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