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common: move lttng_payload[_view] to libcommon
[lttng-tools.git] / src / bin / lttng-sessiond / client.c
1 /*
2 * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
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-buffer.h"
13 #include "common/dynamic-array.h"
14 #include "common/payload.h"
15 #include "common/payload-view.h"
16 #include "common/sessiond-comm/sessiond-comm.h"
17 #include "lttng/lttng-error.h"
18 #include "lttng/tracker.h"
19 #include <common/compat/getenv.h>
20 #include <common/tracker.h>
21 #include <common/unix.h>
22 #include <common/utils.h>
23 #include <lttng/event-internal.h>
24 #include <lttng/session-descriptor-internal.h>
25 #include <lttng/session-internal.h>
26 #include <lttng/userspace-probe-internal.h>
27 #include <pthread.h>
28 #include <signal.h>
29 #include <stddef.h>
30 #include <sys/stat.h>
31
32 #include "client.h"
33 #include "lttng-sessiond.h"
34 #include "cmd.h"
35 #include "kernel.h"
36 #include "save.h"
37 #include "health-sessiond.h"
38 #include "testpoint.h"
39 #include "utils.h"
40 #include "manage-consumer.h"
41 #include "clear.h"
42
43 static bool is_root;
44
45 static struct thread_state {
46 sem_t ready;
47 bool running;
48 int client_sock;
49 } thread_state;
50
51 static void set_thread_status(bool running)
52 {
53 DBG("Marking client thread's state as %s", running ? "running" : "error");
54 thread_state.running = running;
55 sem_post(&thread_state.ready);
56 }
57
58 static bool wait_thread_status(void)
59 {
60 DBG("Waiting for client thread to be ready");
61 sem_wait(&thread_state.ready);
62 if (thread_state.running) {
63 DBG("Client thread is ready");
64 } else {
65 ERR("Initialization of client thread failed");
66 }
67
68 return thread_state.running;
69 }
70
71 /*
72 * Setup the outgoing data buffer for the response (llm) by allocating the
73 * right amount of memory and copying the original information from the lsm
74 * structure.
75 *
76 * Return 0 on success, negative value on error.
77 */
78 static int setup_lttng_msg(struct command_ctx *cmd_ctx,
79 const void *payload_buf, size_t payload_len,
80 const void *cmd_header_buf, size_t cmd_header_len)
81 {
82 int ret = 0;
83 const size_t header_len = sizeof(struct lttcomm_lttng_msg);
84 const size_t total_msg_size = header_len + cmd_header_len + payload_len;
85 const struct lttcomm_lttng_msg llm = {
86 .cmd_type = cmd_ctx->lsm.cmd_type,
87 .pid = cmd_ctx->lsm.domain.attr.pid,
88 .cmd_header_size = cmd_header_len,
89 .data_size = payload_len,
90 };
91
92 lttng_dynamic_buffer_set_size(&cmd_ctx->reply_payload.buffer, 0);
93
94 cmd_ctx->lttng_msg_size = total_msg_size;
95
96 /* Append reply header. */
97 ret = lttng_dynamic_buffer_append(
98 &cmd_ctx->reply_payload.buffer, &llm, sizeof(llm));
99 if (ret) {
100 goto end;
101 }
102
103 /* Append command header. */
104 if (cmd_header_len) {
105 ret = lttng_dynamic_buffer_append(
106 &cmd_ctx->reply_payload.buffer, cmd_header_buf,
107 cmd_header_len);
108 if (ret) {
109 goto end;
110 }
111 }
112
113 /* Append payload. */
114 if (payload_len) {
115 ret = lttng_dynamic_buffer_append(
116 &cmd_ctx->reply_payload.buffer, payload_buf,
117 payload_len);
118 if (ret) {
119 goto end;
120 }
121 }
122
123 end:
124 return ret;
125 }
126
127 /*
128 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
129 * exec or it will fail.
130 */
131 static int spawn_consumer_thread(struct consumer_data *consumer_data)
132 {
133 return launch_consumer_management_thread(consumer_data) ? 0 : -1;
134 }
135
136 /*
137 * Fork and exec a consumer daemon (consumerd).
138 *
139 * Return pid if successful else -1.
140 */
141 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
142 {
143 int ret;
144 pid_t pid;
145 const char *consumer_to_use;
146 const char *verbosity;
147 struct stat st;
148
149 DBG("Spawning consumerd");
150
151 pid = fork();
152 if (pid == 0) {
153 /*
154 * Exec consumerd.
155 */
156 if (config.verbose_consumer) {
157 verbosity = "--verbose";
158 } else if (lttng_opt_quiet) {
159 verbosity = "--quiet";
160 } else {
161 verbosity = "";
162 }
163
164 switch (consumer_data->type) {
165 case LTTNG_CONSUMER_KERNEL:
166 /*
167 * Find out which consumerd to execute. We will first try the
168 * 64-bit path, then the sessiond's installation directory, and
169 * fallback on the 32-bit one,
170 */
171 DBG3("Looking for a kernel consumer at these locations:");
172 DBG3(" 1) %s", config.consumerd64_bin_path.value ? : "NULL");
173 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, DEFAULT_CONSUMERD_FILE);
174 DBG3(" 3) %s", config.consumerd32_bin_path.value ? : "NULL");
175 if (stat(config.consumerd64_bin_path.value, &st) == 0) {
176 DBG3("Found location #1");
177 consumer_to_use = config.consumerd64_bin_path.value;
178 } else if (stat(INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE, &st) == 0) {
179 DBG3("Found location #2");
180 consumer_to_use = INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE;
181 } else if (config.consumerd32_bin_path.value &&
182 stat(config.consumerd32_bin_path.value, &st) == 0) {
183 DBG3("Found location #3");
184 consumer_to_use = config.consumerd32_bin_path.value;
185 } else {
186 DBG("Could not find any valid consumerd executable");
187 ret = -EINVAL;
188 goto error;
189 }
190 DBG("Using kernel consumer at: %s", consumer_to_use);
191 (void) execl(consumer_to_use,
192 "lttng-consumerd", verbosity, "-k",
193 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
194 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
195 "--group", config.tracing_group_name.value,
196 NULL);
197 break;
198 case LTTNG_CONSUMER64_UST:
199 {
200 if (config.consumerd64_lib_dir.value) {
201 const char *tmp;
202 size_t tmplen;
203 char *tmpnew;
204
205 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
206 if (!tmp) {
207 tmp = "";
208 }
209 tmplen = strlen(config.consumerd64_lib_dir.value) + 1 /* : */ + strlen(tmp);
210 tmpnew = zmalloc(tmplen + 1 /* \0 */);
211 if (!tmpnew) {
212 ret = -ENOMEM;
213 goto error;
214 }
215 strcat(tmpnew, config.consumerd64_lib_dir.value);
216 if (tmp[0] != '\0') {
217 strcat(tmpnew, ":");
218 strcat(tmpnew, tmp);
219 }
220 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
221 free(tmpnew);
222 if (ret) {
223 ret = -errno;
224 goto error;
225 }
226 }
227 DBG("Using 64-bit UST consumer at: %s", config.consumerd64_bin_path.value);
228 (void) execl(config.consumerd64_bin_path.value, "lttng-consumerd", verbosity, "-u",
229 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
230 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
231 "--group", config.tracing_group_name.value,
232 NULL);
233 break;
234 }
235 case LTTNG_CONSUMER32_UST:
236 {
237 if (config.consumerd32_lib_dir.value) {
238 const char *tmp;
239 size_t tmplen;
240 char *tmpnew;
241
242 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
243 if (!tmp) {
244 tmp = "";
245 }
246 tmplen = strlen(config.consumerd32_lib_dir.value) + 1 /* : */ + strlen(tmp);
247 tmpnew = zmalloc(tmplen + 1 /* \0 */);
248 if (!tmpnew) {
249 ret = -ENOMEM;
250 goto error;
251 }
252 strcat(tmpnew, config.consumerd32_lib_dir.value);
253 if (tmp[0] != '\0') {
254 strcat(tmpnew, ":");
255 strcat(tmpnew, tmp);
256 }
257 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
258 free(tmpnew);
259 if (ret) {
260 ret = -errno;
261 goto error;
262 }
263 }
264 DBG("Using 32-bit UST consumer at: %s", config.consumerd32_bin_path.value);
265 (void) execl(config.consumerd32_bin_path.value, "lttng-consumerd", verbosity, "-u",
266 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
267 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
268 "--group", config.tracing_group_name.value,
269 NULL);
270 break;
271 }
272 default:
273 ERR("unknown consumer type");
274 errno = 0;
275 }
276 if (errno != 0) {
277 PERROR("Consumer execl()");
278 }
279 /* Reaching this point, we got a failure on our execl(). */
280 exit(EXIT_FAILURE);
281 } else if (pid > 0) {
282 ret = pid;
283 } else {
284 PERROR("start consumer fork");
285 ret = -errno;
286 }
287 error:
288 return ret;
289 }
290
291 /*
292 * Spawn the consumerd daemon and session daemon thread.
293 */
294 static int start_consumerd(struct consumer_data *consumer_data)
295 {
296 int ret;
297
298 /*
299 * Set the listen() state on the socket since there is a possible race
300 * between the exec() of the consumer daemon and this call if place in the
301 * consumer thread. See bug #366 for more details.
302 */
303 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
304 if (ret < 0) {
305 goto error;
306 }
307
308 pthread_mutex_lock(&consumer_data->pid_mutex);
309 if (consumer_data->pid != 0) {
310 pthread_mutex_unlock(&consumer_data->pid_mutex);
311 goto end;
312 }
313
314 ret = spawn_consumerd(consumer_data);
315 if (ret < 0) {
316 ERR("Spawning consumerd failed");
317 pthread_mutex_unlock(&consumer_data->pid_mutex);
318 goto error;
319 }
320
321 /* Setting up the consumer_data pid */
322 consumer_data->pid = ret;
323 DBG2("Consumer pid %d", consumer_data->pid);
324 pthread_mutex_unlock(&consumer_data->pid_mutex);
325
326 DBG2("Spawning consumer control thread");
327 ret = spawn_consumer_thread(consumer_data);
328 if (ret < 0) {
329 ERR("Fatal error spawning consumer control thread");
330 goto error;
331 }
332
333 end:
334 return 0;
335
336 error:
337 /* Cleanup already created sockets on error. */
338 if (consumer_data->err_sock >= 0) {
339 int err;
340
341 err = close(consumer_data->err_sock);
342 if (err < 0) {
343 PERROR("close consumer data error socket");
344 }
345 }
346 return ret;
347 }
348
349 /*
350 * Copy consumer output from the tracing session to the domain session. The
351 * function also applies the right modification on a per domain basis for the
352 * trace files destination directory.
353 *
354 * Should *NOT* be called with RCU read-side lock held.
355 */
356 static int copy_session_consumer(int domain, struct ltt_session *session)
357 {
358 int ret;
359 const char *dir_name;
360 struct consumer_output *consumer;
361
362 assert(session);
363 assert(session->consumer);
364
365 switch (domain) {
366 case LTTNG_DOMAIN_KERNEL:
367 DBG3("Copying tracing session consumer output in kernel session");
368 /*
369 * XXX: We should audit the session creation and what this function
370 * does "extra" in order to avoid a destroy since this function is used
371 * in the domain session creation (kernel and ust) only. Same for UST
372 * domain.
373 */
374 if (session->kernel_session->consumer) {
375 consumer_output_put(session->kernel_session->consumer);
376 }
377 session->kernel_session->consumer =
378 consumer_copy_output(session->consumer);
379 /* Ease our life a bit for the next part */
380 consumer = session->kernel_session->consumer;
381 dir_name = DEFAULT_KERNEL_TRACE_DIR;
382 break;
383 case LTTNG_DOMAIN_JUL:
384 case LTTNG_DOMAIN_LOG4J:
385 case LTTNG_DOMAIN_PYTHON:
386 case LTTNG_DOMAIN_UST:
387 DBG3("Copying tracing session consumer output in UST session");
388 if (session->ust_session->consumer) {
389 consumer_output_put(session->ust_session->consumer);
390 }
391 session->ust_session->consumer =
392 consumer_copy_output(session->consumer);
393 /* Ease our life a bit for the next part */
394 consumer = session->ust_session->consumer;
395 dir_name = DEFAULT_UST_TRACE_DIR;
396 break;
397 default:
398 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
399 goto error;
400 }
401
402 /* Append correct directory to subdir */
403 ret = lttng_strncpy(consumer->domain_subdir, dir_name,
404 sizeof(consumer->domain_subdir));
405 if (ret) {
406 ret = LTTNG_ERR_UNK;
407 goto error;
408 }
409 DBG3("Copy session consumer subdir %s", consumer->domain_subdir);
410 ret = LTTNG_OK;
411
412 error:
413 return ret;
414 }
415
416 /*
417 * Create an UST session and add it to the session ust list.
418 *
419 * Should *NOT* be called with RCU read-side lock held.
420 */
421 static int create_ust_session(struct ltt_session *session,
422 const struct lttng_domain *domain)
423 {
424 int ret;
425 struct ltt_ust_session *lus = NULL;
426
427 assert(session);
428 assert(domain);
429 assert(session->consumer);
430
431 switch (domain->type) {
432 case LTTNG_DOMAIN_JUL:
433 case LTTNG_DOMAIN_LOG4J:
434 case LTTNG_DOMAIN_PYTHON:
435 case LTTNG_DOMAIN_UST:
436 break;
437 default:
438 ERR("Unknown UST domain on create session %d", domain->type);
439 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
440 goto error;
441 }
442
443 DBG("Creating UST session");
444
445 lus = trace_ust_create_session(session->id);
446 if (lus == NULL) {
447 ret = LTTNG_ERR_UST_SESS_FAIL;
448 goto error;
449 }
450
451 lus->uid = session->uid;
452 lus->gid = session->gid;
453 lus->output_traces = session->output_traces;
454 lus->snapshot_mode = session->snapshot_mode;
455 lus->live_timer_interval = session->live_timer;
456 session->ust_session = lus;
457 if (session->shm_path[0]) {
458 strncpy(lus->root_shm_path, session->shm_path,
459 sizeof(lus->root_shm_path));
460 lus->root_shm_path[sizeof(lus->root_shm_path) - 1] = '\0';
461 strncpy(lus->shm_path, session->shm_path,
462 sizeof(lus->shm_path));
463 lus->shm_path[sizeof(lus->shm_path) - 1] = '\0';
464 strncat(lus->shm_path, "/ust",
465 sizeof(lus->shm_path) - strlen(lus->shm_path) - 1);
466 }
467 /* Copy session output to the newly created UST session */
468 ret = copy_session_consumer(domain->type, session);
469 if (ret != LTTNG_OK) {
470 goto error;
471 }
472
473 return LTTNG_OK;
474
475 error:
476 free(lus);
477 session->ust_session = NULL;
478 return ret;
479 }
480
481 /*
482 * Create a kernel tracer session then create the default channel.
483 */
484 static int create_kernel_session(struct ltt_session *session)
485 {
486 int ret;
487
488 DBG("Creating kernel session");
489
490 ret = kernel_create_session(session);
491 if (ret < 0) {
492 ret = LTTNG_ERR_KERN_SESS_FAIL;
493 goto error_create;
494 }
495
496 /* Code flow safety */
497 assert(session->kernel_session);
498
499 /* Copy session output to the newly created Kernel session */
500 ret = copy_session_consumer(LTTNG_DOMAIN_KERNEL, session);
501 if (ret != LTTNG_OK) {
502 goto error;
503 }
504
505 session->kernel_session->uid = session->uid;
506 session->kernel_session->gid = session->gid;
507 session->kernel_session->output_traces = session->output_traces;
508 session->kernel_session->snapshot_mode = session->snapshot_mode;
509 session->kernel_session->is_live_session = session->live_timer != 0;
510
511 return LTTNG_OK;
512
513 error:
514 trace_kernel_destroy_session(session->kernel_session);
515 session->kernel_session = NULL;
516 error_create:
517 return ret;
518 }
519
520 /*
521 * Count number of session permitted by uid/gid.
522 */
523 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
524 {
525 unsigned int i = 0;
526 struct ltt_session *session;
527 const struct ltt_session_list *session_list = session_get_list();
528
529 DBG("Counting number of available session for UID %d GID %d",
530 uid, gid);
531 cds_list_for_each_entry(session, &session_list->head, list) {
532 if (!session_get(session)) {
533 continue;
534 }
535 session_lock(session);
536 /* Only count the sessions the user can control. */
537 if (session_access_ok(session, uid, gid) &&
538 !session->destroyed) {
539 i++;
540 }
541 session_unlock(session);
542 session_put(session);
543 }
544 return i;
545 }
546
547 static int receive_userspace_probe(struct command_ctx *cmd_ctx, int sock,
548 int *sock_error, struct lttng_event *event)
549 {
550 int fd, ret;
551 struct lttng_userspace_probe_location *probe_location;
552 const struct lttng_userspace_probe_location_lookup_method *lookup = NULL;
553 struct lttng_dynamic_buffer probe_location_buffer;
554 struct lttng_buffer_view buffer_view;
555
556 /*
557 * Create a buffer to store the serialized version of the probe
558 * location.
559 */
560 lttng_dynamic_buffer_init(&probe_location_buffer);
561 ret = lttng_dynamic_buffer_set_size(&probe_location_buffer,
562 cmd_ctx->lsm.u.enable.userspace_probe_location_len);
563 if (ret) {
564 ret = LTTNG_ERR_NOMEM;
565 goto error;
566 }
567
568 /*
569 * Receive the probe location.
570 */
571 ret = lttcomm_recv_unix_sock(sock, probe_location_buffer.data,
572 probe_location_buffer.size);
573 if (ret <= 0) {
574 DBG("Nothing recv() from client var len data... continuing");
575 *sock_error = 1;
576 lttng_dynamic_buffer_reset(&probe_location_buffer);
577 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
578 goto error;
579 }
580
581 buffer_view = lttng_buffer_view_from_dynamic_buffer(
582 &probe_location_buffer, 0, probe_location_buffer.size);
583
584 /*
585 * Extract the probe location from the serialized version.
586 */
587 ret = lttng_userspace_probe_location_create_from_buffer(
588 &buffer_view, &probe_location);
589 if (ret < 0) {
590 WARN("Failed to create a userspace probe location from the received buffer");
591 lttng_dynamic_buffer_reset( &probe_location_buffer);
592 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
593 goto error;
594 }
595
596 /*
597 * Receive the file descriptor to the target binary from the client.
598 */
599 DBG("Receiving userspace probe target FD from client ...");
600 ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1);
601 if (ret <= 0) {
602 DBG("Nothing recv() from client userspace probe fd... continuing");
603 *sock_error = 1;
604 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
605 goto error;
606 }
607
608 /*
609 * Set the file descriptor received from the client through the unix
610 * socket in the probe location.
611 */
612 lookup = lttng_userspace_probe_location_get_lookup_method(probe_location);
613 if (!lookup) {
614 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
615 goto error;
616 }
617
618 /*
619 * From the kernel tracer's perspective, all userspace probe event types
620 * are all the same: a file and an offset.
621 */
622 switch (lttng_userspace_probe_location_lookup_method_get_type(lookup)) {
623 case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF:
624 ret = lttng_userspace_probe_location_function_set_binary_fd(
625 probe_location, fd);
626 break;
627 case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT:
628 ret = lttng_userspace_probe_location_tracepoint_set_binary_fd(
629 probe_location, fd);
630 break;
631 default:
632 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
633 goto error;
634 }
635
636 if (ret) {
637 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
638 goto error;
639 }
640
641 /* Attach the probe location to the event. */
642 ret = lttng_event_set_userspace_probe_location(event, probe_location);
643 if (ret) {
644 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
645 goto error;
646 }
647
648 lttng_dynamic_buffer_reset(&probe_location_buffer);
649 error:
650 return ret;
651 }
652
653 /*
654 * Version of setup_lttng_msg() without command header.
655 */
656 static int setup_lttng_msg_no_cmd_header(struct command_ctx *cmd_ctx,
657 void *payload_buf, size_t payload_len)
658 {
659 return setup_lttng_msg(cmd_ctx, payload_buf, payload_len, NULL, 0);
660 }
661
662 /*
663 * Check if the current kernel tracer supports the session rotation feature.
664 * Return 1 if it does, 0 otherwise.
665 */
666 static int check_rotate_compatible(void)
667 {
668 int ret = 1;
669
670 if (kernel_tracer_version.major != 2 || kernel_tracer_version.minor < 11) {
671 DBG("Kernel tracer version is not compatible with the rotation feature");
672 ret = 0;
673 }
674
675 return ret;
676 }
677
678 /*
679 * Send data on a unix socket using the liblttsessiondcomm API.
680 *
681 * Return lttcomm error code.
682 */
683 static int send_unix_sock(int sock, struct lttng_payload_view *view)
684 {
685 int ret;
686
687 /* Check valid length */
688 if (view->buffer.size == 0) {
689 ret = -1;
690 goto end;
691 }
692
693 ret = lttcomm_send_unix_sock(
694 sock, view->buffer.data, view->buffer.size);
695 if (ret < 0) {
696 goto end;
697 }
698
699 if (lttng_dynamic_array_get_count(&view->_fds) > 0) {
700 ret = lttcomm_send_fds_unix_sock(sock,
701 (const int *) view->_fds.buffer.data,
702 lttng_dynamic_array_get_count(&view->_fds));
703 }
704
705 end:
706 return ret;
707 }
708
709 /*
710 * Process the command requested by the lttng client within the command
711 * context structure. This function make sure that the return structure (llm)
712 * is set and ready for transmission before returning.
713 *
714 * Return any error encountered or 0 for success.
715 *
716 * "sock" is only used for special-case var. len data.
717 * A command may assume the ownership of the socket, in which case its value
718 * should be set to -1.
719 *
720 * Should *NOT* be called with RCU read-side lock held.
721 */
722 static int process_client_msg(struct command_ctx *cmd_ctx, int *sock,
723 int *sock_error)
724 {
725 int ret = LTTNG_OK;
726 int need_tracing_session = 1;
727 int need_domain;
728
729 DBG("Processing client command %d", cmd_ctx->lsm.cmd_type);
730
731 assert(!rcu_read_ongoing());
732
733 *sock_error = 0;
734
735 switch (cmd_ctx->lsm.cmd_type) {
736 case LTTNG_CREATE_SESSION_EXT:
737 case LTTNG_DESTROY_SESSION:
738 case LTTNG_LIST_SESSIONS:
739 case LTTNG_LIST_DOMAINS:
740 case LTTNG_START_TRACE:
741 case LTTNG_STOP_TRACE:
742 case LTTNG_DATA_PENDING:
743 case LTTNG_SNAPSHOT_ADD_OUTPUT:
744 case LTTNG_SNAPSHOT_DEL_OUTPUT:
745 case LTTNG_SNAPSHOT_LIST_OUTPUT:
746 case LTTNG_SNAPSHOT_RECORD:
747 case LTTNG_SAVE_SESSION:
748 case LTTNG_SET_SESSION_SHM_PATH:
749 case LTTNG_REGENERATE_METADATA:
750 case LTTNG_REGENERATE_STATEDUMP:
751 case LTTNG_REGISTER_TRIGGER:
752 case LTTNG_UNREGISTER_TRIGGER:
753 case LTTNG_ROTATE_SESSION:
754 case LTTNG_ROTATION_GET_INFO:
755 case LTTNG_ROTATION_SET_SCHEDULE:
756 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
757 case LTTNG_CLEAR_SESSION:
758 need_domain = 0;
759 break;
760 default:
761 need_domain = 1;
762 }
763
764 if (config.no_kernel && need_domain
765 && cmd_ctx->lsm.domain.type == LTTNG_DOMAIN_KERNEL) {
766 if (!is_root) {
767 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
768 } else {
769 ret = LTTNG_ERR_KERN_NA;
770 }
771 goto error;
772 }
773
774 /* Deny register consumer if we already have a spawned consumer. */
775 if (cmd_ctx->lsm.cmd_type == LTTNG_REGISTER_CONSUMER) {
776 pthread_mutex_lock(&kconsumer_data.pid_mutex);
777 if (kconsumer_data.pid > 0) {
778 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
779 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
780 goto error;
781 }
782 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
783 }
784
785 /*
786 * Check for command that don't needs to allocate a returned payload. We do
787 * this here so we don't have to make the call for no payload at each
788 * command.
789 */
790 switch(cmd_ctx->lsm.cmd_type) {
791 case LTTNG_LIST_SESSIONS:
792 case LTTNG_LIST_TRACEPOINTS:
793 case LTTNG_LIST_TRACEPOINT_FIELDS:
794 case LTTNG_LIST_DOMAINS:
795 case LTTNG_LIST_CHANNELS:
796 case LTTNG_LIST_EVENTS:
797 case LTTNG_LIST_SYSCALLS:
798 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
799 case LTTNG_PROCESS_ATTR_TRACKER_GET_POLICY:
800 case LTTNG_PROCESS_ATTR_TRACKER_GET_INCLUSION_SET:
801 case LTTNG_DATA_PENDING:
802 case LTTNG_ROTATE_SESSION:
803 case LTTNG_ROTATION_GET_INFO:
804 break;
805 default:
806 /* Setup lttng message with no payload */
807 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0);
808 if (ret < 0) {
809 /* This label does not try to unlock the session */
810 goto init_setup_error;
811 }
812 }
813
814 /* Commands that DO NOT need a session. */
815 switch (cmd_ctx->lsm.cmd_type) {
816 case LTTNG_CREATE_SESSION_EXT:
817 case LTTNG_LIST_SESSIONS:
818 case LTTNG_LIST_TRACEPOINTS:
819 case LTTNG_LIST_SYSCALLS:
820 case LTTNG_LIST_TRACEPOINT_FIELDS:
821 case LTTNG_SAVE_SESSION:
822 case LTTNG_REGISTER_TRIGGER:
823 case LTTNG_UNREGISTER_TRIGGER:
824 need_tracing_session = 0;
825 break;
826 default:
827 DBG("Getting session %s by name", cmd_ctx->lsm.session.name);
828 /*
829 * We keep the session list lock across _all_ commands
830 * for now, because the per-session lock does not
831 * handle teardown properly.
832 */
833 session_lock_list();
834 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm.session.name);
835 if (cmd_ctx->session == NULL) {
836 ret = LTTNG_ERR_SESS_NOT_FOUND;
837 goto error;
838 } else {
839 /* Acquire lock for the session */
840 session_lock(cmd_ctx->session);
841 }
842 break;
843 }
844
845 /*
846 * Commands that need a valid session but should NOT create one if none
847 * exists. Instead of creating one and destroying it when the command is
848 * handled, process that right before so we save some round trip in useless
849 * code path.
850 */
851 switch (cmd_ctx->lsm.cmd_type) {
852 case LTTNG_DISABLE_CHANNEL:
853 case LTTNG_DISABLE_EVENT:
854 switch (cmd_ctx->lsm.domain.type) {
855 case LTTNG_DOMAIN_KERNEL:
856 if (!cmd_ctx->session->kernel_session) {
857 ret = LTTNG_ERR_NO_CHANNEL;
858 goto error;
859 }
860 break;
861 case LTTNG_DOMAIN_JUL:
862 case LTTNG_DOMAIN_LOG4J:
863 case LTTNG_DOMAIN_PYTHON:
864 case LTTNG_DOMAIN_UST:
865 if (!cmd_ctx->session->ust_session) {
866 ret = LTTNG_ERR_NO_CHANNEL;
867 goto error;
868 }
869 break;
870 default:
871 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
872 goto error;
873 }
874 default:
875 break;
876 }
877
878 if (!need_domain) {
879 goto skip_domain;
880 }
881
882 /*
883 * Check domain type for specific "pre-action".
884 */
885 switch (cmd_ctx->lsm.domain.type) {
886 case LTTNG_DOMAIN_KERNEL:
887 if (!is_root) {
888 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
889 goto error;
890 }
891
892 /* Kernel tracer check */
893 if (!kernel_tracer_is_initialized()) {
894 /* Basically, load kernel tracer modules */
895 ret = init_kernel_tracer();
896 if (ret != 0) {
897 goto error;
898 }
899 }
900
901 /* Consumer is in an ERROR state. Report back to client */
902 if (uatomic_read(&kernel_consumerd_state) == CONSUMER_ERROR) {
903 ret = LTTNG_ERR_NO_KERNCONSUMERD;
904 goto error;
905 }
906
907 /* Need a session for kernel command */
908 if (need_tracing_session) {
909 if (cmd_ctx->session->kernel_session == NULL) {
910 ret = create_kernel_session(cmd_ctx->session);
911 if (ret != LTTNG_OK) {
912 ret = LTTNG_ERR_KERN_SESS_FAIL;
913 goto error;
914 }
915 }
916
917 /* Start the kernel consumer daemon */
918 pthread_mutex_lock(&kconsumer_data.pid_mutex);
919 if (kconsumer_data.pid == 0 &&
920 cmd_ctx->lsm.cmd_type != LTTNG_REGISTER_CONSUMER) {
921 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
922 ret = start_consumerd(&kconsumer_data);
923 if (ret < 0) {
924 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
925 goto error;
926 }
927 uatomic_set(&kernel_consumerd_state, CONSUMER_STARTED);
928 } else {
929 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
930 }
931
932 /*
933 * The consumer was just spawned so we need to add the socket to
934 * the consumer output of the session if exist.
935 */
936 ret = consumer_create_socket(&kconsumer_data,
937 cmd_ctx->session->kernel_session->consumer);
938 if (ret < 0) {
939 goto error;
940 }
941 }
942
943 break;
944 case LTTNG_DOMAIN_JUL:
945 case LTTNG_DOMAIN_LOG4J:
946 case LTTNG_DOMAIN_PYTHON:
947 case LTTNG_DOMAIN_UST:
948 {
949 if (!ust_app_supported()) {
950 ret = LTTNG_ERR_NO_UST;
951 goto error;
952 }
953 /* Consumer is in an ERROR state. Report back to client */
954 if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) {
955 ret = LTTNG_ERR_NO_USTCONSUMERD;
956 goto error;
957 }
958
959 if (need_tracing_session) {
960 /* Create UST session if none exist. */
961 if (cmd_ctx->session->ust_session == NULL) {
962 ret = create_ust_session(cmd_ctx->session,
963 ALIGNED_CONST_PTR(cmd_ctx->lsm.domain));
964 if (ret != LTTNG_OK) {
965 goto error;
966 }
967 }
968
969 /* Start the UST consumer daemons */
970 /* 64-bit */
971 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
972 if (config.consumerd64_bin_path.value &&
973 ustconsumer64_data.pid == 0 &&
974 cmd_ctx->lsm.cmd_type != LTTNG_REGISTER_CONSUMER) {
975 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
976 ret = start_consumerd(&ustconsumer64_data);
977 if (ret < 0) {
978 ret = LTTNG_ERR_UST_CONSUMER64_FAIL;
979 uatomic_set(&ust_consumerd64_fd, -EINVAL);
980 goto error;
981 }
982
983 uatomic_set(&ust_consumerd64_fd, ustconsumer64_data.cmd_sock);
984 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
985 } else {
986 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
987 }
988
989 /*
990 * Setup socket for consumer 64 bit. No need for atomic access
991 * since it was set above and can ONLY be set in this thread.
992 */
993 ret = consumer_create_socket(&ustconsumer64_data,
994 cmd_ctx->session->ust_session->consumer);
995 if (ret < 0) {
996 goto error;
997 }
998
999 /* 32-bit */
1000 pthread_mutex_lock(&ustconsumer32_data.pid_mutex);
1001 if (config.consumerd32_bin_path.value &&
1002 ustconsumer32_data.pid == 0 &&
1003 cmd_ctx->lsm.cmd_type != LTTNG_REGISTER_CONSUMER) {
1004 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
1005 ret = start_consumerd(&ustconsumer32_data);
1006 if (ret < 0) {
1007 ret = LTTNG_ERR_UST_CONSUMER32_FAIL;
1008 uatomic_set(&ust_consumerd32_fd, -EINVAL);
1009 goto error;
1010 }
1011
1012 uatomic_set(&ust_consumerd32_fd, ustconsumer32_data.cmd_sock);
1013 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
1014 } else {
1015 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
1016 }
1017
1018 /*
1019 * Setup socket for consumer 32 bit. No need for atomic access
1020 * since it was set above and can ONLY be set in this thread.
1021 */
1022 ret = consumer_create_socket(&ustconsumer32_data,
1023 cmd_ctx->session->ust_session->consumer);
1024 if (ret < 0) {
1025 goto error;
1026 }
1027 }
1028 break;
1029 }
1030 default:
1031 break;
1032 }
1033 skip_domain:
1034
1035 /* Validate consumer daemon state when start/stop trace command */
1036 if (cmd_ctx->lsm.cmd_type == LTTNG_START_TRACE ||
1037 cmd_ctx->lsm.cmd_type == LTTNG_STOP_TRACE) {
1038 switch (cmd_ctx->lsm.domain.type) {
1039 case LTTNG_DOMAIN_NONE:
1040 break;
1041 case LTTNG_DOMAIN_JUL:
1042 case LTTNG_DOMAIN_LOG4J:
1043 case LTTNG_DOMAIN_PYTHON:
1044 case LTTNG_DOMAIN_UST:
1045 if (uatomic_read(&ust_consumerd_state) != CONSUMER_STARTED) {
1046 ret = LTTNG_ERR_NO_USTCONSUMERD;
1047 goto error;
1048 }
1049 break;
1050 case LTTNG_DOMAIN_KERNEL:
1051 if (uatomic_read(&kernel_consumerd_state) != CONSUMER_STARTED) {
1052 ret = LTTNG_ERR_NO_KERNCONSUMERD;
1053 goto error;
1054 }
1055 break;
1056 default:
1057 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1058 goto error;
1059 }
1060 }
1061
1062 /*
1063 * Check that the UID or GID match that of the tracing session.
1064 * The root user can interact with all sessions.
1065 */
1066 if (need_tracing_session) {
1067 if (!session_access_ok(cmd_ctx->session,
1068 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1069 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds)) ||
1070 cmd_ctx->session->destroyed) {
1071 ret = LTTNG_ERR_EPERM;
1072 goto error;
1073 }
1074 }
1075
1076 /*
1077 * Send relayd information to consumer as soon as we have a domain and a
1078 * session defined.
1079 */
1080 if (cmd_ctx->session && need_domain) {
1081 /*
1082 * Setup relayd if not done yet. If the relayd information was already
1083 * sent to the consumer, this call will gracefully return.
1084 */
1085 ret = cmd_setup_relayd(cmd_ctx->session);
1086 if (ret != LTTNG_OK) {
1087 goto error;
1088 }
1089 }
1090
1091 /* Process by command type */
1092 switch (cmd_ctx->lsm.cmd_type) {
1093 case LTTNG_ADD_CONTEXT:
1094 {
1095 /*
1096 * An LTTNG_ADD_CONTEXT command might have a supplementary
1097 * payload if the context being added is an application context.
1098 */
1099 if (cmd_ctx->lsm.u.context.ctx.ctx ==
1100 LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1101 char *provider_name = NULL, *context_name = NULL;
1102 size_t provider_name_len =
1103 cmd_ctx->lsm.u.context.provider_name_len;
1104 size_t context_name_len =
1105 cmd_ctx->lsm.u.context.context_name_len;
1106
1107 if (provider_name_len == 0 || context_name_len == 0) {
1108 /*
1109 * Application provider and context names MUST
1110 * be provided.
1111 */
1112 ret = -LTTNG_ERR_INVALID;
1113 goto error;
1114 }
1115
1116 provider_name = zmalloc(provider_name_len + 1);
1117 if (!provider_name) {
1118 ret = -LTTNG_ERR_NOMEM;
1119 goto error;
1120 }
1121 cmd_ctx->lsm.u.context.ctx.u.app_ctx.provider_name =
1122 provider_name;
1123
1124 context_name = zmalloc(context_name_len + 1);
1125 if (!context_name) {
1126 ret = -LTTNG_ERR_NOMEM;
1127 goto error_add_context;
1128 }
1129 cmd_ctx->lsm.u.context.ctx.u.app_ctx.ctx_name =
1130 context_name;
1131
1132 ret = lttcomm_recv_unix_sock(*sock, provider_name,
1133 provider_name_len);
1134 if (ret < 0) {
1135 goto error_add_context;
1136 }
1137
1138 ret = lttcomm_recv_unix_sock(*sock, context_name,
1139 context_name_len);
1140 if (ret < 0) {
1141 goto error_add_context;
1142 }
1143 }
1144
1145 /*
1146 * cmd_add_context assumes ownership of the provider and context
1147 * names.
1148 */
1149 ret = cmd_add_context(cmd_ctx->session,
1150 cmd_ctx->lsm.domain.type,
1151 cmd_ctx->lsm.u.context.channel_name,
1152 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.context.ctx),
1153 kernel_poll_pipe[1]);
1154
1155 cmd_ctx->lsm.u.context.ctx.u.app_ctx.provider_name = NULL;
1156 cmd_ctx->lsm.u.context.ctx.u.app_ctx.ctx_name = NULL;
1157 error_add_context:
1158 free(cmd_ctx->lsm.u.context.ctx.u.app_ctx.provider_name);
1159 free(cmd_ctx->lsm.u.context.ctx.u.app_ctx.ctx_name);
1160 if (ret < 0) {
1161 goto error;
1162 }
1163 break;
1164 }
1165 case LTTNG_DISABLE_CHANNEL:
1166 {
1167 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm.domain.type,
1168 cmd_ctx->lsm.u.disable.channel_name);
1169 break;
1170 }
1171 case LTTNG_DISABLE_EVENT:
1172 {
1173
1174 /*
1175 * FIXME: handle filter; for now we just receive the filter's
1176 * bytecode along with the filter expression which are sent by
1177 * liblttng-ctl and discard them.
1178 *
1179 * This fixes an issue where the client may block while sending
1180 * the filter payload and encounter an error because the session
1181 * daemon closes the socket without ever handling this data.
1182 */
1183 size_t count = cmd_ctx->lsm.u.disable.expression_len +
1184 cmd_ctx->lsm.u.disable.bytecode_len;
1185
1186 if (count) {
1187 char data[LTTNG_FILTER_MAX_LEN];
1188
1189 DBG("Discarding disable event command payload of size %zu", count);
1190 while (count) {
1191 ret = lttcomm_recv_unix_sock(*sock, data,
1192 count > sizeof(data) ? sizeof(data) : count);
1193 if (ret < 0) {
1194 goto error;
1195 }
1196
1197 count -= (size_t) ret;
1198 }
1199 }
1200 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm.domain.type,
1201 cmd_ctx->lsm.u.disable.channel_name,
1202 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.disable.event));
1203 break;
1204 }
1205 case LTTNG_ENABLE_CHANNEL:
1206 {
1207 cmd_ctx->lsm.u.channel.chan.attr.extended.ptr =
1208 (struct lttng_channel_extended *) &cmd_ctx->lsm.u.channel.extended;
1209 ret = cmd_enable_channel(cmd_ctx->session,
1210 ALIGNED_CONST_PTR(cmd_ctx->lsm.domain),
1211 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.channel.chan),
1212 kernel_poll_pipe[1]);
1213 break;
1214 }
1215 case LTTNG_PROCESS_ATTR_TRACKER_ADD_INCLUDE_VALUE:
1216 case LTTNG_PROCESS_ATTR_TRACKER_REMOVE_INCLUDE_VALUE:
1217 {
1218 struct lttng_dynamic_buffer payload;
1219 struct lttng_buffer_view payload_view;
1220 const bool add_value =
1221 cmd_ctx->lsm.cmd_type ==
1222 LTTNG_PROCESS_ATTR_TRACKER_ADD_INCLUDE_VALUE;
1223 const size_t name_len =
1224 cmd_ctx->lsm.u.process_attr_tracker_add_remove_include_value
1225 .name_len;
1226 const enum lttng_domain_type domain_type =
1227 (enum lttng_domain_type)
1228 cmd_ctx->lsm.domain.type;
1229 const enum lttng_process_attr process_attr =
1230 (enum lttng_process_attr) cmd_ctx->lsm.u
1231 .process_attr_tracker_add_remove_include_value
1232 .process_attr;
1233 const enum lttng_process_attr_value_type value_type =
1234 (enum lttng_process_attr_value_type) cmd_ctx
1235 ->lsm.u
1236 .process_attr_tracker_add_remove_include_value
1237 .value_type;
1238 struct process_attr_value *value;
1239 enum lttng_error_code ret_code;
1240
1241 /* Receive remaining variable length payload if applicable. */
1242 if (name_len > LOGIN_NAME_MAX) {
1243 /*
1244 * POSIX mandates user and group names that are at least
1245 * 8 characters long. Note that although shadow-utils
1246 * (useradd, groupaadd, etc.) use 32 chars as their
1247 * limit (from bits/utmp.h, UT_NAMESIZE),
1248 * LOGIN_NAME_MAX is defined to 256.
1249 */
1250 ERR("Rejecting process attribute tracker value %s as the provided exceeds the maximal allowed length: argument length = %zu, maximal length = %d",
1251 add_value ? "addition" : "removal",
1252 name_len, LOGIN_NAME_MAX);
1253 ret = LTTNG_ERR_INVALID;
1254 goto error;
1255 }
1256
1257 lttng_dynamic_buffer_init(&payload);
1258 if (name_len != 0) {
1259 /*
1260 * Receive variable payload for user/group name
1261 * arguments.
1262 */
1263 ret = lttng_dynamic_buffer_set_size(&payload, name_len);
1264 if (ret) {
1265 ERR("Failed to allocate buffer to receive payload of %s process attribute tracker value argument",
1266 add_value ? "add" : "remove");
1267 ret = LTTNG_ERR_NOMEM;
1268 goto error_add_remove_tracker_value;
1269 }
1270
1271 ret = lttcomm_recv_unix_sock(
1272 *sock, payload.data, name_len);
1273 if (ret <= 0) {
1274 ERR("Failed to receive payload of %s process attribute tracker value argument",
1275 add_value ? "add" : "remove");
1276 *sock_error = 1;
1277 ret = LTTNG_ERR_INVALID_PROTOCOL;
1278 goto error_add_remove_tracker_value;
1279 }
1280 }
1281
1282 payload_view = lttng_buffer_view_from_dynamic_buffer(
1283 &payload, 0, name_len);
1284 /*
1285 * Validate the value type and domains are legal for the process
1286 * attribute tracker that is specified and convert the value to
1287 * add/remove to the internal sessiond representation.
1288 */
1289 ret_code = process_attr_value_from_comm(domain_type,
1290 process_attr, value_type,
1291 &cmd_ctx->lsm.u.process_attr_tracker_add_remove_include_value
1292 .integral_value,
1293 &payload_view, &value);
1294 if (ret_code != LTTNG_OK) {
1295 ret = ret_code;
1296 goto error_add_remove_tracker_value;
1297 }
1298
1299 if (add_value) {
1300 ret = cmd_process_attr_tracker_inclusion_set_add_value(
1301 cmd_ctx->session, domain_type,
1302 process_attr, value);
1303 } else {
1304 ret = cmd_process_attr_tracker_inclusion_set_remove_value(
1305 cmd_ctx->session, domain_type,
1306 process_attr, value);
1307 }
1308 process_attr_value_destroy(value);
1309 error_add_remove_tracker_value:
1310 lttng_dynamic_buffer_reset(&payload);
1311 break;
1312 }
1313 case LTTNG_PROCESS_ATTR_TRACKER_GET_POLICY:
1314 {
1315 enum lttng_tracking_policy tracking_policy;
1316 const enum lttng_domain_type domain_type =
1317 (enum lttng_domain_type)
1318 cmd_ctx->lsm.domain.type;
1319 const enum lttng_process_attr process_attr =
1320 (enum lttng_process_attr) cmd_ctx->lsm.u
1321 .process_attr_tracker_get_tracking_policy
1322 .process_attr;
1323
1324 ret = cmd_process_attr_tracker_get_tracking_policy(
1325 cmd_ctx->session, domain_type, process_attr,
1326 &tracking_policy);
1327 if (ret != LTTNG_OK) {
1328 goto error;
1329 }
1330
1331 ret = setup_lttng_msg_no_cmd_header(cmd_ctx,
1332 &(uint32_t){tracking_policy}, sizeof(uint32_t));
1333 if (ret < 0) {
1334 ret = LTTNG_ERR_NOMEM;
1335 goto error;
1336 }
1337 ret = LTTNG_OK;
1338 break;
1339 }
1340 case LTTNG_PROCESS_ATTR_TRACKER_SET_POLICY:
1341 {
1342 const enum lttng_tracking_policy tracking_policy =
1343 (enum lttng_tracking_policy) cmd_ctx->lsm.u
1344 .process_attr_tracker_set_tracking_policy
1345 .tracking_policy;
1346 const enum lttng_domain_type domain_type =
1347 (enum lttng_domain_type)
1348 cmd_ctx->lsm.domain.type;
1349 const enum lttng_process_attr process_attr =
1350 (enum lttng_process_attr) cmd_ctx->lsm.u
1351 .process_attr_tracker_set_tracking_policy
1352 .process_attr;
1353
1354 ret = cmd_process_attr_tracker_set_tracking_policy(
1355 cmd_ctx->session, domain_type, process_attr,
1356 tracking_policy);
1357 if (ret != LTTNG_OK) {
1358 goto error;
1359 }
1360 break;
1361 }
1362 case LTTNG_PROCESS_ATTR_TRACKER_GET_INCLUSION_SET:
1363 {
1364 struct lttng_process_attr_values *values;
1365 struct lttng_dynamic_buffer reply;
1366 const enum lttng_domain_type domain_type =
1367 (enum lttng_domain_type)
1368 cmd_ctx->lsm.domain.type;
1369 const enum lttng_process_attr process_attr =
1370 (enum lttng_process_attr) cmd_ctx->lsm.u
1371 .process_attr_tracker_get_inclusion_set
1372 .process_attr;
1373
1374 ret = cmd_process_attr_tracker_get_inclusion_set(
1375 cmd_ctx->session, domain_type, process_attr,
1376 &values);
1377 if (ret != LTTNG_OK) {
1378 goto error;
1379 }
1380
1381 lttng_dynamic_buffer_init(&reply);
1382 ret = lttng_process_attr_values_serialize(values, &reply);
1383 if (ret < 0) {
1384 goto error_tracker_get_inclusion_set;
1385 }
1386
1387 ret = setup_lttng_msg_no_cmd_header(
1388 cmd_ctx, reply.data, reply.size);
1389 if (ret < 0) {
1390 ret = LTTNG_ERR_NOMEM;
1391 goto error_tracker_get_inclusion_set;
1392 }
1393 ret = LTTNG_OK;
1394
1395 error_tracker_get_inclusion_set:
1396 lttng_process_attr_values_destroy(values);
1397 lttng_dynamic_buffer_reset(&reply);
1398 break;
1399 }
1400 case LTTNG_ENABLE_EVENT:
1401 {
1402 struct lttng_event *ev = NULL;
1403 struct lttng_event_exclusion *exclusion = NULL;
1404 struct lttng_filter_bytecode *bytecode = NULL;
1405 char *filter_expression = NULL;
1406
1407 /* Handle exclusion events and receive it from the client. */
1408 if (cmd_ctx->lsm.u.enable.exclusion_count > 0) {
1409 size_t count = cmd_ctx->lsm.u.enable.exclusion_count;
1410
1411 exclusion = zmalloc(sizeof(struct lttng_event_exclusion) +
1412 (count * LTTNG_SYMBOL_NAME_LEN));
1413 if (!exclusion) {
1414 ret = LTTNG_ERR_EXCLUSION_NOMEM;
1415 goto error;
1416 }
1417
1418 DBG("Receiving var len exclusion event list from client ...");
1419 exclusion->count = count;
1420 ret = lttcomm_recv_unix_sock(*sock, exclusion->names,
1421 count * LTTNG_SYMBOL_NAME_LEN);
1422 if (ret <= 0) {
1423 DBG("Nothing recv() from client var len data... continuing");
1424 *sock_error = 1;
1425 free(exclusion);
1426 ret = LTTNG_ERR_EXCLUSION_INVAL;
1427 goto error;
1428 }
1429 }
1430
1431 /* Get filter expression from client. */
1432 if (cmd_ctx->lsm.u.enable.expression_len > 0) {
1433 size_t expression_len =
1434 cmd_ctx->lsm.u.enable.expression_len;
1435
1436 if (expression_len > LTTNG_FILTER_MAX_LEN) {
1437 ret = LTTNG_ERR_FILTER_INVAL;
1438 free(exclusion);
1439 goto error;
1440 }
1441
1442 filter_expression = zmalloc(expression_len);
1443 if (!filter_expression) {
1444 free(exclusion);
1445 ret = LTTNG_ERR_FILTER_NOMEM;
1446 goto error;
1447 }
1448
1449 /* Receive var. len. data */
1450 DBG("Receiving var len filter's expression from client ...");
1451 ret = lttcomm_recv_unix_sock(*sock, filter_expression,
1452 expression_len);
1453 if (ret <= 0) {
1454 DBG("Nothing recv() from client var len data... continuing");
1455 *sock_error = 1;
1456 free(filter_expression);
1457 free(exclusion);
1458 ret = LTTNG_ERR_FILTER_INVAL;
1459 goto error;
1460 }
1461 }
1462
1463 /* Handle filter and get bytecode from client. */
1464 if (cmd_ctx->lsm.u.enable.bytecode_len > 0) {
1465 size_t bytecode_len = cmd_ctx->lsm.u.enable.bytecode_len;
1466
1467 if (bytecode_len > LTTNG_FILTER_MAX_LEN) {
1468 ret = LTTNG_ERR_FILTER_INVAL;
1469 free(filter_expression);
1470 free(exclusion);
1471 goto error;
1472 }
1473
1474 bytecode = zmalloc(bytecode_len);
1475 if (!bytecode) {
1476 free(filter_expression);
1477 free(exclusion);
1478 ret = LTTNG_ERR_FILTER_NOMEM;
1479 goto error;
1480 }
1481
1482 /* Receive var. len. data */
1483 DBG("Receiving var len filter's bytecode from client ...");
1484 ret = lttcomm_recv_unix_sock(*sock, bytecode, bytecode_len);
1485 if (ret <= 0) {
1486 DBG("Nothing recv() from client var len data... continuing");
1487 *sock_error = 1;
1488 free(filter_expression);
1489 free(bytecode);
1490 free(exclusion);
1491 ret = LTTNG_ERR_FILTER_INVAL;
1492 goto error;
1493 }
1494
1495 if ((bytecode->len + sizeof(*bytecode)) != bytecode_len) {
1496 free(filter_expression);
1497 free(bytecode);
1498 free(exclusion);
1499 ret = LTTNG_ERR_FILTER_INVAL;
1500 goto error;
1501 }
1502 }
1503
1504 ev = lttng_event_copy(ALIGNED_CONST_PTR(cmd_ctx->lsm.u.enable.event));
1505 if (!ev) {
1506 DBG("Failed to copy event: %s",
1507 cmd_ctx->lsm.u.enable.event.name);
1508 free(filter_expression);
1509 free(bytecode);
1510 free(exclusion);
1511 ret = LTTNG_ERR_NOMEM;
1512 goto error;
1513 }
1514
1515
1516 if (cmd_ctx->lsm.u.enable.userspace_probe_location_len > 0) {
1517 /* Expect a userspace probe description. */
1518 ret = receive_userspace_probe(cmd_ctx, *sock, sock_error, ev);
1519 if (ret) {
1520 free(filter_expression);
1521 free(bytecode);
1522 free(exclusion);
1523 lttng_event_destroy(ev);
1524 goto error;
1525 }
1526 }
1527
1528 ret = cmd_enable_event(cmd_ctx->session,
1529 ALIGNED_CONST_PTR(cmd_ctx->lsm.domain),
1530 cmd_ctx->lsm.u.enable.channel_name,
1531 ev,
1532 filter_expression, bytecode, exclusion,
1533 kernel_poll_pipe[1]);
1534 lttng_event_destroy(ev);
1535 break;
1536 }
1537 case LTTNG_LIST_TRACEPOINTS:
1538 {
1539 struct lttng_event *events;
1540 ssize_t nb_events;
1541
1542 session_lock_list();
1543 nb_events = cmd_list_tracepoints(cmd_ctx->lsm.domain.type, &events);
1544 session_unlock_list();
1545 if (nb_events < 0) {
1546 /* Return value is a negative lttng_error_code. */
1547 ret = -nb_events;
1548 goto error;
1549 }
1550
1551 /*
1552 * Setup lttng message with payload size set to the event list size in
1553 * bytes and then copy list into the llm payload.
1554 */
1555 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, events,
1556 sizeof(struct lttng_event) * nb_events);
1557 free(events);
1558
1559 if (ret < 0) {
1560 goto setup_error;
1561 }
1562
1563 ret = LTTNG_OK;
1564 break;
1565 }
1566 case LTTNG_LIST_TRACEPOINT_FIELDS:
1567 {
1568 struct lttng_event_field *fields;
1569 ssize_t nb_fields;
1570
1571 session_lock_list();
1572 nb_fields = cmd_list_tracepoint_fields(cmd_ctx->lsm.domain.type,
1573 &fields);
1574 session_unlock_list();
1575 if (nb_fields < 0) {
1576 /* Return value is a negative lttng_error_code. */
1577 ret = -nb_fields;
1578 goto error;
1579 }
1580
1581 /*
1582 * Setup lttng message with payload size set to the event list size in
1583 * bytes and then copy list into the llm payload.
1584 */
1585 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, fields,
1586 sizeof(struct lttng_event_field) * nb_fields);
1587 free(fields);
1588
1589 if (ret < 0) {
1590 goto setup_error;
1591 }
1592
1593 ret = LTTNG_OK;
1594 break;
1595 }
1596 case LTTNG_LIST_SYSCALLS:
1597 {
1598 struct lttng_event *events;
1599 ssize_t nb_events;
1600
1601 nb_events = cmd_list_syscalls(&events);
1602 if (nb_events < 0) {
1603 /* Return value is a negative lttng_error_code. */
1604 ret = -nb_events;
1605 goto error;
1606 }
1607
1608 /*
1609 * Setup lttng message with payload size set to the event list size in
1610 * bytes and then copy list into the llm payload.
1611 */
1612 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, events,
1613 sizeof(struct lttng_event) * nb_events);
1614 free(events);
1615
1616 if (ret < 0) {
1617 goto setup_error;
1618 }
1619
1620 ret = LTTNG_OK;
1621 break;
1622 }
1623 case LTTNG_SET_CONSUMER_URI:
1624 {
1625 size_t nb_uri, len;
1626 struct lttng_uri *uris;
1627
1628 nb_uri = cmd_ctx->lsm.u.uri.size;
1629 len = nb_uri * sizeof(struct lttng_uri);
1630
1631 if (nb_uri == 0) {
1632 ret = LTTNG_ERR_INVALID;
1633 goto error;
1634 }
1635
1636 uris = zmalloc(len);
1637 if (uris == NULL) {
1638 ret = LTTNG_ERR_FATAL;
1639 goto error;
1640 }
1641
1642 /* Receive variable len data */
1643 DBG("Receiving %zu URI(s) from client ...", nb_uri);
1644 ret = lttcomm_recv_unix_sock(*sock, uris, len);
1645 if (ret <= 0) {
1646 DBG("No URIs received from client... continuing");
1647 *sock_error = 1;
1648 ret = LTTNG_ERR_SESSION_FAIL;
1649 free(uris);
1650 goto error;
1651 }
1652
1653 ret = cmd_set_consumer_uri(cmd_ctx->session, nb_uri, uris);
1654 free(uris);
1655 if (ret != LTTNG_OK) {
1656 goto error;
1657 }
1658
1659
1660 break;
1661 }
1662 case LTTNG_START_TRACE:
1663 {
1664 /*
1665 * On the first start, if we have a kernel session and we have
1666 * enabled time or size-based rotations, we have to make sure
1667 * the kernel tracer supports it.
1668 */
1669 if (!cmd_ctx->session->has_been_started && \
1670 cmd_ctx->session->kernel_session && \
1671 (cmd_ctx->session->rotate_timer_period || \
1672 cmd_ctx->session->rotate_size) && \
1673 !check_rotate_compatible()) {
1674 DBG("Kernel tracer version is not compatible with the rotation feature");
1675 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
1676 goto error;
1677 }
1678 ret = cmd_start_trace(cmd_ctx->session);
1679 break;
1680 }
1681 case LTTNG_STOP_TRACE:
1682 {
1683 ret = cmd_stop_trace(cmd_ctx->session);
1684 break;
1685 }
1686 case LTTNG_DESTROY_SESSION:
1687 {
1688 ret = cmd_destroy_session(cmd_ctx->session,
1689 notification_thread_handle,
1690 sock);
1691 break;
1692 }
1693 case LTTNG_LIST_DOMAINS:
1694 {
1695 ssize_t nb_dom;
1696 struct lttng_domain *domains = NULL;
1697
1698 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
1699 if (nb_dom < 0) {
1700 /* Return value is a negative lttng_error_code. */
1701 ret = -nb_dom;
1702 goto error;
1703 }
1704
1705 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, domains,
1706 nb_dom * sizeof(struct lttng_domain));
1707 free(domains);
1708
1709 if (ret < 0) {
1710 goto setup_error;
1711 }
1712
1713 ret = LTTNG_OK;
1714 break;
1715 }
1716 case LTTNG_LIST_CHANNELS:
1717 {
1718 ssize_t payload_size;
1719 struct lttng_channel *channels = NULL;
1720
1721 payload_size = cmd_list_channels(cmd_ctx->lsm.domain.type,
1722 cmd_ctx->session, &channels);
1723 if (payload_size < 0) {
1724 /* Return value is a negative lttng_error_code. */
1725 ret = -payload_size;
1726 goto error;
1727 }
1728
1729 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, channels,
1730 payload_size);
1731 free(channels);
1732
1733 if (ret < 0) {
1734 goto setup_error;
1735 }
1736
1737 ret = LTTNG_OK;
1738 break;
1739 }
1740 case LTTNG_LIST_EVENTS:
1741 {
1742 ssize_t nb_event;
1743 struct lttng_event *events = NULL;
1744 struct lttcomm_event_command_header cmd_header;
1745 size_t total_size;
1746
1747 memset(&cmd_header, 0, sizeof(cmd_header));
1748 /* Extended infos are included at the end of events */
1749 nb_event = cmd_list_events(cmd_ctx->lsm.domain.type,
1750 cmd_ctx->session, cmd_ctx->lsm.u.list.channel_name,
1751 &events, &total_size);
1752
1753 if (nb_event < 0) {
1754 /* Return value is a negative lttng_error_code. */
1755 ret = -nb_event;
1756 goto error;
1757 }
1758
1759 cmd_header.nb_events = nb_event;
1760 ret = setup_lttng_msg(cmd_ctx, events, total_size,
1761 &cmd_header, sizeof(cmd_header));
1762 free(events);
1763
1764 if (ret < 0) {
1765 goto setup_error;
1766 }
1767
1768 ret = LTTNG_OK;
1769 break;
1770 }
1771 case LTTNG_LIST_SESSIONS:
1772 {
1773 unsigned int nr_sessions;
1774 void *sessions_payload;
1775 size_t payload_len;
1776
1777 session_lock_list();
1778 nr_sessions = lttng_sessions_count(
1779 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1780 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
1781
1782 payload_len = (sizeof(struct lttng_session) * nr_sessions) +
1783 (sizeof(struct lttng_session_extended) * nr_sessions);
1784 sessions_payload = zmalloc(payload_len);
1785
1786 if (!sessions_payload) {
1787 session_unlock_list();
1788 ret = -ENOMEM;
1789 goto setup_error;
1790 }
1791
1792 cmd_list_lttng_sessions(sessions_payload, nr_sessions,
1793 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1794 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
1795 session_unlock_list();
1796
1797 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, sessions_payload,
1798 payload_len);
1799 free(sessions_payload);
1800
1801 if (ret < 0) {
1802 goto setup_error;
1803 }
1804
1805 ret = LTTNG_OK;
1806 break;
1807 }
1808 case LTTNG_REGISTER_CONSUMER:
1809 {
1810 struct consumer_data *cdata;
1811
1812 switch (cmd_ctx->lsm.domain.type) {
1813 case LTTNG_DOMAIN_KERNEL:
1814 cdata = &kconsumer_data;
1815 break;
1816 default:
1817 ret = LTTNG_ERR_UND;
1818 goto error;
1819 }
1820
1821 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm.domain.type,
1822 cmd_ctx->lsm.u.reg.path, cdata);
1823 break;
1824 }
1825 case LTTNG_DATA_PENDING:
1826 {
1827 int pending_ret;
1828 uint8_t pending_ret_byte;
1829
1830 pending_ret = cmd_data_pending(cmd_ctx->session);
1831
1832 /*
1833 * FIXME
1834 *
1835 * This function may returns 0 or 1 to indicate whether or not
1836 * there is data pending. In case of error, it should return an
1837 * LTTNG_ERR code. However, some code paths may still return
1838 * a nondescript error code, which we handle by returning an
1839 * "unknown" error.
1840 */
1841 if (pending_ret == 0 || pending_ret == 1) {
1842 /*
1843 * ret will be set to LTTNG_OK at the end of
1844 * this function.
1845 */
1846 } else if (pending_ret < 0) {
1847 ret = LTTNG_ERR_UNK;
1848 goto setup_error;
1849 } else {
1850 ret = pending_ret;
1851 goto setup_error;
1852 }
1853
1854 pending_ret_byte = (uint8_t) pending_ret;
1855
1856 /* 1 byte to return whether or not data is pending */
1857 ret = setup_lttng_msg_no_cmd_header(cmd_ctx,
1858 &pending_ret_byte, 1);
1859
1860 if (ret < 0) {
1861 goto setup_error;
1862 }
1863
1864 ret = LTTNG_OK;
1865 break;
1866 }
1867 case LTTNG_SNAPSHOT_ADD_OUTPUT:
1868 {
1869 uint32_t snapshot_id;
1870 struct lttcomm_lttng_output_id reply;
1871
1872 ret = cmd_snapshot_add_output(cmd_ctx->session,
1873 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.snapshot_output.output),
1874 &snapshot_id);
1875 if (ret != LTTNG_OK) {
1876 goto error;
1877 }
1878 reply.id = snapshot_id;
1879
1880 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &reply,
1881 sizeof(reply));
1882 if (ret < 0) {
1883 goto setup_error;
1884 }
1885
1886 /* Copy output list into message payload */
1887 ret = LTTNG_OK;
1888 break;
1889 }
1890 case LTTNG_SNAPSHOT_DEL_OUTPUT:
1891 {
1892 ret = cmd_snapshot_del_output(cmd_ctx->session,
1893 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.snapshot_output.output));
1894 break;
1895 }
1896 case LTTNG_SNAPSHOT_LIST_OUTPUT:
1897 {
1898 ssize_t nb_output;
1899 struct lttng_snapshot_output *outputs = NULL;
1900
1901 nb_output = cmd_snapshot_list_outputs(cmd_ctx->session, &outputs);
1902 if (nb_output < 0) {
1903 ret = -nb_output;
1904 goto error;
1905 }
1906
1907 assert((nb_output > 0 && outputs) || nb_output == 0);
1908 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, outputs,
1909 nb_output * sizeof(struct lttng_snapshot_output));
1910 free(outputs);
1911
1912 if (ret < 0) {
1913 goto setup_error;
1914 }
1915
1916 ret = LTTNG_OK;
1917 break;
1918 }
1919 case LTTNG_SNAPSHOT_RECORD:
1920 {
1921 ret = cmd_snapshot_record(cmd_ctx->session,
1922 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.snapshot_record.output),
1923 cmd_ctx->lsm.u.snapshot_record.wait);
1924 break;
1925 }
1926 case LTTNG_CREATE_SESSION_EXT:
1927 {
1928 struct lttng_dynamic_buffer payload;
1929 struct lttng_session_descriptor *return_descriptor = NULL;
1930
1931 lttng_dynamic_buffer_init(&payload);
1932 ret = cmd_create_session(cmd_ctx, *sock, &return_descriptor);
1933 if (ret != LTTNG_OK) {
1934 goto error;
1935 }
1936
1937 ret = lttng_session_descriptor_serialize(return_descriptor,
1938 &payload);
1939 if (ret) {
1940 ERR("Failed to serialize session descriptor in reply to \"create session\" command");
1941 lttng_session_descriptor_destroy(return_descriptor);
1942 ret = LTTNG_ERR_NOMEM;
1943 goto error;
1944 }
1945 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, payload.data,
1946 payload.size);
1947 if (ret) {
1948 lttng_session_descriptor_destroy(return_descriptor);
1949 ret = LTTNG_ERR_NOMEM;
1950 goto error;
1951 }
1952 lttng_dynamic_buffer_reset(&payload);
1953 lttng_session_descriptor_destroy(return_descriptor);
1954 ret = LTTNG_OK;
1955 break;
1956 }
1957 case LTTNG_SAVE_SESSION:
1958 {
1959 ret = cmd_save_sessions(&cmd_ctx->lsm.u.save_session.attr,
1960 &cmd_ctx->creds);
1961 break;
1962 }
1963 case LTTNG_SET_SESSION_SHM_PATH:
1964 {
1965 ret = cmd_set_session_shm_path(cmd_ctx->session,
1966 cmd_ctx->lsm.u.set_shm_path.shm_path);
1967 break;
1968 }
1969 case LTTNG_REGENERATE_METADATA:
1970 {
1971 ret = cmd_regenerate_metadata(cmd_ctx->session);
1972 break;
1973 }
1974 case LTTNG_REGENERATE_STATEDUMP:
1975 {
1976 ret = cmd_regenerate_statedump(cmd_ctx->session);
1977 break;
1978 }
1979 case LTTNG_REGISTER_TRIGGER:
1980 {
1981 ret = cmd_register_trigger(cmd_ctx, *sock,
1982 notification_thread_handle);
1983 break;
1984 }
1985 case LTTNG_UNREGISTER_TRIGGER:
1986 {
1987 ret = cmd_unregister_trigger(cmd_ctx, *sock,
1988 notification_thread_handle);
1989 break;
1990 }
1991 case LTTNG_ROTATE_SESSION:
1992 {
1993 struct lttng_rotate_session_return rotate_return;
1994
1995 DBG("Client rotate session \"%s\"", cmd_ctx->session->name);
1996
1997 memset(&rotate_return, 0, sizeof(rotate_return));
1998 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
1999 DBG("Kernel tracer version is not compatible with the rotation feature");
2000 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
2001 goto error;
2002 }
2003
2004 ret = cmd_rotate_session(cmd_ctx->session, &rotate_return,
2005 false,
2006 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
2007 if (ret < 0) {
2008 ret = -ret;
2009 goto error;
2010 }
2011
2012 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &rotate_return,
2013 sizeof(rotate_return));
2014 if (ret < 0) {
2015 ret = -ret;
2016 goto error;
2017 }
2018
2019 ret = LTTNG_OK;
2020 break;
2021 }
2022 case LTTNG_ROTATION_GET_INFO:
2023 {
2024 struct lttng_rotation_get_info_return get_info_return;
2025
2026 memset(&get_info_return, 0, sizeof(get_info_return));
2027 ret = cmd_rotate_get_info(cmd_ctx->session, &get_info_return,
2028 cmd_ctx->lsm.u.get_rotation_info.rotation_id);
2029 if (ret < 0) {
2030 ret = -ret;
2031 goto error;
2032 }
2033
2034 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &get_info_return,
2035 sizeof(get_info_return));
2036 if (ret < 0) {
2037 ret = -ret;
2038 goto error;
2039 }
2040
2041 ret = LTTNG_OK;
2042 break;
2043 }
2044 case LTTNG_ROTATION_SET_SCHEDULE:
2045 {
2046 bool set_schedule;
2047 enum lttng_rotation_schedule_type schedule_type;
2048 uint64_t value;
2049
2050 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
2051 DBG("Kernel tracer version does not support session rotations");
2052 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
2053 goto error;
2054 }
2055
2056 set_schedule = cmd_ctx->lsm.u.rotation_set_schedule.set == 1;
2057 schedule_type = (enum lttng_rotation_schedule_type) cmd_ctx->lsm.u.rotation_set_schedule.type;
2058 value = cmd_ctx->lsm.u.rotation_set_schedule.value;
2059
2060 ret = cmd_rotation_set_schedule(cmd_ctx->session,
2061 set_schedule,
2062 schedule_type,
2063 value,
2064 notification_thread_handle);
2065 if (ret != LTTNG_OK) {
2066 goto error;
2067 }
2068
2069 break;
2070 }
2071 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
2072 {
2073 struct lttng_session_list_schedules_return schedules = {
2074 .periodic.set = !!cmd_ctx->session->rotate_timer_period,
2075 .periodic.value = cmd_ctx->session->rotate_timer_period,
2076 .size.set = !!cmd_ctx->session->rotate_size,
2077 .size.value = cmd_ctx->session->rotate_size,
2078 };
2079
2080 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &schedules,
2081 sizeof(schedules));
2082 if (ret < 0) {
2083 ret = -ret;
2084 goto error;
2085 }
2086
2087 ret = LTTNG_OK;
2088 break;
2089 }
2090 case LTTNG_CLEAR_SESSION:
2091 {
2092 ret = cmd_clear_session(cmd_ctx->session, sock);
2093 break;
2094 }
2095 default:
2096 ret = LTTNG_ERR_UND;
2097 break;
2098 }
2099
2100 error:
2101 if (cmd_ctx->reply_payload.buffer.size == 0) {
2102 DBG("Missing llm header, creating one.");
2103 if (setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0) < 0) {
2104 goto setup_error;
2105 }
2106 }
2107 /* Set return code */
2108 ((struct lttcomm_lttng_msg *) (cmd_ctx->reply_payload.buffer.data))->ret_code = ret;
2109 setup_error:
2110 if (cmd_ctx->session) {
2111 session_unlock(cmd_ctx->session);
2112 session_put(cmd_ctx->session);
2113 cmd_ctx->session = NULL;
2114 }
2115 if (need_tracing_session) {
2116 session_unlock_list();
2117 }
2118 init_setup_error:
2119 assert(!rcu_read_ongoing());
2120 return ret;
2121 }
2122
2123 static int create_client_sock(void)
2124 {
2125 int ret, client_sock;
2126 const mode_t old_umask = umask(0);
2127
2128 /* Create client tool unix socket */
2129 client_sock = lttcomm_create_unix_sock(config.client_unix_sock_path.value);
2130 if (client_sock < 0) {
2131 ERR("Create unix sock failed: %s", config.client_unix_sock_path.value);
2132 ret = -1;
2133 goto end;
2134 }
2135
2136 /* Set the cloexec flag */
2137 ret = utils_set_fd_cloexec(client_sock);
2138 if (ret < 0) {
2139 ERR("Unable to set CLOEXEC flag to the client Unix socket (fd: %d). "
2140 "Continuing but note that the consumer daemon will have a "
2141 "reference to this socket on exec()", client_sock);
2142 }
2143
2144 /* File permission MUST be 660 */
2145 ret = chmod(config.client_unix_sock_path.value, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
2146 if (ret < 0) {
2147 ERR("Set file permissions failed: %s",
2148 config.client_unix_sock_path.value);
2149 PERROR("chmod");
2150 (void) lttcomm_close_unix_sock(client_sock);
2151 ret = -1;
2152 goto end;
2153 }
2154 DBG("Created client socket (fd = %i)", client_sock);
2155 ret = client_sock;
2156 end:
2157 umask(old_umask);
2158 return ret;
2159 }
2160
2161 static void cleanup_client_thread(void *data)
2162 {
2163 struct lttng_pipe *quit_pipe = data;
2164
2165 lttng_pipe_destroy(quit_pipe);
2166 }
2167
2168 static void thread_init_cleanup(void *data)
2169 {
2170 set_thread_status(false);
2171 }
2172
2173 /*
2174 * This thread manage all clients request using the unix client socket for
2175 * communication.
2176 */
2177 static void *thread_manage_clients(void *data)
2178 {
2179 int sock = -1, ret, i, pollfd, err = -1;
2180 int sock_error;
2181 uint32_t revents, nb_fd;
2182 struct lttng_poll_event events;
2183 const int client_sock = thread_state.client_sock;
2184 struct lttng_pipe *quit_pipe = data;
2185 const int thread_quit_pipe_fd = lttng_pipe_get_readfd(quit_pipe);
2186 struct command_ctx cmd_ctx = {};
2187
2188 DBG("[thread] Manage client started");
2189
2190 lttng_payload_init(&cmd_ctx.reply_payload);
2191
2192 is_root = (getuid() == 0);
2193
2194 pthread_cleanup_push(thread_init_cleanup, NULL);
2195
2196 rcu_register_thread();
2197
2198 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_CMD);
2199
2200 health_code_update();
2201
2202 ret = lttcomm_listen_unix_sock(client_sock);
2203 if (ret < 0) {
2204 goto error_listen;
2205 }
2206
2207 /*
2208 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2209 * more will be added to this poll set.
2210 */
2211 ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
2212 if (ret < 0) {
2213 goto error_create_poll;
2214 }
2215
2216 /* Add the application registration socket */
2217 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
2218 if (ret < 0) {
2219 goto error;
2220 }
2221
2222 /* Add thread quit pipe */
2223 ret = lttng_poll_add(&events, thread_quit_pipe_fd, LPOLLIN | LPOLLERR);
2224 if (ret < 0) {
2225 goto error;
2226 }
2227
2228 /* Set state as running. */
2229 set_thread_status(true);
2230 pthread_cleanup_pop(0);
2231
2232 /* This testpoint is after we signal readiness to the parent. */
2233 if (testpoint(sessiond_thread_manage_clients)) {
2234 goto error;
2235 }
2236
2237 if (testpoint(sessiond_thread_manage_clients_before_loop)) {
2238 goto error;
2239 }
2240
2241 health_code_update();
2242
2243 while (1) {
2244 const struct cmd_completion_handler *cmd_completion_handler;
2245
2246 cmd_ctx.creds = (lttng_sock_cred) {
2247 .uid = UINT32_MAX,
2248 .gid = UINT32_MAX,
2249 };
2250 cmd_ctx.session = NULL;
2251 lttng_dynamic_buffer_set_size(&cmd_ctx.reply_payload.buffer, 0);
2252 lttng_dynamic_array_clear(&cmd_ctx.reply_payload._fds);
2253
2254 DBG("Accepting client command ...");
2255
2256 /* Inifinite blocking call, waiting for transmission */
2257 restart:
2258 health_poll_entry();
2259 ret = lttng_poll_wait(&events, -1);
2260 health_poll_exit();
2261 if (ret < 0) {
2262 /*
2263 * Restart interrupted system call.
2264 */
2265 if (errno == EINTR) {
2266 goto restart;
2267 }
2268 goto error;
2269 }
2270
2271 nb_fd = ret;
2272
2273 for (i = 0; i < nb_fd; i++) {
2274 revents = LTTNG_POLL_GETEV(&events, i);
2275 pollfd = LTTNG_POLL_GETFD(&events, i);
2276
2277 health_code_update();
2278
2279 if (pollfd == thread_quit_pipe_fd) {
2280 err = 0;
2281 goto exit;
2282 } else {
2283 /* Event on the registration socket */
2284 if (revents & LPOLLIN) {
2285 continue;
2286 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2287 ERR("Client socket poll error");
2288 goto error;
2289 } else {
2290 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
2291 goto error;
2292 }
2293 }
2294 }
2295
2296 DBG("Wait for client response");
2297
2298 health_code_update();
2299
2300 sock = lttcomm_accept_unix_sock(client_sock);
2301 if (sock < 0) {
2302 goto error;
2303 }
2304
2305 /*
2306 * Set the CLOEXEC flag. Return code is useless because either way, the
2307 * show must go on.
2308 */
2309 (void) utils_set_fd_cloexec(sock);
2310
2311 /* Set socket option for credentials retrieval */
2312 ret = lttcomm_setsockopt_creds_unix_sock(sock);
2313 if (ret < 0) {
2314 goto error;
2315 }
2316
2317 health_code_update();
2318
2319 /*
2320 * Data is received from the lttng client. The struct
2321 * lttcomm_session_msg (lsm) contains the command and data request of
2322 * the client.
2323 */
2324 DBG("Receiving data from client ...");
2325 ret = lttcomm_recv_creds_unix_sock(sock, &cmd_ctx.lsm,
2326 sizeof(struct lttcomm_session_msg), &cmd_ctx.creds);
2327 if (ret != sizeof(struct lttcomm_session_msg)) {
2328 DBG("Incomplete recv() from client... continuing");
2329 ret = close(sock);
2330 if (ret) {
2331 PERROR("close");
2332 }
2333 sock = -1;
2334 continue;
2335 }
2336
2337 health_code_update();
2338
2339 // TODO: Validate cmd_ctx including sanity check for
2340 // security purpose.
2341
2342 rcu_thread_online();
2343 /*
2344 * This function dispatch the work to the kernel or userspace tracer
2345 * libs and fill the lttcomm_lttng_msg data structure of all the needed
2346 * informations for the client. The command context struct contains
2347 * everything this function may needs.
2348 */
2349 ret = process_client_msg(&cmd_ctx, &sock, &sock_error);
2350 rcu_thread_offline();
2351 if (ret < 0) {
2352 if (sock >= 0) {
2353 ret = close(sock);
2354 if (ret) {
2355 PERROR("close");
2356 }
2357 }
2358 sock = -1;
2359 /*
2360 * TODO: Inform client somehow of the fatal error. At
2361 * this point, ret < 0 means that a zmalloc failed
2362 * (ENOMEM). Error detected but still accept
2363 * command, unless a socket error has been
2364 * detected.
2365 */
2366 continue;
2367 }
2368
2369 cmd_completion_handler = cmd_pop_completion_handler();
2370 if (cmd_completion_handler) {
2371 enum lttng_error_code completion_code;
2372
2373 completion_code = cmd_completion_handler->run(
2374 cmd_completion_handler->data);
2375 if (completion_code != LTTNG_OK) {
2376 continue;
2377 }
2378 }
2379
2380 health_code_update();
2381
2382 if (sock >= 0) {
2383 struct lttng_payload_view view =
2384 lttng_payload_view_from_payload(
2385 &cmd_ctx.reply_payload,
2386 0, -1);
2387 const struct lttcomm_lttng_msg *llm = (typeof(
2388 llm)) cmd_ctx.reply_payload.buffer.data;
2389
2390 assert(cmd_ctx.reply_payload.buffer.size >=
2391 sizeof(llm));
2392 assert(cmd_ctx.lttng_msg_size == cmd_ctx.reply_payload.buffer.size);
2393
2394 DBG("Sending response (size: %d, retcode: %s (%d))",
2395 cmd_ctx.lttng_msg_size,
2396 lttng_strerror(-llm->ret_code),
2397 llm->ret_code);
2398 ret = send_unix_sock(sock, &view);
2399 if (ret < 0) {
2400 ERR("Failed to send data back to client");
2401 }
2402
2403 /* End of transmission */
2404 ret = close(sock);
2405 if (ret) {
2406 PERROR("close");
2407 }
2408 }
2409 sock = -1;
2410
2411 health_code_update();
2412 }
2413
2414 exit:
2415 error:
2416 if (sock >= 0) {
2417 ret = close(sock);
2418 if (ret) {
2419 PERROR("close");
2420 }
2421 }
2422
2423 lttng_poll_clean(&events);
2424
2425 error_listen:
2426 error_create_poll:
2427 unlink(config.client_unix_sock_path.value);
2428 ret = close(client_sock);
2429 if (ret) {
2430 PERROR("close");
2431 }
2432
2433 if (err) {
2434 health_error();
2435 ERR("Health error occurred in %s", __func__);
2436 }
2437
2438 health_unregister(health_sessiond);
2439
2440 DBG("Client thread dying");
2441 lttng_payload_reset(&cmd_ctx.reply_payload);
2442 rcu_unregister_thread();
2443 return NULL;
2444 }
2445
2446 static
2447 bool shutdown_client_thread(void *thread_data)
2448 {
2449 struct lttng_pipe *client_quit_pipe = thread_data;
2450 const int write_fd = lttng_pipe_get_writefd(client_quit_pipe);
2451
2452 return notify_thread_pipe(write_fd) == 1;
2453 }
2454
2455 struct lttng_thread *launch_client_thread(void)
2456 {
2457 bool thread_running;
2458 struct lttng_pipe *client_quit_pipe;
2459 struct lttng_thread *thread = NULL;
2460 int client_sock_fd = -1;
2461
2462 sem_init(&thread_state.ready, 0, 0);
2463 client_quit_pipe = lttng_pipe_open(FD_CLOEXEC);
2464 if (!client_quit_pipe) {
2465 goto error;
2466 }
2467
2468 client_sock_fd = create_client_sock();
2469 if (client_sock_fd < 0) {
2470 goto error;
2471 }
2472
2473 thread_state.client_sock = client_sock_fd;
2474 thread = lttng_thread_create("Client management",
2475 thread_manage_clients,
2476 shutdown_client_thread,
2477 cleanup_client_thread,
2478 client_quit_pipe);
2479 if (!thread) {
2480 goto error;
2481 }
2482 /* The client thread now owns the client sock fd and the quit pipe. */
2483 client_sock_fd = -1;
2484 client_quit_pipe = NULL;
2485
2486 /*
2487 * This thread is part of the threads that need to be fully
2488 * initialized before the session daemon is marked as "ready".
2489 */
2490 thread_running = wait_thread_status();
2491 if (!thread_running) {
2492 goto error;
2493 }
2494 return thread;
2495 error:
2496 if (client_sock_fd >= 0) {
2497 if (close(client_sock_fd)) {
2498 PERROR("Failed to close client socket");
2499 }
2500 }
2501 lttng_thread_put(thread);
2502 cleanup_client_thread(client_quit_pipe);
2503 return NULL;
2504 }
LTTng tools - Deliverables
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