180 lines · c
1// SPDX-License-Identifier: GPL-2.02#define _GNU_SOURCE3#include <test_progs.h>4#include "cgroup_helpers.h"5#include "network_helpers.h"6#include "tcp_rtt.skel.h"7 8struct tcp_rtt_storage {9 __u32 invoked;10 __u32 dsack_dups;11 __u32 delivered;12 __u32 delivered_ce;13 __u32 icsk_retransmits;14 15 __u32 mrtt_us; /* args[0] */16 __u32 srtt; /* args[1] */17};18 19static void send_byte(int fd)20{21 char b = 0x55;22 23 ASSERT_EQ(write(fd, &b, sizeof(b)), 1, "send single byte");24}25 26static int wait_for_ack(int fd, int retries)27{28 struct tcp_info info;29 socklen_t optlen;30 int i, err;31 32 for (i = 0; i < retries; i++) {33 optlen = sizeof(info);34 err = getsockopt(fd, SOL_TCP, TCP_INFO, &info, &optlen);35 if (err < 0) {36 log_err("Failed to lookup TCP stats");37 return err;38 }39 40 if (info.tcpi_unacked == 0)41 return 0;42 43 usleep(10);44 }45 46 log_err("Did not receive ACK");47 return -1;48}49 50static int verify_sk(int map_fd, int client_fd, const char *msg, __u32 invoked,51 __u32 dsack_dups, __u32 delivered, __u32 delivered_ce,52 __u32 icsk_retransmits)53{54 int err = 0;55 struct tcp_rtt_storage val;56 57 if (!ASSERT_GE(bpf_map_lookup_elem(map_fd, &client_fd, &val), 0, "read socket storage"))58 return -1;59 60 if (val.invoked != invoked) {61 log_err("%s: unexpected bpf_tcp_sock.invoked %d != %d",62 msg, val.invoked, invoked);63 err++;64 }65 66 if (val.dsack_dups != dsack_dups) {67 log_err("%s: unexpected bpf_tcp_sock.dsack_dups %d != %d",68 msg, val.dsack_dups, dsack_dups);69 err++;70 }71 72 if (val.delivered != delivered) {73 log_err("%s: unexpected bpf_tcp_sock.delivered %d != %d",74 msg, val.delivered, delivered);75 err++;76 }77 78 if (val.delivered_ce != delivered_ce) {79 log_err("%s: unexpected bpf_tcp_sock.delivered_ce %d != %d",80 msg, val.delivered_ce, delivered_ce);81 err++;82 }83 84 if (val.icsk_retransmits != icsk_retransmits) {85 log_err("%s: unexpected bpf_tcp_sock.icsk_retransmits %d != %d",86 msg, val.icsk_retransmits, icsk_retransmits);87 err++;88 }89 90 /* Precise values of mrtt and srtt are unavailable, just make sure they are nonzero */91 if (val.mrtt_us == 0) {92 log_err("%s: unexpected bpf_tcp_sock.args[0] (mrtt_us) %u == 0", msg, val.mrtt_us);93 err++;94 }95 96 if (val.srtt == 0) {97 log_err("%s: unexpected bpf_tcp_sock.args[1] (srtt) %u == 0", msg, val.srtt);98 err++;99 }100 101 return err;102}103 104 105static int run_test(int cgroup_fd, int server_fd)106{107 struct tcp_rtt *skel;108 int client_fd;109 int prog_fd;110 int map_fd;111 int err;112 113 skel = tcp_rtt__open_and_load();114 if (!ASSERT_OK_PTR(skel, "skel_open_load"))115 return -1;116 117 map_fd = bpf_map__fd(skel->maps.socket_storage_map);118 prog_fd = bpf_program__fd(skel->progs._sockops);119 120 err = bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_SOCK_OPS, 0);121 if (err) {122 log_err("Failed to attach BPF program");123 goto close_bpf_object;124 }125 126 client_fd = connect_to_fd(server_fd, 0);127 if (client_fd < 0) {128 err = -1;129 goto close_bpf_object;130 }131 132 err += verify_sk(map_fd, client_fd, "syn-ack",133 /*invoked=*/1,134 /*dsack_dups=*/0,135 /*delivered=*/1,136 /*delivered_ce=*/0,137 /*icsk_retransmits=*/0);138 139 send_byte(client_fd);140 if (wait_for_ack(client_fd, 100) < 0) {141 err = -1;142 goto close_client_fd;143 }144 145 146 err += verify_sk(map_fd, client_fd, "first payload byte",147 /*invoked=*/2,148 /*dsack_dups=*/0,149 /*delivered=*/2,150 /*delivered_ce=*/0,151 /*icsk_retransmits=*/0);152 153close_client_fd:154 close(client_fd);155 156close_bpf_object:157 tcp_rtt__destroy(skel);158 return err;159}160 161void test_tcp_rtt(void)162{163 int server_fd, cgroup_fd;164 165 cgroup_fd = test__join_cgroup("/tcp_rtt");166 if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup /tcp_rtt"))167 return;168 169 server_fd = start_server(AF_INET, SOCK_STREAM, NULL, 0, 0);170 if (!ASSERT_GE(server_fd, 0, "start_server"))171 goto close_cgroup_fd;172 173 ASSERT_OK(run_test(cgroup_fd, server_fd), "run_test");174 175 close(server_fd);176 177close_cgroup_fd:178 close(cgroup_fd);179}180