selftests/bpf: add tcx netns cookie tests

JIRA: https://issues.redhat.com/browse/RHEL-110279

commit 693fe95
Author: Mahe Tardy <mahe.tardy@gmail.com>
Date:   Mon Oct 7 09:59:58 2024 +0000

    selftests/bpf: add tcx netns cookie tests

    Add netns cookie test that verifies the helper is now supported and work
    in the context of tc programs.

    Signed-off-by: Mahe Tardy <mahe.tardy@gmail.com>
    Link: https://lore.kernel.org/r/20241007095958.97442-2-mahe.tardy@gmail.com
    Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

Signed-off-by: Jerome Marchand <jmarchan@redhat.com>

Author: jeromemarchand

tools/testing/selftests/bpf/prog_tests/netns_cookie.c

@@ -8,12 +8,16 @@
 #define SO_NETNS_COOKIE 71
 #endif
 
+#define loopback 1
+
 static int duration;
 
 void test_netns_cookie(void)
 {
+	LIBBPF_OPTS(bpf_prog_attach_opts, opta);
+	LIBBPF_OPTS(bpf_prog_detach_opts, optd);
 	int server_fd = -1, client_fd = -1, cgroup_fd = -1;
-	int err, val, ret, map, verdict;
+	int err, val, ret, map, verdict, tc_fd;
 	struct netns_cookie_prog *skel;
 	uint64_t cookie_expected_value;
 	socklen_t vallen = sizeof(cookie_expected_value);
@@ -38,36 +42,47 @@ void test_netns_cookie(void)
 	if (!ASSERT_OK(err, "prog_attach"))
 		goto done;
 
+	tc_fd = bpf_program__fd(skel->progs.get_netns_cookie_tcx);
+	err = bpf_prog_attach_opts(tc_fd, loopback, BPF_TCX_INGRESS, &opta);
+	if (!ASSERT_OK(err, "prog_attach"))
+		goto done;
+
 	server_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0);
 	if (CHECK(server_fd < 0, "start_server", "errno %d\n", errno))
-		goto done;
+		goto cleanup_tc;
 
 	client_fd = connect_to_fd(server_fd, 0);
 	if (CHECK(client_fd < 0, "connect_to_fd", "errno %d\n", errno))
-		goto done;
+		goto cleanup_tc;
 
 	ret = send(client_fd, send_msg, sizeof(send_msg), 0);
 	if (CHECK(ret != sizeof(send_msg), "send(msg)", "ret:%d\n", ret))
-		goto done;
+		goto cleanup_tc;
 
 	err = bpf_map_lookup_elem(bpf_map__fd(skel->maps.sockops_netns_cookies),
 				  &client_fd, &val);
 	if (!ASSERT_OK(err, "map_lookup(sockops_netns_cookies)"))
-		goto done;
+		goto cleanup_tc;
 
 	err = getsockopt(client_fd, SOL_SOCKET, SO_NETNS_COOKIE,
 			 &cookie_expected_value, &vallen);
 	if (!ASSERT_OK(err, "getsockopt"))
-		goto done;
+		goto cleanup_tc;
 
 	ASSERT_EQ(val, cookie_expected_value, "cookie_value");
 
 	err = bpf_map_lookup_elem(bpf_map__fd(skel->maps.sk_msg_netns_cookies),
 				  &client_fd, &val);
 	if (!ASSERT_OK(err, "map_lookup(sk_msg_netns_cookies)"))
-		goto done;
+		goto cleanup_tc;
 
 	ASSERT_EQ(val, cookie_expected_value, "cookie_value");
+	ASSERT_EQ(skel->bss->tcx_init_netns_cookie, cookie_expected_value, "cookie_value");
+	ASSERT_EQ(skel->bss->tcx_netns_cookie, cookie_expected_value, "cookie_value");
+
+cleanup_tc:
+	err = bpf_prog_detach_opts(tc_fd, loopback, BPF_TCX_INGRESS, &optd);
+	ASSERT_OK(err, "prog_detach");
 
 done:
 	if (server_fd != -1)

tools/testing/selftests/bpf/progs/netns_cookie_prog.c

@@ -27,6 +27,8 @@ struct {
 	__type(value, __u64);
 } sock_map SEC(".maps");
 
+int tcx_init_netns_cookie, tcx_netns_cookie;
+
 SEC("sockops")
 int get_netns_cookie_sockops(struct bpf_sock_ops *ctx)
 {
@@ -81,4 +83,12 @@ int get_netns_cookie_sk_msg(struct sk_msg_md *msg)
 	return 1;
 }
 
+SEC("tcx/ingress")
+int get_netns_cookie_tcx(struct __sk_buff *skb)
+{
+	tcx_init_netns_cookie = bpf_get_netns_cookie(NULL);
+	tcx_netns_cookie = bpf_get_netns_cookie(skb);
+	return TCX_PASS;
+}
+
 char _license[] SEC("license") = "GPL";