tests: shell: add test to cover ct offload by using nft flowtables

To cover kernel patch ("netfilter: nf_tables: set transport offset from mac header for netdev/egress").

Signed-off-by: Yi Chen <yiche@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/tests/shell/testcases/packetpath/flowtables b/tests/shell/testcases/packetpath/flowtables
new file mode 100755 (executable)
index 0000000..852a05c
--- /dev/null
+++ b/tests/shell/testcases/packetpath/flowtables
@@ -0,0 +1,96 @@
+#! /bin/bash -x
+
+# NFT_TEST_SKIP(NFT_TEST_SKIP_slow)
+
+rnd=$(mktemp -u XXXXXXXX)
+R="flowtable-router-$rnd"
+C="flowtable-client-$rnd"
+S="flowtbale-server-$rnd"
+
+cleanup()
+{
+       for i in $R $C $S;do
+               kill $(ip netns pid $i) 2>/dev/null
+               ip netns del $i
+       done
+}
+
+trap cleanup EXIT
+
+ip netns add $R
+ip netns add $S
+ip netns add $C
+
+ip link add s_r netns $S type veth peer name r_s netns $R
+ip netns exec $S ip link set s_r up
+ip netns exec $R ip link set r_s up
+ip link add c_r netns $C type veth peer name r_c netns $R
+ip netns exec $R ip link set r_c up
+ip netns exec $C ip link set c_r up
+
+ip netns exec $S ip -6 addr add 2001:db8:ffff:22::1/64 dev s_r
+ip netns exec $C ip -6 addr add 2001:db8:ffff:21::2/64 dev c_r
+ip netns exec $R ip -6 addr add 2001:db8:ffff:22::fffe/64 dev r_s
+ip netns exec $R ip -6 addr add 2001:db8:ffff:21::fffe/64 dev r_c
+ip netns exec $R sysctl -w net.ipv6.conf.all.forwarding=1
+ip netns exec $C ip route add 2001:db8:ffff:22::/64 via 2001:db8:ffff:21::fffe dev c_r
+ip netns exec $S ip route add 2001:db8:ffff:21::/64 via 2001:db8:ffff:22::fffe dev s_r
+ip netns exec $S ethtool -K s_r tso off
+ip netns exec $C ethtool -K c_r tso off
+
+sleep 3
+ip netns exec $C ping -6 2001:db8:ffff:22::1 -c1 || exit 1
+
+ip netns exec $R nft -f - <<EOF
+table ip6 filter {
+        flowtable f1 {
+                hook ingress priority -100
+                devices = { r_c, r_s }
+        }
+
+        chain forward {
+                type filter hook forward priority filter; policy accept;
+                ip6 nexthdr tcp ct state established,related counter packets 0 bytes 0 flow add @f1 counter packets 0 bytes 0
+                ip6 nexthdr tcp ct state invalid counter packets 0 bytes 0 drop
+                tcp flags fin,rst counter packets 0 bytes 0 accept
+                meta l4proto tcp meta length < 100 counter packets 0 bytes 0 accept
+                ip6 nexthdr tcp counter packets 0 bytes 0 log drop
+        }
+}
+EOF
+
+if [ ! -r /proc/net/nf_conntrack ]
+then
+       echo "E: nf_conntrack unreadable, skipping" >&2 
+       exit 77
+fi
+
+ip netns exec $R nft list ruleset
+ip netns exec $R sysctl -w net.netfilter.nf_flowtable_tcp_timeout=5 || {
+       echo "E: set net.netfilter.nf_flowtable_tcp_timeout fail, skipping" >&2
+        exit 77
+}
+ip netns exec $R sysctl -w net.netfilter.nf_conntrack_tcp_timeout_established=86400 || {
+        echo "E: set net.netfilter.nf_conntrack_tcp_timeout_established fail, skipping" >&2
+        exit 77
+
+}
+
+# A trick to control the timing to send a packet
+ip netns exec $S socat TCP6-LISTEN:10001 GOPEN:pipefile,ignoreeof &
+sleep 1
+ip netns exec $C socat -b 2048 PIPE:pipefile TCP:[2001:db8:ffff:22::1]:10001 &
+sleep 1
+ip netns exec $R grep 'OFFLOAD' /proc/net/nf_conntrack   || { echo "check [OFFLOAD] tag (failed)"; exit 1; }
+ip netns exec $R cat /proc/net/nf_conntrack
+sleep 6
+ip netns exec $R grep 'OFFLOAD' /proc/net/nf_conntrack   && { echo "CT OFFLOAD timeout, fail back to classical path (failed)"; exit 1; }
+ip netns exec $R grep '8639[0-9]' /proc/net/nf_conntrack || { echo "check nf_conntrack_tcp_timeout_established (failed)"; exit 1; }
+ip netns exec $C echo "send sth" >> pipefile
+ip netns exec $R grep 'OFFLOAD' /proc/net/nf_conntrack   || { echo "traffic seen, back to OFFLOAD path (failed)"; exit 1; }
+ip netns exec $C sleep 3
+ip netns exec $C echo "send sth" >> pipefile
+ip netns exec $C sleep 3
+ip netns exec $R grep 'OFFLOAD' /proc/net/nf_conntrack   || { echo "Traffic seen in 5s (nf_flowtable_tcp_timeout), so stay in OFFLOAD (failed)"; exit 1; }
+
+exit 0