selftests: netfilter: nft_flowtable.sh: Add IPIP flowtable selftest

Introduce specific selftest for IPIP flowtable SW acceleration in
nft_flowtable.sh

Signed-off-by: Lorenzo Bianconi <[e-mail]>
Signed-off-by: Pablo Neira Ayuso <[e-mail]>

tools/testing/selftests/net/netfilter/nft_flowtable.sh

···
 	ip netns exec "$nsr1" nft list ruleset
 fi
 
+# IPIP tunnel test:
+# Add IPIP tunnel interfaces and check flowtable acceleration.
+test_ipip() {
+if ! ip -net "$nsr1" link add name tun0 type ipip \
+     local 192.168.10.1 remote 192.168.10.2 >/dev/null;then
+	echo "SKIP: could not add ipip tunnel"
+	[ "$ret" -eq 0 ] && ret=$ksft_skip
+	return
+fi
+ip -net "$nsr1" link set tun0 up
+ip -net "$nsr1" addr add 192.168.100.1/24 dev tun0
+ip netns exec "$nsr1" sysctl net.ipv4.conf.tun0.forwarding=1 > /dev/null
+
+ip -net "$nsr2" link add name tun0 type ipip local 192.168.10.2 remote 192.168.10.1
+ip -net "$nsr2" link set tun0 up
+ip -net "$nsr2" addr add 192.168.100.2/24 dev tun0
+ip netns exec "$nsr2" sysctl net.ipv4.conf.tun0.forwarding=1 > /dev/null
+
+ip -net "$nsr1" route change default via 192.168.100.2
+ip -net "$nsr2" route change default via 192.168.100.1
+ip -net "$ns2" route add default via 10.0.2.1
+
+ip netns exec "$nsr1" nft -a insert rule inet filter forward 'meta oif tun0 accept'
+ip netns exec "$nsr1" nft -a insert rule inet filter forward \
+	'meta oif "veth0" tcp sport 12345 ct mark set 1 flow add @f1 counter name routed_repl accept'
+
+if ! test_tcp_forwarding_nat "$ns1" "$ns2" 1 "IPIP tunnel"; then
+	echo "FAIL: flow offload for ns1/ns2 with IPIP tunnel" 1>&2
+	ip netns exec "$nsr1" nft list ruleset
+	ret=1
+fi
+
+# Create vlan tagged devices for IPIP traffic.
+ip -net "$nsr1" link add link veth1 name veth1.10 type vlan id 10
+ip -net "$nsr1" link set veth1.10 up
+ip -net "$nsr1" addr add 192.168.20.1/24 dev veth1.10
+ip netns exec "$nsr1" sysctl net.ipv4.conf.veth1/10.forwarding=1 > /dev/null
+ip netns exec "$nsr1" nft -a insert rule inet filter forward 'meta oif veth1.10 accept'
+ip -net "$nsr1" link add name tun1 type ipip local 192.168.20.1 remote 192.168.20.2
+ip -net "$nsr1" link set tun1 up
+ip -net "$nsr1" addr add 192.168.200.1/24 dev tun1
+ip -net "$nsr1" route change default via 192.168.200.2
+ip netns exec "$nsr1" sysctl net.ipv4.conf.tun1.forwarding=1 > /dev/null
+ip netns exec "$nsr1" nft -a insert rule inet filter forward 'meta oif tun1 accept'
+
+ip -net "$nsr2" link add link veth0 name veth0.10 type vlan id 10
+ip -net "$nsr2" link set veth0.10 up
+ip -net "$nsr2" addr add 192.168.20.2/24 dev veth0.10
+ip netns exec "$nsr2" sysctl net.ipv4.conf.veth0/10.forwarding=1 > /dev/null
+ip -net "$nsr2" link add name tun1 type ipip local 192.168.20.2 remote 192.168.20.1
+ip -net "$nsr2" link set tun1 up
+ip -net "$nsr2" addr add 192.168.200.2/24 dev tun1
+ip -net "$nsr2" route change default via 192.168.200.1
+ip netns exec "$nsr2" sysctl net.ipv4.conf.tun1.forwarding=1 > /dev/null
+
+if ! test_tcp_forwarding_nat "$ns1" "$ns2" 1 "IPIP tunnel over vlan"; then
+	echo "FAIL: flow offload for ns1/ns2 with IPIP tunnel over vlan" 1>&2
+	ip netns exec "$nsr1" nft list ruleset
+	ret=1
+fi
+
+# Restore the previous configuration
+ip -net "$nsr1" route change default via 192.168.10.2
+ip -net "$nsr2" route change default via 192.168.10.1
+ip -net "$ns2" route del default via 10.0.2.1
+}
+
 # Another test:
 # Add bridge interface br0 to Router1, with NAT enabled.
 test_bridge() {
···
 ip -net "$nsr1" addr add dead:1::1/64 dev veth0 nodad
 ip -net "$nsr1" link set up dev veth0
 }
+
+test_ipip
 
 test_bridge