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c798234ae90cc0a48eb68fbb9c236122c514caf2
[lttng-tools.git] / src / bin / lttng-sessiond / client.c
1 /*
2 * Copyright (C) 2011 EfficiOS Inc.
3 * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 * Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com>
5 *
6 * SPDX-License-Identifier: GPL-2.0-only
7 *
8 */
9
10 #include "common/buffer-view.h"
11 #include "common/compat/socket.h"
12 #include "common/dynamic-array.h"
13 #include "common/dynamic-buffer.h"
14 #include "common/fd-handle.h"
15 #include "common/payload-view.h"
16 #include "common/payload.h"
17 #include "common/sessiond-comm/sessiond-comm.h"
18 #include "lttng/lttng-error.h"
19 #include "lttng/tracker.h"
20 #include <common/compat/getenv.h>
21 #include <common/tracker.h>
22 #include <common/unix.h>
23 #include <common/utils.h>
24 #include <lttng/error-query-internal.h>
25 #include <lttng/event-internal.h>
26 #include <lttng/session-descriptor-internal.h>
27 #include <lttng/session-internal.h>
28 #include <lttng/userspace-probe-internal.h>
29 #include <pthread.h>
30 #include <signal.h>
31 #include <stddef.h>
32 #include <stdint.h>
33 #include <sys/stat.h>
34 #include <unistd.h>
35
36 #include "agent-thread.h"
37 #include "clear.h"
38 #include "client.h"
39 #include "cmd.h"
40 #include "health-sessiond.h"
41 #include "kernel.h"
42 #include "lttng-sessiond.h"
43 #include "manage-consumer.h"
44 #include "save.h"
45 #include "testpoint.h"
46 #include "utils.h"
47
48 static bool is_root;
49
50 static struct thread_state {
51 sem_t ready;
52 bool running;
53 int client_sock;
54 } thread_state;
55
56 static void set_thread_status(bool running)
57 {
58 DBG("Marking client thread's state as %s", running ? "running" : "error");
59 thread_state.running = running;
60 sem_post(&thread_state.ready);
61 }
62
63 static bool wait_thread_status(void)
64 {
65 DBG("Waiting for client thread to be ready");
66 sem_wait(&thread_state.ready);
67 if (thread_state.running) {
68 DBG("Client thread is ready");
69 } else {
70 ERR("Initialization of client thread failed");
71 }
72
73 return thread_state.running;
74 }
75
76 /*
77 * Setup the outgoing data buffer for the response (llm) by allocating the
78 * right amount of memory and copying the original information from the lsm
79 * structure.
80 *
81 * Return 0 on success, negative value on error.
82 */
83 static int setup_lttng_msg(struct command_ctx *cmd_ctx,
84 const void *payload_buf, size_t payload_len,
85 const void *cmd_header_buf, size_t cmd_header_len)
86 {
87 int ret = 0;
88 const size_t header_len = sizeof(struct lttcomm_lttng_msg);
89 const size_t total_msg_size = header_len + cmd_header_len + payload_len;
90 const struct lttcomm_lttng_msg llm = {
91 .cmd_type = cmd_ctx->lsm.cmd_type,
92 .pid = cmd_ctx->lsm.domain.attr.pid,
93 .cmd_header_size = cmd_header_len,
94 .data_size = payload_len,
95 };
96
97 ret = lttng_dynamic_buffer_set_size(&cmd_ctx->reply_payload.buffer, 0);
98 if (ret) {
99 goto end;
100 }
101
102 lttng_dynamic_pointer_array_clear(&cmd_ctx->reply_payload._fd_handles);
103
104 cmd_ctx->lttng_msg_size = total_msg_size;
105
106 /* Append reply header. */
107 ret = lttng_dynamic_buffer_append(
108 &cmd_ctx->reply_payload.buffer, &llm, sizeof(llm));
109 if (ret) {
110 goto end;
111 }
112
113 /* Append command header. */
114 if (cmd_header_len) {
115 ret = lttng_dynamic_buffer_append(
116 &cmd_ctx->reply_payload.buffer, cmd_header_buf,
117 cmd_header_len);
118 if (ret) {
119 goto end;
120 }
121 }
122
123 /* Append payload. */
124 if (payload_len) {
125 ret = lttng_dynamic_buffer_append(
126 &cmd_ctx->reply_payload.buffer, payload_buf,
127 payload_len);
128 if (ret) {
129 goto end;
130 }
131 }
132
133 end:
134 return ret;
135 }
136
137 static int setup_empty_lttng_msg(struct command_ctx *cmd_ctx)
138 {
139 int ret;
140 const struct lttcomm_lttng_msg llm = {};
141
142 ret = lttng_dynamic_buffer_set_size(&cmd_ctx->reply_payload.buffer, 0);
143 if (ret) {
144 goto end;
145 }
146
147 /* Append place-holder reply header. */
148 ret = lttng_dynamic_buffer_append(
149 &cmd_ctx->reply_payload.buffer, &llm, sizeof(llm));
150 if (ret) {
151 goto end;
152 }
153
154 cmd_ctx->lttng_msg_size = sizeof(llm);
155 end:
156 return ret;
157 }
158
159 static void update_lttng_msg(struct command_ctx *cmd_ctx, size_t cmd_header_len,
160 size_t payload_len)
161 {
162 const size_t header_len = sizeof(struct lttcomm_lttng_msg);
163 const size_t total_msg_size = header_len + cmd_header_len + payload_len;
164 const struct lttcomm_lttng_msg llm = {
165 .cmd_type = cmd_ctx->lsm.cmd_type,
166 .pid = cmd_ctx->lsm.domain.attr.pid,
167 .cmd_header_size = cmd_header_len,
168 .data_size = payload_len,
169 };
170 struct lttcomm_lttng_msg *p_llm;
171
172 assert(cmd_ctx->reply_payload.buffer.size >= sizeof(llm));
173
174 p_llm = (typeof(p_llm)) cmd_ctx->reply_payload.buffer.data;
175
176 /* Update existing header. */
177 memcpy(p_llm, &llm, sizeof(llm));
178
179 cmd_ctx->lttng_msg_size = total_msg_size;
180 }
181
182 /*
183 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
184 * exec or it will fail.
185 */
186 static int spawn_consumer_thread(struct consumer_data *consumer_data)
187 {
188 return launch_consumer_management_thread(consumer_data) ? 0 : -1;
189 }
190
191 /*
192 * Fork and exec a consumer daemon (consumerd).
193 *
194 * Return pid if successful else -1.
195 */
196 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
197 {
198 int ret;
199 pid_t pid;
200 const char *consumer_to_use;
201 const char *verbosity;
202 struct stat st;
203
204 DBG("Spawning consumerd");
205
206 pid = fork();
207 if (pid == 0) {
208 /*
209 * Exec consumerd.
210 */
211 if (the_config.verbose_consumer) {
212 verbosity = "--verbose";
213 } else if (lttng_opt_quiet) {
214 verbosity = "--quiet";
215 } else {
216 verbosity = "";
217 }
218
219 switch (consumer_data->type) {
220 case LTTNG_CONSUMER_KERNEL:
221 /*
222 * Find out which consumerd to execute. We will first try the
223 * 64-bit path, then the sessiond's installation directory, and
224 * fallback on the 32-bit one,
225 */
226 DBG3("Looking for a kernel consumer at these locations:");
227 DBG3(" 1) %s", the_config.consumerd64_bin_path.value ? : "NULL");
228 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, DEFAULT_CONSUMERD_FILE);
229 DBG3(" 3) %s", the_config.consumerd32_bin_path.value ? : "NULL");
230 if (stat(the_config.consumerd64_bin_path.value, &st) == 0) {
231 DBG3("Found location #1");
232 consumer_to_use = the_config.consumerd64_bin_path.value;
233 } else if (stat(INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE, &st) == 0) {
234 DBG3("Found location #2");
235 consumer_to_use = INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE;
236 } else if (the_config.consumerd32_bin_path.value &&
237 stat(the_config.consumerd32_bin_path.value, &st) == 0) {
238 DBG3("Found location #3");
239 consumer_to_use = the_config.consumerd32_bin_path.value;
240 } else {
241 DBG("Could not find any valid consumerd executable");
242 ret = -EINVAL;
243 goto error;
244 }
245 DBG("Using kernel consumer at: %s", consumer_to_use);
246 (void) execl(consumer_to_use, "lttng-consumerd",
247 verbosity, "-k", "--consumerd-cmd-sock",
248 consumer_data->cmd_unix_sock_path,
249 "--consumerd-err-sock",
250 consumer_data->err_unix_sock_path,
251 "--group",
252 the_config.tracing_group_name.value,
253 NULL);
254 break;
255 case LTTNG_CONSUMER64_UST:
256 {
257 if (the_config.consumerd64_lib_dir.value) {
258 const char *tmp;
259 size_t tmplen;
260 char *tmpnew;
261
262 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
263 if (!tmp) {
264 tmp = "";
265 }
266 tmplen = strlen(the_config.consumerd64_lib_dir.value) + 1 /* : */ + strlen(tmp);
267 tmpnew = zmalloc(tmplen + 1 /* \0 */);
268 if (!tmpnew) {
269 ret = -ENOMEM;
270 goto error;
271 }
272 strcat(tmpnew, the_config.consumerd64_lib_dir.value);
273 if (tmp[0] != '\0') {
274 strcat(tmpnew, ":");
275 strcat(tmpnew, tmp);
276 }
277 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
278 free(tmpnew);
279 if (ret) {
280 ret = -errno;
281 goto error;
282 }
283 }
284 DBG("Using 64-bit UST consumer at: %s",
285 the_config.consumerd64_bin_path.value);
286 (void) execl(the_config.consumerd64_bin_path.value,
287 "lttng-consumerd", verbosity, "-u",
288 "--consumerd-cmd-sock",
289 consumer_data->cmd_unix_sock_path,
290 "--consumerd-err-sock",
291 consumer_data->err_unix_sock_path,
292 "--group",
293 the_config.tracing_group_name.value,
294 NULL);
295 break;
296 }
297 case LTTNG_CONSUMER32_UST:
298 {
299 if (the_config.consumerd32_lib_dir.value) {
300 const char *tmp;
301 size_t tmplen;
302 char *tmpnew;
303
304 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
305 if (!tmp) {
306 tmp = "";
307 }
308 tmplen = strlen(the_config.consumerd32_lib_dir.value) + 1 /* : */ + strlen(tmp);
309 tmpnew = zmalloc(tmplen + 1 /* \0 */);
310 if (!tmpnew) {
311 ret = -ENOMEM;
312 goto error;
313 }
314 strcat(tmpnew, the_config.consumerd32_lib_dir.value);
315 if (tmp[0] != '\0') {
316 strcat(tmpnew, ":");
317 strcat(tmpnew, tmp);
318 }
319 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
320 free(tmpnew);
321 if (ret) {
322 ret = -errno;
323 goto error;
324 }
325 }
326 DBG("Using 32-bit UST consumer at: %s",
327 the_config.consumerd32_bin_path.value);
328 (void) execl(the_config.consumerd32_bin_path.value,
329 "lttng-consumerd", verbosity, "-u",
330 "--consumerd-cmd-sock",
331 consumer_data->cmd_unix_sock_path,
332 "--consumerd-err-sock",
333 consumer_data->err_unix_sock_path,
334 "--group",
335 the_config.tracing_group_name.value,
336 NULL);
337 break;
338 }
339 default:
340 ERR("unknown consumer type");
341 errno = 0;
342 }
343 if (errno != 0) {
344 PERROR("Consumer execl()");
345 }
346 /* Reaching this point, we got a failure on our execl(). */
347 exit(EXIT_FAILURE);
348 } else if (pid > 0) {
349 ret = pid;
350 } else {
351 PERROR("start consumer fork");
352 ret = -errno;
353 }
354 error:
355 return ret;
356 }
357
358 /*
359 * Spawn the consumerd daemon and session daemon thread.
360 */
361 static int start_consumerd(struct consumer_data *consumer_data)
362 {
363 int ret;
364
365 /*
366 * Set the listen() state on the socket since there is a possible race
367 * between the exec() of the consumer daemon and this call if place in the
368 * consumer thread. See bug #366 for more details.
369 */
370 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
371 if (ret < 0) {
372 goto error;
373 }
374
375 pthread_mutex_lock(&consumer_data->pid_mutex);
376 if (consumer_data->pid != 0) {
377 pthread_mutex_unlock(&consumer_data->pid_mutex);
378 goto end;
379 }
380
381 ret = spawn_consumerd(consumer_data);
382 if (ret < 0) {
383 ERR("Spawning consumerd failed");
384 pthread_mutex_unlock(&consumer_data->pid_mutex);
385 goto error;
386 }
387
388 /* Setting up the consumer_data pid */
389 consumer_data->pid = ret;
390 DBG2("Consumer pid %d", consumer_data->pid);
391 pthread_mutex_unlock(&consumer_data->pid_mutex);
392
393 DBG2("Spawning consumer control thread");
394 ret = spawn_consumer_thread(consumer_data);
395 if (ret < 0) {
396 ERR("Fatal error spawning consumer control thread");
397 goto error;
398 }
399
400 end:
401 return 0;
402
403 error:
404 /* Cleanup already created sockets on error. */
405 if (consumer_data->err_sock >= 0) {
406 int err;
407
408 err = close(consumer_data->err_sock);
409 if (err < 0) {
410 PERROR("close consumer data error socket");
411 }
412 }
413 return ret;
414 }
415
416 /*
417 * Copy consumer output from the tracing session to the domain session. The
418 * function also applies the right modification on a per domain basis for the
419 * trace files destination directory.
420 *
421 * Should *NOT* be called with RCU read-side lock held.
422 */
423 static int copy_session_consumer(int domain, struct ltt_session *session)
424 {
425 int ret;
426 const char *dir_name;
427 struct consumer_output *consumer;
428
429 assert(session);
430 assert(session->consumer);
431
432 switch (domain) {
433 case LTTNG_DOMAIN_KERNEL:
434 DBG3("Copying tracing session consumer output in kernel session");
435 /*
436 * XXX: We should audit the session creation and what this function
437 * does "extra" in order to avoid a destroy since this function is used
438 * in the domain session creation (kernel and ust) only. Same for UST
439 * domain.
440 */
441 if (session->kernel_session->consumer) {
442 consumer_output_put(session->kernel_session->consumer);
443 }
444 session->kernel_session->consumer =
445 consumer_copy_output(session->consumer);
446 /* Ease our life a bit for the next part */
447 consumer = session->kernel_session->consumer;
448 dir_name = DEFAULT_KERNEL_TRACE_DIR;
449 break;
450 case LTTNG_DOMAIN_JUL:
451 case LTTNG_DOMAIN_LOG4J:
452 case LTTNG_DOMAIN_PYTHON:
453 case LTTNG_DOMAIN_UST:
454 DBG3("Copying tracing session consumer output in UST session");
455 if (session->ust_session->consumer) {
456 consumer_output_put(session->ust_session->consumer);
457 }
458 session->ust_session->consumer =
459 consumer_copy_output(session->consumer);
460 /* Ease our life a bit for the next part */
461 consumer = session->ust_session->consumer;
462 dir_name = DEFAULT_UST_TRACE_DIR;
463 break;
464 default:
465 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
466 goto error;
467 }
468
469 /* Append correct directory to subdir */
470 ret = lttng_strncpy(consumer->domain_subdir, dir_name,
471 sizeof(consumer->domain_subdir));
472 if (ret) {
473 ret = LTTNG_ERR_UNK;
474 goto error;
475 }
476 DBG3("Copy session consumer subdir %s", consumer->domain_subdir);
477 ret = LTTNG_OK;
478
479 error:
480 return ret;
481 }
482
483 /*
484 * Create an UST session and add it to the session ust list.
485 *
486 * Should *NOT* be called with RCU read-side lock held.
487 */
488 static int create_ust_session(struct ltt_session *session,
489 const struct lttng_domain *domain)
490 {
491 int ret;
492 struct ltt_ust_session *lus = NULL;
493
494 assert(session);
495 assert(domain);
496 assert(session->consumer);
497
498 switch (domain->type) {
499 case LTTNG_DOMAIN_JUL:
500 case LTTNG_DOMAIN_LOG4J:
501 case LTTNG_DOMAIN_PYTHON:
502 case LTTNG_DOMAIN_UST:
503 break;
504 default:
505 ERR("Unknown UST domain on create session %d", domain->type);
506 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
507 goto error;
508 }
509
510 DBG("Creating UST session");
511
512 lus = trace_ust_create_session(session->id);
513 if (lus == NULL) {
514 ret = LTTNG_ERR_UST_SESS_FAIL;
515 goto error;
516 }
517
518 lus->uid = session->uid;
519 lus->gid = session->gid;
520 lus->output_traces = session->output_traces;
521 lus->snapshot_mode = session->snapshot_mode;
522 lus->live_timer_interval = session->live_timer;
523 session->ust_session = lus;
524 if (session->shm_path[0]) {
525 strncpy(lus->root_shm_path, session->shm_path,
526 sizeof(lus->root_shm_path));
527 lus->root_shm_path[sizeof(lus->root_shm_path) - 1] = '\0';
528 strncpy(lus->shm_path, session->shm_path,
529 sizeof(lus->shm_path));
530 lus->shm_path[sizeof(lus->shm_path) - 1] = '\0';
531 strncat(lus->shm_path, "/ust",
532 sizeof(lus->shm_path) - strlen(lus->shm_path) - 1);
533 }
534 /* Copy session output to the newly created UST session */
535 ret = copy_session_consumer(domain->type, session);
536 if (ret != LTTNG_OK) {
537 goto error;
538 }
539
540 return LTTNG_OK;
541
542 error:
543 free(lus);
544 session->ust_session = NULL;
545 return ret;
546 }
547
548 /*
549 * Create a kernel tracer session then create the default channel.
550 */
551 static int create_kernel_session(struct ltt_session *session)
552 {
553 int ret;
554
555 DBG("Creating kernel session");
556
557 ret = kernel_create_session(session);
558 if (ret < 0) {
559 ret = LTTNG_ERR_KERN_SESS_FAIL;
560 goto error_create;
561 }
562
563 /* Code flow safety */
564 assert(session->kernel_session);
565
566 /* Copy session output to the newly created Kernel session */
567 ret = copy_session_consumer(LTTNG_DOMAIN_KERNEL, session);
568 if (ret != LTTNG_OK) {
569 goto error;
570 }
571
572 session->kernel_session->uid = session->uid;
573 session->kernel_session->gid = session->gid;
574 session->kernel_session->output_traces = session->output_traces;
575 session->kernel_session->snapshot_mode = session->snapshot_mode;
576 session->kernel_session->is_live_session = session->live_timer != 0;
577
578 return LTTNG_OK;
579
580 error:
581 trace_kernel_destroy_session(session->kernel_session);
582 session->kernel_session = NULL;
583 error_create:
584 return ret;
585 }
586
587 /*
588 * Count number of session permitted by uid/gid.
589 */
590 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
591 {
592 unsigned int i = 0;
593 struct ltt_session *session;
594 const struct ltt_session_list *session_list = session_get_list();
595
596 DBG("Counting number of available session for UID %d", uid);
597 cds_list_for_each_entry(session, &session_list->head, list) {
598 if (!session_get(session)) {
599 continue;
600 }
601 session_lock(session);
602 /* Only count the sessions the user can control. */
603 if (session_access_ok(session, uid) &&
604 !session->destroyed) {
605 i++;
606 }
607 session_unlock(session);
608 session_put(session);
609 }
610 return i;
611 }
612
613 static enum lttng_error_code receive_lttng_trigger(struct command_ctx *cmd_ctx,
614 int sock,
615 int *sock_error,
616 struct lttng_trigger **_trigger)
617 {
618 int ret;
619 size_t trigger_len;
620 ssize_t sock_recv_len;
621 enum lttng_error_code ret_code;
622 struct lttng_payload trigger_payload;
623 struct lttng_trigger *trigger = NULL;
624
625 lttng_payload_init(&trigger_payload);
626 trigger_len = (size_t) cmd_ctx->lsm.u.trigger.length;
627 ret = lttng_dynamic_buffer_set_size(
628 &trigger_payload.buffer, trigger_len);
629 if (ret) {
630 ret_code = LTTNG_ERR_NOMEM;
631 goto end;
632 }
633
634 sock_recv_len = lttcomm_recv_unix_sock(
635 sock, trigger_payload.buffer.data, trigger_len);
636 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
637 ERR("Failed to receive trigger in command payload");
638 *sock_error = 1;
639 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
640 goto end;
641 }
642
643 /* Receive fds, if any. */
644 if (cmd_ctx->lsm.fd_count > 0) {
645 sock_recv_len = lttcomm_recv_payload_fds_unix_sock(
646 sock, cmd_ctx->lsm.fd_count, &trigger_payload);
647 if (sock_recv_len > 0 &&
648 sock_recv_len != cmd_ctx->lsm.fd_count * sizeof(int)) {
649 ERR("Failed to receive all file descriptors for trigger in command payload: expected fd count = %u, ret = %d",
650 cmd_ctx->lsm.fd_count, (int) ret);
651 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
652 *sock_error = 1;
653 goto end;
654 } else if (sock_recv_len <= 0) {
655 ERR("Failed to receive file descriptors for trigger in command payload: expected fd count = %u, ret = %d",
656 cmd_ctx->lsm.fd_count, (int) ret);
657 ret_code = LTTNG_ERR_FATAL;
658 *sock_error = 1;
659 goto end;
660 }
661 }
662
663 /* Deserialize trigger. */
664 {
665 struct lttng_payload_view view =
666 lttng_payload_view_from_payload(
667 &trigger_payload, 0, -1);
668
669 if (lttng_trigger_create_from_payload(&view, &trigger) !=
670 trigger_len) {
671 ERR("Invalid trigger received as part of command payload");
672 ret_code = LTTNG_ERR_INVALID_TRIGGER;
673 lttng_trigger_put(trigger);
674 goto end;
675 }
676 }
677
678 *_trigger = trigger;
679 ret_code = LTTNG_OK;
680
681 end:
682 lttng_payload_reset(&trigger_payload);
683 return ret_code;
684 }
685
686 static enum lttng_error_code receive_lttng_error_query(struct command_ctx *cmd_ctx,
687 int sock,
688 int *sock_error,
689 struct lttng_error_query **_query)
690 {
691 int ret;
692 size_t query_len;
693 ssize_t sock_recv_len;
694 enum lttng_error_code ret_code;
695 struct lttng_payload query_payload;
696 struct lttng_error_query *query = NULL;
697
698 lttng_payload_init(&query_payload);
699 query_len = (size_t) cmd_ctx->lsm.u.error_query.length;
700 ret = lttng_dynamic_buffer_set_size(&query_payload.buffer, query_len);
701 if (ret) {
702 ret_code = LTTNG_ERR_NOMEM;
703 goto end;
704 }
705
706 sock_recv_len = lttcomm_recv_unix_sock(
707 sock, query_payload.buffer.data, query_len);
708 if (sock_recv_len < 0 || sock_recv_len != query_len) {
709 ERR("Failed to receive error query in command payload");
710 *sock_error = 1;
711 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
712 goto end;
713 }
714
715 /* Receive fds, if any. */
716 if (cmd_ctx->lsm.fd_count > 0) {
717 sock_recv_len = lttcomm_recv_payload_fds_unix_sock(
718 sock, cmd_ctx->lsm.fd_count, &query_payload);
719 if (sock_recv_len > 0 &&
720 sock_recv_len != cmd_ctx->lsm.fd_count * sizeof(int)) {
721 ERR("Failed to receive all file descriptors for error query in command payload: expected fd count = %u, ret = %d",
722 cmd_ctx->lsm.fd_count, (int) ret);
723 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
724 *sock_error = 1;
725 goto end;
726 } else if (sock_recv_len <= 0) {
727 ERR("Failed to receive file descriptors for error query in command payload: expected fd count = %u, ret = %d",
728 cmd_ctx->lsm.fd_count, (int) ret);
729 ret_code = LTTNG_ERR_FATAL;
730 *sock_error = 1;
731 goto end;
732 }
733 }
734
735 /* Deserialize error query. */
736 {
737 struct lttng_payload_view view =
738 lttng_payload_view_from_payload(
739 &query_payload, 0, -1);
740
741 if (lttng_error_query_create_from_payload(&view, &query) !=
742 query_len) {
743 ERR("Invalid error query received as part of command payload");
744 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
745 goto end;
746 }
747 }
748
749 *_query = query;
750 ret_code = LTTNG_OK;
751
752 end:
753 lttng_payload_reset(&query_payload);
754 return ret_code;
755 }
756
757 static enum lttng_error_code receive_lttng_event(struct command_ctx *cmd_ctx,
758 int sock,
759 int *sock_error,
760 struct lttng_event **out_event,
761 char **out_filter_expression,
762 struct lttng_bytecode **out_bytecode,
763 struct lttng_event_exclusion **out_exclusion)
764 {
765 int ret;
766 size_t event_len;
767 ssize_t sock_recv_len;
768 enum lttng_error_code ret_code;
769 struct lttng_payload event_payload;
770 struct lttng_event *local_event = NULL;
771 char *local_filter_expression = NULL;
772 struct lttng_bytecode *local_bytecode = NULL;
773 struct lttng_event_exclusion *local_exclusion = NULL;
774
775 lttng_payload_init(&event_payload);
776 if (cmd_ctx->lsm.cmd_type == LTTNG_ENABLE_EVENT) {
777 event_len = (size_t) cmd_ctx->lsm.u.enable.length;
778 } else if (cmd_ctx->lsm.cmd_type == LTTNG_DISABLE_EVENT) {
779 event_len = (size_t) cmd_ctx->lsm.u.disable.length;
780 } else {
781 abort();
782 }
783
784 ret = lttng_dynamic_buffer_set_size(&event_payload.buffer, event_len);
785 if (ret) {
786 ret_code = LTTNG_ERR_NOMEM;
787 goto end;
788 }
789
790 sock_recv_len = lttcomm_recv_unix_sock(
791 sock, event_payload.buffer.data, event_len);
792 if (sock_recv_len < 0 || sock_recv_len != event_len) {
793 ERR("Failed to receive event in command payload");
794 *sock_error = 1;
795 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
796 goto end;
797 }
798
799 /* Receive fds, if any. */
800 if (cmd_ctx->lsm.fd_count > 0) {
801 sock_recv_len = lttcomm_recv_payload_fds_unix_sock(
802 sock, cmd_ctx->lsm.fd_count, &event_payload);
803 if (sock_recv_len > 0 &&
804 sock_recv_len != cmd_ctx->lsm.fd_count * sizeof(int)) {
805 ERR("Failed to receive all file descriptors for event in command payload: expected fd count = %u, ret = %d",
806 cmd_ctx->lsm.fd_count, (int) ret);
807 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
808 *sock_error = 1;
809 goto end;
810 } else if (sock_recv_len <= 0) {
811 ERR("Failed to receive file descriptors for event in command payload: expected fd count = %u, ret = %d",
812 cmd_ctx->lsm.fd_count, (int) ret);
813 ret_code = LTTNG_ERR_FATAL;
814 *sock_error = 1;
815 goto end;
816 }
817 }
818
819 /* Deserialize event. */
820 {
821 ssize_t len;
822 struct lttng_payload_view event_view =
823 lttng_payload_view_from_payload(
824 &event_payload, 0, -1);
825
826 len = lttng_event_create_from_payload(&event_view, &local_event,
827 &local_exclusion, &local_filter_expression,
828 &local_bytecode);
829
830 if (len < 0) {
831 ERR("Failed to create an event from the received buffer");
832 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
833 goto end;
834 }
835
836 if (len != event_len) {
837 ERR("Userspace probe location from the received buffer is not the advertised length: header length = %zu" PRIu32 ", payload length = %zd", event_len, len);
838 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
839 goto end;
840 }
841 }
842
843 *out_event = local_event;
844 *out_exclusion = local_exclusion;
845 *out_filter_expression = local_filter_expression;
846 *out_bytecode = local_bytecode;
847 local_event = NULL;
848 local_exclusion = NULL;
849 local_filter_expression = NULL;
850 local_bytecode = NULL;
851
852 ret_code = LTTNG_OK;
853
854 end:
855 lttng_payload_reset(&event_payload);
856 lttng_event_destroy(local_event);
857 free(local_filter_expression);
858 free(local_bytecode);
859 free(local_exclusion);
860 return ret_code;
861 }
862
863 static enum lttng_error_code receive_lttng_event_context(
864 const struct command_ctx *cmd_ctx,
865 int sock,
866 int *sock_error,
867 struct lttng_event_context **out_event_context)
868 {
869 int ret;
870 const size_t event_context_len =
871 (size_t) cmd_ctx->lsm.u.context.length;
872 ssize_t sock_recv_len;
873 enum lttng_error_code ret_code;
874 struct lttng_payload event_context_payload;
875 struct lttng_event_context *context = NULL;
876
877 lttng_payload_init(&event_context_payload);
878
879 ret = lttng_dynamic_buffer_set_size(&event_context_payload.buffer,
880 event_context_len);
881 if (ret) {
882 ret_code = LTTNG_ERR_NOMEM;
883 goto end;
884 }
885
886 sock_recv_len = lttcomm_recv_unix_sock(
887 sock, event_context_payload.buffer.data,
888 event_context_len);
889 if (sock_recv_len < 0 || sock_recv_len != event_context_len) {
890 ERR("Failed to receive event context in command payload");
891 *sock_error = 1;
892 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
893 goto end;
894 }
895
896 /* Deserialize event. */
897 {
898 ssize_t len;
899 struct lttng_payload_view event_context_view =
900 lttng_payload_view_from_payload(
901 &event_context_payload, 0, -1);
902
903 len = lttng_event_context_create_from_payload(
904 &event_context_view, &context);
905
906 if (len < 0) {
907 ERR("Failed to create a event context from the received buffer");
908 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
909 goto end;
910 }
911
912 if (len != event_context_len) {
913 ERR("Event context from the received buffer is not the advertised length: expected length = %zu, payload length = %zd", event_context_len, len);
914 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
915 goto end;
916 }
917 }
918
919 *out_event_context = context;
920 context = NULL;
921 ret_code = LTTNG_OK;
922
923 end:
924 lttng_event_context_destroy(context);
925 lttng_payload_reset(&event_context_payload);
926 return ret_code;
927 }
928
929 /*
930 * Version of setup_lttng_msg() without command header.
931 */
932 static int setup_lttng_msg_no_cmd_header(struct command_ctx *cmd_ctx,
933 void *payload_buf, size_t payload_len)
934 {
935 return setup_lttng_msg(cmd_ctx, payload_buf, payload_len, NULL, 0);
936 }
937
938 /*
939 * Check if the current kernel tracer supports the session rotation feature.
940 * Return 1 if it does, 0 otherwise.
941 */
942 static int check_rotate_compatible(void)
943 {
944 int ret = 1;
945
946 if (the_kernel_tracer_version.major != 2 ||
947 the_kernel_tracer_version.minor < 11) {
948 DBG("Kernel tracer version is not compatible with the rotation feature");
949 ret = 0;
950 }
951
952 return ret;
953 }
954
955 /*
956 * Send data on a unix socket using the liblttsessiondcomm API.
957 *
958 * Return lttcomm error code.
959 */
960 static int send_unix_sock(int sock, struct lttng_payload_view *view)
961 {
962 int ret;
963 const int fd_count = lttng_payload_view_get_fd_handle_count(view);
964
965 /* Check valid length */
966 if (view->buffer.size == 0) {
967 ret = -1;
968 goto end;
969 }
970
971 ret = lttcomm_send_unix_sock(
972 sock, view->buffer.data, view->buffer.size);
973 if (ret < 0) {
974 goto end;
975 }
976
977 if (fd_count > 0) {
978 ret = lttcomm_send_payload_view_fds_unix_sock(sock, view);
979 if (ret < 0) {
980 goto end;
981 }
982 }
983
984 end:
985 return ret;
986 }
987
988 /*
989 * Process the command requested by the lttng client within the command
990 * context structure. This function make sure that the return structure (llm)
991 * is set and ready for transmission before returning.
992 *
993 * Return any error encountered or 0 for success.
994 *
995 * "sock" is only used for special-case var. len data.
996 * A command may assume the ownership of the socket, in which case its value
997 * should be set to -1.
998 *
999 * Should *NOT* be called with RCU read-side lock held.
1000 */
1001 static int process_client_msg(struct command_ctx *cmd_ctx, int *sock,
1002 int *sock_error)
1003 {
1004 int ret = LTTNG_OK;
1005 bool need_tracing_session = true;
1006 bool need_domain;
1007 bool need_consumerd;
1008
1009 if (!lttcomm_sessiond_command_is_valid((enum lttcomm_sessiond_command) cmd_ctx->lsm.cmd_type)) {
1010 ERR("Unknown client command received: command id = %" PRIu32,
1011 cmd_ctx->lsm.cmd_type);
1012 ret = LTTNG_ERR_UND;
1013 goto error;
1014 }
1015
1016 DBG("Processing client command '%s\' (%d)",
1017 lttcomm_sessiond_command_str(cmd_ctx->lsm.cmd_type),
1018 cmd_ctx->lsm.cmd_type);
1019
1020 assert(!rcu_read_ongoing());
1021
1022 *sock_error = 0;
1023
1024 switch (cmd_ctx->lsm.cmd_type) {
1025 case LTTNG_CREATE_SESSION_EXT:
1026 case LTTNG_DESTROY_SESSION:
1027 case LTTNG_LIST_SESSIONS:
1028 case LTTNG_LIST_DOMAINS:
1029 case LTTNG_START_TRACE:
1030 case LTTNG_STOP_TRACE:
1031 case LTTNG_DATA_PENDING:
1032 case LTTNG_SNAPSHOT_ADD_OUTPUT:
1033 case LTTNG_SNAPSHOT_DEL_OUTPUT:
1034 case LTTNG_SNAPSHOT_LIST_OUTPUT:
1035 case LTTNG_SNAPSHOT_RECORD:
1036 case LTTNG_SAVE_SESSION:
1037 case LTTNG_SET_SESSION_SHM_PATH:
1038 case LTTNG_REGENERATE_METADATA:
1039 case LTTNG_REGENERATE_STATEDUMP:
1040 case LTTNG_ROTATE_SESSION:
1041 case LTTNG_ROTATION_GET_INFO:
1042 case LTTNG_ROTATION_SET_SCHEDULE:
1043 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
1044 case LTTNG_CLEAR_SESSION:
1045 case LTTNG_LIST_TRIGGERS:
1046 case LTTNG_EXECUTE_ERROR_QUERY:
1047 need_domain = false;
1048 break;
1049 default:
1050 need_domain = true;
1051 }
1052
1053 /* Needs a functioning consumerd? */
1054 switch (cmd_ctx->lsm.cmd_type) {
1055 case LTTNG_REGISTER_TRIGGER:
1056 case LTTNG_UNREGISTER_TRIGGER:
1057 case LTTNG_EXECUTE_ERROR_QUERY:
1058 need_consumerd = false;
1059 break;
1060 default:
1061 need_consumerd = true;
1062 break;
1063 }
1064
1065 if (the_config.no_kernel && need_domain &&
1066 cmd_ctx->lsm.domain.type == LTTNG_DOMAIN_KERNEL) {
1067 if (!is_root) {
1068 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
1069 } else {
1070 ret = LTTNG_ERR_KERN_NA;
1071 }
1072 goto error;
1073 }
1074
1075 /* Deny register consumer if we already have a spawned consumer. */
1076 if (cmd_ctx->lsm.cmd_type == LTTNG_REGISTER_CONSUMER) {
1077 pthread_mutex_lock(&the_kconsumer_data.pid_mutex);
1078 if (the_kconsumer_data.pid > 0) {
1079 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
1080 pthread_mutex_unlock(&the_kconsumer_data.pid_mutex);
1081 goto error;
1082 }
1083 pthread_mutex_unlock(&the_kconsumer_data.pid_mutex);
1084 }
1085
1086 /*
1087 * Check for command that don't needs to allocate a returned payload. We do
1088 * this here so we don't have to make the call for no payload at each
1089 * command.
1090 */
1091 switch(cmd_ctx->lsm.cmd_type) {
1092 case LTTNG_LIST_SESSIONS:
1093 case LTTNG_LIST_TRACEPOINTS:
1094 case LTTNG_LIST_TRACEPOINT_FIELDS:
1095 case LTTNG_LIST_DOMAINS:
1096 case LTTNG_LIST_CHANNELS:
1097 case LTTNG_LIST_EVENTS:
1098 case LTTNG_LIST_SYSCALLS:
1099 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
1100 case LTTNG_PROCESS_ATTR_TRACKER_GET_POLICY:
1101 case LTTNG_PROCESS_ATTR_TRACKER_GET_INCLUSION_SET:
1102 case LTTNG_DATA_PENDING:
1103 case LTTNG_ROTATE_SESSION:
1104 case LTTNG_ROTATION_GET_INFO:
1105 case LTTNG_REGISTER_TRIGGER:
1106 case LTTNG_LIST_TRIGGERS:
1107 case LTTNG_EXECUTE_ERROR_QUERY:
1108 break;
1109 default:
1110 /* Setup lttng message with no payload */
1111 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0);
1112 if (ret < 0) {
1113 /* This label does not try to unlock the session */
1114 goto init_setup_error;
1115 }
1116 }
1117
1118 /* Commands that DO NOT need a session. */
1119 switch (cmd_ctx->lsm.cmd_type) {
1120 case LTTNG_CREATE_SESSION_EXT:
1121 case LTTNG_LIST_SESSIONS:
1122 case LTTNG_LIST_TRACEPOINTS:
1123 case LTTNG_LIST_SYSCALLS:
1124 case LTTNG_LIST_TRACEPOINT_FIELDS:
1125 case LTTNG_SAVE_SESSION:
1126 case LTTNG_REGISTER_TRIGGER:
1127 case LTTNG_UNREGISTER_TRIGGER:
1128 case LTTNG_LIST_TRIGGERS:
1129 case LTTNG_EXECUTE_ERROR_QUERY:
1130 need_tracing_session = false;
1131 break;
1132 default:
1133 DBG("Getting session %s by name", cmd_ctx->lsm.session.name);
1134 /*
1135 * We keep the session list lock across _all_ commands
1136 * for now, because the per-session lock does not
1137 * handle teardown properly.
1138 */
1139 session_lock_list();
1140 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm.session.name);
1141 if (cmd_ctx->session == NULL) {
1142 ret = LTTNG_ERR_SESS_NOT_FOUND;
1143 goto error;
1144 } else {
1145 /* Acquire lock for the session */
1146 session_lock(cmd_ctx->session);
1147 }
1148 break;
1149 }
1150
1151 /*
1152 * Commands that need a valid session but should NOT create one if none
1153 * exists. Instead of creating one and destroying it when the command is
1154 * handled, process that right before so we save some round trip in useless
1155 * code path.
1156 */
1157 switch (cmd_ctx->lsm.cmd_type) {
1158 case LTTNG_DISABLE_CHANNEL:
1159 case LTTNG_DISABLE_EVENT:
1160 switch (cmd_ctx->lsm.domain.type) {
1161 case LTTNG_DOMAIN_KERNEL:
1162 if (!cmd_ctx->session->kernel_session) {
1163 ret = LTTNG_ERR_NO_CHANNEL;
1164 goto error;
1165 }
1166 break;
1167 case LTTNG_DOMAIN_JUL:
1168 case LTTNG_DOMAIN_LOG4J:
1169 case LTTNG_DOMAIN_PYTHON:
1170 case LTTNG_DOMAIN_UST:
1171 if (!cmd_ctx->session->ust_session) {
1172 ret = LTTNG_ERR_NO_CHANNEL;
1173 goto error;
1174 }
1175 break;
1176 default:
1177 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1178 goto error;
1179 }
1180 default:
1181 break;
1182 }
1183
1184 if (!need_domain) {
1185 goto skip_domain;
1186 }
1187
1188 /*
1189 * Check domain type for specific "pre-action".
1190 */
1191 switch (cmd_ctx->lsm.domain.type) {
1192 case LTTNG_DOMAIN_KERNEL:
1193 if (!is_root) {
1194 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
1195 goto error;
1196 }
1197
1198 /* Kernel tracer check */
1199 if (!kernel_tracer_is_initialized()) {
1200 /* Basically, load kernel tracer modules */
1201 ret = init_kernel_tracer();
1202 if (ret != 0) {
1203 goto error;
1204 }
1205 }
1206
1207 /* Consumer is in an ERROR state. Report back to client */
1208 if (need_consumerd && uatomic_read(&the_kernel_consumerd_state) ==
1209 CONSUMER_ERROR) {
1210 ret = LTTNG_ERR_NO_KERNCONSUMERD;
1211 goto error;
1212 }
1213
1214 /* Need a session for kernel command */
1215 if (need_tracing_session) {
1216 if (cmd_ctx->session->kernel_session == NULL) {
1217 ret = create_kernel_session(cmd_ctx->session);
1218 if (ret != LTTNG_OK) {
1219 ret = LTTNG_ERR_KERN_SESS_FAIL;
1220 goto error;
1221 }
1222 }
1223
1224 /* Start the kernel consumer daemon */
1225 pthread_mutex_lock(&the_kconsumer_data.pid_mutex);
1226 if (the_kconsumer_data.pid == 0 &&
1227 cmd_ctx->lsm.cmd_type != LTTNG_REGISTER_CONSUMER) {
1228 pthread_mutex_unlock(&the_kconsumer_data.pid_mutex);
1229 ret = start_consumerd(&the_kconsumer_data);
1230 if (ret < 0) {
1231 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
1232 goto error;
1233 }
1234 uatomic_set(&the_kernel_consumerd_state, CONSUMER_STARTED);
1235 } else {
1236 pthread_mutex_unlock(&the_kconsumer_data.pid_mutex);
1237 }
1238
1239 /*
1240 * The consumer was just spawned so we need to add the socket to
1241 * the consumer output of the session if exist.
1242 */
1243 ret = consumer_create_socket(&the_kconsumer_data,
1244 cmd_ctx->session->kernel_session->consumer);
1245 if (ret < 0) {
1246 goto error;
1247 }
1248 }
1249
1250 break;
1251 case LTTNG_DOMAIN_JUL:
1252 case LTTNG_DOMAIN_LOG4J:
1253 case LTTNG_DOMAIN_PYTHON:
1254 if (!agent_tracing_is_enabled()) {
1255 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
1256 goto error;
1257 }
1258 /* Fallthrough */
1259 case LTTNG_DOMAIN_UST:
1260 {
1261 if (!ust_app_supported()) {
1262 ret = LTTNG_ERR_NO_UST;
1263 goto error;
1264 }
1265
1266 /* Consumer is in an ERROR state. Report back to client */
1267 if (need_consumerd &&
1268 uatomic_read(&the_ust_consumerd_state) ==
1269 CONSUMER_ERROR) {
1270 ret = LTTNG_ERR_NO_USTCONSUMERD;
1271 goto error;
1272 }
1273
1274 if (need_tracing_session) {
1275 /* Create UST session if none exist. */
1276 if (cmd_ctx->session->ust_session == NULL) {
1277 ret = create_ust_session(cmd_ctx->session,
1278 ALIGNED_CONST_PTR(cmd_ctx->lsm.domain));
1279 if (ret != LTTNG_OK) {
1280 goto error;
1281 }
1282 }
1283
1284 /* Start the UST consumer daemons */
1285 /* 64-bit */
1286 pthread_mutex_lock(&the_ustconsumer64_data.pid_mutex);
1287 if (the_config.consumerd64_bin_path.value &&
1288 the_ustconsumer64_data.pid == 0 &&
1289 cmd_ctx->lsm.cmd_type != LTTNG_REGISTER_CONSUMER) {
1290 pthread_mutex_unlock(&the_ustconsumer64_data.pid_mutex);
1291 ret = start_consumerd(&the_ustconsumer64_data);
1292 if (ret < 0) {
1293 ret = LTTNG_ERR_UST_CONSUMER64_FAIL;
1294 uatomic_set(&the_ust_consumerd64_fd, -EINVAL);
1295 goto error;
1296 }
1297
1298 uatomic_set(&the_ust_consumerd64_fd, the_ustconsumer64_data.cmd_sock);
1299 uatomic_set(&the_ust_consumerd_state, CONSUMER_STARTED);
1300 } else {
1301 pthread_mutex_unlock(&the_ustconsumer64_data.pid_mutex);
1302 }
1303
1304 /*
1305 * Setup socket for consumer 64 bit. No need for atomic access
1306 * since it was set above and can ONLY be set in this thread.
1307 */
1308 ret = consumer_create_socket(&the_ustconsumer64_data,
1309 cmd_ctx->session->ust_session->consumer);
1310 if (ret < 0) {
1311 goto error;
1312 }
1313
1314 /* 32-bit */
1315 pthread_mutex_lock(&the_ustconsumer32_data.pid_mutex);
1316 if (the_config.consumerd32_bin_path.value &&
1317 the_ustconsumer32_data.pid == 0 &&
1318 cmd_ctx->lsm.cmd_type != LTTNG_REGISTER_CONSUMER) {
1319 pthread_mutex_unlock(&the_ustconsumer32_data.pid_mutex);
1320 ret = start_consumerd(&the_ustconsumer32_data);
1321 if (ret < 0) {
1322 ret = LTTNG_ERR_UST_CONSUMER32_FAIL;
1323 uatomic_set(&the_ust_consumerd32_fd, -EINVAL);
1324 goto error;
1325 }
1326
1327 uatomic_set(&the_ust_consumerd32_fd, the_ustconsumer32_data.cmd_sock);
1328 uatomic_set(&the_ust_consumerd_state, CONSUMER_STARTED);
1329 } else {
1330 pthread_mutex_unlock(&the_ustconsumer32_data.pid_mutex);
1331 }
1332
1333 /*
1334 * Setup socket for consumer 32 bit. No need for atomic access
1335 * since it was set above and can ONLY be set in this thread.
1336 */
1337 ret = consumer_create_socket(&the_ustconsumer32_data,
1338 cmd_ctx->session->ust_session->consumer);
1339 if (ret < 0) {
1340 goto error;
1341 }
1342 }
1343 break;
1344 }
1345 default:
1346 break;
1347 }
1348 skip_domain:
1349
1350 /* Validate consumer daemon state when start/stop trace command */
1351 if (cmd_ctx->lsm.cmd_type == LTTNG_START_TRACE ||
1352 cmd_ctx->lsm.cmd_type == LTTNG_STOP_TRACE) {
1353 switch (cmd_ctx->lsm.domain.type) {
1354 case LTTNG_DOMAIN_NONE:
1355 break;
1356 case LTTNG_DOMAIN_JUL:
1357 case LTTNG_DOMAIN_LOG4J:
1358 case LTTNG_DOMAIN_PYTHON:
1359 case LTTNG_DOMAIN_UST:
1360 if (uatomic_read(&the_ust_consumerd_state) != CONSUMER_STARTED) {
1361 ret = LTTNG_ERR_NO_USTCONSUMERD;
1362 goto error;
1363 }
1364 break;
1365 case LTTNG_DOMAIN_KERNEL:
1366 if (uatomic_read(&the_kernel_consumerd_state) != CONSUMER_STARTED) {
1367 ret = LTTNG_ERR_NO_KERNCONSUMERD;
1368 goto error;
1369 }
1370 break;
1371 default:
1372 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1373 goto error;
1374 }
1375 }
1376
1377 /*
1378 * Check that the UID matches that of the tracing session.
1379 * The root user can interact with all sessions.
1380 */
1381 if (need_tracing_session) {
1382 if (!session_access_ok(cmd_ctx->session,
1383 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds)) ||
1384 cmd_ctx->session->destroyed) {
1385 ret = LTTNG_ERR_EPERM;
1386 goto error;
1387 }
1388 }
1389
1390 /*
1391 * Send relayd information to consumer as soon as we have a domain and a
1392 * session defined.
1393 */
1394 if (cmd_ctx->session && need_domain) {
1395 /*
1396 * Setup relayd if not done yet. If the relayd information was already
1397 * sent to the consumer, this call will gracefully return.
1398 */
1399 ret = cmd_setup_relayd(cmd_ctx->session);
1400 if (ret != LTTNG_OK) {
1401 goto error;
1402 }
1403 }
1404
1405 /* Process by command type */
1406 switch (cmd_ctx->lsm.cmd_type) {
1407 case LTTNG_ADD_CONTEXT:
1408 {
1409 struct lttng_event_context *event_context = NULL;
1410 const enum lttng_error_code ret_code =
1411 receive_lttng_event_context(
1412 cmd_ctx, *sock, sock_error, &event_context);
1413
1414 if (ret_code != LTTNG_OK) {
1415 ret = (int) ret_code;
1416 goto error;
1417 }
1418
1419 ret = cmd_add_context(cmd_ctx, event_context, the_kernel_poll_pipe[1]);
1420 lttng_event_context_destroy(event_context);
1421 break;
1422 }
1423 case LTTNG_DISABLE_CHANNEL:
1424 {
1425 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm.domain.type,
1426 cmd_ctx->lsm.u.disable.channel_name);
1427 break;
1428 }
1429 case LTTNG_ENABLE_CHANNEL:
1430 {
1431 ret = cmd_enable_channel(
1432 cmd_ctx, *sock, the_kernel_poll_pipe[1]);
1433 break;
1434 }
1435 case LTTNG_PROCESS_ATTR_TRACKER_ADD_INCLUDE_VALUE:
1436 case LTTNG_PROCESS_ATTR_TRACKER_REMOVE_INCLUDE_VALUE:
1437 {
1438 struct lttng_dynamic_buffer payload;
1439 struct lttng_buffer_view payload_view;
1440 const bool add_value =
1441 cmd_ctx->lsm.cmd_type ==
1442 LTTNG_PROCESS_ATTR_TRACKER_ADD_INCLUDE_VALUE;
1443 const size_t name_len =
1444 cmd_ctx->lsm.u.process_attr_tracker_add_remove_include_value
1445 .name_len;
1446 const enum lttng_domain_type domain_type =
1447 (enum lttng_domain_type)
1448 cmd_ctx->lsm.domain.type;
1449 const enum lttng_process_attr process_attr =
1450 (enum lttng_process_attr) cmd_ctx->lsm.u
1451 .process_attr_tracker_add_remove_include_value
1452 .process_attr;
1453 const enum lttng_process_attr_value_type value_type =
1454 (enum lttng_process_attr_value_type) cmd_ctx
1455 ->lsm.u
1456 .process_attr_tracker_add_remove_include_value
1457 .value_type;
1458 struct process_attr_value *value;
1459 enum lttng_error_code ret_code;
1460 long login_name_max;
1461
1462 login_name_max = sysconf(_SC_LOGIN_NAME_MAX);
1463 if (login_name_max < 0) {
1464 PERROR("Failed to get _SC_LOGIN_NAME_MAX system configuration");
1465 ret = LTTNG_ERR_INVALID;
1466 goto error;
1467 }
1468
1469 /* Receive remaining variable length payload if applicable. */
1470 if (name_len > login_name_max) {
1471 /*
1472 * POSIX mandates user and group names that are at least
1473 * 8 characters long. Note that although shadow-utils
1474 * (useradd, groupaadd, etc.) use 32 chars as their
1475 * limit (from bits/utmp.h, UT_NAMESIZE),
1476 * LOGIN_NAME_MAX is defined to 256.
1477 */
1478 ERR("Rejecting process attribute tracker value %s as the provided exceeds the maximal allowed length: argument length = %zu, maximal length = %ld",
1479 add_value ? "addition" : "removal",
1480 name_len, login_name_max);
1481 ret = LTTNG_ERR_INVALID;
1482 goto error;
1483 }
1484
1485 lttng_dynamic_buffer_init(&payload);
1486 if (name_len != 0) {
1487 /*
1488 * Receive variable payload for user/group name
1489 * arguments.
1490 */
1491 ret = lttng_dynamic_buffer_set_size(&payload, name_len);
1492 if (ret) {
1493 ERR("Failed to allocate buffer to receive payload of %s process attribute tracker value argument",
1494 add_value ? "add" : "remove");
1495 ret = LTTNG_ERR_NOMEM;
1496 goto error_add_remove_tracker_value;
1497 }
1498
1499 ret = lttcomm_recv_unix_sock(
1500 *sock, payload.data, name_len);
1501 if (ret <= 0) {
1502 ERR("Failed to receive payload of %s process attribute tracker value argument",
1503 add_value ? "add" : "remove");
1504 *sock_error = 1;
1505 ret = LTTNG_ERR_INVALID_PROTOCOL;
1506 goto error_add_remove_tracker_value;
1507 }
1508 }
1509
1510 payload_view = lttng_buffer_view_from_dynamic_buffer(
1511 &payload, 0, name_len);
1512 if (name_len > 0 && !lttng_buffer_view_is_valid(&payload_view)) {
1513 ret = LTTNG_ERR_INVALID_PROTOCOL;
1514 goto error_add_remove_tracker_value;
1515 }
1516
1517 /*
1518 * Validate the value type and domains are legal for the process
1519 * attribute tracker that is specified and convert the value to
1520 * add/remove to the internal sessiond representation.
1521 */
1522 ret_code = process_attr_value_from_comm(domain_type,
1523 process_attr, value_type,
1524 &cmd_ctx->lsm.u.process_attr_tracker_add_remove_include_value
1525 .integral_value,
1526 &payload_view, &value);
1527 if (ret_code != LTTNG_OK) {
1528 ret = ret_code;
1529 goto error_add_remove_tracker_value;
1530 }
1531
1532 if (add_value) {
1533 ret = cmd_process_attr_tracker_inclusion_set_add_value(
1534 cmd_ctx->session, domain_type,
1535 process_attr, value);
1536 } else {
1537 ret = cmd_process_attr_tracker_inclusion_set_remove_value(
1538 cmd_ctx->session, domain_type,
1539 process_attr, value);
1540 }
1541 process_attr_value_destroy(value);
1542 error_add_remove_tracker_value:
1543 lttng_dynamic_buffer_reset(&payload);
1544 break;
1545 }
1546 case LTTNG_PROCESS_ATTR_TRACKER_GET_POLICY:
1547 {
1548 enum lttng_tracking_policy tracking_policy;
1549 const enum lttng_domain_type domain_type =
1550 (enum lttng_domain_type)
1551 cmd_ctx->lsm.domain.type;
1552 const enum lttng_process_attr process_attr =
1553 (enum lttng_process_attr) cmd_ctx->lsm.u
1554 .process_attr_tracker_get_tracking_policy
1555 .process_attr;
1556
1557 ret = cmd_process_attr_tracker_get_tracking_policy(
1558 cmd_ctx->session, domain_type, process_attr,
1559 &tracking_policy);
1560 if (ret != LTTNG_OK) {
1561 goto error;
1562 }
1563
1564 ret = setup_lttng_msg_no_cmd_header(cmd_ctx,
1565 &(uint32_t){tracking_policy}, sizeof(uint32_t));
1566 if (ret < 0) {
1567 ret = LTTNG_ERR_NOMEM;
1568 goto error;
1569 }
1570 ret = LTTNG_OK;
1571 break;
1572 }
1573 case LTTNG_PROCESS_ATTR_TRACKER_SET_POLICY:
1574 {
1575 const enum lttng_tracking_policy tracking_policy =
1576 (enum lttng_tracking_policy) cmd_ctx->lsm.u
1577 .process_attr_tracker_set_tracking_policy
1578 .tracking_policy;
1579 const enum lttng_domain_type domain_type =
1580 (enum lttng_domain_type)
1581 cmd_ctx->lsm.domain.type;
1582 const enum lttng_process_attr process_attr =
1583 (enum lttng_process_attr) cmd_ctx->lsm.u
1584 .process_attr_tracker_set_tracking_policy
1585 .process_attr;
1586
1587 ret = cmd_process_attr_tracker_set_tracking_policy(
1588 cmd_ctx->session, domain_type, process_attr,
1589 tracking_policy);
1590 if (ret != LTTNG_OK) {
1591 goto error;
1592 }
1593 break;
1594 }
1595 case LTTNG_PROCESS_ATTR_TRACKER_GET_INCLUSION_SET:
1596 {
1597 struct lttng_process_attr_values *values;
1598 struct lttng_dynamic_buffer reply;
1599 const enum lttng_domain_type domain_type =
1600 (enum lttng_domain_type)
1601 cmd_ctx->lsm.domain.type;
1602 const enum lttng_process_attr process_attr =
1603 (enum lttng_process_attr) cmd_ctx->lsm.u
1604 .process_attr_tracker_get_inclusion_set
1605 .process_attr;
1606
1607 ret = cmd_process_attr_tracker_get_inclusion_set(
1608 cmd_ctx->session, domain_type, process_attr,
1609 &values);
1610 if (ret != LTTNG_OK) {
1611 goto error;
1612 }
1613
1614 lttng_dynamic_buffer_init(&reply);
1615 ret = lttng_process_attr_values_serialize(values, &reply);
1616 if (ret < 0) {
1617 goto error_tracker_get_inclusion_set;
1618 }
1619
1620 ret = setup_lttng_msg_no_cmd_header(
1621 cmd_ctx, reply.data, reply.size);
1622 if (ret < 0) {
1623 ret = LTTNG_ERR_NOMEM;
1624 goto error_tracker_get_inclusion_set;
1625 }
1626 ret = LTTNG_OK;
1627
1628 error_tracker_get_inclusion_set:
1629 lttng_process_attr_values_destroy(values);
1630 lttng_dynamic_buffer_reset(&reply);
1631 break;
1632 }
1633 case LTTNG_ENABLE_EVENT:
1634 case LTTNG_DISABLE_EVENT:
1635 {
1636 struct lttng_event *event;
1637 char *filter_expression;
1638 struct lttng_event_exclusion *exclusions;
1639 struct lttng_bytecode *bytecode;
1640 const enum lttng_error_code ret_code = receive_lttng_event(
1641 cmd_ctx, *sock, sock_error, &event,
1642 &filter_expression, &bytecode, &exclusions);
1643
1644 if (ret_code != LTTNG_OK) {
1645 ret = (int) ret_code;
1646 goto error;
1647 }
1648
1649 /*
1650 * Ownership of filter_expression, exclusions, and bytecode is
1651 * always transferred.
1652 */
1653 ret = cmd_ctx->lsm.cmd_type == LTTNG_ENABLE_EVENT ?
1654 cmd_enable_event(cmd_ctx, event,
1655 filter_expression, exclusions,
1656 bytecode,
1657 the_kernel_poll_pipe[1]) :
1658 cmd_disable_event(cmd_ctx, event,
1659 filter_expression, bytecode,
1660 exclusions);
1661 lttng_event_destroy(event);
1662 break;
1663 }
1664 case LTTNG_LIST_TRACEPOINTS:
1665 {
1666 enum lttng_error_code ret_code;
1667 size_t original_payload_size;
1668 size_t payload_size;
1669 const size_t command_header_size = sizeof(struct lttcomm_list_command_header);
1670
1671 ret = setup_empty_lttng_msg(cmd_ctx);
1672 if (ret) {
1673 ret = LTTNG_ERR_NOMEM;
1674 goto setup_error;
1675 }
1676
1677 original_payload_size = cmd_ctx->reply_payload.buffer.size;
1678
1679 session_lock_list();
1680 ret_code = cmd_list_tracepoints(cmd_ctx->lsm.domain.type,
1681 &cmd_ctx->reply_payload);
1682 session_unlock_list();
1683 if (ret_code != LTTNG_OK) {
1684 ret = (int) ret_code;
1685 goto error;
1686 }
1687
1688 payload_size = cmd_ctx->reply_payload.buffer.size -
1689 command_header_size - original_payload_size;
1690 update_lttng_msg(cmd_ctx, command_header_size, payload_size);
1691
1692 ret = LTTNG_OK;
1693 break;
1694 }
1695 case LTTNG_LIST_TRACEPOINT_FIELDS:
1696 {
1697 enum lttng_error_code ret_code;
1698 size_t original_payload_size;
1699 size_t payload_size;
1700 const size_t command_header_size = sizeof(struct lttcomm_list_command_header);
1701
1702 ret = setup_empty_lttng_msg(cmd_ctx);
1703 if (ret) {
1704 ret = LTTNG_ERR_NOMEM;
1705 goto setup_error;
1706 }
1707
1708 original_payload_size = cmd_ctx->reply_payload.buffer.size;
1709
1710 session_lock_list();
1711 ret_code = cmd_list_tracepoint_fields(
1712 cmd_ctx->lsm.domain.type, &cmd_ctx->reply_payload);
1713 session_unlock_list();
1714 if (ret_code != LTTNG_OK) {
1715 ret = (int) ret_code;
1716 goto error;
1717 }
1718
1719 payload_size = cmd_ctx->reply_payload.buffer.size -
1720 command_header_size - original_payload_size;
1721 update_lttng_msg(cmd_ctx, command_header_size, payload_size);
1722
1723 ret = LTTNG_OK;
1724 break;
1725 }
1726 case LTTNG_LIST_SYSCALLS:
1727 {
1728 enum lttng_error_code ret_code;
1729 size_t original_payload_size;
1730 size_t payload_size;
1731 const size_t command_header_size = sizeof(struct lttcomm_list_command_header);
1732
1733 ret = setup_empty_lttng_msg(cmd_ctx);
1734 if (ret) {
1735 ret = LTTNG_ERR_NOMEM;
1736 goto setup_error;
1737 }
1738
1739 original_payload_size = cmd_ctx->reply_payload.buffer.size;
1740
1741 ret_code = cmd_list_syscalls(&cmd_ctx->reply_payload);
1742 if (ret_code != LTTNG_OK) {
1743 ret = (int) ret_code;
1744 goto error;
1745 }
1746
1747 payload_size = cmd_ctx->reply_payload.buffer.size -
1748 command_header_size - original_payload_size;
1749 update_lttng_msg(cmd_ctx, command_header_size, payload_size);
1750
1751 ret = LTTNG_OK;
1752 break;
1753 }
1754 case LTTNG_SET_CONSUMER_URI:
1755 {
1756 size_t nb_uri, len;
1757 struct lttng_uri *uris;
1758
1759 nb_uri = cmd_ctx->lsm.u.uri.size;
1760 len = nb_uri * sizeof(struct lttng_uri);
1761
1762 if (nb_uri == 0) {
1763 ret = LTTNG_ERR_INVALID;
1764 goto error;
1765 }
1766
1767 uris = zmalloc(len);
1768 if (uris == NULL) {
1769 ret = LTTNG_ERR_FATAL;
1770 goto error;
1771 }
1772
1773 /* Receive variable len data */
1774 DBG("Receiving %zu URI(s) from client ...", nb_uri);
1775 ret = lttcomm_recv_unix_sock(*sock, uris, len);
1776 if (ret <= 0) {
1777 DBG("No URIs received from client... continuing");
1778 *sock_error = 1;
1779 ret = LTTNG_ERR_SESSION_FAIL;
1780 free(uris);
1781 goto error;
1782 }
1783
1784 ret = cmd_set_consumer_uri(cmd_ctx->session, nb_uri, uris);
1785 free(uris);
1786 if (ret != LTTNG_OK) {
1787 goto error;
1788 }
1789
1790
1791 break;
1792 }
1793 case LTTNG_START_TRACE:
1794 {
1795 /*
1796 * On the first start, if we have a kernel session and we have
1797 * enabled time or size-based rotations, we have to make sure
1798 * the kernel tracer supports it.
1799 */
1800 if (!cmd_ctx->session->has_been_started && \
1801 cmd_ctx->session->kernel_session && \
1802 (cmd_ctx->session->rotate_timer_period || \
1803 cmd_ctx->session->rotate_size) && \
1804 !check_rotate_compatible()) {
1805 DBG("Kernel tracer version is not compatible with the rotation feature");
1806 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
1807 goto error;
1808 }
1809 ret = cmd_start_trace(cmd_ctx->session);
1810 break;
1811 }
1812 case LTTNG_STOP_TRACE:
1813 {
1814 ret = cmd_stop_trace(cmd_ctx->session);
1815 break;
1816 }
1817 case LTTNG_DESTROY_SESSION:
1818 {
1819 ret = cmd_destroy_session(cmd_ctx->session,
1820 the_notification_thread_handle, sock);
1821 break;
1822 }
1823 case LTTNG_LIST_DOMAINS:
1824 {
1825 ssize_t nb_dom;
1826 struct lttng_domain *domains = NULL;
1827
1828 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
1829 if (nb_dom < 0) {
1830 /* Return value is a negative lttng_error_code. */
1831 ret = -nb_dom;
1832 goto error;
1833 }
1834
1835 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, domains,
1836 nb_dom * sizeof(struct lttng_domain));
1837 free(domains);
1838
1839 if (ret < 0) {
1840 goto setup_error;
1841 }
1842
1843 ret = LTTNG_OK;
1844 break;
1845 }
1846 case LTTNG_LIST_CHANNELS:
1847 {
1848 enum lttng_error_code ret_code;
1849 size_t original_payload_size;
1850 size_t payload_size;
1851 const size_t command_header_size = sizeof(struct lttcomm_list_command_header);
1852
1853 ret = setup_empty_lttng_msg(cmd_ctx);
1854 if (ret) {
1855 ret = LTTNG_ERR_NOMEM;
1856 goto setup_error;
1857 }
1858
1859 original_payload_size = cmd_ctx->reply_payload.buffer.size;
1860
1861 ret_code = cmd_list_channels(cmd_ctx->lsm.domain.type,
1862 cmd_ctx->session, &cmd_ctx->reply_payload);
1863 if (ret_code != LTTNG_OK) {
1864 ret = (int) ret_code;
1865 goto error;
1866 }
1867
1868 payload_size = cmd_ctx->reply_payload.buffer.size -
1869 command_header_size - original_payload_size;
1870 update_lttng_msg(cmd_ctx, command_header_size, payload_size);
1871
1872 ret = LTTNG_OK;
1873 break;
1874 }
1875 case LTTNG_LIST_EVENTS:
1876 {
1877 enum lttng_error_code ret_code;
1878 size_t original_payload_size;
1879 size_t payload_size;
1880 const size_t command_header_size = sizeof(struct lttcomm_list_command_header);
1881
1882 ret = setup_empty_lttng_msg(cmd_ctx);
1883 if (ret) {
1884 ret = LTTNG_ERR_NOMEM;
1885 goto setup_error;
1886 }
1887
1888 original_payload_size = cmd_ctx->reply_payload.buffer.size;
1889
1890 ret_code = cmd_list_events(cmd_ctx->lsm.domain.type,
1891 cmd_ctx->session,
1892 cmd_ctx->lsm.u.list.channel_name, &cmd_ctx->reply_payload);
1893 if (ret_code != LTTNG_OK) {
1894 ret = (int) ret_code;
1895 goto error;
1896 }
1897
1898 payload_size = cmd_ctx->reply_payload.buffer.size -
1899 command_header_size - original_payload_size;
1900 update_lttng_msg(cmd_ctx, command_header_size, payload_size);
1901
1902 ret = LTTNG_OK;
1903 break;
1904 }
1905 case LTTNG_LIST_SESSIONS:
1906 {
1907 unsigned int nr_sessions;
1908 void *sessions_payload;
1909 size_t payload_len;
1910
1911 session_lock_list();
1912 nr_sessions = lttng_sessions_count(
1913 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1914 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
1915
1916 payload_len = (sizeof(struct lttng_session) * nr_sessions) +
1917 (sizeof(struct lttng_session_extended) * nr_sessions);
1918 sessions_payload = zmalloc(payload_len);
1919
1920 if (!sessions_payload) {
1921 session_unlock_list();
1922 ret = -ENOMEM;
1923 goto setup_error;
1924 }
1925
1926 cmd_list_lttng_sessions(sessions_payload, nr_sessions,
1927 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1928 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
1929 session_unlock_list();
1930
1931 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, sessions_payload,
1932 payload_len);
1933 free(sessions_payload);
1934
1935 if (ret < 0) {
1936 goto setup_error;
1937 }
1938
1939 ret = LTTNG_OK;
1940 break;
1941 }
1942 case LTTNG_REGISTER_CONSUMER:
1943 {
1944 struct consumer_data *cdata;
1945
1946 switch (cmd_ctx->lsm.domain.type) {
1947 case LTTNG_DOMAIN_KERNEL:
1948 cdata = &the_kconsumer_data;
1949 break;
1950 default:
1951 ret = LTTNG_ERR_UND;
1952 goto error;
1953 }
1954
1955 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm.domain.type,
1956 cmd_ctx->lsm.u.reg.path, cdata);
1957 break;
1958 }
1959 case LTTNG_DATA_PENDING:
1960 {
1961 int pending_ret;
1962 uint8_t pending_ret_byte;
1963
1964 pending_ret = cmd_data_pending(cmd_ctx->session);
1965
1966 /*
1967 * FIXME
1968 *
1969 * This function may returns 0 or 1 to indicate whether or not
1970 * there is data pending. In case of error, it should return an
1971 * LTTNG_ERR code. However, some code paths may still return
1972 * a nondescript error code, which we handle by returning an
1973 * "unknown" error.
1974 */
1975 if (pending_ret == 0 || pending_ret == 1) {
1976 /*
1977 * ret will be set to LTTNG_OK at the end of
1978 * this function.
1979 */
1980 } else if (pending_ret < 0) {
1981 ret = LTTNG_ERR_UNK;
1982 goto setup_error;
1983 } else {
1984 ret = pending_ret;
1985 goto setup_error;
1986 }
1987
1988 pending_ret_byte = (uint8_t) pending_ret;
1989
1990 /* 1 byte to return whether or not data is pending */
1991 ret = setup_lttng_msg_no_cmd_header(cmd_ctx,
1992 &pending_ret_byte, 1);
1993
1994 if (ret < 0) {
1995 goto setup_error;
1996 }
1997
1998 ret = LTTNG_OK;
1999 break;
2000 }
2001 case LTTNG_SNAPSHOT_ADD_OUTPUT:
2002 {
2003 uint32_t snapshot_id;
2004 struct lttcomm_lttng_output_id reply;
2005
2006 ret = cmd_snapshot_add_output(cmd_ctx->session,
2007 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.snapshot_output.output),
2008 &snapshot_id);
2009 if (ret != LTTNG_OK) {
2010 goto error;
2011 }
2012 reply.id = snapshot_id;
2013
2014 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &reply,
2015 sizeof(reply));
2016 if (ret < 0) {
2017 goto setup_error;
2018 }
2019
2020 /* Copy output list into message payload */
2021 ret = LTTNG_OK;
2022 break;
2023 }
2024 case LTTNG_SNAPSHOT_DEL_OUTPUT:
2025 {
2026 ret = cmd_snapshot_del_output(cmd_ctx->session,
2027 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.snapshot_output.output));
2028 break;
2029 }
2030 case LTTNG_SNAPSHOT_LIST_OUTPUT:
2031 {
2032 ssize_t nb_output;
2033 struct lttng_snapshot_output *outputs = NULL;
2034
2035 nb_output = cmd_snapshot_list_outputs(cmd_ctx->session, &outputs);
2036 if (nb_output < 0) {
2037 ret = -nb_output;
2038 goto error;
2039 }
2040
2041 assert((nb_output > 0 && outputs) || nb_output == 0);
2042 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, outputs,
2043 nb_output * sizeof(struct lttng_snapshot_output));
2044 free(outputs);
2045
2046 if (ret < 0) {
2047 goto setup_error;
2048 }
2049
2050 ret = LTTNG_OK;
2051 break;
2052 }
2053 case LTTNG_SNAPSHOT_RECORD:
2054 {
2055 ret = cmd_snapshot_record(cmd_ctx->session,
2056 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.snapshot_record.output),
2057 cmd_ctx->lsm.u.snapshot_record.wait);
2058 break;
2059 }
2060 case LTTNG_CREATE_SESSION_EXT:
2061 {
2062 struct lttng_dynamic_buffer payload;
2063 struct lttng_session_descriptor *return_descriptor = NULL;
2064
2065 lttng_dynamic_buffer_init(&payload);
2066 ret = cmd_create_session(cmd_ctx, *sock, &return_descriptor);
2067 if (ret != LTTNG_OK) {
2068 goto error;
2069 }
2070
2071 ret = lttng_session_descriptor_serialize(return_descriptor,
2072 &payload);
2073 if (ret) {
2074 ERR("Failed to serialize session descriptor in reply to \"create session\" command");
2075 lttng_session_descriptor_destroy(return_descriptor);
2076 ret = LTTNG_ERR_NOMEM;
2077 goto error;
2078 }
2079 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, payload.data,
2080 payload.size);
2081 if (ret) {
2082 lttng_session_descriptor_destroy(return_descriptor);
2083 ret = LTTNG_ERR_NOMEM;
2084 goto error;
2085 }
2086 lttng_dynamic_buffer_reset(&payload);
2087 lttng_session_descriptor_destroy(return_descriptor);
2088 ret = LTTNG_OK;
2089 break;
2090 }
2091 case LTTNG_SAVE_SESSION:
2092 {
2093 ret = cmd_save_sessions(&cmd_ctx->lsm.u.save_session.attr,
2094 &cmd_ctx->creds);
2095 break;
2096 }
2097 case LTTNG_SET_SESSION_SHM_PATH:
2098 {
2099 ret = cmd_set_session_shm_path(cmd_ctx->session,
2100 cmd_ctx->lsm.u.set_shm_path.shm_path);
2101 break;
2102 }
2103 case LTTNG_REGENERATE_METADATA:
2104 {
2105 ret = cmd_regenerate_metadata(cmd_ctx->session);
2106 break;
2107 }
2108 case LTTNG_REGENERATE_STATEDUMP:
2109 {
2110 ret = cmd_regenerate_statedump(cmd_ctx->session);
2111 break;
2112 }
2113 case LTTNG_REGISTER_TRIGGER:
2114 {
2115 struct lttng_trigger *payload_trigger;
2116 struct lttng_trigger *return_trigger;
2117 size_t original_reply_payload_size;
2118 size_t reply_payload_size;
2119 const struct lttng_credentials cmd_creds = {
2120 .uid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.uid),
2121 .gid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.gid),
2122 };
2123
2124 ret = setup_empty_lttng_msg(cmd_ctx);
2125 if (ret) {
2126 ret = LTTNG_ERR_NOMEM;
2127 goto setup_error;
2128 }
2129
2130 ret = receive_lttng_trigger(
2131 cmd_ctx, *sock, sock_error, &payload_trigger);
2132 if (ret != LTTNG_OK) {
2133 goto error;
2134 }
2135
2136 original_reply_payload_size = cmd_ctx->reply_payload.buffer.size;
2137
2138 ret = cmd_register_trigger(&cmd_creds, payload_trigger,
2139 cmd_ctx->lsm.u.trigger.is_trigger_anonymous,
2140 the_notification_thread_handle,
2141 &return_trigger);
2142 if (ret != LTTNG_OK) {
2143 lttng_trigger_put(payload_trigger);
2144 goto error;
2145 }
2146
2147 ret = lttng_trigger_serialize(return_trigger, &cmd_ctx->reply_payload);
2148 lttng_trigger_put(payload_trigger);
2149 lttng_trigger_put(return_trigger);
2150 if (ret) {
2151 ERR("Failed to serialize trigger in reply to \"register trigger\" command");
2152 ret = LTTNG_ERR_NOMEM;
2153 goto error;
2154 }
2155
2156 reply_payload_size = cmd_ctx->reply_payload.buffer.size -
2157 original_reply_payload_size;
2158
2159 update_lttng_msg(cmd_ctx, 0, reply_payload_size);
2160
2161 ret = LTTNG_OK;
2162 break;
2163 }
2164 case LTTNG_UNREGISTER_TRIGGER:
2165 {
2166 struct lttng_trigger *payload_trigger;
2167 const struct lttng_credentials cmd_creds = {
2168 .uid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.uid),
2169 .gid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.gid),
2170 };
2171
2172 ret = receive_lttng_trigger(
2173 cmd_ctx, *sock, sock_error, &payload_trigger);
2174 if (ret != LTTNG_OK) {
2175 goto error;
2176 }
2177
2178 ret = cmd_unregister_trigger(&cmd_creds, payload_trigger,
2179 the_notification_thread_handle);
2180 lttng_trigger_put(payload_trigger);
2181 break;
2182 }
2183 case LTTNG_ROTATE_SESSION:
2184 {
2185 struct lttng_rotate_session_return rotate_return;
2186
2187 DBG("Client rotate session \"%s\"", cmd_ctx->session->name);
2188
2189 memset(&rotate_return, 0, sizeof(rotate_return));
2190 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
2191 DBG("Kernel tracer version is not compatible with the rotation feature");
2192 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
2193 goto error;
2194 }
2195
2196 ret = cmd_rotate_session(cmd_ctx->session, &rotate_return,
2197 false,
2198 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
2199 if (ret < 0) {
2200 ret = -ret;
2201 goto error;
2202 }
2203
2204 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &rotate_return,
2205 sizeof(rotate_return));
2206 if (ret < 0) {
2207 ret = -ret;
2208 goto error;
2209 }
2210
2211 ret = LTTNG_OK;
2212 break;
2213 }
2214 case LTTNG_ROTATION_GET_INFO:
2215 {
2216 struct lttng_rotation_get_info_return get_info_return;
2217
2218 memset(&get_info_return, 0, sizeof(get_info_return));
2219 ret = cmd_rotate_get_info(cmd_ctx->session, &get_info_return,
2220 cmd_ctx->lsm.u.get_rotation_info.rotation_id);
2221 if (ret < 0) {
2222 ret = -ret;
2223 goto error;
2224 }
2225
2226 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &get_info_return,
2227 sizeof(get_info_return));
2228 if (ret < 0) {
2229 ret = -ret;
2230 goto error;
2231 }
2232
2233 ret = LTTNG_OK;
2234 break;
2235 }
2236 case LTTNG_ROTATION_SET_SCHEDULE:
2237 {
2238 bool set_schedule;
2239 enum lttng_rotation_schedule_type schedule_type;
2240 uint64_t value;
2241
2242 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
2243 DBG("Kernel tracer version does not support session rotations");
2244 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
2245 goto error;
2246 }
2247
2248 set_schedule = cmd_ctx->lsm.u.rotation_set_schedule.set == 1;
2249 schedule_type = (enum lttng_rotation_schedule_type) cmd_ctx->lsm.u.rotation_set_schedule.type;
2250 value = cmd_ctx->lsm.u.rotation_set_schedule.value;
2251
2252 ret = cmd_rotation_set_schedule(cmd_ctx->session, set_schedule,
2253 schedule_type, value,
2254 the_notification_thread_handle);
2255 if (ret != LTTNG_OK) {
2256 goto error;
2257 }
2258
2259 break;
2260 }
2261 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
2262 {
2263 struct lttng_session_list_schedules_return schedules = {
2264 .periodic.set = !!cmd_ctx->session->rotate_timer_period,
2265 .periodic.value = cmd_ctx->session->rotate_timer_period,
2266 .size.set = !!cmd_ctx->session->rotate_size,
2267 .size.value = cmd_ctx->session->rotate_size,
2268 };
2269
2270 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &schedules,
2271 sizeof(schedules));
2272 if (ret < 0) {
2273 ret = -ret;
2274 goto error;
2275 }
2276
2277 ret = LTTNG_OK;
2278 break;
2279 }
2280 case LTTNG_CLEAR_SESSION:
2281 {
2282 ret = cmd_clear_session(cmd_ctx->session, sock);
2283 break;
2284 }
2285 case LTTNG_LIST_TRIGGERS:
2286 {
2287 struct lttng_triggers *return_triggers = NULL;
2288 size_t original_payload_size;
2289 size_t payload_size;
2290
2291 ret = setup_empty_lttng_msg(cmd_ctx);
2292 if (ret) {
2293 ret = LTTNG_ERR_NOMEM;
2294 goto setup_error;
2295 }
2296
2297 original_payload_size = cmd_ctx->reply_payload.buffer.size;
2298
2299 ret = cmd_list_triggers(cmd_ctx, the_notification_thread_handle,
2300 &return_triggers);
2301 if (ret != LTTNG_OK) {
2302 goto error;
2303 }
2304
2305 assert(return_triggers);
2306 ret = lttng_triggers_serialize(
2307 return_triggers, &cmd_ctx->reply_payload);
2308 lttng_triggers_destroy(return_triggers);
2309 if (ret) {
2310 ERR("Failed to serialize triggers in reply to `list triggers` command");
2311 ret = LTTNG_ERR_NOMEM;
2312 goto error;
2313 }
2314
2315 payload_size = cmd_ctx->reply_payload.buffer.size -
2316 original_payload_size;
2317
2318 update_lttng_msg(cmd_ctx, 0, payload_size);
2319
2320 ret = LTTNG_OK;
2321 break;
2322 }
2323 case LTTNG_EXECUTE_ERROR_QUERY:
2324 {
2325 struct lttng_error_query *query;
2326 const struct lttng_credentials cmd_creds = {
2327 .uid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.uid),
2328 .gid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.gid),
2329 };
2330 struct lttng_error_query_results *results = NULL;
2331 size_t original_payload_size;
2332 size_t payload_size;
2333
2334 ret = setup_empty_lttng_msg(cmd_ctx);
2335 if (ret) {
2336 ret = LTTNG_ERR_NOMEM;
2337 goto setup_error;
2338 }
2339
2340 original_payload_size = cmd_ctx->reply_payload.buffer.size;
2341
2342 ret = receive_lttng_error_query(
2343 cmd_ctx, *sock, sock_error, &query);
2344 if (ret != LTTNG_OK) {
2345 goto error;
2346 }
2347
2348 ret = cmd_execute_error_query(&cmd_creds, query, &results,
2349 the_notification_thread_handle);
2350 lttng_error_query_destroy(query);
2351 if (ret != LTTNG_OK) {
2352 goto error;
2353 }
2354
2355 assert(results);
2356 ret = lttng_error_query_results_serialize(
2357 results, &cmd_ctx->reply_payload);
2358 lttng_error_query_results_destroy(results);
2359 if (ret) {
2360 ERR("Failed to serialize error query result set in reply to `execute error query` command");
2361 ret = LTTNG_ERR_NOMEM;
2362 goto error;
2363 }
2364
2365 payload_size = cmd_ctx->reply_payload.buffer.size -
2366 original_payload_size;
2367
2368 update_lttng_msg(cmd_ctx, 0, payload_size);
2369
2370 ret = LTTNG_OK;
2371
2372 break;
2373 }
2374 default:
2375 ret = LTTNG_ERR_UND;
2376 break;
2377 }
2378
2379 error:
2380 if (cmd_ctx->reply_payload.buffer.size == 0) {
2381 DBG("Missing llm header, creating one.");
2382 if (setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0) < 0) {
2383 goto setup_error;
2384 }
2385 }
2386 /* Set return code */
2387 ((struct lttcomm_lttng_msg *) (cmd_ctx->reply_payload.buffer.data))->ret_code = ret;
2388 setup_error:
2389 if (cmd_ctx->session) {
2390 session_unlock(cmd_ctx->session);
2391 session_put(cmd_ctx->session);
2392 cmd_ctx->session = NULL;
2393 }
2394 if (need_tracing_session) {
2395 session_unlock_list();
2396 }
2397 init_setup_error:
2398 assert(!rcu_read_ongoing());
2399 return ret;
2400 }
2401
2402 static int create_client_sock(void)
2403 {
2404 int ret, client_sock;
2405
2406 /* Create client tool unix socket */
2407 client_sock = lttcomm_create_unix_sock(
2408 the_config.client_unix_sock_path.value);
2409 if (client_sock < 0) {
2410 ERR("Create unix sock failed: %s",
2411 the_config.client_unix_sock_path.value);
2412 ret = -1;
2413 goto end;
2414 }
2415
2416 /* Set the cloexec flag */
2417 ret = utils_set_fd_cloexec(client_sock);
2418 if (ret < 0) {
2419 ERR("Unable to set CLOEXEC flag to the client Unix socket (fd: %d). "
2420 "Continuing but note that the consumer daemon will have a "
2421 "reference to this socket on exec()", client_sock);
2422 }
2423
2424 /* File permission MUST be 660 */
2425 ret = chmod(the_config.client_unix_sock_path.value,
2426 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
2427 if (ret < 0) {
2428 ERR("Set file permissions failed: %s",
2429 the_config.client_unix_sock_path.value);
2430 PERROR("chmod");
2431 (void) lttcomm_close_unix_sock(client_sock);
2432 ret = -1;
2433 goto end;
2434 }
2435 DBG("Created client socket (fd = %i)", client_sock);
2436 ret = client_sock;
2437 end:
2438 return ret;
2439 }
2440
2441 static void cleanup_client_thread(void *data)
2442 {
2443 struct lttng_pipe *quit_pipe = data;
2444
2445 lttng_pipe_destroy(quit_pipe);
2446 }
2447
2448 static void thread_init_cleanup(void *data)
2449 {
2450 set_thread_status(false);
2451 }
2452
2453 /*
2454 * This thread manage all clients request using the unix client socket for
2455 * communication.
2456 */
2457 static void *thread_manage_clients(void *data)
2458 {
2459 int sock = -1, ret, i, pollfd, err = -1;
2460 int sock_error;
2461 uint32_t revents, nb_fd;
2462 struct lttng_poll_event events;
2463 const int client_sock = thread_state.client_sock;
2464 struct lttng_pipe *quit_pipe = data;
2465 const int thread_quit_pipe_fd = lttng_pipe_get_readfd(quit_pipe);
2466 struct command_ctx cmd_ctx = {};
2467
2468 DBG("[thread] Manage client started");
2469
2470 lttng_payload_init(&cmd_ctx.reply_payload);
2471
2472 is_root = (getuid() == 0);
2473
2474 pthread_cleanup_push(thread_init_cleanup, NULL);
2475
2476 rcu_register_thread();
2477
2478 health_register(the_health_sessiond, HEALTH_SESSIOND_TYPE_CMD);
2479
2480 health_code_update();
2481
2482 ret = lttcomm_listen_unix_sock(client_sock);
2483 if (ret < 0) {
2484 goto error_listen;
2485 }
2486
2487 /*
2488 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2489 * more will be added to this poll set.
2490 */
2491 ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
2492 if (ret < 0) {
2493 goto error_create_poll;
2494 }
2495
2496 /* Add the application registration socket */
2497 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
2498 if (ret < 0) {
2499 goto error;
2500 }
2501
2502 /* Add thread quit pipe */
2503 ret = lttng_poll_add(&events, thread_quit_pipe_fd, LPOLLIN | LPOLLERR);
2504 if (ret < 0) {
2505 goto error;
2506 }
2507
2508 /* Set state as running. */
2509 set_thread_status(true);
2510 pthread_cleanup_pop(0);
2511
2512 /* This testpoint is after we signal readiness to the parent. */
2513 if (testpoint(sessiond_thread_manage_clients)) {
2514 goto error;
2515 }
2516
2517 if (testpoint(sessiond_thread_manage_clients_before_loop)) {
2518 goto error;
2519 }
2520
2521 health_code_update();
2522
2523 while (1) {
2524 const struct cmd_completion_handler *cmd_completion_handler;
2525
2526 cmd_ctx.creds = (lttng_sock_cred) {
2527 .uid = UINT32_MAX,
2528 .gid = UINT32_MAX,
2529 };
2530 cmd_ctx.session = NULL;
2531 lttng_payload_clear(&cmd_ctx.reply_payload);
2532 cmd_ctx.lttng_msg_size = 0;
2533
2534 DBG("Accepting client command ...");
2535
2536 /* Inifinite blocking call, waiting for transmission */
2537 restart:
2538 health_poll_entry();
2539 ret = lttng_poll_wait(&events, -1);
2540 health_poll_exit();
2541 if (ret < 0) {
2542 /*
2543 * Restart interrupted system call.
2544 */
2545 if (errno == EINTR) {
2546 goto restart;
2547 }
2548 goto error;
2549 }
2550
2551 nb_fd = ret;
2552
2553 for (i = 0; i < nb_fd; i++) {
2554 revents = LTTNG_POLL_GETEV(&events, i);
2555 pollfd = LTTNG_POLL_GETFD(&events, i);
2556
2557 health_code_update();
2558
2559 if (pollfd == thread_quit_pipe_fd) {
2560 err = 0;
2561 goto exit;
2562 } else {
2563 /* Event on the registration socket */
2564 if (revents & LPOLLIN) {
2565 continue;
2566 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2567 ERR("Client socket poll error");
2568 goto error;
2569 } else {
2570 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
2571 goto error;
2572 }
2573 }
2574 }
2575
2576 DBG("Wait for client response");
2577
2578 health_code_update();
2579
2580 sock = lttcomm_accept_unix_sock(client_sock);
2581 if (sock < 0) {
2582 goto error;
2583 }
2584
2585 /*
2586 * Set the CLOEXEC flag. Return code is useless because either way, the
2587 * show must go on.
2588 */
2589 (void) utils_set_fd_cloexec(sock);
2590
2591 /* Set socket option for credentials retrieval */
2592 ret = lttcomm_setsockopt_creds_unix_sock(sock);
2593 if (ret < 0) {
2594 goto error;
2595 }
2596
2597 health_code_update();
2598
2599 /*
2600 * Data is received from the lttng client. The struct
2601 * lttcomm_session_msg (lsm) contains the command and data request of
2602 * the client.
2603 */
2604 DBG("Receiving data from client ...");
2605 ret = lttcomm_recv_creds_unix_sock(sock, &cmd_ctx.lsm,
2606 sizeof(struct lttcomm_session_msg), &cmd_ctx.creds);
2607 if (ret != sizeof(struct lttcomm_session_msg)) {
2608 DBG("Incomplete recv() from client... continuing");
2609 ret = close(sock);
2610 if (ret) {
2611 PERROR("close");
2612 }
2613 sock = -1;
2614 continue;
2615 }
2616
2617 health_code_update();
2618
2619 // TODO: Validate cmd_ctx including sanity check for
2620 // security purpose.
2621
2622 rcu_thread_online();
2623 /*
2624 * This function dispatch the work to the kernel or userspace tracer
2625 * libs and fill the lttcomm_lttng_msg data structure of all the needed
2626 * informations for the client. The command context struct contains
2627 * everything this function may needs.
2628 */
2629 ret = process_client_msg(&cmd_ctx, &sock, &sock_error);
2630 rcu_thread_offline();
2631 if (ret < 0) {
2632 if (sock >= 0) {
2633 ret = close(sock);
2634 if (ret) {
2635 PERROR("close");
2636 }
2637 }
2638 sock = -1;
2639 /*
2640 * TODO: Inform client somehow of the fatal error. At
2641 * this point, ret < 0 means that a zmalloc failed
2642 * (ENOMEM). Error detected but still accept
2643 * command, unless a socket error has been
2644 * detected.
2645 */
2646 continue;
2647 }
2648
2649 if (ret < LTTNG_OK || ret >= LTTNG_ERR_NR) {
2650 WARN("Command returned an invalid status code, returning unknown error: "
2651 "command type = %s (%d), ret = %d",
2652 lttcomm_sessiond_command_str(cmd_ctx.lsm.cmd_type),
2653 cmd_ctx.lsm.cmd_type, ret);
2654 ret = LTTNG_ERR_UNK;
2655 }
2656
2657 cmd_completion_handler = cmd_pop_completion_handler();
2658 if (cmd_completion_handler) {
2659 enum lttng_error_code completion_code;
2660
2661 completion_code = cmd_completion_handler->run(
2662 cmd_completion_handler->data);
2663 if (completion_code != LTTNG_OK) {
2664 continue;
2665 }
2666 }
2667
2668 health_code_update();
2669
2670 if (sock >= 0) {
2671 struct lttng_payload_view view =
2672 lttng_payload_view_from_payload(
2673 &cmd_ctx.reply_payload,
2674 0, -1);
2675 struct lttcomm_lttng_msg *llm = (typeof(
2676 llm)) cmd_ctx.reply_payload.buffer.data;
2677
2678 assert(cmd_ctx.reply_payload.buffer.size >= sizeof(*llm));
2679 assert(cmd_ctx.lttng_msg_size == cmd_ctx.reply_payload.buffer.size);
2680
2681 llm->fd_count = lttng_payload_view_get_fd_handle_count(&view);
2682
2683 DBG("Sending response (size: %d, retcode: %s (%d))",
2684 cmd_ctx.lttng_msg_size,
2685 lttng_strerror(-llm->ret_code),
2686 llm->ret_code);
2687 ret = send_unix_sock(sock, &view);
2688 if (ret < 0) {
2689 ERR("Failed to send data back to client");
2690 }
2691
2692 /* End of transmission */
2693 ret = close(sock);
2694 if (ret) {
2695 PERROR("close");
2696 }
2697 }
2698 sock = -1;
2699
2700 health_code_update();
2701 }
2702
2703 exit:
2704 error:
2705 if (sock >= 0) {
2706 ret = close(sock);
2707 if (ret) {
2708 PERROR("close");
2709 }
2710 }
2711
2712 lttng_poll_clean(&events);
2713
2714 error_listen:
2715 error_create_poll:
2716 unlink(the_config.client_unix_sock_path.value);
2717 ret = close(client_sock);
2718 if (ret) {
2719 PERROR("close");
2720 }
2721
2722 if (err) {
2723 health_error();
2724 ERR("Health error occurred in %s", __func__);
2725 }
2726
2727 health_unregister(the_health_sessiond);
2728
2729 DBG("Client thread dying");
2730 lttng_payload_reset(&cmd_ctx.reply_payload);
2731 rcu_unregister_thread();
2732 return NULL;
2733 }
2734
2735 static
2736 bool shutdown_client_thread(void *thread_data)
2737 {
2738 struct lttng_pipe *client_quit_pipe = thread_data;
2739 const int write_fd = lttng_pipe_get_writefd(client_quit_pipe);
2740
2741 return notify_thread_pipe(write_fd) == 1;
2742 }
2743
2744 struct lttng_thread *launch_client_thread(void)
2745 {
2746 bool thread_running;
2747 struct lttng_pipe *client_quit_pipe;
2748 struct lttng_thread *thread = NULL;
2749 int client_sock_fd = -1;
2750
2751 sem_init(&thread_state.ready, 0, 0);
2752 client_quit_pipe = lttng_pipe_open(FD_CLOEXEC);
2753 if (!client_quit_pipe) {
2754 goto error;
2755 }
2756
2757 client_sock_fd = create_client_sock();
2758 if (client_sock_fd < 0) {
2759 goto error;
2760 }
2761
2762 thread_state.client_sock = client_sock_fd;
2763 thread = lttng_thread_create("Client management",
2764 thread_manage_clients,
2765 shutdown_client_thread,
2766 cleanup_client_thread,
2767 client_quit_pipe);
2768 if (!thread) {
2769 goto error;
2770 }
2771 /* The client thread now owns the client sock fd and the quit pipe. */
2772 client_sock_fd = -1;
2773 client_quit_pipe = NULL;
2774
2775 /*
2776 * This thread is part of the threads that need to be fully
2777 * initialized before the session daemon is marked as "ready".
2778 */
2779 thread_running = wait_thread_status();
2780 if (!thread_running) {
2781 goto error;
2782 }
2783 return thread;
2784 error:
2785 if (client_sock_fd >= 0) {
2786 if (close(client_sock_fd)) {
2787 PERROR("Failed to close client socket");
2788 }
2789 }
2790 lttng_thread_put(thread);
2791 cleanup_client_thread(client_quit_pipe);
2792 return NULL;
2793 }
LTTng 2.0 tools and control repository
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