]>
Commit | Line | Data |
---|---|---|
663996b3 MS |
1 | /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ |
2 | ||
3 | /*** | |
4 | This file is part of systemd. | |
5 | ||
6 | Copyright 2011 Lennart Poettering | |
7 | ||
8 | systemd is free software; you can redistribute it and/or modify it | |
9 | under the terms of the GNU Lesser General Public License as published by | |
10 | the Free Software Foundation; either version 2.1 of the License, or | |
11 | (at your option) any later version. | |
12 | ||
13 | systemd is distributed in the hope that it will be useful, but | |
14 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
16 | Lesser General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU Lesser General Public License | |
19 | along with systemd; If not, see <http://www.gnu.org/licenses/>. | |
20 | ***/ | |
21 | ||
22 | #include <unistd.h> | |
23 | #include <stddef.h> | |
24 | #include <sys/epoll.h> | |
f47781d8 | 25 | #include <sys/mman.h> |
663996b3 MS |
26 | |
27 | #include "socket-util.h" | |
28 | #include "path-util.h" | |
60f067b4 | 29 | #include "selinux-util.h" |
663996b3 MS |
30 | #include "journald-server.h" |
31 | #include "journald-native.h" | |
32 | #include "journald-kmsg.h" | |
33 | #include "journald-console.h" | |
34 | #include "journald-syslog.h" | |
60f067b4 | 35 | #include "journald-wall.h" |
f47781d8 | 36 | #include "memfd-util.h" |
663996b3 | 37 | |
60f067b4 | 38 | bool valid_user_field(const char *p, size_t l, bool allow_protected) { |
663996b3 MS |
39 | const char *a; |
40 | ||
41 | /* We kinda enforce POSIX syntax recommendations for | |
42 | environment variables here, but make a couple of additional | |
43 | requirements. | |
44 | ||
45 | http://pubs.opengroup.org/onlinepubs/000095399/basedefs/xbd_chap08.html */ | |
46 | ||
47 | /* No empty field names */ | |
48 | if (l <= 0) | |
49 | return false; | |
50 | ||
51 | /* Don't allow names longer than 64 chars */ | |
52 | if (l > 64) | |
53 | return false; | |
54 | ||
55 | /* Variables starting with an underscore are protected */ | |
60f067b4 | 56 | if (!allow_protected && p[0] == '_') |
663996b3 MS |
57 | return false; |
58 | ||
59 | /* Don't allow digits as first character */ | |
60 | if (p[0] >= '0' && p[0] <= '9') | |
61 | return false; | |
62 | ||
63 | /* Only allow A-Z0-9 and '_' */ | |
64 | for (a = p; a < p + l; a++) | |
60f067b4 JS |
65 | if ((*a < 'A' || *a > 'Z') && |
66 | (*a < '0' || *a > '9') && | |
67 | *a != '_') | |
663996b3 MS |
68 | return false; |
69 | ||
70 | return true; | |
71 | } | |
72 | ||
f47781d8 | 73 | static bool allow_object_pid(const struct ucred *ucred) { |
14228c0d MB |
74 | return ucred && ucred->uid == 0; |
75 | } | |
76 | ||
663996b3 MS |
77 | void server_process_native_message( |
78 | Server *s, | |
79 | const void *buffer, size_t buffer_size, | |
f47781d8 MP |
80 | const struct ucred *ucred, |
81 | const struct timeval *tv, | |
663996b3 MS |
82 | const char *label, size_t label_len) { |
83 | ||
84 | struct iovec *iovec = NULL; | |
14228c0d | 85 | unsigned n = 0, j, tn = (unsigned) -1; |
663996b3 | 86 | const char *p; |
5eef597e | 87 | size_t remaining, m = 0, entry_size = 0; |
663996b3 MS |
88 | int priority = LOG_INFO; |
89 | char *identifier = NULL, *message = NULL; | |
14228c0d | 90 | pid_t object_pid = 0; |
663996b3 MS |
91 | |
92 | assert(s); | |
93 | assert(buffer || buffer_size == 0); | |
94 | ||
95 | p = buffer; | |
96 | remaining = buffer_size; | |
97 | ||
98 | while (remaining > 0) { | |
99 | const char *e, *q; | |
100 | ||
101 | e = memchr(p, '\n', remaining); | |
102 | ||
103 | if (!e) { | |
104 | /* Trailing noise, let's ignore it, and flush what we collected */ | |
105 | log_debug("Received message with trailing noise, ignoring."); | |
106 | break; | |
107 | } | |
108 | ||
109 | if (e == p) { | |
110 | /* Entry separator */ | |
5eef597e MP |
111 | |
112 | if (entry_size + n + 1 > ENTRY_SIZE_MAX) { /* data + separators + trailer */ | |
113 | log_debug("Entry is too big with %u properties and %zu bytes, ignoring.", n, entry_size); | |
114 | continue; | |
115 | } | |
116 | ||
14228c0d | 117 | server_dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority, object_pid); |
663996b3 MS |
118 | n = 0; |
119 | priority = LOG_INFO; | |
5eef597e | 120 | entry_size = 0; |
663996b3 MS |
121 | |
122 | p++; | |
123 | remaining--; | |
124 | continue; | |
125 | } | |
126 | ||
127 | if (*p == '.' || *p == '#') { | |
128 | /* Ignore control commands for now, and | |
129 | * comments too. */ | |
130 | remaining -= (e - p) + 1; | |
131 | p = e + 1; | |
132 | continue; | |
133 | } | |
134 | ||
135 | /* A property follows */ | |
136 | ||
e735f4d4 MP |
137 | /* n existing properties, 1 new, +1 for _TRANSPORT */ |
138 | if (!GREEDY_REALLOC(iovec, m, n + 2 + N_IOVEC_META_FIELDS + N_IOVEC_OBJECT_FIELDS)) { | |
14228c0d MB |
139 | log_oom(); |
140 | break; | |
663996b3 MS |
141 | } |
142 | ||
143 | q = memchr(p, '=', e - p); | |
144 | if (q) { | |
60f067b4 | 145 | if (valid_user_field(p, q - p, false)) { |
663996b3 MS |
146 | size_t l; |
147 | ||
148 | l = e - p; | |
149 | ||
150 | /* If the field name starts with an | |
151 | * underscore, skip the variable, | |
152 | * since that indidates a trusted | |
153 | * field */ | |
154 | iovec[n].iov_base = (char*) p; | |
155 | iovec[n].iov_len = l; | |
5eef597e | 156 | entry_size += iovec[n].iov_len; |
663996b3 MS |
157 | n++; |
158 | ||
159 | /* We need to determine the priority | |
160 | * of this entry for the rate limiting | |
161 | * logic */ | |
162 | if (l == 10 && | |
14228c0d | 163 | startswith(p, "PRIORITY=") && |
663996b3 MS |
164 | p[9] >= '0' && p[9] <= '9') |
165 | priority = (priority & LOG_FACMASK) | (p[9] - '0'); | |
166 | ||
167 | else if (l == 17 && | |
14228c0d | 168 | startswith(p, "SYSLOG_FACILITY=") && |
663996b3 MS |
169 | p[16] >= '0' && p[16] <= '9') |
170 | priority = (priority & LOG_PRIMASK) | ((p[16] - '0') << 3); | |
171 | ||
172 | else if (l == 18 && | |
14228c0d | 173 | startswith(p, "SYSLOG_FACILITY=") && |
663996b3 MS |
174 | p[16] >= '0' && p[16] <= '9' && |
175 | p[17] >= '0' && p[17] <= '9') | |
176 | priority = (priority & LOG_PRIMASK) | (((p[16] - '0')*10 + (p[17] - '0')) << 3); | |
177 | ||
178 | else if (l >= 19 && | |
14228c0d | 179 | startswith(p, "SYSLOG_IDENTIFIER=")) { |
663996b3 MS |
180 | char *t; |
181 | ||
182 | t = strndup(p + 18, l - 18); | |
183 | if (t) { | |
184 | free(identifier); | |
185 | identifier = t; | |
186 | } | |
187 | } else if (l >= 8 && | |
14228c0d | 188 | startswith(p, "MESSAGE=")) { |
663996b3 MS |
189 | char *t; |
190 | ||
191 | t = strndup(p + 8, l - 8); | |
192 | if (t) { | |
193 | free(message); | |
194 | message = t; | |
195 | } | |
14228c0d MB |
196 | } else if (l > strlen("OBJECT_PID=") && |
197 | l < strlen("OBJECT_PID=") + DECIMAL_STR_MAX(pid_t) && | |
198 | startswith(p, "OBJECT_PID=") && | |
199 | allow_object_pid(ucred)) { | |
200 | char buf[DECIMAL_STR_MAX(pid_t)]; | |
201 | memcpy(buf, p + strlen("OBJECT_PID="), l - strlen("OBJECT_PID=")); | |
202 | char_array_0(buf); | |
203 | ||
204 | /* ignore error */ | |
205 | parse_pid(buf, &object_pid); | |
663996b3 MS |
206 | } |
207 | } | |
208 | ||
209 | remaining -= (e - p) + 1; | |
210 | p = e + 1; | |
211 | continue; | |
212 | } else { | |
213 | le64_t l_le; | |
214 | uint64_t l; | |
215 | char *k; | |
216 | ||
217 | if (remaining < e - p + 1 + sizeof(uint64_t) + 1) { | |
218 | log_debug("Failed to parse message, ignoring."); | |
219 | break; | |
220 | } | |
221 | ||
222 | memcpy(&l_le, e + 1, sizeof(uint64_t)); | |
223 | l = le64toh(l_le); | |
224 | ||
225 | if (l > DATA_SIZE_MAX) { | |
5eef597e | 226 | log_debug("Received binary data block of %"PRIu64" bytes is too large, ignoring.", l); |
663996b3 MS |
227 | break; |
228 | } | |
229 | ||
230 | if ((uint64_t) remaining < e - p + 1 + sizeof(uint64_t) + l + 1 || | |
231 | e[1+sizeof(uint64_t)+l] != '\n') { | |
232 | log_debug("Failed to parse message, ignoring."); | |
233 | break; | |
234 | } | |
235 | ||
236 | k = malloc((e - p) + 1 + l); | |
237 | if (!k) { | |
238 | log_oom(); | |
239 | break; | |
240 | } | |
241 | ||
242 | memcpy(k, p, e - p); | |
243 | k[e - p] = '='; | |
244 | memcpy(k + (e - p) + 1, e + 1 + sizeof(uint64_t), l); | |
245 | ||
60f067b4 | 246 | if (valid_user_field(p, e - p, false)) { |
663996b3 MS |
247 | iovec[n].iov_base = k; |
248 | iovec[n].iov_len = (e - p) + 1 + l; | |
5eef597e | 249 | entry_size += iovec[n].iov_len; |
663996b3 MS |
250 | n++; |
251 | } else | |
252 | free(k); | |
253 | ||
254 | remaining -= (e - p) + 1 + sizeof(uint64_t) + l + 1; | |
255 | p = e + 1 + sizeof(uint64_t) + l + 1; | |
256 | } | |
257 | } | |
258 | ||
259 | if (n <= 0) | |
260 | goto finish; | |
261 | ||
262 | tn = n++; | |
263 | IOVEC_SET_STRING(iovec[tn], "_TRANSPORT=journal"); | |
5eef597e MP |
264 | entry_size += strlen("_TRANSPORT=journal"); |
265 | ||
266 | if (entry_size + n + 1 > ENTRY_SIZE_MAX) { /* data + separators + trailer */ | |
267 | log_debug("Entry is too big with %u properties and %zu bytes, ignoring.", | |
268 | n, entry_size); | |
269 | goto finish; | |
270 | } | |
663996b3 MS |
271 | |
272 | if (message) { | |
273 | if (s->forward_to_syslog) | |
274 | server_forward_syslog(s, priority, identifier, message, ucred, tv); | |
275 | ||
276 | if (s->forward_to_kmsg) | |
277 | server_forward_kmsg(s, priority, identifier, message, ucred); | |
278 | ||
279 | if (s->forward_to_console) | |
280 | server_forward_console(s, priority, identifier, message, ucred); | |
60f067b4 JS |
281 | |
282 | if (s->forward_to_wall) | |
283 | server_forward_wall(s, priority, identifier, message, ucred); | |
663996b3 MS |
284 | } |
285 | ||
14228c0d | 286 | server_dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority, object_pid); |
663996b3 MS |
287 | |
288 | finish: | |
289 | for (j = 0; j < n; j++) { | |
290 | if (j == tn) | |
291 | continue; | |
292 | ||
293 | if (iovec[j].iov_base < buffer || | |
294 | (const uint8_t*) iovec[j].iov_base >= (const uint8_t*) buffer + buffer_size) | |
295 | free(iovec[j].iov_base); | |
296 | } | |
297 | ||
298 | free(iovec); | |
299 | free(identifier); | |
300 | free(message); | |
301 | } | |
302 | ||
303 | void server_process_native_file( | |
304 | Server *s, | |
305 | int fd, | |
f47781d8 MP |
306 | const struct ucred *ucred, |
307 | const struct timeval *tv, | |
663996b3 MS |
308 | const char *label, size_t label_len) { |
309 | ||
310 | struct stat st; | |
f47781d8 | 311 | bool sealed; |
663996b3 MS |
312 | int r; |
313 | ||
f47781d8 MP |
314 | /* Data is in the passed fd, since it didn't fit in a |
315 | * datagram. */ | |
316 | ||
663996b3 MS |
317 | assert(s); |
318 | assert(fd >= 0); | |
319 | ||
f47781d8 MP |
320 | /* If it's a memfd, check if it is sealed. If so, we can just |
321 | * use map it and use it, and do not need to copy the data | |
322 | * out. */ | |
323 | sealed = memfd_get_sealed(fd) > 0; | |
324 | ||
325 | if (!sealed && (!ucred || ucred->uid != 0)) { | |
663996b3 MS |
326 | _cleanup_free_ char *sl = NULL, *k = NULL; |
327 | const char *e; | |
328 | ||
f47781d8 MP |
329 | /* If this is not a sealed memfd, and the peer is unknown or |
330 | * unprivileged, then verify the path. */ | |
331 | ||
663996b3 MS |
332 | if (asprintf(&sl, "/proc/self/fd/%i", fd) < 0) { |
333 | log_oom(); | |
334 | return; | |
335 | } | |
336 | ||
337 | r = readlink_malloc(sl, &k); | |
338 | if (r < 0) { | |
f47781d8 | 339 | log_error_errno(errno, "readlink(%s) failed: %m", sl); |
663996b3 MS |
340 | return; |
341 | } | |
342 | ||
343 | e = path_startswith(k, "/dev/shm/"); | |
344 | if (!e) | |
345 | e = path_startswith(k, "/tmp/"); | |
346 | if (!e) | |
347 | e = path_startswith(k, "/var/tmp/"); | |
348 | if (!e) { | |
349 | log_error("Received file outside of allowed directories. Refusing."); | |
350 | return; | |
351 | } | |
352 | ||
e735f4d4 | 353 | if (!filename_is_valid(e)) { |
663996b3 MS |
354 | log_error("Received file in subdirectory of allowed directories. Refusing."); |
355 | return; | |
356 | } | |
357 | } | |
358 | ||
663996b3 | 359 | if (fstat(fd, &st) < 0) { |
f47781d8 | 360 | log_error_errno(errno, "Failed to stat passed file, ignoring: %m"); |
663996b3 MS |
361 | return; |
362 | } | |
363 | ||
364 | if (!S_ISREG(st.st_mode)) { | |
365 | log_error("File passed is not regular. Ignoring."); | |
366 | return; | |
367 | } | |
368 | ||
369 | if (st.st_size <= 0) | |
370 | return; | |
371 | ||
372 | if (st.st_size > ENTRY_SIZE_MAX) { | |
373 | log_error("File passed too large. Ignoring."); | |
374 | return; | |
375 | } | |
376 | ||
f47781d8 MP |
377 | if (sealed) { |
378 | void *p; | |
379 | size_t ps; | |
380 | ||
381 | /* The file is sealed, we can just map it and use it. */ | |
663996b3 | 382 | |
f47781d8 MP |
383 | ps = PAGE_ALIGN(st.st_size); |
384 | p = mmap(NULL, ps, PROT_READ, MAP_PRIVATE, fd, 0); | |
385 | if (p == MAP_FAILED) { | |
386 | log_error_errno(errno, "Failed to map memfd, ignoring: %m"); | |
387 | return; | |
388 | } | |
389 | ||
390 | server_process_native_message(s, p, st.st_size, ucred, tv, label, label_len); | |
391 | assert_se(munmap(p, ps) >= 0); | |
392 | } else { | |
393 | _cleanup_free_ void *p = NULL; | |
394 | ssize_t n; | |
395 | ||
396 | /* The file is not sealed, we can't map the file here, since | |
397 | * clients might then truncate it and trigger a SIGBUS for | |
398 | * us. So let's stupidly read it */ | |
399 | ||
400 | p = malloc(st.st_size); | |
401 | if (!p) { | |
402 | log_oom(); | |
403 | return; | |
404 | } | |
405 | ||
406 | n = pread(fd, p, st.st_size, 0); | |
407 | if (n < 0) | |
408 | log_error_errno(n, "Failed to read file, ignoring: %m"); | |
409 | else if (n > 0) | |
410 | server_process_native_message(s, p, n, ucred, tv, label, label_len); | |
411 | } | |
663996b3 MS |
412 | } |
413 | ||
414 | int server_open_native_socket(Server*s) { | |
f47781d8 MP |
415 | static const int one = 1; |
416 | int r; | |
663996b3 MS |
417 | |
418 | assert(s); | |
419 | ||
420 | if (s->native_fd < 0) { | |
5eef597e MP |
421 | union sockaddr_union sa = { |
422 | .un.sun_family = AF_UNIX, | |
423 | .un.sun_path = "/run/systemd/journal/socket", | |
424 | }; | |
663996b3 MS |
425 | |
426 | s->native_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); | |
f47781d8 MP |
427 | if (s->native_fd < 0) |
428 | return log_error_errno(errno, "socket() failed: %m"); | |
663996b3 | 429 | |
663996b3 MS |
430 | unlink(sa.un.sun_path); |
431 | ||
432 | r = bind(s->native_fd, &sa.sa, offsetof(union sockaddr_union, un.sun_path) + strlen(sa.un.sun_path)); | |
f47781d8 MP |
433 | if (r < 0) |
434 | return log_error_errno(errno, "bind(%s) failed: %m", sa.un.sun_path); | |
663996b3 | 435 | |
e3bff60a | 436 | (void) chmod(sa.un.sun_path, 0666); |
663996b3 MS |
437 | } else |
438 | fd_nonblock(s->native_fd, 1); | |
439 | ||
663996b3 | 440 | r = setsockopt(s->native_fd, SOL_SOCKET, SO_PASSCRED, &one, sizeof(one)); |
f47781d8 MP |
441 | if (r < 0) |
442 | return log_error_errno(errno, "SO_PASSCRED failed: %m"); | |
663996b3 MS |
443 | |
444 | #ifdef HAVE_SELINUX | |
5eef597e | 445 | if (mac_selinux_use()) { |
60f067b4 JS |
446 | r = setsockopt(s->native_fd, SOL_SOCKET, SO_PASSSEC, &one, sizeof(one)); |
447 | if (r < 0) | |
f47781d8 | 448 | log_warning_errno(errno, "SO_PASSSEC failed: %m"); |
60f067b4 | 449 | } |
663996b3 MS |
450 | #endif |
451 | ||
663996b3 | 452 | r = setsockopt(s->native_fd, SOL_SOCKET, SO_TIMESTAMP, &one, sizeof(one)); |
f47781d8 MP |
453 | if (r < 0) |
454 | return log_error_errno(errno, "SO_TIMESTAMP failed: %m"); | |
663996b3 | 455 | |
e735f4d4 | 456 | r = sd_event_add_io(s->event, &s->native_event_source, s->native_fd, EPOLLIN, server_process_datagram, s); |
f47781d8 MP |
457 | if (r < 0) |
458 | return log_error_errno(r, "Failed to add native server fd to event loop: %m"); | |
663996b3 MS |
459 | |
460 | return 0; | |
461 | } |