selftests: forwarding: Test neighbor updates when mirroring to gretap

Test that when a mirror to gretap or ip6gretap netdevice is configured,
changes to neighbors are reflected.
Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/net/forwarding/mirror_gre_neigh.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# This test uses standard topology for testing gretap. See
+# mirror_gre_topo_lib.sh for more details.
+#
+# Test for mirroring to gretap and ip6gretap, such that the neighbor entry for
+# the tunnel remote address has invalid address at the time that the mirroring
+# is set up. Later on, the neighbor is deleted and it is expected to be
+# reinitialized using the usual ARP process, and the mirroring offload updated.
+
+NUM_NETIFS=6
+source lib.sh
+source mirror_lib.sh
+source mirror_gre_lib.sh
+source mirror_gre_topo_lib.sh
+
+setup_prepare()
+{
+	h1=${NETIFS[p1]}
+	swp1=${NETIFS[p2]}
+
+	swp2=${NETIFS[p3]}
+	h2=${NETIFS[p4]}
+
+	swp3=${NETIFS[p5]}
+	h3=${NETIFS[p6]}
+
+	vrf_prepare
+	mirror_gre_topo_create
+
+	ip address add dev $swp3 192.0.2.129/28
+	ip address add dev $h3 192.0.2.130/28
+
+	ip address add dev $swp3 2001:db8:2::1/64
+	ip address add dev $h3 2001:db8:2::2/64
+}
+
+cleanup()
+{
+	pre_cleanup
+
+	ip address del dev $h3 2001:db8:2::2/64
+	ip address del dev $swp3 2001:db8:2::1/64
+
+	ip address del dev $h3 192.0.2.130/28
+	ip address del dev $swp3 192.0.2.129/28
+
+	mirror_gre_topo_destroy
+	vrf_cleanup
+}
+
+test_span_gre_neigh()
+{
+	local addr=$1; shift
+	local tundev=$1; shift
+	local direction=$1; shift
+	local what=$1; shift
+
+	RET=0
+
+	ip neigh replace dev $swp3 $addr lladdr 00:11:22:33:44:55
+	mirror_install $swp1 $direction $tundev "matchall $tcflags"
+	fail_test_span_gre_dir $tundev ingress
+	ip neigh del dev $swp3 $addr
+	quick_test_span_gre_dir $tundev ingress
+	mirror_uninstall $swp1 $direction
+
+	log_test "$direction $what: neighbor change ($tcflags)"
+}
+
+test_all()
+{
+	slow_path_trap_install $swp1 ingress
+	slow_path_trap_install $swp1 egress
+
+	test_span_gre_neigh 192.0.2.130 gt4 ingress "mirror to gretap"
+	test_span_gre_neigh 192.0.2.130 gt4 egress "mirror to gretap"
+	test_span_gre_neigh 2001:db8:2::2 gt6 ingress "mirror to ip6gretap"
+	test_span_gre_neigh 2001:db8:2::2 gt6 egress "mirror to ip6gretap"
+
+	slow_path_trap_uninstall $swp1 egress
+	slow_path_trap_uninstall $swp1 ingress
+}
+
+trap cleanup EXIT
+
+setup_prepare
+setup_wait
+
+tcflags="skip_hw"
+test_all
+
+if ! tc_offload_check; then
+	echo "WARN: Could not test offloaded functionality"
+else
+	tcflags="skip_sw"
+	test_all
+fi
+
+exit $EXIT_STATUS