selftests: forwarding: Add router test with VID 1

Previous patches made it possible to setup VLAN devices with VID 1 over
mlxsw ports. Verify this functionality actually works by conducting a
simple router test over VID 1.

Adding this test as a generic test since it can be run using veth pairs
and it can also be useful for other physical devices where VID 1 was
considered reserved (knowingly or not).

Signed-off-by: Ido Schimmel <[e-mail]>
Reviewed-by: Petr Machata <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

tools/testing/selftests/net/forwarding/router_vid_1.sh

···
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+ALL_TESTS="ping_ipv4 ping_ipv6"
+NUM_NETIFS=4
+source lib.sh
+
+h1_create()
+{
+	vrf_create "vrf-h1"
+	ip link set dev vrf-h1 up
+
+	ip link set dev $h1 up
+	vlan_create $h1 1 vrf-h1 192.0.2.2/24 2001:db8:1::2/64
+
+	ip route add 198.51.100.0/24 vrf vrf-h1 nexthop via 192.0.2.1
+	ip route add 2001:db8:2::/64 vrf vrf-h1 nexthop via 2001:db8:1::1
+}
+
+h1_destroy()
+{
+	ip route del 2001:db8:2::/64 vrf vrf-h1
+	ip route del 198.51.100.0/24 vrf vrf-h1
+
+	vlan_destroy $h1 1
+	ip link set dev $h1 down
+
+	ip link set dev vrf-h1 down
+	vrf_destroy "vrf-h1"
+}
+
+h2_create()
+{
+	vrf_create "vrf-h2"
+	ip link set dev vrf-h2 up
+
+	ip link set dev $h2 up
+	vlan_create $h2 1 vrf-h2 198.51.100.2/24 2001:db8:2::2/64
+
+	ip route add 192.0.2.0/24 vrf vrf-h2 nexthop via 198.51.100.1
+	ip route add 2001:db8:1::/64 vrf vrf-h2 nexthop via 2001:db8:2::1
+}
+
+h2_destroy()
+{
+	ip route del 2001:db8:1::/64 vrf vrf-h2
+	ip route del 192.0.2.0/24 vrf vrf-h2
+
+	vlan_destroy $h2 1
+	ip link set dev $h2 down
+
+	ip link set dev vrf-h2 down
+	vrf_destroy "vrf-h2"
+}
+
+router_create()
+{
+	ip link set dev $rp1 up
+	ip link add link $rp1 name $rp1.1 up type vlan id 1
+
+	ip address add 192.0.2.1/24 dev $rp1.1
+	ip address add 2001:db8:1::1/64 dev $rp1.1
+
+	ip link set dev $rp2 up
+	ip link add link $rp2 name $rp2.1 up type vlan id 1
+
+	ip address add 198.51.100.1/24 dev $rp2.1
+	ip address add 2001:db8:2::1/64 dev $rp2.1
+}
+
+router_destroy()
+{
+	ip address del 2001:db8:2::1/64 dev $rp2.1
+	ip address del 198.51.100.1/24 dev $rp2.1
+
+	ip link del dev $rp2.1
+	ip link set dev $rp2 down
+
+	ip address del 2001:db8:1::1/64 dev $rp1.1
+	ip address del 192.0.2.1/24 dev $rp1.1
+
+	ip link del dev $rp1.1
+	ip link set dev $rp1 down
+}
+
+setup_prepare()
+{
+	h1=${NETIFS[p1]}
+	rp1=${NETIFS[p2]}
+
+	rp2=${NETIFS[p3]}
+	h2=${NETIFS[p4]}
+
+	vrf_prepare
+
+	h1_create
+	h2_create
+
+	router_create
+
+	forwarding_enable
+}
+
+cleanup()
+{
+	pre_cleanup
+
+	forwarding_restore
+
+	router_destroy
+
+	h2_destroy
+	h1_destroy
+
+	vrf_cleanup
+}
+
+ping_ipv4()
+{
+	ping_test $h1.1 198.51.100.2
+}
+
+ping_ipv6()
+{
+	ping6_test $h1.1 2001:db8:2::2
+}
+
+trap cleanup EXIT
+
+setup_prepare
+setup_wait
+
+tests_run
+
+exit $EXIT_STATUS