[PATCH bpf-next v3 13/13] selftests/bpf: convert bpf tunnel test to encap modes

[Willem de Bruijn]

From: Willem de Bruijn <will...@google.com>

Make the tests correctly annotate skbs with tunnel metadata.

This makes the gso tests succeed. Enable them.

Signed-off-by: Willem de Bruijn <will...@google.com>
---
 .../selftests/bpf/progs/test_tc_tunnel.c      | 19 +++++++++++++++----
 tools/testing/selftests/bpf/test_tc_tunnel.sh | 10 ++++------
 2 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/tools/testing/selftests/bpf/progs/test_tc_tunnel.c 
b/tools/testing/selftests/bpf/progs/test_tc_tunnel.c
index 3b79dffb8103..f541c2de947d 100644
--- a/tools/testing/selftests/bpf/progs/test_tc_tunnel.c
+++ b/tools/testing/selftests/bpf/progs/test_tc_tunnel.c
@@ -70,8 +70,13 @@ static __always_inline int encap_ipv4(struct __sk_buff *skb, 
bool with_gre)
        if (tcph.dest != __bpf_constant_htons(cfg_port))
                return TC_ACT_OK;
 
-       flags = BPF_F_ADJ_ROOM_FIXED_GSO;
-       olen = with_gre ? sizeof(h_outer) : sizeof(h_outer.ip);
+       flags = BPF_F_ADJ_ROOM_FIXED_GSO | BPF_F_ADJ_ROOM_ENCAP_L3_IPV4;
+       if (with_gre) {
+               flags |= BPF_F_ADJ_ROOM_ENCAP_L4_GRE;
+               olen = sizeof(h_outer);
+       } else {
+               olen = sizeof(h_outer.ip);
+       }
 
        /* add room between mac and network header */
        if (bpf_skb_adjust_room(skb, olen, BPF_ADJ_ROOM_MAC, flags))
@@ -119,8 +124,14 @@ static __always_inline int encap_ipv6(struct __sk_buff 
*skb, bool with_gre)
        if (tcph.dest != __bpf_constant_htons(cfg_port))
                return TC_ACT_OK;
 
-       flags = BPF_F_ADJ_ROOM_FIXED_GSO;
-       olen = with_gre ? sizeof(h_outer) : sizeof(h_outer.ip);
+       flags = BPF_F_ADJ_ROOM_FIXED_GSO | BPF_F_ADJ_ROOM_ENCAP_L3_IPV6;
+       if (with_gre) {
+               flags |= BPF_F_ADJ_ROOM_ENCAP_L4_GRE;
+               olen = sizeof(h_outer);
+       } else {
+               olen = sizeof(h_outer.ip);
+       }
+
 
        /* add room between mac and network header */
        if (bpf_skb_adjust_room(skb, olen, BPF_ADJ_ROOM_MAC, flags))
diff --git a/tools/testing/selftests/bpf/test_tc_tunnel.sh 
b/tools/testing/selftests/bpf/test_tc_tunnel.sh
index cda5317790d2..dcf320626931 100755
--- a/tools/testing/selftests/bpf/test_tc_tunnel.sh
+++ b/tools/testing/selftests/bpf/test_tc_tunnel.sh
@@ -97,13 +97,11 @@ if [[ "$#" -eq "0" ]]; then
        echo "ip6 gre"
        $0 ipv6 ip6gre 100
 
-       # disabled until passes SKB_GSO_DODGY checks
-       # echo "ip gre gso"
-       # $0 ipv4 gre 2000
+       echo "ip gre gso"
+       $0 ipv4 gre 2000
 
-       # disabled until passes SKB_GSO_DODGY checks
-       # echo "ip6 gre gso"
-       # $0 ipv6 ip6gre 2000
+       echo "ip6 gre gso"
+       $0 ipv6 ip6gre 2000
 
        echo "OK. All tests passed"
        exit 0
-- 
2.21.0.392.gf8f6787159e-goog