This builds up on the existing socket cookie test which checks whether the bpf_get_socket_cookie helpers provide the same value in cgroup/connect6 and sockops programs for a socket created by the userspace part of the test. Adding a tracing program to the existing objects requires a different attachment strategy and different headers. Signed-off-by: Florent Revest <revest@xxxxxxxxxxxx> --- .../selftests/bpf/prog_tests/socket_cookie.c | 24 +++++++---- .../selftests/bpf/progs/socket_cookie_prog.c | 41 ++++++++++++++++--- 2 files changed, 52 insertions(+), 13 deletions(-) diff --git a/tools/testing/selftests/bpf/prog_tests/socket_cookie.c b/tools/testing/selftests/bpf/prog_tests/socket_cookie.c index 53d0c44e7907..e5c5e2ea1deb 100644 --- a/tools/testing/selftests/bpf/prog_tests/socket_cookie.c +++ b/tools/testing/selftests/bpf/prog_tests/socket_cookie.c @@ -15,8 +15,8 @@ struct socket_cookie { void test_socket_cookie(void) { + struct bpf_link *set_link, *update_sockops_link, *update_tracing_link; socklen_t addr_len = sizeof(struct sockaddr_in6); - struct bpf_link *set_link, *update_link; int server_fd, client_fd, cgroup_fd; struct socket_cookie_prog *skel; __u32 cookie_expected_value; @@ -39,15 +39,21 @@ void test_socket_cookie(void) PTR_ERR(set_link))) goto close_cgroup_fd; - update_link = bpf_program__attach_cgroup(skel->progs.update_cookie, - cgroup_fd); - if (CHECK(IS_ERR(update_link), "update-link-cg-attach", "err %ld\n", - PTR_ERR(update_link))) + update_sockops_link = bpf_program__attach_cgroup( + skel->progs.update_cookie_sockops, cgroup_fd); + if (CHECK(IS_ERR(update_sockops_link), "update-sockops-link-cg-attach", + "err %ld\n", PTR_ERR(update_sockops_link))) goto free_set_link; + update_tracing_link = bpf_program__attach( + skel->progs.update_cookie_tracing); + if (CHECK(IS_ERR(update_tracing_link), "update-tracing-link-attach", + "err %ld\n", PTR_ERR(update_tracing_link))) + goto free_update_sockops_link; + server_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0); if (CHECK(server_fd < 0, "start_server", "errno %d\n", errno)) - goto free_update_link; + goto free_update_tracing_link; client_fd = connect_to_fd(server_fd, 0); if (CHECK(client_fd < 0, "connect_to_fd", "errno %d\n", errno)) @@ -71,8 +77,10 @@ void test_socket_cookie(void) close(client_fd); close_server_fd: close(server_fd); -free_update_link: - bpf_link__destroy(update_link); +free_update_tracing_link: + bpf_link__destroy(update_tracing_link); +free_update_sockops_link: + bpf_link__destroy(update_sockops_link); free_set_link: bpf_link__destroy(set_link); close_cgroup_fd: diff --git a/tools/testing/selftests/bpf/progs/socket_cookie_prog.c b/tools/testing/selftests/bpf/progs/socket_cookie_prog.c index 81e84be6f86d..1f770b732cb1 100644 --- a/tools/testing/selftests/bpf/progs/socket_cookie_prog.c +++ b/tools/testing/selftests/bpf/progs/socket_cookie_prog.c @@ -1,11 +1,13 @@ // SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2018 Facebook -#include <linux/bpf.h> -#include <sys/socket.h> +#include "vmlinux.h" #include <bpf/bpf_helpers.h> #include <bpf/bpf_endian.h> +#include <bpf/bpf_tracing.h> + +#define AF_INET6 10 struct socket_cookie { __u64 cookie_key; @@ -19,6 +21,14 @@ struct { __type(value, struct socket_cookie); } socket_cookies SEC(".maps"); +/* + * These three programs get executed in a row on connect() syscalls. The + * userspace side of the test creates a client socket, issues a connect() on it + * and then checks that the local storage associated with this socket has: + * cookie_value == local_port << 8 | 0xFF + * The different parts of this cookie_value are appended by those hooks if they + * all agree on the output of bpf_get_socket_cookie(). + */ SEC("cgroup/connect6") int set_cookie(struct bpf_sock_addr *ctx) { @@ -32,14 +42,14 @@ int set_cookie(struct bpf_sock_addr *ctx) if (!p) return 1; - p->cookie_value = 0xFF; + p->cookie_value = 0xF; p->cookie_key = bpf_get_socket_cookie(ctx); return 1; } SEC("sockops") -int update_cookie(struct bpf_sock_ops *ctx) +int update_cookie_sockops(struct bpf_sock_ops *ctx) { struct bpf_sock *sk; struct socket_cookie *p; @@ -60,9 +70,30 @@ int update_cookie(struct bpf_sock_ops *ctx) if (p->cookie_key != bpf_get_socket_cookie(ctx)) return 1; - p->cookie_value = (ctx->local_port << 8) | p->cookie_value; + p->cookie_value |= (ctx->local_port << 8); return 1; } +SEC("fexit/inet_stream_connect") +int BPF_PROG(update_cookie_tracing, struct socket *sock, + struct sockaddr *uaddr, int addr_len, int flags) +{ + struct socket_cookie *p; + + if (uaddr->sa_family != AF_INET6) + return 0; + + p = bpf_sk_storage_get(&socket_cookies, sock->sk, 0, 0); + if (!p) + return 0; + + if (p->cookie_key != bpf_get_socket_cookie(sock->sk)) + return 0; + + p->cookie_value |= 0xF0; + + return 0; +} + char _license[] SEC("license") = "GPL"; -- 2.29.2.576.ga3fc446d84-goog