selftests/net: Add netkit container tests

Add two tests using NetDrvContEnv. One basic test 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.

Second is a selftest for netkit queue leasing, using io_uring zero copy
test binary inside of a netns with netkit. This checks that memory
providers can be bound against virtual queues in a netkit within a
netns that are leasing from a physical netdev in the default netns.

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>
Link: https://patch.msgid.link/20260115082603.219152-17-daniel@iogearbox.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

tools/testing/selftests/drivers/net/hw/Makefile

@@ -32,6 +32,8 @@ TEST_PROGS = \
 	irq.py \
 	loopback.sh \
 	nic_timestamp.py \
+	nk_netns.py \
+	nk_qlease.py \
 	pp_alloc_fail.py \
 	rss_api.py \
 	rss_ctx.py \

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()

tools/testing/selftests/drivers/net/hw/nk_qlease.py

@@ -0,0 +1,55 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+import re
+from os import path
+from lib.py import ksft_run, ksft_exit
+from lib.py import NetDrvContEnv
+from lib.py import bkg, cmd, defer, ethtool, rand_port, wait_port_listen
+
+
+def create_rss_ctx(cfg):
+    output = ethtool(f"-X {cfg.ifname} context new start {cfg.src_queue} equal 1").stdout
+    values = re.search(r'New RSS context is (\d+)', output).group(1)
+    return int(values)
+
+
+def set_flow_rule(cfg):
+    output = ethtool(f"-N {cfg.ifname} flow-type tcp6 dst-port {cfg.port} action {cfg.src_queue}").stdout
+    values = re.search(r'ID (\d+)', output).group(1)
+    return int(values)
+
+
+def set_flow_rule_rss(cfg, rss_ctx_id):
+    output = ethtool(f"-N {cfg.ifname} flow-type tcp6 dst-port {cfg.port} context {rss_ctx_id}").stdout
+    values = re.search(r'ID (\d+)', output).group(1)
+    return int(values)
+
+
+def test_iou_zcrx(cfg) -> None:
+    cfg.require_ipver('6')
+
+    ethtool(f"-X {cfg.ifname} equal {cfg.src_queue}")
+    defer(ethtool, f"-X {cfg.ifname} default")
+
+    flow_rule_id = set_flow_rule(cfg)
+    defer(ethtool, f"-N {cfg.ifname} delete {flow_rule_id}")
+
+    rx_cmd = f"ip netns exec {cfg.netns.name} {cfg.bin_local} -s -p {cfg.port} -i {cfg._nk_guest_ifname} -q {cfg.nk_queue}"
+    tx_cmd = f"{cfg.bin_remote} -c -h {cfg.nk_guest_ipv6} -p {cfg.port} -l 12840"
+    with bkg(rx_cmd, exit_wait=True):
+        wait_port_listen(cfg.port, proto="tcp", ns=cfg.netns)
+        cmd(tx_cmd, host=cfg.remote)
+
+
+def main() -> None:
+    with NetDrvContEnv(__file__, lease=True) as cfg:
+        cfg.bin_local = path.abspath(path.dirname(__file__) + "/../../../drivers/net/hw/iou-zcrx")
+        cfg.bin_remote = cfg.remote.deploy(cfg.bin_local)
+        cfg.port = rand_port()
+        ksft_run([test_iou_zcrx], args=(cfg,))
+    ksft_exit()
+
+
+if __name__ == "__main__":
+    main()