v4.19.13 snapshot.
diff --git a/samples/bpf/test_ipip.sh b/samples/bpf/test_ipip.sh
new file mode 100755
index 0000000..9e507c3
--- /dev/null
+++ b/samples/bpf/test_ipip.sh
@@ -0,0 +1,179 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+function config_device {
+ ip netns add at_ns0
+ ip netns add at_ns1
+ ip netns add at_ns2
+ ip link add veth0 type veth peer name veth0b
+ ip link add veth1 type veth peer name veth1b
+ ip link add veth2 type veth peer name veth2b
+ ip link set veth0b up
+ ip link set veth1b up
+ ip link set veth2b up
+ ip link set dev veth0b mtu 1500
+ ip link set dev veth1b mtu 1500
+ ip link set dev veth2b mtu 1500
+ ip link set veth0 netns at_ns0
+ ip link set veth1 netns at_ns1
+ ip link set veth2 netns at_ns2
+ ip netns exec at_ns0 ip addr add 172.16.1.100/24 dev veth0
+ ip netns exec at_ns0 ip addr add 2401:db00::1/64 dev veth0 nodad
+ ip netns exec at_ns0 ip link set dev veth0 up
+ ip netns exec at_ns1 ip addr add 172.16.1.101/24 dev veth1
+ ip netns exec at_ns1 ip addr add 2401:db00::2/64 dev veth1 nodad
+ ip netns exec at_ns1 ip link set dev veth1 up
+ ip netns exec at_ns2 ip addr add 172.16.1.200/24 dev veth2
+ ip netns exec at_ns2 ip addr add 2401:db00::3/64 dev veth2 nodad
+ ip netns exec at_ns2 ip link set dev veth2 up
+ ip link add br0 type bridge
+ ip link set br0 up
+ ip link set dev br0 mtu 1500
+ ip link set veth0b master br0
+ ip link set veth1b master br0
+ ip link set veth2b master br0
+}
+
+function add_ipip_tunnel {
+ ip netns exec at_ns0 \
+ ip link add dev $DEV_NS type ipip local 172.16.1.100 remote 172.16.1.200
+ ip netns exec at_ns0 ip link set dev $DEV_NS up
+ ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+ ip netns exec at_ns1 \
+ ip link add dev $DEV_NS type ipip local 172.16.1.101 remote 172.16.1.200
+ ip netns exec at_ns1 ip link set dev $DEV_NS up
+ # same inner IP address in at_ns0 and at_ns1
+ ip netns exec at_ns1 ip addr add dev $DEV_NS 10.1.1.100/24
+
+ ip netns exec at_ns2 ip link add dev $DEV type ipip external
+ ip netns exec at_ns2 ip link set dev $DEV up
+ ip netns exec at_ns2 ip addr add dev $DEV 10.1.1.200/24
+}
+
+function add_ipip6_tunnel {
+ ip netns exec at_ns0 \
+ ip link add dev $DEV_NS type ip6tnl mode ipip6 local 2401:db00::1/64 remote 2401:db00::3/64
+ ip netns exec at_ns0 ip link set dev $DEV_NS up
+ ip netns exec at_ns0 ip addr add dev $DEV_NS 10.1.1.100/24
+ ip netns exec at_ns1 \
+ ip link add dev $DEV_NS type ip6tnl mode ipip6 local 2401:db00::2/64 remote 2401:db00::3/64
+ ip netns exec at_ns1 ip link set dev $DEV_NS up
+ # same inner IP address in at_ns0 and at_ns1
+ ip netns exec at_ns1 ip addr add dev $DEV_NS 10.1.1.100/24
+
+ ip netns exec at_ns2 ip link add dev $DEV type ip6tnl mode ipip6 external
+ ip netns exec at_ns2 ip link set dev $DEV up
+ ip netns exec at_ns2 ip addr add dev $DEV 10.1.1.200/24
+}
+
+function add_ip6ip6_tunnel {
+ ip netns exec at_ns0 \
+ ip link add dev $DEV_NS type ip6tnl mode ip6ip6 local 2401:db00::1/64 remote 2401:db00::3/64
+ ip netns exec at_ns0 ip link set dev $DEV_NS up
+ ip netns exec at_ns0 ip addr add dev $DEV_NS 2601:646::1/64
+ ip netns exec at_ns1 \
+ ip link add dev $DEV_NS type ip6tnl mode ip6ip6 local 2401:db00::2/64 remote 2401:db00::3/64
+ ip netns exec at_ns1 ip link set dev $DEV_NS up
+ # same inner IP address in at_ns0 and at_ns1
+ ip netns exec at_ns1 ip addr add dev $DEV_NS 2601:646::1/64
+
+ ip netns exec at_ns2 ip link add dev $DEV type ip6tnl mode ip6ip6 external
+ ip netns exec at_ns2 ip link set dev $DEV up
+ ip netns exec at_ns2 ip addr add dev $DEV 2601:646::2/64
+}
+
+function attach_bpf {
+ DEV=$1
+ SET_TUNNEL=$2
+ GET_TUNNEL=$3
+ ip netns exec at_ns2 tc qdisc add dev $DEV clsact
+ ip netns exec at_ns2 tc filter add dev $DEV egress bpf da obj tcbpf2_kern.o sec $SET_TUNNEL
+ ip netns exec at_ns2 tc filter add dev $DEV ingress bpf da obj tcbpf2_kern.o sec $GET_TUNNEL
+}
+
+function test_ipip {
+ DEV_NS=ipip_std
+ DEV=ipip_bpf
+ config_device
+# tcpdump -nei br0 &
+ cat /sys/kernel/debug/tracing/trace_pipe &
+
+ add_ipip_tunnel
+ attach_bpf $DEV ipip_set_tunnel ipip_get_tunnel
+
+ ip netns exec at_ns0 ping -c 1 10.1.1.200
+ ip netns exec at_ns2 ping -c 1 10.1.1.100
+ ip netns exec at_ns0 iperf -sD -p 5200 > /dev/null
+ ip netns exec at_ns1 iperf -sD -p 5201 > /dev/null
+ sleep 0.2
+ # tcp check _same_ IP over different tunnels
+ ip netns exec at_ns2 iperf -c 10.1.1.100 -n 5k -p 5200
+ ip netns exec at_ns2 iperf -c 10.1.1.100 -n 5k -p 5201
+ cleanup
+}
+
+# IPv4 over IPv6 tunnel
+function test_ipip6 {
+ DEV_NS=ipip_std
+ DEV=ipip_bpf
+ config_device
+# tcpdump -nei br0 &
+ cat /sys/kernel/debug/tracing/trace_pipe &
+
+ add_ipip6_tunnel
+ attach_bpf $DEV ipip6_set_tunnel ipip6_get_tunnel
+
+ ip netns exec at_ns0 ping -c 1 10.1.1.200
+ ip netns exec at_ns2 ping -c 1 10.1.1.100
+ ip netns exec at_ns0 iperf -sD -p 5200 > /dev/null
+ ip netns exec at_ns1 iperf -sD -p 5201 > /dev/null
+ sleep 0.2
+ # tcp check _same_ IP over different tunnels
+ ip netns exec at_ns2 iperf -c 10.1.1.100 -n 5k -p 5200
+ ip netns exec at_ns2 iperf -c 10.1.1.100 -n 5k -p 5201
+ cleanup
+}
+
+# IPv6 over IPv6 tunnel
+function test_ip6ip6 {
+ DEV_NS=ipip_std
+ DEV=ipip_bpf
+ config_device
+# tcpdump -nei br0 &
+ cat /sys/kernel/debug/tracing/trace_pipe &
+
+ add_ip6ip6_tunnel
+ attach_bpf $DEV ip6ip6_set_tunnel ip6ip6_get_tunnel
+
+ ip netns exec at_ns0 ping -6 -c 1 2601:646::2
+ ip netns exec at_ns2 ping -6 -c 1 2601:646::1
+ ip netns exec at_ns0 iperf -6sD -p 5200 > /dev/null
+ ip netns exec at_ns1 iperf -6sD -p 5201 > /dev/null
+ sleep 0.2
+ # tcp check _same_ IP over different tunnels
+ ip netns exec at_ns2 iperf -6c 2601:646::1 -n 5k -p 5200
+ ip netns exec at_ns2 iperf -6c 2601:646::1 -n 5k -p 5201
+ cleanup
+}
+
+function cleanup {
+ set +ex
+ pkill iperf
+ ip netns delete at_ns0
+ ip netns delete at_ns1
+ ip netns delete at_ns2
+ ip link del veth0
+ ip link del veth1
+ ip link del veth2
+ ip link del br0
+ pkill tcpdump
+ pkill cat
+ set -ex
+}
+
+cleanup
+echo "Testing IP tunnels..."
+test_ipip
+test_ipip6
+test_ip6ip6
+echo "*** PASS ***"