[PATCH bpf-next v3 2/3] selftests/bpf: Add connmark read test

From: Daniel Xu
Date: Wed Aug 10 2022 - 19:17:13 EST


Test that the prog can read from the connection mark. This test is nice
because it ensures progs can interact with netfilter subsystem
correctly.

Signed-off-by: Daniel Xu <dxu@xxxxxxxxx>
---
tools/testing/selftests/bpf/prog_tests/bpf_nf.c | 3 ++-
tools/testing/selftests/bpf/progs/test_bpf_nf.c | 3 +++
2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_nf.c b/tools/testing/selftests/bpf/prog_tests/bpf_nf.c
index 317978cac029..7232f6dcd252 100644
--- a/tools/testing/selftests/bpf/prog_tests/bpf_nf.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_nf.c
@@ -44,7 +44,7 @@ static int connect_to_server(int srv_fd)

static void test_bpf_nf_ct(int mode)
{
- const char *iptables = "iptables -t raw %s PREROUTING -j CT";
+ const char *iptables = "iptables -t raw %s PREROUTING -j CONNMARK --set-mark 42/0";
int srv_fd = -1, client_fd = -1, srv_client_fd = -1;
struct sockaddr_in peer_addr = {};
struct test_bpf_nf *skel;
@@ -114,6 +114,7 @@ static void test_bpf_nf_ct(int mode)
/* expected status is IPS_SEEN_REPLY */
ASSERT_EQ(skel->bss->test_status, 2, "Test for ct status update ");
ASSERT_EQ(skel->data->test_exist_lookup, 0, "Test existing connection lookup");
+ ASSERT_EQ(skel->bss->test_exist_lookup_mark, 43, "Test existing connection lookup ctmark");
end:
if (srv_client_fd != -1)
close(srv_client_fd);
diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
index 84e0fd479794..2722441850cc 100644
--- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
+++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
@@ -28,6 +28,7 @@ __be16 sport = 0;
__be32 daddr = 0;
__be16 dport = 0;
int test_exist_lookup = -ENOENT;
+u32 test_exist_lookup_mark = 0;

struct nf_conn;

@@ -174,6 +175,8 @@ nf_ct_test(struct nf_conn *(*lookup_fn)(void *, struct bpf_sock_tuple *, u32,
sizeof(opts_def));
if (ct) {
test_exist_lookup = 0;
+ if (ct->mark == 42)
+ test_exist_lookup_mark = 43;
bpf_ct_release(ct);
} else {
test_exist_lookup = opts_def.error;
--
2.37.1