEY we store the provided keys and erase the rest;
I'm not sure about erasing the rest. If you're installing the
secondary ("next primary") key, you can't just erase the current
primary? ("erase the rest" also means you'd only ever have one key in
the array, which contradicts your last item in this list)
> * upon SET_KEY we store in a new field the index/ID of the PRIMARY (fast
> lookup on TX), namely primary_id;
> * upon SWAP we just save in primary_id the "other" index/ID;
I'm confused by these two. Both SET_KEY and SWAP modify the primary_id?
> * at any given time we will have only two keys in the array.
This needs to be enforced in the SET_KEY implementation, otherwise
SWAP will have inconsistent effects.
> It's pretty much like your option 1 and 2, but using an array
> indexed by key ID.
Are you decoupling TX and RX keys (so that they can be installed
independently) in this proposal? I can't really tell, the array could
be key pairs or separate.
> The concept of slot is a bit lost, but it is not important as long as we can
> keep the API and its semantics the same.
Would it be a problem for userspace to keep track of key IDs, and use
that (instead of slots) to communicate with the kernel? Make
setkey/delkey be based on keyid, and replace swap with a set_tx
operation which updates the current keyid for TX. That would seem like
a better API, especially for the per-ID array you're proposing
here. The concept of slots would be almost completely lost (only
"current tx key" is left, which is similar to the "primary slot").
(it becomes almost identical to the way MACsec does things, except
possibly that in MACsec the TX and RX keys are not paired at all, so
you can install/delete a TX key without touching any RX key)
Maybe you can also rework the current code to look a bit like this
array-based proposal, and not give up the notion of slots, if that's
something strongly built into the core of openvpn:
- primary/secondary in ovpn_crypto_state become slots[2]
- add a one-bit "primary" reference, used to look into the slots array
- swap just flips that "primary" bit
- TX uses slots[primary]
- RX keeps inspecting both slots (now slot[0] and slot[1] instead of
primary/secondary) looking for the correct keyid
- setkey/delkey still operate on primary/secondary, but need to figure
out whether slot[0] or slot[1] is primary/secondary based on
->primary
It's almost identical to the current code (and API), except you don't
need to reassign any pointers to swap keys, so it should avoid the
rekey issue.
--
Sabrina
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 12/25] ovpn: implement packet processing
2024-09-10 13:04 ` Sabrina Dubroca
@ 2024-09-11 12:52 ` Antonio Quartulli
2024-09-11 13:30 ` Sabrina Dubroca
0 siblings, 1 reply; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-11 12:52 UTC (permalink / raw)
To: Sabrina Dubroca; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
On 10/09/2024 15:04, Sabrina Dubroca wrote:
> 2024-09-06, 15:19:08 +0200, Antonio Quartulli wrote:
>> On 04/09/2024 17:01, Sabrina Dubroca wrote:
>>> 2024-09-04, 14:07:23 +0200, Antonio Quartulli wrote:
>>>> On 02/09/2024 16:42, Sabrina Dubroca wrote:
>>>>> 2024-08-27, 14:07:52 +0200, Antonio Quartulli wrote:
>>> I can think of a few possibilities if this causes too many unwanted
>>> drops:
>>>
>>> - use a linked list of keys, set the primary instead of swapping, and
>>> let delete remove the unused key(s) by ID instead of slot
>>>
>>> - decouple the TX and RX keys, which also means you don't really need
>>> to swap keys (swap for the TX key becomes "set primary", swap on RX
>>> can become a noop since you check both slots for the correct keyid)
>>> -- and here too delete becomes based on key ID
>>>
>>> - if cs->mutex becomes a spinlock, take it in the datapath when
>>> looking up keys. this will make sure we get a consistent view of
>>> the keys state.
>>>
>>> - come up with a scheme to let the datapath retry the key lookup if
>>> it didn't find the key it wanted (maybe something like a seqcount,
>>> or maybe taking the lock and retrying if the lookup failed)
>>>
>>> I don't know if options 1 and 2 are possible based on how openvpn (the
>>> protocol and the userspace application) models keys, but they seem a
>>> bit "cleaner" on the datapath side (no locking, no retry). But they
>>> require a different API.
>>
>> After chewing over all these ideas I think we can summarize the requirements
>> as follows:
>>
>> * PRIMARY and SECONDARY in the API is just an abstraction for "KEY FOR TX"
>> and "THE OTHER KEY";
>> * SWAP means "mark for TX the key that currently was not marked";
>> * we only need a pointer to the key for TX;
>> * key for RX is picked up by key ID;
>>
>> Therefore, how about having an array large enough to store all key IDs (max
>> ID is 7):
>
> Right, I forgot about that. For 8 keys, sure, array sounds ok. MACsec
> has only 4 and I also implemented it as an array
> (include/net/macsec.h: macsec_{tx,rx}_sc, sa array).
thanks for the pointer!
>
>> * array index is the key ID (fast lookup on RX);
>> * upon SET_KEY we store the provided keys and erase the rest;
>
> I'm not sure about erasing the rest. If you're installing the
> secondary ("next primary") key, you can't just erase the current
> primary? ("erase the rest" also means you'd only ever have one key in
> the array, which contradicts your last item in this list)
Yeah, my point is wrong.
I fooled myself assuming SET_KEY would install two keys each time, but
this is not the case, so we can't "erase everything else".
What we can do is:
* if SET_KEY wants to install a key in PRIMARY, then we erase the key
marked as "primary" and we mark the new one as such
* if SET_KEY wants to install a key in SECONDARY, then we erase the key
without any mark.
This way we simulate writing into slots.
>
>> * upon SET_KEY we store in a new field the index/ID of the PRIMARY (fast
>> lookup on TX), namely primary_id;
FTR: this is what "marking as primary" means
>> * upon SWAP we just save in primary_id the "other" index/ID;
>
> I'm confused by these two. Both SET_KEY and SWAP modify the primary_id?
Yes.
SET_KEY may want to install a key in the primary slot: in that case the
new key has to be marked as primary immediately.
This normally happens only upon first SET_KEY after connection, when no
other key exists.
SWAP will switch primary_id to the other key ID.
makes sense?
>
>> * at any given time we will have only two keys in the array.
>
> This needs to be enforced in the SET_KEY implementation, otherwise
> SWAP will have inconsistent effects.
yap. I hope what I wrote above about SET_KEY helps clarifying this part.
>
>
>> It's pretty much like your option 1 and 2, but using an array
>> indexed by key ID.
>
> Are you decoupling TX and RX keys (so that they can be installed
> independently) in this proposal? I can't really tell, the array could
> be key pairs or separate.
I would not decouple TX and RX keys.
Each array item should be the same as what we are now storing into each
slot (struct ovpn_crypto_key_slot *).
I could use two arrays, instead of an array of slots, but that means
changing way more logic and I don't see the benefit.
>
>
>> The concept of slot is a bit lost, but it is not important as long as we can
>> keep the API and its semantics the same.
>
> Would it be a problem for userspace to keep track of key IDs, and use
> that (instead of slots) to communicate with the kernel? Make
> setkey/delkey be based on keyid, and replace swap with a set_tx
> operation which updates the current keyid for TX. That would seem like
> a better API, especially for the per-ID array you're proposing
> here. The concept of slots would be almost completely lost (only
> "current tx key" is left, which is similar to the "primary slot").
> (it becomes almost identical to the way MACsec does things, except
> possibly that in MACsec the TX and RX keys are not paired at all, so
> you can install/delete a TX key without touching any RX key)
>
unfortunately changing userspace that way is not currently viable.
There are more components (and documentation) that attach to this slot
abstraction.
Hence my proposal to keep the API the same, but rework the internal for
better implementation.
>
> Maybe you can also rework the current code to look a bit like this
> array-based proposal, and not give up the notion of slots, if that's
> something strongly built into the core of openvpn:
>
> - primary/secondary in ovpn_crypto_state become slots[2]
> - add a one-bit "primary" reference, used to look into the slots array
> - swap just flips that "primary" bit
> - TX uses slots[primary]
> - RX keeps inspecting both slots (now slot[0] and slot[1] instead of
> primary/secondary) looking for the correct keyid
> - setkey/delkey still operate on primary/secondary, but need to figure
> out whether slot[0] or slot[1] is primary/secondary based on
> ->primary
>
> It's almost identical to the current code (and API), except you don't
> need to reassign any pointers to swap keys, so it should avoid the
> rekey issue.
This approach sounds very close to what I was aiming for, but simpler
because we have slots[2] instead of slots[8] (which means that
primary_id can be just 'one-bit').
The only downside is that upon RX we have to check both keys.
However I don't think this is an issue as we have just 2 keys at most.
I could even optimize the lookup by starting always from the primary
key, as that's the one being used most of the time by the sender.
Ok, I will go with this approach you summarized here at the end.
Thanks a lot!
Cheers,
>
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 12/25] ovpn: implement packet processing
2024-09-11 12:52 ` Antonio Quartulli
@ 2024-09-11 13:30 ` Sabrina Dubroca
2024-09-12 8:33 ` Antonio Quartulli
0 siblings, 1 reply; 58+ messages in thread
From: Sabrina Dubroca @ 2024-09-11 13:30 UTC (permalink / raw)
To: Antonio Quartulli; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
2024-09-11, 14:52:10 +0200, Antonio Quartulli wrote:
> On 10/09/2024 15:04, Sabrina Dubroca wrote:
> > 2024-09-06, 15:19:08 +0200, Antonio Quartulli wrote:
> > > Therefore, how about having an array large enough to store all key IDs (max
> > > ID is 7):
> >
> > Right, I forgot about that. For 8 keys, sure, array sounds ok. MACsec
> > has only 4 and I also implemented it as an array
> > (include/net/macsec.h: macsec_{tx,rx}_sc, sa array).
>
> thanks for the pointer!
>
> >
> > > * array index is the key ID (fast lookup on RX);
> > > * upon SET_KEY we store the provided keys and erase the rest;
> >
> > I'm not sure about erasing the rest. If you're installing the
> > secondary ("next primary") key, you can't just erase the current
> > primary? ("erase the rest" also means you'd only ever have one key in
> > the array, which contradicts your last item in this list)
> Yeah, my point is wrong.
> I fooled myself assuming SET_KEY would install two keys each time, but this
> is not the case, so we can't "erase everything else".
>
> What we can do is:
> * if SET_KEY wants to install a key in PRIMARY, then we erase the key marked
> as "primary" and we mark the new one as such
> * if SET_KEY wants to install a key in SECONDARY, then we erase the key
> without any mark.
Ok, then the DEL_KEY op would not really be needed.
>
> This way we simulate writing into slots.
>
> >
> > > * upon SET_KEY we store in a new field the index/ID of the PRIMARY (fast
> > > lookup on TX), namely primary_id;
>
> FTR: this is what "marking as primary" means
>
> > > * upon SWAP we just save in primary_id the "other" index/ID;
> >
> > I'm confused by these two. Both SET_KEY and SWAP modify the primary_id?
>
> Yes.
> SET_KEY may want to install a key in the primary slot: in that case the new
> key has to be marked as primary immediately.
> This normally happens only upon first SET_KEY after connection, when no
> other key exists.
>
> SWAP will switch primary_id to the other key ID.
>
> makes sense?
Yes, thanks, that fixes up all my confusion around setting primary_id.
> > > * at any given time we will have only two keys in the array.
> >
> > This needs to be enforced in the SET_KEY implementation, otherwise
> > SWAP will have inconsistent effects.
>
> yap. I hope what I wrote above about SET_KEY helps clarifying this part.
>
> >
> >
> > > It's pretty much like your option 1 and 2, but using an array
> > > indexed by key ID.
> >
> > Are you decoupling TX and RX keys (so that they can be installed
> > independently) in this proposal? I can't really tell, the array could
> > be key pairs or separate.
>
> I would not decouple TX and RX keys.
> Each array item should be the same as what we are now storing into each slot
> (struct ovpn_crypto_key_slot *).
> I could use two arrays, instead of an array of slots, but that means
> changing way more logic and I don't see the benefit.
Avoid changing both keys every time when a link has very asymmetric
traffic. And the concept of a primary/secondary key makes no sense on
receive, all you need is keyids, and there's no need to swap slots,
which avoids the "key not available during SWAP" issue
entirely. Primary key only makes sense on TX.
But I'm guessing the keypair concept is also baked deep into openvpn.
> > > The concept of slot is a bit lost, but it is not important as long as we can
> > > keep the API and its semantics the same.
> >
> > Would it be a problem for userspace to keep track of key IDs, and use
> > that (instead of slots) to communicate with the kernel? Make
> > setkey/delkey be based on keyid, and replace swap with a set_tx
> > operation which updates the current keyid for TX. That would seem like
> > a better API, especially for the per-ID array you're proposing
> > here. The concept of slots would be almost completely lost (only
> > "current tx key" is left, which is similar to the "primary slot").
> > (it becomes almost identical to the way MACsec does things, except
> > possibly that in MACsec the TX and RX keys are not paired at all, so
> > you can install/delete a TX key without touching any RX key)
> >
>
> unfortunately changing userspace that way is not currently viable.
> There are more components (and documentation) that attach to this slot
> abstraction.
I thought that might be the case. Too bad, it means we have to keep
the slots API and the kernel will be stuck with it forever (even if
some day userspace can manage key ids instead of slots).
> Hence my proposal to keep the API the same, but rework the internal for
> better implementation.
Yeah, that makes sense if you have that constraint imposed by the
existing userspace.
>
> >
> > Maybe you can also rework the current code to look a bit like this
> > array-based proposal, and not give up the notion of slots, if that's
> > something strongly built into the core of openvpn:
> >
> > - primary/secondary in ovpn_crypto_state become slots[2]
> > - add a one-bit "primary" reference, used to look into the slots array
> > - swap just flips that "primary" bit
> > - TX uses slots[primary]
> > - RX keeps inspecting both slots (now slot[0] and slot[1] instead of
> > primary/secondary) looking for the correct keyid
> > - setkey/delkey still operate on primary/secondary, but need to figure
> > out whether slot[0] or slot[1] is primary/secondary based on
> > ->primary
> >
> > It's almost identical to the current code (and API), except you don't
> > need to reassign any pointers to swap keys, so it should avoid the
> > rekey issue.
>
> This approach sounds very close to what I was aiming for, but simpler
> because we have slots[2] instead of slots[8] (which means that primary_id
> can be just 'one-bit').
Yes.
> The only downside is that upon RX we have to check both keys.
> However I don't think this is an issue as we have just 2 keys at most.
>
> I could even optimize the lookup by starting always from the primary key, as
> that's the one being used most of the time by the sender.
Nice.
> Ok, I will go with this approach you summarized here at the end.
Ok. I think it should be a pretty minimal set of changes on top of the
existing code, especially if you hide the primary/secondary accesses
in inline helpers.
--
Sabrina
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 12/25] ovpn: implement packet processing
2024-09-11 13:30 ` Sabrina Dubroca
@ 2024-09-12 8:33 ` Antonio Quartulli
2024-09-22 19:51 ` Sergey Ryazanov
0 siblings, 1 reply; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-12 8:33 UTC (permalink / raw)
To: Sabrina Dubroca; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
On 11/09/2024 15:30, Sabrina Dubroca wrote:
> 2024-09-11, 14:52:10 +0200, Antonio Quartulli wrote:
>> On 10/09/2024 15:04, Sabrina Dubroca wrote:
>>> 2024-09-06, 15:19:08 +0200, Antonio Quartulli wrote:
>>>> Therefore, how about having an array large enough to store all key IDs (max
>>>> ID is 7):
>>>
>>> Right, I forgot about that. For 8 keys, sure, array sounds ok. MACsec
>>> has only 4 and I also implemented it as an array
>>> (include/net/macsec.h: macsec_{tx,rx}_sc, sa array).
>>
>> thanks for the pointer!
>>
>>>
>>>> * array index is the key ID (fast lookup on RX);
>>>> * upon SET_KEY we store the provided keys and erase the rest;
>>>
>>> I'm not sure about erasing the rest. If you're installing the
>>> secondary ("next primary") key, you can't just erase the current
>>> primary? ("erase the rest" also means you'd only ever have one key in
>>> the array, which contradicts your last item in this list)
>> Yeah, my point is wrong.
>> I fooled myself assuming SET_KEY would install two keys each time, but this
>> is not the case, so we can't "erase everything else".
>>
>> What we can do is:
>> * if SET_KEY wants to install a key in PRIMARY, then we erase the key marked
>> as "primary" and we mark the new one as such
>> * if SET_KEY wants to install a key in SECONDARY, then we erase the key
>> without any mark.
>
> Ok, then the DEL_KEY op would not really be needed.
It would be needed only when we want to kick an old key without
installing a new one.
IMHO something that should not truly happen during the normal lifecycle
of a peer, but there might be some corner cases where userspace may
still want to do that (I am checking userspace to understand when this
can truly happen, if at all)
>
>>
>> This way we simulate writing into slots.
>>
>>>
>>>> * upon SET_KEY we store in a new field the index/ID of the PRIMARY (fast
>>>> lookup on TX), namely primary_id;
>>
>> FTR: this is what "marking as primary" means
>>
>>>> * upon SWAP we just save in primary_id the "other" index/ID;
>>>
>>> I'm confused by these two. Both SET_KEY and SWAP modify the primary_id?
>>
>> Yes.
>> SET_KEY may want to install a key in the primary slot: in that case the new
>> key has to be marked as primary immediately.
>> This normally happens only upon first SET_KEY after connection, when no
>> other key exists.
>>
>> SWAP will switch primary_id to the other key ID.
>>
>> makes sense?
>
> Yes, thanks, that fixes up all my confusion around setting primary_id.
>
>>>> * at any given time we will have only two keys in the array.
>>>
>>> This needs to be enforced in the SET_KEY implementation, otherwise
>>> SWAP will have inconsistent effects.
>>
>> yap. I hope what I wrote above about SET_KEY helps clarifying this part.
>>
>>>
>>>
>>>> It's pretty much like your option 1 and 2, but using an array
>>>> indexed by key ID.
>>>
>>> Are you decoupling TX and RX keys (so that they can be installed
>>> independently) in this proposal? I can't really tell, the array could
>>> be key pairs or separate.
>>
>> I would not decouple TX and RX keys.
>> Each array item should be the same as what we are now storing into each slot
>> (struct ovpn_crypto_key_slot *).
>> I could use two arrays, instead of an array of slots, but that means
>> changing way more logic and I don't see the benefit.
>
> Avoid changing both keys every time when a link has very asymmetric
> traffic. And the concept of a primary/secondary key makes no sense on
> receive, all you need is keyids, and there's no need to swap slots,
> which avoids the "key not available during SWAP" issue
> entirely. Primary key only makes sense on TX.
>
> But I'm guessing the keypair concept is also baked deep into openvpn.
Correct. Both keys are recomputed upon each renegotiation, even if one
key was still usable.
>
>
>>>> The concept of slot is a bit lost, but it is not important as long as we can
>>>> keep the API and its semantics the same.
>>>
>>> Would it be a problem for userspace to keep track of key IDs, and use
>>> that (instead of slots) to communicate with the kernel? Make
>>> setkey/delkey be based on keyid, and replace swap with a set_tx
>>> operation which updates the current keyid for TX. That would seem like
>>> a better API, especially for the per-ID array you're proposing
>>> here. The concept of slots would be almost completely lost (only
>>> "current tx key" is left, which is similar to the "primary slot").
>>> (it becomes almost identical to the way MACsec does things, except
>>> possibly that in MACsec the TX and RX keys are not paired at all, so
>>> you can install/delete a TX key without touching any RX key)
>>>
>>
>> unfortunately changing userspace that way is not currently viable.
>> There are more components (and documentation) that attach to this slot
>> abstraction.
>
> I thought that might be the case. Too bad, it means we have to keep
> the slots API and the kernel will be stuck with it forever (even if
> some day userspace can manage key ids instead of slots).
Yap, but I think there won't be any change like that in the near future.
>
>> Hence my proposal to keep the API the same, but rework the internal for
>> better implementation.
>
> Yeah, that makes sense if you have that constraint imposed by the
> existing userspace.
>
>>
>>>
>>> Maybe you can also rework the current code to look a bit like this
>>> array-based proposal, and not give up the notion of slots, if that's
>>> something strongly built into the core of openvpn:
>>>
>>> - primary/secondary in ovpn_crypto_state become slots[2]
>>> - add a one-bit "primary" reference, used to look into the slots array
>>> - swap just flips that "primary" bit
>>> - TX uses slots[primary]
>>> - RX keeps inspecting both slots (now slot[0] and slot[1] instead of
>>> primary/secondary) looking for the correct keyid
>>> - setkey/delkey still operate on primary/secondary, but need to figure
>>> out whether slot[0] or slot[1] is primary/secondary based on
>>> ->primary
>>>
>>> It's almost identical to the current code (and API), except you don't
>>> need to reassign any pointers to swap keys, so it should avoid the
>>> rekey issue.
>>
>> This approach sounds very close to what I was aiming for, but simpler
>> because we have slots[2] instead of slots[8] (which means that primary_id
>> can be just 'one-bit').
>
> Yes.
>
>> The only downside is that upon RX we have to check both keys.
>> However I don't think this is an issue as we have just 2 keys at most.
>>
>> I could even optimize the lookup by starting always from the primary key, as
>> that's the one being used most of the time by the sender.
>
> Nice.
>
>> Ok, I will go with this approach you summarized here at the end.
>
> Ok. I think it should be a pretty minimal set of changes on top of the
> existing code, especially if you hide the primary/secondary accesses
> in inline helpers.
I think so to - working on it.
Thanks a lot!
Cheers,
>
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 12/25] ovpn: implement packet processing
2024-09-12 8:33 ` Antonio Quartulli
@ 2024-09-22 19:51 ` Sergey Ryazanov
2024-09-23 12:48 ` Antonio Quartulli
0 siblings, 1 reply; 58+ messages in thread
From: Sergey Ryazanov @ 2024-09-22 19:51 UTC (permalink / raw)
To: Antonio Quartulli, Sabrina Dubroca; +Cc: netdev, kuba, pabeni, edumazet, andrew
Hello Antonio, Sabrina,
let me join the key management design discussion and put my 2 cents in.
Please find my comment below.
On 12.09.2024 11:33, Antonio Quartulli wrote:
> On 11/09/2024 15:30, Sabrina Dubroca wrote:
>> 2024-09-11, 14:52:10 +0200, Antonio Quartulli wrote:
>>> On 10/09/2024 15:04, Sabrina Dubroca wrote:
>>>> 2024-09-06, 15:19:08 +0200, Antonio Quartulli wrote:
>>>>> Therefore, how about having an array large enough to store all key
>>>>> IDs (max
>>>>> ID is 7):
>>>>
>>>> Right, I forgot about that. For 8 keys, sure, array sounds ok. MACsec
>>>> has only 4 and I also implemented it as an array
>>>> (include/net/macsec.h: macsec_{tx,rx}_sc, sa array).
>>>
>>> thanks for the pointer!
>>>
>>>>
>>>>> * array index is the key ID (fast lookup on RX);
>>>>> * upon SET_KEY we store the provided keys and erase the rest;
>>>>
>>>> I'm not sure about erasing the rest. If you're installing the
>>>> secondary ("next primary") key, you can't just erase the current
>>>> primary? ("erase the rest" also means you'd only ever have one key in
>>>> the array, which contradicts your last item in this list)
>>> Yeah, my point is wrong.
>>> I fooled myself assuming SET_KEY would install two keys each time,
>>> but this
>>> is not the case, so we can't "erase everything else".
>>>
>>> What we can do is:
>>> * if SET_KEY wants to install a key in PRIMARY, then we erase the key
>>> marked
>>> as "primary" and we mark the new one as such
>>> * if SET_KEY wants to install a key in SECONDARY, then we erase the key
>>> without any mark.
>>
>> Ok, then the DEL_KEY op would not really be needed.
>
> It would be needed only when we want to kick an old key without
> installing a new one.
> IMHO something that should not truly happen during the normal lifecycle
> of a peer, but there might be some corner cases where userspace may
> still want to do that (I am checking userspace to understand when this
> can truly happen, if at all)
>
>>
>>>
>>> This way we simulate writing into slots.
>>>
>>>>
>>>>> * upon SET_KEY we store in a new field the index/ID of the PRIMARY
>>>>> (fast
>>>>> lookup on TX), namely primary_id;
>>>
>>> FTR: this is what "marking as primary" means
>>>
>>>>> * upon SWAP we just save in primary_id the "other" index/ID;
>>>>
>>>> I'm confused by these two. Both SET_KEY and SWAP modify the primary_id?
>>>
>>> Yes.
>>> SET_KEY may want to install a key in the primary slot: in that case
>>> the new
>>> key has to be marked as primary immediately.
>>> This normally happens only upon first SET_KEY after connection, when no
>>> other key exists.
>>>
>>> SWAP will switch primary_id to the other key ID.
>>>
>>> makes sense?
>>
>> Yes, thanks, that fixes up all my confusion around setting primary_id.
>>
>>>>> * at any given time we will have only two keys in the array.
>>>>
>>>> This needs to be enforced in the SET_KEY implementation, otherwise
>>>> SWAP will have inconsistent effects.
>>>
>>> yap. I hope what I wrote above about SET_KEY helps clarifying this part.
>>>
>>>>
>>>>
>>>>> It's pretty much like your option 1 and 2, but using an array
>>>>> indexed by key ID.
>>>>
>>>> Are you decoupling TX and RX keys (so that they can be installed
>>>> independently) in this proposal? I can't really tell, the array could
>>>> be key pairs or separate.
>>>
>>> I would not decouple TX and RX keys.
>>> Each array item should be the same as what we are now storing into
>>> each slot
>>> (struct ovpn_crypto_key_slot *).
>>> I could use two arrays, instead of an array of slots, but that means
>>> changing way more logic and I don't see the benefit.
>>
>> Avoid changing both keys every time when a link has very asymmetric
>> traffic. And the concept of a primary/secondary key makes no sense on
>> receive, all you need is keyids, and there's no need to swap slots,
>> which avoids the "key not available during SWAP" issue
>> entirely. Primary key only makes sense on TX.
>>
>> But I'm guessing the keypair concept is also baked deep into openvpn.
>
> Correct. Both keys are recomputed upon each renegotiation, even if one
> key was still usable.
>
>>
>>
>>>>> The concept of slot is a bit lost, but it is not important as long
>>>>> as we can
>>>>> keep the API and its semantics the same.
>>>>
>>>> Would it be a problem for userspace to keep track of key IDs, and use
>>>> that (instead of slots) to communicate with the kernel? Make
>>>> setkey/delkey be based on keyid, and replace swap with a set_tx
>>>> operation which updates the current keyid for TX. That would seem like
>>>> a better API, especially for the per-ID array you're proposing
>>>> here. The concept of slots would be almost completely lost (only
>>>> "current tx key" is left, which is similar to the "primary slot").
>>>> (it becomes almost identical to the way MACsec does things, except
>>>> possibly that in MACsec the TX and RX keys are not paired at all, so
>>>> you can install/delete a TX key without touching any RX key)
>>>>
>>>
>>> unfortunately changing userspace that way is not currently viable.
>>> There are more components (and documentation) that attach to this slot
>>> abstraction.
>>
>> I thought that might be the case. Too bad, it means we have to keep
>> the slots API and the kernel will be stuck with it forever (even if
>> some day userspace can manage key ids instead of slots).
>
> Yap, but I think there won't be any change like that in the near future.
As far as I understand the conclusion of the discussion, the best
practice for the keys management is to keep keys discrete including the
Tx/Rx keys separation. On the other hand, from the OpenVPN protocol
perspective, keys are grouped into slots and peers perform so called key
slots swapping.
As I can see, we have two options to adjust userspace application and
kernel to each other:
1) implement "key slots" abstraction in Netlink API to keep kernel
interface similar to the current OpenVPN protocol;
2) implement "discrete" keys management via Netlink API and move "slots"
abstraction to the userspace application.
Sabrina already mentioned that kernel will stuck with the slots
abstraction forever. This is due to the rule that user's API should not
be changed.
Antonio, can we consider implementing the slot abstraction in the
userspace application? It will move complexity from the kernel to the
userspace, where it can be easy debugged and maintained.
And since the keys management is part of the control plane. Keeping
abstraction closer to the control plane implementation will allow any
protocol modification, while keeping the kernel forward compatible.
>>> Hence my proposal to keep the API the same, but rework the internal for
>>> better implementation.
>>
>> Yeah, that makes sense if you have that constraint imposed by the
>> existing userspace.
>>
>>>
>>>>
>>>> Maybe you can also rework the current code to look a bit like this
>>>> array-based proposal, and not give up the notion of slots, if that's
>>>> something strongly built into the core of openvpn:
>>>>
>>>> - primary/secondary in ovpn_crypto_state become slots[2]
>>>> - add a one-bit "primary" reference, used to look into the slots array
>>>> - swap just flips that "primary" bit
>>>> - TX uses slots[primary]
>>>> - RX keeps inspecting both slots (now slot[0] and slot[1] instead of
>>>> primary/secondary) looking for the correct keyid
>>>> - setkey/delkey still operate on primary/secondary, but need to figure
>>>> out whether slot[0] or slot[1] is primary/secondary based on
>>>> ->primary
>>>>
>>>> It's almost identical to the current code (and API), except you don't
>>>> need to reassign any pointers to swap keys, so it should avoid the
>>>> rekey issue.
>>>
>>> This approach sounds very close to what I was aiming for, but simpler
>>> because we have slots[2] instead of slots[8] (which means that
>>> primary_id
>>> can be just 'one-bit').
>>
>> Yes.
>>
>>> The only downside is that upon RX we have to check both keys.
>>> However I don't think this is an issue as we have just 2 keys at most.
>>>
>>> I could even optimize the lookup by starting always from the primary
>>> key, as
>>> that's the one being used most of the time by the sender.
>>
>> Nice.
>>
>>> Ok, I will go with this approach you summarized here at the end.
>>
>> Ok. I think it should be a pretty minimal set of changes on top of the
>> existing code, especially if you hide the primary/secondary accesses
>> in inline helpers.
>
> I think so to - working on it.
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 12/25] ovpn: implement packet processing
2024-09-22 19:51 ` Sergey Ryazanov
@ 2024-09-23 12:48 ` Antonio Quartulli
0 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-23 12:48 UTC (permalink / raw)
To: Sergey Ryazanov, Sabrina Dubroca; +Cc: netdev, kuba, pabeni, edumazet, andrew
Hi,
On 22/09/2024 21:51, Sergey Ryazanov wrote:
> Hello Antonio, Sabrina,
>
> let me join the key management design discussion and put my 2 cents in.
> Please find my comment below.
>
> On 12.09.2024 11:33, Antonio Quartulli wrote:
>> On 11/09/2024 15:30, Sabrina Dubroca wrote:
>>> 2024-09-11, 14:52:10 +0200, Antonio Quartulli wrote:
>>>> On 10/09/2024 15:04, Sabrina Dubroca wrote:
>>>>> 2024-09-06, 15:19:08 +0200, Antonio Quartulli wrote:
>>>>>> Therefore, how about having an array large enough to store all key
>>>>>> IDs (max
>>>>>> ID is 7):
>>>>>
>>>>> Right, I forgot about that. For 8 keys, sure, array sounds ok. MACsec
>>>>> has only 4 and I also implemented it as an array
>>>>> (include/net/macsec.h: macsec_{tx,rx}_sc, sa array).
>>>>
>>>> thanks for the pointer!
>>>>
>>>>>
>>>>>> * array index is the key ID (fast lookup on RX);
>>>>>> * upon SET_KEY we store the provided keys and erase the rest;
>>>>>
>>>>> I'm not sure about erasing the rest. If you're installing the
>>>>> secondary ("next primary") key, you can't just erase the current
>>>>> primary? ("erase the rest" also means you'd only ever have one key in
>>>>> the array, which contradicts your last item in this list)
>>>> Yeah, my point is wrong.
>>>> I fooled myself assuming SET_KEY would install two keys each time,
>>>> but this
>>>> is not the case, so we can't "erase everything else".
>>>>
>>>> What we can do is:
>>>> * if SET_KEY wants to install a key in PRIMARY, then we erase the
>>>> key marked
>>>> as "primary" and we mark the new one as such
>>>> * if SET_KEY wants to install a key in SECONDARY, then we erase the key
>>>> without any mark.
>>>
>>> Ok, then the DEL_KEY op would not really be needed.
>>
>> It would be needed only when we want to kick an old key without
>> installing a new one.
>> IMHO something that should not truly happen during the normal
>> lifecycle of a peer, but there might be some corner cases where
>> userspace may still want to do that (I am checking userspace to
>> understand when this can truly happen, if at all)
>>
>>>
>>>>
>>>> This way we simulate writing into slots.
>>>>
>>>>>
>>>>>> * upon SET_KEY we store in a new field the index/ID of the PRIMARY
>>>>>> (fast
>>>>>> lookup on TX), namely primary_id;
>>>>
>>>> FTR: this is what "marking as primary" means
>>>>
>>>>>> * upon SWAP we just save in primary_id the "other" index/ID;
>>>>>
>>>>> I'm confused by these two. Both SET_KEY and SWAP modify the
>>>>> primary_id?
>>>>
>>>> Yes.
>>>> SET_KEY may want to install a key in the primary slot: in that case
>>>> the new
>>>> key has to be marked as primary immediately.
>>>> This normally happens only upon first SET_KEY after connection, when no
>>>> other key exists.
>>>>
>>>> SWAP will switch primary_id to the other key ID.
>>>>
>>>> makes sense?
>>>
>>> Yes, thanks, that fixes up all my confusion around setting primary_id.
>>>
>>>>>> * at any given time we will have only two keys in the array.
>>>>>
>>>>> This needs to be enforced in the SET_KEY implementation, otherwise
>>>>> SWAP will have inconsistent effects.
>>>>
>>>> yap. I hope what I wrote above about SET_KEY helps clarifying this
>>>> part.
>>>>
>>>>>
>>>>>
>>>>>> It's pretty much like your option 1 and 2, but using an array
>>>>>> indexed by key ID.
>>>>>
>>>>> Are you decoupling TX and RX keys (so that they can be installed
>>>>> independently) in this proposal? I can't really tell, the array could
>>>>> be key pairs or separate.
>>>>
>>>> I would not decouple TX and RX keys.
>>>> Each array item should be the same as what we are now storing into
>>>> each slot
>>>> (struct ovpn_crypto_key_slot *).
>>>> I could use two arrays, instead of an array of slots, but that means
>>>> changing way more logic and I don't see the benefit.
>>>
>>> Avoid changing both keys every time when a link has very asymmetric
>>> traffic. And the concept of a primary/secondary key makes no sense on
>>> receive, all you need is keyids, and there's no need to swap slots,
>>> which avoids the "key not available during SWAP" issue
>>> entirely. Primary key only makes sense on TX.
>>>
>>> But I'm guessing the keypair concept is also baked deep into openvpn.
>>
>> Correct. Both keys are recomputed upon each renegotiation, even if one
>> key was still usable.
>>
>>>
>>>
>>>>>> The concept of slot is a bit lost, but it is not important as long
>>>>>> as we can
>>>>>> keep the API and its semantics the same.
>>>>>
>>>>> Would it be a problem for userspace to keep track of key IDs, and use
>>>>> that (instead of slots) to communicate with the kernel? Make
>>>>> setkey/delkey be based on keyid, and replace swap with a set_tx
>>>>> operation which updates the current keyid for TX. That would seem like
>>>>> a better API, especially for the per-ID array you're proposing
>>>>> here. The concept of slots would be almost completely lost (only
>>>>> "current tx key" is left, which is similar to the "primary slot").
>>>>> (it becomes almost identical to the way MACsec does things, except
>>>>> possibly that in MACsec the TX and RX keys are not paired at all, so
>>>>> you can install/delete a TX key without touching any RX key)
>>>>>
>>>>
>>>> unfortunately changing userspace that way is not currently viable.
>>>> There are more components (and documentation) that attach to this slot
>>>> abstraction.
>>>
>>> I thought that might be the case. Too bad, it means we have to keep
>>> the slots API and the kernel will be stuck with it forever (even if
>>> some day userspace can manage key ids instead of slots).
>>
>> Yap, but I think there won't be any change like that in the near future.
>
> As far as I understand the conclusion of the discussion, the best
> practice for the keys management is to keep keys discrete including the
> Tx/Rx keys separation. On the other hand, from the OpenVPN protocol
> perspective, keys are grouped into slots and peers perform so called key
> slots swapping.
>
> As I can see, we have two options to adjust userspace application and
> kernel to each other:
> 1) implement "key slots" abstraction in Netlink API to keep kernel
> interface similar to the current OpenVPN protocol;
> 2) implement "discrete" keys management via Netlink API and move "slots"
> abstraction to the userspace application.
>
> Sabrina already mentioned that kernel will stuck with the slots
> abstraction forever. This is due to the rule that user's API should not
> be changed.
>
> Antonio, can we consider implementing the slot abstraction in the
> userspace application? It will move complexity from the kernel to the
> userspace, where it can be easy debugged and maintained.
>
> And since the keys management is part of the control plane. Keeping
> abstraction closer to the control plane implementation will allow any
> protocol modification, while keeping the kernel forward compatible.
Thanks for chiming in!
Right now the implementation is already pretty simple IMHO, there is not
much complexity to move to userspace.
And that's because ovpn in kernelspace "thinks" in terms of slots like
userspace.
If we want to go with a different approach, we have to add the
"complexity" of converting abstraction from slots to anything being
proposed here.
I presume you're advocating about moving from slots to key IDs (and
separate keys for TX and RX)?
How do you see it working in detail?
I.e. how many keys should we store and when should we purge them?
(right now we just keep 2 pair of keys - aka slots - and the lifecycle
is simply done)
And why do you think it is simpler?
One more advantage I see about using slots is that it's easy to match
the user and kernel space states: at any point in time userspace can say
"these are the pairs I have in my two slots" and kernelspace will just
mirror that, without having to care about old IDs.
Don't you think this approach is already pretty simple and less error
prone with respect to going through an abstraction conversion?
Thanks!
Cheers,
>
>>>> Hence my proposal to keep the API the same, but rework the internal for
>>>> better implementation.
>>>
>>> Yeah, that makes sense if you have that constraint imposed by the
>>> existing userspace.
>>>
>>>>
>>>>>
>>>>> Maybe you can also rework the current code to look a bit like this
>>>>> array-based proposal, and not give up the notion of slots, if that's
>>>>> something strongly built into the core of openvpn:
>>>>>
>>>>> - primary/secondary in ovpn_crypto_state become slots[2]
>>>>> - add a one-bit "primary" reference, used to look into the slots array
>>>>> - swap just flips that "primary" bit
>>>>> - TX uses slots[primary]
>>>>> - RX keeps inspecting both slots (now slot[0] and slot[1] instead of
>>>>> primary/secondary) looking for the correct keyid
>>>>> - setkey/delkey still operate on primary/secondary, but need to figure
>>>>> out whether slot[0] or slot[1] is primary/secondary based on
>>>>> ->primary
>>>>>
>>>>> It's almost identical to the current code (and API), except you don't
>>>>> need to reassign any pointers to swap keys, so it should avoid the
>>>>> rekey issue.
>>>>
>>>> This approach sounds very close to what I was aiming for, but simpler
>>>> because we have slots[2] instead of slots[8] (which means that
>>>> primary_id
>>>> can be just 'one-bit').
>>>
>>> Yes.
>>>
>>>> The only downside is that upon RX we have to check both keys.
>>>> However I don't think this is an issue as we have just 2 keys at most.
>>>>
>>>> I could even optimize the lookup by starting always from the primary
>>>> key, as
>>>> that's the one being used most of the time by the sender.
>>>
>>> Nice.
>>>
>>>> Ok, I will go with this approach you summarized here at the end.
>>>
>>> Ok. I think it should be a pretty minimal set of changes on top of the
>>> existing code, especially if you hide the primary/secondary accesses
>>> in inline helpers.
>>
>> I think so to - working on it.
>
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread
* Re: [PATCH net-next v6 12/25] ovpn: implement packet processing
2024-08-27 12:07 ` [PATCH net-next v6 12/25] ovpn: implement packet processing Antonio Quartulli
2024-09-02 14:42 ` Sabrina Dubroca
@ 2024-09-06 19:29 ` Simon Horman
2024-09-09 8:38 ` Antonio Quartulli
1 sibling, 1 reply; 58+ messages in thread
From: Simon Horman @ 2024-09-06 19:29 UTC (permalink / raw)
To: Antonio Quartulli
Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd
On Tue, Aug 27, 2024 at 02:07:52PM +0200, Antonio Quartulli wrote:
> 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>
...
> diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
...
> @@ -54,39 +56,122 @@ static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb)
> dev_sw_netstats_rx_add(peer->ovpn->dev, skb->len);
> }
>
> -static void ovpn_decrypt_post(struct sk_buff *skb, int ret)
> +void ovpn_decrypt_post(struct sk_buff *skb, int ret)
> {
> - struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;
> + struct ovpn_crypto_key_slot *ks = ovpn_skb_cb(skb)->ctx->ks;
> + struct ovpn_peer *peer = ovpn_skb_cb(skb)->ctx->peer;
> + __be16 proto;
> + __be32 *pid;
>
> - if (unlikely(ret < 0))
> + /* crypto is happening asyncronously. this function will be called
nit: asynchronously
Flagged by checkpatch.pl --codespell
> + * again later by the crypto callback with a proper return code
> + */
> + if (unlikely(ret == -EINPROGRESS))
> + return;
...
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 12/25] ovpn: implement packet processing
2024-09-06 19:29 ` Simon Horman
@ 2024-09-09 8:38 ` Antonio Quartulli
0 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-09 8:38 UTC (permalink / raw)
To: Simon Horman; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd
On 06/09/2024 21:29, Simon Horman wrote:
> On Tue, Aug 27, 2024 at 02:07:52PM +0200, Antonio Quartulli wrote:
>> 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>
>
> ...
>
>> diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
>
> ...
>
>> @@ -54,39 +56,122 @@ static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb)
>> dev_sw_netstats_rx_add(peer->ovpn->dev, skb->len);
>> }
>>
>> -static void ovpn_decrypt_post(struct sk_buff *skb, int ret)
>> +void ovpn_decrypt_post(struct sk_buff *skb, int ret)
>> {
>> - struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;
>> + struct ovpn_crypto_key_slot *ks = ovpn_skb_cb(skb)->ctx->ks;
>> + struct ovpn_peer *peer = ovpn_skb_cb(skb)->ctx->peer;
>> + __be16 proto;
>> + __be32 *pid;
>>
>> - if (unlikely(ret < 0))
>> + /* crypto is happening asyncronously. this function will be called
>
> nit: asynchronously
>
> Flagged by checkpatch.pl --codespell
Thanks! I forgot to add the codespell flag to my last checkpatch run :-(
Will fix it in the next version.
Cheers,
>
>> + * again later by the crypto callback with a proper return code
>> + */
>> + if (unlikely(ret == -EINPROGRESS))
>> + return;
>
> ...
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread
* [PATCH net-next v6 13/25] ovpn: store tunnel and transport statistics
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (11 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 12/25] ovpn: implement packet processing Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 14/25] ovpn: implement TCP transport Antonio Quartulli
` (11 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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/crypto_aead.c | 2 ++
drivers/net/ovpn/io.c | 10 ++++++++
drivers/net/ovpn/peer.c | 3 +++
drivers/net/ovpn/peer.h | 8 ++++++
drivers/net/ovpn/skb.h | 1 +
drivers/net/ovpn/stats.c | 21 +++++++++++++++
drivers/net/ovpn/stats.h | 47 ++++++++++++++++++++++++++++++++++
8 files changed, 93 insertions(+)
create mode 100644 drivers/net/ovpn/stats.c
create mode 100644 drivers/net/ovpn/stats.h
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
index ccdaeced1982..d43fda72646b 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/crypto_aead.c b/drivers/net/ovpn/crypto_aead.c
index 2e36ba8c4bfd..dab11b60ae1b 100644
--- a/drivers/net/ovpn/crypto_aead.c
+++ b/drivers/net/ovpn/crypto_aead.c
@@ -139,6 +139,7 @@ int ovpn_aead_encrypt(struct ovpn_peer *peer, struct ovpn_crypto_key_slot *ks,
aead_request_set_crypt(req, sg, sg, skb->len - head_size, iv);
aead_request_set_ad(req, OVPN_OP_SIZE_V2 + NONCE_WIRE_SIZE);
+ ovpn_skb_cb(skb)->ctx->orig_len = skb->len;
ovpn_skb_cb(skb)->ctx->peer = peer;
ovpn_skb_cb(skb)->ctx->req = req;
ovpn_skb_cb(skb)->ctx->ks = ks;
@@ -236,6 +237,7 @@ int ovpn_aead_decrypt(struct ovpn_peer *peer, struct ovpn_crypto_key_slot *ks,
aead_request_set_ad(req, NONCE_WIRE_SIZE + OVPN_OP_SIZE_V2);
+ ovpn_skb_cb(skb)->ctx->orig_len = skb->len;
ovpn_skb_cb(skb)->ctx->payload_offset = payload_offset;
ovpn_skb_cb(skb)->ctx->peer = peer;
ovpn_skb_cb(skb)->ctx->req = req;
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index 2b9311566971..82c18abc16a9 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -11,6 +11,7 @@
#include <linux/skbuff.h>
#include <net/gro_cells.h>
#include <net/gso.h>
+#include <net/ip.h>
#include "ovpnstruct.h"
#include "peer.h"
@@ -19,6 +20,7 @@
#include "crypto_aead.h"
#include "netlink.h"
#include "proto.h"
+#include "socket.h"
#include "udp.h"
#include "skb.h"
@@ -120,6 +122,11 @@ void ovpn_decrypt_post(struct sk_buff *skb, int ret)
goto drop;
}
+ /* increment RX stats */
+ ovpn_peer_stats_increment_rx(&peer->vpn_stats, skb->len);
+ ovpn_peer_stats_increment_rx(&peer->link_stats,
+ ovpn_skb_cb(skb)->ctx->orig_len);
+
kfree(ovpn_skb_cb(skb)->ctx);
ovpn_netdev_write(peer, skb);
/* skb is passed to upper layer - don't free it */
@@ -169,6 +176,9 @@ void ovpn_encrypt_post(struct sk_buff *skb, int ret)
goto err;
skb_mark_not_on_list(skb);
+ ovpn_peer_stats_increment_tx(&peer->link_stats, skb->len);
+ ovpn_peer_stats_increment_tx(&peer->vpn_stats,
+ ovpn_skb_cb(skb)->ctx->orig_len);
kfree(ovpn_skb_cb(skb)->ctx);
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 212d1210bc56..6d34c56a4a51 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -18,6 +18,7 @@
#include "main.h"
#include "netlink.h"
#include "peer.h"
+#include "socket.h"
/**
* ovpn_peer_new - allocate and initialize a new peer object
@@ -47,6 +48,8 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_struct *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 70d92cd5bd63..89f6face7187 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -10,10 +10,14 @@
#ifndef _NET_OVPN_OVPNPEER_H_
#define _NET_OVPN_OVPNPEER_H_
+#include <net/dst_cache.h>
+#include <uapi/linux/ovpn.h>
+
#include "bind.h"
#include "pktid.h"
#include "crypto.h"
#include "socket.h"
+#include "stats.h"
#include <net/dst_cache.h>
#include <uapi/linux/ovpn.h>
@@ -30,6 +34,8 @@
* @dst_cache: cache for dst_entry used to send to peer
* @bind: remote peer binding
* @halt: true if ovpn_peer_mark_delete was called
+ * @vpn_stats: per-peer in-VPN TX/RX stays
+ * @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
@@ -48,6 +54,8 @@ struct ovpn_peer {
struct dst_cache dst_cache;
struct ovpn_bind __rcu *bind;
bool halt;
+ 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/skb.h b/drivers/net/ovpn/skb.h
index 3f94efae20fb..3d9f38b081a6 100644
--- a/drivers/net/ovpn/skb.h
+++ b/drivers/net/ovpn/skb.h
@@ -23,6 +23,7 @@ struct ovpn_cb_ctx {
struct ovpn_crypto_key_slot *ks;
struct aead_request *req;
struct scatterlist sg[MAX_SKB_FRAGS + 2];
+ size_t orig_len;
unsigned int payload_offset;
};
diff --git a/drivers/net/ovpn/stats.c b/drivers/net/ovpn/stats.c
new file mode 100644
index 000000000000..a383842c3449
--- /dev/null
+++ b/drivers/net/ovpn/stats.c
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2020-2024 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 000000000000..868f49d25eaa
--- /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) 2020-2024 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_ */
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 14/25] ovpn: implement TCP transport
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (12 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 13/25] ovpn: store tunnel and transport statistics Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 15/25] ovpn: implement multi-peer support Antonio Quartulli
` (10 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
With this change ovpn is allowed to communicate to peers also via TCP.
Parsing of incoming messages is implemented through the strparser API.
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/peer.h | 37 +++
drivers/net/ovpn/socket.c | 27 +-
drivers/net/ovpn/socket.h | 7 +-
drivers/net/ovpn/tcp.c | 512 ++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/tcp.h | 42 ++++
9 files changed, 630 insertions(+), 4 deletions(-)
create mode 100644 drivers/net/ovpn/tcp.c
create mode 100644 drivers/net/ovpn/tcp.h
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index c5743288242d..ddc65bc1e218 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -118,6 +118,7 @@ config WIREGUARD_DEBUG
config OVPN
tristate "OpenVPN data channel offload"
depends on NET && INET
+ select STREAM_PARSER
select NET_UDP_TUNNEL
select DST_CACHE
select CRYPTO
diff --git a/drivers/net/ovpn/Makefile b/drivers/net/ovpn/Makefile
index d43fda72646b..f4d4bd87c851 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 82c18abc16a9..cde1c8ce5cf5 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -21,6 +21,7 @@
#include "netlink.h"
#include "proto.h"
#include "socket.h"
+#include "tcp.h"
#include "udp.h"
#include "skb.h"
@@ -186,6 +187,9 @@ void ovpn_encrypt_post(struct sk_buff *skb, int ret)
case IPPROTO_UDP:
ovpn_udp_send_skb(peer->ovpn, peer, skb);
break;
+ case IPPROTO_TCP:
+ ovpn_tcp_send_skb(peer, skb);
+ break;
default:
/* no transport configured yet */
goto err;
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index caa38f6bee2a..18fefda74fd1 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -25,6 +25,7 @@
#include "io.h"
#include "packet.h"
#include "peer.h"
+#include "tcp.h"
/* Driver info */
#define DRV_DESCRIPTION "OpenVPN data channel offload (ovpn)"
@@ -279,6 +280,8 @@ static int __init ovpn_init(void)
goto unreg_rtnl;
}
+ ovpn_tcp_init();
+
return 0;
unreg_rtnl:
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index 89f6face7187..86d4696b1529 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 <uapi/linux/ovpn.h>
#include "bind.h"
@@ -30,6 +31,18 @@
* @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.tx_work: work for deferring outgoing packet processing (TCP only)
+ * @tcp.user_queue: received packets that have to go to userspace (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
@@ -50,6 +63,30 @@ struct ovpn_peer {
struct in6_addr ipv6;
} vpn_addrs;
struct ovpn_socket *sock;
+
+ /* state of the TCP reading. Needed to keep track of how much of a
+ * single packet has already been read from the stream and how much is
+ * missing
+ */
+ struct {
+ struct strparser strp;
+ struct work_struct tx_work;
+ struct sk_buff_head user_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;
+ } 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 964b566de69f..8bb3b0cb18ec 100644
--- a/drivers/net/ovpn/socket.c
+++ b/drivers/net/ovpn/socket.c
@@ -15,6 +15,7 @@
#include "io.h"
#include "peer.h"
#include "socket.h"
+#include "tcp.h"
#include "udp.h"
static void ovpn_socket_detach(struct socket *sock)
@@ -24,6 +25,8 @@ static void ovpn_socket_detach(struct socket *sock)
if (sock->sk->sk_protocol == IPPROTO_UDP)
ovpn_udp_socket_detach(sock);
+ else if (sock->sk->sk_protocol == IPPROTO_TCP)
+ ovpn_tcp_socket_detach(sock);
sockfd_put(sock);
}
@@ -70,6 +73,8 @@ static int ovpn_socket_attach(struct socket *sock, struct ovpn_peer *peer)
if (sock->sk->sk_protocol == IPPROTO_UDP)
ret = ovpn_udp_socket_attach(sock, peer->ovpn);
+ else if (sock->sk->sk_protocol == IPPROTO_TCP)
+ ret = ovpn_tcp_socket_attach(sock, peer);
return ret;
}
@@ -131,14 +136,30 @@ struct ovpn_socket *ovpn_socket_new(struct socket *sock, struct ovpn_peer *peer)
}
ovpn_sock = kzalloc(sizeof(*ovpn_sock), GFP_KERNEL);
- if (!ovpn_sock)
- return ERR_PTR(-ENOMEM);
+ if (!ovpn_sock) {
+ ret = -ENOMEM;
+ goto err;
+ }
- ovpn_sock->ovpn = peer->ovpn;
ovpn_sock->sock = sock;
kref_init(&ovpn_sock->refcount);
+ /* TCP sockets are per-peer, therefore they are linked to their unique
+ * peer
+ */
+ if (sock->sk->sk_protocol == IPPROTO_TCP) {
+ ovpn_sock->peer = peer;
+ } else {
+ /* in UDP we only link the ovpn instance since the socket is
+ * shared among multiple peers
+ */
+ ovpn_sock->ovpn = peer->ovpn;
+ }
+
rcu_assign_sk_user_data(sock->sk, ovpn_sock);
return ovpn_sock;
+err:
+ ovpn_socket_detach(sock);
+ return ERR_PTR(ret);
}
diff --git a/drivers/net/ovpn/socket.h b/drivers/net/ovpn/socket.h
index 5ad9c5073b08..e9f0035d706e 100644
--- a/drivers/net/ovpn/socket.h
+++ b/drivers/net/ovpn/socket.h
@@ -20,12 +20,17 @@ struct ovpn_peer;
/**
* struct ovpn_socket - a kernel socket referenced in the ovpn code
* @ovpn: ovpn instance owning this socket (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
*/
struct ovpn_socket {
- struct ovpn_struct *ovpn;
+ union {
+ struct ovpn_struct *ovpn;
+ struct ovpn_peer *peer;
+ };
+
struct socket *sock;
struct kref refcount;
struct rcu_head rcu;
diff --git a/drivers/net/ovpn/tcp.c b/drivers/net/ovpn/tcp.c
new file mode 100644
index 000000000000..5f2d0fa41415
--- /dev/null
+++ b/drivers/net/ovpn/tcp.c
@@ -0,0 +1,512 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2024 OpenVPN, Inc.
+ *
+ * Author: Antonio Quartulli <antonio@openvpn.net>
+ */
+
+#include <linux/skbuff.h>
+#include <net/hotdata.h>
+#include <net/inet_common.h>
+#include <net/tcp.h>
+#include <net/route.h>
+#include <trace/events/sock.h>
+
+#include "ovpnstruct.h"
+#include "main.h"
+#include "io.h"
+#include "packet.h"
+#include "peer.h"
+#include "proto.h"
+#include "skb.h"
+#include "socket.h"
+#include "tcp.h"
+
+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;
+static struct proto_ops ovpn_tcp6_ops;
+static DEFINE_MUTEX(tcp6_prot_mutex);
+
+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.
+ * Here we read those two bytes and move the skb data pointer to the
+ * beginning of the packet
+ */
+
+ 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 int ovpn_tcp_to_userspace(struct ovpn_socket *sock, struct sk_buff *skb)
+{
+ struct sock *sk = sock->sock->sk;
+
+ skb_set_owner_r(skb, sk);
+ memset(skb->cb, 0, sizeof(skb->cb));
+ skb_queue_tail(&sock->peer->tcp.user_queue, skb);
+ sock->peer->tcp.sk_cb.sk_data_ready(sk);
+
+ return 0;
+}
+
+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;
+
+ /* ensure skb->data points to the beginning of the openvpn packet */
+ if (!pskb_pull(skb, off)) {
+ net_warn_ratelimited("%s: packet too small\n",
+ peer->ovpn->dev->name);
+ 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\n",
+ peer->ovpn->dev->name);
+ 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, 1)) {
+ net_warn_ratelimited("%s: packet too small to fetch opcode\n",
+ peer->ovpn->dev->name);
+ goto err;
+ }
+
+ /* DATA_V2 packets are handled in kernel, the rest goes to user space */
+ if (likely(ovpn_opcode_from_skb(skb, 0) == OVPN_DATA_V2)) {
+ /* 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);
+ } else {
+ /* The packet size header must be there when sending the packet
+ * to userspace, therefore we put it back
+ */
+ skb_push(skb, 2);
+ if (ovpn_tcp_to_userspace(peer->sock, skb) < 0) {
+ net_warn_ratelimited("%s: cannot send skb to userspace\n",
+ peer->ovpn->dev->name);
+ goto err;
+ }
+ }
+
+ return;
+err:
+ netdev_err(peer->ovpn->dev,
+ "cannot process incoming TCP data for peer %u\n", peer->id);
+ 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 (!sock || !sock->peer) {
+ rcu_read_unlock();
+ return -EBADF;
+ }
+ /* we take a reference to the peer linked to this TCP socket, because
+ * in turn the peer holds a reference to the socket itself.
+ * By doing so we also ensure that the peer stays alive along with
+ * the socket while executing this function
+ */
+ ovpn_peer_hold(sock->peer);
+ 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 socket *sock)
+{
+ struct ovpn_socket *ovpn_sock;
+ struct ovpn_peer *peer;
+
+ if (!sock)
+ return;
+
+ rcu_read_lock();
+ ovpn_sock = rcu_dereference_sk_user_data(sock->sk);
+
+ if (!ovpn_sock->peer) {
+ rcu_read_unlock();
+ return;
+ }
+
+ peer = ovpn_sock->peer;
+ 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);
+
+ rcu_read_unlock();
+
+ /* cancel any ongoing work. Done after removing the CBs so that these
+ * workers cannot be re-armed
+ */
+ cancel_work_sync(&peer->tcp.tx_work);
+ strp_done(&peer->tcp.strp);
+}
+
+static void ovpn_tcp_send_sock(struct ovpn_peer *peer)
+{
+ 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(peer->sock->sock->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",
+ peer->ovpn->dev->name, peer->id,
+ ret);
+
+ /* in case of TCP error we can't recover the VPN
+ * stream therefore we abort the connection
+ */
+ ovpn_peer_del(peer,
+ OVPN_DEL_PEER_REASON_TRANSPORT_ERROR);
+ break;
+ }
+
+ 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)
+ dev_sw_netstats_tx_add(peer->ovpn->dev, 1, skb->len);
+
+ 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;
+}
+
+static void ovpn_tcp_tx_work(struct work_struct *work)
+{
+ struct ovpn_peer *peer;
+
+ peer = container_of(work, struct ovpn_peer, tcp.tx_work);
+
+ lock_sock(peer->sock->sock->sk);
+ ovpn_tcp_send_sock(peer);
+ release_sock(peer->sock->sock->sk);
+}
+
+void ovpn_tcp_send_sock_skb(struct ovpn_peer *peer, struct sk_buff *skb)
+{
+ if (peer->tcp.out_msg.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);
+}
+
+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;
+
+ rcu_read_lock();
+ sock = rcu_dereference_sk_user_data(sk);
+ peer = sock->peer;
+ if (unlikely(!ovpn_peer_hold(peer))) {
+ rcu_read_unlock();
+ return -EIO;
+ }
+ rcu_read_unlock();
+
+ if (msg->msg_flags & ~MSG_DONTWAIT) {
+ ret = -EOPNOTSUPP;
+ goto peer_free;
+ }
+
+ lock_sock(sk);
+
+ if (peer->tcp.out_msg.skb) {
+ ret = -EAGAIN;
+ goto unlock;
+ }
+
+ 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",
+ sock->peer->ovpn->dev->name, ret);
+ goto unlock;
+ }
+
+ 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",
+ sock->peer->ovpn->dev->name, ret);
+ goto unlock;
+ }
+
+ ovpn_tcp_send_sock_skb(sock->peer, skb);
+ ret = size;
+unlock:
+ release_sock(sk);
+peer_free:
+ 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);
+ 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);
+ schedule_work(&sock->peer->tcp.tx_work);
+ sock->peer->tcp.sk_cb.sk_write_space(sk);
+ rcu_read_unlock();
+}
+
+static void ovpn_tcp_build_protos(struct proto *ovpn_tcp_prot,
+ struct proto_ops *ovpn_tcp_ops,
+ const struct proto *orig_prot,
+ const struct proto_ops *orig_ops);
+
+/* Set TCP encapsulation callbacks */
+int ovpn_tcp_socket_attach(struct socket *sock, struct ovpn_peer *peer)
+{
+ 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;
+
+ /* sanity check */
+ if (sock->sk->sk_protocol != IPPROTO_TCP) {
+ netdev_err(peer->ovpn->dev,
+ "provided socket is not TCP as expected\n");
+ return -EINVAL;
+ }
+
+ /* only a fully connected socket are expected. Connection should be
+ * handled in userspace
+ */
+ if (sock->sk->sk_state != TCP_ESTABLISHED) {
+ netdev_err(peer->ovpn->dev,
+ "provided TCP socket is not in ESTABLISHED state: %d\n",
+ sock->sk->sk_state);
+ return -EINVAL;
+ }
+
+ lock_sock(sock->sk);
+
+ ret = strp_init(&peer->tcp.strp, sock->sk, &cb);
+ if (ret < 0) {
+ DEBUG_NET_WARN_ON_ONCE(1);
+ release_sock(sock->sk);
+ return ret;
+ }
+
+ INIT_WORK(&peer->tcp.tx_work, ovpn_tcp_tx_work);
+ __sk_dst_reset(sock->sk);
+ strp_check_rcv(&peer->tcp.strp);
+ skb_queue_head_init(&peer->tcp.user_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 {
+ mutex_lock(&tcp6_prot_mutex);
+ if (!ovpn_tcp6_prot.recvmsg)
+ ovpn_tcp_build_protos(&ovpn_tcp6_prot, &ovpn_tcp6_ops,
+ sock->sk->sk_prot,
+ sock->sk->sk_socket->ops);
+ mutex_unlock(&tcp6_prot_mutex);
+
+ 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;
+
+ release_sock(sock->sk);
+ return 0;
+}
+
+static void ovpn_tcp_close(struct sock *sk, long timeout)
+{
+ struct ovpn_socket *sock;
+
+ rcu_read_lock();
+ sock = rcu_dereference_sk_user_data(sk);
+
+ strp_stop(&sock->peer->tcp.strp);
+ barrier();
+
+ tcp_close(sk, timeout);
+
+ ovpn_peer_del(sock->peer, OVPN_DEL_PEER_REASON_TRANSPORT_ERROR);
+ rcu_read_unlock();
+}
+
+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 (!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 *tcp_prot,
+ struct proto_ops *tcp_ops,
+ const struct proto *orig_prot,
+ const struct proto_ops *orig_ops)
+{
+ memcpy(tcp_prot, orig_prot, sizeof(*tcp_prot));
+ memcpy(tcp_ops, orig_ops, sizeof(*tcp_ops));
+ tcp_prot->recvmsg = ovpn_tcp_recvmsg;
+ tcp_prot->sendmsg = ovpn_tcp_sendmsg;
+ tcp_prot->close = ovpn_tcp_close;
+ tcp_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);
+}
diff --git a/drivers/net/ovpn/tcp.h b/drivers/net/ovpn/tcp.h
new file mode 100644
index 000000000000..11c12a9cbe1b
--- /dev/null
+++ b/drivers/net/ovpn/tcp.h
@@ -0,0 +1,42 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* OpenVPN data channel offload
+ *
+ * Copyright (C) 2019-2024 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"
+
+void __init ovpn_tcp_init(void);
+
+int ovpn_tcp_socket_attach(struct socket *sock, struct ovpn_peer *peer);
+void ovpn_tcp_socket_detach(struct socket *sock);
+void ovpn_tcp_send_sock_skb(struct ovpn_peer *peer, struct sk_buff *skb);
+
+/* 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.
+ */
+static inline void ovpn_tcp_send_skb(struct ovpn_peer *peer,
+ struct sk_buff *skb)
+{
+ u16 len = skb->len;
+
+ *(__be16 *)__skb_push(skb, sizeof(u16)) = htons(len);
+
+ bh_lock_sock(peer->sock->sock->sk);
+ ovpn_tcp_send_sock_skb(peer, skb);
+ bh_unlock_sock(peer->sock->sock->sk);
+}
+
+#endif /* _NET_OVPN_TCP_H_ */
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 15/25] ovpn: implement multi-peer support
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (13 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 14/25] ovpn: implement TCP transport Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-09-03 14:40 ` Sabrina Dubroca
2024-08-27 12:07 ` [PATCH net-next v6 16/25] ovpn: implement peer lookup logic Antonio Quartulli
` (9 subsequent siblings)
24 siblings, 1 reply; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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 | 49 +++++++++-
drivers/net/ovpn/ovpnstruct.h | 22 +++++
drivers/net/ovpn/peer.c | 167 +++++++++++++++++++++++++++++++++-
drivers/net/ovpn/peer.h | 9 ++
4 files changed, 244 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index 18fefda74fd1..94d2ee87807f 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -54,14 +54,53 @@ static void ovpn_struct_free(struct net_device *net)
struct ovpn_struct *ovpn = netdev_priv(net);
gro_cells_destroy(&ovpn->gro_cells);
+ kfree(ovpn->peers);
rcu_barrier();
}
static int ovpn_net_init(struct net_device *dev)
{
struct ovpn_struct *ovpn = netdev_priv(dev);
+ int i, err = gro_cells_init(&ovpn->gro_cells, dev);
+ struct in_device *dev_v4;
- return gro_cells_init(&ovpn->gro_cells, dev);
+ if (err)
+ return err;
+
+ if (ovpn->mode == OVPN_MODE_MP) {
+ dev_v4 = __in_dev_get_rtnl(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(dev), SEND_REDIRECTS) = false;
+ }
+
+ /* the peer container is fairly large, therefore we dynamically
+ * allocate it only when needed
+ */
+ ovpn->peers = kzalloc(sizeof(*ovpn->peers), GFP_KERNEL);
+ if (!ovpn->peers)
+ return -ENOMEM;
+
+ spin_lock_init(&ovpn->peers->lock_by_id);
+ spin_lock_init(&ovpn->peers->lock_by_vpn_addr);
+ spin_lock_init(&ovpn->peers->lock_by_transp_addr);
+
+ for (i = 0; i < ARRAY_SIZE(ovpn->peers->by_id); i++) {
+ INIT_HLIST_HEAD(&ovpn->peers->by_id[i]);
+ INIT_HLIST_HEAD(&ovpn->peers->by_vpn_addr[i]);
+ INIT_HLIST_NULLS_HEAD(&ovpn->peers->by_transp_addr[i],
+ i);
+ }
+ }
+
+ return 0;
}
static int ovpn_net_open(struct net_device *dev)
@@ -210,8 +249,14 @@ void ovpn_iface_destruct(struct ovpn_struct *ovpn)
ovpn->registered = false;
- if (ovpn->mode == OVPN_MODE_P2P)
+ switch (ovpn->mode) {
+ case OVPN_MODE_P2P:
ovpn_peer_release_p2p(ovpn);
+ break;
+ default:
+ ovpn_peers_free(ovpn);
+ break;
+ }
}
static int ovpn_netdev_notifier_call(struct notifier_block *nb,
diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h
index 65497ce115aa..3d74e79fcdf3 100644
--- a/drivers/net/ovpn/ovpnstruct.h
+++ b/drivers/net/ovpn/ovpnstruct.h
@@ -14,6 +14,26 @@
#include <net/net_trackers.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_addr: table of peers indexed by VPN IP address
+ * @by_transp_addr: table of peers indexed by transport address (items can be
+ * rehashed on the fly due to peer IP change)
+ * @lock_by_id: protects writes to peers by_id table
+ * @lock_by_vpn_addr: protects writes to peers by_vpn_addr table
+ * @lock_by_transp_addr: protects writes to peers by_transp_addr table
+ */
+struct ovpn_peer_collection {
+ DECLARE_HASHTABLE(by_id, 12);
+ DECLARE_HASHTABLE(by_vpn_addr, 12);
+ struct hlist_nulls_head by_transp_addr[1 << 12];
+
+ spinlock_t lock_by_id; /* protects writes to by_id */
+ spinlock_t lock_by_vpn_addr; /* protects by_vpn_addr */
+ spinlock_t lock_by_transp_addr; /* protects by_transp_addr */
+};
+
/**
* struct ovpn_struct - per ovpn interface state
* @dev: the actual netdev representing the tunnel
@@ -21,6 +41,7 @@
* @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
* @dev_list: entry for the module wide device list
* @gro_cells: pointer to the Generic Receive Offload cell
@@ -31,6 +52,7 @@ struct ovpn_struct {
bool registered;
enum ovpn_mode mode;
spinlock_t lock; /* protect writing to the ovpn_struct object */
+ struct ovpn_peer_collection *peers;
struct ovpn_peer __rcu *peer;
struct list_head dev_list;
struct gro_cells gro_cells;
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 6d34c56a4a51..58037c2cbcca 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 "ovpnstruct.h"
#include "bind.h"
@@ -309,6 +310,92 @@ bool ovpn_peer_check_by_src(struct ovpn_struct *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_struct *ovpn, struct ovpn_peer *peer)
+{
+ struct sockaddr_storage sa = { 0 };
+ struct hlist_nulls_head *nhead;
+ struct sockaddr_in6 *sa6;
+ struct sockaddr_in *sa4;
+ struct hlist_head *head;
+ struct ovpn_bind *bind;
+ struct ovpn_peer *tmp;
+ size_t salen;
+
+ spin_lock_bh(&ovpn->peers->lock_by_id);
+ /* do not add duplicates */
+ tmp = ovpn_peer_get_by_id(ovpn, peer->id);
+ if (tmp) {
+ ovpn_peer_put(tmp);
+ spin_unlock_bh(&ovpn->peers->lock_by_id);
+ return -EEXIST;
+ }
+
+ hlist_add_head_rcu(&peer->hash_entry_id,
+ ovpn_get_hash_head(ovpn->peers->by_id, &peer->id,
+ sizeof(peer->id)));
+ spin_unlock_bh(&ovpn->peers->lock_by_id);
+
+ 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:
+ return -EPROTONOSUPPORT;
+ }
+
+ nhead = ovpn_get_hash_head(ovpn->peers->by_transp_addr, &sa,
+ salen);
+ spin_lock_bh(&ovpn->peers->lock_by_transp_addr);
+ hlist_nulls_add_head_rcu(&peer->hash_entry_transp_addr, nhead);
+ spin_unlock_bh(&ovpn->peers->lock_by_transp_addr);
+ }
+
+ spin_lock_bh(&ovpn->peers->lock_by_vpn_addr);
+ if (peer->vpn_addrs.ipv4.s_addr != htonl(INADDR_ANY)) {
+ head = ovpn_get_hash_head(ovpn->peers->by_vpn_addr,
+ &peer->vpn_addrs.ipv4,
+ sizeof(peer->vpn_addrs.ipv4));
+ hlist_add_head_rcu(&peer->hash_entry_addr4, head);
+ }
+
+ if (!ipv6_addr_any(&peer->vpn_addrs.ipv6)) {
+ head = ovpn_get_hash_head(ovpn->peers->by_vpn_addr,
+ &peer->vpn_addrs.ipv6,
+ sizeof(peer->vpn_addrs.ipv6));
+ hlist_add_head_rcu(&peer->hash_entry_addr6, head);
+ }
+ spin_unlock_bh(&ovpn->peers->lock_by_vpn_addr);
+
+ return 0;
+}
+
/**
* ovpn_peer_add_p2p - add peer to related tables in a P2P instance
* @ovpn: the instance to add the peer to
@@ -349,6 +436,8 @@ static int ovpn_peer_add_p2p(struct ovpn_struct *ovpn, struct ovpn_peer *peer)
int ovpn_peer_add(struct ovpn_struct *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:
@@ -356,6 +445,56 @@ int ovpn_peer_add(struct ovpn_struct *ovpn, struct ovpn_peer *peer)
}
}
+/**
+ * ovpn_peer_unhash - remove peer reference from all hashtables
+ * @peer: the peer to remove
+ * @reason: the delete reason to attach to the peer
+ */
+static void ovpn_peer_unhash(struct ovpn_peer *peer,
+ enum ovpn_del_peer_reason reason)
+ __must_hold(&ovpn->peers->lock_by_id)
+{
+ hlist_del_init_rcu(&peer->hash_entry_id);
+
+ spin_lock_bh(&peer->ovpn->peers->lock_by_vpn_addr);
+ hlist_del_init_rcu(&peer->hash_entry_addr4);
+ hlist_del_init_rcu(&peer->hash_entry_addr6);
+ spin_unlock_bh(&peer->ovpn->peers->lock_by_vpn_addr);
+
+ spin_lock_bh(&peer->ovpn->peers->lock_by_transp_addr);
+ hlist_nulls_del_init_rcu(&peer->hash_entry_transp_addr);
+ spin_unlock_bh(&peer->ovpn->peers->lock_by_transp_addr);
+
+ ovpn_peer_put(peer);
+ peer->delete_reason = reason;
+}
+
+/**
+ * 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)
+ *
+ * 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)
+ __must_hold(&peer->ovpn->peers->lock_by_id)
+{
+ struct ovpn_peer *tmp;
+ int ret = -ENOENT;
+
+ tmp = ovpn_peer_get_by_id(peer->ovpn, peer->id);
+ if (tmp == peer) {
+ ovpn_peer_unhash(peer, reason);
+ ret = 0;
+ }
+
+ if (tmp)
+ ovpn_peer_put(tmp);
+
+ return ret;
+}
+
/**
* ovpn_peer_del_p2p - delete peer from related tables in a P2P instance
* @peer: the peer to delete
@@ -411,10 +550,36 @@ void ovpn_peer_release_p2p(struct ovpn_struct *ovpn)
*/
int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason)
{
+ int ret;
+
switch (peer->ovpn->mode) {
+ case OVPN_MODE_MP:
+ spin_lock_bh(&peer->ovpn->peers->lock_by_id);
+ ret = ovpn_peer_del_mp(peer, reason);
+ spin_unlock_bh(&peer->ovpn->peers->lock_by_id);
+ return ret;
case OVPN_MODE_P2P:
- return ovpn_peer_del_p2p(peer, reason);
+ spin_lock_bh(&peer->ovpn->lock);
+ ret = ovpn_peer_del_p2p(peer, reason);
+ spin_unlock_bh(&peer->ovpn->lock);
+ return ret;
default:
return -EOPNOTSUPP;
}
}
+
+/**
+ * ovpn_peers_free - free all peers in the instance
+ * @ovpn: the instance whose peers should be released
+ */
+void ovpn_peers_free(struct ovpn_struct *ovpn)
+{
+ struct hlist_node *tmp;
+ struct ovpn_peer *peer;
+ int bkt;
+
+ spin_lock_bh(&ovpn->peers->lock_by_id);
+ hash_for_each_safe(ovpn->peers->by_id, bkt, tmp, peer, hash_entry_id)
+ ovpn_peer_unhash(peer, OVPN_DEL_PEER_REASON_TEARDOWN);
+ spin_unlock_bh(&ovpn->peers->lock_by_id);
+}
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index 86d4696b1529..dc51cc93ef20 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -30,6 +30,10 @@
* @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)
@@ -62,6 +66,10 @@ struct ovpn_peer {
struct in_addr ipv4;
struct in6_addr ipv6;
} vpn_addrs;
+ struct hlist_node hash_entry_id;
+ struct hlist_node hash_entry_addr4;
+ struct hlist_node hash_entry_addr6;
+ struct hlist_nulls_node hash_entry_transp_addr;
struct ovpn_socket *sock;
/* state of the TCP reading. Needed to keep track of how much of a
@@ -126,6 +134,7 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_struct *ovpn, u32 id);
int ovpn_peer_add(struct ovpn_struct *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_struct *ovpn);
+void ovpn_peers_free(struct ovpn_struct *ovpn);
struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_struct *ovpn,
struct sk_buff *skb);
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 15/25] ovpn: implement multi-peer support
2024-08-27 12:07 ` [PATCH net-next v6 15/25] ovpn: implement multi-peer support Antonio Quartulli
@ 2024-09-03 14:40 ` Sabrina Dubroca
2024-09-04 10:10 ` Sabrina Dubroca
2024-09-05 8:02 ` Antonio Quartulli
0 siblings, 2 replies; 58+ messages in thread
From: Sabrina Dubroca @ 2024-09-03 14:40 UTC (permalink / raw)
To: Antonio Quartulli; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
2024-08-27, 14:07:55 +0200, Antonio Quartulli wrote:
> static int ovpn_net_init(struct net_device *dev)
> {
> struct ovpn_struct *ovpn = netdev_priv(dev);
> + int i, err = gro_cells_init(&ovpn->gro_cells, dev);
I'm not a fan of "hiding" the gro_cells_init call up here. I'd prefer
if this was done just before the corresponding "if (err)".
> + struct in_device *dev_v4;
>
> - return gro_cells_init(&ovpn->gro_cells, dev);
> + if (err)
> + return err;
> +
> + if (ovpn->mode == OVPN_MODE_MP) {
> + dev_v4 = __in_dev_get_rtnl(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(dev), SEND_REDIRECTS) = false;
> + }
> +
> + /* the peer container is fairly large, therefore we dynamically
> + * allocate it only when needed
> + */
> + ovpn->peers = kzalloc(sizeof(*ovpn->peers), GFP_KERNEL);
> + if (!ovpn->peers)
missing gro_cells_destroy
> + return -ENOMEM;
> +
> + spin_lock_init(&ovpn->peers->lock_by_id);
> + spin_lock_init(&ovpn->peers->lock_by_vpn_addr);
> + spin_lock_init(&ovpn->peers->lock_by_transp_addr);
What's the benefit of having 3 separate locks instead of a single lock
protecting all the hashtables?
> +
> + for (i = 0; i < ARRAY_SIZE(ovpn->peers->by_id); i++) {
> + INIT_HLIST_HEAD(&ovpn->peers->by_id[i]);
> + INIT_HLIST_HEAD(&ovpn->peers->by_vpn_addr[i]);
> + INIT_HLIST_NULLS_HEAD(&ovpn->peers->by_transp_addr[i],
> + i);
> + }
> + }
> +
> + return 0;
> }
> +static int ovpn_peer_add_mp(struct ovpn_struct *ovpn, struct ovpn_peer *peer)
> +{
> + struct sockaddr_storage sa = { 0 };
> + struct hlist_nulls_head *nhead;
> + struct sockaddr_in6 *sa6;
> + struct sockaddr_in *sa4;
> + struct hlist_head *head;
> + struct ovpn_bind *bind;
> + struct ovpn_peer *tmp;
> + size_t salen;
> +
> + spin_lock_bh(&ovpn->peers->lock_by_id);
> + /* do not add duplicates */
> + tmp = ovpn_peer_get_by_id(ovpn, peer->id);
> + if (tmp) {
> + ovpn_peer_put(tmp);
> + spin_unlock_bh(&ovpn->peers->lock_by_id);
> + return -EEXIST;
> + }
> +
> + hlist_add_head_rcu(&peer->hash_entry_id,
> + ovpn_get_hash_head(ovpn->peers->by_id, &peer->id,
> + sizeof(peer->id)));
> + spin_unlock_bh(&ovpn->peers->lock_by_id);
> +
> + 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:
And remove from the by_id hashtable? Or is that handled somewhere that
I missed (I don't think ovpn_peer_unhash gets called in that case)?
> + return -EPROTONOSUPPORT;
> + }
> +
--
Sabrina
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 15/25] ovpn: implement multi-peer support
2024-09-03 14:40 ` Sabrina Dubroca
@ 2024-09-04 10:10 ` Sabrina Dubroca
2024-09-06 13:26 ` Antonio Quartulli
2024-09-05 8:02 ` Antonio Quartulli
1 sibling, 1 reply; 58+ messages in thread
From: Sabrina Dubroca @ 2024-09-04 10:10 UTC (permalink / raw)
To: Antonio Quartulli; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
2024-09-03, 16:40:51 +0200, Sabrina Dubroca wrote:
> 2024-08-27, 14:07:55 +0200, Antonio Quartulli wrote:
> > +static int ovpn_peer_add_mp(struct ovpn_struct *ovpn, struct ovpn_peer *peer)
> > +{
> > + struct sockaddr_storage sa = { 0 };
> > + struct hlist_nulls_head *nhead;
> > + struct sockaddr_in6 *sa6;
> > + struct sockaddr_in *sa4;
> > + struct hlist_head *head;
> > + struct ovpn_bind *bind;
> > + struct ovpn_peer *tmp;
> > + size_t salen;
> > +
> > + spin_lock_bh(&ovpn->peers->lock_by_id);
> > + /* do not add duplicates */
> > + tmp = ovpn_peer_get_by_id(ovpn, peer->id);
> > + if (tmp) {
> > + ovpn_peer_put(tmp);
> > + spin_unlock_bh(&ovpn->peers->lock_by_id);
> > + return -EEXIST;
> > + }
> > +
> > + hlist_add_head_rcu(&peer->hash_entry_id,
> > + ovpn_get_hash_head(ovpn->peers->by_id, &peer->id,
> > + sizeof(peer->id)));
> > + spin_unlock_bh(&ovpn->peers->lock_by_id);
> > +
> > + bind = rcu_dereference_protected(peer->bind, true);
What protects us here? We just released lock_by_id and we're not
holding peer->lock.
> > + /* 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:
>
> And remove from the by_id hashtable? Or is that handled somewhere that
> I missed (I don't think ovpn_peer_unhash gets called in that case)?
ovpn_nl_set_peer_doit does:
ret = ovpn_peer_add(ovpn, peer);
if (ret < 0) {
[...]
/* release right away because peer is not really used in any
* context
*/
ovpn_peer_release(peer);
kfree(peer);
But if we fail at this stage, the peer was published in the by_id
hashtable and could be used.
Although AFAICT, ovpn can never create a bind with family !=
AF_INET{,6}, so this is not a real issue -- in that case I guess a
DEBUG_NET_WARN_ON_ONCE with a comment that this should never happen
would be acceptable (but I'd still remove the peer from by_id and go
through the proper release path instead of direct kfree in
ovpn_nl_set_peer_doit). Otherwise, you'd have to reorder things in
this function so that all failures are handled before the peer is
added to any hashtable.
> > + return -EPROTONOSUPPORT;
> > + }
> > +
--
Sabrina
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 15/25] ovpn: implement multi-peer support
2024-09-04 10:10 ` Sabrina Dubroca
@ 2024-09-06 13:26 ` Antonio Quartulli
0 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-06 13:26 UTC (permalink / raw)
To: Sabrina Dubroca; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
On 04/09/2024 12:10, Sabrina Dubroca wrote:
> 2024-09-03, 16:40:51 +0200, Sabrina Dubroca wrote:
>> 2024-08-27, 14:07:55 +0200, Antonio Quartulli wrote:
>>> +static int ovpn_peer_add_mp(struct ovpn_struct *ovpn, struct ovpn_peer *peer)
>>> +{
>>> + struct sockaddr_storage sa = { 0 };
>>> + struct hlist_nulls_head *nhead;
>>> + struct sockaddr_in6 *sa6;
>>> + struct sockaddr_in *sa4;
>>> + struct hlist_head *head;
>>> + struct ovpn_bind *bind;
>>> + struct ovpn_peer *tmp;
>>> + size_t salen;
>>> +
>>> + spin_lock_bh(&ovpn->peers->lock_by_id);
>>> + /* do not add duplicates */
>>> + tmp = ovpn_peer_get_by_id(ovpn, peer->id);
>>> + if (tmp) {
>>> + ovpn_peer_put(tmp);
>>> + spin_unlock_bh(&ovpn->peers->lock_by_id);
>>> + return -EEXIST;
>>> + }
>>> +
>>> + hlist_add_head_rcu(&peer->hash_entry_id,
>>> + ovpn_get_hash_head(ovpn->peers->by_id, &peer->id,
>>> + sizeof(peer->id)));
>>> + spin_unlock_bh(&ovpn->peers->lock_by_id);
>>> +
>>> + bind = rcu_dereference_protected(peer->bind, true);
>
> What protects us here? We just released lock_by_id and we're not
> holding peer->lock.
hmm. I think originally it was not possible to hold this peer in any
other context since the peer was stil being added.
But now we have added it to the by_id table already, so we cannot assume
that anymore.
Maybe I should simply move this assignment before the
hlist_add_head_rcu() to regain that assumption..
>
>>> + /* 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:
>>
>> And remove from the by_id hashtable? Or is that handled somewhere that
>> I missed (I don't think ovpn_peer_unhash gets called in that case)?
>
> ovpn_nl_set_peer_doit does:
>
> ret = ovpn_peer_add(ovpn, peer);
> if (ret < 0) {
> [...]
> /* release right away because peer is not really used in any
> * context
> */
> ovpn_peer_release(peer);
> kfree(peer);
>
>
> But if we fail at this stage, the peer was published in the by_id
> hashtable and could be used.
>
> Although AFAICT, ovpn can never create a bind with family !=
> AF_INET{,6}, so this is not a real issue -- in that case I guess a
> DEBUG_NET_WARN_ON_ONCE with a comment that this should never happen
> would be acceptable (but I'd still remove the peer from by_id and go
> through the proper release path instead of direct kfree in
> ovpn_nl_set_peer_doit). Otherwise, you'd have to reorder things in
> this function so that all failures are handled before the peer is
> added to any hashtable.
To be honest I don't mind adding a pre-check and error out immediately.
I don't like adding a peer to the table that is actually failing basic
sanity checks.
Thanks!
>
>>> + return -EPROTONOSUPPORT;
>>> + }
>>> +
>
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread
* Re: [PATCH net-next v6 15/25] ovpn: implement multi-peer support
2024-09-03 14:40 ` Sabrina Dubroca
2024-09-04 10:10 ` Sabrina Dubroca
@ 2024-09-05 8:02 ` Antonio Quartulli
2024-09-05 10:47 ` Sabrina Dubroca
1 sibling, 1 reply; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-05 8:02 UTC (permalink / raw)
To: Sabrina Dubroca; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
On 03/09/2024 16:40, Sabrina Dubroca wrote:
> 2024-08-27, 14:07:55 +0200, Antonio Quartulli wrote:
>> static int ovpn_net_init(struct net_device *dev)
>> {
>> struct ovpn_struct *ovpn = netdev_priv(dev);
>> + int i, err = gro_cells_init(&ovpn->gro_cells, dev);
>
> I'm not a fan of "hiding" the gro_cells_init call up here. I'd prefer
> if this was done just before the corresponding "if (err)".
I am all with you, but I remember in the past something complaining
about "variable declared and then re-assigned right after".
But maybe this is not the case anymore.
Will move the initialization down.
>
>> + struct in_device *dev_v4;
>>
>> - return gro_cells_init(&ovpn->gro_cells, dev);
>> + if (err)
>> + return err;
>> +
>> + if (ovpn->mode == OVPN_MODE_MP) {
>> + dev_v4 = __in_dev_get_rtnl(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(dev), SEND_REDIRECTS) = false;
>> + }
>> +
>> + /* the peer container is fairly large, therefore we dynamically
>> + * allocate it only when needed
>> + */
>> + ovpn->peers = kzalloc(sizeof(*ovpn->peers), GFP_KERNEL);
>> + if (!ovpn->peers)
>
> missing gro_cells_destroy
ACK
>
>> + return -ENOMEM;
>> +
>> + spin_lock_init(&ovpn->peers->lock_by_id);
>> + spin_lock_init(&ovpn->peers->lock_by_vpn_addr);
>> + spin_lock_init(&ovpn->peers->lock_by_transp_addr);
>
> What's the benefit of having 3 separate locks instead of a single lock
> protecting all the hashtables?
The main reason was to avoid a deadlock - I thought I had added a
comment about it...
The problem was a deadlock between acquiring peer->lock and
ovpn->peers->lock in float() and in then opposite sequence in peers_free().
(IIRC this happens due to ovpn_peer_reset_sockaddr() acquiring peer->lock)
Splitting the larger peers->lock allowed me to avoid this scenario,
because I don't need to jump through any hoop to coordinate access to
different hashtables.
>
>> +
>> + for (i = 0; i < ARRAY_SIZE(ovpn->peers->by_id); i++) {
>> + INIT_HLIST_HEAD(&ovpn->peers->by_id[i]);
>> + INIT_HLIST_HEAD(&ovpn->peers->by_vpn_addr[i]);
>> + INIT_HLIST_NULLS_HEAD(&ovpn->peers->by_transp_addr[i],
>> + i);
>> + }
>> + }
>> +
>> + return 0;
>> }
>
>> +static int ovpn_peer_add_mp(struct ovpn_struct *ovpn, struct ovpn_peer *peer)
>> +{
>> + struct sockaddr_storage sa = { 0 };
>> + struct hlist_nulls_head *nhead;
>> + struct sockaddr_in6 *sa6;
>> + struct sockaddr_in *sa4;
>> + struct hlist_head *head;
>> + struct ovpn_bind *bind;
>> + struct ovpn_peer *tmp;
>> + size_t salen;
>> +
>> + spin_lock_bh(&ovpn->peers->lock_by_id);
>> + /* do not add duplicates */
>> + tmp = ovpn_peer_get_by_id(ovpn, peer->id);
>> + if (tmp) {
>> + ovpn_peer_put(tmp);
>> + spin_unlock_bh(&ovpn->peers->lock_by_id);
>> + return -EEXIST;
>> + }
>> +
>> + hlist_add_head_rcu(&peer->hash_entry_id,
>> + ovpn_get_hash_head(ovpn->peers->by_id, &peer->id,
>> + sizeof(peer->id)));
>> + spin_unlock_bh(&ovpn->peers->lock_by_id);
>> +
>> + 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:
>
> And remove from the by_id hashtable? Or is that handled somewhere that
> I missed (I don't think ovpn_peer_unhash gets called in that case)?
No we don't call unhash in this case as we assume the adding just failed
entirely.
I will add the removal before returning the error (moving the add below
the switch would extend the locked area too much.)
>
>> + return -EPROTONOSUPPORT;
>> + }
>> +
>
Thanks a lot
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 15/25] ovpn: implement multi-peer support
2024-09-05 8:02 ` Antonio Quartulli
@ 2024-09-05 10:47 ` Sabrina Dubroca
2024-09-09 9:12 ` Antonio Quartulli
0 siblings, 1 reply; 58+ messages in thread
From: Sabrina Dubroca @ 2024-09-05 10:47 UTC (permalink / raw)
To: Antonio Quartulli; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
2024-09-05, 10:02:58 +0200, Antonio Quartulli wrote:
> On 03/09/2024 16:40, Sabrina Dubroca wrote:
> > 2024-08-27, 14:07:55 +0200, Antonio Quartulli wrote:
> > > static int ovpn_net_init(struct net_device *dev)
> > > {
> > > struct ovpn_struct *ovpn = netdev_priv(dev);
> > > + int i, err = gro_cells_init(&ovpn->gro_cells, dev);
> >
> > I'm not a fan of "hiding" the gro_cells_init call up here. I'd prefer
> > if this was done just before the corresponding "if (err)".
>
> I am all with you, but I remember in the past something complaining about
> "variable declared and then re-assigned right after".
>
> But maybe this is not the case anymore.
If you had something like:
int err;
err = -EINVAL;
sure, it would make sense to combine them.
>
> Will move the initialization down.
Thanks.
> > > +
> > > + spin_lock_init(&ovpn->peers->lock_by_id);
> > > + spin_lock_init(&ovpn->peers->lock_by_vpn_addr);
> > > + spin_lock_init(&ovpn->peers->lock_by_transp_addr);
> >
> > What's the benefit of having 3 separate locks instead of a single lock
> > protecting all the hashtables?
>
> The main reason was to avoid a deadlock - I thought I had added a comment
> about it...
Ok.
I could have missed it, I'm not looking at the comments much now that
I'm familiar with the code.
> The problem was a deadlock between acquiring peer->lock and
> ovpn->peers->lock in float() and in then opposite sequence in peers_free().
> (IIRC this happens due to ovpn_peer_reset_sockaddr() acquiring peer->lock)
I don't see a problem with ovpn_peer_reset_sockaddr, but ovpn_peer_put
can be called with lock_by_id held and then take peer->lock (in
ovpn_peer_release), which would be the opposite order to
ovpn_peer_float if the locks were merged (peer->lock then
lock_by_transp_addr).
This should be solvable with a single lock by delaying the bind
cleanup via call_rcu instead of doing it immediately with
ovpn_peer_release (after that delay, nothing should be using
peer->bind anymore, since we have no reference and no more
rcu_read_lock sections that could have found peer, so we can free
immediately and no need to take peer->lock). And it's I think a bit
more "correct" wrt RCU rules, since at ovpn_peer_put time, even with
refcount=0, we could have a reader still using the peer and deciding
to update its bind (not the case with how ovpn_peer_float is called,
since we have a reference on the peer).
(This could be completely wrong and/or make no sense at all :))
But I'm not going to insist on this, you can keep the separate locks.
> Splitting the larger peers->lock allowed me to avoid this scenario, because
> I don't need to jump through any hoop to coordinate access to different
> hashtables.
>
> >
> > > +
> > > + for (i = 0; i < ARRAY_SIZE(ovpn->peers->by_id); i++) {
> > > + INIT_HLIST_HEAD(&ovpn->peers->by_id[i]);
> > > + INIT_HLIST_HEAD(&ovpn->peers->by_vpn_addr[i]);
> > > + INIT_HLIST_NULLS_HEAD(&ovpn->peers->by_transp_addr[i],
> > > + i);
> > > + }
> > > + }
> > > +
> > > + return 0;
> > > }
> >
> > > +static int ovpn_peer_add_mp(struct ovpn_struct *ovpn, struct ovpn_peer *peer)
> > > +{
> > > + struct sockaddr_storage sa = { 0 };
> > > + struct hlist_nulls_head *nhead;
> > > + struct sockaddr_in6 *sa6;
> > > + struct sockaddr_in *sa4;
> > > + struct hlist_head *head;
> > > + struct ovpn_bind *bind;
> > > + struct ovpn_peer *tmp;
> > > + size_t salen;
> > > +
> > > + spin_lock_bh(&ovpn->peers->lock_by_id);
> > > + /* do not add duplicates */
> > > + tmp = ovpn_peer_get_by_id(ovpn, peer->id);
> > > + if (tmp) {
> > > + ovpn_peer_put(tmp);
> > > + spin_unlock_bh(&ovpn->peers->lock_by_id);
> > > + return -EEXIST;
> > > + }
> > > +
> > > + hlist_add_head_rcu(&peer->hash_entry_id,
> > > + ovpn_get_hash_head(ovpn->peers->by_id, &peer->id,
> > > + sizeof(peer->id)));
> > > + spin_unlock_bh(&ovpn->peers->lock_by_id);
> > > +
> > > + 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:
> >
> > And remove from the by_id hashtable? Or is that handled somewhere that
> > I missed (I don't think ovpn_peer_unhash gets called in that case)?
>
> No we don't call unhash in this case as we assume the adding just failed
> entirely.
>
> I will add the removal before returning the error (moving the add below the
> switch would extend the locked area too much.)
I don't think setting a few variables would be too much to do under
the lock (and it would address the issues in my 2nd reply to this
patch).
--
Sabrina
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 15/25] ovpn: implement multi-peer support
2024-09-05 10:47 ` Sabrina Dubroca
@ 2024-09-09 9:12 ` Antonio Quartulli
0 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-09 9:12 UTC (permalink / raw)
To: Sabrina Dubroca; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
On 05/09/2024 12:47, Sabrina Dubroca wrote:
>>>> +
>>>> + spin_lock_init(&ovpn->peers->lock_by_id);
>>>> + spin_lock_init(&ovpn->peers->lock_by_vpn_addr);
>>>> + spin_lock_init(&ovpn->peers->lock_by_transp_addr);
>>>
>>> What's the benefit of having 3 separate locks instead of a single lock
>>> protecting all the hashtables?
>>
>> The main reason was to avoid a deadlock - I thought I had added a comment
>> about it...
>
> Ok.
>
> I could have missed it, I'm not looking at the comments much now that
> I'm familiar with the code.
>
>> The problem was a deadlock between acquiring peer->lock and
>> ovpn->peers->lock in float() and in then opposite sequence in peers_free().
>> (IIRC this happens due to ovpn_peer_reset_sockaddr() acquiring peer->lock)
>
> I don't see a problem with ovpn_peer_reset_sockaddr, but ovpn_peer_put
> can be called with lock_by_id held and then take peer->lock (in
> ovpn_peer_release), which would be the opposite order to
> ovpn_peer_float if the locks were merged (peer->lock then
> lock_by_transp_addr).
>
> This should be solvable with a single lock by delaying the bind
> cleanup via call_rcu instead of doing it immediately with
> ovpn_peer_release (after that delay, nothing should be using
> peer->bind anymore, since we have no reference and no more
> rcu_read_lock sections that could have found peer, so we can free
> immediately and no need to take peer->lock). And it's I think a bit
> more "correct" wrt RCU rules, since at ovpn_peer_put time, even with
> refcount=0, we could have a reader still using the peer and deciding
> to update its bind (not the case with how ovpn_peer_float is called,
> since we have a reference on the peer).
Yap, I totally agree with your analysis.
In a previous version we simplified the code to the point that call_rcu
was not needed anymore and we could just rely on kfree_rcu for peer.
Now this "going back to call_rcu" felt a bit wrong, so I tried hard to
avoid that.
But I agree that actually this is a clear case where a two-steps release
is the right thing to do.
Will try to get it fixed as per your suggestion. Thanks!
>
> (This could be completely wrong and/or make no sense at all :))
>
> But I'm not going to insist on this, you can keep the separate locks.
>
>
>> Splitting the larger peers->lock allowed me to avoid this scenario, because
>> I don't need to jump through any hoop to coordinate access to different
>> hashtables.
>>
>>>
>>>> +
>>>> + for (i = 0; i < ARRAY_SIZE(ovpn->peers->by_id); i++) {
>>>> + INIT_HLIST_HEAD(&ovpn->peers->by_id[i]);
>>>> + INIT_HLIST_HEAD(&ovpn->peers->by_vpn_addr[i]);
>>>> + INIT_HLIST_NULLS_HEAD(&ovpn->peers->by_transp_addr[i],
>>>> + i);
>>>> + }
>>>> + }
>>>> +
>>>> + return 0;
>>>> }
>>>
>>>> +static int ovpn_peer_add_mp(struct ovpn_struct *ovpn, struct ovpn_peer *peer)
>>>> +{
>>>> + struct sockaddr_storage sa = { 0 };
>>>> + struct hlist_nulls_head *nhead;
>>>> + struct sockaddr_in6 *sa6;
>>>> + struct sockaddr_in *sa4;
>>>> + struct hlist_head *head;
>>>> + struct ovpn_bind *bind;
>>>> + struct ovpn_peer *tmp;
>>>> + size_t salen;
>>>> +
>>>> + spin_lock_bh(&ovpn->peers->lock_by_id);
>>>> + /* do not add duplicates */
>>>> + tmp = ovpn_peer_get_by_id(ovpn, peer->id);
>>>> + if (tmp) {
>>>> + ovpn_peer_put(tmp);
>>>> + spin_unlock_bh(&ovpn->peers->lock_by_id);
>>>> + return -EEXIST;
>>>> + }
>>>> +
>>>> + hlist_add_head_rcu(&peer->hash_entry_id,
>>>> + ovpn_get_hash_head(ovpn->peers->by_id, &peer->id,
>>>> + sizeof(peer->id)));
>>>> + spin_unlock_bh(&ovpn->peers->lock_by_id);
>>>> +
>>>> + 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:
>>>
>>> And remove from the by_id hashtable? Or is that handled somewhere that
>>> I missed (I don't think ovpn_peer_unhash gets called in that case)?
>>
>> No we don't call unhash in this case as we assume the adding just failed
>> entirely.
>>
>> I will add the removal before returning the error (moving the add below the
>> switch would extend the locked area too much.)
>
> I don't think setting a few variables would be too much to do under
> the lock (and it would address the issues in my 2nd reply to this
> patch).
Right - pretty much what I replied to that comment (will move the add
after the bind dereference)
Cheers,
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread
* [PATCH net-next v6 16/25] ovpn: implement peer lookup logic
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (14 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 15/25] ovpn: implement multi-peer support Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 17/25] ovpn: implement keepalive mechanism Antonio Quartulli
` (8 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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 | 270 ++++++++++++++++++++++++++++++++++++++--
1 file changed, 262 insertions(+), 8 deletions(-)
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 58037c2cbcca..1225032e605c 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 "ovpnstruct.h"
#include "bind.h"
@@ -126,6 +127,92 @@ static bool ovpn_peer_skb_to_sockaddr(struct sk_buff *skb,
return true;
}
+/**
+ * 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;
+}
+
+#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \
+ typeof(_tbl) *__tbl = &(_tbl); \
+ (&(*__tbl)[jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl)]); }) \
+
+/**
+ * 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_struct *ovpn,
+ __be32 addr)
+{
+ struct hlist_head *head;
+ struct ovpn_peer *tmp;
+
+ head = ovpn_get_hash_head(ovpn->peers->by_vpn_addr, &addr,
+ sizeof(addr));
+
+ hlist_for_each_entry_rcu(tmp, head, hash_entry_addr4)
+ if (addr == tmp->vpn_addrs.ipv4.s_addr)
+ return tmp;
+
+ 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_struct *ovpn,
+ struct in6_addr *addr)
+{
+ struct hlist_head *head;
+ struct ovpn_peer *tmp;
+
+ head = ovpn_get_hash_head(ovpn->peers->by_vpn_addr, addr,
+ sizeof(*addr));
+
+ hlist_for_each_entry_rcu(tmp, head, hash_entry_addr6)
+ if (ipv6_addr_equal(addr, &tmp->vpn_addrs.ipv6))
+ return tmp;
+
+ return NULL;
+}
+
/**
* ovpn_peer_transp_match - check if sockaddr and peer binding match
* @peer: the peer to get the binding from
@@ -203,14 +290,44 @@ ovpn_peer_get_by_transp_addr_p2p(struct ovpn_struct *ovpn,
struct ovpn_peer *ovpn_peer_get_by_transp_addr(struct ovpn_struct *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;
+ size_t sa_len;
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 ovpn_peer_get_by_transp_addr_p2p(ovpn, &ss);
+
+ switch (ss.ss_family) {
+ case AF_INET:
+ sa_len = sizeof(struct sockaddr_in);
+ break;
+ case AF_INET6:
+ sa_len = sizeof(struct sockaddr_in6);
+ break;
+ default:
+ return NULL;
+ }
+
+ nhead = ovpn_get_hash_head(ovpn->peers->by_transp_addr, &ss, sa_len);
+
+ rcu_read_lock();
+ 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;
+ }
+ rcu_read_unlock();
return peer;
}
@@ -245,10 +362,27 @@ static struct ovpn_peer *ovpn_peer_get_by_id_p2p(struct ovpn_struct *ovpn,
*/
struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_struct *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;
}
@@ -270,6 +404,8 @@ struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_struct *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
@@ -280,11 +416,109 @@ struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_struct *ovpn,
if (unlikely(peer && !ovpn_peer_hold(peer)))
peer = NULL;
rcu_read_unlock();
+ return peer;
}
+ rcu_read_lock();
+ switch (skb_protocol_to_family(skb)) {
+ case AF_INET:
+ addr4 = ovpn_nexthop_from_skb4(skb);
+ peer = ovpn_peer_get_by_vpn_addr4(ovpn, addr4);
+ break;
+ case AF_INET6:
+ 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_struct *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", __func__,
+ &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_struct *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", __func__,
+ &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
@@ -297,6 +531,8 @@ bool ovpn_peer_check_by_src(struct ovpn_struct *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
@@ -305,15 +541,33 @@ bool ovpn_peer_check_by_src(struct ovpn_struct *ovpn, struct sk_buff *skb,
rcu_read_lock();
match = (peer == rcu_dereference(ovpn->peer));
rcu_read_unlock();
+ return match;
+ }
+
+ /* 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_to_family(skb)) {
+ case AF_INET:
+ 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 AF_INET6:
+ 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
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 17/25] ovpn: implement keepalive mechanism
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (15 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 16/25] ovpn: implement peer lookup logic Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-09-03 15:17 ` Sabrina Dubroca
2024-08-27 12:07 ` [PATCH net-next v6 18/25] ovpn: add support for updating local UDP endpoint Antonio Quartulli
` (7 subsequent siblings)
24 siblings, 1 reply; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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 | 77 ++++++++++++++
drivers/net/ovpn/io.h | 5 +
drivers/net/ovpn/main.c | 3 +
drivers/net/ovpn/ovpnstruct.h | 2 +
drivers/net/ovpn/peer.c | 186 ++++++++++++++++++++++++++++++++++
drivers/net/ovpn/peer.h | 15 +++
drivers/net/ovpn/proto.h | 2 -
7 files changed, 288 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index cde1c8ce5cf5..60b47350d841 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -25,6 +25,33 @@
#include "udp.h"
#include "skb.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.
*/
@@ -88,6 +115,9 @@ void ovpn_decrypt_post(struct sk_buff *skb, int ret)
goto drop;
}
+ /* keep track of last received authenticated packet for keepalive */
+ peer->last_recv = ktime_get_real_seconds();
+
/* point to encapsulated IP packet */
__skb_pull(skb, ovpn_skb_cb(skb)->ctx->payload_offset);
@@ -104,6 +134,12 @@ void ovpn_decrypt_post(struct sk_buff *skb, int ret)
goto drop;
}
+ if (ovpn_is_keepalive(skb)) {
+ net_dbg_ratelimited("%s: ping received from peer %u\n",
+ peer->ovpn->dev->name, peer->id);
+ goto drop;
+ }
+
net_info_ratelimited("%s: unsupported protocol received from peer %u\n",
peer->ovpn->dev->name, peer->id);
goto drop;
@@ -194,6 +230,10 @@ void ovpn_encrypt_post(struct sk_buff *skb, int ret)
/* no transport configured yet */
goto err;
}
+
+ /* keep track of last sent packet for keepalive */
+ peer->last_sent = ktime_get_real_seconds();
+
/* skb passed down the stack - don't free it */
skb = NULL;
err:
@@ -338,3 +378,40 @@ 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
+ */
+void ovpn_xmit_special(struct ovpn_peer *peer, const void *data,
+ const unsigned int len)
+{
+ struct ovpn_struct *ovpn;
+ struct sk_buff *skb;
+
+ ovpn = peer->ovpn;
+ if (unlikely(!ovpn))
+ return;
+
+ skb = alloc_skb(256 + len, GFP_ATOMIC);
+ if (unlikely(!skb))
+ return;
+
+ skb_reserve(skb, 128);
+ skb->priority = TC_PRIO_BESTEFFORT;
+ __skb_put_data(skb, data, len);
+
+ /* increase reference counter when passing peer to sending queue */
+ if (!ovpn_peer_hold(peer)) {
+ netdev_dbg(ovpn->dev, "%s: cannot hold peer reference for sending special packet\n",
+ __func__);
+ kfree_skb(skb);
+ return;
+ }
+
+ ovpn_send(ovpn, skb, peer);
+}
diff --git a/drivers/net/ovpn/io.h b/drivers/net/ovpn/io.h
index ad741552d742..7eae8d1b368d 100644
--- a/drivers/net/ovpn/io.h
+++ b/drivers/net/ovpn/io.h
@@ -10,9 +10,14 @@
#ifndef _NET_OVPN_OVPN_H_
#define _NET_OVPN_OVPN_H_
+#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(struct sk_buff *skb, int ret);
void ovpn_decrypt_post(struct sk_buff *skb, int ret);
diff --git a/drivers/net/ovpn/main.c b/drivers/net/ovpn/main.c
index 94d2ee87807f..0f9d79a05f4f 100644
--- a/drivers/net/ovpn/main.c
+++ b/drivers/net/ovpn/main.c
@@ -45,6 +45,7 @@ static int ovpn_struct_init(struct net_device *dev, enum ovpn_mode mode)
ovpn->dev = dev;
ovpn->mode = mode;
spin_lock_init(&ovpn->lock);
+ INIT_DELAYED_WORK(&ovpn->keepalive_work, ovpn_peer_keepalive_work);
return 0;
}
@@ -249,6 +250,8 @@ void ovpn_iface_destruct(struct ovpn_struct *ovpn)
ovpn->registered = false;
+ cancel_delayed_work_sync(&ovpn->keepalive_work);
+
switch (ovpn->mode) {
case OVPN_MODE_P2P:
ovpn_peer_release_p2p(ovpn);
diff --git a/drivers/net/ovpn/ovpnstruct.h b/drivers/net/ovpn/ovpnstruct.h
index 3d74e79fcdf3..0fdc6ab77eaa 100644
--- a/drivers/net/ovpn/ovpnstruct.h
+++ b/drivers/net/ovpn/ovpnstruct.h
@@ -45,6 +45,7 @@ struct ovpn_peer_collection {
* @peer: in P2P mode, this is the only remote peer
* @dev_list: entry for the module wide device list
* @gro_cells: pointer to the Generic Receive Offload cell
+ * @keepalive_work: struct used to schedule keepalive periodic job
*/
struct ovpn_struct {
struct net_device *dev;
@@ -56,6 +57,7 @@ struct ovpn_struct {
struct ovpn_peer __rcu *peer;
struct list_head dev_list;
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 1225032e605c..a3f4f3231f3b 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -22,6 +22,34 @@
#include "peer.h"
#include "socket.h"
+/**
+ * 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,
+ "%s: scheduling keepalive for peer %u: interval=%u timeout=%u\n",
+ __func__, peer->id, interval, timeout);
+
+ peer->keepalive_interval = interval;
+ peer->last_sent = now;
+ peer->keepalive_xmit_exp = now + interval;
+
+ peer->keepalive_timeout = timeout;
+ 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_new - allocate and initialize a new peer object
* @ovpn: the openvpn instance inside which the peer should be created
@@ -77,6 +105,7 @@ static void ovpn_peer_release(struct ovpn_peer *peer)
ovpn_crypto_state_release(&peer->crypto);
ovpn_bind_reset(peer, NULL);
+
dst_cache_destroy(&peer->dst_cache);
}
@@ -822,6 +851,19 @@ int ovpn_peer_del(struct ovpn_peer *peer, enum ovpn_del_peer_reason reason)
}
}
+static int ovpn_peer_del_nolock(struct ovpn_peer *peer,
+ enum ovpn_del_peer_reason reason)
+{
+ switch (peer->ovpn->mode) {
+ case OVPN_MODE_MP:
+ return ovpn_peer_del_mp(peer, reason);
+ case OVPN_MODE_P2P:
+ return ovpn_peer_del_p2p(peer, reason);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
/**
* ovpn_peers_free - free all peers in the instance
* @ovpn: the instance whose peers should be released
@@ -837,3 +879,147 @@ void ovpn_peers_free(struct ovpn_struct *ovpn)
ovpn_peer_unhash(peer, OVPN_DEL_PEER_REASON_TEARDOWN);
spin_unlock_bh(&ovpn->peers->lock_by_id);
}
+
+static time64_t ovpn_peer_keepalive_work_single(struct ovpn_peer *peer,
+ time64_t now)
+{
+ time64_t next_run1, next_run2, delta;
+ 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;
+ delta = now - peer->last_recv;
+ if (delta < timeout) {
+ peer->keepalive_recv_exp = now + timeout - delta;
+ 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_del_nolock(peer, OVPN_DEL_PEER_REASON_EXPIRED);
+ return 0;
+ }
+
+ /* check for peer keepalive */
+ expired = false;
+ interval = peer->keepalive_interval;
+ delta = now - peer->last_sent;
+ if (delta < interval) {
+ peer->keepalive_xmit_exp = now + interval - delta;
+ 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);
+ ovpn_xmit_special(peer, ovpn_keepalive_message,
+ sizeof(ovpn_keepalive_message));
+ }
+
+ if (next_run1 < next_run2)
+ return next_run1;
+
+ return next_run2;
+}
+
+static time64_t ovpn_peer_keepalive_work_mp(struct ovpn_struct *ovpn,
+ time64_t now)
+{
+ time64_t tmp_next_run, next_run = 0;
+ struct hlist_node *tmp;
+ struct ovpn_peer *peer;
+ int bkt;
+
+ spin_lock_bh(&ovpn->peers->lock_by_id);
+ hash_for_each_safe(ovpn->peers->by_id, bkt, tmp, peer, hash_entry_id) {
+ tmp_next_run = ovpn_peer_keepalive_work_single(peer, now);
+
+ /* 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;
+ }
+ spin_unlock_bh(&ovpn->peers->lock_by_id);
+
+ return next_run;
+}
+
+static time64_t ovpn_peer_keepalive_work_p2p(struct ovpn_struct *ovpn,
+ time64_t now)
+{
+ struct ovpn_peer *peer;
+ time64_t next_run;
+
+ spin_lock_bh(&ovpn->lock);
+ peer = rcu_dereference_protected(ovpn->peer,
+ lockdep_is_held(&ovpn->lock));
+ next_run = ovpn_peer_keepalive_work_single(peer, now);
+ spin_unlock_bh(&ovpn->lock);
+
+ 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_struct *ovpn = container_of(work, struct ovpn_struct,
+ keepalive_work.work);
+ time64_t next_run = 0, now = ktime_get_real_seconds();
+
+ switch (ovpn->mode) {
+ case OVPN_MODE_MP:
+ next_run = ovpn_peer_keepalive_work_mp(ovpn, now);
+ break;
+ case OVPN_MODE_P2P:
+ next_run = ovpn_peer_keepalive_work_p2p(ovpn, now);
+ 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);
+ }
+}
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index dc51cc93ef20..b632fabf9524 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -50,6 +50,12 @@
* @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
* @halt: true if ovpn_peer_mark_delete was called
* @vpn_stats: per-peer in-VPN TX/RX stays
* @link_stats: per-peer link/transport TX/RX stats
@@ -98,6 +104,12 @@ 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;
bool halt;
struct ovpn_peer_stats vpn_stats;
struct ovpn_peer_stats link_stats;
@@ -144,4 +156,7 @@ struct ovpn_peer *ovpn_peer_get_by_dst(struct ovpn_struct *ovpn,
bool ovpn_peer_check_by_src(struct ovpn_struct *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_ */
diff --git a/drivers/net/ovpn/proto.h b/drivers/net/ovpn/proto.h
index 32af6b8e5743..0de8bafadc89 100644
--- a/drivers/net/ovpn/proto.h
+++ b/drivers/net/ovpn/proto.h
@@ -35,8 +35,6 @@
#define OVPN_OP_SIZE_V2 4
#define OVPN_PEER_ID_MASK 0x00FFFFFF
#define OVPN_PEER_ID_UNDEF 0x00FFFFFF
-/* first byte of keepalive message */
-#define OVPN_KEEPALIVE_FIRST_BYTE 0x2a
/* first byte of exit message */
#define OVPN_EXPLICIT_EXIT_NOTIFY_FIRST_BYTE 0x28
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 17/25] ovpn: implement keepalive mechanism
2024-08-27 12:07 ` [PATCH net-next v6 17/25] ovpn: implement keepalive mechanism Antonio Quartulli
@ 2024-09-03 15:17 ` Sabrina Dubroca
2024-09-09 9:17 ` Antonio Quartulli
0 siblings, 1 reply; 58+ messages in thread
From: Sabrina Dubroca @ 2024-09-03 15:17 UTC (permalink / raw)
To: Antonio Quartulli; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
2024-08-27, 14:07:57 +0200, Antonio Quartulli wrote:
> +static time64_t ovpn_peer_keepalive_work_mp(struct ovpn_struct *ovpn,
> + time64_t now)
> +{
> + time64_t tmp_next_run, next_run = 0;
> + struct hlist_node *tmp;
> + struct ovpn_peer *peer;
> + int bkt;
> +
> + spin_lock_bh(&ovpn->peers->lock_by_id);
> + hash_for_each_safe(ovpn->peers->by_id, bkt, tmp, peer, hash_entry_id) {
> + tmp_next_run = ovpn_peer_keepalive_work_single(peer, now);
> +
> + /* the next worker run will be scheduled based on the shortest
> + * required interval across all peers
> + */
> + if (!next_run || tmp_next_run < next_run)
I think this should exclude tmp_next_run == 0.
If we have two peers, with the first getting a non-0 value and the 2nd
getting 0, we'll end up with next_run = 0 on return.
If we have three peers and ovpn_peer_keepalive_work_single returns
12,0,42, we'll end up with 42 (after resetting to 0 on the 2nd peer),
and we could miss sending the needed keepalive for peer 1.
> + next_run = tmp_next_run;
> + }
> + spin_unlock_bh(&ovpn->peers->lock_by_id);
> +
> + return next_run;
> +}
--
Sabrina
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 17/25] ovpn: implement keepalive mechanism
2024-09-03 15:17 ` Sabrina Dubroca
@ 2024-09-09 9:17 ` Antonio Quartulli
0 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-09 9:17 UTC (permalink / raw)
To: Sabrina Dubroca; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
Hi,
On 03/09/2024 17:17, Sabrina Dubroca wrote:
> 2024-08-27, 14:07:57 +0200, Antonio Quartulli wrote:
>> +static time64_t ovpn_peer_keepalive_work_mp(struct ovpn_struct *ovpn,
>> + time64_t now)
>> +{
>> + time64_t tmp_next_run, next_run = 0;
>> + struct hlist_node *tmp;
>> + struct ovpn_peer *peer;
>> + int bkt;
>> +
>> + spin_lock_bh(&ovpn->peers->lock_by_id);
>> + hash_for_each_safe(ovpn->peers->by_id, bkt, tmp, peer, hash_entry_id) {
>> + tmp_next_run = ovpn_peer_keepalive_work_single(peer, now);
>> +
>> + /* the next worker run will be scheduled based on the shortest
>> + * required interval across all peers
>> + */
>> + if (!next_run || tmp_next_run < next_run)
>
> I think this should exclude tmp_next_run == 0.
or, for better clarity of the flow, I will add:
if (!tmp_next_run)
continue;
since 0 explicitly means "keepalive disabled" or "no keepalive needed
for $reasons".
>
> If we have two peers, with the first getting a non-0 value and the 2nd
> getting 0, we'll end up with next_run = 0 on return.
>
> If we have three peers and ovpn_peer_keepalive_work_single returns
> 12,0,42, we'll end up with 42 (after resetting to 0 on the 2nd peer),
> and we could miss sending the needed keepalive for peer 1.
>
Absolutely. Thanks for pointing this out!
Cheers,
>> + next_run = tmp_next_run;
>> + }
>> + spin_unlock_bh(&ovpn->peers->lock_by_id);
>> +
>> + return next_run;
>> +}
>
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread
* [PATCH net-next v6 18/25] ovpn: add support for updating local UDP endpoint
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (16 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 17/25] ovpn: implement keepalive mechanism Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-08-27 12:07 ` [PATCH net-next v6 19/25] ovpn: add support for peer floating Antonio Quartulli
` (6 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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 a3f4f3231f3b..63e3e83b4fa5 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -416,6 +416,51 @@ struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_struct *ovpn, u32 peer_id)
return peer;
}
+/**
+ * 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_to_family(skb)) {
+ case AF_INET:
+ if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) {
+ netdev_dbg(peer->ovpn->dev,
+ "%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n",
+ __func__, peer->id, &bind->local.ipv4.s_addr,
+ &ip_hdr(skb)->daddr);
+ bind->local.ipv4.s_addr = ip_hdr(skb)->daddr;
+ }
+ break;
+ case AF_INET6:
+ if (unlikely(!ipv6_addr_equal(&bind->local.ipv6,
+ &ipv6_hdr(skb)->daddr))) {
+ netdev_dbg(peer->ovpn->dev,
+ "%s: learning local IPv6 for peer %d (%pI6c -> %pI6c\n",
+ __func__, 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 b632fabf9524..2b1b0ad3d309 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -159,4 +159,7 @@ bool ovpn_peer_check_by_src(struct ovpn_struct *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_ */
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 19/25] ovpn: add support for peer floating
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (17 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 18/25] ovpn: add support for updating local UDP endpoint Antonio Quartulli
@ 2024-08-27 12:07 ` Antonio Quartulli
2024-09-05 9:55 ` Sabrina Dubroca
2024-08-27 12:08 ` [PATCH net-next v6 20/25] ovpn: implement peer add/dump/delete via netlink Antonio Quartulli
` (5 subsequent siblings)
24 siblings, 1 reply; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:07 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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/bind.c | 10 +---
drivers/net/ovpn/io.c | 9 +++
drivers/net/ovpn/peer.c | 123 ++++++++++++++++++++++++++++++++++++++--
drivers/net/ovpn/peer.h | 2 +
4 files changed, 133 insertions(+), 11 deletions(-)
diff --git a/drivers/net/ovpn/bind.c b/drivers/net/ovpn/bind.c
index b4d2ccec2ced..d17d078c5730 100644
--- a/drivers/net/ovpn/bind.c
+++ b/drivers/net/ovpn/bind.c
@@ -47,12 +47,8 @@ struct ovpn_bind *ovpn_bind_from_sockaddr(const struct sockaddr_storage *ss)
* @new: the new bind to assign
*/
void ovpn_bind_reset(struct ovpn_peer *peer, struct ovpn_bind *new)
+ __must_hold(&peer->lock)
{
- 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);
+ kfree_rcu(rcu_replace_pointer(peer->bind, new,
+ lockdep_is_held(&peer->lock)), rcu);
}
diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index 60b47350d841..28dab793de63 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -118,6 +118,15 @@ void ovpn_decrypt_post(struct sk_buff *skb, int ret)
/* keep track of last received authenticated packet for keepalive */
peer->last_recv = ktime_get_real_seconds();
+ if (peer->sock->sock->sk->sk_protocol == IPPROTO_UDP) {
+ /* check if this peer changed it's IP address and update
+ * state
+ */
+ ovpn_peer_float(peer, skb);
+ /* update source endpoint for this peer */
+ ovpn_peer_update_local_endpoint(peer, skb);
+ }
+
/* point to encapsulated IP packet */
__skb_pull(skb, ovpn_skb_cb(skb)->ctx->payload_offset);
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 63e3e83b4fa5..452fb9e521e4 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -94,6 +94,123 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_struct *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)
+ __must_hold(&peer->lock)
+{
+ struct ovpn_bind *bind;
+ size_t ip_len;
+
+ /* 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 {
+ netdev_dbg(peer->ovpn->dev, "%s: invalid family for remote endpoint\n",
+ __func__);
+ kfree(bind);
+ return -EINVAL;
+ }
+
+ memcpy(&bind->local, local_ip, ip_len);
+ }
+
+ /* set binding */
+ ovpn_bind_reset(peer, bind);
+
+ return 0;
+}
+
+#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \
+ typeof(_tbl) *__tbl = &(_tbl); \
+ (&(*__tbl)[jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl)]); }) \
+
+/**
+ * ovpn_peer_float - update remote endpoint for peer
+ * @peer: peer to update the remote endpoint for
+ * @skb: incoming packet to retrieve the source address (remote) from
+ */
+void ovpn_peer_float(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;
+ sa_family_t family;
+ size_t salen;
+
+ rcu_read_lock();
+ bind = rcu_dereference(peer->bind);
+ if (unlikely(!bind)) {
+ rcu_read_unlock();
+ return;
+ }
+
+ spin_lock_bh(&peer->lock);
+ if (likely(ovpn_bind_skb_src_match(bind, skb)))
+ goto unlock;
+
+ family = skb_protocol_to_family(skb);
+
+ if (bind->remote.in4.sin_family == family)
+ local_ip = (u8 *)&bind->local;
+
+ switch (family) {
+ case AF_INET:
+ 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;
+ case AF_INET6:
+ 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);
+ break;
+ default:
+ goto unlock;
+ }
+
+ netdev_dbg(peer->ovpn->dev, "%s: peer %d floated to %pIScp", __func__,
+ peer->id, &ss);
+ ovpn_peer_reset_sockaddr(peer, (struct sockaddr_storage *)&ss,
+ local_ip);
+
+ spin_lock_bh(&peer->ovpn->peers->lock_by_transp_addr);
+ /* 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, &ss,
+ salen);
+ hlist_nulls_add_head_rcu(&peer->hash_entry_transp_addr, nhead);
+ spin_unlock_bh(&peer->ovpn->peers->lock_by_transp_addr);
+unlock:
+ spin_unlock_bh(&peer->lock);
+ rcu_read_unlock();
+}
+
/**
* ovpn_peer_release - release peer private members
* @peer: the peer to release
@@ -104,7 +221,9 @@ static void ovpn_peer_release(struct ovpn_peer *peer)
ovpn_socket_put(peer->sock);
ovpn_crypto_state_release(&peer->crypto);
+ spin_lock_bh(&peer->lock);
ovpn_bind_reset(peer, NULL);
+ spin_unlock_bh(&peer->lock);
dst_cache_destroy(&peer->dst_cache);
}
@@ -188,10 +307,6 @@ static struct in6_addr ovpn_nexthop_from_skb6(struct sk_buff *skb)
return rt->rt6i_gateway;
}
-#define ovpn_get_hash_head(_tbl, _key, _key_len) ({ \
- typeof(_tbl) *__tbl = &(_tbl); \
- (&(*__tbl)[jhash(_key, _key_len, 0) % HASH_SIZE(*__tbl)]); }) \
-
/**
* ovpn_peer_get_by_vpn_addr4 - retrieve peer by its VPN IPv4 address
* @ovpn: the openvpn instance to search
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index 2b1b0ad3d309..187e7d840705 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -162,4 +162,6 @@ 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_float(struct ovpn_peer *peer, struct sk_buff *skb);
+
#endif /* _NET_OVPN_OVPNPEER_H_ */
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 19/25] ovpn: add support for peer floating
2024-08-27 12:07 ` [PATCH net-next v6 19/25] ovpn: add support for peer floating Antonio Quartulli
@ 2024-09-05 9:55 ` Sabrina Dubroca
2024-09-09 8:52 ` Antonio Quartulli
0 siblings, 1 reply; 58+ messages in thread
From: Sabrina Dubroca @ 2024-09-05 9:55 UTC (permalink / raw)
To: Antonio Quartulli; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
2024-08-27, 14:07:59 +0200, Antonio Quartulli wrote:
> +void ovpn_peer_float(struct ovpn_peer *peer, struct sk_buff *skb)
> +{
[...]
> +
> + netdev_dbg(peer->ovpn->dev, "%s: peer %d floated to %pIScp", __func__,
> + peer->id, &ss);
> + ovpn_peer_reset_sockaddr(peer, (struct sockaddr_storage *)&ss,
> + local_ip);
> +
> + spin_lock_bh(&peer->ovpn->peers->lock_by_transp_addr);
ovpn->peers in only set in MP mode, is there something preventing us
getting here in P2P mode? I think we need a mode==MP check around the
rehash. (I just took a look at other uses of ovpn->peers and there
are obvious mode == MP checks before all of them except this one)
I guess this would only happen in P2P mode if the server changes IP,
so it doesn't really occur in practice?
--
Sabrina
^ permalink raw reply [flat|nested] 58+ messages in thread* Re: [PATCH net-next v6 19/25] ovpn: add support for peer floating
2024-09-05 9:55 ` Sabrina Dubroca
@ 2024-09-09 8:52 ` Antonio Quartulli
0 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-09-09 8:52 UTC (permalink / raw)
To: Sabrina Dubroca; +Cc: netdev, kuba, pabeni, ryazanov.s.a, edumazet, andrew
On 05/09/2024 11:55, Sabrina Dubroca wrote:
> 2024-08-27, 14:07:59 +0200, Antonio Quartulli wrote:
>> +void ovpn_peer_float(struct ovpn_peer *peer, struct sk_buff *skb)
>> +{
> [...]
>> +
>> + netdev_dbg(peer->ovpn->dev, "%s: peer %d floated to %pIScp", __func__,
>> + peer->id, &ss);
>> + ovpn_peer_reset_sockaddr(peer, (struct sockaddr_storage *)&ss,
>> + local_ip);
>> +
>> + spin_lock_bh(&peer->ovpn->peers->lock_by_transp_addr);
>
> ovpn->peers in only set in MP mode, is there something preventing us
> getting here in P2P mode? I think we need a mode==MP check around the
> rehash. (I just took a look at other uses of ovpn->peers and there
> are obvious mode == MP checks before all of them except this one)
>
> I guess this would only happen in P2P mode if the server changes IP,
> so it doesn't really occur in practice?
Good point. Technically this is still possible (a server may change IP
or we may be connected against another P2P host that changes IP),
therefore we should not prevent float from working properly in P2P.
I will fix this in the next version.
Thanks!
--
Antonio Quartulli
OpenVPN Inc.
^ permalink raw reply [flat|nested] 58+ messages in thread
* [PATCH net-next v6 20/25] ovpn: implement peer add/dump/delete via netlink
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (18 preceding siblings ...)
2024-08-27 12:07 ` [PATCH net-next v6 19/25] ovpn: add support for peer floating Antonio Quartulli
@ 2024-08-27 12:08 ` Antonio Quartulli
2024-08-27 12:08 ` [PATCH net-next v6 21/25] ovpn: implement key add/del/swap " Antonio Quartulli
` (4 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:08 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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 | 519 ++++++++++++++++++++++++++++++++++++-
drivers/net/ovpn/peer.c | 11 +-
drivers/net/ovpn/peer.h | 4 +
3 files changed, 525 insertions(+), 9 deletions(-)
diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c
index daa2f1ec46dc..9c9ad1e4cb9a 100644
--- a/drivers/net/ovpn/netlink.c
+++ b/drivers/net/ovpn/netlink.c
@@ -8,6 +8,7 @@
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
+#include <linux/types.h>
#include <net/genetlink.h>
#include <uapi/linux/ovpn.h>
@@ -17,6 +18,10 @@
#include "io.h"
#include "netlink.h"
#include "netlink-gen.h"
+#include "bind.h"
+#include "packet.h"
+#include "peer.h"
+#include "socket.h"
MODULE_ALIAS_GENL_FAMILY(OVPN_FAMILY_NAME);
@@ -147,24 +152,530 @@ int ovpn_nl_del_iface_doit(struct sk_buff *skb, struct genl_info *info)
return 0;
}
+static u8 *ovpn_nl_attr_local_ip(struct genl_info *info,
+ struct ovpn_struct *ovpn,
+ struct nlattr **attrs, int sock_fam)
+{
+ size_t ip_len = nla_len(attrs[OVPN_A_PEER_LOCAL_IP]);
+ u8 *local_ip = nla_data(attrs[OVPN_A_PEER_LOCAL_IP]);
+ bool is_mapped;
+
+ if (ip_len == sizeof(struct in_addr)) {
+ if (sock_fam != AF_INET) {
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "mismatching AF between local IP (v4) and peer");
+ return ERR_PTR(-EINVAL);
+ }
+ } else if (ip_len == sizeof(struct in6_addr)) {
+ is_mapped = ipv6_addr_v4mapped((struct in6_addr *)local_ip);
+
+ if (sock_fam != AF_INET6 && !is_mapped) {
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "mismatching AF between local IP (v6) and peer");
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (is_mapped)
+ /* this is an IPv6-mapped IPv4
+ * address, therefore extract
+ * the actual v4 address from
+ * the last 4 bytes
+ */
+ local_ip += 12;
+ } else {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "invalid local IP length: %zu", ip_len);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return local_ip;
+}
+
int ovpn_nl_set_peer_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct nlattr *attrs[OVPN_A_PEER_MAX + 1];
+ struct ovpn_struct *ovpn = info->user_ptr[0];
+ struct sockaddr_storage *ss = NULL;
+ u32 sockfd, id, interv, timeout;
+ struct socket *sock = NULL;
+ struct sockaddr_in mapped;
+ struct sockaddr_in6 *in6;
+ struct ovpn_peer *peer;
+ bool new_peer = false;
+ u8 *local_ip = NULL;
+ size_t sa_len;
+ 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;
+
+ id = nla_get_u32(attrs[OVPN_A_PEER_ID]);
+ /* check if the peer exists first, otherwise create a new one */
+ peer = ovpn_peer_get_by_id(ovpn, id);
+ if (!peer) {
+ if (NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_PEER],
+ attrs, OVPN_A_PEER_SOCKET))
+ return -EINVAL;
+
+ if (ovpn->mode == OVPN_MODE_MP &&
+ !attrs[OVPN_A_PEER_VPN_IPV4] &&
+ !attrs[OVPN_A_PEER_VPN_IPV6]) {
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "a VPN IP is required when adding a peer in MP mode");
+ return -EINVAL;
+ }
+
+ peer = ovpn_peer_new(ovpn, id);
+ new_peer = true;
+ if (IS_ERR(peer)) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "cannot create new peer object for peer %u: %ld",
+ id, PTR_ERR(peer));
+ return PTR_ERR(peer);
+ }
+ }
+
+ /* VPN IPs cannot be updated, because they are hashed */
+ if (!new_peer && (attrs[OVPN_A_PEER_VPN_IPV4] ||
+ attrs[OVPN_A_PEER_VPN_IPV6])) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "VPN IPs cannot be updated");
+ ret = -EINVAL;
+ goto peer_release;
+ }
+
+ /* 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,
+ "VPN IP unexpected in P2P mode");
+ ret = -EINVAL;
+ goto peer_release;
+ }
+
+ 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");
+ ret = -EINVAL;
+ goto peer_release;
+ }
+
+ if (attrs[OVPN_A_PEER_SOCKET]) {
+ /* 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.
+ *
+ * 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_UDP &&
+ attrs[OVPN_A_PEER_SOCKADDR_REMOTE]) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "unexpected sockaddr remote for non UDP socket");
+ sockfd_put(sock);
+ ret = -EINVAL;
+ goto peer_release;
+ }
+
+ if (peer->sock)
+ ovpn_socket_put(peer->sock);
+
+ peer->sock = ovpn_socket_new(sock, peer);
+ if (IS_ERR(peer->sock)) {
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "cannot encapsulate socket: %ld",
+ PTR_ERR(peer->sock));
+ sockfd_put(sock);
+ peer->sock = NULL;
+ ret = -ENOTSOCK;
+ goto peer_release;
+ }
+ }
+
+ if (attrs[OVPN_A_PEER_SOCKADDR_REMOTE]) {
+ ss = nla_data(attrs[OVPN_A_PEER_SOCKADDR_REMOTE]);
+ sa_len = nla_len(attrs[OVPN_A_PEER_SOCKADDR_REMOTE]);
+ switch (sa_len) {
+ case sizeof(struct sockaddr_in):
+ if (ss->ss_family == AF_INET)
+ /* valid sockaddr */
+ break;
+
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "remote sockaddr_in has invalid family");
+ ret = -EINVAL;
+ goto peer_release;
+ case sizeof(struct sockaddr_in6):
+ if (ss->ss_family == AF_INET6)
+ /* valid sockaddr */
+ break;
+
+ NL_SET_ERR_MSG_MOD(info->extack,
+ "remote sockaddr_in6 has invalid family");
+ ret = -EINVAL;
+ goto peer_release;
+ default:
+ NL_SET_ERR_MSG_FMT_MOD(info->extack,
+ "invalid size for sockaddr: %zd",
+ sa_len);
+ ret = -EINVAL;
+ goto peer_release;
+ }
+
+ /* if this is a v6-mapped-v4, convert the sockaddr
+ * object from AF_INET6 to AF_INET before continue
+ * processing
+ */
+ if (ss->ss_family == AF_INET6) {
+ in6 = (struct sockaddr_in6 *)ss;
+
+ if (ipv6_addr_v4mapped(&in6->sin6_addr)) {
+ mapped.sin_family = AF_INET;
+ mapped.sin_addr.s_addr =
+ in6->sin6_addr.s6_addr32[3];
+ mapped.sin_port = in6->sin6_port;
+ ss = (struct sockaddr_storage *)&mapped;
+ }
+ }
+
+ if (attrs[OVPN_A_PEER_LOCAL_IP]) {
+ local_ip = ovpn_nl_attr_local_ip(info, ovpn,
+ attrs,
+ ss->ss_family);
+ if (IS_ERR(local_ip)) {
+ ret = PTR_ERR(local_ip);
+ goto peer_release;
+ }
+ }
+
+ spin_lock_bh(&peer->lock);
+ /* 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);
+ spin_unlock_bh(&peer->lock);
+ goto peer_release;
+ }
+ spin_unlock_bh(&peer->lock);
+ }
+
+ /* VPN IPs cannot be updated, because they are hashed */
+ if (attrs[OVPN_A_PEER_VPN_IPV4])
+ peer->vpn_addrs.ipv4.s_addr =
+ nla_get_in_addr(attrs[OVPN_A_PEER_VPN_IPV4]);
+
+ /* VPN IPs cannot be updated, because they are hashed */
+ if (attrs[OVPN_A_PEER_VPN_IPV6])
+ 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(ovpn->dev,
+ "%s: %s peer with endpoint=%pIScp/%s id=%u VPN-IPv4=%pI4 VPN-IPv6=%pI6c\n",
+ __func__, (new_peer ? "adding" : "modifying"), ss,
+ peer->sock->sock->sk->sk_prot_creator->name, peer->id,
+ &peer->vpn_addrs.ipv4.s_addr, &peer->vpn_addrs.ipv6);
+
+ if (new_peer) {
+ 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\n",
+ peer->id, ret);
+ goto peer_release;
+ }
+ } else {
+ ovpn_peer_put(peer);
+ }
+
+ return 0;
+
+peer_release:
+ if (new_peer) {
+ /* release right away because peer is not really used in any
+ * context
+ */
+ ovpn_peer_release(peer);
+ kfree(peer);
+ } else {
+ ovpn_peer_put(peer);
+ }
+
+ return ret;
+}
+
+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 nlattr *attr;
+ void *hdr;
+
+ hdr = genlmsg_put(skb, portid, seq, &ovpn_nl_family, flags,
+ OVPN_CMD_SET_PEER);
+ if (!hdr)
+ return -ENOBUFS;
+
+ attr = nla_nest_start(skb, OVPN_A_PEER);
+ if (!attr)
+ goto err;
+
+ 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(skb, OVPN_A_PEER_SOCKADDR_REMOTE,
+ sizeof(bind->remote.in4),
+ &bind->remote.in4) ||
+ nla_put(skb, OVPN_A_PEER_LOCAL_IP,
+ sizeof(bind->local.ipv4),
+ &bind->local.ipv4))
+ goto err_unlock;
+ } else if (bind->remote.in4.sin_family == AF_INET6) {
+ if (nla_put(skb, OVPN_A_PEER_SOCKADDR_REMOTE,
+ sizeof(bind->remote.in6),
+ &bind->remote.in6) ||
+ nla_put(skb, OVPN_A_PEER_LOCAL_IP,
+ sizeof(bind->local.ipv6),
+ &bind->local.ipv6))
+ goto err_unlock;
+ }
+ }
+ rcu_read_unlock();
+
+ if (nla_put_net16(skb, OVPN_A_PEER_LOCAL_PORT,
+ inet_sk(peer->sock->sock->sk)->inet_sport) ||
+ /* 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 -EMSGSIZE;
}
int ovpn_nl_get_peer_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct nlattr *attrs[OVPN_A_PEER_MAX + 1];
+ struct ovpn_struct *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_get_peer_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
{
- return -EOPNOTSUPP;
+ const struct genl_info *info = genl_info_dump(cb);
+ struct ovpn_struct *ovpn;
+ struct ovpn_peer *peer;
+ struct net_device *dev;
+ int bkt, last_idx = cb->args[1], dumped = 0;
+
+ dev = ovpn_get_dev_from_attrs(sock_net(cb->skb->sk), info);
+ if (IS_ERR(dev))
+ return PTR_ERR(dev);
+
+ ovpn = netdev_priv(dev);
+
+ 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(dev, NULL);
+
+ /* 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_del_peer_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct nlattr *attrs[OVPN_A_PEER_MAX + 1];
+ struct ovpn_struct *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)
+ return -ENOENT;
+
+ netdev_dbg(ovpn->dev, "%s: peer id=%u\n", __func__, peer->id);
+ ret = ovpn_peer_del(peer, OVPN_DEL_PEER_REASON_USERSPACE);
+ ovpn_peer_put(peer);
+
+ return ret;
}
int ovpn_nl_set_key_doit(struct sk_buff *skb, struct genl_info *info)
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index 452fb9e521e4..c460a71dcc29 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -102,9 +102,9 @@ struct ovpn_peer *ovpn_peer_new(struct ovpn_struct *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)
__must_hold(&peer->lock)
{
struct ovpn_bind *bind;
@@ -215,7 +215,7 @@ void ovpn_peer_float(struct ovpn_peer *peer, struct sk_buff *skb)
* 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)
{
if (peer->sock)
ovpn_socket_put(peer->sock);
@@ -226,6 +226,8 @@ static void ovpn_peer_release(struct ovpn_peer *peer)
spin_unlock_bh(&peer->lock);
dst_cache_destroy(&peer->dst_cache);
+
+ netdev_put(peer->ovpn->dev, &peer->ovpn->dev_tracker);
}
/**
@@ -237,7 +239,6 @@ void ovpn_peer_release_kref(struct kref *kref)
struct ovpn_peer *peer = container_of(kref, struct ovpn_peer, refcount);
ovpn_peer_release(peer);
- netdev_put(peer->ovpn->dev, &peer->ovpn->dev_tracker);
kfree_rcu(peer, rcu);
}
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index 187e7d840705..b572664ea783 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h
@@ -131,6 +131,7 @@ 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);
/**
@@ -163,5 +164,8 @@ void ovpn_peer_update_local_endpoint(struct ovpn_peer *peer,
struct sk_buff *skb);
void ovpn_peer_float(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_ */
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 21/25] ovpn: implement key add/del/swap via netlink
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (19 preceding siblings ...)
2024-08-27 12:08 ` [PATCH net-next v6 20/25] ovpn: implement peer add/dump/delete via netlink Antonio Quartulli
@ 2024-08-27 12:08 ` Antonio Quartulli
2024-08-27 12:08 ` [PATCH net-next v6 22/25] ovpn: kill key and notify userspace in case of IV exhaustion Antonio Quartulli
` (3 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:08 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
This change introduces the netlink commands needed to add, delete and
swap keys for a specific peer.
Userspace is expected to use these commands to create, destroy and
rotate session keys for a specific peer.
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
drivers/net/ovpn/netlink-gen.c | 2 +-
drivers/net/ovpn/netlink.c | 224 ++++++++++++++++++++++++++++++++-
2 files changed, 222 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ovpn/netlink-gen.c b/drivers/net/ovpn/netlink-gen.c
index 594eb2c50eb5..f7c4c448b263 100644
--- a/drivers/net/ovpn/netlink-gen.c
+++ b/drivers/net/ovpn/netlink-gen.c
@@ -23,7 +23,7 @@ static const struct netlink_range_validation ovpn_a_peer_local_port_range = {
/* Common nested types */
const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_DIR + 1] = {
[OVPN_A_KEYCONF_SLOT] = NLA_POLICY_MAX(NLA_U32, 1),
- [OVPN_A_KEYCONF_KEY_ID] = NLA_POLICY_MAX(NLA_U32, 2),
+ [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),
diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c
index 9c9ad1e4cb9a..f106599821eb 100644
--- a/drivers/net/ovpn/netlink.c
+++ b/drivers/net/ovpn/netlink.c
@@ -678,19 +678,237 @@ int ovpn_nl_del_peer_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_set_key_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 renegotation 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_set_key_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct nlattr *p_attrs[OVPN_A_PEER_MAX + 1];
+ struct nlattr *attrs[OVPN_A_KEYCONF_MAX + 1];
+ struct ovpn_struct *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_PEER))
+ return -EINVAL;
+
+ ret = nla_parse_nested(p_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], p_attrs,
+ OVPN_A_PEER_ID) ||
+ NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_PEER], p_attrs,
+ OVPN_A_PEER_KEYCONF))
+ return -EINVAL;
+
+ ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX,
+ p_attrs[OVPN_A_PEER_KEYCONF],
+ ovpn_keyconf_nl_policy, info->extack);
+ if (ret)
+ return ret;
+
+ if (NL_REQ_ATTR_CHECK(info->extack, p_attrs[OVPN_A_PEER_KEYCONF], attrs,
+ OVPN_A_KEYCONF_SLOT) ||
+ NL_REQ_ATTR_CHECK(info->extack, p_attrs[OVPN_A_PEER_KEYCONF], attrs,
+ OVPN_A_KEYCONF_KEY_ID) ||
+ NL_REQ_ATTR_CHECK(info->extack, p_attrs[OVPN_A_PEER_KEYCONF], attrs,
+ OVPN_A_KEYCONF_CIPHER_ALG) ||
+ NL_REQ_ATTR_CHECK(info->extack, p_attrs[OVPN_A_PEER_KEYCONF], attrs,
+ OVPN_A_KEYCONF_ENCRYPT_DIR) ||
+ NL_REQ_ATTR_CHECK(info->extack, p_attrs[OVPN_A_PEER_KEYCONF], attrs,
+ OVPN_A_KEYCONF_DECRYPT_DIR))
+ return -EINVAL;
+
+ peer_id = nla_get_u32(p_attrs[OVPN_A_PEER_ID]);
+ 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 = 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, "%s: new key installed (id=%u) for peer %u\n",
+ __func__, pkr.key.key_id, peer_id);
+out:
+ ovpn_peer_put(peer);
+ return ret;
}
int ovpn_nl_swap_keys_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct ovpn_struct *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_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,
+ "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_del_key_doit(struct sk_buff *skb, struct genl_info *info)
{
- return -EOPNOTSUPP;
+ struct nlattr *p_attrs[OVPN_A_PEER_MAX + 1];
+ struct nlattr *attrs[OVPN_A_KEYCONF_MAX + 1];
+ struct ovpn_struct *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_PEER))
+ return -EINVAL;
+
+ ret = nla_parse_nested(p_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], p_attrs,
+ OVPN_A_PEER_ID) ||
+ NL_REQ_ATTR_CHECK(info->extack, info->attrs[OVPN_A_PEER], p_attrs,
+ OVPN_A_PEER_KEYCONF))
+ return -EINVAL;
+
+ ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX,
+ p_attrs[OVPN_A_PEER_KEYCONF],
+ ovpn_keyconf_nl_policy, info->extack);
+ if (ret)
+ return ret;
+
+ if (NL_REQ_ATTR_CHECK(info->extack, p_attrs[OVPN_A_PEER_KEYCONF], attrs,
+ OVPN_A_KEYCONF_SLOT))
+ return -EINVAL;
+
+ peer_id = nla_get_u32(p_attrs[OVPN_A_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;
}
/**
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 22/25] ovpn: kill key and notify userspace in case of IV exhaustion
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (20 preceding siblings ...)
2024-08-27 12:08 ` [PATCH net-next v6 21/25] ovpn: implement key add/del/swap " Antonio Quartulli
@ 2024-08-27 12:08 ` Antonio Quartulli
2024-08-27 12:08 ` [PATCH net-next v6 23/25] ovpn: notify userspace when a peer is deleted Antonio Quartulli
` (2 subsequent siblings)
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:08 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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 | 60 ++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/netlink.h | 2 ++
5 files changed, 96 insertions(+)
diff --git a/drivers/net/ovpn/crypto.c b/drivers/net/ovpn/crypto.c
index 0bceaef32f5b..3a576254b346 100644
--- a/drivers/net/ovpn/crypto.c
+++ b/drivers/net/ovpn/crypto.c
@@ -57,6 +57,25 @@ void ovpn_crypto_state_release(struct ovpn_crypto_state *cs)
mutex_destroy(&cs->mutex);
}
+/* 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;
+
+ mutex_lock(&cs->mutex);
+ if (rcu_access_pointer(cs->primary)->key_id == key_id) {
+ ks = rcu_replace_pointer(cs->primary, NULL,
+ lockdep_is_held(&cs->mutex));
+ } else if (rcu_access_pointer(cs->secondary)->key_id == key_id) {
+ ks = rcu_replace_pointer(cs->secondary, NULL,
+ lockdep_is_held(&cs->mutex));
+ }
+ mutex_unlock(&cs->mutex);
+
+ 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 228833db51a1..a620c3a3a43c 100644
--- a/drivers/net/ovpn/crypto.h
+++ b/drivers/net/ovpn/crypto.h
@@ -133,4 +133,6 @@ void ovpn_crypto_state_release(struct ovpn_crypto_state *cs);
void ovpn_crypto_key_slots_swap(struct ovpn_crypto_state *cs);
+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 28dab793de63..b6739fc2bf33 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -218,6 +218,19 @@ void ovpn_encrypt_post(struct sk_buff *skb, int ret)
if (unlikely(ret == -EINPROGRESS))
return;
+ 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 can be negotiated */
+ ovpn_nl_notify_swap_keys(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 f106599821eb..7cbad5a92b25 100644
--- a/drivers/net/ovpn/netlink.c
+++ b/drivers/net/ovpn/netlink.c
@@ -911,6 +911,66 @@ int ovpn_nl_del_key_doit(struct sk_buff *skb, struct genl_info *info)
return 0;
}
+/**
+ * ovpn_nl_notify_swap_keys - 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_notify_swap_keys(struct ovpn_peer *peer, u8 key_id)
+{
+ struct nlattr *p_attr, *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(100, GFP_ATOMIC);
+ if (!msg)
+ return -ENOMEM;
+
+ hdr = genlmsg_put(msg, 0, 0, &ovpn_nl_family, 0, OVPN_CMD_SWAP_KEYS);
+ if (!hdr) {
+ ret = -ENOBUFS;
+ goto err_free_msg;
+ }
+
+ if (nla_put_u32(msg, OVPN_A_IFINDEX, peer->ovpn->dev->ifindex))
+ goto err_cancel_msg;
+
+ p_attr = nla_nest_start(msg, OVPN_A_PEER);
+ if (!p_attr)
+ goto err_cancel_msg;
+
+ if (nla_put_u32(msg, OVPN_A_PEER_ID, peer->id))
+ goto err_cancel_msg;
+
+ k_attr = nla_nest_start(msg, OVPN_A_PEER_KEYCONF);
+ if (!k_attr)
+ 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);
+ nla_nest_end(msg, p_attr);
+ genlmsg_end(msg, hdr);
+
+ genlmsg_multicast_netns(&ovpn_nl_family, dev_net(peer->ovpn->dev), msg,
+ 0, OVPN_NLGRP_PEERS, GFP_ATOMIC);
+
+ return 0;
+
+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 9e87cf11d1e9..972d12fc8f93 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_notify_swap_keys(struct ovpn_peer *peer, u8 key_id);
+
#endif /* _NET_OVPN_NETLINK_H_ */
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 23/25] ovpn: notify userspace when a peer is deleted
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (21 preceding siblings ...)
2024-08-27 12:08 ` [PATCH net-next v6 22/25] ovpn: kill key and notify userspace in case of IV exhaustion Antonio Quartulli
@ 2024-08-27 12:08 ` Antonio Quartulli
2024-08-27 12:08 ` [PATCH net-next v6 24/25] ovpn: add basic ethtool support Antonio Quartulli
2024-08-27 12:08 ` [PATCH net-next v6 25/25] testing/selftest: add test tool and scripts for ovpn module Antonio Quartulli
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:08 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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 | 55 ++++++++++++++++++++++++++++++++++++++
drivers/net/ovpn/netlink.h | 1 +
drivers/net/ovpn/peer.c | 1 +
3 files changed, 57 insertions(+)
diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c
index 7cbad5a92b25..1933887ef281 100644
--- a/drivers/net/ovpn/netlink.c
+++ b/drivers/net/ovpn/netlink.c
@@ -911,6 +911,61 @@ int ovpn_nl_del_key_doit(struct sk_buff *skb, struct genl_info *info)
return 0;
}
+/**
+ * ovpn_nl_notify_del_peer - notify userspace about peer being deleted
+ * @peer: the peer being deleted
+ *
+ * Return: 0 on success or a negative error code otherwise
+ */
+int ovpn_nl_notify_del_peer(struct ovpn_peer *peer)
+{
+ 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(100, GFP_ATOMIC);
+ if (!msg)
+ return -ENOMEM;
+
+ hdr = genlmsg_put(msg, 0, 0, &ovpn_nl_family, 0, OVPN_CMD_DEL_PEER);
+ 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);
+
+ genlmsg_multicast_netns(&ovpn_nl_family, dev_net(peer->ovpn->dev), msg,
+ 0, OVPN_NLGRP_PEERS, GFP_ATOMIC);
+
+ return 0;
+
+err_cancel_msg:
+ genlmsg_cancel(msg, hdr);
+err_free_msg:
+ nlmsg_free(msg);
+ return ret;
+}
+
/**
* ovpn_nl_notify_swap_keys - 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 972d12fc8f93..5bb53bbd36d1 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_notify_del_peer(struct ovpn_peer *peer);
int ovpn_nl_notify_swap_keys(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 c460a71dcc29..3fc64af4f22a 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -238,6 +238,7 @@ void ovpn_peer_release_kref(struct kref *kref)
{
struct ovpn_peer *peer = container_of(kref, struct ovpn_peer, refcount);
+ ovpn_nl_notify_del_peer(peer);
ovpn_peer_release(peer);
kfree_rcu(peer, rcu);
}
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 24/25] ovpn: add basic ethtool support
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (22 preceding siblings ...)
2024-08-27 12:08 ` [PATCH net-next v6 23/25] ovpn: notify userspace when a peer is deleted Antonio Quartulli
@ 2024-08-27 12:08 ` Antonio Quartulli
2024-08-27 12:08 ` [PATCH net-next v6 25/25] testing/selftest: add test tool and scripts for ovpn module Antonio Quartulli
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:08 UTC (permalink / raw)
To: netdev; +Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli
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 0f9d79a05f4f..b29d16894e8d 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>
@@ -141,6 +142,19 @@ bool ovpn_dev_is_valid(const struct net_device *dev)
return dev->netdev_ops->ndo_start_xmit == ovpn_net_xmit;
}
+static void ovpn_get_drvinfo(struct net_device *dev,
+ struct ethtool_drvinfo *info)
+{
+ strscpy(info->driver, OVPN_FAMILY_NAME, 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,
+};
+
/* we register with rtnl to let core know that ovpn is a virtual driver and
* therefore ifaces should be destroyed when exiting a netns
*/
@@ -163,6 +177,7 @@ 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->rtnl_link_ops = &ovpn_link_ops;
--
2.44.2
^ permalink raw reply related [flat|nested] 58+ messages in thread* [PATCH net-next v6 25/25] testing/selftest: add test tool and scripts for ovpn module
2024-08-27 12:07 [PATCH net-next v6 00/25] Introducing OpenVPN Data Channel Offload Antonio Quartulli
` (23 preceding siblings ...)
2024-08-27 12:08 ` [PATCH net-next v6 24/25] ovpn: add basic ethtool support Antonio Quartulli
@ 2024-08-27 12:08 ` Antonio Quartulli
24 siblings, 0 replies; 58+ messages in thread
From: Antonio Quartulli @ 2024-08-27 12:08 UTC (permalink / raw)
To: netdev
Cc: kuba, pabeni, ryazanov.s.a, edumazet, andrew, sd,
Antonio Quartulli, shuah, linux-kselftest
The ovpn-cli tool can be compiled and used as selftest for the ovpn
kernel module.
It implementes the netlink API and can thus be integrated in any
script for more automated testing.
Along with the tool, 2 scripts are added that perform basic
functionality tests by means of network namespaces.
The scripts can be performed in sequence by running run.sh
Cc: shuah@kernel.org
Cc: linux-kselftest@vger.kernel.org
Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
---
tools/testing/selftests/Makefile | 1 +
tools/testing/selftests/net/ovpn/.gitignore | 2 +
tools/testing/selftests/net/ovpn/Makefile | 17 +
tools/testing/selftests/net/ovpn/config | 8 +
.../selftests/net/ovpn/data-test-tcp.sh | 9 +
tools/testing/selftests/net/ovpn/data-test.sh | 150 ++
tools/testing/selftests/net/ovpn/data64.key | 5 +
.../testing/selftests/net/ovpn/float-test.sh | 115 ++
tools/testing/selftests/net/ovpn/ovpn-cli.c | 1820 +++++++++++++++++
.../testing/selftests/net/ovpn/tcp_peers.txt | 1 +
.../testing/selftests/net/ovpn/udp_peers.txt | 5 +
11 files changed, 2133 insertions(+)
create mode 100644 tools/testing/selftests/net/ovpn/.gitignore
create mode 100644 tools/testing/selftests/net/ovpn/Makefile
create mode 100644 tools/testing/selftests/net/ovpn/config
create mode 100755 tools/testing/selftests/net/ovpn/data-test-tcp.sh
create mode 100755 tools/testing/selftests/net/ovpn/data-test.sh
create mode 100644 tools/testing/selftests/net/ovpn/data64.key
create mode 100755 tools/testing/selftests/net/ovpn/float-test.sh
create mode 100644 tools/testing/selftests/net/ovpn/ovpn-cli.c
create mode 100644 tools/testing/selftests/net/ovpn/tcp_peers.txt
create mode 100644 tools/testing/selftests/net/ovpn/udp_peers.txt
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index a5f1c0c27dff..c293f2717708 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -66,6 +66,7 @@ TARGETS += net/forwarding
TARGETS += net/hsr
TARGETS += net/mptcp
TARGETS += net/openvswitch
+TARGETS += net/ovpn
TARGETS += net/tcp_ao
TARGETS += net/netfilter
TARGETS += net/rds
diff --git a/tools/testing/selftests/net/ovpn/.gitignore b/tools/testing/selftests/net/ovpn/.gitignore
new file mode 100644
index 000000000000..ee44c081ca7c
--- /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 000000000000..171cf047497c
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/Makefile
@@ -0,0 +1,17 @@
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2020-2024 OpenVPN, Inc.
+#
+CFLAGS = -Wall -I../../../../../usr/include
+CFLAGS += $(shell pkg-config --cflags libnl-3.0 libnl-genl-3.0)
+
+LDFLAGS = -lmbedtls -lmbedcrypto
+LDFLAGS += $(shell pkg-config --libs libnl-3.0 libnl-genl-3.0)
+
+ovpn-cli: ovpn-cli.c
+
+TEST_PROGS = data-test.sh \
+ data-test-tcp.sh \
+ float-test.sh
+TEST_GEN_FILES = ovpn-cli
+
+include ../../lib.mk
diff --git a/tools/testing/selftests/net/ovpn/config b/tools/testing/selftests/net/ovpn/config
new file mode 100644
index 000000000000..5ff47de23c12
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/config
@@ -0,0 +1,8 @@
+CONFIG_NET=y
+CONFIG_INET=y
+CONFIG_NET_UDP_TUNNEL=y
+CONFIG_DST_CACHE=y
+CONFIG_CRYPTO_AES=y
+CONFIG_CRYPTO_GCM=y
+CONFIG_CRYPTO_CHACHA20POLY1305=y
+CONFIG_OVPN=y
diff --git a/tools/testing/selftests/net/ovpn/data-test-tcp.sh b/tools/testing/selftests/net/ovpn/data-test-tcp.sh
new file mode 100755
index 000000000000..65f05659b5fd
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/data-test-tcp.sh
@@ -0,0 +1,9 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2024 OpenVPN, Inc.
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+
+PROTO="TCP"
+
+source data-test.sh
diff --git a/tools/testing/selftests/net/ovpn/data-test.sh b/tools/testing/selftests/net/ovpn/data-test.sh
new file mode 100755
index 000000000000..8468defb1f1c
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/data-test.sh
@@ -0,0 +1,150 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2020-2024 OpenVPN, Inc.
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+
+#set -x
+set -e
+
+UDP_PEERS_FILE=${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}
+
+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_peer tun0 ${p} ${p} 10.10.${p}.2 1 5.5.5.$((${p} + 1))
+
+ 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() {
+ for p in $(seq 1 10); do
+ ip -n peer0 link del veth${p} 2>/dev/null || true
+ done
+ for p in $(seq 0 10); do
+ ip netns exec peer${p} ${OVPN_CLI} del_iface tun${p} 2>/dev/null || true
+ 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
+
+cleanup
+
+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
+
+for p in $(seq 1 ${NUM_PEERS}); do
+ ip netns exec peer0 ping -qfc 1000 -w 5 5.5.5.$((${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
+
+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
+
+ip netns exec peer0 ${OVPN_CLI} del_peer tun0 1
+
+echo "Setting timeout to 10s MP:"
+# bring ifaces down to prevent traffic being sent
+for p in $(seq 0 ${NUM_PEERS}); do
+ ip -n peer${p} link set tun${p} down
+done
+# set short timeout
+for p in $(seq 1 ${NUM_PEERS}); do
+ ip netns exec peer0 ${OVPN_CLI} set_peer tun0 ${p} 10 10 || true
+ ip netns exec peer${p} ${OVPN_CLI} set_peer tun${p} ${p} 0 0
+done
+# wait for peers to timeout
+sleep 15
+
+echo "Setting timeout to 10s P2P:"
+for p in $(seq 1 ${NUM_PEERS}); do
+ ip netns exec peer${p} ${OVPN_CLI} set_peer tun${p} ${p} 10 10
+done
+sleep 15
+
+cleanup
diff --git a/tools/testing/selftests/net/ovpn/data64.key b/tools/testing/selftests/net/ovpn/data64.key
new file mode 100644
index 000000000000..a99e88c4e290
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/data64.key
@@ -0,0 +1,5 @@
+jRqMACN7d7/aFQNT8S7jkrBD8uwrgHbG5OQZP2eu4R1Y7tfpS2bf5RHv06Vi163CGoaIiTX99R3B
+ia9ycAH8Wz1+9PWv51dnBLur9jbShlgZ2QHLtUc4a/gfT7zZwULXuuxdLnvR21DDeMBaTbkgbai9
+uvAa7ne1liIgGFzbv+Bas4HDVrygxIxuAnP5Qgc3648IJkZ0QEXPF+O9f0n5+QIvGCxkAUVx+5K6
+KIs+SoeWXnAopELmoGSjUpFtJbagXK82HfdqpuUxT2Tnuef0/14SzVE/vNleBNu2ZbyrSAaah8tE
+BofkPJUBFY+YQcfZNM5Dgrw3i+Bpmpq/gpdg5w==
diff --git a/tools/testing/selftests/net/ovpn/float-test.sh b/tools/testing/selftests/net/ovpn/float-test.sh
new file mode 100755
index 000000000000..5e113b767e78
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/float-test.sh
@@ -0,0 +1,115 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (C) 2020-2024 OpenVPN, Inc.
+#
+# Author: Antonio Quartulli <antonio@openvpn.net>
+
+#set -x
+set -e
+
+UDP_PEERS_FILE=${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}
+
+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_peer tun0 ${p} ${p} 10.10.${p}.2 1 5.5.5.$((${p} + 1))
+ 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 5.5.5.1 data64.key
+ fi
+ fi
+}
+
+cleanup() {
+ for p in $(seq 1 10); do
+ ip -n peer0 link del veth${p} 2>/dev/null || true
+ done
+ for p in $(seq 0 10); do
+ ip netns exec peer${p} ${OVPN_CLI} del_iface tun${p} 2>/dev/null || true
+ 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
+
+cleanup
+
+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
+
+for p in $(seq 1 ${NUM_PEERS}); do
+ ip netns exec peer0 ping -qfc 1000 -w 5 5.5.5.$((${p} + 1))
+done
+# 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 1000 -w 5 5.5.5.1
+done
+
+cleanup
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 000000000000..a10ad4881f13
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/ovpn-cli.c
@@ -0,0 +1,1820 @@
+// SPDX-License-Identifier: GPL-2.0
+/* OpenVPN data channel accelerator
+ *
+ * Copyright (C) 2020-2024 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 <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>
+
+/* we use strscpy to make checkpatch happy */
+#define strscpy strncpy
+
+/* 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)
+
+uint64_t 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
+
+struct nl_ctx {
+ struct nl_sock *nl_sock;
+ struct nl_msg *nl_msg;
+ struct nl_cb *nl_cb;
+
+ int ovpn_dco_id;
+};
+
+struct ovpn_ctx {
+ __u8 key_enc[KEY_LEN];
+ __u8 key_dec[KEY_LEN];
+ __u8 nonce[NONCE_LEN];
+
+ enum ovpn_cipher_alg cipher;
+
+ sa_family_t sa_family;
+
+ __u32 peer_id;
+ __u16 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_socket;
+
+ __u32 keepalive_interval;
+ __u32 keepalive_timeout;
+
+ enum ovpn_key_direction key_dir;
+ enum ovpn_key_slot key_slot;
+ int key_id;
+};
+
+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)__attribute__((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 *)((unsigned char *)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)__attribute__((unused)),
+ void *arg)
+{
+ int *status = arg;
+
+ *status = 0;
+ return NL_SKIP;
+}
+
+static int ovpn_nl_cb_ack(struct nl_msg (*msg)__attribute__((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_read_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;
+ }
+
+ 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_read_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_read_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;
+ 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;
+ }
+
+ memset((char *)&local_sock, 0, sizeof(local_sock));
+
+ 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;
+ size_t alen;
+ int ret = -1;
+
+ ctx = nl_ctx_alloc(ovpn, OVPN_CMD_SET_PEER);
+ 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:
+ alen = sizeof(struct sockaddr_in);
+ break;
+ case AF_INET6:
+ alen = sizeof(struct sockaddr_in6);
+ break;
+ default:
+ fprintf(stderr,
+ "Invalid family for remote socket address\n");
+ goto nla_put_failure;
+ }
+ NLA_PUT(ctx->nl_msg, OVPN_A_PEER_SOCKADDR_REMOTE, alen,
+ &ovpn->remote);
+ }
+
+ 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_SET_PEER);
+ 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_DEL_PEER);
+ 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)
+{
+ struct nlattr *attrs_peer[OVPN_A_PEER_MAX + 1];
+ struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
+ struct nlattr *attrs[OVPN_A_MAX + 1];
+ __u16 port = 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(attrs_peer, OVPN_A_PEER_MAX, nla_data(attrs[OVPN_A_PEER]),
+ nla_len(attrs[OVPN_A_PEER]), NULL);
+
+ if (attrs_peer[OVPN_A_PEER_ID])
+ fprintf(stderr, "* Peer %u\n",
+ nla_get_u32(attrs_peer[OVPN_A_PEER_ID]));
+
+ if (attrs_peer[OVPN_A_PEER_VPN_IPV4]) {
+ char buf[INET_ADDRSTRLEN];
+
+ inet_ntop(AF_INET, nla_data(attrs_peer[OVPN_A_PEER_VPN_IPV4]),
+ buf, sizeof(buf));
+ fprintf(stderr, "\tVPN IPv4: %s\n", buf);
+ }
+
+ if (attrs_peer[OVPN_A_PEER_VPN_IPV6]) {
+ char buf[INET6_ADDRSTRLEN];
+
+ inet_ntop(AF_INET6, nla_data(attrs_peer[OVPN_A_PEER_VPN_IPV6]),
+ buf, sizeof(buf));
+ fprintf(stderr, "\tVPN IPv6: %s\n", buf);
+ }
+
+ if (attrs_peer[OVPN_A_PEER_LOCAL_PORT])
+ port = ntohs(nla_get_u16(attrs_peer[OVPN_A_PEER_LOCAL_PORT]));
+
+ if (attrs_peer[OVPN_A_PEER_SOCKADDR_REMOTE]) {
+ struct sockaddr_storage ss;
+ struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)&ss;
+ struct sockaddr_in *in = (struct sockaddr_in *)&ss;
+
+ memcpy(&ss, nla_data(attrs_peer[OVPN_A_PEER_SOCKADDR_REMOTE]),
+ nla_len(attrs_peer[OVPN_A_PEER_SOCKADDR_REMOTE]));
+
+ if (in->sin_family == AF_INET) {
+ char buf[INET_ADDRSTRLEN];
+
+ if (attrs_peer[OVPN_A_PEER_LOCAL_IP]) {
+ void *p = attrs_peer[OVPN_A_PEER_LOCAL_IP];
+
+ inet_ntop(AF_INET, nla_data(p), buf,
+ sizeof(buf));
+ fprintf(stderr, "\tLocal: %s:%hu\n", buf,
+ port);
+ }
+
+ inet_ntop(AF_INET, &in->sin_addr, buf, sizeof(buf));
+ fprintf(stderr, "\tRemote: %s:%u\n", buf,
+ ntohs(in->sin_port));
+ } else if (in->sin_family == AF_INET6) {
+ char buf[INET6_ADDRSTRLEN];
+
+ if (attrs_peer[OVPN_A_PEER_LOCAL_IP]) {
+ void *p = attrs_peer[OVPN_A_PEER_LOCAL_IP];
+
+ inet_ntop(AF_INET6, nla_data(p), buf,
+ sizeof(buf));
+ fprintf(stderr, "\tLocal: %s\n", buf);
+ }
+
+ inet_ntop(AF_INET6, &in6->sin6_addr, buf, sizeof(buf));
+ fprintf(stderr, "\tRemote: %s:%u (scope-id: %u)\n", buf,
+ ntohs(in6->sin6_port),
+ ntohl(in6->sin6_scope_id));
+ }
+ }
+
+ if (attrs_peer[OVPN_A_PEER_KEEPALIVE_INTERVAL]) {
+ void *p = attrs_peer[OVPN_A_PEER_KEEPALIVE_INTERVAL];
+
+ fprintf(stderr, "\tKeepalive interval: %u sec\n",
+ nla_get_u32(p));
+ }
+
+ if (attrs_peer[OVPN_A_PEER_KEEPALIVE_TIMEOUT])
+ fprintf(stderr, "\tKeepalive timeout: %u sec\n",
+ nla_get_u32(attrs_peer[OVPN_A_PEER_KEEPALIVE_TIMEOUT]));
+
+ if (attrs_peer[OVPN_A_PEER_VPN_RX_BYTES])
+ fprintf(stderr, "\tVPN RX bytes: %" PRIu64 "\n",
+ nla_get_uint(attrs_peer[OVPN_A_PEER_VPN_RX_BYTES]));
+
+ if (attrs_peer[OVPN_A_PEER_VPN_TX_BYTES])
+ fprintf(stderr, "\tVPN TX bytes: %" PRIu64 "\n",
+ nla_get_uint(attrs_peer[OVPN_A_PEER_VPN_TX_BYTES]));
+
+ if (attrs_peer[OVPN_A_PEER_VPN_RX_PACKETS])
+ fprintf(stderr, "\tVPN RX packets: %" PRIu64 "\n",
+ nla_get_uint(attrs_peer[OVPN_A_PEER_VPN_RX_PACKETS]));
+
+ if (attrs_peer[OVPN_A_PEER_VPN_TX_PACKETS])
+ fprintf(stderr, "\tVPN TX packets: %" PRIu64 "\n",
+ nla_get_uint(attrs_peer[OVPN_A_PEER_VPN_TX_PACKETS]));
+
+ if (attrs_peer[OVPN_A_PEER_LINK_RX_BYTES])
+ fprintf(stderr, "\tLINK RX bytes: %" PRIu64 "\n",
+ nla_get_uint(attrs_peer[OVPN_A_PEER_LINK_RX_BYTES]));
+
+ if (attrs_peer[OVPN_A_PEER_LINK_TX_BYTES])
+ fprintf(stderr, "\tLINK TX bytes: %" PRIu64 "\n",
+ nla_get_uint(attrs_peer[OVPN_A_PEER_LINK_TX_BYTES]));
+
+ if (attrs_peer[OVPN_A_PEER_LINK_RX_PACKETS])
+ fprintf(stderr, "\tLINK RX packets: %" PRIu64 "\n",
+ nla_get_uint(attrs_peer[OVPN_A_PEER_LINK_RX_PACKETS]));
+
+ if (attrs_peer[OVPN_A_PEER_LINK_TX_PACKETS])
+ fprintf(stderr, "\tLINK TX packets: %" PRIu64 "\n",
+ nla_get_uint(attrs_peer[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_GET_PEER, 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 *peer, *keyconf, *key_dir;
+ struct nl_ctx *ctx;
+ int ret = -1;
+
+ ctx = nl_ctx_alloc(ovpn, OVPN_CMD_SET_KEY);
+ if (!ctx)
+ return -ENOMEM;
+
+ peer = nla_nest_start(ctx->nl_msg, OVPN_A_PEER);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id);
+
+ keyconf = nla_nest_start(ctx->nl_msg, OVPN_A_PEER_KEYCONF);
+ 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);
+
+ nla_nest_end(ctx->nl_msg, peer);
+
+ 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 *peer, *keyconf;
+ struct nl_ctx *ctx;
+ int ret = -1;
+
+ ctx = nl_ctx_alloc(ovpn, OVPN_CMD_DEL_KEY);
+ if (!ctx)
+ return -ENOMEM;
+
+ peer = nla_nest_start(ctx->nl_msg, OVPN_A_PEER);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_PEER_ID, ovpn->peer_id);
+
+ keyconf = nla_nest_start(ctx->nl_msg, OVPN_A_PEER_KEYCONF);
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_KEYCONF_SLOT, OVPN_KEY_SLOT_PRIMARY);
+ nla_nest_end(ctx->nl_msg, keyconf);
+
+ nla_nest_end(ctx->nl_msg, peer);
+
+ ret = ovpn_nl_msg_send(ctx, NULL);
+nla_put_failure:
+ nl_ctx_free(ctx);
+ return ret;
+}
+
+static int ovpn_swap_keys(struct ovpn_ctx *ovpn)
+{
+ struct nlattr *peer;
+ struct nl_ctx *ctx;
+ int ret = -1;
+
+ ctx = nl_ctx_alloc(ovpn, OVPN_CMD_SWAP_KEYS);
+ if (!ctx)
+ return -ENOMEM;
+
+ peer = 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, peer);
+
+ ret = ovpn_nl_msg_send(ctx, NULL);
+nla_put_failure:
+ nl_ctx_free(ctx);
+ return ret;
+}
+
+static int ovpn_handle_iface(struct nl_msg *msg, void *arg)
+{
+ 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_IFNAME]) {
+ fprintf(stderr, "no ifname in netlink message\n");
+ return NL_SKIP;
+ }
+
+ fprintf(stderr, "Created ifname: %s\n",
+ (char *)nla_data(attrs[OVPN_A_IFNAME]));
+
+ return NL_SKIP;
+}
+
+static int ovpn_new_iface(struct ovpn_ctx *ovpn)
+{
+ struct nl_ctx *ctx;
+ int ret = -1;
+
+ ctx = nl_ctx_alloc(ovpn, OVPN_CMD_NEW_IFACE);
+ if (!ctx)
+ return -ENOMEM;
+
+ NLA_PUT(ctx->nl_msg, OVPN_A_IFNAME, strlen(ovpn->ifname) + 1,
+ ovpn->ifname);
+
+ if (ovpn->mode_set)
+ NLA_PUT_U32(ctx->nl_msg, OVPN_A_MODE, ovpn->mode);
+
+ fprintf(stdout, "Creating interface %s with mode %u\n", ovpn->ifname,
+ ovpn->mode);
+
+ ret = ovpn_nl_msg_send(ctx, ovpn_handle_iface);
+nla_put_failure:
+ nl_ctx_free(ctx);
+ return ret;
+}
+
+static int ovpn_del_iface(struct ovpn_ctx *ovpn)
+{
+ struct nl_ctx *ctx;
+ int ret = -1;
+
+ ctx = nl_ctx_alloc(ovpn, OVPN_CMD_DEL_IFACE);
+ if (!ctx)
+ return -ENOMEM;
+
+ ret = ovpn_nl_msg_send(ctx, NULL);
+ nl_ctx_free(ctx);
+ return ret;
+}
+
+static int nl_seq_check(struct nl_msg *msg, void *arg)
+{
+ 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, struct nlmsgerr *err,
+ void *arg)
+{
+ int *ret = arg;
+
+ *ret = err->error;
+ return NL_STOP;
+}
+
+static int mcast_ack_handler(struct nl_msg *msg, 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];
+ __u32 ifindex;
+
+ fprintf(stderr, "received message from ovpn-dco\n");
+
+ 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_DEL_PEER:
+ /*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_DEL_PEER\n");
+ break;
+ default:
+ fprintf(stderr, "received unknown command: %d\n", gnlh->cmd);
+ return NL_STOP;
+ }
+
+ 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 void 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 = 0;
+ 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 != -EINTR)
+ ret = nl_recvmsgs(sock, cb);
+
+ nl_cb_put(cb);
+err_free:
+ nl_socket_free(sock);
+}
+
+static void usage(const char *cmd)
+{
+ fprintf(stderr, "Error: invalid arguments.\n\n");
+ fprintf(stderr,
+ "Usage %s <iface> <connect|listen|new_peer|new_multi_peer|set_peer|del_peer|new_key|del_key|recv|send|listen_mcast> [arguments..]\n",
+ cmd);
+ fprintf(stderr, "\tiface: tun interface name\n\n");
+
+ fprintf(stderr,
+ "* connect <peer_id> <raddr> <rport> <key file>: start connecting peer of TCP-based VPN session\n");
+ fprintf(stderr, "\tpeer-id: peer ID of the connecting peer\n");
+ fprintf(stderr, "\tremote-addr: peer IP address\n");
+ fprintf(stderr, "\tremote-port: peer TCP port\n");
+
+ fprintf(stderr,
+ "* listen <lport> <peers_file>: listen for incoming peer TCP connections\n");
+ fprintf(stderr, "\tlport: src TCP port\n");
+ fprintf(stderr,
+ "\tpeers_file: file containing one peer per line: Line format:\n");
+ fprintf(stderr, "\t\t<peer_id> <vpnaddr>\n\n");
+
+ fprintf(stderr,
+ "* new_peer <lport> <peer-id> <raddr> <rport> [vpnaddr]: add new peer\n");
+ fprintf(stderr,
+ "\tpeer-id: peer ID to be used in data packets to/from this peer\n");
+ fprintf(stderr, "\tlocal-port: local UDP port\n");
+ fprintf(stderr, "\tremote-addr: peer IP address\n");
+ fprintf(stderr, "\tremote-port: peer UDP port\n");
+ fprintf(stderr, "\tvpnaddr: peer VPN IP\n\n");
+
+ fprintf(stderr,
+ "* new_multi_peer <lport> <file>: add multiple peers as listed in the file\n");
+ fprintf(stderr, "\tlport: local UDP port to bind to\n");
+ fprintf(stderr,
+ "\tfile: text file containing one peer per line. Line format:\n");
+ fprintf(stderr, "\t\t<peer-id> <raddr> <rport> <vpnaddr>\n\n");
+
+ fprintf(stderr,
+ "* set_peer <peer-id> <keepalive_interval> <keepalive_timeout>: set peer attributes\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\n");
+
+ fprintf(stderr, "* del_peer <peer-id>: delete peer\n");
+ fprintf(stderr, "\tpeer-id: peer ID of the peer to delete\n\n");
+
+ fprintf(stderr,
+ "* new_key <peer-id> <slot> <key_id> <cipher> <key_dir> <key_file>: set data channel key\n");
+ fprintf(stderr,
+ "\tpeer-id: peer ID of the peer to configure the key for\n");
+ fprintf(stderr,
+ "\tcipher: cipher to use, supported: aes (AES-GCM), chachapoly (CHACHA20POLY1305), none\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\n");
+
+ fprintf(stderr,
+ "* del_key <peer-id>: erase existing data channel key\n");
+ fprintf(stderr, "\tpeer-id: peer ID of the peer to modify\n\n");
+
+ fprintf(stderr,
+ "* swap_keys <peer-id>: swap primary and seconday key slots\n");
+ fprintf(stderr, "\tpeer-id: peer ID of the peer to modify\n\n");
+
+ fprintf(stderr,
+ "* listen_mcast: listen to ovpn-dco 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) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+
+ return ovpn_parse_remote(ovpn, raddr, rport, vpnip);
+}
+
+static void 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), 0);
+
+ fprintf(stdout, "Sent %u bytes over TCP socket\n", ret);
+}
+
+static void ovpn_recv_tcp_data(int socket)
+{
+ uint8_t buf[1002];
+ uint16_t len;
+ int ret;
+
+ ret = recv(socket, buf, sizeof(buf), 0);
+
+ if (ret < 2) {
+ fprintf(stderr, ">>>> Error while reading TCP data: %d\n", ret);
+ return;
+ }
+
+ 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");
+ */
+}
+
+static int ovpn_parse_set_peer(struct ovpn_ctx *ovpn, int argc, char *argv[])
+{
+ if (argc < 5) {
+ usage(argv[0]);
+ return -1;
+ }
+
+ ovpn->keepalive_interval = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE) {
+ fprintf(stderr, "keepalive interval value out of range\n");
+ return -1;
+ }
+
+ ovpn->keepalive_timeout = strtoul(argv[4], NULL, 10);
+ if (errno == ERANGE) {
+ fprintf(stderr, "keepalive interval value out of range\n");
+ return -1;
+ }
+
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ struct ovpn_ctx ovpn;
+// struct nl_ctx *ctx;
+ int ret;
+
+ if (argc < 2) {
+ usage(argv[0]);
+ return -1;
+ }
+
+ memset(&ovpn, 0, sizeof(ovpn));
+ ovpn.sa_family = AF_INET;
+ ovpn.cli_socket = -1;
+
+ if (argc > 2) {
+ strscpy(ovpn.ifname, argv[2], IFNAMSIZ - 1);
+ ovpn.ifname[IFNAMSIZ - 1] = '\0';
+ }
+
+ /* all commands except new_iface expect a valid ifindex */
+ if (strcmp(argv[1], "new_iface")) {
+ /* in this case a ifname MUST be defined */
+ if (argc < 3) {
+ usage(argv[0]);
+ return -1;
+ }
+
+ ovpn.ifindex = if_nametoindex(ovpn.ifname);
+ if (!ovpn.ifindex) {
+ fprintf(stderr, "cannot find interface: %s\n",
+ strerror(errno));
+ return -1;
+ }
+ }
+
+ if (!strcmp(argv[1], "new_iface")) {
+ if (argc > 3) {
+ 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;
+ }
+
+ ret = ovpn_new_iface(&ovpn);
+ if (ret < 0) {
+ fprintf(stderr, "Cannot create interface %s: %d\n",
+ ovpn.ifname, ret);
+ return -1;
+ }
+ } else if (!strcmp(argv[1], "del_iface")) {
+ ret = ovpn_del_iface(&ovpn);
+ if (ret < 0) {
+ fprintf(stderr, "Cannot delete interface %s: %d\n",
+ ovpn.ifname, ret);
+ return -1;
+ }
+ } else if (!strcmp(argv[1], "listen")) {
+ char peer_id[10], vpnip[100];
+ int n;
+ FILE *fp;
+
+ if (argc < 4) {
+ usage(argv[0]);
+ return -1;
+ }
+
+ ovpn.lport = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE || ovpn.lport > 65535) {
+ fprintf(stderr, "lport value out of range\n");
+ return -1;
+ }
+
+ if (argc > 4 && !strcmp(argv[4], "ipv6"))
+ ovpn.sa_family = AF_INET6;
+
+ ret = ovpn_listen(&ovpn, ovpn.sa_family);
+ if (ret < 0) {
+ fprintf(stderr, "cannot listen on TCP socket\n");
+ return ret;
+ }
+
+ fp = fopen(argv[4], "r");
+ if (!fp) {
+ fprintf(stderr, "cannot open file: %s\n", argv[4]);
+ return -1;
+ }
+
+ while ((n = fscanf(fp, "%s %s\n", peer_id, vpnip)) == 2) {
+ struct ovpn_ctx peer_ctx = { 0 };
+
+ 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 the socket of the first peer to test TCP I/O */
+ if (ovpn.cli_socket < 0)
+ ovpn.cli_socket = 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;
+ }
+ }
+
+ if (ovpn.cli_socket >= 0)
+ ovpn_recv_tcp_data(ovpn.cli_socket);
+ } else if (!strcmp(argv[1], "connect")) {
+ if (argc < 5) {
+ usage(argv[0]);
+ return -1;
+ }
+
+ 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 ret;
+ }
+
+ 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 (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_read_key(argv[6], &ovpn);
+ if (ret)
+ return ret;
+
+ ret = ovpn_new_key(&ovpn);
+ if (ret < 0) {
+ fprintf(stderr, "cannot set key\n");
+ return ret;
+ }
+
+ ovpn_send_tcp_data(ovpn.socket);
+ }
+ } else if (!strcmp(argv[1], "new_peer")) {
+ if (argc < 7) {
+ usage(argv[0]);
+ return -1;
+ }
+
+ ovpn.lport = strtoul(argv[3], 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[4], argv[5], argv[6],
+ vpnip);
+ if (ret < 0)
+ return ret;
+
+ ret = ovpn_udp_socket(&ovpn, AF_INET6); //ovpn.sa_family ?
+ if (ret < 0)
+ return ret;
+
+ ret = ovpn_new_peer(&ovpn, false);
+ if (ret < 0) {
+ fprintf(stderr, "cannot add peer to VPN\n");
+ return ret;
+ }
+ } else if (!strcmp(argv[1], "new_multi_peer")) {
+ char peer_id[10], raddr[128], rport[10], vpnip[100];
+ FILE *fp;
+ int n;
+
+ if (argc < 5) {
+ usage(argv[0]);
+ return -1;
+ }
+
+ ovpn.lport = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE || ovpn.lport > 65535) {
+ fprintf(stderr, "lport value out of range\n");
+ return -1;
+ }
+
+ fp = fopen(argv[4], "r");
+ if (!fp) {
+ fprintf(stderr, "cannot open file: %s\n", argv[4]);
+ return -1;
+ }
+
+ ret = ovpn_udp_socket(&ovpn, AF_INET6);
+ if (ret < 0)
+ return ret;
+
+ 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;
+ }
+ }
+ } else if (!strcmp(argv[1], "set_peer")) {
+ ovpn.peer_id = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+
+ argv++;
+ argc--;
+
+ ret = ovpn_parse_set_peer(&ovpn, argc, argv);
+ if (ret < 0)
+ return ret;
+
+ ret = ovpn_set_peer(&ovpn);
+ if (ret < 0) {
+ fprintf(stderr, "cannot set peer to VPN\n");
+ return ret;
+ }
+ } else if (!strcmp(argv[1], "del_peer")) {
+ if (argc < 4) {
+ usage(argv[0]);
+ return -1;
+ }
+
+ ovpn.peer_id = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+
+ ret = ovpn_del_peer(&ovpn);
+ if (ret < 0) {
+ fprintf(stderr, "cannot delete peer to VPN\n");
+ return ret;
+ }
+ } else if (!strcmp(argv[1], "get_peer")) {
+ ovpn.peer_id = PEER_ID_UNDEF;
+ if (argc > 3)
+ ovpn.peer_id = strtoul(argv[3], NULL, 10);
+
+ fprintf(stderr, "List of peers connected to: %s\n",
+ ovpn.ifname);
+
+ ret = ovpn_get_peer(&ovpn);
+ if (ret < 0) {
+ fprintf(stderr, "cannot get peer(s): %d\n", ret);
+ return ret;
+ }
+ } else if (!strcmp(argv[1], "new_key")) {
+ if (argc < 8) {
+ usage(argv[0]);
+ return -1;
+ }
+
+ ovpn.peer_id = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+
+ int slot = strtoul(argv[4], NULL, 10);
+
+ if (errno == ERANGE || slot < 1 || slot > 2) {
+ fprintf(stderr, "ket 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;
+ }
+
+ ovpn.key_id = strtoul(argv[5], NULL, 10);
+ if (errno == ERANGE || ovpn.key_id > 2) {
+ fprintf(stderr, "ket ID out of range\n");
+ return -1;
+ }
+
+ ret = ovpn_read_cipher(argv[6], &ovpn);
+ if (ret < 0)
+ return ret;
+
+ ret = ovpn_read_key_direction(argv[7], &ovpn);
+ if (ret < 0)
+ return ret;
+
+ ret = ovpn_read_key(argv[8], &ovpn);
+ if (ret)
+ return ret;
+
+ ret = ovpn_new_key(&ovpn);
+ if (ret < 0) {
+ fprintf(stderr, "cannot set key\n");
+ return ret;
+ }
+ } else if (!strcmp(argv[1], "del_key")) {
+ if (argc < 3) {
+ usage(argv[0]);
+ return -1;
+ }
+
+ ovpn.peer_id = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+
+ argv++;
+ argc--;
+
+ ret = ovpn_del_key(&ovpn);
+ if (ret < 0) {
+ fprintf(stderr, "cannot delete key\n");
+ return ret;
+ }
+ } else if (!strcmp(argv[1], "swap_keys")) {
+ if (argc < 3) {
+ usage(argv[0]);
+ return -1;
+ }
+
+ ovpn.peer_id = strtoul(argv[3], NULL, 10);
+ if (errno == ERANGE) {
+ fprintf(stderr, "peer ID value out of range\n");
+ return -1;
+ }
+
+ argv++;
+ argc--;
+
+ ret = ovpn_swap_keys(&ovpn);
+ if (ret < 0) {
+ fprintf(stderr, "cannot swap keys\n");
+ return ret;
+ }
+ } else if (!strcmp(argv[1], "listen_mcast")) {
+ ovpn_listen_mcast();
+ } else {
+ usage(argv[0]);
+ return -1;
+ }
+
+ 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 000000000000..3b7f68bb7f64
--- /dev/null
+++ b/tools/testing/selftests/net/ovpn/tcp_peers.txt
@@ -0,0 +1 @@
+1 5.5.5.2
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 000000000000..32f14bd9347a
--- /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
--
2.44.2
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