Commit | Line | Data |
---|---|---|
0d37f2bc DG |
1 | /* |
2 | * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca> | |
3 | * Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License, version 2 only, | |
7 | * as published by the Free Software Foundation. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, but WITHOUT | |
10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
12 | * more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License along | |
15 | * with this program; if not, write to the Free Software Foundation, Inc., | |
16 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. | |
17 | */ | |
18 | ||
19 | #define _GNU_SOURCE | |
20 | #include <assert.h> | |
21 | #include <limits.h> | |
22 | #include <stdio.h> | |
23 | #include <stdlib.h> | |
24 | #include <string.h> | |
25 | #include <sys/stat.h> | |
26 | #include <sys/types.h> | |
27 | #include <unistd.h> | |
28 | #include <errno.h> | |
29 | ||
90e535ef | 30 | #include <common/common.h> |
0d37f2bc DG |
31 | |
32 | #include "unix.h" | |
33 | ||
34 | /* | |
35 | * Connect to unix socket using the path name. | |
36 | */ | |
90e535ef | 37 | LTTNG_HIDDEN |
0d37f2bc DG |
38 | int lttcomm_connect_unix_sock(const char *pathname) |
39 | { | |
40 | struct sockaddr_un sun; | |
41 | int fd, ret, closeret; | |
42 | ||
43 | fd = socket(PF_UNIX, SOCK_STREAM, 0); | |
44 | if (fd < 0) { | |
45 | PERROR("socket"); | |
46 | ret = fd; | |
47 | goto error; | |
48 | } | |
49 | ||
50 | memset(&sun, 0, sizeof(sun)); | |
51 | sun.sun_family = AF_UNIX; | |
52 | strncpy(sun.sun_path, pathname, sizeof(sun.sun_path)); | |
53 | sun.sun_path[sizeof(sun.sun_path) - 1] = '\0'; | |
54 | ||
55 | ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun)); | |
56 | if (ret < 0) { | |
57 | /* | |
58 | * Don't print message on connect error, because connect is used in | |
59 | * normal execution to detect if sessiond is alive. | |
60 | */ | |
61 | goto error_connect; | |
62 | } | |
63 | ||
64 | return fd; | |
65 | ||
66 | error_connect: | |
67 | closeret = close(fd); | |
68 | if (closeret) { | |
69 | PERROR("close"); | |
70 | } | |
71 | error: | |
72 | return ret; | |
73 | } | |
74 | ||
75 | /* | |
76 | * Do an accept(2) on the sock and return the new file descriptor. The socket | |
77 | * MUST be bind(2) before. | |
78 | */ | |
90e535ef | 79 | LTTNG_HIDDEN |
0d37f2bc DG |
80 | int lttcomm_accept_unix_sock(int sock) |
81 | { | |
82 | int new_fd; | |
83 | struct sockaddr_un sun; | |
84 | socklen_t len = 0; | |
85 | ||
86 | /* Blocking call */ | |
87 | new_fd = accept(sock, (struct sockaddr *) &sun, &len); | |
88 | if (new_fd < 0) { | |
89 | PERROR("accept"); | |
90 | } | |
91 | ||
92 | return new_fd; | |
93 | } | |
94 | ||
95 | /* | |
96 | * Creates a AF_UNIX local socket using pathname bind the socket upon creation | |
97 | * and return the fd. | |
98 | */ | |
90e535ef | 99 | LTTNG_HIDDEN |
0d37f2bc DG |
100 | int lttcomm_create_unix_sock(const char *pathname) |
101 | { | |
102 | struct sockaddr_un sun; | |
103 | int fd; | |
104 | int ret = -1; | |
105 | ||
106 | /* Create server socket */ | |
107 | if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) { | |
108 | PERROR("socket"); | |
109 | goto error; | |
110 | } | |
111 | ||
112 | memset(&sun, 0, sizeof(sun)); | |
113 | sun.sun_family = AF_UNIX; | |
114 | strncpy(sun.sun_path, pathname, sizeof(sun.sun_path)); | |
115 | sun.sun_path[sizeof(sun.sun_path) - 1] = '\0'; | |
116 | ||
117 | /* Unlink the old file if present */ | |
118 | (void) unlink(pathname); | |
119 | ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun)); | |
120 | if (ret < 0) { | |
121 | PERROR("bind"); | |
122 | goto error; | |
123 | } | |
124 | ||
125 | return fd; | |
126 | ||
127 | error: | |
17e75273 DG |
128 | if (fd >= 0) { |
129 | if (close(fd) < 0) { | |
130 | PERROR("close create unix sock"); | |
131 | } | |
132 | } | |
0d37f2bc DG |
133 | return ret; |
134 | } | |
135 | ||
136 | /* | |
137 | * Make the socket listen using LTTNG_SESSIOND_COMM_MAX_LISTEN. | |
138 | */ | |
90e535ef | 139 | LTTNG_HIDDEN |
0d37f2bc DG |
140 | int lttcomm_listen_unix_sock(int sock) |
141 | { | |
142 | int ret; | |
143 | ||
144 | ret = listen(sock, LTTNG_SESSIOND_COMM_MAX_LISTEN); | |
145 | if (ret < 0) { | |
146 | PERROR("listen"); | |
147 | } | |
148 | ||
149 | return ret; | |
150 | } | |
151 | ||
152 | /* | |
153 | * Receive data of size len in put that data into the buf param. Using recvmsg | |
154 | * API. | |
155 | * | |
156 | * Return the size of received data. | |
157 | */ | |
90e535ef | 158 | LTTNG_HIDDEN |
0d37f2bc DG |
159 | ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len) |
160 | { | |
161 | struct msghdr msg; | |
162 | struct iovec iov[1]; | |
163 | ssize_t ret = -1; | |
7c5aef62 | 164 | size_t len_last; |
0d37f2bc DG |
165 | |
166 | memset(&msg, 0, sizeof(msg)); | |
167 | ||
168 | iov[0].iov_base = buf; | |
169 | iov[0].iov_len = len; | |
170 | msg.msg_iov = iov; | |
171 | msg.msg_iovlen = 1; | |
172 | ||
173 | do { | |
7c5aef62 DG |
174 | len_last = iov[0].iov_len; |
175 | ret = recvmsg(sock, &msg, 0); | |
176 | if (ret > 0) { | |
177 | iov[0].iov_base += ret; | |
178 | iov[0].iov_len -= ret; | |
179 | assert(ret <= len_last); | |
180 | } | |
181 | } while ((ret > 0 && ret < len_last) || (ret < 0 && errno == EINTR)); | |
0d37f2bc DG |
182 | if (ret < 0) { |
183 | PERROR("recvmsg"); | |
7c5aef62 DG |
184 | } else if (ret > 0) { |
185 | ret = len; | |
0d37f2bc | 186 | } |
7c5aef62 | 187 | /* Else ret = 0 meaning an orderly shutdown. */ |
0d37f2bc DG |
188 | |
189 | return ret; | |
190 | } | |
191 | ||
192 | /* | |
193 | * Send buf data of size len. Using sendmsg API. | |
194 | * | |
195 | * Return the size of sent data. | |
196 | */ | |
90e535ef | 197 | LTTNG_HIDDEN |
0d37f2bc DG |
198 | ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len) |
199 | { | |
200 | struct msghdr msg; | |
201 | struct iovec iov[1]; | |
202 | ssize_t ret = -1; | |
203 | ||
204 | memset(&msg, 0, sizeof(msg)); | |
205 | ||
206 | iov[0].iov_base = buf; | |
207 | iov[0].iov_len = len; | |
208 | msg.msg_iov = iov; | |
209 | msg.msg_iovlen = 1; | |
210 | ||
211 | ret = sendmsg(sock, &msg, 0); | |
212 | if (ret < 0) { | |
213 | /* | |
214 | * Only warn about EPIPE when quiet mode is deactivated. | |
215 | * We consider EPIPE as expected. | |
216 | */ | |
217 | if (errno != EPIPE || !lttng_opt_quiet) { | |
218 | PERROR("sendmsg"); | |
219 | } | |
220 | } | |
221 | ||
222 | return ret; | |
223 | } | |
224 | ||
225 | /* | |
226 | * Shutdown cleanly a unix socket. | |
227 | */ | |
90e535ef | 228 | LTTNG_HIDDEN |
0d37f2bc DG |
229 | int lttcomm_close_unix_sock(int sock) |
230 | { | |
231 | int ret, closeret; | |
232 | ||
233 | /* Shutdown receptions and transmissions */ | |
234 | ret = shutdown(sock, SHUT_RDWR); | |
235 | if (ret < 0) { | |
236 | PERROR("shutdown"); | |
237 | } | |
238 | ||
239 | closeret = close(sock); | |
240 | if (closeret) { | |
241 | PERROR("close"); | |
242 | } | |
243 | ||
244 | return ret; | |
245 | } | |
246 | ||
247 | /* | |
248 | * Send a message accompanied by fd(s) over a unix socket. | |
249 | * | |
250 | * Returns the size of data sent, or negative error value. | |
251 | */ | |
90e535ef | 252 | LTTNG_HIDDEN |
0d37f2bc DG |
253 | ssize_t lttcomm_send_fds_unix_sock(int sock, int *fds, size_t nb_fd) |
254 | { | |
255 | struct msghdr msg; | |
256 | struct cmsghdr *cmptr; | |
257 | struct iovec iov[1]; | |
258 | ssize_t ret = -1; | |
259 | unsigned int sizeof_fds = nb_fd * sizeof(int); | |
260 | char tmp[CMSG_SPACE(sizeof_fds)]; | |
261 | char dummy = 0; | |
262 | ||
263 | memset(&msg, 0, sizeof(msg)); | |
c617c0c6 | 264 | memset(tmp, 0, CMSG_SPACE(sizeof_fds) * sizeof(char)); |
0d37f2bc DG |
265 | |
266 | if (nb_fd > LTTCOMM_MAX_SEND_FDS) | |
267 | return -EINVAL; | |
268 | ||
269 | msg.msg_control = (caddr_t)tmp; | |
270 | msg.msg_controllen = CMSG_LEN(sizeof_fds); | |
271 | ||
272 | cmptr = CMSG_FIRSTHDR(&msg); | |
273 | cmptr->cmsg_level = SOL_SOCKET; | |
274 | cmptr->cmsg_type = SCM_RIGHTS; | |
275 | cmptr->cmsg_len = CMSG_LEN(sizeof_fds); | |
276 | memcpy(CMSG_DATA(cmptr), fds, sizeof_fds); | |
277 | /* Sum of the length of all control messages in the buffer: */ | |
278 | msg.msg_controllen = cmptr->cmsg_len; | |
279 | ||
280 | iov[0].iov_base = &dummy; | |
281 | iov[0].iov_len = 1; | |
282 | msg.msg_iov = iov; | |
283 | msg.msg_iovlen = 1; | |
284 | ||
285 | do { | |
286 | ret = sendmsg(sock, &msg, 0); | |
287 | } while (ret < 0 && errno == EINTR); | |
288 | if (ret < 0) { | |
289 | /* | |
290 | * Only warn about EPIPE when quiet mode is deactivated. | |
291 | * We consider EPIPE as expected. | |
292 | */ | |
293 | if (errno != EPIPE || !lttng_opt_quiet) { | |
294 | PERROR("sendmsg"); | |
295 | } | |
296 | } | |
297 | return ret; | |
298 | } | |
299 | ||
300 | /* | |
301 | * Recv a message accompanied by fd(s) from a unix socket. | |
302 | * | |
303 | * Returns the size of received data, or negative error value. | |
304 | * | |
305 | * Expect at most "nb_fd" file descriptors. Returns the number of fd | |
306 | * actually received in nb_fd. | |
307 | */ | |
90e535ef | 308 | LTTNG_HIDDEN |
0d37f2bc DG |
309 | ssize_t lttcomm_recv_fds_unix_sock(int sock, int *fds, size_t nb_fd) |
310 | { | |
311 | struct iovec iov[1]; | |
312 | ssize_t ret = 0; | |
313 | struct cmsghdr *cmsg; | |
314 | size_t sizeof_fds = nb_fd * sizeof(int); | |
315 | char recv_fd[CMSG_SPACE(sizeof_fds)]; | |
316 | struct msghdr msg; | |
317 | char dummy; | |
318 | ||
319 | memset(&msg, 0, sizeof(msg)); | |
320 | ||
321 | /* Prepare to receive the structures */ | |
322 | iov[0].iov_base = &dummy; | |
323 | iov[0].iov_len = 1; | |
324 | msg.msg_iov = iov; | |
325 | msg.msg_iovlen = 1; | |
326 | msg.msg_control = recv_fd; | |
327 | msg.msg_controllen = sizeof(recv_fd); | |
328 | ||
329 | do { | |
330 | ret = recvmsg(sock, &msg, 0); | |
331 | } while (ret < 0 && errno == EINTR); | |
332 | if (ret < 0) { | |
333 | PERROR("recvmsg fds"); | |
334 | goto end; | |
335 | } | |
336 | if (ret != 1) { | |
337 | fprintf(stderr, "Error: Received %zd bytes, expected %d\n", | |
338 | ret, 1); | |
339 | goto end; | |
340 | } | |
341 | if (msg.msg_flags & MSG_CTRUNC) { | |
342 | fprintf(stderr, "Error: Control message truncated.\n"); | |
343 | ret = -1; | |
344 | goto end; | |
345 | } | |
346 | cmsg = CMSG_FIRSTHDR(&msg); | |
347 | if (!cmsg) { | |
348 | fprintf(stderr, "Error: Invalid control message header\n"); | |
349 | ret = -1; | |
350 | goto end; | |
351 | } | |
352 | if (cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS) { | |
353 | fprintf(stderr, "Didn't received any fd\n"); | |
354 | ret = -1; | |
355 | goto end; | |
356 | } | |
357 | if (cmsg->cmsg_len != CMSG_LEN(sizeof_fds)) { | |
358 | fprintf(stderr, "Error: Received %zu bytes of ancillary data, expected %zu\n", | |
359 | (size_t) cmsg->cmsg_len, (size_t) CMSG_LEN(sizeof_fds)); | |
360 | ret = -1; | |
361 | goto end; | |
362 | } | |
363 | memcpy(fds, CMSG_DATA(cmsg), sizeof_fds); | |
364 | ret = sizeof_fds; | |
365 | end: | |
366 | return ret; | |
367 | } | |
368 | ||
369 | /* | |
370 | * Send a message with credentials over a unix socket. | |
371 | * | |
372 | * Returns the size of data sent, or negative error value. | |
373 | */ | |
90e535ef | 374 | LTTNG_HIDDEN |
0d37f2bc DG |
375 | ssize_t lttcomm_send_creds_unix_sock(int sock, void *buf, size_t len) |
376 | { | |
377 | struct msghdr msg; | |
378 | struct iovec iov[1]; | |
379 | ssize_t ret = -1; | |
380 | #ifdef __linux__ | |
381 | struct cmsghdr *cmptr; | |
382 | size_t sizeof_cred = sizeof(lttng_sock_cred); | |
383 | char anc_buf[CMSG_SPACE(sizeof_cred)]; | |
384 | lttng_sock_cred *creds; | |
385 | #endif /* __linux__ */ | |
386 | ||
387 | memset(&msg, 0, sizeof(msg)); | |
c617c0c6 | 388 | memset(anc_buf, 0, CMSG_SPACE(sizeof_cred) * sizeof(char)); |
0d37f2bc DG |
389 | |
390 | iov[0].iov_base = buf; | |
391 | iov[0].iov_len = len; | |
392 | msg.msg_iov = iov; | |
393 | msg.msg_iovlen = 1; | |
394 | ||
395 | #ifdef __linux__ | |
396 | msg.msg_control = (caddr_t) anc_buf; | |
397 | msg.msg_controllen = CMSG_LEN(sizeof_cred); | |
398 | ||
399 | cmptr = CMSG_FIRSTHDR(&msg); | |
400 | cmptr->cmsg_level = SOL_SOCKET; | |
401 | cmptr->cmsg_type = LTTNG_SOCK_CREDS; | |
402 | cmptr->cmsg_len = CMSG_LEN(sizeof_cred); | |
403 | ||
404 | creds = (lttng_sock_cred*) CMSG_DATA(cmptr); | |
405 | ||
406 | LTTNG_SOCK_SET_UID_CRED(creds, geteuid()); | |
407 | LTTNG_SOCK_SET_GID_CRED(creds, getegid()); | |
408 | LTTNG_SOCK_SET_PID_CRED(creds, getpid()); | |
409 | #endif /* __linux__ */ | |
410 | ||
411 | do { | |
412 | ret = sendmsg(sock, &msg, 0); | |
413 | } while (ret < 0 && errno == EINTR); | |
414 | if (ret < 0) { | |
415 | /* | |
416 | * Only warn about EPIPE when quiet mode is deactivated. | |
417 | * We consider EPIPE as expected. | |
418 | */ | |
419 | if (errno != EPIPE || !lttng_opt_quiet) { | |
420 | PERROR("sendmsg"); | |
421 | } | |
422 | } | |
423 | return ret; | |
424 | } | |
425 | ||
426 | /* | |
427 | * Recv a message accompanied with credentials from a unix socket. | |
428 | * | |
429 | * Returns the size of received data, or negative error value. | |
430 | */ | |
90e535ef | 431 | LTTNG_HIDDEN |
0d37f2bc DG |
432 | ssize_t lttcomm_recv_creds_unix_sock(int sock, void *buf, size_t len, |
433 | lttng_sock_cred *creds) | |
434 | { | |
435 | struct msghdr msg; | |
436 | struct iovec iov[1]; | |
437 | ssize_t ret; | |
4100e49a | 438 | size_t len_last; |
0d37f2bc DG |
439 | #ifdef __linux__ |
440 | struct cmsghdr *cmptr; | |
441 | size_t sizeof_cred = sizeof(lttng_sock_cred); | |
442 | char anc_buf[CMSG_SPACE(sizeof_cred)]; | |
443 | #endif /* __linux__ */ | |
444 | ||
445 | memset(&msg, 0, sizeof(msg)); | |
446 | ||
447 | /* Not allowed */ | |
448 | if (creds == NULL) { | |
449 | ret = -1; | |
450 | goto end; | |
451 | } | |
452 | ||
453 | /* Prepare to receive the structures */ | |
454 | iov[0].iov_base = buf; | |
455 | iov[0].iov_len = len; | |
456 | msg.msg_iov = iov; | |
457 | msg.msg_iovlen = 1; | |
458 | ||
459 | #ifdef __linux__ | |
460 | msg.msg_control = anc_buf; | |
461 | msg.msg_controllen = sizeof(anc_buf); | |
462 | #endif /* __linux__ */ | |
463 | ||
464 | do { | |
4100e49a | 465 | len_last = iov[0].iov_len; |
0d37f2bc | 466 | ret = recvmsg(sock, &msg, 0); |
4100e49a DG |
467 | if (ret > 0) { |
468 | iov[0].iov_base += ret; | |
469 | iov[0].iov_len -= ret; | |
470 | assert(ret <= len_last); | |
471 | } | |
472 | } while ((ret > 0 && ret < len_last) || (ret < 0 && errno == EINTR)); | |
0d37f2bc DG |
473 | if (ret < 0) { |
474 | PERROR("recvmsg fds"); | |
475 | goto end; | |
4100e49a DG |
476 | } else if (ret > 0) { |
477 | ret = len; | |
0d37f2bc | 478 | } |
4100e49a | 479 | /* Else ret = 0 meaning an orderly shutdown. */ |
0d37f2bc DG |
480 | |
481 | #ifdef __linux__ | |
482 | if (msg.msg_flags & MSG_CTRUNC) { | |
483 | fprintf(stderr, "Error: Control message truncated.\n"); | |
484 | ret = -1; | |
485 | goto end; | |
486 | } | |
487 | ||
488 | cmptr = CMSG_FIRSTHDR(&msg); | |
489 | if (cmptr == NULL) { | |
490 | fprintf(stderr, "Error: Invalid control message header\n"); | |
491 | ret = -1; | |
492 | goto end; | |
493 | } | |
494 | ||
495 | if (cmptr->cmsg_level != SOL_SOCKET || | |
496 | cmptr->cmsg_type != LTTNG_SOCK_CREDS) { | |
497 | fprintf(stderr, "Didn't received any credentials\n"); | |
498 | ret = -1; | |
499 | goto end; | |
500 | } | |
501 | ||
502 | if (cmptr->cmsg_len != CMSG_LEN(sizeof_cred)) { | |
503 | fprintf(stderr, "Error: Received %zu bytes of ancillary data, expected %zu\n", | |
504 | (size_t) cmptr->cmsg_len, (size_t) CMSG_LEN(sizeof_cred)); | |
505 | ret = -1; | |
506 | goto end; | |
507 | } | |
508 | ||
509 | memcpy(creds, CMSG_DATA(cmptr), sizeof_cred); | |
510 | #elif (defined(__FreeBSD__) || defined(__CYGWIN__)) | |
511 | { | |
512 | int peer_ret; | |
513 | ||
514 | peer_ret = getpeereid(sock, &creds->uid, &creds->gid); | |
515 | if (peer_ret != 0) { | |
516 | return peer_ret; | |
517 | } | |
518 | } | |
519 | #else | |
520 | #error "Please implement credential support for your OS." | |
521 | #endif /* __linux__ */ | |
522 | ||
523 | end: | |
524 | return ret; | |
525 | } | |
526 | ||
527 | /* | |
528 | * Set socket option to use credentials passing. | |
529 | */ | |
530 | #ifdef __linux__ | |
90e535ef | 531 | LTTNG_HIDDEN |
0d37f2bc DG |
532 | int lttcomm_setsockopt_creds_unix_sock(int sock) |
533 | { | |
534 | int ret, on = 1; | |
535 | ||
536 | /* Set socket for credentials retrieval */ | |
537 | ret = setsockopt(sock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on)); | |
538 | if (ret < 0) { | |
539 | PERROR("setsockopt creds unix sock"); | |
540 | } | |
541 | return ret; | |
542 | } | |
543 | #elif (defined(__FreeBSD__) || defined(__CYGWIN__)) | |
90e535ef | 544 | LTTNG_HIDDEN |
0d37f2bc DG |
545 | int lttcomm_setsockopt_creds_unix_sock(int sock) |
546 | { | |
547 | return 0; | |
548 | } | |
549 | #else | |
550 | #error "Please implement credential support for your OS." | |
551 | #endif /* __linux__ */ |