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53e1b683 | 1 | /* SPDX-License-Identifier: LGPL-2.1+ */ |
22e3a02b LP |
2 | /*** |
3 | This file is part of systemd. | |
4 | ||
5 | Copyright 2017 Lennart Poettering | |
6 | ||
7 | systemd is free software; you can redistribute it and/or modify it | |
8 | under the terms of the GNU Lesser General Public License as published by | |
9 | the Free Software Foundation; either version 2.1 of the License, or | |
10 | (at your option) any later version. | |
11 | ||
12 | systemd is distributed in the hope that it will be useful, but | |
13 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | Lesser General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU Lesser General Public License | |
18 | along with systemd; If not, see <http://www.gnu.org/licenses/>. | |
19 | ***/ | |
20 | ||
349cc4a5 | 21 | #if HAVE_SELINUX |
22e3a02b LP |
22 | #include <selinux/selinux.h> |
23 | #endif | |
24 | ||
25 | #include "alloc-util.h" | |
26 | #include "audit-util.h" | |
27 | #include "cgroup-util.h" | |
d3070fbd LP |
28 | #include "fd-util.h" |
29 | #include "fileio.h" | |
30 | #include "fs-util.h" | |
31 | #include "io-util.h" | |
32 | #include "journal-util.h" | |
22e3a02b LP |
33 | #include "journald-context.h" |
34 | #include "process-util.h" | |
35 | #include "string-util.h" | |
d3070fbd LP |
36 | #include "syslog-util.h" |
37 | #include "unaligned.h" | |
22e3a02b LP |
38 | #include "user-util.h" |
39 | ||
40 | /* This implements a metadata cache for clients, which are identified by their PID. Requesting metadata through /proc | |
41 | * is expensive, hence let's cache the data if we can. Note that this means the metadata might be out-of-date when we | |
42 | * store it, but it might already be anyway, as we request the data asynchronously from /proc at a different time the | |
43 | * log entry was originally created. We hence just increase the "window of inaccuracy" a bit. | |
44 | * | |
45 | * The cache is indexed by the PID. Entries may be "pinned" in the cache, in which case the entries are not removed | |
46 | * until they are unpinned. Unpinned entries are kept around until cache pressure is seen. Cache entries older than 5s | |
47 | * are never used (a sad attempt to deal with the UNIX weakness of PIDs reuse), cache entries older than 1s are | |
48 | * refreshed in an incremental way (meaning: data is reread from /proc, but any old data we can't refresh is not | |
49 | * flushed out). Data newer than 1s is used immediately without refresh. | |
50 | * | |
51 | * Log stream clients (i.e. all clients using the AF_UNIX/SOCK_STREAM stdout/stderr transport) will pin a cache entry | |
52 | * as long as their socket is connected. Note that cache entries are shared between different transports. That means a | |
53 | * cache entry pinned for the stream connection logic may be reused for the syslog or native protocols. | |
54 | * | |
55 | * Caching metadata like this has two major benefits: | |
56 | * | |
57 | * 1. Reading metadata is expensive, and we can thus substantially speed up log processing under flood. | |
58 | * | |
59 | * 2. Because metadata caching is shared between stream and datagram transports and stream connections pin a cache | |
60 | * entry there's a good chance we can properly map a substantial set of datagram log messages to their originating | |
61 | * service, as all services (unless explicitly configured otherwise) will have their stdout/stderr connected to a | |
62 | * stream connection. This should improve cases where a service process logs immediately before exiting and we | |
63 | * previously had trouble associating the log message with the service. | |
64 | * | |
65 | * NB: With and without the metadata cache: the implicitly added entry metadata in the journal (with the exception of | |
66 | * UID/PID/GID and SELinux label) must be understood as possibly slightly out of sync (i.e. sometimes slighly older | |
67 | * and sometimes slightly newer than what was current at the log event). | |
68 | */ | |
69 | ||
70 | /* We refresh every 1s */ | |
71 | #define REFRESH_USEC (1*USEC_PER_SEC) | |
72 | ||
73 | /* Data older than 5s we flush out */ | |
74 | #define MAX_USEC (5*USEC_PER_SEC) | |
75 | ||
76 | /* Keep at most 16K entries in the cache. (Note though that this limit may be violated if enough streams pin entries in | |
77 | * the cache, in which case we *do* permit this limit to be breached. That's safe however, as the number of stream | |
78 | * clients itself is limited.) */ | |
79 | #define CACHE_MAX (16*1024) | |
80 | ||
81 | static int client_context_compare(const void *a, const void *b) { | |
82 | const ClientContext *x = a, *y = b; | |
83 | ||
84 | if (x->timestamp < y->timestamp) | |
85 | return -1; | |
86 | if (x->timestamp > y->timestamp) | |
87 | return 1; | |
88 | ||
89 | if (x->pid < y->pid) | |
90 | return -1; | |
91 | if (x->pid > y->pid) | |
92 | return 1; | |
93 | ||
94 | return 0; | |
95 | } | |
96 | ||
97 | static int client_context_new(Server *s, pid_t pid, ClientContext **ret) { | |
98 | ClientContext *c; | |
99 | int r; | |
100 | ||
101 | assert(s); | |
102 | assert(pid_is_valid(pid)); | |
103 | assert(ret); | |
104 | ||
105 | r = hashmap_ensure_allocated(&s->client_contexts, NULL); | |
106 | if (r < 0) | |
107 | return r; | |
108 | ||
109 | r = prioq_ensure_allocated(&s->client_contexts_lru, client_context_compare); | |
110 | if (r < 0) | |
111 | return r; | |
112 | ||
113 | c = new0(ClientContext, 1); | |
114 | if (!c) | |
115 | return -ENOMEM; | |
116 | ||
117 | c->pid = pid; | |
118 | ||
119 | c->uid = UID_INVALID; | |
120 | c->gid = GID_INVALID; | |
121 | c->auditid = AUDIT_SESSION_INVALID; | |
122 | c->loginuid = UID_INVALID; | |
123 | c->owner_uid = UID_INVALID; | |
124 | c->lru_index = PRIOQ_IDX_NULL; | |
125 | c->timestamp = USEC_INFINITY; | |
d3070fbd LP |
126 | c->extra_fields_mtime = NSEC_INFINITY; |
127 | c->log_level_max = -1; | |
22e3a02b LP |
128 | |
129 | r = hashmap_put(s->client_contexts, PID_TO_PTR(pid), c); | |
130 | if (r < 0) { | |
131 | free(c); | |
132 | return r; | |
133 | } | |
134 | ||
135 | *ret = c; | |
136 | return 0; | |
137 | } | |
138 | ||
139 | static void client_context_reset(ClientContext *c) { | |
140 | assert(c); | |
141 | ||
142 | c->timestamp = USEC_INFINITY; | |
143 | ||
144 | c->uid = UID_INVALID; | |
145 | c->gid = GID_INVALID; | |
146 | ||
147 | c->comm = mfree(c->comm); | |
148 | c->exe = mfree(c->exe); | |
149 | c->cmdline = mfree(c->cmdline); | |
150 | c->capeff = mfree(c->capeff); | |
151 | ||
152 | c->auditid = AUDIT_SESSION_INVALID; | |
153 | c->loginuid = UID_INVALID; | |
154 | ||
155 | c->cgroup = mfree(c->cgroup); | |
156 | c->session = mfree(c->session); | |
157 | c->owner_uid = UID_INVALID; | |
158 | c->unit = mfree(c->unit); | |
159 | c->user_unit = mfree(c->user_unit); | |
160 | c->slice = mfree(c->slice); | |
161 | c->user_slice = mfree(c->user_slice); | |
162 | ||
163 | c->invocation_id = SD_ID128_NULL; | |
164 | ||
165 | c->label = mfree(c->label); | |
166 | c->label_size = 0; | |
d3070fbd LP |
167 | |
168 | c->extra_fields_iovec = mfree(c->extra_fields_iovec); | |
169 | c->extra_fields_n_iovec = 0; | |
170 | c->extra_fields_data = mfree(c->extra_fields_data); | |
171 | c->extra_fields_mtime = NSEC_INFINITY; | |
172 | ||
173 | c->log_level_max = -1; | |
22e3a02b LP |
174 | } |
175 | ||
176 | static ClientContext* client_context_free(Server *s, ClientContext *c) { | |
177 | assert(s); | |
178 | ||
179 | if (!c) | |
180 | return NULL; | |
181 | ||
182 | assert_se(hashmap_remove(s->client_contexts, PID_TO_PTR(c->pid)) == c); | |
183 | ||
184 | if (c->in_lru) | |
185 | assert_se(prioq_remove(s->client_contexts_lru, c, &c->lru_index) >= 0); | |
186 | ||
187 | client_context_reset(c); | |
188 | ||
189 | return mfree(c); | |
190 | } | |
191 | ||
192 | static void client_context_read_uid_gid(ClientContext *c, const struct ucred *ucred) { | |
193 | assert(c); | |
194 | assert(pid_is_valid(c->pid)); | |
195 | ||
196 | /* The ucred data passed in is always the most current and accurate, if we have any. Use it. */ | |
197 | if (ucred && uid_is_valid(ucred->uid)) | |
198 | c->uid = ucred->uid; | |
199 | else | |
200 | (void) get_process_uid(c->pid, &c->uid); | |
201 | ||
202 | if (ucred && gid_is_valid(ucred->gid)) | |
203 | c->gid = ucred->gid; | |
204 | else | |
205 | (void) get_process_gid(c->pid, &c->gid); | |
206 | } | |
207 | ||
208 | static void client_context_read_basic(ClientContext *c) { | |
209 | char *t; | |
210 | ||
211 | assert(c); | |
212 | assert(pid_is_valid(c->pid)); | |
213 | ||
214 | if (get_process_comm(c->pid, &t) >= 0) | |
215 | free_and_replace(c->comm, t); | |
216 | ||
217 | if (get_process_exe(c->pid, &t) >= 0) | |
218 | free_and_replace(c->exe, t); | |
219 | ||
220 | if (get_process_cmdline(c->pid, 0, false, &t) >= 0) | |
221 | free_and_replace(c->cmdline, t); | |
222 | ||
223 | if (get_process_capeff(c->pid, &t) >= 0) | |
224 | free_and_replace(c->capeff, t); | |
225 | } | |
226 | ||
227 | static int client_context_read_label( | |
228 | ClientContext *c, | |
229 | const char *label, size_t label_size) { | |
230 | ||
231 | assert(c); | |
232 | assert(pid_is_valid(c->pid)); | |
233 | assert(label_size == 0 || label); | |
234 | ||
235 | if (label_size > 0) { | |
236 | char *l; | |
237 | ||
238 | /* If we got an SELinux label passed in it counts. */ | |
239 | ||
240 | l = newdup_suffix0(char, label, label_size); | |
241 | if (!l) | |
242 | return -ENOMEM; | |
243 | ||
244 | free_and_replace(c->label, l); | |
245 | c->label_size = label_size; | |
246 | } | |
349cc4a5 | 247 | #if HAVE_SELINUX |
22e3a02b LP |
248 | else { |
249 | char *con; | |
250 | ||
251 | /* If we got no SELinux label passed in, let's try to acquire one */ | |
252 | ||
253 | if (getpidcon(c->pid, &con) >= 0) { | |
254 | free_and_replace(c->label, con); | |
255 | c->label_size = strlen(c->label); | |
256 | } | |
257 | } | |
258 | #endif | |
259 | ||
260 | return 0; | |
261 | } | |
262 | ||
263 | static int client_context_read_cgroup(Server *s, ClientContext *c, const char *unit_id) { | |
264 | char *t = NULL; | |
265 | int r; | |
266 | ||
267 | assert(c); | |
268 | ||
269 | /* Try to acquire the current cgroup path */ | |
270 | r = cg_pid_get_path_shifted(c->pid, s->cgroup_root, &t); | |
271 | if (r < 0) { | |
272 | ||
273 | /* If that didn't work, we use the unit ID passed in as fallback, if we have nothing cached yet */ | |
274 | if (unit_id && !c->unit) { | |
275 | c->unit = strdup(unit_id); | |
276 | if (c->unit) | |
277 | return 0; | |
278 | } | |
279 | ||
280 | return r; | |
281 | } | |
282 | ||
283 | /* Let's shortcut this if the cgroup path didn't change */ | |
284 | if (streq_ptr(c->cgroup, t)) { | |
285 | free(t); | |
286 | return 0; | |
287 | } | |
288 | ||
289 | free_and_replace(c->cgroup, t); | |
290 | ||
291 | (void) cg_path_get_session(c->cgroup, &t); | |
292 | free_and_replace(c->session, t); | |
293 | ||
294 | if (cg_path_get_owner_uid(c->cgroup, &c->owner_uid) < 0) | |
295 | c->owner_uid = UID_INVALID; | |
296 | ||
297 | (void) cg_path_get_unit(c->cgroup, &t); | |
298 | free_and_replace(c->unit, t); | |
299 | ||
300 | (void) cg_path_get_user_unit(c->cgroup, &t); | |
301 | free_and_replace(c->user_unit, t); | |
302 | ||
303 | (void) cg_path_get_slice(c->cgroup, &t); | |
304 | free_and_replace(c->slice, t); | |
305 | ||
306 | (void) cg_path_get_user_slice(c->cgroup, &t); | |
307 | free_and_replace(c->user_slice, t); | |
308 | ||
309 | return 0; | |
310 | } | |
311 | ||
312 | static int client_context_read_invocation_id( | |
313 | Server *s, | |
314 | ClientContext *c) { | |
315 | ||
d3070fbd | 316 | _cleanup_free_ char *value = NULL; |
22e3a02b LP |
317 | const char *p; |
318 | int r; | |
319 | ||
320 | assert(s); | |
321 | assert(c); | |
322 | ||
d3070fbd | 323 | /* Read the invocation ID of a unit off a unit. PID 1 stores it in a per-unit symlink in /run/systemd/units/ */ |
22e3a02b | 324 | |
d3070fbd | 325 | if (!c->unit) |
22e3a02b LP |
326 | return 0; |
327 | ||
d3070fbd LP |
328 | p = strjoina("/run/systemd/units/invocation:", c->unit); |
329 | r = readlink_malloc(p, &value); | |
22e3a02b LP |
330 | if (r < 0) |
331 | return r; | |
332 | ||
d3070fbd LP |
333 | return sd_id128_from_string(value, &c->invocation_id); |
334 | } | |
22e3a02b | 335 | |
d3070fbd LP |
336 | static int client_context_read_log_level_max( |
337 | Server *s, | |
338 | ClientContext *c) { | |
22e3a02b | 339 | |
d3070fbd LP |
340 | _cleanup_free_ char *value = NULL; |
341 | const char *p; | |
342 | int r, ll; | |
343 | ||
344 | if (!c->unit) | |
345 | return 0; | |
346 | ||
347 | p = strjoina("/run/systemd/units/log-level-max:", c->unit); | |
348 | r = readlink_malloc(p, &value); | |
22e3a02b LP |
349 | if (r < 0) |
350 | return r; | |
d3070fbd LP |
351 | |
352 | ll = log_level_from_string(value); | |
353 | if (ll < 0) | |
22e3a02b | 354 | return -EINVAL; |
22e3a02b | 355 | |
d3070fbd LP |
356 | c->log_level_max = ll; |
357 | return 0; | |
358 | } | |
359 | ||
360 | static int client_context_read_extra_fields( | |
361 | Server *s, | |
362 | ClientContext *c) { | |
363 | ||
364 | size_t size = 0, n_iovec = 0, n_allocated = 0, left; | |
365 | _cleanup_free_ struct iovec *iovec = NULL; | |
366 | _cleanup_free_ void *data = NULL; | |
367 | _cleanup_fclose_ FILE *f = NULL; | |
368 | struct stat st; | |
369 | const char *p; | |
370 | uint8_t *q; | |
371 | int r; | |
372 | ||
373 | if (!c->unit) | |
374 | return 0; | |
375 | ||
376 | p = strjoina("/run/systemd/units/log-extra-fields:", c->unit); | |
377 | ||
378 | if (c->extra_fields_mtime != NSEC_INFINITY) { | |
379 | if (stat(p, &st) < 0) { | |
380 | if (errno == ENOENT) | |
381 | return 0; | |
382 | ||
383 | return -errno; | |
384 | } | |
385 | ||
386 | if (timespec_load_nsec(&st.st_mtim) == c->extra_fields_mtime) | |
387 | return 0; | |
388 | } | |
389 | ||
390 | f = fopen(p, "re"); | |
391 | if (!f) { | |
392 | if (errno == ENOENT) | |
393 | return 0; | |
394 | ||
395 | return -errno; | |
396 | } | |
397 | ||
398 | if (fstat(fileno(f), &st) < 0) /* The file might have been replaced since the stat() above, let's get a new | |
399 | * one, that matches the stuff we are reading */ | |
400 | return -errno; | |
401 | ||
402 | r = read_full_stream(f, (char**) &data, &size); | |
403 | if (r < 0) | |
404 | return r; | |
405 | ||
406 | q = data, left = size; | |
407 | while (left > 0) { | |
408 | uint8_t *field, *eq; | |
409 | uint64_t v, n; | |
410 | ||
411 | if (left < sizeof(uint64_t)) | |
412 | return -EBADMSG; | |
413 | ||
414 | v = unaligned_read_le64(q); | |
415 | if (v < 2) | |
416 | return -EBADMSG; | |
417 | ||
418 | n = sizeof(uint64_t) + v; | |
419 | if (left < n) | |
420 | return -EBADMSG; | |
421 | ||
422 | field = q + sizeof(uint64_t); | |
423 | ||
424 | eq = memchr(field, '=', v); | |
425 | if (!eq) | |
426 | return -EBADMSG; | |
427 | ||
428 | if (!journal_field_valid((const char *) field, eq - field, false)) | |
429 | return -EBADMSG; | |
430 | ||
431 | if (!GREEDY_REALLOC(iovec, n_allocated, n_iovec+1)) | |
432 | return -ENOMEM; | |
433 | ||
434 | iovec[n_iovec++] = IOVEC_MAKE(field, v); | |
435 | ||
436 | left -= n, q += n; | |
437 | } | |
438 | ||
439 | free(c->extra_fields_iovec); | |
440 | free(c->extra_fields_data); | |
441 | ||
442 | c->extra_fields_iovec = iovec; | |
443 | c->extra_fields_n_iovec = n_iovec; | |
444 | c->extra_fields_data = data; | |
445 | c->extra_fields_mtime = timespec_load_nsec(&st.st_mtim); | |
446 | ||
447 | iovec = NULL; | |
448 | data = NULL; | |
449 | ||
450 | return 0; | |
22e3a02b LP |
451 | } |
452 | ||
453 | static void client_context_really_refresh( | |
454 | Server *s, | |
455 | ClientContext *c, | |
456 | const struct ucred *ucred, | |
457 | const char *label, size_t label_size, | |
458 | const char *unit_id, | |
459 | usec_t timestamp) { | |
460 | ||
461 | assert(s); | |
462 | assert(c); | |
463 | assert(pid_is_valid(c->pid)); | |
464 | ||
465 | if (timestamp == USEC_INFINITY) | |
466 | timestamp = now(CLOCK_MONOTONIC); | |
467 | ||
468 | client_context_read_uid_gid(c, ucred); | |
469 | client_context_read_basic(c); | |
470 | (void) client_context_read_label(c, label, label_size); | |
471 | ||
472 | (void) audit_session_from_pid(c->pid, &c->auditid); | |
473 | (void) audit_loginuid_from_pid(c->pid, &c->loginuid); | |
474 | ||
475 | (void) client_context_read_cgroup(s, c, unit_id); | |
476 | (void) client_context_read_invocation_id(s, c); | |
d3070fbd LP |
477 | (void) client_context_read_log_level_max(s, c); |
478 | (void) client_context_read_extra_fields(s, c); | |
22e3a02b LP |
479 | |
480 | c->timestamp = timestamp; | |
481 | ||
482 | if (c->in_lru) { | |
483 | assert(c->n_ref == 0); | |
484 | assert_se(prioq_reshuffle(s->client_contexts_lru, c, &c->lru_index) >= 0); | |
485 | } | |
486 | } | |
487 | ||
488 | void client_context_maybe_refresh( | |
489 | Server *s, | |
490 | ClientContext *c, | |
491 | const struct ucred *ucred, | |
492 | const char *label, size_t label_size, | |
493 | const char *unit_id, | |
494 | usec_t timestamp) { | |
495 | ||
496 | assert(s); | |
497 | assert(c); | |
498 | ||
499 | if (timestamp == USEC_INFINITY) | |
500 | timestamp = now(CLOCK_MONOTONIC); | |
501 | ||
502 | /* No cached data so far? Let's fill it up */ | |
503 | if (c->timestamp == USEC_INFINITY) | |
504 | goto refresh; | |
505 | ||
506 | /* If the data isn't pinned and if the cashed data is older than the upper limit, we flush it out | |
507 | * entirely. This follows the logic that as long as an entry is pinned the PID reuse is unlikely. */ | |
508 | if (c->n_ref == 0 && c->timestamp + MAX_USEC < timestamp) { | |
509 | client_context_reset(c); | |
510 | goto refresh; | |
511 | } | |
512 | ||
513 | /* If the data is older than the lower limit, we refresh, but keep the old data for all we can't update */ | |
514 | if (c->timestamp + REFRESH_USEC < timestamp) | |
515 | goto refresh; | |
516 | ||
517 | /* If the data passed along doesn't match the cached data we also do a refresh */ | |
518 | if (ucred && uid_is_valid(ucred->uid) && c->uid != ucred->uid) | |
519 | goto refresh; | |
520 | ||
521 | if (ucred && gid_is_valid(ucred->gid) && c->gid != ucred->gid) | |
522 | goto refresh; | |
523 | ||
524 | if (label_size > 0 && (label_size != c->label_size || memcmp(label, c->label, label_size) != 0)) | |
525 | goto refresh; | |
526 | ||
527 | return; | |
528 | ||
529 | refresh: | |
530 | client_context_really_refresh(s, c, ucred, label, label_size, unit_id, timestamp); | |
531 | } | |
532 | ||
533 | static void client_context_try_shrink_to(Server *s, size_t limit) { | |
534 | assert(s); | |
535 | ||
536 | /* Bring the number of cache entries below the indicated limit, so that we can create a new entry without | |
537 | * breaching the limit. Note that we only flush out entries that aren't pinned here. This means the number of | |
538 | * cache entries may very well grow beyond the limit, if all entries stored remain pinned. */ | |
539 | ||
540 | while (hashmap_size(s->client_contexts) > limit) { | |
541 | ClientContext *c; | |
542 | ||
543 | c = prioq_pop(s->client_contexts_lru); | |
544 | if (!c) | |
545 | break; /* All remaining entries are pinned, give up */ | |
546 | ||
547 | assert(c->in_lru); | |
548 | assert(c->n_ref == 0); | |
549 | ||
550 | c->in_lru = false; | |
551 | ||
552 | client_context_free(s, c); | |
553 | } | |
554 | } | |
555 | ||
556 | void client_context_flush_all(Server *s) { | |
557 | assert(s); | |
558 | ||
559 | /* Flush out all remaining entries. This assumes all references are already dropped. */ | |
560 | ||
561 | s->my_context = client_context_release(s, s->my_context); | |
562 | s->pid1_context = client_context_release(s, s->pid1_context); | |
563 | ||
564 | client_context_try_shrink_to(s, 0); | |
565 | ||
566 | assert(prioq_size(s->client_contexts_lru) == 0); | |
567 | assert(hashmap_size(s->client_contexts) == 0); | |
568 | ||
569 | s->client_contexts_lru = prioq_free(s->client_contexts_lru); | |
570 | s->client_contexts = hashmap_free(s->client_contexts); | |
571 | } | |
572 | ||
573 | static int client_context_get_internal( | |
574 | Server *s, | |
575 | pid_t pid, | |
576 | const struct ucred *ucred, | |
577 | const char *label, size_t label_len, | |
578 | const char *unit_id, | |
579 | bool add_ref, | |
580 | ClientContext **ret) { | |
581 | ||
582 | ClientContext *c; | |
583 | int r; | |
584 | ||
585 | assert(s); | |
586 | assert(ret); | |
587 | ||
588 | if (!pid_is_valid(pid)) | |
589 | return -EINVAL; | |
590 | ||
591 | c = hashmap_get(s->client_contexts, PID_TO_PTR(pid)); | |
592 | if (c) { | |
593 | ||
594 | if (add_ref) { | |
595 | if (c->in_lru) { | |
596 | /* The entry wasn't pinned so far, let's remove it from the LRU list then */ | |
597 | assert(c->n_ref == 0); | |
598 | assert_se(prioq_remove(s->client_contexts_lru, c, &c->lru_index) >= 0); | |
599 | c->in_lru = false; | |
600 | } | |
601 | ||
602 | c->n_ref++; | |
603 | } | |
604 | ||
605 | client_context_maybe_refresh(s, c, ucred, label, label_len, unit_id, USEC_INFINITY); | |
606 | ||
607 | *ret = c; | |
608 | return 0; | |
609 | } | |
610 | ||
611 | client_context_try_shrink_to(s, CACHE_MAX-1); | |
612 | ||
613 | r = client_context_new(s, pid, &c); | |
614 | if (r < 0) | |
615 | return r; | |
616 | ||
617 | if (add_ref) | |
618 | c->n_ref++; | |
619 | else { | |
620 | r = prioq_put(s->client_contexts_lru, c, &c->lru_index); | |
621 | if (r < 0) { | |
622 | client_context_free(s, c); | |
623 | return r; | |
624 | } | |
625 | ||
626 | c->in_lru = true; | |
627 | } | |
628 | ||
629 | client_context_really_refresh(s, c, ucred, label, label_len, unit_id, USEC_INFINITY); | |
630 | ||
631 | *ret = c; | |
632 | return 0; | |
633 | } | |
634 | ||
635 | int client_context_get( | |
636 | Server *s, | |
637 | pid_t pid, | |
638 | const struct ucred *ucred, | |
639 | const char *label, size_t label_len, | |
640 | const char *unit_id, | |
641 | ClientContext **ret) { | |
642 | ||
643 | return client_context_get_internal(s, pid, ucred, label, label_len, unit_id, false, ret); | |
644 | } | |
645 | ||
646 | int client_context_acquire( | |
647 | Server *s, | |
648 | pid_t pid, | |
649 | const struct ucred *ucred, | |
650 | const char *label, size_t label_len, | |
651 | const char *unit_id, | |
652 | ClientContext **ret) { | |
653 | ||
654 | return client_context_get_internal(s, pid, ucred, label, label_len, unit_id, true, ret); | |
655 | }; | |
656 | ||
657 | ClientContext *client_context_release(Server *s, ClientContext *c) { | |
658 | assert(s); | |
659 | ||
660 | if (!c) | |
661 | return NULL; | |
662 | ||
663 | assert(c->n_ref > 0); | |
664 | assert(!c->in_lru); | |
665 | ||
666 | c->n_ref--; | |
667 | if (c->n_ref > 0) | |
668 | return NULL; | |
669 | ||
670 | /* The entry is not pinned anymore, let's add it to the LRU prioq if we can. If we can't we'll drop it | |
671 | * right-away */ | |
672 | ||
673 | if (prioq_put(s->client_contexts_lru, c, &c->lru_index) < 0) | |
674 | client_context_free(s, c); | |
675 | else | |
676 | c->in_lru = true; | |
677 | ||
678 | return NULL; | |
679 | } | |
680 | ||
681 | void client_context_acquire_default(Server *s) { | |
682 | int r; | |
683 | ||
684 | assert(s); | |
685 | ||
686 | /* Ensure that our own and PID1's contexts are always pinned. Our own context is particularly useful to | |
687 | * generate driver messages. */ | |
688 | ||
689 | if (!s->my_context) { | |
690 | struct ucred ucred = { | |
691 | .pid = getpid_cached(), | |
692 | .uid = getuid(), | |
693 | .gid = getgid(), | |
694 | }; | |
695 | ||
696 | r = client_context_acquire(s, ucred.pid, &ucred, NULL, 0, NULL, &s->my_context); | |
697 | if (r < 0) | |
698 | log_warning_errno(r, "Failed to acquire our own context, ignoring: %m"); | |
699 | } | |
700 | ||
701 | if (!s->pid1_context) { | |
702 | ||
703 | r = client_context_acquire(s, 1, NULL, NULL, 0, NULL, &s->pid1_context); | |
704 | if (r < 0) | |
705 | log_warning_errno(r, "Failed to acquire PID1's context, ignoring: %m"); | |
706 | ||
707 | } | |
708 | } |