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
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
|
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2023 Facebook */
#include <test_progs.h>
#include <linux/in6.h>
#include <sys/socket.h>
#include <sched.h>
#include <unistd.h>
#include "cgroup_helpers.h"
#include "testing_helpers.h"
#include "cgroup_tcp_skb.skel.h"
#include "cgroup_tcp_skb.h"
#include "network_helpers.h"
#define CGROUP_TCP_SKB_PATH "/test_cgroup_tcp_skb"
static int install_filters(int cgroup_fd,
struct bpf_link **egress_link,
struct bpf_link **ingress_link,
struct bpf_program *egress_prog,
struct bpf_program *ingress_prog,
struct cgroup_tcp_skb *skel)
{
/* Prepare filters */
skel->bss->g_sock_state = 0;
skel->bss->g_unexpected = 0;
*egress_link =
bpf_program__attach_cgroup(egress_prog,
cgroup_fd);
if (!ASSERT_OK_PTR(egress_link, "egress_link"))
return -1;
*ingress_link =
bpf_program__attach_cgroup(ingress_prog,
cgroup_fd);
if (!ASSERT_OK_PTR(ingress_link, "ingress_link"))
return -1;
return 0;
}
static void uninstall_filters(struct bpf_link **egress_link,
struct bpf_link **ingress_link)
{
bpf_link__destroy(*egress_link);
*egress_link = NULL;
bpf_link__destroy(*ingress_link);
*ingress_link = NULL;
}
static int create_client_sock_v6(void)
{
int fd;
fd = socket(AF_INET6, SOCK_STREAM, 0);
if (fd < 0) {
perror("socket");
return -1;
}
return fd;
}
/* Connect to the server in a cgroup from the outside of the cgroup. */
static int talk_to_cgroup(int *client_fd, int *listen_fd, int *service_fd,
struct cgroup_tcp_skb *skel)
{
int err, cp;
char buf[5];
int port;
/* Create client & server socket */
err = join_root_cgroup();
if (!ASSERT_OK(err, "join_root_cgroup"))
return -1;
*client_fd = create_client_sock_v6();
if (!ASSERT_GE(*client_fd, 0, "client_fd"))
return -1;
err = join_cgroup(CGROUP_TCP_SKB_PATH);
if (!ASSERT_OK(err, "join_cgroup"))
return -1;
*listen_fd = start_server(AF_INET6, SOCK_STREAM, NULL, 0, 0);
if (!ASSERT_GE(*listen_fd, 0, "listen_fd"))
return -1;
port = get_socket_local_port(*listen_fd);
if (!ASSERT_GE(port, 0, "get_socket_local_port"))
return -1;
skel->bss->g_sock_port = ntohs(port);
/* Connect client to server */
err = connect_fd_to_fd(*client_fd, *listen_fd, 0);
if (!ASSERT_OK(err, "connect_fd_to_fd"))
return -1;
*service_fd = accept(*listen_fd, NULL, NULL);
if (!ASSERT_GE(*service_fd, 0, "service_fd"))
return -1;
err = join_root_cgroup();
if (!ASSERT_OK(err, "join_root_cgroup"))
return -1;
cp = write(*client_fd, "hello", 5);
if (!ASSERT_EQ(cp, 5, "write"))
return -1;
cp = read(*service_fd, buf, 5);
if (!ASSERT_EQ(cp, 5, "read"))
return -1;
return 0;
}
/* Connect to the server out of a cgroup from inside the cgroup. */
static int talk_to_outside(int *client_fd, int *listen_fd, int *service_fd,
struct cgroup_tcp_skb *skel)
{
int err, cp;
char buf[5];
int port;
/* Create client & server socket */
err = join_root_cgroup();
if (!ASSERT_OK(err, "join_root_cgroup"))
return -1;
*listen_fd = start_server(AF_INET6, SOCK_STREAM, NULL, 0, 0);
if (!ASSERT_GE(*listen_fd, 0, "listen_fd"))
return -1;
err = join_cgroup(CGROUP_TCP_SKB_PATH);
if (!ASSERT_OK(err, "join_cgroup"))
return -1;
*client_fd = create_client_sock_v6();
if (!ASSERT_GE(*client_fd, 0, "client_fd"))
return -1;
err = join_root_cgroup();
if (!ASSERT_OK(err, "join_root_cgroup"))
return -1;
port = get_socket_local_port(*listen_fd);
if (!ASSERT_GE(port, 0, "get_socket_local_port"))
return -1;
skel->bss->g_sock_port = ntohs(port);
/* Connect client to server */
err = connect_fd_to_fd(*client_fd, *listen_fd, 0);
if (!ASSERT_OK(err, "connect_fd_to_fd"))
return -1;
*service_fd = accept(*listen_fd, NULL, NULL);
if (!ASSERT_GE(*service_fd, 0, "service_fd"))
return -1;
cp = write(*client_fd, "hello", 5);
if (!ASSERT_EQ(cp, 5, "write"))
return -1;
cp = read(*service_fd, buf, 5);
if (!ASSERT_EQ(cp, 5, "read"))
return -1;
return 0;
}
static int close_connection(int *closing_fd, int *peer_fd, int *listen_fd,
struct cgroup_tcp_skb *skel)
{
__u32 saved_packet_count = 0;
int err;
int i;
/* Wait for ACKs to be sent */
saved_packet_count = skel->bss->g_packet_count;
usleep(100000); /* 0.1s */
for (i = 0;
skel->bss->g_packet_count != saved_packet_count && i < 10;
i++) {
saved_packet_count = skel->bss->g_packet_count;
usleep(100000); /* 0.1s */
}
if (!ASSERT_EQ(skel->bss->g_packet_count, saved_packet_count,
"packet_count"))
return -1;
skel->bss->g_packet_count = 0;
saved_packet_count = 0;
/* Half shutdown to make sure the closing socket having a chance to
* receive a FIN from the peer.
*/
err = shutdown(*closing_fd, SHUT_WR);
if (!ASSERT_OK(err, "shutdown closing_fd"))
return -1;
/* Wait for FIN and the ACK of the FIN to be observed */
for (i = 0;
skel->bss->g_packet_count < saved_packet_count + 2 && i < 10;
i++)
usleep(100000); /* 0.1s */
if (!ASSERT_GE(skel->bss->g_packet_count, saved_packet_count + 2,
"packet_count"))
return -1;
saved_packet_count = skel->bss->g_packet_count;
/* Fully shutdown the connection */
err = close(*peer_fd);
if (!ASSERT_OK(err, "close peer_fd"))
return -1;
*peer_fd = -1;
/* Wait for FIN and the ACK of the FIN to be observed */
for (i = 0;
skel->bss->g_packet_count < saved_packet_count + 2 && i < 10;
i++)
usleep(100000); /* 0.1s */
if (!ASSERT_GE(skel->bss->g_packet_count, saved_packet_count + 2,
"packet_count"))
return -1;
err = close(*closing_fd);
if (!ASSERT_OK(err, "close closing_fd"))
return -1;
*closing_fd = -1;
close(*listen_fd);
*listen_fd = -1;
return 0;
}
/* This test case includes four scenarios:
* 1. Connect to the server from outside the cgroup and close the connection
* from outside the cgroup.
* 2. Connect to the server from outside the cgroup and close the connection
* from inside the cgroup.
* 3. Connect to the server from inside the cgroup and close the connection
* from outside the cgroup.
* 4. Connect to the server from inside the cgroup and close the connection
* from inside the cgroup.
*
* The test case is to verify that cgroup_skb/{egress,ingress} filters
* receive expected packets including SYN, SYN/ACK, ACK, FIN, and FIN/ACK.
*/
void test_cgroup_tcp_skb(void)
{
struct bpf_link *ingress_link = NULL;
struct bpf_link *egress_link = NULL;
int client_fd = -1, listen_fd = -1;
struct cgroup_tcp_skb *skel;
int service_fd = -1;
int cgroup_fd = -1;
int err;
skel = cgroup_tcp_skb__open_and_load();
if (!ASSERT_OK(!skel, "skel_open_load"))
return;
err = setup_cgroup_environment();
if (!ASSERT_OK(err, "setup_cgroup_environment"))
goto cleanup;
cgroup_fd = create_and_get_cgroup(CGROUP_TCP_SKB_PATH);
if (!ASSERT_GE(cgroup_fd, 0, "cgroup_fd"))
goto cleanup;
/* Scenario 1 */
err = install_filters(cgroup_fd, &egress_link, &ingress_link,
skel->progs.server_egress,
skel->progs.server_ingress,
skel);
if (!ASSERT_OK(err, "install_filters"))
goto cleanup;
err = talk_to_cgroup(&client_fd, &listen_fd, &service_fd, skel);
if (!ASSERT_OK(err, "talk_to_cgroup"))
goto cleanup;
err = close_connection(&client_fd, &service_fd, &listen_fd, skel);
if (!ASSERT_OK(err, "close_connection"))
goto cleanup;
ASSERT_EQ(skel->bss->g_unexpected, 0, "g_unexpected");
ASSERT_EQ(skel->bss->g_sock_state, CLOSED, "g_sock_state");
uninstall_filters(&egress_link, &ingress_link);
/* Scenario 2 */
err = install_filters(cgroup_fd, &egress_link, &ingress_link,
skel->progs.server_egress_srv,
skel->progs.server_ingress_srv,
skel);
err = talk_to_cgroup(&client_fd, &listen_fd, &service_fd, skel);
if (!ASSERT_OK(err, "talk_to_cgroup"))
goto cleanup;
err = close_connection(&service_fd, &client_fd, &listen_fd, skel);
if (!ASSERT_OK(err, "close_connection"))
goto cleanup;
ASSERT_EQ(skel->bss->g_unexpected, 0, "g_unexpected");
ASSERT_EQ(skel->bss->g_sock_state, TIME_WAIT, "g_sock_state");
uninstall_filters(&egress_link, &ingress_link);
/* Scenario 3 */
err = install_filters(cgroup_fd, &egress_link, &ingress_link,
skel->progs.client_egress_srv,
skel->progs.client_ingress_srv,
skel);
err = talk_to_outside(&client_fd, &listen_fd, &service_fd, skel);
if (!ASSERT_OK(err, "talk_to_outside"))
goto cleanup;
err = close_connection(&service_fd, &client_fd, &listen_fd, skel);
if (!ASSERT_OK(err, "close_connection"))
goto cleanup;
ASSERT_EQ(skel->bss->g_unexpected, 0, "g_unexpected");
ASSERT_EQ(skel->bss->g_sock_state, CLOSED, "g_sock_state");
uninstall_filters(&egress_link, &ingress_link);
/* Scenario 4 */
err = install_filters(cgroup_fd, &egress_link, &ingress_link,
skel->progs.client_egress,
skel->progs.client_ingress,
skel);
err = talk_to_outside(&client_fd, &listen_fd, &service_fd, skel);
if (!ASSERT_OK(err, "talk_to_outside"))
goto cleanup;
err = close_connection(&client_fd, &service_fd, &listen_fd, skel);
if (!ASSERT_OK(err, "close_connection"))
goto cleanup;
ASSERT_EQ(skel->bss->g_unexpected, 0, "g_unexpected");
ASSERT_EQ(skel->bss->g_sock_state, TIME_WAIT, "g_sock_state");
uninstall_filters(&egress_link, &ingress_link);
cleanup:
close(client_fd);
close(listen_fd);
close(service_fd);
close(cgroup_fd);
bpf_link__destroy(egress_link);
bpf_link__destroy(ingress_link);
cleanup_cgroup_environment();
cgroup_tcp_skb__destroy(skel);
}
|
