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 <linux/compiler.h>
13 #include <bpf/libbpf.h>
14
15 #include "network_helpers.h"
16 #include "test_progs.h"
17 #include "test_btf_skc_cls_ingress.skel.h"
18
19 static struct test_btf_skc_cls_ingress *skel;
20 static struct sockaddr_in6 srv_sa6;
21 static __u32 duration;
22
23 #define PROG_PIN_FILE "/sys/fs/bpf/btf_skc_cls_ingress"
24
prepare_netns(void)25 static int prepare_netns(void)
26 {
27 if (CHECK(unshare(CLONE_NEWNET), "create netns",
28 "unshare(CLONE_NEWNET): %s (%d)",
29 strerror(errno), errno))
30 return -1;
31
32 if (CHECK(system("ip link set dev lo up"),
33 "ip link set dev lo up", "failed\n"))
34 return -1;
35
36 if (CHECK(system("tc qdisc add dev lo clsact"),
37 "tc qdisc add dev lo clsact", "failed\n"))
38 return -1;
39
40 if (CHECK(system("tc filter add dev lo ingress bpf direct-action object-pinned " PROG_PIN_FILE),
41 "install tc cls-prog at ingress", "failed\n"))
42 return -1;
43
44 /* Ensure 20 bytes options (i.e. in total 40 bytes tcp header) for the
45 * bpf_tcp_gen_syncookie() helper.
46 */
47 if (write_sysctl("/proc/sys/net/ipv4/tcp_window_scaling", "1") ||
48 write_sysctl("/proc/sys/net/ipv4/tcp_timestamps", "1") ||
49 write_sysctl("/proc/sys/net/ipv4/tcp_sack", "1"))
50 return -1;
51
52 return 0;
53 }
54
reset_test(void)55 static void reset_test(void)
56 {
57 memset(&skel->bss->srv_sa6, 0, sizeof(skel->bss->srv_sa6));
58 skel->bss->listen_tp_sport = 0;
59 skel->bss->req_sk_sport = 0;
60 skel->bss->recv_cookie = 0;
61 skel->bss->gen_cookie = 0;
62 skel->bss->linum = 0;
63 }
64
print_err_line(void)65 static void print_err_line(void)
66 {
67 if (skel->bss->linum)
68 printf("bpf prog error at line %u\n", skel->bss->linum);
69 }
70
test_conn(void)71 static void test_conn(void)
72 {
73 int listen_fd = -1, cli_fd = -1, srv_fd = -1, err;
74 socklen_t addrlen = sizeof(srv_sa6);
75 int srv_port;
76
77 if (write_sysctl("/proc/sys/net/ipv4/tcp_syncookies", "1"))
78 return;
79
80 listen_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0);
81 if (CHECK_FAIL(listen_fd == -1))
82 return;
83
84 err = getsockname(listen_fd, (struct sockaddr *)&srv_sa6, &addrlen);
85 if (CHECK(err, "getsockname(listen_fd)", "err:%d errno:%d\n", err,
86 errno))
87 goto done;
88 memcpy(&skel->bss->srv_sa6, &srv_sa6, sizeof(srv_sa6));
89 srv_port = ntohs(srv_sa6.sin6_port);
90
91 cli_fd = connect_to_fd(listen_fd, 0);
92 if (CHECK_FAIL(cli_fd == -1))
93 goto done;
94
95 srv_fd = accept(listen_fd, NULL, NULL);
96 if (CHECK_FAIL(srv_fd == -1))
97 goto done;
98
99 if (CHECK(skel->bss->listen_tp_sport != srv_port ||
100 skel->bss->req_sk_sport != srv_port,
101 "Unexpected sk src port",
102 "listen_tp_sport:%u req_sk_sport:%u expected:%u\n",
103 skel->bss->listen_tp_sport, skel->bss->req_sk_sport,
104 srv_port))
105 goto done;
106
107 if (CHECK(skel->bss->gen_cookie || skel->bss->recv_cookie,
108 "Unexpected syncookie states",
109 "gen_cookie:%u recv_cookie:%u\n",
110 skel->bss->gen_cookie, skel->bss->recv_cookie))
111 goto done;
112
113 CHECK(skel->bss->linum, "bpf prog detected error", "at line %u\n",
114 skel->bss->linum);
115
116 done:
117 if (listen_fd != -1)
118 close(listen_fd);
119 if (cli_fd != -1)
120 close(cli_fd);
121 if (srv_fd != -1)
122 close(srv_fd);
123 }
124
test_syncookie(void)125 static void test_syncookie(void)
126 {
127 int listen_fd = -1, cli_fd = -1, srv_fd = -1, err;
128 socklen_t addrlen = sizeof(srv_sa6);
129 int srv_port;
130
131 /* Enforce syncookie mode */
132 if (write_sysctl("/proc/sys/net/ipv4/tcp_syncookies", "2"))
133 return;
134
135 listen_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0);
136 if (CHECK_FAIL(listen_fd == -1))
137 return;
138
139 err = getsockname(listen_fd, (struct sockaddr *)&srv_sa6, &addrlen);
140 if (CHECK(err, "getsockname(listen_fd)", "err:%d errno:%d\n", err,
141 errno))
142 goto done;
143 memcpy(&skel->bss->srv_sa6, &srv_sa6, sizeof(srv_sa6));
144 srv_port = ntohs(srv_sa6.sin6_port);
145
146 cli_fd = connect_to_fd(listen_fd, 0);
147 if (CHECK_FAIL(cli_fd == -1))
148 goto done;
149
150 srv_fd = accept(listen_fd, NULL, NULL);
151 if (CHECK_FAIL(srv_fd == -1))
152 goto done;
153
154 if (CHECK(skel->bss->listen_tp_sport != srv_port,
155 "Unexpected tp src port",
156 "listen_tp_sport:%u expected:%u\n",
157 skel->bss->listen_tp_sport, srv_port))
158 goto done;
159
160 if (CHECK(skel->bss->req_sk_sport,
161 "Unexpected req_sk src port",
162 "req_sk_sport:%u expected:0\n",
163 skel->bss->req_sk_sport))
164 goto done;
165
166 if (CHECK(!skel->bss->gen_cookie ||
167 skel->bss->gen_cookie != skel->bss->recv_cookie,
168 "Unexpected syncookie states",
169 "gen_cookie:%u recv_cookie:%u\n",
170 skel->bss->gen_cookie, skel->bss->recv_cookie))
171 goto done;
172
173 CHECK(skel->bss->linum, "bpf prog detected error", "at line %u\n",
174 skel->bss->linum);
175
176 done:
177 if (listen_fd != -1)
178 close(listen_fd);
179 if (cli_fd != -1)
180 close(cli_fd);
181 if (srv_fd != -1)
182 close(srv_fd);
183 }
184
185 struct test {
186 const char *desc;
187 void (*run)(void);
188 };
189
190 #define DEF_TEST(name) { #name, test_##name }
191 static struct test tests[] = {
192 DEF_TEST(conn),
193 DEF_TEST(syncookie),
194 };
195
test_btf_skc_cls_ingress(void)196 void test_btf_skc_cls_ingress(void)
197 {
198 int i, err;
199
200 skel = test_btf_skc_cls_ingress__open_and_load();
201 if (CHECK(!skel, "test_btf_skc_cls_ingress__open_and_load", "failed\n"))
202 return;
203
204 err = bpf_program__pin(skel->progs.cls_ingress, PROG_PIN_FILE);
205 if (CHECK(err, "bpf_program__pin",
206 "cannot pin bpf prog to %s. err:%d\n", PROG_PIN_FILE, err)) {
207 test_btf_skc_cls_ingress__destroy(skel);
208 return;
209 }
210
211 for (i = 0; i < ARRAY_SIZE(tests); i++) {
212 if (!test__start_subtest(tests[i].desc))
213 continue;
214
215 if (prepare_netns())
216 break;
217
218 tests[i].run();
219
220 print_err_line();
221 reset_test();
222 }
223
224 bpf_program__unpin(skel->progs.cls_ingress, PROG_PIN_FILE);
225 test_btf_skc_cls_ingress__destroy(skel);
226 }
227
