diff options
author | Shmulik Ladkani <shmulik.ladkani@gmail.com> | 2022-08-21 14:35:19 +0300 |
---|---|---|
committer | Daniel Borkmann <daniel@iogearbox.net> | 2022-08-23 23:48:12 +0300 |
commit | d6513727c2af39a8cffb0d9b07376e51a85f347f (patch) | |
tree | 8921b6c73ef0bd0cfcb561954bb42c0e8cc4f98e | |
parent | 5deedfbee84278da3b76fb7176dc3742f56eb370 (diff) | |
download | linux-d6513727c2af39a8cffb0d9b07376e51a85f347f.tar.xz |
bpf, selftests: Test BPF_FLOW_DISSECTOR_CONTINUE
The dissector program returns BPF_FLOW_DISSECTOR_CONTINUE (and avoids
setting skb->flow_keys or last_dissection map) in case it encounters
IP packets whose (outer) source address is 127.0.0.127.
Additional test is added to prog_tests/flow_dissector.c which sets
this address as test's pkk.iph.saddr, with the expected retval of
BPF_FLOW_DISSECTOR_CONTINUE.
Also, legacy test_flow_dissector.sh was similarly augmented.
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220821113519.116765-5-shmulik.ladkani@gmail.com
-rw-r--r-- | tools/testing/selftests/bpf/prog_tests/flow_dissector.c | 21 | ||||
-rw-r--r-- | tools/testing/selftests/bpf/progs/bpf_flow.c | 15 | ||||
-rwxr-xr-x | tools/testing/selftests/bpf/test_flow_dissector.sh | 8 |
3 files changed, 44 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/flow_dissector.c b/tools/testing/selftests/bpf/prog_tests/flow_dissector.c index 8fa3c454995e..7acca37a3d2b 100644 --- a/tools/testing/selftests/bpf/prog_tests/flow_dissector.c +++ b/tools/testing/selftests/bpf/prog_tests/flow_dissector.c @@ -8,6 +8,8 @@ #include "bpf_flow.skel.h" +#define FLOW_CONTINUE_SADDR 0x7f00007f /* 127.0.0.127 */ + #ifndef IP_MF #define IP_MF 0x2000 #endif @@ -400,6 +402,25 @@ struct test tests[] = { .flags = BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP, .retval = BPF_OK, }, + { + .name = "ipip-encap-dissector-continue", + .pkt.ipip = { + .eth.h_proto = __bpf_constant_htons(ETH_P_IP), + .iph.ihl = 5, + .iph.protocol = IPPROTO_IPIP, + .iph.tot_len = __bpf_constant_htons(MAGIC_BYTES), + .iph.saddr = __bpf_constant_htonl(FLOW_CONTINUE_SADDR), + .iph_inner.ihl = 5, + .iph_inner.protocol = IPPROTO_TCP, + .iph_inner.tot_len = + __bpf_constant_htons(MAGIC_BYTES) - + sizeof(struct iphdr), + .tcp.doff = 5, + .tcp.source = 99, + .tcp.dest = 9090, + }, + .retval = BPF_FLOW_DISSECTOR_CONTINUE, + }, }; static int create_tap(const char *ifname) diff --git a/tools/testing/selftests/bpf/progs/bpf_flow.c b/tools/testing/selftests/bpf/progs/bpf_flow.c index f266c757b3df..a20c5ed5e454 100644 --- a/tools/testing/selftests/bpf/progs/bpf_flow.c +++ b/tools/testing/selftests/bpf/progs/bpf_flow.c @@ -22,6 +22,8 @@ #define PROG(F) PROG_(F, _##F) #define PROG_(NUM, NAME) SEC("flow_dissector") int flow_dissector_##NUM +#define FLOW_CONTINUE_SADDR 0x7f00007f /* 127.0.0.127 */ + /* These are the identifiers of the BPF programs that will be used in tail * calls. Name is limited to 16 characters, with the terminating character and * bpf_func_ above, we have only 6 to work with, anything after will be cropped. @@ -143,6 +145,19 @@ int _dissect(struct __sk_buff *skb) { struct bpf_flow_keys *keys = skb->flow_keys; + if (keys->n_proto == bpf_htons(ETH_P_IP)) { + /* IP traffic from FLOW_CONTINUE_SADDR falls-back to + * standard dissector + */ + struct iphdr *iph, _iph; + + iph = bpf_flow_dissect_get_header(skb, sizeof(*iph), &_iph); + if (iph && iph->ihl == 5 && + iph->saddr == bpf_htonl(FLOW_CONTINUE_SADDR)) { + return BPF_FLOW_DISSECTOR_CONTINUE; + } + } + return parse_eth_proto(skb, keys->n_proto); } diff --git a/tools/testing/selftests/bpf/test_flow_dissector.sh b/tools/testing/selftests/bpf/test_flow_dissector.sh index dbd91221727d..5303ce0c977b 100755 --- a/tools/testing/selftests/bpf/test_flow_dissector.sh +++ b/tools/testing/selftests/bpf/test_flow_dissector.sh @@ -115,6 +115,14 @@ tc filter add dev lo parent ffff: protocol ip pref 1337 flower ip_proto \ # Send 10 IPv4/UDP packets from port 10. Filter should not drop any. ./test_flow_dissector -i 4 -f 10 +echo "Testing IPv4 from 127.0.0.127 (fallback to generic dissector)..." +# Send 10 IPv4/UDP packets from port 8. Filter should not drop any. +./test_flow_dissector -i 4 -S 127.0.0.127 -f 8 +# Send 10 IPv4/UDP packets from port 9. Filter should drop all. +./test_flow_dissector -i 4 -S 127.0.0.127 -f 9 -F +# Send 10 IPv4/UDP packets from port 10. Filter should not drop any. +./test_flow_dissector -i 4 -S 127.0.0.127 -f 10 + echo "Testing IPIP..." # Send 10 IPv4/IPv4/UDP packets from port 8. Filter should not drop any. ./with_addr.sh ./with_tunnels.sh ./test_flow_dissector -o 4 -e bare -i 4 \ |