1 /* Check recvmsg/recvmmsg 64-bit timestamp support.
2 Copyright (C) 2022-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19 #include <array_length.h>
20 #include <arpa/inet.h>
21 #include <errno.h>
22 #include <string.h>
23 #include <stdio.h>
24 #include <support/check.h>
25 #include <support/next_to_fault.h>
26 #include <support/support.h>
27 #include <support/test-driver.h>
28 #include <support/xunistd.h>
29 #include <support/xsocket.h>
30 #include <sys/mman.h>
31
32 /* Some extra space added for ancillary data, it might be used to convert
33 32-bit timestamp to 64-bit for _TIME_BITS=64. */
34 enum { slack_max_size = 64 };
35 static const int slack[] = { 0, 4, 8, 16, 32, slack_max_size };
36
37 static bool support_64_timestamp;
38 /* AF_INET socket and address used to receive data. */
39 static int srv;
40 static struct sockaddr_in srv_addr;
41
42 static int
43 do_sendto (const struct sockaddr_in *addr, int nmsgs)
44 {
45 int s = xsocket (AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0);
46 xconnect (s, (const struct sockaddr *) addr, sizeof (*addr));
47
48 for (int i = 0; i < nmsgs; i++)
49 xsendto (s, &i, sizeof (i), 0, (const struct sockaddr *) addr,
50 sizeof (*addr));
51
52 xclose (s);
53
54 return 0;
55 }
56
57 static void
58 do_recvmsg_slack_ancillary (bool use_multi_call, int s, void *cmsg,
59 size_t slack, size_t tsize, int exp_payload)
60 {
61 int payload;
62 struct iovec iov =
63 {
64 .iov_base = &payload,
65 .iov_len = sizeof (payload)
66 };
67 size_t msg_controllen = CMSG_SPACE (tsize) + slack;
68 char *msg_control = cmsg - msg_controllen;
69 memset (msg_control, 0x55, msg_controllen);
70 struct mmsghdr mmhdr =
71 {
72 .msg_hdr =
73 {
74 .msg_name = NULL,
75 .msg_namelen = 0,
76 .msg_iov = &iov,
77 .msg_iovlen = 1,
78 .msg_control = msg_control,
79 .msg_controllen = msg_controllen
80 },
81 };
82
83 int r;
84 if (use_multi_call)
85 {
86 r = recvmmsg (s, &mmhdr, 1, 0, NULL);
87 if (r >= 0)
88 r = mmhdr.msg_len;
89 }
90 else
91 r = recvmsg (s, &mmhdr.msg_hdr, 0);
92 TEST_COMPARE (r, sizeof (int));
93 TEST_COMPARE (payload, exp_payload);
94
95 if (cmsg == NULL)
96 return;
97
98 /* A timestamp is expected if 32-bit timestamp are used (support in every
99 configuration) or if underlying kernel support 64-bit timestamps.
100 Otherwise recvmsg will need extra space do add the 64-bit timestamp. */
101 bool exp_timestamp;
102 if (sizeof (time_t) == 4 || support_64_timestamp)
103 exp_timestamp = true;
104 else
105 exp_timestamp = slack >= CMSG_SPACE (tsize);
106
107 bool timestamp = false;
108 for (struct cmsghdr *cmsg = CMSG_FIRSTHDR (&mmhdr.msg_hdr);
109 cmsg != NULL;
110 cmsg = CMSG_NXTHDR (&mmhdr.msg_hdr, cmsg))
111 {
112 if (cmsg->cmsg_level != SOL_SOCKET)
113 continue;
114 if (cmsg->cmsg_type == SCM_TIMESTAMP
115 && cmsg->cmsg_len == CMSG_LEN (sizeof (struct timeval)))
116 {
117 struct timeval tv;
118 memcpy (&tv, CMSG_DATA (cmsg), sizeof (tv));
119 if (test_verbose)
120 printf ("SCM_TIMESTAMP: {%jd, %jd}\n", (intmax_t)tv.tv_sec,
121 (intmax_t)tv.tv_usec);
122 timestamp = true;
123 }
124 else if (cmsg->cmsg_type == SCM_TIMESTAMPNS
125 && cmsg->cmsg_len == CMSG_LEN (sizeof (struct timespec)))
126 {
127 struct timespec ts;
128 memcpy (&ts, CMSG_DATA (cmsg), sizeof (ts));
129 if (test_verbose)
130 printf ("SCM_TIMESTAMPNS: {%jd, %jd}\n", (intmax_t)ts.tv_sec,
131 (intmax_t)ts.tv_nsec);
132 timestamp = true;
133 }
134 }
135
136 TEST_COMPARE (timestamp, exp_timestamp);
137 }
138
139 /* Check if the extra ancillary space is correctly handled by recvmsg and
140 recvmmsg with different extra space for the ancillaty buffer. */
141 static void
142 do_test_slack_space (void)
143 {
144 /* Setup the ancillary data buffer with an extra page with PROT_NONE to
145 check the possible timestamp conversion on some systems. */
146 struct support_next_to_fault nf =
147 support_next_to_fault_allocate (slack_max_size);
148 void *msgbuf = nf.buffer + slack_max_size;
149
150 /* Enable the timestamp using struct timeval precision. */
151 {
152 int r = setsockopt (srv, SOL_SOCKET, SO_TIMESTAMP, &(int){1},
153 sizeof (int));
154 TEST_VERIFY_EXIT (r != -1);
155 }
156 /* Check recvmsg. */
157 do_sendto (&srv_addr, array_length (slack));
158 for (int s = 0; s < array_length (slack); s++)
159 {
160 memset (nf.buffer, 0x55, nf.length);
161 do_recvmsg_slack_ancillary (false, srv, msgbuf, slack[s],
162 sizeof (struct timeval), s);
163 }
164 /* Check recvmmsg. */
165 do_sendto (&srv_addr, array_length (slack));
166 for (int s = 0; s < array_length (slack); s++)
167 {
168 memset (nf.buffer, 0x55, nf.length);
169 do_recvmsg_slack_ancillary (true, srv, msgbuf, slack[s],
170 sizeof (struct timeval), s);
171 }
172
173 /* Now enable timestamp using a higher precision, it overwrites the previous
174 precision. */
175 {
176 int r = setsockopt (srv, SOL_SOCKET, SO_TIMESTAMPNS, &(int){1},
177 sizeof (int));
178 TEST_VERIFY_EXIT (r != -1);
179 }
180 /* Check recvmsg. */
181 do_sendto (&srv_addr, array_length (slack));
182 for (int s = 0; s < array_length (slack); s++)
183 do_recvmsg_slack_ancillary (false, srv, msgbuf, slack[s],
184 sizeof (struct timespec), s);
185 /* Check recvmmsg. */
186 do_sendto (&srv_addr, array_length (slack));
187 for (int s = 0; s < array_length (slack); s++)
188 do_recvmsg_slack_ancillary (true, srv, msgbuf, slack[s],
189 sizeof (struct timespec), s);
190
191 support_next_to_fault_free (&nf);
192 }
193
194 /* Check if the converted 64-bit timestamp is correctly appended when there
195 are multiple ancillary messages. */
196 static void
197 do_recvmsg_multiple_ancillary (bool use_multi_call, int s, void *cmsg,
198 size_t cmsgsize, int exp_msg)
199 {
200 int msg;
201 struct iovec iov =
202 {
203 .iov_base = &msg,
204 .iov_len = sizeof (msg)
205 };
206 size_t msgs = cmsgsize;
207 struct mmsghdr mmhdr =
208 {
209 .msg_hdr =
210 {
211 .msg_name = NULL,
212 .msg_namelen = 0,
213 .msg_iov = &iov,
214 .msg_iovlen = 1,
215 .msg_controllen = msgs,
216 .msg_control = cmsg,
217 },
218 };
219
220 int r;
221 if (use_multi_call)
222 {
223 r = recvmmsg (s, &mmhdr, 1, 0, NULL);
224 if (r >= 0)
225 r = mmhdr.msg_len;
226 }
227 else
228 r = recvmsg (s, &mmhdr.msg_hdr, 0);
229 TEST_COMPARE (r, sizeof (int));
230 TEST_COMPARE (msg, exp_msg);
231
232 if (cmsg == NULL)
233 return;
234
235 bool timestamp = false;
236 bool origdstaddr = false;
237 for (struct cmsghdr *cmsg = CMSG_FIRSTHDR (&mmhdr.msg_hdr);
238 cmsg != NULL;
239 cmsg = CMSG_NXTHDR (&mmhdr.msg_hdr, cmsg))
240 {
241 if (cmsg->cmsg_level == SOL_IP
242 && cmsg->cmsg_type == IP_ORIGDSTADDR
243 && cmsg->cmsg_len >= CMSG_LEN (sizeof (struct sockaddr_in)))
244 {
245 struct sockaddr_in sa;
246 memcpy (&sa, CMSG_DATA (cmsg), sizeof (sa));
247 if (test_verbose)
248 {
249 char str[INET_ADDRSTRLEN];
250 inet_ntop (AF_INET, &sa.sin_addr, str, INET_ADDRSTRLEN);
251 printf ("IP_ORIGDSTADDR: %s:%d\n", str, ntohs (sa.sin_port));
252 }
253 origdstaddr = sa.sin_addr.s_addr == srv_addr.sin_addr.s_addr
254 && sa.sin_port == srv_addr.sin_port;
255 }
256 if (cmsg->cmsg_level == SOL_SOCKET
257 && cmsg->cmsg_type == SCM_TIMESTAMP
258 && cmsg->cmsg_len >= CMSG_LEN (sizeof (struct timeval)))
259 {
260 struct timeval tv;
261 memcpy (&tv, CMSG_DATA (cmsg), sizeof (tv));
262 if (test_verbose)
263 printf ("SCM_TIMESTAMP: {%jd, %jd}\n", (intmax_t)tv.tv_sec,
264 (intmax_t)tv.tv_usec);
265 timestamp = true;
266 }
267 }
268
269 TEST_COMPARE (timestamp, true);
270 TEST_COMPARE (origdstaddr, true);
271 }
272
273 static void
274 do_test_multiple_ancillary (void)
275 {
276 {
277 int r = setsockopt (srv, SOL_SOCKET, SO_TIMESTAMP, &(int){1},
278 sizeof (int));
279 TEST_VERIFY_EXIT (r != -1);
280 }
281 {
282 int r = setsockopt (srv, IPPROTO_IP, IP_RECVORIGDSTADDR, &(int){1},
283 sizeof (int));
284 TEST_VERIFY_EXIT (r != -1);
285 }
286
287 /* Enough data for default SO_TIMESTAMP, the IP_RECVORIGDSTADDR, and the
288 extra 64-bit SO_TIMESTAMP. */
289 enum { msgbuflen = CMSG_SPACE (2 * sizeof (uint64_t))
290 + CMSG_SPACE (sizeof (struct sockaddr_in))
291 + CMSG_SPACE (2 * sizeof (uint64_t)) };
292 char msgbuf[msgbuflen];
293
294 enum { nmsgs = 8 };
295 /* Check recvmsg. */
296 do_sendto (&srv_addr, nmsgs);
297 for (int s = 0; s < nmsgs; s++)
298 do_recvmsg_multiple_ancillary (false, srv, msgbuf, msgbuflen, s);
299 /* Check recvmmsg. */
300 do_sendto (&srv_addr, nmsgs);
301 for (int s = 0; s < nmsgs; s++)
302 do_recvmsg_multiple_ancillary (true, srv, msgbuf, msgbuflen, s);
303 }
304
305 static int
306 do_test (void)
307 {
308 srv = xsocket (AF_INET, SOCK_DGRAM, 0);
309 srv_addr = (struct sockaddr_in) {
310 .sin_family = AF_INET,
311 .sin_addr = {.s_addr = htonl (INADDR_LOOPBACK) },
312 };
313 xbind (srv, (struct sockaddr *) &srv_addr, sizeof (srv_addr));
314 {
315 socklen_t sa_len = sizeof (srv_addr);
316 xgetsockname (srv, (struct sockaddr *) &srv_addr, &sa_len);
317 TEST_VERIFY (sa_len == sizeof (srv_addr));
318 }
319
320 TEST_COMPARE (recvmsg (-1, NULL, 0), -1);
321 TEST_COMPARE (errno, EBADF);
322 TEST_COMPARE (recvmmsg (-1, NULL, 0, 0, NULL), -1);
323 TEST_COMPARE (errno, EBADF);
324
325 /* If underlying kernel does not support */
326 support_64_timestamp = support_socket_so_timestamp_time64 (srv);
327
328 do_test_slack_space ();
329 do_test_multiple_ancillary ();
330
331 xclose (srv);
332
333 return 0;
334 }
335
336 #include <support/test-driver.c>