1 // SPDX-License-Identifier: GPL-2.0 2 #include <test_progs.h> 3 #include "cgroup_helpers.h" 4 #include "network_helpers.h" 5 #include "tcp_rtt.skel.h" 6 7 struct tcp_rtt_storage { 8 __u32 invoked; 9 __u32 dsack_dups; 10 __u32 delivered; 11 __u32 delivered_ce; 12 __u32 icsk_retransmits; 13 }; 14 15 static void send_byte(int fd) 16 { 17 char b = 0x55; 18 19 if (CHECK_FAIL(write(fd, &b, sizeof(b)) != 1)) 20 perror("Failed to send single byte"); 21 } 22 23 static int wait_for_ack(int fd, int retries) 24 { 25 struct tcp_info info; 26 socklen_t optlen; 27 int i, err; 28 29 for (i = 0; i < retries; i++) { 30 optlen = sizeof(info); 31 err = getsockopt(fd, SOL_TCP, TCP_INFO, &info, &optlen); 32 if (err < 0) { 33 log_err("Failed to lookup TCP stats"); 34 return err; 35 } 36 37 if (info.tcpi_unacked == 0) 38 return 0; 39 40 usleep(10); 41 } 42 43 log_err("Did not receive ACK"); 44 return -1; 45 } 46 47 static int verify_sk(int map_fd, int client_fd, const char *msg, __u32 invoked, 48 __u32 dsack_dups, __u32 delivered, __u32 delivered_ce, 49 __u32 icsk_retransmits) 50 { 51 int err = 0; 52 struct tcp_rtt_storage val; 53 54 if (CHECK_FAIL(bpf_map_lookup_elem(map_fd, &client_fd, &val) < 0)) { 55 perror("Failed to read socket storage"); 56 return -1; 57 } 58 59 if (val.invoked != invoked) { 60 log_err("%s: unexpected bpf_tcp_sock.invoked %d != %d", 61 msg, val.invoked, invoked); 62 err++; 63 } 64 65 if (val.dsack_dups != dsack_dups) { 66 log_err("%s: unexpected bpf_tcp_sock.dsack_dups %d != %d", 67 msg, val.dsack_dups, dsack_dups); 68 err++; 69 } 70 71 if (val.delivered != delivered) { 72 log_err("%s: unexpected bpf_tcp_sock.delivered %d != %d", 73 msg, val.delivered, delivered); 74 err++; 75 } 76 77 if (val.delivered_ce != delivered_ce) { 78 log_err("%s: unexpected bpf_tcp_sock.delivered_ce %d != %d", 79 msg, val.delivered_ce, delivered_ce); 80 err++; 81 } 82 83 if (val.icsk_retransmits != icsk_retransmits) { 84 log_err("%s: unexpected bpf_tcp_sock.icsk_retransmits %d != %d", 85 msg, val.icsk_retransmits, icsk_retransmits); 86 err++; 87 } 88 89 return err; 90 } 91 92 93 static int run_test(int cgroup_fd, int server_fd) 94 { 95 struct tcp_rtt *skel; 96 int client_fd; 97 int prog_fd; 98 int map_fd; 99 int err; 100 101 skel = tcp_rtt__open_and_load(); 102 if (!ASSERT_OK_PTR(skel, "skel_open_load")) 103 return -1; 104 105 map_fd = bpf_map__fd(skel->maps.socket_storage_map); 106 prog_fd = bpf_program__fd(skel->progs._sockops); 107 108 err = bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_SOCK_OPS, 0); 109 if (err) { 110 log_err("Failed to attach BPF program"); 111 goto close_bpf_object; 112 } 113 114 client_fd = connect_to_fd(server_fd, 0); 115 if (client_fd < 0) { 116 err = -1; 117 goto close_bpf_object; 118 } 119 120 err += verify_sk(map_fd, client_fd, "syn-ack", 121 /*invoked=*/1, 122 /*dsack_dups=*/0, 123 /*delivered=*/1, 124 /*delivered_ce=*/0, 125 /*icsk_retransmits=*/0); 126 127 send_byte(client_fd); 128 if (wait_for_ack(client_fd, 100) < 0) { 129 err = -1; 130 goto close_client_fd; 131 } 132 133 134 err += verify_sk(map_fd, client_fd, "first payload byte", 135 /*invoked=*/2, 136 /*dsack_dups=*/0, 137 /*delivered=*/2, 138 /*delivered_ce=*/0, 139 /*icsk_retransmits=*/0); 140 141 close_client_fd: 142 close(client_fd); 143 144 close_bpf_object: 145 tcp_rtt__destroy(skel); 146 return err; 147 } 148 149 void test_tcp_rtt(void) 150 { 151 int server_fd, cgroup_fd; 152 153 cgroup_fd = test__join_cgroup("/tcp_rtt"); 154 if (CHECK_FAIL(cgroup_fd < 0)) 155 return; 156 157 server_fd = start_server(AF_INET, SOCK_STREAM, NULL, 0, 0); 158 if (CHECK_FAIL(server_fd < 0)) 159 goto close_cgroup_fd; 160 161 CHECK_FAIL(run_test(cgroup_fd, server_fd)); 162 163 close(server_fd); 164 165 close_cgroup_fd: 166 close(cgroup_fd); 167 } 168