1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (c) 2020 Facebook */ 3 4 #define _GNU_SOURCE 5 #include <netinet/in.h> 6 #include <arpa/inet.h> 7 #include <unistd.h> 8 #include <stdlib.h> 9 #include <string.h> 10 #include <errno.h> 11 #include <sched.h> 12 #include <net/if.h> 13 #include <linux/compiler.h> 14 #include <bpf/libbpf.h> 15 16 #include "network_helpers.h" 17 #include "test_progs.h" 18 #include "test_btf_skc_cls_ingress.skel.h" 19 20 static struct test_btf_skc_cls_ingress *skel; 21 static struct sockaddr_in6 srv_sa6; 22 static __u32 duration; 23 24 static int prepare_netns(void) 25 { 26 LIBBPF_OPTS(bpf_tc_hook, qdisc_lo, .attach_point = BPF_TC_INGRESS); 27 LIBBPF_OPTS(bpf_tc_opts, tc_attach, 28 .prog_fd = bpf_program__fd(skel->progs.cls_ingress)); 29 30 if (CHECK(unshare(CLONE_NEWNET), "create netns", 31 "unshare(CLONE_NEWNET): %s (%d)", 32 strerror(errno), errno)) 33 return -1; 34 35 if (CHECK(system("ip link set dev lo up"), 36 "ip link set dev lo up", "failed\n")) 37 return -1; 38 39 qdisc_lo.ifindex = if_nametoindex("lo"); 40 if (!ASSERT_OK(bpf_tc_hook_create(&qdisc_lo), "qdisc add dev lo clsact")) 41 return -1; 42 43 if (!ASSERT_OK(bpf_tc_attach(&qdisc_lo, &tc_attach), 44 "filter add dev lo ingress")) 45 return -1; 46 47 /* Ensure 20 bytes options (i.e. in total 40 bytes tcp header) for the 48 * bpf_tcp_gen_syncookie() helper. 49 */ 50 if (write_sysctl("/proc/sys/net/ipv4/tcp_window_scaling", "1") || 51 write_sysctl("/proc/sys/net/ipv4/tcp_timestamps", "1") || 52 write_sysctl("/proc/sys/net/ipv4/tcp_sack", "1")) 53 return -1; 54 55 return 0; 56 } 57 58 static void reset_test(void) 59 { 60 memset(&skel->bss->srv_sa6, 0, sizeof(skel->bss->srv_sa6)); 61 skel->bss->listen_tp_sport = 0; 62 skel->bss->req_sk_sport = 0; 63 skel->bss->recv_cookie = 0; 64 skel->bss->gen_cookie = 0; 65 skel->bss->linum = 0; 66 } 67 68 static void print_err_line(void) 69 { 70 if (skel->bss->linum) 71 printf("bpf prog error at line %u\n", skel->bss->linum); 72 } 73 74 static void test_conn(void) 75 { 76 int listen_fd = -1, cli_fd = -1, srv_fd = -1, err; 77 socklen_t addrlen = sizeof(srv_sa6); 78 int srv_port; 79 80 if (write_sysctl("/proc/sys/net/ipv4/tcp_syncookies", "1")) 81 return; 82 83 listen_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0); 84 if (CHECK_FAIL(listen_fd == -1)) 85 return; 86 87 err = getsockname(listen_fd, (struct sockaddr *)&srv_sa6, &addrlen); 88 if (CHECK(err, "getsockname(listen_fd)", "err:%d errno:%d\n", err, 89 errno)) 90 goto done; 91 memcpy(&skel->bss->srv_sa6, &srv_sa6, sizeof(srv_sa6)); 92 srv_port = ntohs(srv_sa6.sin6_port); 93 94 cli_fd = connect_to_fd(listen_fd, 0); 95 if (CHECK_FAIL(cli_fd == -1)) 96 goto done; 97 98 srv_fd = accept(listen_fd, NULL, NULL); 99 if (CHECK_FAIL(srv_fd == -1)) 100 goto done; 101 102 if (CHECK(skel->bss->listen_tp_sport != srv_port || 103 skel->bss->req_sk_sport != srv_port, 104 "Unexpected sk src port", 105 "listen_tp_sport:%u req_sk_sport:%u expected:%u\n", 106 skel->bss->listen_tp_sport, skel->bss->req_sk_sport, 107 srv_port)) 108 goto done; 109 110 if (CHECK(skel->bss->gen_cookie || skel->bss->recv_cookie, 111 "Unexpected syncookie states", 112 "gen_cookie:%u recv_cookie:%u\n", 113 skel->bss->gen_cookie, skel->bss->recv_cookie)) 114 goto done; 115 116 CHECK(skel->bss->linum, "bpf prog detected error", "at line %u\n", 117 skel->bss->linum); 118 119 done: 120 if (listen_fd != -1) 121 close(listen_fd); 122 if (cli_fd != -1) 123 close(cli_fd); 124 if (srv_fd != -1) 125 close(srv_fd); 126 } 127 128 static void test_syncookie(void) 129 { 130 int listen_fd = -1, cli_fd = -1, srv_fd = -1, err; 131 socklen_t addrlen = sizeof(srv_sa6); 132 int srv_port; 133 134 /* Enforce syncookie mode */ 135 if (write_sysctl("/proc/sys/net/ipv4/tcp_syncookies", "2")) 136 return; 137 138 listen_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0); 139 if (CHECK_FAIL(listen_fd == -1)) 140 return; 141 142 err = getsockname(listen_fd, (struct sockaddr *)&srv_sa6, &addrlen); 143 if (CHECK(err, "getsockname(listen_fd)", "err:%d errno:%d\n", err, 144 errno)) 145 goto done; 146 memcpy(&skel->bss->srv_sa6, &srv_sa6, sizeof(srv_sa6)); 147 srv_port = ntohs(srv_sa6.sin6_port); 148 149 cli_fd = connect_to_fd(listen_fd, 0); 150 if (CHECK_FAIL(cli_fd == -1)) 151 goto done; 152 153 srv_fd = accept(listen_fd, NULL, NULL); 154 if (CHECK_FAIL(srv_fd == -1)) 155 goto done; 156 157 if (CHECK(skel->bss->listen_tp_sport != srv_port, 158 "Unexpected tp src port", 159 "listen_tp_sport:%u expected:%u\n", 160 skel->bss->listen_tp_sport, srv_port)) 161 goto done; 162 163 if (CHECK(skel->bss->req_sk_sport, 164 "Unexpected req_sk src port", 165 "req_sk_sport:%u expected:0\n", 166 skel->bss->req_sk_sport)) 167 goto done; 168 169 if (CHECK(!skel->bss->gen_cookie || 170 skel->bss->gen_cookie != skel->bss->recv_cookie, 171 "Unexpected syncookie states", 172 "gen_cookie:%u recv_cookie:%u\n", 173 skel->bss->gen_cookie, skel->bss->recv_cookie)) 174 goto done; 175 176 CHECK(skel->bss->linum, "bpf prog detected error", "at line %u\n", 177 skel->bss->linum); 178 179 done: 180 if (listen_fd != -1) 181 close(listen_fd); 182 if (cli_fd != -1) 183 close(cli_fd); 184 if (srv_fd != -1) 185 close(srv_fd); 186 } 187 188 struct test { 189 const char *desc; 190 void (*run)(void); 191 }; 192 193 #define DEF_TEST(name) { #name, test_##name } 194 static struct test tests[] = { 195 DEF_TEST(conn), 196 DEF_TEST(syncookie), 197 }; 198 199 void test_btf_skc_cls_ingress(void) 200 { 201 int i; 202 203 skel = test_btf_skc_cls_ingress__open_and_load(); 204 if (CHECK(!skel, "test_btf_skc_cls_ingress__open_and_load", "failed\n")) 205 return; 206 207 for (i = 0; i < ARRAY_SIZE(tests); i++) { 208 if (!test__start_subtest(tests[i].desc)) 209 continue; 210 211 if (prepare_netns()) 212 break; 213 214 tests[i].run(); 215 216 print_err_line(); 217 reset_test(); 218 } 219 220 test_btf_skc_cls_ingress__destroy(skel); 221 } 222