Add read_tcpext_snmp() helper to network_helpers which reads a TcpExt SNMP counter via nstat, and use it in the tcp_custom_syncookie test to verify that LINUX_MIB_SYNCOOKIESRECV is incremented and LINUX_MIB_SYNCOOKIESFAILED stays unchanged across a successful BPF custom syncookie validation.
The delta is captured between start_server() and accept(), which covers the full SYN/ACK/cookie-check path for one connection. Signed-off-by: Jiayuan Chen <[email protected]> Reviewed-by: Kuniyuki Iwashima <[email protected]> --- tools/testing/selftests/bpf/network_helpers.c | 22 +++++++++++++++++++ tools/testing/selftests/bpf/network_helpers.h | 1 + .../bpf/prog_tests/tcp_custom_syncookie.c | 20 +++++++++++++++++ 3 files changed, 43 insertions(+) diff --git a/tools/testing/selftests/bpf/network_helpers.c b/tools/testing/selftests/bpf/network_helpers.c index b82f572641b7d..3388dd5112b6f 100644 --- a/tools/testing/selftests/bpf/network_helpers.c +++ b/tools/testing/selftests/bpf/network_helpers.c @@ -621,6 +621,28 @@ int get_socket_local_port(int sock_fd) return -1; } +int read_tcpext_snmp(const char *name, unsigned long *val) +{ + char cmd[128], buf[128]; + int ret = 0; + FILE *f; + + snprintf(cmd, sizeof(cmd), + "nstat -az TcpExt%s | awk '/TcpExt/ {print $2}'", name); + f = popen(cmd, "r"); + if (!f) + return -errno; + + if (!fgets(buf, sizeof(buf), f)) { + ret = ferror(f) ? -errno : -ENODATA; + goto out; + } + *val = strtoul(buf, NULL, 10); +out: + pclose(f); + return ret; +} + int get_hw_ring_size(char *ifname, struct ethtool_ringparam *ring_param) { struct ifreq ifr = {0}; diff --git a/tools/testing/selftests/bpf/network_helpers.h b/tools/testing/selftests/bpf/network_helpers.h index 79a010c88e11c..c53cd781df6e6 100644 --- a/tools/testing/selftests/bpf/network_helpers.h +++ b/tools/testing/selftests/bpf/network_helpers.h @@ -84,6 +84,7 @@ int make_sockaddr(int family, const char *addr_str, __u16 port, struct sockaddr_storage *addr, socklen_t *len); char *ping_command(int family); int get_socket_local_port(int sock_fd); +int read_tcpext_snmp(const char *name, unsigned long *val); int get_hw_ring_size(char *ifname, struct ethtool_ringparam *ring_param); int set_hw_ring_size(char *ifname, struct ethtool_ringparam *ring_param); diff --git a/tools/testing/selftests/bpf/prog_tests/tcp_custom_syncookie.c b/tools/testing/selftests/bpf/prog_tests/tcp_custom_syncookie.c index eaf441dc7e79b..00d5c32674fc9 100644 --- a/tools/testing/selftests/bpf/prog_tests/tcp_custom_syncookie.c +++ b/tools/testing/selftests/bpf/prog_tests/tcp_custom_syncookie.c @@ -91,12 +91,21 @@ static void transfer_message(int sender, int receiver) static void create_connection(struct test_tcp_custom_syncookie_case *test_case) { + unsigned long failed_before, failed_after; + unsigned long recv_before, recv_after; int server, client, child; server = start_server(test_case->family, test_case->type, test_case->addr, 0, 0); if (!ASSERT_NEQ(server, -1, "start_server")) return; + if (!ASSERT_OK(read_tcpext_snmp("SyncookiesRecv", &recv_before), + "read SyncookiesRecv before")) + goto close_server; + if (!ASSERT_OK(read_tcpext_snmp("SyncookiesFailed", &failed_before), + "read SyncookiesFailed before")) + goto close_server; + client = connect_to_fd(server, 0); if (!ASSERT_NEQ(client, -1, "connect_to_fd")) goto close_server; @@ -105,9 +114,20 @@ static void create_connection(struct test_tcp_custom_syncookie_case *test_case) if (!ASSERT_NEQ(child, -1, "accept")) goto close_client; + if (!ASSERT_OK(read_tcpext_snmp("SyncookiesRecv", &recv_after), + "read SyncookiesRecv after")) + goto close_child; + if (!ASSERT_OK(read_tcpext_snmp("SyncookiesFailed", &failed_after), + "read SyncookiesFailed after")) + goto close_child; + + ASSERT_EQ(recv_after - recv_before, 1, "SyncookiesRecv delta"); + ASSERT_EQ(failed_after - failed_before, 0, "SyncookiesFailed delta"); + transfer_message(client, child); transfer_message(child, client); +close_child: close(child); close_client: close(client); -- 2.43.0
