1 // SPDX-License-Identifier: GPL-2.0 2 #define _GNU_SOURCE 3 #include <test_progs.h> 4 #include "cgroup_helpers.h" 5 #include "network_helpers.h" 6 #include "tcp_rtt.skel.h" 7 8 struct tcp_rtt_storage { 9 __u32 invoked; 10 __u32 dsack_dups; 11 __u32 delivered; 12 __u32 delivered_ce; 13 __u32 icsk_retransmits; 14 }; 15 16 static void send_byte(int fd) 17 { 18 char b = 0x55; 19 20 ASSERT_EQ(write(fd, &b, sizeof(b)), 1, "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 (!ASSERT_GE(bpf_map_lookup_elem(map_fd, &client_fd, &val), 0, "read socket storage")) 55 return -1; 56 57 if (val.invoked != invoked) { 58 log_err("%s: unexpected bpf_tcp_sock.invoked %d != %d", 59 msg, val.invoked, invoked); 60 err++; 61 } 62 63 if (val.dsack_dups != dsack_dups) { 64 log_err("%s: unexpected bpf_tcp_sock.dsack_dups %d != %d", 65 msg, val.dsack_dups, dsack_dups); 66 err++; 67 } 68 69 if (val.delivered != delivered) { 70 log_err("%s: unexpected bpf_tcp_sock.delivered %d != %d", 71 msg, val.delivered, delivered); 72 err++; 73 } 74 75 if (val.delivered_ce != delivered_ce) { 76 log_err("%s: unexpected bpf_tcp_sock.delivered_ce %d != %d", 77 msg, val.delivered_ce, delivered_ce); 78 err++; 79 } 80 81 if (val.icsk_retransmits != icsk_retransmits) { 82 log_err("%s: unexpected bpf_tcp_sock.icsk_retransmits %d != %d", 83 msg, val.icsk_retransmits, icsk_retransmits); 84 err++; 85 } 86 87 return err; 88 } 89 90 91 static int run_test(int cgroup_fd, int server_fd) 92 { 93 struct tcp_rtt *skel; 94 int client_fd; 95 int prog_fd; 96 int map_fd; 97 int err; 98 99 skel = tcp_rtt__open_and_load(); 100 if (!ASSERT_OK_PTR(skel, "skel_open_load")) 101 return -1; 102 103 map_fd = bpf_map__fd(skel->maps.socket_storage_map); 104 prog_fd = bpf_program__fd(skel->progs._sockops); 105 106 err = bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_SOCK_OPS, 0); 107 if (err) { 108 log_err("Failed to attach BPF program"); 109 goto close_bpf_object; 110 } 111 112 client_fd = connect_to_fd(server_fd, 0); 113 if (client_fd < 0) { 114 err = -1; 115 goto close_bpf_object; 116 } 117 118 err += verify_sk(map_fd, client_fd, "syn-ack", 119 /*invoked=*/1, 120 /*dsack_dups=*/0, 121 /*delivered=*/1, 122 /*delivered_ce=*/0, 123 /*icsk_retransmits=*/0); 124 125 send_byte(client_fd); 126 if (wait_for_ack(client_fd, 100) < 0) { 127 err = -1; 128 goto close_client_fd; 129 } 130 131 132 err += verify_sk(map_fd, client_fd, "first payload byte", 133 /*invoked=*/2, 134 /*dsack_dups=*/0, 135 /*delivered=*/2, 136 /*delivered_ce=*/0, 137 /*icsk_retransmits=*/0); 138 139 close_client_fd: 140 close(client_fd); 141 142 close_bpf_object: 143 tcp_rtt__destroy(skel); 144 return err; 145 } 146 147 void test_tcp_rtt(void) 148 { 149 int server_fd, cgroup_fd; 150 151 cgroup_fd = test__join_cgroup("/tcp_rtt"); 152 if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup /tcp_rtt")) 153 return; 154 155 server_fd = start_server(AF_INET, SOCK_STREAM, NULL, 0, 0); 156 if (!ASSERT_GE(server_fd, 0, "start_server")) 157 goto close_cgroup_fd; 158 159 ASSERT_OK(run_test(cgroup_fd, server_fd), "run_test"); 160 161 close(server_fd); 162 163 close_cgroup_fd: 164 close(cgroup_fd); 165 } 166