[PATCH bpf-next 4/4] selftests/bpf: Add mptcp subflow subtest

From: Matthieu Baerts (NGI0)
Date: Tue May 07 2024 - 06:56:03 EST


From: Geliang Tang <tanggeliang@xxxxxxxxxx>

This patch adds a subtest named test_subflow to load and verify the newly
added mptcp subflow example in test_mptcp. Add a helper endpoint_init()
to add a new subflow endpoint. Add another helper ss_search() to verify the
fwmark and congestion values set by mptcp_subflow prog using setsockopts.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/76
Signed-off-by: Geliang Tang <tanggeliang@xxxxxxxxxx>
Reviewed-by: Mat Martineau <martineau@xxxxxxxxxx>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>
---
tools/testing/selftests/bpf/prog_tests/mptcp.c | 108 +++++++++++++++++++++++++
1 file changed, 108 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/mptcp.c b/tools/testing/selftests/bpf/prog_tests/mptcp.c
index 9d1b255bb654..b1f4b74efd2b 100644
--- a/tools/testing/selftests/bpf/prog_tests/mptcp.c
+++ b/tools/testing/selftests/bpf/prog_tests/mptcp.c
@@ -9,8 +9,12 @@
#include "network_helpers.h"
#include "mptcp_sock.skel.h"
#include "mptcpify.skel.h"
+#include "mptcp_subflow.skel.h"

#define NS_TEST "mptcp_ns"
+#define ADDR_1 "10.0.1.1"
+#define ADDR_2 "10.0.1.2"
+#define PORT_1 10001

#ifndef IPPROTO_MPTCP
#define IPPROTO_MPTCP 262
@@ -347,6 +351,109 @@ static void test_mptcpify(void)
close(cgroup_fd);
}

+static int endpoint_init(char *flags)
+{
+ SYS(fail, "ip -net %s link add veth1 type veth peer name veth2", NS_TEST);
+ SYS(fail, "ip -net %s addr add %s/24 dev veth1", NS_TEST, ADDR_1);
+ SYS(fail, "ip -net %s link set dev veth1 up", NS_TEST);
+ SYS(fail, "ip -net %s addr add %s/24 dev veth2", NS_TEST, ADDR_2);
+ SYS(fail, "ip -net %s link set dev veth2 up", NS_TEST);
+ SYS(fail, "ip -net %s mptcp endpoint add %s %s", NS_TEST, ADDR_2, flags);
+
+ return 0;
+fail:
+ return -1;
+}
+
+static int _ss_search(char *src, char *dst, char *port, char *keyword)
+{
+ char cmd[128];
+ int n;
+
+ n = snprintf(cmd, sizeof(cmd),
+ "ip netns exec %s ss -Menita src %s dst %s %s %d | grep -q '%s'",
+ NS_TEST, src, dst, port, PORT_1, keyword);
+ if (n < 0 || n >= sizeof(cmd))
+ return -1;
+
+ return system(cmd);
+}
+
+static int ss_search(char *src, char *keyword)
+{
+ return _ss_search(src, ADDR_1, "dport", keyword);
+}
+
+static void run_subflow(char *new)
+{
+ int server_fd, client_fd, err;
+ char cc[TCP_CA_NAME_MAX];
+ socklen_t len = sizeof(cc);
+
+ server_fd = start_mptcp_server(AF_INET, ADDR_1, PORT_1, 0);
+ if (!ASSERT_GE(server_fd, 0, "start_mptcp_server"))
+ return;
+
+ client_fd = connect_to_fd(server_fd, 0);
+ if (!ASSERT_GE(client_fd, 0, "connect to fd"))
+ goto fail;
+
+ err = getsockopt(server_fd, SOL_TCP, TCP_CONGESTION, cc, &len);
+ if (!ASSERT_OK(err, "getsockopt(srv_fd, TCP_CONGESTION)"))
+ goto fail;
+
+ send_byte(client_fd);
+
+ ASSERT_OK(ss_search(ADDR_1, "fwmark:0x1"), "ss_search fwmark:0x1");
+ ASSERT_OK(ss_search(ADDR_2, "fwmark:0x2"), "ss_search fwmark:0x2");
+ ASSERT_OK(ss_search(ADDR_1, new), "ss_search new cc");
+ ASSERT_OK(ss_search(ADDR_2, cc), "ss_search default cc");
+
+ close(client_fd);
+fail:
+ close(server_fd);
+}
+
+static void test_subflow(void)
+{
+ int cgroup_fd, prog_fd, err;
+ struct mptcp_subflow *skel;
+ struct nstoken *nstoken;
+
+ cgroup_fd = test__join_cgroup("/mptcp_subflow");
+ if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup: mptcp_subflow"))
+ return;
+
+ skel = mptcp_subflow__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "skel_open_load: mptcp_subflow"))
+ goto close_cgroup;
+
+ err = mptcp_subflow__attach(skel);
+ if (!ASSERT_OK(err, "skel_attach: mptcp_subflow"))
+ goto skel_destroy;
+
+ prog_fd = bpf_program__fd(skel->progs.mptcp_subflow);
+ err = bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_SOCK_OPS, 0);
+ if (!ASSERT_OK(err, "prog_attach"))
+ goto skel_destroy;
+
+ nstoken = create_netns();
+ if (!ASSERT_OK_PTR(nstoken, "create_netns: mptcp_subflow"))
+ goto skel_destroy;
+
+ if (!ASSERT_OK(endpoint_init("subflow"), "endpoint_init"))
+ goto close_netns;
+
+ run_subflow(skel->data->cc);
+
+close_netns:
+ cleanup_netns(nstoken);
+skel_destroy:
+ mptcp_subflow__destroy(skel);
+close_cgroup:
+ close(cgroup_fd);
+}
+
#define RUN_MPTCP_TEST(suffix) \
do { \
if (test__start_subtest(#suffix)) \
@@ -357,4 +464,5 @@ void test_mptcp(void)
{
RUN_MPTCP_TEST(base);
RUN_MPTCP_TEST(mptcpify);
+ RUN_MPTCP_TEST(subflow);
}

--
2.43.0