[PATCH net-next v2 0/4] selftests/net: add netkit container env and test

[PATCH net-next v2 0/4] selftests/net: add netkit container env and test

[David Wei]

Add a new Python selftest env NetDrvContEnv that sets up a pair of
netkit netdevs, with one inside of a netns, and a bpf prog that forwards
skbs from NETIF to the netkit inside the netns.

  NETIF           = "eth0"
  LOCAL_V6        = "2001:db8::1"
  REMOTE_V6       = "2001:db8::2"
  LOCAL_PREFIX_V6 = "fd00:cafe::"

          +-----------------------------+        +------------------------------+
  dst     | INIT NS                     |        | TEST NS                      |
  fd00:   | +-------------+             |        |                              |
  cafe::  | | NETIF       |             |  bpf   |                              |
  2:2 +---|>| 2001:db8::1 |             |redirect| +-------------------------+  |
      |   | |             |-------------|--------|>| Netkit                  |  |
      |   | +-------------+             | _peer  | | nk_guest                |  |
      |   | +-------------+ Netkit pair |        | | fe80::2/64              |  |
      |   | | Netkit      |.............|........|>| fd00:cafe::2:2/64       |  |
      |   | | nk_host     |             |        | +-------------------------+  |
      |   | | fe80::1/64  |             |        |                              |
      |   | +-------------+             |        | route:                       |
      |   |                             |        |   default                    |
      |   | route:                      |        |     via fe80::1 dev nk_guest |
      |   |   fd00:cafe::2:2/128        |        +------------------------------+
      |   |     via fe80::2 dev nk_host |
      |   +-----------------------------+
      |
      |   +---------------+
      |   | REMOTE        |
      +---| 2001:db8::2   |
          +---------------+

I will use this series for queue leasing selftests. Include a basic ping
test in this series as demonstration.

v2:
 - remove LOCAL_PREFIX_V4 in docs
 - mention in docs that LOCAL_PREFIX_V6 must not match LOCAL_V6
 - skip test if LOCAL_PREFIX_V6 matches LOCAL_V6
 - move NetDrvContEnv class vars above parent ctor
 - improve ASCII diagram to show remote, route, example addrs
 - use Python ipaddress instead of str manipulations
 - set forwarding/accept_ra

David Wei (4):
  selftests/net: Add bpf skb forwarding program
  selftests/net: Export Netlink class via lib.py
  selftests/net: Add env for container based tests
  selftests/net: Add netkit container ping test

 .../testing/selftests/drivers/net/README.rst  |  38 ++++
 .../testing/selftests/drivers/net/hw/Makefile |   1 +
 tools/testing/selftests/drivers/net/hw/config |   3 +
 .../drivers/net/hw/lib/py/__init__.py         |   7 +-
 .../selftests/drivers/net/hw/nk_forward.bpf.c |  49 +++++
 .../selftests/drivers/net/hw/nk_netns.py      |  23 ++
 .../selftests/drivers/net/lib/py/__init__.py  |  11 +-
 .../selftests/drivers/net/lib/py/env.py       | 208 ++++++++++++++++++
 .../testing/selftests/net/lib/py/__init__.py  |   4 +-
 tools/testing/selftests/net/lib/py/ynl.py     |   4 +-
 10 files changed, 336 insertions(+), 12 deletions(-)
 create mode 100644 tools/testing/selftests/drivers/net/hw/nk_forward.bpf.c
 create mode 100755 tools/testing/selftests/drivers/net/hw/nk_netns.py

-- 
2.47.3

[PATCH net-next v2 1/4] selftests/net: Add bpf skb forwarding program

[David Wei]

Add nk_forward.bpf.c, a BPF program that forwards skbs matching some IPv6
prefix received on eth0 ifindex to a specified netkit ifindex. This will
be needed by netkit container tests.

Signed-off-by: David Wei <dw@davidwei.uk>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
---
 .../selftests/drivers/net/hw/nk_forward.bpf.c | 49 +++++++++++++++++++
 1 file changed, 49 insertions(+)
 create mode 100644 tools/testing/selftests/drivers/net/hw/nk_forward.bpf.c

diff --git a/tools/testing/selftests/drivers/net/hw/nk_forward.bpf.c b/tools/testing/selftests/drivers/net/hw/nk_forward.bpf.c
new file mode 100644
index 000000000000..86ebfc1445b6
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/hw/nk_forward.bpf.c
@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <linux/pkt_cls.h>
+#include <linux/if_ether.h>
+#include <linux/ipv6.h>
+#include <linux/in6.h>
+#include <bpf/bpf_endian.h>
+#include <bpf/bpf_helpers.h>
+
+#define TC_ACT_OK 0
+#define ETH_P_IPV6 0x86DD
+
+#define ctx_ptr(field)		((void *)(long)(field))
+
+#define v6_p64_equal(a, b)	(a.s6_addr32[0] == b.s6_addr32[0] && \
+				 a.s6_addr32[1] == b.s6_addr32[1])
+
+volatile __u32 netkit_ifindex;
+volatile __u8 ipv6_prefix[16];
+
+SEC("tc/ingress")
+int tc_redirect_peer(struct __sk_buff *skb)
+{
+	void *data_end = ctx_ptr(skb->data_end);
+	void *data = ctx_ptr(skb->data);
+	struct in6_addr *peer_addr;
+	struct ipv6hdr *ip6h;
+	struct ethhdr *eth;
+
+	peer_addr = (struct in6_addr *)ipv6_prefix;
+
+	if (skb->protocol != bpf_htons(ETH_P_IPV6))
+		return TC_ACT_OK;
+
+	eth = data;
+	if ((void *)(eth + 1) > data_end)
+		return TC_ACT_OK;
+
+	ip6h = data + sizeof(struct ethhdr);
+	if ((void *)(ip6h + 1) > data_end)
+		return TC_ACT_OK;
+
+	if (!v6_p64_equal(ip6h->daddr, (*peer_addr)))
+		return TC_ACT_OK;
+
+	return bpf_redirect_peer(netkit_ifindex, 0);
+}
+
+char __license[] SEC("license") = "GPL";
-- 
2.47.3

[PATCH net-next v2 2/4] selftests/net: Export Netlink class via lib.py

[David Wei]

Making rtnl newlink calls requires constants defined in Netlink class in
pyynl. Export it.

Signed-off-by: David Wei <dw@davidwei.uk>
---
 tools/testing/selftests/drivers/net/lib/py/__init__.py | 4 ++--
 tools/testing/selftests/net/lib/py/__init__.py         | 4 ++--
 tools/testing/selftests/net/lib/py/ynl.py              | 4 ++--
 3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/tools/testing/selftests/drivers/net/lib/py/__init__.py b/tools/testing/selftests/drivers/net/lib/py/__init__.py
index 5872d114f142..e5ef5e949c12 100644
--- a/tools/testing/selftests/drivers/net/lib/py/__init__.py
+++ b/tools/testing/selftests/drivers/net/lib/py/__init__.py
@@ -19,7 +19,7 @@ try:
     # Import one by one to avoid pylint false positives
     from net.lib.py import NetNS, NetNSEnter, NetdevSimDev
     from net.lib.py import EthtoolFamily, NetdevFamily, NetshaperFamily, \
-        NlError, RtnlFamily, DevlinkFamily, PSPFamily
+        NlError, RtnlFamily, DevlinkFamily, PSPFamily, Netlink
     from net.lib.py import CmdExitFailure
     from net.lib.py import bkg, cmd, bpftool, bpftrace, defer, ethtool, \
         fd_read_timeout, ip, rand_port, rand_ports, wait_port_listen, wait_file
@@ -31,7 +31,7 @@ try:
 
     __all__ = ["NetNS", "NetNSEnter", "NetdevSimDev",
                "EthtoolFamily", "NetdevFamily", "NetshaperFamily",
-               "NlError", "RtnlFamily", "DevlinkFamily", "PSPFamily",
+               "NlError", "RtnlFamily", "DevlinkFamily", "PSPFamily", "Netlink",
                "CmdExitFailure",
                "bkg", "cmd", "bpftool", "bpftrace", "defer", "ethtool",
                "fd_read_timeout", "ip", "rand_port", "rand_ports",
diff --git a/tools/testing/selftests/net/lib/py/__init__.py b/tools/testing/selftests/net/lib/py/__init__.py
index a584e7f806a4..54e84282781c 100644
--- a/tools/testing/selftests/net/lib/py/__init__.py
+++ b/tools/testing/selftests/net/lib/py/__init__.py
@@ -16,7 +16,7 @@ from .utils import CmdExitFailure, fd_read_timeout, cmd, bkg, defer, \
     bpftool, ip, ethtool, bpftrace, rand_port, rand_ports, wait_port_listen, \
     wait_file, tool
 from .ynl import NlError, YnlFamily, EthtoolFamily, NetdevFamily, RtnlFamily, RtnlAddrFamily
-from .ynl import NetshaperFamily, DevlinkFamily, PSPFamily
+from .ynl import NetshaperFamily, DevlinkFamily, PSPFamily, Netlink
 
 __all__ = ["KSRC",
            "KsftFailEx", "KsftSkipEx", "KsftXfailEx", "ksft_pr", "ksft_eq",
@@ -31,4 +31,4 @@ __all__ = ["KSRC",
            "NetdevSim", "NetdevSimDev",
            "NetshaperFamily", "DevlinkFamily", "PSPFamily", "NlError",
            "YnlFamily", "EthtoolFamily", "NetdevFamily", "RtnlFamily",
-           "RtnlAddrFamily"]
+           "RtnlAddrFamily", "Netlink"]
diff --git a/tools/testing/selftests/net/lib/py/ynl.py b/tools/testing/selftests/net/lib/py/ynl.py
index 32c223e93b2c..a52b067f7589 100644
--- a/tools/testing/selftests/net/lib/py/ynl.py
+++ b/tools/testing/selftests/net/lib/py/ynl.py
@@ -13,14 +13,14 @@ try:
         SPEC_PATH = KSFT_DIR / "net/lib/specs"
 
         sys.path.append(tools_full_path.as_posix())
-        from net.lib.ynl.pyynl.lib import YnlFamily, NlError
+        from net.lib.ynl.pyynl.lib import YnlFamily, NlError, Netlink
     else:
         # Running in tree
         tools_full_path = KSRC / "tools"
         SPEC_PATH = KSRC / "Documentation/netlink/specs"
 
         sys.path.append(tools_full_path.as_posix())
-        from net.ynl.pyynl.lib import YnlFamily, NlError
+        from net.ynl.pyynl.lib import YnlFamily, NlError, Netlink
 except ModuleNotFoundError as e:
     ksft_pr("Failed importing `ynl` library from kernel sources")
     ksft_pr(str(e))
-- 
2.47.3

[PATCH net-next v2 3/4] selftests/net: Add env for container based tests

[David Wei]

Add an env NetDrvContEnv for container based selftests. This automates
the setup of a netns, netkit pair with one inside the netns, and a BPF
program that forwards skbs from the NETIF host inside the container.

Currently only netkit is used, but other virtual netdevs e.g. veth can
be used too.

Expect netkit container datapath selftests to have a publicly routable
IP prefix to assign to netkit in a container, such that packets will
land on eth0. The BPF skb forward program will then forward such packets
from the host netns to the container netns.

Signed-off-by: David Wei <dw@davidwei.uk>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
---
 .../testing/selftests/drivers/net/README.rst  |  38 ++++
 .../drivers/net/hw/lib/py/__init__.py         |   7 +-
 .../selftests/drivers/net/lib/py/__init__.py  |   7 +-
 .../selftests/drivers/net/lib/py/env.py       | 208 ++++++++++++++++++
 4 files changed, 254 insertions(+), 6 deletions(-)

diff --git a/tools/testing/selftests/drivers/net/README.rst b/tools/testing/selftests/drivers/net/README.rst
index eb838ae94844..24bf4e10024f 100644
--- a/tools/testing/selftests/drivers/net/README.rst
+++ b/tools/testing/selftests/drivers/net/README.rst
@@ -62,6 +62,44 @@ LOCAL_V4, LOCAL_V6, REMOTE_V4, REMOTE_V6
 
 Local and remote endpoint IP addresses.
 
+LOCAL_PREFIX_V6
+~~~~~~~~~~~~~~~
+
+Local IP prefix/subnet which can be used to allocate extra IP addresses (for
+network name spaces behind macvlan, veth, netkit devices). DUT must be
+reachable using these addresses from the endpoint.
+
+LOCAL_PREFIX_V6 must NOT match LOCAL_V6.
+
+Example:
+  NETIF           = "eth0"
+  LOCAL_V6        = "2001:db8::1"
+  REMOTE_V6       = "2001:db8::2"
+  LOCAL_PREFIX_V6 = "fd00:cafe::"
+
+          +-----------------------------+        +------------------------------+
+  dst     | INIT NS                     |        | TEST NS                      |
+  fd00:   | +-------------+             |        |                              |
+  cafe::  | | NETIF       |             |  bpf   |                              |
+  2:2 +---|>| 2001:db8::1 |             |redirect| +-------------------------+  |
+      |   | |             |-------------|--------|>| Netkit                  |  |
+      |   | +-------------+             | _peer  | | nk_guest                |  |
+      |   | +-------------+ Netkit pair |        | | fe80::2/64              |  |
+      |   | | Netkit      |.............|........|>| fd00:cafe::2:2/64       |  |
+      |   | | nk_host     |             |        | +-------------------------+  |
+      |   | | fe80::1/64  |             |        |                              |
+      |   | +-------------+             |        | route:                       |
+      |   |                             |        |   default                    |
+      |   | route:                      |        |     via fe80::1 dev nk_guest |
+      |   |   fd00:cafe::2:2/128        |        +------------------------------+
+      |   |     via fe80::2 dev nk_host |
+      |   +-----------------------------+
+      |
+      |   +---------------+
+      |   | REMOTE        |
+      +---| 2001:db8::2   |
+          +---------------+
+
 REMOTE_TYPE
 ~~~~~~~~~~~
 
diff --git a/tools/testing/selftests/drivers/net/hw/lib/py/__init__.py b/tools/testing/selftests/drivers/net/hw/lib/py/__init__.py
index 1971577d47e9..b8d9ae282390 100644
--- a/tools/testing/selftests/drivers/net/hw/lib/py/__init__.py
+++ b/tools/testing/selftests/drivers/net/hw/lib/py/__init__.py
@@ -3,6 +3,7 @@
 """
 Driver test environment (hardware-only tests).
 NetDrvEnv and NetDrvEpEnv are the main environment classes.
+NetDrvContEnv extends NetDrvEpEnv with netkit container support.
 Former is for local host only tests, latter creates / connects
 to a remote endpoint. See NIPA wiki for more information about
 running and writing driver tests.
@@ -30,7 +31,7 @@ try:
     from net.lib.py import ksft_eq, ksft_ge, ksft_in, ksft_is, ksft_lt, \
         ksft_ne, ksft_not_in, ksft_raises, ksft_true, ksft_gt, ksft_not_none
     from drivers.net.lib.py import GenerateTraffic, Remote, Iperf3Runner
-    from drivers.net.lib.py import NetDrvEnv, NetDrvEpEnv
+    from drivers.net.lib.py import NetDrvEnv, NetDrvEpEnv, NetDrvContEnv
 
     __all__ = ["NetNS", "NetNSEnter", "NetdevSimDev",
                "EthtoolFamily", "NetdevFamily", "NetshaperFamily",
@@ -45,8 +46,8 @@ try:
                "ksft_eq", "ksft_ge", "ksft_in", "ksft_is", "ksft_lt",
                "ksft_ne", "ksft_not_in", "ksft_raises", "ksft_true", "ksft_gt",
                "ksft_not_none", "ksft_not_none",
-               "NetDrvEnv", "NetDrvEpEnv", "GenerateTraffic", "Remote",
-               "Iperf3Runner"]
+               "NetDrvEnv", "NetDrvEpEnv", "NetDrvContEnv", "GenerateTraffic",
+               "Remote", "Iperf3Runner"]
 except ModuleNotFoundError as e:
     print("Failed importing `net` library from kernel sources")
     print(str(e))
diff --git a/tools/testing/selftests/drivers/net/lib/py/__init__.py b/tools/testing/selftests/drivers/net/lib/py/__init__.py
index e5ef5e949c12..374d4f08dd05 100644
--- a/tools/testing/selftests/drivers/net/lib/py/__init__.py
+++ b/tools/testing/selftests/drivers/net/lib/py/__init__.py
@@ -3,6 +3,7 @@
 """
 Driver test environment.
 NetDrvEnv and NetDrvEpEnv are the main environment classes.
+NetDrvContEnv extends NetDrvEpEnv with netkit container support.
 Former is for local host only tests, latter creates / connects
 to a remote endpoint. See NIPA wiki for more information about
 running and writing driver tests.
@@ -43,12 +44,12 @@ try:
                "ksft_ne", "ksft_not_in", "ksft_raises", "ksft_true", "ksft_gt",
                "ksft_not_none", "ksft_not_none"]
 
-    from .env import NetDrvEnv, NetDrvEpEnv
+    from .env import NetDrvEnv, NetDrvEpEnv, NetDrvContEnv
     from .load import GenerateTraffic, Iperf3Runner
     from .remote import Remote
 
-    __all__ += ["NetDrvEnv", "NetDrvEpEnv", "GenerateTraffic", "Remote",
-                "Iperf3Runner"]
+    __all__ += ["NetDrvEnv", "NetDrvEpEnv", "NetDrvContEnv", "GenerateTraffic",
+                "Remote", "Iperf3Runner"]
 except ModuleNotFoundError as e:
     print("Failed importing `net` library from kernel sources")
     print(str(e))
diff --git a/tools/testing/selftests/drivers/net/lib/py/env.py b/tools/testing/selftests/drivers/net/lib/py/env.py
index 41cc248ac848..36d98e1df15b 100644
--- a/tools/testing/selftests/drivers/net/lib/py/env.py
+++ b/tools/testing/selftests/drivers/net/lib/py/env.py
@@ -1,13 +1,16 @@
 # SPDX-License-Identifier: GPL-2.0
 
+import ipaddress
 import os
 import time
+import json
 from pathlib import Path
 from lib.py import KsftSkipEx, KsftXfailEx
 from lib.py import ksft_setup, wait_file
 from lib.py import cmd, ethtool, ip, CmdExitFailure
 from lib.py import NetNS, NetdevSimDev
 from .remote import Remote
+from . import bpftool, RtnlFamily, Netlink
 
 
 class NetDrvEnvBase:
@@ -289,3 +292,208 @@ class NetDrvEpEnv(NetDrvEnvBase):
                 data.get('stats-block-usecs', 0) / 1000 / 1000
 
         time.sleep(self._stats_settle_time)
+
+
+class NetDrvContEnv(NetDrvEpEnv):
+    """
+    Class for an environment with a netkit pair setup for forwarding traffic
+    between the physical interface and a network namespace.
+      NETIF           = "eth0"
+      LOCAL_V6        = "2001:db8::1"
+      REMOTE_V6       = "2001:db8::2"
+      LOCAL_PREFIX_V6 = "fd00:cafe::"
+
+              +-----------------------------+        +------------------------------+
+      dst     | INIT NS                     |        | TEST NS                      |
+      fd00:   | +-------------+             |        |                              |
+      cafe::  | | NETIF       |             |  bpf   |                              |
+      2:2 +---|>| 2001:db8::1 |             |redirect| +-------------------------+  |
+          |   | |             |-------------|--------|>| Netkit                  |  |
+          |   | +-------------+             | _peer  | | nk_guest                |  |
+          |   | +-------------+ Netkit pair |        | | fe80::2/64              |  |
+          |   | | Netkit      |.............|........|>| fd00:cafe::2:2/64       |  |
+          |   | | nk_host     |             |        | +-------------------------+  |
+          |   | | fe80::1/64  |             |        |                              |
+          |   | +-------------+             |        | route:                       |
+          |   |                             |        |   default                    |
+          |   | route:                      |        |     via fe80::1 dev nk_guest |
+          |   |   fd00:cafe::2:2/128        |        +------------------------------+
+          |   |     via fe80::2 dev nk_host |
+          |   +-----------------------------+
+          |
+          |   +---------------+
+          |   | REMOTE        |
+          +---| 2001:db8::2   |
+              +---------------+
+    """
+
+    def __init__(self, src_path, rxqueues=1, **kwargs):
+        self.netns = None
+        self._nk_host_ifname = None
+        self._nk_guest_ifname = None
+        self._tc_clsact_added = False
+        self._tc_attached = False
+        self._bpf_prog_pref = None
+        self._bpf_prog_id = None
+        self._init_ns_attached = False
+        self._old_fwd = None
+        self._old_accept_ra = None
+
+        super().__init__(src_path, **kwargs)
+
+        self.require_ipver("6")
+        local_prefix = self.env.get("LOCAL_PREFIX_V6")
+        if not local_prefix:
+            raise KsftSkipEx("LOCAL_PREFIX_V6 required")
+
+        try:
+            net = ipaddress.IPv6Network(local_prefix, strict=False)
+        except ValueError:
+            net = ipaddress.IPv6Network(f"{local_prefix}::/64", strict=False)
+        self.ipv6_prefix = str(net.network_address)
+        self.nk_host_ipv6 = f"{self.ipv6_prefix}2:1"
+        self.nk_guest_ipv6 = f"{self.ipv6_prefix}2:2"
+
+        local_v6 = ipaddress.IPv6Address(self.addr_v["6"])
+        if local_v6 in net:
+            raise KsftSkipEx("LOCAL_V6 must not fall within LOCAL_PREFIX_V6")
+
+        rtnl = RtnlFamily()
+        rtnl.newlink(
+            {
+                "linkinfo": {
+                    "kind": "netkit",
+                    "data": {
+                        "mode": "l2",
+                        "policy": "forward",
+                        "peer-policy": "forward",
+                    },
+                },
+                "num-rx-queues": rxqueues,
+            },
+            flags=[Netlink.NLM_F_CREATE, Netlink.NLM_F_EXCL],
+        )
+
+        all_links = ip("-d link show", json=True)
+        netkit_links = [link for link in all_links
+                        if link.get('linkinfo', {}).get('info_kind') == 'netkit'
+                        and 'UP' not in link.get('flags', [])]
+
+        if len(netkit_links) != 2:
+            raise KsftSkipEx("Failed to create netkit pair")
+
+        netkit_links.sort(key=lambda x: x['ifindex'])
+        self._nk_host_ifname = netkit_links[1]['ifname']
+        self._nk_guest_ifname = netkit_links[0]['ifname']
+        self.nk_host_ifindex = netkit_links[1]['ifindex']
+        self.nk_guest_ifindex = netkit_links[0]['ifindex']
+
+        self._setup_ns()
+        self._attach_bpf()
+
+    def __del__(self):
+        if self._tc_attached:
+            cmd(f"tc filter del dev {self.ifname} ingress pref {self._bpf_prog_pref}")
+            self._tc_attached = False
+
+        if self._tc_clsact_added:
+            cmd(f"tc qdisc del dev {self.ifname} clsact")
+            self._tc_clsact_added = False
+
+        if self._nk_host_ifname:
+            cmd(f"ip link del dev {self._nk_host_ifname}")
+            self._nk_host_ifname = None
+            self._nk_guest_ifname = None
+
+        if self._init_ns_attached:
+            cmd("ip netns del init", fail=False)
+            self._init_ns_attached = False
+
+        if self.netns:
+            del self.netns
+            self.netns = None
+
+        if self._old_fwd is not None:
+            with open("/proc/sys/net/ipv6/conf/all/forwarding", "w") as f:
+                f.write(self._old_fwd)
+            self._old_fwd = None
+        if self._old_accept_ra is not None:
+            with open("/proc/sys/net/ipv6/conf/all/accept_ra", "w") as f:
+                f.write(self._old_accept_ra)
+            self._old_accept_ra = None
+
+        super().__del__()
+
+    def _setup_ns(self):
+        fwd_path = "/proc/sys/net/ipv6/conf/all/forwarding"
+        ra_path = "/proc/sys/net/ipv6/conf/all/accept_ra"
+        with open(fwd_path) as f:
+            self._old_fwd = f.read().strip()
+        with open(ra_path) as f:
+            self._old_accept_ra = f.read().strip()
+        with open(fwd_path, "w") as f:
+            f.write("1")
+        with open(ra_path, "w") as f:
+            f.write("2")
+
+        self.netns = NetNS()
+        cmd("ip netns attach init 1")
+        self._init_ns_attached = True
+        ip("netns set init 0", ns=self.netns)
+        ip(f"link set dev {self._nk_guest_ifname} netns {self.netns.name}")
+        ip(f"link set dev {self._nk_host_ifname} up")
+        ip(f"-6 addr add fe80::1/64 dev {self._nk_host_ifname} nodad")
+        ip(f"-6 route add {self.nk_guest_ipv6}/128 via fe80::2 dev {self._nk_host_ifname}")
+
+        ip("link set lo up", ns=self.netns)
+        ip(f"link set dev {self._nk_guest_ifname} up", ns=self.netns)
+        ip(f"-6 addr add fe80::2/64 dev {self._nk_guest_ifname}", ns=self.netns)
+        ip(f"-6 addr add {self.nk_guest_ipv6}/64 dev {self._nk_guest_ifname} nodad", ns=self.netns)
+        ip(f"-6 route add default via fe80::1 dev {self._nk_guest_ifname}", ns=self.netns)
+
+    def _tc_ensure_clsact(self):
+        qdisc = json.loads(cmd(f"tc -j qdisc show dev {self.ifname}").stdout)
+        for q in qdisc:
+            if q['kind'] == 'clsact':
+                return
+        cmd(f"tc qdisc add dev {self.ifname} clsact")
+        self._tc_clsact_added = True
+
+    def _get_bpf_prog_ids(self):
+        filter = json.loads(cmd(f"tc -j filter show dev {self.ifname} ingress").stdout)
+        for bpf in filter:
+            if 'options' not in bpf:
+                continue
+            if bpf['options']['bpf_name'].startswith('nk_forward.bpf'):
+                return (bpf['pref'], bpf['options']['prog']['id'])
+        if self._bpf_prog_pref is None:
+            raise Exception("Failed to get BPF prog ID")
+
+    def _attach_bpf(self):
+        bpf_obj = self.test_dir / "nk_forward.bpf.o"
+        if not bpf_obj.exists():
+            raise KsftSkipEx("BPF prog not found")
+
+        self._tc_ensure_clsact()
+        cmd(f"tc filter add dev {self.ifname} ingress bpf obj {bpf_obj} sec tc/ingress direct-action")
+        self._tc_attached = True
+
+        (self._bpf_prog_pref, self._bpf_prog_id) = self._get_bpf_prog_ids()
+        prog_info = bpftool(f"prog show id {self._bpf_prog_id}", json=True)
+        map_ids = prog_info.get("map_ids", [])
+
+        bss_map_id = None
+        for map_id in map_ids:
+            map_info = bpftool(f"map show id {map_id}", json=True)
+            if map_info.get("name").endswith("bss"):
+                bss_map_id = map_id
+
+        if bss_map_id is None:
+            raise Exception("Failed to find .bss map")
+
+        ipv6_addr = ipaddress.IPv6Address(self.ipv6_prefix)
+        ipv6_bytes = ipv6_addr.packed
+        ifindex_bytes = self.nk_host_ifindex.to_bytes(4, byteorder='little')
+        value = ipv6_bytes + ifindex_bytes
+        value_hex = ' '.join(f'{b:02x}' for b in value)
+        bpftool(f"map update id {bss_map_id} key hex 00 00 00 00 value hex {value_hex}")
-- 
2.47.3

[PATCH net-next v2 4/4] selftests/net: Add netkit container ping test

[David Wei]

Add a basic ping test using NetDrvContEnv that sets up a netkit pair,
with one end in a netns. Use LOCAL_PREFIX_V6 and nk_forward BPF program
to ping from a remote host to the netkit in netns.

Signed-off-by: David Wei <dw@davidwei.uk>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
---
 .../testing/selftests/drivers/net/hw/Makefile |  1 +
 tools/testing/selftests/drivers/net/hw/config |  3 +++
 .../selftests/drivers/net/hw/nk_netns.py      | 23 +++++++++++++++++++
 3 files changed, 27 insertions(+)
 create mode 100755 tools/testing/selftests/drivers/net/hw/nk_netns.py

diff --git a/tools/testing/selftests/drivers/net/hw/Makefile b/tools/testing/selftests/drivers/net/hw/Makefile
index a64140333a46..91df028abfc0 100644
--- a/tools/testing/selftests/drivers/net/hw/Makefile
+++ b/tools/testing/selftests/drivers/net/hw/Makefile
@@ -32,6 +32,7 @@ TEST_PROGS = \
 	irq.py \
 	loopback.sh \
 	nic_timestamp.py \
+	nk_netns.py \
 	pp_alloc_fail.py \
 	rss_api.py \
 	rss_ctx.py \
diff --git a/tools/testing/selftests/drivers/net/hw/config b/tools/testing/selftests/drivers/net/hw/config
index 2307aa001be1..b6524040418e 100644
--- a/tools/testing/selftests/drivers/net/hw/config
+++ b/tools/testing/selftests/drivers/net/hw/config
@@ -1,3 +1,4 @@
+CONFIG_BPF_SYSCALL=y
 CONFIG_FAIL_FUNCTION=y
 CONFIG_FAULT_INJECTION=y
 CONFIG_FAULT_INJECTION_DEBUG_FS=y
@@ -5,6 +6,8 @@ CONFIG_FUNCTION_ERROR_INJECTION=y
 CONFIG_IO_URING=y
 CONFIG_IPV6=y
 CONFIG_IPV6_GRE=y
+CONFIG_NETKIT=y
+CONFIG_NET_CLS_BPF=y
 CONFIG_NET_IPGRE=y
 CONFIG_NET_IPGRE_DEMUX=y
 CONFIG_UDMABUF=y
diff --git a/tools/testing/selftests/drivers/net/hw/nk_netns.py b/tools/testing/selftests/drivers/net/hw/nk_netns.py
new file mode 100755
index 000000000000..afa8638195d8
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/hw/nk_netns.py
@@ -0,0 +1,23 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+from lib.py import ksft_run, ksft_exit
+from lib.py import NetDrvContEnv
+from lib.py import cmd
+
+
+def test_ping(cfg) -> None:
+    cfg.require_ipver("6")
+
+    cmd(f"ping -c 1 -W5 {cfg.nk_guest_ipv6}", host=cfg.remote)
+    cmd(f"ping -c 1 -W5 {cfg.remote_addr_v['6']}", ns=cfg.netns)
+
+
+def main() -> None:
+    with NetDrvContEnv(__file__) as cfg:
+        ksft_run([test_ping], args=(cfg,))
+    ksft_exit()
+
+
+if __name__ == "__main__":
+    main()
-- 
2.47.3

Re: [PATCH net-next v2 2/4] selftests/net: Export Netlink class via lib.py

[Jakub Kicinski]

On Sun,  1 Mar 2026 21:33:13 -0800 David Wei wrote:
> diff --git a/tools/testing/selftests/net/lib/py/ynl.py b/tools/testing/selftests/net/lib/py/ynl.py
> index 32c223e93b2c..a52b067f7589 100644
> --- a/tools/testing/selftests/net/lib/py/ynl.py
> +++ b/tools/testing/selftests/net/lib/py/ynl.py
> @@ -13,14 +13,14 @@ try:
>          SPEC_PATH = KSFT_DIR / "net/lib/specs"
>  
>          sys.path.append(tools_full_path.as_posix())
> -        from net.lib.ynl.pyynl.lib import YnlFamily, NlError
> +        from net.lib.ynl.pyynl.lib import YnlFamily, NlError, Netlink

index a52b067f7589..b42986bf39e3 100644
--- a/tools/testing/selftests/net/lib/py/ynl.py
+++ b/tools/testing/selftests/net/lib/py/ynl.py
@@ -27,6 +27,12 @@ from .ksft import ksft_pr, ktap_result
     ktap_result(True, comment="SKIP")
     sys.exit(4)
 
+__all__ = [
+    "NlError", "Netlink", "YnlFamily", "SPEC_PATH",
+    "EthtoolFamily", "RtnlFamily", "RtnlAddrFamily",
+    "NetdevFamily", "NetshaperFamily", "DevlinkFamily", "PSPFamily",
+]
+
 #
 # Wrapper classes, loading the right specs
 # Set schema='' to avoid jsonschema validation, it's slow

Re: [PATCH net-next v2 3/4] selftests/net: Add env for container based tests

[Jakub Kicinski]

On Sun,  1 Mar 2026 21:33:14 -0800 David Wei wrote:
> +class NetDrvContEnv(NetDrvEpEnv):
> +    """
> +    Class for an environment with a netkit pair setup for forwarding traffic
> +    between the physical interface and a network namespace.
> +      NETIF           = "eth0"
> +      LOCAL_V6        = "2001:db8::1"
> +      REMOTE_V6       = "2001:db8::2"
> +      LOCAL_PREFIX_V6 = "fd00:cafe::"

Since you have to respin for the Makefile issue - could you rewrite this
to use 2001:db8 for all addresses? ULA is a funny and odd thing.

LOCAL_V6        = "2001:db8:1::1"
REMOTE_V6       = "2001:db8:1::2"
LOCAL_PREFIX_V6 = "2001:db8:2::0/64"

?
> +        try:
> +            net = ipaddress.IPv6Network(local_prefix, strict=False)
> +        except ValueError:
> +            net = ipaddress.IPv6Network(f"{local_prefix}::/64", strict=False)

dunno if the fallback is really necessary, not including the prefix
length is a bit of a bug IMO.

Re: [PATCH net-next v2 4/4] selftests/net: Add netkit container ping test

[Jakub Kicinski]

On Sun,  1 Mar 2026 21:33:15 -0800 David Wei wrote:
> diff --git a/tools/testing/selftests/drivers/net/hw/config b/tools/testing/selftests/drivers/net/hw/config
> index 2307aa001be1..b6524040418e 100644
> --- a/tools/testing/selftests/drivers/net/hw/config
> +++ b/tools/testing/selftests/drivers/net/hw/config
> @@ -1,3 +1,4 @@
> +CONFIG_BPF_SYSCALL=y
>  CONFIG_FAIL_FUNCTION=y
>  CONFIG_FAULT_INJECTION=y
>  CONFIG_FAULT_INJECTION_DEBUG_FS=y
> @@ -5,6 +6,8 @@ CONFIG_FUNCTION_ERROR_INJECTION=y
>  CONFIG_IO_URING=y
>  CONFIG_IPV6=y
>  CONFIG_IPV6_GRE=y
> +CONFIG_NETKIT=y
> +CONFIG_NET_CLS_BPF=y
>  CONFIG_NET_IPGRE=y
>  CONFIG_NET_IPGRE_DEMUX=y
>  CONFIG_UDMABUF=y

the sort order we use ignores _ characters:

$ ../nipa/tests/patch/check_selftest/validate_config_format.py tools/testing/selftests/drivers/net/hw/config
Validation errors in tools/testing/selftests/drivers/net/hw/config:
Lines 9-10 invalid order, CONFIG_NET_CLS_BPF=y should be before CONFIG_NETKIT=y


Also here and in patch 2 we're getting new pylint --disable=R warnings.
Please fix them where possible.