Implement a new test program mptcpify: if the family is AF_INET or AF_INET6, the type is SOCK_STREAM, and the protocol ID is 0 or IPPROTO_TCP, set it to IPPROTO_MPTCP. It will be hooked in update_socket_protocol().
Extend the MPTCP test base, add a selftest test_mptcpify() for the mptcpify case. Open and load the mptcpify test prog to mptcpify the TCP sockets dynamically, then use start_server() and connect_to_fd() to create a TCP socket, but actually what's created is an MPTCP socket, which can be verified through 'getsockopt(SOL_PROTOCOL)' and 'getsockopt(MPTCP_INFO)'.
Acked-by: Yonghong Song yonghong.song@linux.dev Reviewed-by: Matthieu Baerts matthieu.baerts@tessares.net Signed-off-by: Geliang Tang geliang.tang@suse.com --- .../testing/selftests/bpf/prog_tests/mptcp.c | 116 ++++++++++++++++++ tools/testing/selftests/bpf/progs/mptcpify.c | 20 +++ 2 files changed, 136 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/mptcpify.c
diff --git a/tools/testing/selftests/bpf/prog_tests/mptcp.c b/tools/testing/selftests/bpf/prog_tests/mptcp.c index 3d3999067e27..68ebf9735e16 100644 --- a/tools/testing/selftests/bpf/prog_tests/mptcp.c +++ b/tools/testing/selftests/bpf/prog_tests/mptcp.c @@ -2,13 +2,30 @@ /* Copyright (c) 2020, Tessares SA. */ /* Copyright (c) 2022, SUSE. */
+#include <linux/mptcp.h> +#include <netinet/in.h> #include <test_progs.h> #include "cgroup_helpers.h" #include "network_helpers.h" #include "mptcp_sock.skel.h" +#include "mptcpify.skel.h"
#define NS_TEST "mptcp_ns"
+#ifndef IPPROTO_MPTCP +#define IPPROTO_MPTCP 262 +#endif + +#ifndef MPTCP_INFO +#define MPTCP_INFO 1 +#endif +#ifndef MPTCP_INFO_FLAG_FALLBACK +#define MPTCP_INFO_FLAG_FALLBACK _BITUL(0) +#endif +#ifndef MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED +#define MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED _BITUL(1) +#endif + #ifndef TCP_CA_NAME_MAX #define TCP_CA_NAME_MAX 16 #endif @@ -183,8 +200,107 @@ static void test_base(void) close(cgroup_fd); }
+static void send_byte(int fd) +{ + char b = 0x55; + + ASSERT_EQ(write(fd, &b, sizeof(b)), 1, "send single byte"); +} + +static int verify_mptcpify(int server_fd, int client_fd) +{ + struct mptcp_info info; + socklen_t optlen; + int protocol; + int err = 0; + + optlen = sizeof(protocol); + if (!ASSERT_OK(getsockopt(server_fd, SOL_SOCKET, SO_PROTOCOL, &protocol, &optlen), + "getsockopt(SOL_PROTOCOL)")) + return -1; + + if (!ASSERT_EQ(protocol, IPPROTO_MPTCP, "protocol isn't MPTCP")) + err++; + + optlen = sizeof(info); + if (!ASSERT_OK(getsockopt(client_fd, SOL_MPTCP, MPTCP_INFO, &info, &optlen), + "getsockopt(MPTCP_INFO)")) + return -1; + + if (!ASSERT_GE(info.mptcpi_flags, 0, "unexpected mptcpi_flags")) + err++; + if (!ASSERT_FALSE(info.mptcpi_flags & MPTCP_INFO_FLAG_FALLBACK, + "MPTCP fallback")) + err++; + if (!ASSERT_TRUE(info.mptcpi_flags & MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED, + "no remote key received")) + err++; + + return err; +} + +static int run_mptcpify(int cgroup_fd) +{ + int server_fd, client_fd, err = 0; + struct mptcpify *mptcpify_skel; + + mptcpify_skel = mptcpify__open_and_load(); + if (!ASSERT_OK_PTR(mptcpify_skel, "skel_open_load")) + return libbpf_get_error(mptcpify_skel); + + err = mptcpify__attach(mptcpify_skel); + if (!ASSERT_OK(err, "skel_attach")) + goto out; + + /* without MPTCP */ + server_fd = start_server(AF_INET, SOCK_STREAM, NULL, 0, 0); + if (!ASSERT_GE(server_fd, 0, "start_server")) { + err = -EIO; + goto out; + } + + client_fd = connect_to_fd(server_fd, 0); + if (!ASSERT_GE(client_fd, 0, "connect to fd")) { + err = -EIO; + goto close_server; + } + + send_byte(client_fd); + + err = verify_mptcpify(server_fd, client_fd); + + close(client_fd); +close_server: + close(server_fd); +out: + mptcpify__destroy(mptcpify_skel); + return err; +} + +static void test_mptcpify(void) +{ + struct nstoken *nstoken = NULL; + int cgroup_fd; + + cgroup_fd = test__join_cgroup("/mptcpify"); + if (!ASSERT_GE(cgroup_fd, 0, "test__join_cgroup")) + return; + + nstoken = create_netns(); + if (!ASSERT_OK_PTR(nstoken, "create_netns")) + goto fail; + + ASSERT_OK(run_mptcpify(cgroup_fd), "run_mptcpify"); + +fail: + cleanup_netns(nstoken); + close(cgroup_fd); +} + void test_mptcp(void) { if (test__start_subtest("base")) test_base(); + if (test__start_subtest("mptcpify")) + test_mptcpify(); } diff --git a/tools/testing/selftests/bpf/progs/mptcpify.c b/tools/testing/selftests/bpf/progs/mptcpify.c new file mode 100644 index 000000000000..53301ae8a8f7 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/mptcpify.c @@ -0,0 +1,20 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023, SUSE. */ + +#include "vmlinux.h" +#include <bpf/bpf_tracing.h> +#include "bpf_tracing_net.h" + +char _license[] SEC("license") = "GPL"; + +SEC("fmod_ret/update_socket_protocol") +int BPF_PROG(mptcpify, int family, int type, int protocol) +{ + if ((family == AF_INET || family == AF_INET6) && + type == SOCK_STREAM && + (!protocol || protocol == IPPROTO_TCP)) { + return IPPROTO_MPTCP; + } + + return protocol; +}