From 8039d353217c1d9dae921f131cfe4153bc23e960 Mon Sep 17 00:00:00 2001 From: Nicolas Rybowski Date: Thu, 19 May 2022 16:30:12 -0700 Subject: [PATCH] selftests/bpf: Add MPTCP test base This patch adds a base for MPTCP specific tests. It is currently limited to the is_mptcp field in case of plain TCP connection because there is no easy way to get the subflow sk from a msk in userspace. This implies that we cannot lookup the sk_storage attached to the subflow sk in the sockops program. v4: - add copyright 2022 (Andrii) - use ASSERT_* instead of CHECK_FAIL (Andrii) - drop SEC("version") (Andrii) - use is_mptcp in tcp_sock, instead of bpf_tcp_sock (Martin & Andrii) v5: - Drop connect_to_mptcp_fd (Martin) - Use BPF test skeleton (Andrii) - Use ASSERT_EQ (Andrii) - Drop the 'msg' parameter of verify_sk Co-developed-by: Geliang Tang Signed-off-by: Geliang Tang Signed-off-by: Nicolas Rybowski Signed-off-by: Mat Martineau Signed-off-by: Andrii Nakryiko Acked-by: Matthieu Baerts Link: https://lore.kernel.org/bpf/20220519233016.105670-4-mathew.j.martineau@linux.intel.com --- MAINTAINERS | 1 + tools/testing/selftests/bpf/bpf_tcp_helpers.h | 1 + tools/testing/selftests/bpf/config | 1 + tools/testing/selftests/bpf/network_helpers.c | 40 +++++-- tools/testing/selftests/bpf/network_helpers.h | 2 + .../testing/selftests/bpf/prog_tests/mptcp.c | 112 ++++++++++++++++++ .../testing/selftests/bpf/progs/mptcp_sock.c | 53 +++++++++ 7 files changed, 201 insertions(+), 9 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/mptcp.c create mode 100644 tools/testing/selftests/bpf/progs/mptcp_sock.c diff --git a/MAINTAINERS b/MAINTAINERS index cc5559a7fb5c..359afc617b92 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -13780,6 +13780,7 @@ F: include/net/mptcp.h F: include/trace/events/mptcp.h F: include/uapi/linux/mptcp.h F: net/mptcp/ +F: tools/testing/selftests/bpf/*/*mptcp*.c F: tools/testing/selftests/net/mptcp/ NETWORKING [TCP] diff --git a/tools/testing/selftests/bpf/bpf_tcp_helpers.h b/tools/testing/selftests/bpf/bpf_tcp_helpers.h index b1ede6f0b821..22e0c8849a17 100644 --- a/tools/testing/selftests/bpf/bpf_tcp_helpers.h +++ b/tools/testing/selftests/bpf/bpf_tcp_helpers.h @@ -81,6 +81,7 @@ struct tcp_sock { __u32 lsndtime; __u32 prior_cwnd; __u64 tcp_mstamp; /* most recent packet received/sent */ + bool is_mptcp; } __attribute__((preserve_access_index)); static __always_inline struct inet_connection_sock *inet_csk(const struct sock *sk) diff --git a/tools/testing/selftests/bpf/config b/tools/testing/selftests/bpf/config index 6840d4625e01..3b3edc0fc8a6 100644 --- a/tools/testing/selftests/bpf/config +++ b/tools/testing/selftests/bpf/config @@ -56,3 +56,4 @@ CONFIG_USERFAULTFD=y CONFIG_FPROBE=y CONFIG_IKCONFIG=y CONFIG_IKCONFIG_PROC=y +CONFIG_MPTCP=y diff --git a/tools/testing/selftests/bpf/network_helpers.c b/tools/testing/selftests/bpf/network_helpers.c index 2bb1f9b3841d..59cf81ec55af 100644 --- a/tools/testing/selftests/bpf/network_helpers.c +++ b/tools/testing/selftests/bpf/network_helpers.c @@ -21,6 +21,10 @@ #include "network_helpers.h" #include "test_progs.h" +#ifndef IPPROTO_MPTCP +#define IPPROTO_MPTCP 262 +#endif + #define clean_errno() (errno == 0 ? "None" : strerror(errno)) #define log_err(MSG, ...) ({ \ int __save = errno; \ @@ -73,13 +77,13 @@ int settimeo(int fd, int timeout_ms) #define save_errno_close(fd) ({ int __save = errno; close(fd); errno = __save; }) -static int __start_server(int type, const struct sockaddr *addr, +static int __start_server(int type, int protocol, const struct sockaddr *addr, socklen_t addrlen, int timeout_ms, bool reuseport) { int on = 1; int fd; - fd = socket(addr->sa_family, type, 0); + fd = socket(addr->sa_family, type, protocol); if (fd < 0) { log_err("Failed to create server socket"); return -1; @@ -113,8 +117,8 @@ error_close: return -1; } -int start_server(int family, int type, const char *addr_str, __u16 port, - int timeout_ms) +static int start_server_proto(int family, int type, int protocol, + const char *addr_str, __u16 port, int timeout_ms) { struct sockaddr_storage addr; socklen_t addrlen; @@ -122,10 +126,23 @@ int start_server(int family, int type, const char *addr_str, __u16 port, if (make_sockaddr(family, addr_str, port, &addr, &addrlen)) return -1; - return __start_server(type, (struct sockaddr *)&addr, + return __start_server(type, protocol, (struct sockaddr *)&addr, addrlen, timeout_ms, false); } +int start_server(int family, int type, const char *addr_str, __u16 port, + int timeout_ms) +{ + return start_server_proto(family, type, 0, addr_str, port, timeout_ms); +} + +int start_mptcp_server(int family, const char *addr_str, __u16 port, + int timeout_ms) +{ + return start_server_proto(family, SOCK_STREAM, IPPROTO_MPTCP, addr_str, + port, timeout_ms); +} + int *start_reuseport_server(int family, int type, const char *addr_str, __u16 port, int timeout_ms, unsigned int nr_listens) { @@ -144,7 +161,7 @@ int *start_reuseport_server(int family, int type, const char *addr_str, if (!fds) return NULL; - fds[0] = __start_server(type, (struct sockaddr *)&addr, addrlen, + fds[0] = __start_server(type, 0, (struct sockaddr *)&addr, addrlen, timeout_ms, true); if (fds[0] == -1) goto close_fds; @@ -154,7 +171,7 @@ int *start_reuseport_server(int family, int type, const char *addr_str, goto close_fds; for (; nr_fds < nr_listens; nr_fds++) { - fds[nr_fds] = __start_server(type, (struct sockaddr *)&addr, + fds[nr_fds] = __start_server(type, 0, (struct sockaddr *)&addr, addrlen, timeout_ms, true); if (fds[nr_fds] == -1) goto close_fds; @@ -247,7 +264,7 @@ int connect_to_fd_opts(int server_fd, const struct network_helper_opts *opts) struct sockaddr_storage addr; struct sockaddr_in *addr_in; socklen_t addrlen, optlen; - int fd, type; + int fd, type, protocol; if (!opts) opts = &default_opts; @@ -258,6 +275,11 @@ int connect_to_fd_opts(int server_fd, const struct network_helper_opts *opts) return -1; } + if (getsockopt(server_fd, SOL_SOCKET, SO_PROTOCOL, &protocol, &optlen)) { + log_err("getsockopt(SOL_PROTOCOL)"); + return -1; + } + addrlen = sizeof(addr); if (getsockname(server_fd, (struct sockaddr *)&addr, &addrlen)) { log_err("Failed to get server addr"); @@ -265,7 +287,7 @@ int connect_to_fd_opts(int server_fd, const struct network_helper_opts *opts) } addr_in = (struct sockaddr_in *)&addr; - fd = socket(addr_in->sin_family, type, 0); + fd = socket(addr_in->sin_family, type, protocol); if (fd < 0) { log_err("Failed to create client socket"); return -1; diff --git a/tools/testing/selftests/bpf/network_helpers.h b/tools/testing/selftests/bpf/network_helpers.h index a4b3b2f9877b..f882c691b790 100644 --- a/tools/testing/selftests/bpf/network_helpers.h +++ b/tools/testing/selftests/bpf/network_helpers.h @@ -42,6 +42,8 @@ extern struct ipv6_packet pkt_v6; int settimeo(int fd, int timeout_ms); int start_server(int family, int type, const char *addr, __u16 port, int timeout_ms); +int start_mptcp_server(int family, const char *addr, __u16 port, + int timeout_ms); int *start_reuseport_server(int family, int type, const char *addr_str, __u16 port, int timeout_ms, unsigned int nr_listens); diff --git a/tools/testing/selftests/bpf/prog_tests/mptcp.c b/tools/testing/selftests/bpf/prog_tests/mptcp.c new file mode 100644 index 000000000000..6b346e303b90 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/mptcp.c @@ -0,0 +1,112 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020, Tessares SA. */ +/* Copyright (c) 2022, SUSE. */ + +#include +#include "cgroup_helpers.h" +#include "network_helpers.h" +#include "mptcp_sock.skel.h" + +struct mptcp_storage { + __u32 invoked; + __u32 is_mptcp; +}; + +static int verify_sk(int map_fd, int client_fd, __u32 is_mptcp) +{ + int err, cfd = client_fd; + struct mptcp_storage val; + + if (is_mptcp == 1) + return 0; + + err = bpf_map_lookup_elem(map_fd, &cfd, &val); + if (!ASSERT_OK(err, "bpf_map_lookup_elem")) + return err; + + if (!ASSERT_EQ(val.invoked, 1, "unexpected invoked count")) + err++; + + if (!ASSERT_EQ(val.is_mptcp, 0, "unexpected is_mptcp")) + err++; + + return err; +} + +static int run_test(int cgroup_fd, int server_fd, bool is_mptcp) +{ + int client_fd, prog_fd, map_fd, err; + struct mptcp_sock *sock_skel; + + sock_skel = mptcp_sock__open_and_load(); + if (!ASSERT_OK_PTR(sock_skel, "skel_open_load")) + return -EIO; + + prog_fd = bpf_program__fd(sock_skel->progs._sockops); + if (!ASSERT_GE(prog_fd, 0, "bpf_program__fd")) { + err = -EIO; + goto out; + } + + map_fd = bpf_map__fd(sock_skel->maps.socket_storage_map); + if (!ASSERT_GE(map_fd, 0, "bpf_map__fd")) { + err = -EIO; + goto out; + } + + err = bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_SOCK_OPS, 0); + if (!ASSERT_OK(err, "bpf_prog_attach")) + goto out; + + client_fd = connect_to_fd(server_fd, 0); + if (!ASSERT_GE(client_fd, 0, "connect to fd")) { + err = -EIO; + goto out; + } + + err += is_mptcp ? verify_sk(map_fd, client_fd, 1) : + verify_sk(map_fd, client_fd, 0); + + close(client_fd); + +out: + mptcp_sock__destroy(sock_skel); + return err; +} + +static void test_base(void) +{ + int server_fd, cgroup_fd; + + cgroup_fd = test__join_cgroup("/mptcp"); + if (!ASSERT_GE(cgroup_fd, 0, "test__join_cgroup")) + return; + + /* without MPTCP */ + server_fd = start_server(AF_INET, SOCK_STREAM, NULL, 0, 0); + if (!ASSERT_GE(server_fd, 0, "start_server")) + goto with_mptcp; + + ASSERT_OK(run_test(cgroup_fd, server_fd, false), "run_test tcp"); + + close(server_fd); + +with_mptcp: + /* with MPTCP */ + server_fd = start_mptcp_server(AF_INET, NULL, 0, 0); + if (!ASSERT_GE(server_fd, 0, "start_mptcp_server")) + goto close_cgroup_fd; + + ASSERT_OK(run_test(cgroup_fd, server_fd, true), "run_test mptcp"); + + close(server_fd); + +close_cgroup_fd: + close(cgroup_fd); +} + +void test_mptcp(void) +{ + if (test__start_subtest("base")) + test_base(); +} diff --git a/tools/testing/selftests/bpf/progs/mptcp_sock.c b/tools/testing/selftests/bpf/progs/mptcp_sock.c new file mode 100644 index 000000000000..bc09dba0b078 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/mptcp_sock.c @@ -0,0 +1,53 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020, Tessares SA. */ +/* Copyright (c) 2022, SUSE. */ + +#include +#include +#include "bpf_tcp_helpers.h" + +char _license[] SEC("license") = "GPL"; + +struct mptcp_storage { + __u32 invoked; + __u32 is_mptcp; +}; + +struct { + __uint(type, BPF_MAP_TYPE_SK_STORAGE); + __uint(map_flags, BPF_F_NO_PREALLOC); + __type(key, int); + __type(value, struct mptcp_storage); +} socket_storage_map SEC(".maps"); + +SEC("sockops") +int _sockops(struct bpf_sock_ops *ctx) +{ + struct mptcp_storage *storage; + int op = (int)ctx->op; + struct tcp_sock *tsk; + struct bpf_sock *sk; + bool is_mptcp; + + if (op != BPF_SOCK_OPS_TCP_CONNECT_CB) + return 1; + + sk = ctx->sk; + if (!sk) + return 1; + + tsk = bpf_skc_to_tcp_sock(sk); + if (!tsk) + return 1; + + is_mptcp = bpf_core_field_exists(tsk->is_mptcp) ? tsk->is_mptcp : 0; + storage = bpf_sk_storage_get(&socket_storage_map, sk, 0, + BPF_SK_STORAGE_GET_F_CREATE); + if (!storage) + return 1; + + storage->invoked++; + storage->is_mptcp = is_mptcp; + + return 1; +}