Add ipip6 and ip6ip decap support for bpf_skb_adjust_room(). Main use case is for using cls_bpf on ingress hook to decapsulate IPv4 over IPv6 and IPv6 over IPv4 tunnel packets. And add ipip6 and ip6ip decap testcases to verify that bpf_skb_adjust_room() correctly decapsulate ipip6 and ip6ip tunnel packets. $./test_tc_tunnel.sh ipip encap 192.168.1.1 to 192.168.1.2, type ipip, mac none len 100 test basic connectivity 0 test bpf encap without decap (expect failure) Ncat: TIMEOUT. 1 test bpf encap with tunnel device decap 0 test bpf encap with bpf decap 0 OK ipip6 encap 192.168.1.1 to 192.168.1.2, type ipip6, mac none len 100 test basic connectivity 0 test bpf encap without decap (expect failure) Ncat: TIMEOUT. 1 test bpf encap with tunnel device decap 0 test bpf encap with bpf decap 0 OK ip6ip6 encap fd::1 to fd::2, type ip6tnl, mac none len 100 test basic connectivity 0 test bpf encap without decap (expect failure) Ncat: TIMEOUT. 1 test bpf encap with tunnel device decap 0 test bpf encap with bpf decap 0 OK sit encap fd::1 to fd::2, type sit, mac none len 100 test basic connectivity 0 test bpf encap without decap (expect failure) Ncat: TIMEOUT. 1 test bpf encap with tunnel device decap 0 test bpf encap with bpf decap 0 OK ... OK. All tests passed v3: - Fix compilation failure of selftests/bpf. - Combine two new branches in bpf_skb_adjust_room(). - Simplify description for new flags BPF_F_ADJ_ROOM_DECAP_L3_IP*. v2: - Use decap flags to indicate the new IP header. Do not rely on skb->encapsulation. Ziyang Xuan (2): bpf: Add ipip6 and ip6ip decap support for bpf_skb_adjust_room() selftests/bpf: add ipip6 and ip6ip decap to test_tc_tunnel include/uapi/linux/bpf.h | 7 ++ net/core/filter.c | 31 ++++++- tools/include/uapi/linux/bpf.h | 7 ++ .../selftests/bpf/progs/test_tc_tunnel.c | 91 ++++++++++++++++++- tools/testing/selftests/bpf/test_tc_tunnel.sh | 15 +-- 5 files changed, 142 insertions(+), 9 deletions(-) -- 2.25.1