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sessiond: client commands: print command enum as a string
[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/fd-handle.h"
17 #include "common/sessiond-comm/sessiond-comm.h"
18 #include "common/payload.h"
19 #include "common/payload-view.h"
20 #include "lttng/lttng-error.h"
21 #include "lttng/tracker.h"
22 #include <common/compat/getenv.h>
23 #include <common/tracker.h>
24 #include <common/unix.h>
25 #include <common/utils.h>
26 #include <lttng/event-internal.h>
27 #include <lttng/session-descriptor-internal.h>
28 #include <lttng/session-internal.h>
29 #include <lttng/userspace-probe-internal.h>
30 #include <pthread.h>
31 #include <signal.h>
32 #include <stddef.h>
33 #include <sys/stat.h>
34 #include <unistd.h>
35
36 #include "client.h"
37 #include "lttng-sessiond.h"
38 #include "cmd.h"
39 #include "kernel.h"
40 #include "save.h"
41 #include "health-sessiond.h"
42 #include "testpoint.h"
43 #include "utils.h"
44 #include "manage-consumer.h"
45 #include "clear.h"
46
47 static bool is_root;
48
49 static struct thread_state {
50 sem_t ready;
51 bool running;
52 int client_sock;
53 } thread_state;
54
55 static void set_thread_status(bool running)
56 {
57 DBG("Marking client thread's state as %s", running ? "running" : "error");
58 thread_state.running = running;
59 sem_post(&thread_state.ready);
60 }
61
62 static bool wait_thread_status(void)
63 {
64 DBG("Waiting for client thread to be ready");
65 sem_wait(&thread_state.ready);
66 if (thread_state.running) {
67 DBG("Client thread is ready");
68 } else {
69 ERR("Initialization of client thread failed");
70 }
71
72 return thread_state.running;
73 }
74
75 /*
76 * Setup the outgoing data buffer for the response (llm) by allocating the
77 * right amount of memory and copying the original information from the lsm
78 * structure.
79 *
80 * Return 0 on success, negative value on error.
81 */
82 static int setup_lttng_msg(struct command_ctx *cmd_ctx,
83 const void *payload_buf, size_t payload_len,
84 const void *cmd_header_buf, size_t cmd_header_len)
85 {
86 int ret = 0;
87 const size_t header_len = sizeof(struct lttcomm_lttng_msg);
88 const size_t total_msg_size = header_len + cmd_header_len + payload_len;
89 const struct lttcomm_lttng_msg llm = {
90 .cmd_type = cmd_ctx->lsm.cmd_type,
91 .pid = cmd_ctx->lsm.domain.attr.pid,
92 .cmd_header_size = cmd_header_len,
93 .data_size = payload_len,
94 };
95
96 ret = lttng_dynamic_buffer_set_size(&cmd_ctx->reply_payload.buffer, 0);
97 if (ret) {
98 goto end;
99 }
100
101 lttng_dynamic_pointer_array_clear(&cmd_ctx->reply_payload._fd_handles);
102
103 cmd_ctx->lttng_msg_size = total_msg_size;
104
105 /* Append reply header. */
106 ret = lttng_dynamic_buffer_append(
107 &cmd_ctx->reply_payload.buffer, &llm, sizeof(llm));
108 if (ret) {
109 goto end;
110 }
111
112 /* Append command header. */
113 if (cmd_header_len) {
114 ret = lttng_dynamic_buffer_append(
115 &cmd_ctx->reply_payload.buffer, cmd_header_buf,
116 cmd_header_len);
117 if (ret) {
118 goto end;
119 }
120 }
121
122 /* Append payload. */
123 if (payload_len) {
124 ret = lttng_dynamic_buffer_append(
125 &cmd_ctx->reply_payload.buffer, payload_buf,
126 payload_len);
127 if (ret) {
128 goto end;
129 }
130 }
131
132 end:
133 return ret;
134 }
135
136 static int setup_empty_lttng_msg(struct command_ctx *cmd_ctx)
137 {
138 int ret;
139 const struct lttcomm_lttng_msg llm = {};
140
141 ret = lttng_dynamic_buffer_set_size(&cmd_ctx->reply_payload.buffer, 0);
142 if (ret) {
143 goto end;
144 }
145
146 /* Append place-holder reply header. */
147 ret = lttng_dynamic_buffer_append(
148 &cmd_ctx->reply_payload.buffer, &llm, sizeof(llm));
149 if (ret) {
150 goto end;
151 }
152
153 cmd_ctx->lttng_msg_size = sizeof(llm);
154 end:
155 return ret;
156 }
157
158 static void update_lttng_msg(struct command_ctx *cmd_ctx, size_t cmd_header_len,
159 size_t payload_len)
160 {
161 const size_t header_len = sizeof(struct lttcomm_lttng_msg);
162 const size_t total_msg_size = header_len + cmd_header_len + payload_len;
163 const struct lttcomm_lttng_msg llm = {
164 .cmd_type = cmd_ctx->lsm.cmd_type,
165 .pid = cmd_ctx->lsm.domain.attr.pid,
166 .cmd_header_size = cmd_header_len,
167 .data_size = payload_len,
168 };
169 struct lttcomm_lttng_msg *p_llm;
170
171 assert(cmd_ctx->reply_payload.buffer.size >= sizeof(llm));
172
173 p_llm = (typeof(p_llm)) cmd_ctx->reply_payload.buffer.data;
174
175 /* Update existing header. */
176 memcpy(p_llm, &llm, sizeof(llm));
177
178 cmd_ctx->lttng_msg_size = total_msg_size;
179 }
180
181 /*
182 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
183 * exec or it will fail.
184 */
185 static int spawn_consumer_thread(struct consumer_data *consumer_data)
186 {
187 return launch_consumer_management_thread(consumer_data) ? 0 : -1;
188 }
189
190 /*
191 * Fork and exec a consumer daemon (consumerd).
192 *
193 * Return pid if successful else -1.
194 */
195 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
196 {
197 int ret;
198 pid_t pid;
199 const char *consumer_to_use;
200 const char *verbosity;
201 struct stat st;
202
203 DBG("Spawning consumerd");
204
205 pid = fork();
206 if (pid == 0) {
207 /*
208 * Exec consumerd.
209 */
210 if (config.verbose_consumer) {
211 verbosity = "--verbose";
212 } else if (lttng_opt_quiet) {
213 verbosity = "--quiet";
214 } else {
215 verbosity = "";
216 }
217
218 switch (consumer_data->type) {
219 case LTTNG_CONSUMER_KERNEL:
220 /*
221 * Find out which consumerd to execute. We will first try the
222 * 64-bit path, then the sessiond's installation directory, and
223 * fallback on the 32-bit one,
224 */
225 DBG3("Looking for a kernel consumer at these locations:");
226 DBG3(" 1) %s", config.consumerd64_bin_path.value ? : "NULL");
227 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, DEFAULT_CONSUMERD_FILE);
228 DBG3(" 3) %s", config.consumerd32_bin_path.value ? : "NULL");
229 if (stat(config.consumerd64_bin_path.value, &st) == 0) {
230 DBG3("Found location #1");
231 consumer_to_use = config.consumerd64_bin_path.value;
232 } else if (stat(INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE, &st) == 0) {
233 DBG3("Found location #2");
234 consumer_to_use = INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE;
235 } else if (config.consumerd32_bin_path.value &&
236 stat(config.consumerd32_bin_path.value, &st) == 0) {
237 DBG3("Found location #3");
238 consumer_to_use = config.consumerd32_bin_path.value;
239 } else {
240 DBG("Could not find any valid consumerd executable");
241 ret = -EINVAL;
242 goto error;
243 }
244 DBG("Using kernel consumer at: %s", consumer_to_use);
245 (void) execl(consumer_to_use,
246 "lttng-consumerd", verbosity, "-k",
247 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
248 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
249 "--group", config.tracing_group_name.value,
250 NULL);
251 break;
252 case LTTNG_CONSUMER64_UST:
253 {
254 if (config.consumerd64_lib_dir.value) {
255 const char *tmp;
256 size_t tmplen;
257 char *tmpnew;
258
259 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
260 if (!tmp) {
261 tmp = "";
262 }
263 tmplen = strlen(config.consumerd64_lib_dir.value) + 1 /* : */ + strlen(tmp);
264 tmpnew = zmalloc(tmplen + 1 /* \0 */);
265 if (!tmpnew) {
266 ret = -ENOMEM;
267 goto error;
268 }
269 strcat(tmpnew, config.consumerd64_lib_dir.value);
270 if (tmp[0] != '\0') {
271 strcat(tmpnew, ":");
272 strcat(tmpnew, tmp);
273 }
274 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
275 free(tmpnew);
276 if (ret) {
277 ret = -errno;
278 goto error;
279 }
280 }
281 DBG("Using 64-bit UST consumer at: %s", config.consumerd64_bin_path.value);
282 (void) execl(config.consumerd64_bin_path.value, "lttng-consumerd", verbosity, "-u",
283 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
284 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
285 "--group", config.tracing_group_name.value,
286 NULL);
287 break;
288 }
289 case LTTNG_CONSUMER32_UST:
290 {
291 if (config.consumerd32_lib_dir.value) {
292 const char *tmp;
293 size_t tmplen;
294 char *tmpnew;
295
296 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
297 if (!tmp) {
298 tmp = "";
299 }
300 tmplen = strlen(config.consumerd32_lib_dir.value) + 1 /* : */ + strlen(tmp);
301 tmpnew = zmalloc(tmplen + 1 /* \0 */);
302 if (!tmpnew) {
303 ret = -ENOMEM;
304 goto error;
305 }
306 strcat(tmpnew, config.consumerd32_lib_dir.value);
307 if (tmp[0] != '\0') {
308 strcat(tmpnew, ":");
309 strcat(tmpnew, tmp);
310 }
311 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
312 free(tmpnew);
313 if (ret) {
314 ret = -errno;
315 goto error;
316 }
317 }
318 DBG("Using 32-bit UST consumer at: %s", config.consumerd32_bin_path.value);
319 (void) execl(config.consumerd32_bin_path.value, "lttng-consumerd", verbosity, "-u",
320 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
321 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
322 "--group", config.tracing_group_name.value,
323 NULL);
324 break;
325 }
326 default:
327 ERR("unknown consumer type");
328 errno = 0;
329 }
330 if (errno != 0) {
331 PERROR("Consumer execl()");
332 }
333 /* Reaching this point, we got a failure on our execl(). */
334 exit(EXIT_FAILURE);
335 } else if (pid > 0) {
336 ret = pid;
337 } else {
338 PERROR("start consumer fork");
339 ret = -errno;
340 }
341 error:
342 return ret;
343 }
344
345 /*
346 * Spawn the consumerd daemon and session daemon thread.
347 */
348 static int start_consumerd(struct consumer_data *consumer_data)
349 {
350 int ret;
351
352 /*
353 * Set the listen() state on the socket since there is a possible race
354 * between the exec() of the consumer daemon and this call if place in the
355 * consumer thread. See bug #366 for more details.
356 */
357 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
358 if (ret < 0) {
359 goto error;
360 }
361
362 pthread_mutex_lock(&consumer_data->pid_mutex);
363 if (consumer_data->pid != 0) {
364 pthread_mutex_unlock(&consumer_data->pid_mutex);
365 goto end;
366 }
367
368 ret = spawn_consumerd(consumer_data);
369 if (ret < 0) {
370 ERR("Spawning consumerd failed");
371 pthread_mutex_unlock(&consumer_data->pid_mutex);
372 goto error;
373 }
374
375 /* Setting up the consumer_data pid */
376 consumer_data->pid = ret;
377 DBG2("Consumer pid %d", consumer_data->pid);
378 pthread_mutex_unlock(&consumer_data->pid_mutex);
379
380 DBG2("Spawning consumer control thread");
381 ret = spawn_consumer_thread(consumer_data);
382 if (ret < 0) {
383 ERR("Fatal error spawning consumer control thread");
384 goto error;
385 }
386
387 end:
388 return 0;
389
390 error:
391 /* Cleanup already created sockets on error. */
392 if (consumer_data->err_sock >= 0) {
393 int err;
394
395 err = close(consumer_data->err_sock);
396 if (err < 0) {
397 PERROR("close consumer data error socket");
398 }
399 }
400 return ret;
401 }
402
403 /*
404 * Copy consumer output from the tracing session to the domain session. The
405 * function also applies the right modification on a per domain basis for the
406 * trace files destination directory.
407 *
408 * Should *NOT* be called with RCU read-side lock held.
409 */
410 static int copy_session_consumer(int domain, struct ltt_session *session)
411 {
412 int ret;
413 const char *dir_name;
414 struct consumer_output *consumer;
415
416 assert(session);
417 assert(session->consumer);
418
419 switch (domain) {
420 case LTTNG_DOMAIN_KERNEL:
421 DBG3("Copying tracing session consumer output in kernel session");
422 /*
423 * XXX: We should audit the session creation and what this function
424 * does "extra" in order to avoid a destroy since this function is used
425 * in the domain session creation (kernel and ust) only. Same for UST
426 * domain.
427 */
428 if (session->kernel_session->consumer) {
429 consumer_output_put(session->kernel_session->consumer);
430 }
431 session->kernel_session->consumer =
432 consumer_copy_output(session->consumer);
433 /* Ease our life a bit for the next part */
434 consumer = session->kernel_session->consumer;
435 dir_name = DEFAULT_KERNEL_TRACE_DIR;
436 break;
437 case LTTNG_DOMAIN_JUL:
438 case LTTNG_DOMAIN_LOG4J:
439 case LTTNG_DOMAIN_PYTHON:
440 case LTTNG_DOMAIN_UST:
441 DBG3("Copying tracing session consumer output in UST session");
442 if (session->ust_session->consumer) {
443 consumer_output_put(session->ust_session->consumer);
444 }
445 session->ust_session->consumer =
446 consumer_copy_output(session->consumer);
447 /* Ease our life a bit for the next part */
448 consumer = session->ust_session->consumer;
449 dir_name = DEFAULT_UST_TRACE_DIR;
450 break;
451 default:
452 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
453 goto error;
454 }
455
456 /* Append correct directory to subdir */
457 ret = lttng_strncpy(consumer->domain_subdir, dir_name,
458 sizeof(consumer->domain_subdir));
459 if (ret) {
460 ret = LTTNG_ERR_UNK;
461 goto error;
462 }
463 DBG3("Copy session consumer subdir %s", consumer->domain_subdir);
464 ret = LTTNG_OK;
465
466 error:
467 return ret;
468 }
469
470 /*
471 * Create an UST session and add it to the session ust list.
472 *
473 * Should *NOT* be called with RCU read-side lock held.
474 */
475 static int create_ust_session(struct ltt_session *session,
476 const struct lttng_domain *domain)
477 {
478 int ret;
479 struct ltt_ust_session *lus = NULL;
480
481 assert(session);
482 assert(domain);
483 assert(session->consumer);
484
485 switch (domain->type) {
486 case LTTNG_DOMAIN_JUL:
487 case LTTNG_DOMAIN_LOG4J:
488 case LTTNG_DOMAIN_PYTHON:
489 case LTTNG_DOMAIN_UST:
490 break;
491 default:
492 ERR("Unknown UST domain on create session %d", domain->type);
493 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
494 goto error;
495 }
496
497 DBG("Creating UST session");
498
499 lus = trace_ust_create_session(session->id);
500 if (lus == NULL) {
501 ret = LTTNG_ERR_UST_SESS_FAIL;
502 goto error;
503 }
504
505 lus->uid = session->uid;
506 lus->gid = session->gid;
507 lus->output_traces = session->output_traces;
508 lus->snapshot_mode = session->snapshot_mode;
509 lus->live_timer_interval = session->live_timer;
510 session->ust_session = lus;
511 if (session->shm_path[0]) {
512 strncpy(lus->root_shm_path, session->shm_path,
513 sizeof(lus->root_shm_path));
514 lus->root_shm_path[sizeof(lus->root_shm_path) - 1] = '\0';
515 strncpy(lus->shm_path, session->shm_path,
516 sizeof(lus->shm_path));
517 lus->shm_path[sizeof(lus->shm_path) - 1] = '\0';
518 strncat(lus->shm_path, "/ust",
519 sizeof(lus->shm_path) - strlen(lus->shm_path) - 1);
520 }
521 /* Copy session output to the newly created UST session */
522 ret = copy_session_consumer(domain->type, session);
523 if (ret != LTTNG_OK) {
524 goto error;
525 }
526
527 return LTTNG_OK;
528
529 error:
530 free(lus);
531 session->ust_session = NULL;
532 return ret;
533 }
534
535 /*
536 * Create a kernel tracer session then create the default channel.
537 */
538 static int create_kernel_session(struct ltt_session *session)
539 {
540 int ret;
541
542 DBG("Creating kernel session");
543
544 ret = kernel_create_session(session);
545 if (ret < 0) {
546 ret = LTTNG_ERR_KERN_SESS_FAIL;
547 goto error_create;
548 }
549
550 /* Code flow safety */
551 assert(session->kernel_session);
552
553 /* Copy session output to the newly created Kernel session */
554 ret = copy_session_consumer(LTTNG_DOMAIN_KERNEL, session);
555 if (ret != LTTNG_OK) {
556 goto error;
557 }
558
559 session->kernel_session->uid = session->uid;
560 session->kernel_session->gid = session->gid;
561 session->kernel_session->output_traces = session->output_traces;
562 session->kernel_session->snapshot_mode = session->snapshot_mode;
563 session->kernel_session->is_live_session = session->live_timer != 0;
564
565 return LTTNG_OK;
566
567 error:
568 trace_kernel_destroy_session(session->kernel_session);
569 session->kernel_session = NULL;
570 error_create:
571 return ret;
572 }
573
574 /*
575 * Count number of session permitted by uid/gid.
576 */
577 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
578 {
579 unsigned int i = 0;
580 struct ltt_session *session;
581 const struct ltt_session_list *session_list = session_get_list();
582
583 DBG("Counting number of available session for UID %d", uid);
584 cds_list_for_each_entry(session, &session_list->head, list) {
585 if (!session_get(session)) {
586 continue;
587 }
588 session_lock(session);
589 /* Only count the sessions the user can control. */
590 if (session_access_ok(session, uid) &&
591 !session->destroyed) {
592 i++;
593 }
594 session_unlock(session);
595 session_put(session);
596 }
597 return i;
598 }
599
600 static int receive_userspace_probe(struct command_ctx *cmd_ctx, int sock,
601 int *sock_error, struct lttng_event *event)
602 {
603 int fd = -1, ret;
604 struct lttng_userspace_probe_location *probe_location;
605 struct lttng_payload probe_location_payload;
606 struct fd_handle *handle = NULL;
607
608 /*
609 * Create a payload to store the serialized version of the probe
610 * location.
611 */
612 lttng_payload_init(&probe_location_payload);
613
614 ret = lttng_dynamic_buffer_set_size(&probe_location_payload.buffer,
615 cmd_ctx->lsm.u.enable.userspace_probe_location_len);
616 if (ret) {
617 ret = LTTNG_ERR_NOMEM;
618 goto error;
619 }
620
621 /*
622 * Receive the probe location.
623 */
624 ret = lttcomm_recv_unix_sock(sock, probe_location_payload.buffer.data,
625 probe_location_payload.buffer.size);
626 if (ret <= 0) {
627 DBG("Nothing recv() from client var len data... continuing");
628 *sock_error = 1;
629 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
630 goto error;
631 }
632
633 /*
634 * Receive the file descriptor to the target binary from the client.
635 */
636 DBG("Receiving userspace probe target FD from client ...");
637 ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1);
638 if (ret <= 0) {
639 DBG("Nothing recv() from client userspace probe fd... continuing");
640 *sock_error = 1;
641 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
642 goto error;
643 }
644
645 handle = fd_handle_create(fd);
646 if (!handle) {
647 ret = LTTNG_ERR_NOMEM;
648 goto error;
649 }
650
651 /* Transferred to the handle. */
652 fd = -1;
653
654 ret = lttng_payload_push_fd_handle(&probe_location_payload, handle);
655 if (ret) {
656 ERR("Failed to add userspace probe file descriptor to payload");
657 ret = LTTNG_ERR_NOMEM;
658 goto error;
659 }
660
661 fd_handle_put(handle);
662 handle = NULL;
663
664 {
665 struct lttng_payload_view view = lttng_payload_view_from_payload(
666 &probe_location_payload, 0, -1);
667
668 /* Extract the probe location from the serialized version. */
669 ret = lttng_userspace_probe_location_create_from_payload(
670 &view, &probe_location);
671 }
672 if (ret < 0) {
673 WARN("Failed to create a userspace probe location from the received buffer");
674 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
675 goto error;
676 }
677
678 /* Attach the probe location to the event. */
679 ret = lttng_event_set_userspace_probe_location(event, probe_location);
680 if (ret) {
681 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
682 goto error;
683 }
684
685 error:
686 if (fd >= 0) {
687 if (close(fd)) {
688 PERROR("Failed to close userspace probe location binary fd");
689 }
690 }
691
692 fd_handle_put(handle);
693 lttng_payload_reset(&probe_location_payload);
694 return ret;
695 }
696
697 static enum lttng_error_code receive_lttng_trigger(struct command_ctx *cmd_ctx,
698 int sock,
699 int *sock_error,
700 struct lttng_trigger **_trigger)
701 {
702 int ret;
703 size_t trigger_len;
704 ssize_t sock_recv_len;
705 enum lttng_error_code ret_code;
706 struct lttng_payload trigger_payload;
707 struct lttng_trigger *trigger;
708
709 lttng_payload_init(&trigger_payload);
710 trigger_len = (size_t) cmd_ctx->lsm.u.trigger.length;
711 ret = lttng_dynamic_buffer_set_size(
712 &trigger_payload.buffer, trigger_len);
713 if (ret) {
714 ret_code = LTTNG_ERR_NOMEM;
715 goto end;
716 }
717
718 sock_recv_len = lttcomm_recv_unix_sock(
719 sock, trigger_payload.buffer.data, trigger_len);
720 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
721 ERR("Failed to receive trigger in command payload");
722 *sock_error = 1;
723 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
724 goto end;
725 }
726
727 /* Receive fds, if any. */
728 if (cmd_ctx->lsm.fd_count > 0) {
729 sock_recv_len = lttcomm_recv_payload_fds_unix_sock(
730 sock, cmd_ctx->lsm.fd_count, &trigger_payload);
731 if (sock_recv_len > 0 &&
732 sock_recv_len != cmd_ctx->lsm.fd_count * sizeof(int)) {
733 ERR("Failed to receive all file descriptors for trigger in command payload: expected fd count = %u, ret = %d",
734 cmd_ctx->lsm.fd_count, (int) ret);
735 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
736 *sock_error = 1;
737 goto end;
738 } else if (sock_recv_len <= 0) {
739 ERR("Failed to receive file descriptors for trigger in command payload: expected fd count = %u, ret = %d",
740 cmd_ctx->lsm.fd_count, (int) ret);
741 ret_code = LTTNG_ERR_FATAL;
742 *sock_error = 1;
743 goto end;
744 }
745 }
746
747 /* Deserialize trigger. */
748 {
749 struct lttng_payload_view view =
750 lttng_payload_view_from_payload(
751 &trigger_payload, 0, -1);
752
753 if (lttng_trigger_create_from_payload(&view, &trigger) !=
754 trigger_len) {
755 ERR("Invalid trigger received as part of command payload");
756 ret_code = LTTNG_ERR_INVALID_TRIGGER;
757 goto end;
758 }
759 }
760
761 *_trigger = trigger;
762 ret_code = LTTNG_OK;
763
764 end:
765 return ret_code;
766 }
767
768 /*
769 * Version of setup_lttng_msg() without command header.
770 */
771 static int setup_lttng_msg_no_cmd_header(struct command_ctx *cmd_ctx,
772 void *payload_buf, size_t payload_len)
773 {
774 return setup_lttng_msg(cmd_ctx, payload_buf, payload_len, NULL, 0);
775 }
776
777 /*
778 * Check if the current kernel tracer supports the session rotation feature.
779 * Return 1 if it does, 0 otherwise.
780 */
781 static int check_rotate_compatible(void)
782 {
783 int ret = 1;
784
785 if (kernel_tracer_version.major != 2 || kernel_tracer_version.minor < 11) {
786 DBG("Kernel tracer version is not compatible with the rotation feature");
787 ret = 0;
788 }
789
790 return ret;
791 }
792
793 /*
794 * Send data on a unix socket using the liblttsessiondcomm API.
795 *
796 * Return lttcomm error code.
797 */
798 static int send_unix_sock(int sock, struct lttng_payload_view *view)
799 {
800 int ret;
801 const int fd_count = lttng_payload_view_get_fd_handle_count(view);
802
803 /* Check valid length */
804 if (view->buffer.size == 0) {
805 ret = -1;
806 goto end;
807 }
808
809 ret = lttcomm_send_unix_sock(
810 sock, view->buffer.data, view->buffer.size);
811 if (ret < 0) {
812 goto end;
813 }
814
815 if (fd_count > 0) {
816 ret = lttcomm_send_payload_view_fds_unix_sock(sock, view);
817 if (ret < 0) {
818 goto end;
819 }
820 }
821
822 end:
823 return ret;
824 }
825
826 /*
827 * Process the command requested by the lttng client within the command
828 * context structure. This function make sure that the return structure (llm)
829 * is set and ready for transmission before returning.
830 *
831 * Return any error encountered or 0 for success.
832 *
833 * "sock" is only used for special-case var. len data.
834 * A command may assume the ownership of the socket, in which case its value
835 * should be set to -1.
836 *
837 * Should *NOT* be called with RCU read-side lock held.
838 */
839 static int process_client_msg(struct command_ctx *cmd_ctx, int *sock,
840 int *sock_error)
841 {
842 int ret = LTTNG_OK;
843 bool need_tracing_session = true;
844 bool need_domain;
845 bool need_consumerd;
846
847 DBG("Processing client command '%s\' (%d)",
848 lttcomm_sessiond_command_str(cmd_ctx->lsm.cmd_type),
849 cmd_ctx->lsm.cmd_type);
850
851 assert(!rcu_read_ongoing());
852
853 *sock_error = 0;
854
855 switch (cmd_ctx->lsm.cmd_type) {
856 case LTTNG_CREATE_SESSION_EXT:
857 case LTTNG_DESTROY_SESSION:
858 case LTTNG_LIST_SESSIONS:
859 case LTTNG_LIST_DOMAINS:
860 case LTTNG_START_TRACE:
861 case LTTNG_STOP_TRACE:
862 case LTTNG_DATA_PENDING:
863 case LTTNG_SNAPSHOT_ADD_OUTPUT:
864 case LTTNG_SNAPSHOT_DEL_OUTPUT:
865 case LTTNG_SNAPSHOT_LIST_OUTPUT:
866 case LTTNG_SNAPSHOT_RECORD:
867 case LTTNG_SAVE_SESSION:
868 case LTTNG_SET_SESSION_SHM_PATH:
869 case LTTNG_REGENERATE_METADATA:
870 case LTTNG_REGENERATE_STATEDUMP:
871 case LTTNG_ROTATE_SESSION:
872 case LTTNG_ROTATION_GET_INFO:
873 case LTTNG_ROTATION_SET_SCHEDULE:
874 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
875 case LTTNG_CLEAR_SESSION:
876 case LTTNG_LIST_TRIGGERS:
877 need_domain = false;
878 break;
879 default:
880 need_domain = true;
881 }
882
883 /* Needs a functioning consumerd? */
884 switch (cmd_ctx->lsm.cmd_type) {
885 case LTTNG_REGISTER_TRIGGER:
886 case LTTNG_UNREGISTER_TRIGGER:
887 need_consumerd = false;
888 break;
889 default:
890 need_consumerd = true;
891 break;
892 }
893
894 if (config.no_kernel && need_domain
895 && cmd_ctx->lsm.domain.type == LTTNG_DOMAIN_KERNEL) {
896 if (!is_root) {
897 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
898 } else {
899 ret = LTTNG_ERR_KERN_NA;
900 }
901 goto error;
902 }
903
904 /* Deny register consumer if we already have a spawned consumer. */
905 if (cmd_ctx->lsm.cmd_type == LTTNG_REGISTER_CONSUMER) {
906 pthread_mutex_lock(&kconsumer_data.pid_mutex);
907 if (kconsumer_data.pid > 0) {
908 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
909 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
910 goto error;
911 }
912 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
913 }
914
915 /*
916 * Check for command that don't needs to allocate a returned payload. We do
917 * this here so we don't have to make the call for no payload at each
918 * command.
919 */
920 switch(cmd_ctx->lsm.cmd_type) {
921 case LTTNG_LIST_SESSIONS:
922 case LTTNG_LIST_TRACEPOINTS:
923 case LTTNG_LIST_TRACEPOINT_FIELDS:
924 case LTTNG_LIST_DOMAINS:
925 case LTTNG_LIST_CHANNELS:
926 case LTTNG_LIST_EVENTS:
927 case LTTNG_LIST_SYSCALLS:
928 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
929 case LTTNG_PROCESS_ATTR_TRACKER_GET_POLICY:
930 case LTTNG_PROCESS_ATTR_TRACKER_GET_INCLUSION_SET:
931 case LTTNG_DATA_PENDING:
932 case LTTNG_ROTATE_SESSION:
933 case LTTNG_ROTATION_GET_INFO:
934 case LTTNG_REGISTER_TRIGGER:
935 case LTTNG_LIST_TRIGGERS:
936 break;
937 default:
938 /* Setup lttng message with no payload */
939 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0);
940 if (ret < 0) {
941 /* This label does not try to unlock the session */
942 goto init_setup_error;
943 }
944 }
945
946 /* Commands that DO NOT need a session. */
947 switch (cmd_ctx->lsm.cmd_type) {
948 case LTTNG_CREATE_SESSION_EXT:
949 case LTTNG_LIST_SESSIONS:
950 case LTTNG_LIST_TRACEPOINTS:
951 case LTTNG_LIST_SYSCALLS:
952 case LTTNG_LIST_TRACEPOINT_FIELDS:
953 case LTTNG_SAVE_SESSION:
954 case LTTNG_REGISTER_TRIGGER:
955 case LTTNG_UNREGISTER_TRIGGER:
956 case LTTNG_LIST_TRIGGERS:
957 need_tracing_session = false;
958 break;
959 default:
960 DBG("Getting session %s by name", cmd_ctx->lsm.session.name);
961 /*
962 * We keep the session list lock across _all_ commands
963 * for now, because the per-session lock does not
964 * handle teardown properly.
965 */
966 session_lock_list();
967 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm.session.name);
968 if (cmd_ctx->session == NULL) {
969 ret = LTTNG_ERR_SESS_NOT_FOUND;
970 goto error;
971 } else {
972 /* Acquire lock for the session */
973 session_lock(cmd_ctx->session);
974 }
975 break;
976 }
977
978 /*
979 * Commands that need a valid session but should NOT create one if none
980 * exists. Instead of creating one and destroying it when the command is
981 * handled, process that right before so we save some round trip in useless
982 * code path.
983 */
984 switch (cmd_ctx->lsm.cmd_type) {
985 case LTTNG_DISABLE_CHANNEL:
986 case LTTNG_DISABLE_EVENT:
987 switch (cmd_ctx->lsm.domain.type) {
988 case LTTNG_DOMAIN_KERNEL:
989 if (!cmd_ctx->session->kernel_session) {
990 ret = LTTNG_ERR_NO_CHANNEL;
991 goto error;
992 }
993 break;
994 case LTTNG_DOMAIN_JUL:
995 case LTTNG_DOMAIN_LOG4J:
996 case LTTNG_DOMAIN_PYTHON:
997 case LTTNG_DOMAIN_UST:
998 if (!cmd_ctx->session->ust_session) {
999 ret = LTTNG_ERR_NO_CHANNEL;
1000 goto error;
1001 }
1002 break;
1003 default:
1004 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1005 goto error;
1006 }
1007 default:
1008 break;
1009 }
1010
1011 if (!need_domain) {
1012 goto skip_domain;
1013 }
1014
1015 /*
1016 * Check domain type for specific "pre-action".
1017 */
1018 switch (cmd_ctx->lsm.domain.type) {
1019 case LTTNG_DOMAIN_KERNEL:
1020 if (!is_root) {
1021 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
1022 goto error;
1023 }
1024
1025 /* Kernel tracer check */
1026 if (!kernel_tracer_is_initialized()) {
1027 /* Basically, load kernel tracer modules */
1028 ret = init_kernel_tracer();
1029 if (ret != 0) {
1030 goto error;
1031 }
1032 }
1033
1034 /* Consumer is in an ERROR state. Report back to client */
1035 if (need_consumerd && uatomic_read(&kernel_consumerd_state) ==
1036 CONSUMER_ERROR) {
1037 ret = LTTNG_ERR_NO_KERNCONSUMERD;
1038 goto error;
1039 }
1040
1041 /* Need a session for kernel command */
1042 if (need_tracing_session) {
1043 if (cmd_ctx->session->kernel_session == NULL) {
1044 ret = create_kernel_session(cmd_ctx->session);
1045 if (ret != LTTNG_OK) {
1046 ret = LTTNG_ERR_KERN_SESS_FAIL;
1047 goto error;
1048 }
1049 }
1050
1051 /* Start the kernel consumer daemon */
1052 pthread_mutex_lock(&kconsumer_data.pid_mutex);
1053 if (kconsumer_data.pid == 0 &&
1054 cmd_ctx->lsm.cmd_type != LTTNG_REGISTER_CONSUMER) {
1055 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
1056 ret = start_consumerd(&kconsumer_data);
1057 if (ret < 0) {
1058 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
1059 goto error;
1060 }
1061 uatomic_set(&kernel_consumerd_state, CONSUMER_STARTED);
1062 } else {
1063 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
1064 }
1065
1066 /*
1067 * The consumer was just spawned so we need to add the socket to
1068 * the consumer output of the session if exist.
1069 */
1070 ret = consumer_create_socket(&kconsumer_data,
1071 cmd_ctx->session->kernel_session->consumer);
1072 if (ret < 0) {
1073 goto error;
1074 }
1075 }
1076
1077 break;
1078 case LTTNG_DOMAIN_JUL:
1079 case LTTNG_DOMAIN_LOG4J:
1080 case LTTNG_DOMAIN_PYTHON:
1081 case LTTNG_DOMAIN_UST:
1082 {
1083 if (!ust_app_supported()) {
1084 ret = LTTNG_ERR_NO_UST;
1085 goto error;
1086 }
1087
1088 /* Consumer is in an ERROR state. Report back to client */
1089 if (need_consumerd && uatomic_read(&ust_consumerd_state) ==
1090 CONSUMER_ERROR) {
1091 ret = LTTNG_ERR_NO_USTCONSUMERD;
1092 goto error;
1093 }
1094
1095 if (need_tracing_session) {
1096 /* Create UST session if none exist. */
1097 if (cmd_ctx->session->ust_session == NULL) {
1098 ret = create_ust_session(cmd_ctx->session,
1099 ALIGNED_CONST_PTR(cmd_ctx->lsm.domain));
1100 if (ret != LTTNG_OK) {
1101 goto error;
1102 }
1103 }
1104
1105 /* Start the UST consumer daemons */
1106 /* 64-bit */
1107 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
1108 if (config.consumerd64_bin_path.value &&
1109 ustconsumer64_data.pid == 0 &&
1110 cmd_ctx->lsm.cmd_type != LTTNG_REGISTER_CONSUMER) {
1111 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
1112 ret = start_consumerd(&ustconsumer64_data);
1113 if (ret < 0) {
1114 ret = LTTNG_ERR_UST_CONSUMER64_FAIL;
1115 uatomic_set(&ust_consumerd64_fd, -EINVAL);
1116 goto error;
1117 }
1118
1119 uatomic_set(&ust_consumerd64_fd, ustconsumer64_data.cmd_sock);
1120 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
1121 } else {
1122 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
1123 }
1124
1125 /*
1126 * Setup socket for consumer 64 bit. No need for atomic access
1127 * since it was set above and can ONLY be set in this thread.
1128 */
1129 ret = consumer_create_socket(&ustconsumer64_data,
1130 cmd_ctx->session->ust_session->consumer);
1131 if (ret < 0) {
1132 goto error;
1133 }
1134
1135 /* 32-bit */
1136 pthread_mutex_lock(&ustconsumer32_data.pid_mutex);
1137 if (config.consumerd32_bin_path.value &&
1138 ustconsumer32_data.pid == 0 &&
1139 cmd_ctx->lsm.cmd_type != LTTNG_REGISTER_CONSUMER) {
1140 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
1141 ret = start_consumerd(&ustconsumer32_data);
1142 if (ret < 0) {
1143 ret = LTTNG_ERR_UST_CONSUMER32_FAIL;
1144 uatomic_set(&ust_consumerd32_fd, -EINVAL);
1145 goto error;
1146 }
1147
1148 uatomic_set(&ust_consumerd32_fd, ustconsumer32_data.cmd_sock);
1149 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
1150 } else {
1151 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
1152 }
1153
1154 /*
1155 * Setup socket for consumer 32 bit. No need for atomic access
1156 * since it was set above and can ONLY be set in this thread.
1157 */
1158 ret = consumer_create_socket(&ustconsumer32_data,
1159 cmd_ctx->session->ust_session->consumer);
1160 if (ret < 0) {
1161 goto error;
1162 }
1163 }
1164 break;
1165 }
1166 default:
1167 break;
1168 }
1169 skip_domain:
1170
1171 /* Validate consumer daemon state when start/stop trace command */
1172 if (cmd_ctx->lsm.cmd_type == LTTNG_START_TRACE ||
1173 cmd_ctx->lsm.cmd_type == LTTNG_STOP_TRACE) {
1174 switch (cmd_ctx->lsm.domain.type) {
1175 case LTTNG_DOMAIN_NONE:
1176 break;
1177 case LTTNG_DOMAIN_JUL:
1178 case LTTNG_DOMAIN_LOG4J:
1179 case LTTNG_DOMAIN_PYTHON:
1180 case LTTNG_DOMAIN_UST:
1181 if (uatomic_read(&ust_consumerd_state) != CONSUMER_STARTED) {
1182 ret = LTTNG_ERR_NO_USTCONSUMERD;
1183 goto error;
1184 }
1185 break;
1186 case LTTNG_DOMAIN_KERNEL:
1187 if (uatomic_read(&kernel_consumerd_state) != CONSUMER_STARTED) {
1188 ret = LTTNG_ERR_NO_KERNCONSUMERD;
1189 goto error;
1190 }
1191 break;
1192 default:
1193 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1194 goto error;
1195 }
1196 }
1197
1198 /*
1199 * Check that the UID matches that of the tracing session.
1200 * The root user can interact with all sessions.
1201 */
1202 if (need_tracing_session) {
1203 if (!session_access_ok(cmd_ctx->session,
1204 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds)) ||
1205 cmd_ctx->session->destroyed) {
1206 ret = LTTNG_ERR_EPERM;
1207 goto error;
1208 }
1209 }
1210
1211 /*
1212 * Send relayd information to consumer as soon as we have a domain and a
1213 * session defined.
1214 */
1215 if (cmd_ctx->session && need_domain) {
1216 /*
1217 * Setup relayd if not done yet. If the relayd information was already
1218 * sent to the consumer, this call will gracefully return.
1219 */
1220 ret = cmd_setup_relayd(cmd_ctx->session);
1221 if (ret != LTTNG_OK) {
1222 goto error;
1223 }
1224 }
1225
1226 /* Process by command type */
1227 switch (cmd_ctx->lsm.cmd_type) {
1228 case LTTNG_ADD_CONTEXT:
1229 {
1230 /*
1231 * An LTTNG_ADD_CONTEXT command might have a supplementary
1232 * payload if the context being added is an application context.
1233 */
1234 if (cmd_ctx->lsm.u.context.ctx.ctx ==
1235 LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1236 char *provider_name = NULL, *context_name = NULL;
1237 size_t provider_name_len =
1238 cmd_ctx->lsm.u.context.provider_name_len;
1239 size_t context_name_len =
1240 cmd_ctx->lsm.u.context.context_name_len;
1241
1242 if (provider_name_len == 0 || context_name_len == 0) {
1243 /*
1244 * Application provider and context names MUST
1245 * be provided.
1246 */
1247 ret = -LTTNG_ERR_INVALID;
1248 goto error;
1249 }
1250
1251 provider_name = zmalloc(provider_name_len + 1);
1252 if (!provider_name) {
1253 ret = -LTTNG_ERR_NOMEM;
1254 goto error;
1255 }
1256 cmd_ctx->lsm.u.context.ctx.u.app_ctx.provider_name =
1257 provider_name;
1258
1259 context_name = zmalloc(context_name_len + 1);
1260 if (!context_name) {
1261 ret = -LTTNG_ERR_NOMEM;
1262 goto error_add_context;
1263 }
1264 cmd_ctx->lsm.u.context.ctx.u.app_ctx.ctx_name =
1265 context_name;
1266
1267 ret = lttcomm_recv_unix_sock(*sock, provider_name,
1268 provider_name_len);
1269 if (ret < 0) {
1270 goto error_add_context;
1271 }
1272
1273 ret = lttcomm_recv_unix_sock(*sock, context_name,
1274 context_name_len);
1275 if (ret < 0) {
1276 goto error_add_context;
1277 }
1278 }
1279
1280 /*
1281 * cmd_add_context assumes ownership of the provider and context
1282 * names.
1283 */
1284 ret = cmd_add_context(cmd_ctx->session,
1285 cmd_ctx->lsm.domain.type,
1286 cmd_ctx->lsm.u.context.channel_name,
1287 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.context.ctx),
1288 kernel_poll_pipe[1]);
1289
1290 cmd_ctx->lsm.u.context.ctx.u.app_ctx.provider_name = NULL;
1291 cmd_ctx->lsm.u.context.ctx.u.app_ctx.ctx_name = NULL;
1292 error_add_context:
1293 free(cmd_ctx->lsm.u.context.ctx.u.app_ctx.provider_name);
1294 free(cmd_ctx->lsm.u.context.ctx.u.app_ctx.ctx_name);
1295 if (ret < 0) {
1296 goto error;
1297 }
1298 break;
1299 }
1300 case LTTNG_DISABLE_CHANNEL:
1301 {
1302 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm.domain.type,
1303 cmd_ctx->lsm.u.disable.channel_name);
1304 break;
1305 }
1306 case LTTNG_DISABLE_EVENT:
1307 {
1308
1309 /*
1310 * FIXME: handle filter; for now we just receive the filter's
1311 * bytecode along with the filter expression which are sent by
1312 * liblttng-ctl and discard them.
1313 *
1314 * This fixes an issue where the client may block while sending
1315 * the filter payload and encounter an error because the session
1316 * daemon closes the socket without ever handling this data.
1317 */
1318 size_t count = cmd_ctx->lsm.u.disable.expression_len +
1319 cmd_ctx->lsm.u.disable.bytecode_len;
1320
1321 if (count) {
1322 char data[LTTNG_FILTER_MAX_LEN];
1323
1324 DBG("Discarding disable event command payload of size %zu", count);
1325 while (count) {
1326 ret = lttcomm_recv_unix_sock(*sock, data,
1327 count > sizeof(data) ? sizeof(data) : count);
1328 if (ret < 0) {
1329 goto error;
1330 }
1331
1332 count -= (size_t) ret;
1333 }
1334 }
1335 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm.domain.type,
1336 cmd_ctx->lsm.u.disable.channel_name,
1337 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.disable.event));
1338 break;
1339 }
1340 case LTTNG_ENABLE_CHANNEL:
1341 {
1342 cmd_ctx->lsm.u.channel.chan.attr.extended.ptr =
1343 (struct lttng_channel_extended *) &cmd_ctx->lsm.u.channel.extended;
1344 ret = cmd_enable_channel(cmd_ctx->session,
1345 ALIGNED_CONST_PTR(cmd_ctx->lsm.domain),
1346 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.channel.chan),
1347 kernel_poll_pipe[1]);
1348 break;
1349 }
1350 case LTTNG_PROCESS_ATTR_TRACKER_ADD_INCLUDE_VALUE:
1351 case LTTNG_PROCESS_ATTR_TRACKER_REMOVE_INCLUDE_VALUE:
1352 {
1353 struct lttng_dynamic_buffer payload;
1354 struct lttng_buffer_view payload_view;
1355 const bool add_value =
1356 cmd_ctx->lsm.cmd_type ==
1357 LTTNG_PROCESS_ATTR_TRACKER_ADD_INCLUDE_VALUE;
1358 const size_t name_len =
1359 cmd_ctx->lsm.u.process_attr_tracker_add_remove_include_value
1360 .name_len;
1361 const enum lttng_domain_type domain_type =
1362 (enum lttng_domain_type)
1363 cmd_ctx->lsm.domain.type;
1364 const enum lttng_process_attr process_attr =
1365 (enum lttng_process_attr) cmd_ctx->lsm.u
1366 .process_attr_tracker_add_remove_include_value
1367 .process_attr;
1368 const enum lttng_process_attr_value_type value_type =
1369 (enum lttng_process_attr_value_type) cmd_ctx
1370 ->lsm.u
1371 .process_attr_tracker_add_remove_include_value
1372 .value_type;
1373 struct process_attr_value *value;
1374 enum lttng_error_code ret_code;
1375 long login_name_max;
1376
1377 login_name_max = sysconf(_SC_LOGIN_NAME_MAX);
1378 if (login_name_max < 0) {
1379 PERROR("Failed to get _SC_LOGIN_NAME_MAX system configuration");
1380 ret = LTTNG_ERR_INVALID;
1381 goto error;
1382 }
1383
1384 /* Receive remaining variable length payload if applicable. */
1385 if (name_len > login_name_max) {
1386 /*
1387 * POSIX mandates user and group names that are at least
1388 * 8 characters long. Note that although shadow-utils
1389 * (useradd, groupaadd, etc.) use 32 chars as their
1390 * limit (from bits/utmp.h, UT_NAMESIZE),
1391 * LOGIN_NAME_MAX is defined to 256.
1392 */
1393 ERR("Rejecting process attribute tracker value %s as the provided exceeds the maximal allowed length: argument length = %zu, maximal length = %ld",
1394 add_value ? "addition" : "removal",
1395 name_len, login_name_max);
1396 ret = LTTNG_ERR_INVALID;
1397 goto error;
1398 }
1399
1400 lttng_dynamic_buffer_init(&payload);
1401 if (name_len != 0) {
1402 /*
1403 * Receive variable payload for user/group name
1404 * arguments.
1405 */
1406 ret = lttng_dynamic_buffer_set_size(&payload, name_len);
1407 if (ret) {
1408 ERR("Failed to allocate buffer to receive payload of %s process attribute tracker value argument",
1409 add_value ? "add" : "remove");
1410 ret = LTTNG_ERR_NOMEM;
1411 goto error_add_remove_tracker_value;
1412 }
1413
1414 ret = lttcomm_recv_unix_sock(
1415 *sock, payload.data, name_len);
1416 if (ret <= 0) {
1417 ERR("Failed to receive payload of %s process attribute tracker value argument",
1418 add_value ? "add" : "remove");
1419 *sock_error = 1;
1420 ret = LTTNG_ERR_INVALID_PROTOCOL;
1421 goto error_add_remove_tracker_value;
1422 }
1423 }
1424
1425 payload_view = lttng_buffer_view_from_dynamic_buffer(
1426 &payload, 0, name_len);
1427 if (name_len > 0 && !lttng_buffer_view_is_valid(&payload_view)) {
1428 ret = LTTNG_ERR_INVALID_PROTOCOL;
1429 goto error_add_remove_tracker_value;
1430 }
1431
1432 /*
1433 * Validate the value type and domains are legal for the process
1434 * attribute tracker that is specified and convert the value to
1435 * add/remove to the internal sessiond representation.
1436 */
1437 ret_code = process_attr_value_from_comm(domain_type,
1438 process_attr, value_type,
1439 &cmd_ctx->lsm.u.process_attr_tracker_add_remove_include_value
1440 .integral_value,
1441 &payload_view, &value);
1442 if (ret_code != LTTNG_OK) {
1443 ret = ret_code;
1444 goto error_add_remove_tracker_value;
1445 }
1446
1447 if (add_value) {
1448 ret = cmd_process_attr_tracker_inclusion_set_add_value(
1449 cmd_ctx->session, domain_type,
1450 process_attr, value);
1451 } else {
1452 ret = cmd_process_attr_tracker_inclusion_set_remove_value(
1453 cmd_ctx->session, domain_type,
1454 process_attr, value);
1455 }
1456 process_attr_value_destroy(value);
1457 error_add_remove_tracker_value:
1458 lttng_dynamic_buffer_reset(&payload);
1459 break;
1460 }
1461 case LTTNG_PROCESS_ATTR_TRACKER_GET_POLICY:
1462 {
1463 enum lttng_tracking_policy tracking_policy;
1464 const enum lttng_domain_type domain_type =
1465 (enum lttng_domain_type)
1466 cmd_ctx->lsm.domain.type;
1467 const enum lttng_process_attr process_attr =
1468 (enum lttng_process_attr) cmd_ctx->lsm.u
1469 .process_attr_tracker_get_tracking_policy
1470 .process_attr;
1471
1472 ret = cmd_process_attr_tracker_get_tracking_policy(
1473 cmd_ctx->session, domain_type, process_attr,
1474 &tracking_policy);
1475 if (ret != LTTNG_OK) {
1476 goto error;
1477 }
1478
1479 ret = setup_lttng_msg_no_cmd_header(cmd_ctx,
1480 &(uint32_t){tracking_policy}, sizeof(uint32_t));
1481 if (ret < 0) {
1482 ret = LTTNG_ERR_NOMEM;
1483 goto error;
1484 }
1485 ret = LTTNG_OK;
1486 break;
1487 }
1488 case LTTNG_PROCESS_ATTR_TRACKER_SET_POLICY:
1489 {
1490 const enum lttng_tracking_policy tracking_policy =
1491 (enum lttng_tracking_policy) cmd_ctx->lsm.u
1492 .process_attr_tracker_set_tracking_policy
1493 .tracking_policy;
1494 const enum lttng_domain_type domain_type =
1495 (enum lttng_domain_type)
1496 cmd_ctx->lsm.domain.type;
1497 const enum lttng_process_attr process_attr =
1498 (enum lttng_process_attr) cmd_ctx->lsm.u
1499 .process_attr_tracker_set_tracking_policy
1500 .process_attr;
1501
1502 ret = cmd_process_attr_tracker_set_tracking_policy(
1503 cmd_ctx->session, domain_type, process_attr,
1504 tracking_policy);
1505 if (ret != LTTNG_OK) {
1506 goto error;
1507 }
1508 break;
1509 }
1510 case LTTNG_PROCESS_ATTR_TRACKER_GET_INCLUSION_SET:
1511 {
1512 struct lttng_process_attr_values *values;
1513 struct lttng_dynamic_buffer reply;
1514 const enum lttng_domain_type domain_type =
1515 (enum lttng_domain_type)
1516 cmd_ctx->lsm.domain.type;
1517 const enum lttng_process_attr process_attr =
1518 (enum lttng_process_attr) cmd_ctx->lsm.u
1519 .process_attr_tracker_get_inclusion_set
1520 .process_attr;
1521
1522 ret = cmd_process_attr_tracker_get_inclusion_set(
1523 cmd_ctx->session, domain_type, process_attr,
1524 &values);
1525 if (ret != LTTNG_OK) {
1526 goto error;
1527 }
1528
1529 lttng_dynamic_buffer_init(&reply);
1530 ret = lttng_process_attr_values_serialize(values, &reply);
1531 if (ret < 0) {
1532 goto error_tracker_get_inclusion_set;
1533 }
1534
1535 ret = setup_lttng_msg_no_cmd_header(
1536 cmd_ctx, reply.data, reply.size);
1537 if (ret < 0) {
1538 ret = LTTNG_ERR_NOMEM;
1539 goto error_tracker_get_inclusion_set;
1540 }
1541 ret = LTTNG_OK;
1542
1543 error_tracker_get_inclusion_set:
1544 lttng_process_attr_values_destroy(values);
1545 lttng_dynamic_buffer_reset(&reply);
1546 break;
1547 }
1548 case LTTNG_ENABLE_EVENT:
1549 {
1550 struct lttng_event *ev = NULL;
1551 struct lttng_event_exclusion *exclusion = NULL;
1552 struct lttng_filter_bytecode *bytecode = NULL;
1553 char *filter_expression = NULL;
1554
1555 /* Handle exclusion events and receive it from the client. */
1556 if (cmd_ctx->lsm.u.enable.exclusion_count > 0) {
1557 size_t count = cmd_ctx->lsm.u.enable.exclusion_count;
1558
1559 exclusion = zmalloc(sizeof(struct lttng_event_exclusion) +
1560 (count * LTTNG_SYMBOL_NAME_LEN));
1561 if (!exclusion) {
1562 ret = LTTNG_ERR_EXCLUSION_NOMEM;
1563 goto error;
1564 }
1565
1566 DBG("Receiving var len exclusion event list from client ...");
1567 exclusion->count = count;
1568 ret = lttcomm_recv_unix_sock(*sock, exclusion->names,
1569 count * LTTNG_SYMBOL_NAME_LEN);
1570 if (ret <= 0) {
1571 DBG("Nothing recv() from client var len data... continuing");
1572 *sock_error = 1;
1573 free(exclusion);
1574 ret = LTTNG_ERR_EXCLUSION_INVAL;
1575 goto error;
1576 }
1577 }
1578
1579 /* Get filter expression from client. */
1580 if (cmd_ctx->lsm.u.enable.expression_len > 0) {
1581 size_t expression_len =
1582 cmd_ctx->lsm.u.enable.expression_len;
1583
1584 if (expression_len > LTTNG_FILTER_MAX_LEN) {
1585 ret = LTTNG_ERR_FILTER_INVAL;
1586 free(exclusion);
1587 goto error;
1588 }
1589
1590 filter_expression = zmalloc(expression_len);
1591 if (!filter_expression) {
1592 free(exclusion);
1593 ret = LTTNG_ERR_FILTER_NOMEM;
1594 goto error;
1595 }
1596
1597 /* Receive var. len. data */
1598 DBG("Receiving var len filter's expression from client ...");
1599 ret = lttcomm_recv_unix_sock(*sock, filter_expression,
1600 expression_len);
1601 if (ret <= 0) {
1602 DBG("Nothing recv() from client var len data... continuing");
1603 *sock_error = 1;
1604 free(filter_expression);
1605 free(exclusion);
1606 ret = LTTNG_ERR_FILTER_INVAL;
1607 goto error;
1608 }
1609 }
1610
1611 /* Handle filter and get bytecode from client. */
1612 if (cmd_ctx->lsm.u.enable.bytecode_len > 0) {
1613 size_t bytecode_len = cmd_ctx->lsm.u.enable.bytecode_len;
1614
1615 if (bytecode_len > LTTNG_FILTER_MAX_LEN) {
1616 ret = LTTNG_ERR_FILTER_INVAL;
1617 free(filter_expression);
1618 free(exclusion);
1619 goto error;
1620 }
1621
1622 bytecode = zmalloc(bytecode_len);
1623 if (!bytecode) {
1624 free(filter_expression);
1625 free(exclusion);
1626 ret = LTTNG_ERR_FILTER_NOMEM;
1627 goto error;
1628 }
1629
1630 /* Receive var. len. data */
1631 DBG("Receiving var len filter's bytecode from client ...");
1632 ret = lttcomm_recv_unix_sock(*sock, bytecode, bytecode_len);
1633 if (ret <= 0) {
1634 DBG("Nothing recv() from client var len data... continuing");
1635 *sock_error = 1;
1636 free(filter_expression);
1637 free(bytecode);
1638 free(exclusion);
1639 ret = LTTNG_ERR_FILTER_INVAL;
1640 goto error;
1641 }
1642
1643 if ((bytecode->len + sizeof(*bytecode)) != bytecode_len) {
1644 free(filter_expression);
1645 free(bytecode);
1646 free(exclusion);
1647 ret = LTTNG_ERR_FILTER_INVAL;
1648 goto error;
1649 }
1650 }
1651
1652 ev = lttng_event_copy(ALIGNED_CONST_PTR(cmd_ctx->lsm.u.enable.event));
1653 if (!ev) {
1654 DBG("Failed to copy event: %s",
1655 cmd_ctx->lsm.u.enable.event.name);
1656 free(filter_expression);
1657 free(bytecode);
1658 free(exclusion);
1659 ret = LTTNG_ERR_NOMEM;
1660 goto error;
1661 }
1662
1663
1664 if (cmd_ctx->lsm.u.enable.userspace_probe_location_len > 0) {
1665 /* Expect a userspace probe description. */
1666 ret = receive_userspace_probe(cmd_ctx, *sock, sock_error, ev);
1667 if (ret) {
1668 free(filter_expression);
1669 free(bytecode);
1670 free(exclusion);
1671 lttng_event_destroy(ev);
1672 goto error;
1673 }
1674 }
1675
1676 ret = cmd_enable_event(cmd_ctx->session,
1677 ALIGNED_CONST_PTR(cmd_ctx->lsm.domain),
1678 cmd_ctx->lsm.u.enable.channel_name,
1679 ev,
1680 filter_expression, bytecode, exclusion,
1681 kernel_poll_pipe[1]);
1682 lttng_event_destroy(ev);
1683 break;
1684 }
1685 case LTTNG_LIST_TRACEPOINTS:
1686 {
1687 struct lttng_event *events;
1688 ssize_t nb_events;
1689
1690 session_lock_list();
1691 nb_events = cmd_list_tracepoints(cmd_ctx->lsm.domain.type, &events);
1692 session_unlock_list();
1693 if (nb_events < 0) {
1694 /* Return value is a negative lttng_error_code. */
1695 ret = -nb_events;
1696 goto error;
1697 }
1698
1699 /*
1700 * Setup lttng message with payload size set to the event list size in
1701 * bytes and then copy list into the llm payload.
1702 */
1703 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, events,
1704 sizeof(struct lttng_event) * nb_events);
1705 free(events);
1706
1707 if (ret < 0) {
1708 goto setup_error;
1709 }
1710
1711 ret = LTTNG_OK;
1712 break;
1713 }
1714 case LTTNG_LIST_TRACEPOINT_FIELDS:
1715 {
1716 struct lttng_event_field *fields;
1717 ssize_t nb_fields;
1718
1719 session_lock_list();
1720 nb_fields = cmd_list_tracepoint_fields(cmd_ctx->lsm.domain.type,
1721 &fields);
1722 session_unlock_list();
1723 if (nb_fields < 0) {
1724 /* Return value is a negative lttng_error_code. */
1725 ret = -nb_fields;
1726 goto error;
1727 }
1728
1729 /*
1730 * Setup lttng message with payload size set to the event list size in
1731 * bytes and then copy list into the llm payload.
1732 */
1733 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, fields,
1734 sizeof(struct lttng_event_field) * nb_fields);
1735 free(fields);
1736
1737 if (ret < 0) {
1738 goto setup_error;
1739 }
1740
1741 ret = LTTNG_OK;
1742 break;
1743 }
1744 case LTTNG_LIST_SYSCALLS:
1745 {
1746 struct lttng_event *events;
1747 ssize_t nb_events;
1748
1749 nb_events = cmd_list_syscalls(&events);
1750 if (nb_events < 0) {
1751 /* Return value is a negative lttng_error_code. */
1752 ret = -nb_events;
1753 goto error;
1754 }
1755
1756 /*
1757 * Setup lttng message with payload size set to the event list size in
1758 * bytes and then copy list into the llm payload.
1759 */
1760 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, events,
1761 sizeof(struct lttng_event) * nb_events);
1762 free(events);
1763
1764 if (ret < 0) {
1765 goto setup_error;
1766 }
1767
1768 ret = LTTNG_OK;
1769 break;
1770 }
1771 case LTTNG_SET_CONSUMER_URI:
1772 {
1773 size_t nb_uri, len;
1774 struct lttng_uri *uris;
1775
1776 nb_uri = cmd_ctx->lsm.u.uri.size;
1777 len = nb_uri * sizeof(struct lttng_uri);
1778
1779 if (nb_uri == 0) {
1780 ret = LTTNG_ERR_INVALID;
1781 goto error;
1782 }
1783
1784 uris = zmalloc(len);
1785 if (uris == NULL) {
1786 ret = LTTNG_ERR_FATAL;
1787 goto error;
1788 }
1789
1790 /* Receive variable len data */
1791 DBG("Receiving %zu URI(s) from client ...", nb_uri);
1792 ret = lttcomm_recv_unix_sock(*sock, uris, len);
1793 if (ret <= 0) {
1794 DBG("No URIs received from client... continuing");
1795 *sock_error = 1;
1796 ret = LTTNG_ERR_SESSION_FAIL;
1797 free(uris);
1798 goto error;
1799 }
1800
1801 ret = cmd_set_consumer_uri(cmd_ctx->session, nb_uri, uris);
1802 free(uris);
1803 if (ret != LTTNG_OK) {
1804 goto error;
1805 }
1806
1807
1808 break;
1809 }
1810 case LTTNG_START_TRACE:
1811 {
1812 /*
1813 * On the first start, if we have a kernel session and we have
1814 * enabled time or size-based rotations, we have to make sure
1815 * the kernel tracer supports it.
1816 */
1817 if (!cmd_ctx->session->has_been_started && \
1818 cmd_ctx->session->kernel_session && \
1819 (cmd_ctx->session->rotate_timer_period || \
1820 cmd_ctx->session->rotate_size) && \
1821 !check_rotate_compatible()) {
1822 DBG("Kernel tracer version is not compatible with the rotation feature");
1823 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
1824 goto error;
1825 }
1826 ret = cmd_start_trace(cmd_ctx->session);
1827 break;
1828 }
1829 case LTTNG_STOP_TRACE:
1830 {
1831 ret = cmd_stop_trace(cmd_ctx->session);
1832 break;
1833 }
1834 case LTTNG_DESTROY_SESSION:
1835 {
1836 ret = cmd_destroy_session(cmd_ctx->session,
1837 notification_thread_handle,
1838 sock);
1839 break;
1840 }
1841 case LTTNG_LIST_DOMAINS:
1842 {
1843 ssize_t nb_dom;
1844 struct lttng_domain *domains = NULL;
1845
1846 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
1847 if (nb_dom < 0) {
1848 /* Return value is a negative lttng_error_code. */
1849 ret = -nb_dom;
1850 goto error;
1851 }
1852
1853 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, domains,
1854 nb_dom * sizeof(struct lttng_domain));
1855 free(domains);
1856
1857 if (ret < 0) {
1858 goto setup_error;
1859 }
1860
1861 ret = LTTNG_OK;
1862 break;
1863 }
1864 case LTTNG_LIST_CHANNELS:
1865 {
1866 ssize_t payload_size;
1867 struct lttng_channel *channels = NULL;
1868
1869 payload_size = cmd_list_channels(cmd_ctx->lsm.domain.type,
1870 cmd_ctx->session, &channels);
1871 if (payload_size < 0) {
1872 /* Return value is a negative lttng_error_code. */
1873 ret = -payload_size;
1874 goto error;
1875 }
1876
1877 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, channels,
1878 payload_size);
1879 free(channels);
1880
1881 if (ret < 0) {
1882 goto setup_error;
1883 }
1884
1885 ret = LTTNG_OK;
1886 break;
1887 }
1888 case LTTNG_LIST_EVENTS:
1889 {
1890 ssize_t list_ret;
1891 struct lttcomm_event_command_header cmd_header = {};
1892 size_t original_payload_size;
1893 size_t payload_size;
1894
1895 ret = setup_empty_lttng_msg(cmd_ctx);
1896 if (ret) {
1897 ret = LTTNG_ERR_NOMEM;
1898 goto setup_error;
1899 }
1900
1901 original_payload_size = cmd_ctx->reply_payload.buffer.size;
1902
1903 /* Extended infos are included at the end of the payload. */
1904 list_ret = cmd_list_events(cmd_ctx->lsm.domain.type,
1905 cmd_ctx->session,
1906 cmd_ctx->lsm.u.list.channel_name,
1907 &cmd_ctx->reply_payload);
1908 if (list_ret < 0) {
1909 /* Return value is a negative lttng_error_code. */
1910 ret = -list_ret;
1911 goto error;
1912 }
1913
1914 payload_size = cmd_ctx->reply_payload.buffer.size -
1915 sizeof(cmd_header) - original_payload_size;
1916 update_lttng_msg(cmd_ctx, sizeof(cmd_header), payload_size);
1917
1918 ret = LTTNG_OK;
1919 break;
1920 }
1921 case LTTNG_LIST_SESSIONS:
1922 {
1923 unsigned int nr_sessions;
1924 void *sessions_payload;
1925 size_t payload_len;
1926
1927 session_lock_list();
1928 nr_sessions = lttng_sessions_count(
1929 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1930 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
1931
1932 payload_len = (sizeof(struct lttng_session) * nr_sessions) +
1933 (sizeof(struct lttng_session_extended) * nr_sessions);
1934 sessions_payload = zmalloc(payload_len);
1935
1936 if (!sessions_payload) {
1937 session_unlock_list();
1938 ret = -ENOMEM;
1939 goto setup_error;
1940 }
1941
1942 cmd_list_lttng_sessions(sessions_payload, nr_sessions,
1943 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1944 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
1945 session_unlock_list();
1946
1947 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, sessions_payload,
1948 payload_len);
1949 free(sessions_payload);
1950
1951 if (ret < 0) {
1952 goto setup_error;
1953 }
1954
1955 ret = LTTNG_OK;
1956 break;
1957 }
1958 case LTTNG_REGISTER_CONSUMER:
1959 {
1960 struct consumer_data *cdata;
1961
1962 switch (cmd_ctx->lsm.domain.type) {
1963 case LTTNG_DOMAIN_KERNEL:
1964 cdata = &kconsumer_data;
1965 break;
1966 default:
1967 ret = LTTNG_ERR_UND;
1968 goto error;
1969 }
1970
1971 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm.domain.type,
1972 cmd_ctx->lsm.u.reg.path, cdata);
1973 break;
1974 }
1975 case LTTNG_DATA_PENDING:
1976 {
1977 int pending_ret;
1978 uint8_t pending_ret_byte;
1979
1980 pending_ret = cmd_data_pending(cmd_ctx->session);
1981
1982 /*
1983 * FIXME
1984 *
1985 * This function may returns 0 or 1 to indicate whether or not
1986 * there is data pending. In case of error, it should return an
1987 * LTTNG_ERR code. However, some code paths may still return
1988 * a nondescript error code, which we handle by returning an
1989 * "unknown" error.
1990 */
1991 if (pending_ret == 0 || pending_ret == 1) {
1992 /*
1993 * ret will be set to LTTNG_OK at the end of
1994 * this function.
1995 */
1996 } else if (pending_ret < 0) {
1997 ret = LTTNG_ERR_UNK;
1998 goto setup_error;
1999 } else {
2000 ret = pending_ret;
2001 goto setup_error;
2002 }
2003
2004 pending_ret_byte = (uint8_t) pending_ret;
2005
2006 /* 1 byte to return whether or not data is pending */
2007 ret = setup_lttng_msg_no_cmd_header(cmd_ctx,
2008 &pending_ret_byte, 1);
2009
2010 if (ret < 0) {
2011 goto setup_error;
2012 }
2013
2014 ret = LTTNG_OK;
2015 break;
2016 }
2017 case LTTNG_SNAPSHOT_ADD_OUTPUT:
2018 {
2019 uint32_t snapshot_id;
2020 struct lttcomm_lttng_output_id reply;
2021
2022 ret = cmd_snapshot_add_output(cmd_ctx->session,
2023 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.snapshot_output.output),
2024 &snapshot_id);
2025 if (ret != LTTNG_OK) {
2026 goto error;
2027 }
2028 reply.id = snapshot_id;
2029
2030 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &reply,
2031 sizeof(reply));
2032 if (ret < 0) {
2033 goto setup_error;
2034 }
2035
2036 /* Copy output list into message payload */
2037 ret = LTTNG_OK;
2038 break;
2039 }
2040 case LTTNG_SNAPSHOT_DEL_OUTPUT:
2041 {
2042 ret = cmd_snapshot_del_output(cmd_ctx->session,
2043 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.snapshot_output.output));
2044 break;
2045 }
2046 case LTTNG_SNAPSHOT_LIST_OUTPUT:
2047 {
2048 ssize_t nb_output;
2049 struct lttng_snapshot_output *outputs = NULL;
2050
2051 nb_output = cmd_snapshot_list_outputs(cmd_ctx->session, &outputs);
2052 if (nb_output < 0) {
2053 ret = -nb_output;
2054 goto error;
2055 }
2056
2057 assert((nb_output > 0 && outputs) || nb_output == 0);
2058 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, outputs,
2059 nb_output * sizeof(struct lttng_snapshot_output));
2060 free(outputs);
2061
2062 if (ret < 0) {
2063 goto setup_error;
2064 }
2065
2066 ret = LTTNG_OK;
2067 break;
2068 }
2069 case LTTNG_SNAPSHOT_RECORD:
2070 {
2071 ret = cmd_snapshot_record(cmd_ctx->session,
2072 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.snapshot_record.output),
2073 cmd_ctx->lsm.u.snapshot_record.wait);
2074 break;
2075 }
2076 case LTTNG_CREATE_SESSION_EXT:
2077 {
2078 struct lttng_dynamic_buffer payload;
2079 struct lttng_session_descriptor *return_descriptor = NULL;
2080
2081 lttng_dynamic_buffer_init(&payload);
2082 ret = cmd_create_session(cmd_ctx, *sock, &return_descriptor);
2083 if (ret != LTTNG_OK) {
2084 goto error;
2085 }
2086
2087 ret = lttng_session_descriptor_serialize(return_descriptor,
2088 &payload);
2089 if (ret) {
2090 ERR("Failed to serialize session descriptor in reply to \"create session\" command");
2091 lttng_session_descriptor_destroy(return_descriptor);
2092 ret = LTTNG_ERR_NOMEM;
2093 goto error;
2094 }
2095 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, payload.data,
2096 payload.size);
2097 if (ret) {
2098 lttng_session_descriptor_destroy(return_descriptor);
2099 ret = LTTNG_ERR_NOMEM;
2100 goto error;
2101 }
2102 lttng_dynamic_buffer_reset(&payload);
2103 lttng_session_descriptor_destroy(return_descriptor);
2104 ret = LTTNG_OK;
2105 break;
2106 }
2107 case LTTNG_SAVE_SESSION:
2108 {
2109 ret = cmd_save_sessions(&cmd_ctx->lsm.u.save_session.attr,
2110 &cmd_ctx->creds);
2111 break;
2112 }
2113 case LTTNG_SET_SESSION_SHM_PATH:
2114 {
2115 ret = cmd_set_session_shm_path(cmd_ctx->session,
2116 cmd_ctx->lsm.u.set_shm_path.shm_path);
2117 break;
2118 }
2119 case LTTNG_REGENERATE_METADATA:
2120 {
2121 ret = cmd_regenerate_metadata(cmd_ctx->session);
2122 break;
2123 }
2124 case LTTNG_REGENERATE_STATEDUMP:
2125 {
2126 ret = cmd_regenerate_statedump(cmd_ctx->session);
2127 break;
2128 }
2129 case LTTNG_REGISTER_TRIGGER:
2130 {
2131 struct lttng_trigger *payload_trigger;
2132 struct lttng_trigger *return_trigger;
2133 size_t original_reply_payload_size;
2134 size_t reply_payload_size;
2135 const struct lttng_credentials cmd_creds = {
2136 .uid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.uid),
2137 .gid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.gid),
2138 };
2139
2140 ret = setup_empty_lttng_msg(cmd_ctx);
2141 if (ret) {
2142 ret = LTTNG_ERR_NOMEM;
2143 goto setup_error;
2144 }
2145
2146 ret = receive_lttng_trigger(
2147 cmd_ctx, *sock, sock_error, &payload_trigger);
2148 if (ret != LTTNG_OK) {
2149 goto error;
2150 }
2151
2152 original_reply_payload_size = cmd_ctx->reply_payload.buffer.size;
2153
2154 ret = cmd_register_trigger(&cmd_creds, payload_trigger,
2155 notification_thread_handle, &return_trigger);
2156 if (ret != LTTNG_OK) {
2157 lttng_trigger_put(payload_trigger);
2158 goto error;
2159 }
2160
2161 ret = lttng_trigger_serialize(return_trigger, &cmd_ctx->reply_payload);
2162 lttng_trigger_put(payload_trigger);
2163 lttng_trigger_put(return_trigger);
2164 if (ret) {
2165 ERR("Failed to serialize trigger in reply to \"register trigger\" command");
2166 ret = LTTNG_ERR_NOMEM;
2167 goto error;
2168 }
2169
2170 reply_payload_size = cmd_ctx->reply_payload.buffer.size -
2171 original_reply_payload_size;
2172
2173 update_lttng_msg(cmd_ctx, 0, reply_payload_size);
2174
2175 ret = LTTNG_OK;
2176 break;
2177 }
2178 case LTTNG_UNREGISTER_TRIGGER:
2179 {
2180 struct lttng_trigger *payload_trigger;
2181 const struct lttng_credentials cmd_creds = {
2182 .uid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.uid),
2183 .gid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.gid),
2184 };
2185
2186 ret = receive_lttng_trigger(
2187 cmd_ctx, *sock, sock_error, &payload_trigger);
2188 if (ret != LTTNG_OK) {
2189 goto error;
2190 }
2191
2192 ret = cmd_unregister_trigger(&cmd_creds, payload_trigger,
2193 notification_thread_handle);
2194 lttng_trigger_put(payload_trigger);
2195 break;
2196 }
2197 case LTTNG_ROTATE_SESSION:
2198 {
2199 struct lttng_rotate_session_return rotate_return;
2200
2201 DBG("Client rotate session \"%s\"", cmd_ctx->session->name);
2202
2203 memset(&rotate_return, 0, sizeof(rotate_return));
2204 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
2205 DBG("Kernel tracer version is not compatible with the rotation feature");
2206 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
2207 goto error;
2208 }
2209
2210 ret = cmd_rotate_session(cmd_ctx->session, &rotate_return,
2211 false,
2212 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
2213 if (ret < 0) {
2214 ret = -ret;
2215 goto error;
2216 }
2217
2218 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &rotate_return,
2219 sizeof(rotate_return));
2220 if (ret < 0) {
2221 ret = -ret;
2222 goto error;
2223 }
2224
2225 ret = LTTNG_OK;
2226 break;
2227 }
2228 case LTTNG_ROTATION_GET_INFO:
2229 {
2230 struct lttng_rotation_get_info_return get_info_return;
2231
2232 memset(&get_info_return, 0, sizeof(get_info_return));
2233 ret = cmd_rotate_get_info(cmd_ctx->session, &get_info_return,
2234 cmd_ctx->lsm.u.get_rotation_info.rotation_id);
2235 if (ret < 0) {
2236 ret = -ret;
2237 goto error;
2238 }
2239
2240 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &get_info_return,
2241 sizeof(get_info_return));
2242 if (ret < 0) {
2243 ret = -ret;
2244 goto error;
2245 }
2246
2247 ret = LTTNG_OK;
2248 break;
2249 }
2250 case LTTNG_ROTATION_SET_SCHEDULE:
2251 {
2252 bool set_schedule;
2253 enum lttng_rotation_schedule_type schedule_type;
2254 uint64_t value;
2255
2256 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
2257 DBG("Kernel tracer version does not support session rotations");
2258 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
2259 goto error;
2260 }
2261
2262 set_schedule = cmd_ctx->lsm.u.rotation_set_schedule.set == 1;
2263 schedule_type = (enum lttng_rotation_schedule_type) cmd_ctx->lsm.u.rotation_set_schedule.type;
2264 value = cmd_ctx->lsm.u.rotation_set_schedule.value;
2265
2266 ret = cmd_rotation_set_schedule(cmd_ctx->session,
2267 set_schedule,
2268 schedule_type,
2269 value,
2270 notification_thread_handle);
2271 if (ret != LTTNG_OK) {
2272 goto error;
2273 }
2274
2275 break;
2276 }
2277 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
2278 {
2279 struct lttng_session_list_schedules_return schedules = {
2280 .periodic.set = !!cmd_ctx->session->rotate_timer_period,
2281 .periodic.value = cmd_ctx->session->rotate_timer_period,
2282 .size.set = !!cmd_ctx->session->rotate_size,
2283 .size.value = cmd_ctx->session->rotate_size,
2284 };
2285
2286 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &schedules,
2287 sizeof(schedules));
2288 if (ret < 0) {
2289 ret = -ret;
2290 goto error;
2291 }
2292
2293 ret = LTTNG_OK;
2294 break;
2295 }
2296 case LTTNG_CLEAR_SESSION:
2297 {
2298 ret = cmd_clear_session(cmd_ctx->session, sock);
2299 break;
2300 }
2301 case LTTNG_LIST_TRIGGERS:
2302 {
2303 struct lttng_triggers *return_triggers = NULL;
2304 size_t original_payload_size;
2305 size_t payload_size;
2306
2307 ret = setup_empty_lttng_msg(cmd_ctx);
2308 if (ret) {
2309 ret = LTTNG_ERR_NOMEM;
2310 goto setup_error;
2311 }
2312
2313 original_payload_size = cmd_ctx->reply_payload.buffer.size;
2314
2315 ret = cmd_list_triggers(cmd_ctx,
2316 notification_thread_handle, &return_triggers);
2317 if (ret != LTTNG_OK) {
2318 goto error;
2319 }
2320
2321 assert(return_triggers);
2322 ret = lttng_triggers_serialize(
2323 return_triggers, &cmd_ctx->reply_payload);
2324 lttng_triggers_destroy(return_triggers);
2325 if (ret) {
2326 ERR("Failed to serialize triggers in reply to `list triggers` command");
2327 ret = LTTNG_ERR_NOMEM;
2328 goto error;
2329 }
2330
2331 payload_size = cmd_ctx->reply_payload.buffer.size -
2332 original_payload_size;
2333
2334 update_lttng_msg(cmd_ctx, 0, payload_size);
2335
2336 ret = LTTNG_OK;
2337 break;
2338 }
2339 default:
2340 ret = LTTNG_ERR_UND;
2341 break;
2342 }
2343
2344 error:
2345 if (cmd_ctx->reply_payload.buffer.size == 0) {
2346 DBG("Missing llm header, creating one.");
2347 if (setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0) < 0) {
2348 goto setup_error;
2349 }
2350 }
2351 /* Set return code */
2352 ((struct lttcomm_lttng_msg *) (cmd_ctx->reply_payload.buffer.data))->ret_code = ret;
2353 setup_error:
2354 if (cmd_ctx->session) {
2355 session_unlock(cmd_ctx->session);
2356 session_put(cmd_ctx->session);
2357 cmd_ctx->session = NULL;
2358 }
2359 if (need_tracing_session) {
2360 session_unlock_list();
2361 }
2362 init_setup_error:
2363 assert(!rcu_read_ongoing());
2364 return ret;
2365 }
2366
2367 static int create_client_sock(void)
2368 {
2369 int ret, client_sock;
2370 const mode_t old_umask = umask(0);
2371
2372 /* Create client tool unix socket */
2373 client_sock = lttcomm_create_unix_sock(config.client_unix_sock_path.value);
2374 if (client_sock < 0) {
2375 ERR("Create unix sock failed: %s", config.client_unix_sock_path.value);
2376 ret = -1;
2377 goto end;
2378 }
2379
2380 /* Set the cloexec flag */
2381 ret = utils_set_fd_cloexec(client_sock);
2382 if (ret < 0) {
2383 ERR("Unable to set CLOEXEC flag to the client Unix socket (fd: %d). "
2384 "Continuing but note that the consumer daemon will have a "
2385 "reference to this socket on exec()", client_sock);
2386 }
2387
2388 /* File permission MUST be 660 */
2389 ret = chmod(config.client_unix_sock_path.value, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
2390 if (ret < 0) {
2391 ERR("Set file permissions failed: %s",
2392 config.client_unix_sock_path.value);
2393 PERROR("chmod");
2394 (void) lttcomm_close_unix_sock(client_sock);
2395 ret = -1;
2396 goto end;
2397 }
2398 DBG("Created client socket (fd = %i)", client_sock);
2399 ret = client_sock;
2400 end:
2401 umask(old_umask);
2402 return ret;
2403 }
2404
2405 static void cleanup_client_thread(void *data)
2406 {
2407 struct lttng_pipe *quit_pipe = data;
2408
2409 lttng_pipe_destroy(quit_pipe);
2410 }
2411
2412 static void thread_init_cleanup(void *data)
2413 {
2414 set_thread_status(false);
2415 }
2416
2417 /*
2418 * This thread manage all clients request using the unix client socket for
2419 * communication.
2420 */
2421 static void *thread_manage_clients(void *data)
2422 {
2423 int sock = -1, ret, i, pollfd, err = -1;
2424 int sock_error;
2425 uint32_t revents, nb_fd;
2426 struct lttng_poll_event events;
2427 const int client_sock = thread_state.client_sock;
2428 struct lttng_pipe *quit_pipe = data;
2429 const int thread_quit_pipe_fd = lttng_pipe_get_readfd(quit_pipe);
2430 struct command_ctx cmd_ctx = {};
2431
2432 DBG("[thread] Manage client started");
2433
2434 lttng_payload_init(&cmd_ctx.reply_payload);
2435
2436 is_root = (getuid() == 0);
2437
2438 pthread_cleanup_push(thread_init_cleanup, NULL);
2439
2440 rcu_register_thread();
2441
2442 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_CMD);
2443
2444 health_code_update();
2445
2446 ret = lttcomm_listen_unix_sock(client_sock);
2447 if (ret < 0) {
2448 goto error_listen;
2449 }
2450
2451 /*
2452 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2453 * more will be added to this poll set.
2454 */
2455 ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
2456 if (ret < 0) {
2457 goto error_create_poll;
2458 }
2459
2460 /* Add the application registration socket */
2461 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
2462 if (ret < 0) {
2463 goto error;
2464 }
2465
2466 /* Add thread quit pipe */
2467 ret = lttng_poll_add(&events, thread_quit_pipe_fd, LPOLLIN | LPOLLERR);
2468 if (ret < 0) {
2469 goto error;
2470 }
2471
2472 /* Set state as running. */
2473 set_thread_status(true);
2474 pthread_cleanup_pop(0);
2475
2476 /* This testpoint is after we signal readiness to the parent. */
2477 if (testpoint(sessiond_thread_manage_clients)) {
2478 goto error;
2479 }
2480
2481 if (testpoint(sessiond_thread_manage_clients_before_loop)) {
2482 goto error;
2483 }
2484
2485 health_code_update();
2486
2487 while (1) {
2488 const struct cmd_completion_handler *cmd_completion_handler;
2489
2490 cmd_ctx.creds = (lttng_sock_cred) {
2491 .uid = UINT32_MAX,
2492 .gid = UINT32_MAX,
2493 };
2494 cmd_ctx.session = NULL;
2495 lttng_payload_clear(&cmd_ctx.reply_payload);
2496 cmd_ctx.lttng_msg_size = 0;
2497
2498 DBG("Accepting client command ...");
2499
2500 /* Inifinite blocking call, waiting for transmission */
2501 restart:
2502 health_poll_entry();
2503 ret = lttng_poll_wait(&events, -1);
2504 health_poll_exit();
2505 if (ret < 0) {
2506 /*
2507 * Restart interrupted system call.
2508 */
2509 if (errno == EINTR) {
2510 goto restart;
2511 }
2512 goto error;
2513 }
2514
2515 nb_fd = ret;
2516
2517 for (i = 0; i < nb_fd; i++) {
2518 revents = LTTNG_POLL_GETEV(&events, i);
2519 pollfd = LTTNG_POLL_GETFD(&events, i);
2520
2521 health_code_update();
2522
2523 if (pollfd == thread_quit_pipe_fd) {
2524 err = 0;
2525 goto exit;
2526 } else {
2527 /* Event on the registration socket */
2528 if (revents & LPOLLIN) {
2529 continue;
2530 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2531 ERR("Client socket poll error");
2532 goto error;
2533 } else {
2534 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
2535 goto error;
2536 }
2537 }
2538 }
2539
2540 DBG("Wait for client response");
2541
2542 health_code_update();
2543
2544 sock = lttcomm_accept_unix_sock(client_sock);
2545 if (sock < 0) {
2546 goto error;
2547 }
2548
2549 /*
2550 * Set the CLOEXEC flag. Return code is useless because either way, the
2551 * show must go on.
2552 */
2553 (void) utils_set_fd_cloexec(sock);
2554
2555 /* Set socket option for credentials retrieval */
2556 ret = lttcomm_setsockopt_creds_unix_sock(sock);
2557 if (ret < 0) {
2558 goto error;
2559 }
2560
2561 health_code_update();
2562
2563 /*
2564 * Data is received from the lttng client. The struct
2565 * lttcomm_session_msg (lsm) contains the command and data request of
2566 * the client.
2567 */
2568 DBG("Receiving data from client ...");
2569 ret = lttcomm_recv_creds_unix_sock(sock, &cmd_ctx.lsm,
2570 sizeof(struct lttcomm_session_msg), &cmd_ctx.creds);
2571 if (ret != sizeof(struct lttcomm_session_msg)) {
2572 DBG("Incomplete recv() from client... continuing");
2573 ret = close(sock);
2574 if (ret) {
2575 PERROR("close");
2576 }
2577 sock = -1;
2578 continue;
2579 }
2580
2581 health_code_update();
2582
2583 // TODO: Validate cmd_ctx including sanity check for
2584 // security purpose.
2585
2586 rcu_thread_online();
2587 /*
2588 * This function dispatch the work to the kernel or userspace tracer
2589 * libs and fill the lttcomm_lttng_msg data structure of all the needed
2590 * informations for the client. The command context struct contains
2591 * everything this function may needs.
2592 */
2593 ret = process_client_msg(&cmd_ctx, &sock, &sock_error);
2594 rcu_thread_offline();
2595 if (ret < 0) {
2596 if (sock >= 0) {
2597 ret = close(sock);
2598 if (ret) {
2599 PERROR("close");
2600 }
2601 }
2602 sock = -1;
2603 /*
2604 * TODO: Inform client somehow of the fatal error. At
2605 * this point, ret < 0 means that a zmalloc failed
2606 * (ENOMEM). Error detected but still accept
2607 * command, unless a socket error has been
2608 * detected.
2609 */
2610 continue;
2611 }
2612
2613 cmd_completion_handler = cmd_pop_completion_handler();
2614 if (cmd_completion_handler) {
2615 enum lttng_error_code completion_code;
2616
2617 completion_code = cmd_completion_handler->run(
2618 cmd_completion_handler->data);
2619 if (completion_code != LTTNG_OK) {
2620 continue;
2621 }
2622 }
2623
2624 health_code_update();
2625
2626 if (sock >= 0) {
2627 struct lttng_payload_view view =
2628 lttng_payload_view_from_payload(
2629 &cmd_ctx.reply_payload,
2630 0, -1);
2631 struct lttcomm_lttng_msg *llm = (typeof(
2632 llm)) cmd_ctx.reply_payload.buffer.data;
2633
2634 assert(cmd_ctx.reply_payload.buffer.size >= sizeof(*llm));
2635 assert(cmd_ctx.lttng_msg_size == cmd_ctx.reply_payload.buffer.size);
2636
2637 llm->fd_count = lttng_payload_view_get_fd_handle_count(&view);
2638
2639 DBG("Sending response (size: %d, retcode: %s (%d))",
2640 cmd_ctx.lttng_msg_size,
2641 lttng_strerror(-llm->ret_code),
2642 llm->ret_code);
2643 ret = send_unix_sock(sock, &view);
2644 if (ret < 0) {
2645 ERR("Failed to send data back to client");
2646 }
2647
2648 /* End of transmission */
2649 ret = close(sock);
2650 if (ret) {
2651 PERROR("close");
2652 }
2653 }
2654 sock = -1;
2655
2656 health_code_update();
2657 }
2658
2659 exit:
2660 error:
2661 if (sock >= 0) {
2662 ret = close(sock);
2663 if (ret) {
2664 PERROR("close");
2665 }
2666 }
2667
2668 lttng_poll_clean(&events);
2669
2670 error_listen:
2671 error_create_poll:
2672 unlink(config.client_unix_sock_path.value);
2673 ret = close(client_sock);
2674 if (ret) {
2675 PERROR("close");
2676 }
2677
2678 if (err) {
2679 health_error();
2680 ERR("Health error occurred in %s", __func__);
2681 }
2682
2683 health_unregister(health_sessiond);
2684
2685 DBG("Client thread dying");
2686 lttng_payload_reset(&cmd_ctx.reply_payload);
2687 rcu_unregister_thread();
2688 return NULL;
2689 }
2690
2691 static
2692 bool shutdown_client_thread(void *thread_data)
2693 {
2694 struct lttng_pipe *client_quit_pipe = thread_data;
2695 const int write_fd = lttng_pipe_get_writefd(client_quit_pipe);
2696
2697 return notify_thread_pipe(write_fd) == 1;
2698 }
2699
2700 struct lttng_thread *launch_client_thread(void)
2701 {
2702 bool thread_running;
2703 struct lttng_pipe *client_quit_pipe;
2704 struct lttng_thread *thread = NULL;
2705 int client_sock_fd = -1;
2706
2707 sem_init(&thread_state.ready, 0, 0);
2708 client_quit_pipe = lttng_pipe_open(FD_CLOEXEC);
2709 if (!client_quit_pipe) {
2710 goto error;
2711 }
2712
2713 client_sock_fd = create_client_sock();
2714 if (client_sock_fd < 0) {
2715 goto error;
2716 }
2717
2718 thread_state.client_sock = client_sock_fd;
2719 thread = lttng_thread_create("Client management",
2720 thread_manage_clients,
2721 shutdown_client_thread,
2722 cleanup_client_thread,
2723 client_quit_pipe);
2724 if (!thread) {
2725 goto error;
2726 }
2727 /* The client thread now owns the client sock fd and the quit pipe. */
2728 client_sock_fd = -1;
2729 client_quit_pipe = NULL;
2730
2731 /*
2732 * This thread is part of the threads that need to be fully
2733 * initialized before the session daemon is marked as "ready".
2734 */
2735 thread_running = wait_thread_status();
2736 if (!thread_running) {
2737 goto error;
2738 }
2739 return thread;
2740 error:
2741 if (client_sock_fd >= 0) {
2742 if (close(client_sock_fd)) {
2743 PERROR("Failed to close client socket");
2744 }
2745 }
2746 lttng_thread_put(thread);
2747 cleanup_client_thread(client_quit_pipe);
2748 return NULL;
2749 }
LTTng 2.0 tools and control repository
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