1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
|
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2018 Facebook
// Copyright (c) 2019 Cloudflare
#include <limits.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <bpf/bpf.h>
#include <bpf/libbpf.h>
#include "bpf_rlimit.h"
#include "cgroup_helpers.h"
static int start_server(const struct sockaddr *addr, socklen_t len)
{
int fd;
fd = socket(addr->sa_family, SOCK_STREAM, 0);
if (fd == -1) {
log_err("Failed to create server socket");
goto out;
}
if (bind(fd, addr, len) == -1) {
log_err("Failed to bind server socket");
goto close_out;
}
if (listen(fd, 128) == -1) {
log_err("Failed to listen on server socket");
goto close_out;
}
goto out;
close_out:
close(fd);
fd = -1;
out:
return fd;
}
static int connect_to_server(int server_fd)
{
struct sockaddr_storage addr;
socklen_t len = sizeof(addr);
int fd = -1;
if (getsockname(server_fd, (struct sockaddr *)&addr, &len)) {
log_err("Failed to get server addr");
goto out;
}
fd = socket(addr.ss_family, SOCK_STREAM, 0);
if (fd == -1) {
log_err("Failed to create client socket");
goto out;
}
if (connect(fd, (const struct sockaddr *)&addr, len) == -1) {
log_err("Fail to connect to server");
goto close_out;
}
goto out;
close_out:
close(fd);
fd = -1;
out:
return fd;
}
static int get_map_fd_by_prog_id(int prog_id, bool *xdp)
{
struct bpf_prog_info info = {};
__u32 info_len = sizeof(info);
__u32 map_ids[1];
int prog_fd = -1;
int map_fd = -1;
prog_fd = bpf_prog_get_fd_by_id(prog_id);
if (prog_fd < 0) {
log_err("Failed to get fd by prog id %d", prog_id);
goto err;
}
info.nr_map_ids = 1;
info.map_ids = (__u64)(unsigned long)map_ids;
if (bpf_obj_get_info_by_fd(prog_fd, &info, &info_len)) {
log_err("Failed to get info by prog fd %d", prog_fd);
goto err;
}
if (!info.nr_map_ids) {
log_err("No maps found for prog fd %d", prog_fd);
goto err;
}
*xdp = info.type == BPF_PROG_TYPE_XDP;
map_fd = bpf_map_get_fd_by_id(map_ids[0]);
if (map_fd < 0)
log_err("Failed to get fd by map id %d", map_ids[0]);
err:
if (prog_fd >= 0)
close(prog_fd);
return map_fd;
}
static int run_test(int server_fd, int results_fd, bool xdp)
{
int client = -1, srv_client = -1;
int ret = 0;
__u32 key = 0;
__u32 key_gen = 1;
__u32 key_mss = 2;
__u32 value = 0;
__u32 value_gen = 0;
__u32 value_mss = 0;
if (bpf_map_update_elem(results_fd, &key, &value, 0) < 0) {
log_err("Can't clear results");
goto err;
}
if (bpf_map_update_elem(results_fd, &key_gen, &value_gen, 0) < 0) {
log_err("Can't clear results");
goto err;
}
if (bpf_map_update_elem(results_fd, &key_mss, &value_mss, 0) < 0) {
log_err("Can't clear results");
goto err;
}
client = connect_to_server(server_fd);
if (client == -1)
goto err;
srv_client = accept(server_fd, NULL, 0);
if (srv_client == -1) {
log_err("Can't accept connection");
goto err;
}
if (bpf_map_lookup_elem(results_fd, &key, &value) < 0) {
log_err("Can't lookup result");
goto err;
}
if (value == 0) {
log_err("Didn't match syncookie: %u", value);
goto err;
}
if (bpf_map_lookup_elem(results_fd, &key_gen, &value_gen) < 0) {
log_err("Can't lookup result");
goto err;
}
if (xdp && value_gen == 0) {
// SYN packets do not get passed through generic XDP, skip the
// rest of the test.
printf("Skipping XDP cookie check\n");
goto out;
}
if (bpf_map_lookup_elem(results_fd, &key_mss, &value_mss) < 0) {
log_err("Can't lookup result");
goto err;
}
if (value != value_gen) {
log_err("BPF generated cookie does not match kernel one");
goto err;
}
if (value_mss < 536 || value_mss > USHRT_MAX) {
log_err("Unexpected MSS retrieved");
goto err;
}
goto out;
err:
ret = 1;
out:
close(client);
close(srv_client);
return ret;
}
int main(int argc, char **argv)
{
struct sockaddr_in addr4;
struct sockaddr_in6 addr6;
int server = -1;
int server_v6 = -1;
int results = -1;
int err = 0;
bool xdp;
if (argc < 2) {
fprintf(stderr, "Usage: %s prog_id\n", argv[0]);
exit(1);
}
results = get_map_fd_by_prog_id(atoi(argv[1]), &xdp);
if (results < 0) {
log_err("Can't get map");
goto err;
}
memset(&addr4, 0, sizeof(addr4));
addr4.sin_family = AF_INET;
addr4.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
addr4.sin_port = 0;
memset(&addr6, 0, sizeof(addr6));
addr6.sin6_family = AF_INET6;
addr6.sin6_addr = in6addr_loopback;
addr6.sin6_port = 0;
server = start_server((const struct sockaddr *)&addr4, sizeof(addr4));
if (server == -1)
goto err;
server_v6 = start_server((const struct sockaddr *)&addr6,
sizeof(addr6));
if (server_v6 == -1)
goto err;
if (run_test(server, results, xdp))
goto err;
if (run_test(server_v6, results, xdp))
goto err;
printf("ok\n");
goto out;
err:
err = 1;
out:
close(server);
close(server_v6);
close(results);
return err;
}
|
