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Standardize quit pipes behavior
[lttng-tools.git] / src / bin / lttng-sessiond / client.cpp
1 /*
2 * Copyright (C) 2011 EfficiOS Inc.
3 * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 * Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com>
5 *
6 * SPDX-License-Identifier: GPL-2.0-only
7 *
8 */
9
10 #include "common/buffer-view.hpp"
11 #include "common/compat/socket.hpp"
12 #include "common/dynamic-array.hpp"
13 #include "common/dynamic-buffer.hpp"
14 #include "common/fd-handle.hpp"
15 #include "common/payload-view.hpp"
16 #include "common/payload.hpp"
17 #include "common/sessiond-comm/sessiond-comm.hpp"
18 #include "lttng/lttng-error.h"
19 #include "lttng/tracker.h"
20 #include <common/compat/getenv.hpp>
21 #include <common/tracker.hpp>
22 #include <common/unix.hpp>
23 #include <common/utils.hpp>
24 #include <lttng/error-query-internal.hpp>
25 #include <lttng/event-internal.hpp>
26 #include <lttng/session-descriptor-internal.hpp>
27 #include <lttng/session-internal.hpp>
28 #include <lttng/userspace-probe-internal.hpp>
29 #include <pthread.h>
30 #include <signal.h>
31 #include <stddef.h>
32 #include <stdint.h>
33 #include <sys/stat.h>
34 #include <unistd.h>
35
36 #include "agent-thread.hpp"
37 #include "clear.hpp"
38 #include "client.hpp"
39 #include "cmd.hpp"
40 #include "health-sessiond.hpp"
41 #include "kernel.hpp"
42 #include "lttng-sessiond.hpp"
43 #include "manage-consumer.hpp"
44 #include "save.hpp"
45 #include "testpoint.hpp"
46 #include "utils.hpp"
47
48 namespace {
49 bool is_root;
50
51 struct thread_state {
52 sem_t ready;
53 bool running;
54 int client_sock;
55 } thread_state;
56 } /* namespace */
57
58 static void set_thread_status(bool running)
59 {
60 DBG("Marking client thread's state as %s", running ? "running" : "error");
61 thread_state.running = running;
62 sem_post(&thread_state.ready);
63 }
64
65 static bool wait_thread_status(void)
66 {
67 DBG("Waiting for client thread to be ready");
68 sem_wait(&thread_state.ready);
69 if (thread_state.running) {
70 DBG("Client thread is ready");
71 } else {
72 ERR("Initialization of client thread failed");
73 }
74
75 return thread_state.running;
76 }
77
78 /*
79 * Setup the outgoing data buffer for the response (llm) by allocating the
80 * right amount of memory and copying the original information from the lsm
81 * structure.
82 *
83 * Return 0 on success, negative value on error.
84 */
85 static int setup_lttng_msg(struct command_ctx *cmd_ctx,
86 const void *payload_buf, size_t payload_len,
87 const void *cmd_header_buf, size_t cmd_header_len)
88 {
89 int ret = 0;
90 const size_t header_len = sizeof(struct lttcomm_lttng_msg);
91 const size_t total_msg_size = header_len + cmd_header_len + payload_len;
92 lttcomm_lttng_msg llm {};
93
94 llm.cmd_type = cmd_ctx->lsm.cmd_type;
95 llm.pid = (uint32_t) cmd_ctx->lsm.domain.attr.pid;
96 llm.cmd_header_size = (uint32_t) cmd_header_len;
97 llm.data_size = (uint32_t) payload_len;
98
99 ret = lttng_dynamic_buffer_set_size(&cmd_ctx->reply_payload.buffer, 0);
100 if (ret) {
101 goto end;
102 }
103
104 lttng_dynamic_pointer_array_clear(&cmd_ctx->reply_payload._fd_handles);
105
106 cmd_ctx->lttng_msg_size = total_msg_size;
107
108 /* Append reply header. */
109 ret = lttng_dynamic_buffer_append(
110 &cmd_ctx->reply_payload.buffer, &llm, sizeof(llm));
111 if (ret) {
112 goto end;
113 }
114
115 /* Append command header. */
116 if (cmd_header_len) {
117 ret = lttng_dynamic_buffer_append(
118 &cmd_ctx->reply_payload.buffer, cmd_header_buf,
119 cmd_header_len);
120 if (ret) {
121 goto end;
122 }
123 }
124
125 /* Append payload. */
126 if (payload_len) {
127 ret = lttng_dynamic_buffer_append(
128 &cmd_ctx->reply_payload.buffer, payload_buf,
129 payload_len);
130 if (ret) {
131 goto end;
132 }
133 }
134
135 end:
136 return ret;
137 }
138
139 static int setup_empty_lttng_msg(struct command_ctx *cmd_ctx)
140 {
141 int ret;
142 const struct lttcomm_lttng_msg llm = {};
143
144 ret = lttng_dynamic_buffer_set_size(&cmd_ctx->reply_payload.buffer, 0);
145 if (ret) {
146 goto end;
147 }
148
149 /* Append place-holder reply header. */
150 ret = lttng_dynamic_buffer_append(
151 &cmd_ctx->reply_payload.buffer, &llm, sizeof(llm));
152 if (ret) {
153 goto end;
154 }
155
156 cmd_ctx->lttng_msg_size = sizeof(llm);
157 end:
158 return ret;
159 }
160
161 static void update_lttng_msg(struct command_ctx *cmd_ctx, size_t cmd_header_len,
162 size_t payload_len)
163 {
164 const size_t header_len = sizeof(struct lttcomm_lttng_msg);
165 const size_t total_msg_size = header_len + cmd_header_len + payload_len;
166 struct lttcomm_lttng_msg *p_llm;
167 lttcomm_lttng_msg llm {};
168
169 llm.cmd_type = cmd_ctx->lsm.cmd_type;
170 llm.pid = (uint32_t) cmd_ctx->lsm.domain.attr.pid;
171 llm.cmd_header_size = (uint32_t) cmd_header_len;
172 llm.data_size = (uint32_t) payload_len;
173
174 LTTNG_ASSERT(cmd_ctx->reply_payload.buffer.size >= sizeof(llm));
175
176 p_llm = (typeof(p_llm)) cmd_ctx->reply_payload.buffer.data;
177
178 /* Update existing header. */
179 memcpy(p_llm, &llm, sizeof(llm));
180
181 cmd_ctx->lttng_msg_size = total_msg_size;
182 }
183
184 /*
185 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
186 * exec or it will fail.
187 */
188 static int spawn_consumer_thread(struct consumer_data *consumer_data)
189 {
190 return launch_consumer_management_thread(consumer_data) ? 0 : -1;
191 }
192
193 /*
194 * Fork and exec a consumer daemon (consumerd).
195 *
196 * Return pid if successful else -1.
197 */
198 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
199 {
200 int ret;
201 pid_t pid;
202 const char *consumer_to_use;
203 const char *verbosity;
204 struct stat st;
205
206 DBG("Spawning consumerd");
207
208 pid = fork();
209 if (pid == 0) {
210 /*
211 * Exec consumerd.
212 */
213 if (the_config.verbose_consumer) {
214 verbosity = "--verbose";
215 } else if (lttng_opt_quiet) {
216 verbosity = "--quiet";
217 } else {
218 verbosity = "";
219 }
220
221 switch (consumer_data->type) {
222 case LTTNG_CONSUMER_KERNEL:
223 /*
224 * Find out which consumerd to execute. We will first try the
225 * 64-bit path, then the sessiond's installation directory, and
226 * fallback on the 32-bit one,
227 */
228 DBG3("Looking for a kernel consumer at these locations:");
229 DBG3(" 1) %s", the_config.consumerd64_bin_path.value ? : "NULL");
230 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, DEFAULT_CONSUMERD_FILE);
231 DBG3(" 3) %s", the_config.consumerd32_bin_path.value ? : "NULL");
232 if (stat(the_config.consumerd64_bin_path.value, &st) == 0) {
233 DBG3("Found location #1");
234 consumer_to_use = the_config.consumerd64_bin_path.value;
235 } else if (stat(INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE, &st) == 0) {
236 DBG3("Found location #2");
237 consumer_to_use = INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE;
238 } else if (the_config.consumerd32_bin_path.value &&
239 stat(the_config.consumerd32_bin_path.value, &st) == 0) {
240 DBG3("Found location #3");
241 consumer_to_use = the_config.consumerd32_bin_path.value;
242 } else {
243 DBG("Could not find any valid consumerd executable");
244 ret = -EINVAL;
245 goto error;
246 }
247 DBG("Using kernel consumer at: %s", consumer_to_use);
248 (void) execl(consumer_to_use, "lttng-consumerd",
249 verbosity, "-k", "--consumerd-cmd-sock",
250 consumer_data->cmd_unix_sock_path,
251 "--consumerd-err-sock",
252 consumer_data->err_unix_sock_path,
253 "--group",
254 the_config.tracing_group_name.value,
255 NULL);
256 break;
257 case LTTNG_CONSUMER64_UST:
258 {
259 if (the_config.consumerd64_lib_dir.value) {
260 const char *tmp;
261 size_t tmplen;
262 char *tmpnew;
263
264 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
265 if (!tmp) {
266 tmp = "";
267 }
268 tmplen = strlen(the_config.consumerd64_lib_dir.value) + 1 /* : */ + strlen(tmp);
269 tmpnew = zmalloc<char>(tmplen + 1 /* \0 */);
270 if (!tmpnew) {
271 ret = -ENOMEM;
272 goto error;
273 }
274 strcat(tmpnew, the_config.consumerd64_lib_dir.value);
275 if (tmp[0] != '\0') {
276 strcat(tmpnew, ":");
277 strcat(tmpnew, tmp);
278 }
279 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
280 free(tmpnew);
281 if (ret) {
282 ret = -errno;
283 goto error;
284 }
285 }
286 DBG("Using 64-bit UST consumer at: %s",
287 the_config.consumerd64_bin_path.value);
288 (void) execl(the_config.consumerd64_bin_path.value,
289 "lttng-consumerd", verbosity, "-u",
290 "--consumerd-cmd-sock",
291 consumer_data->cmd_unix_sock_path,
292 "--consumerd-err-sock",
293 consumer_data->err_unix_sock_path,
294 "--group",
295 the_config.tracing_group_name.value,
296 NULL);
297 break;
298 }
299 case LTTNG_CONSUMER32_UST:
300 {
301 if (the_config.consumerd32_lib_dir.value) {
302 const char *tmp;
303 size_t tmplen;
304 char *tmpnew;
305
306 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
307 if (!tmp) {
308 tmp = "";
309 }
310 tmplen = strlen(the_config.consumerd32_lib_dir.value) + 1 /* : */ + strlen(tmp);
311 tmpnew = zmalloc<char>(tmplen + 1 /* \0 */);
312 if (!tmpnew) {
313 ret = -ENOMEM;
314 goto error;
315 }
316 strcat(tmpnew, the_config.consumerd32_lib_dir.value);
317 if (tmp[0] != '\0') {
318 strcat(tmpnew, ":");
319 strcat(tmpnew, tmp);
320 }
321 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
322 free(tmpnew);
323 if (ret) {
324 ret = -errno;
325 goto error;
326 }
327 }
328 DBG("Using 32-bit UST consumer at: %s",
329 the_config.consumerd32_bin_path.value);
330 (void) execl(the_config.consumerd32_bin_path.value,
331 "lttng-consumerd", verbosity, "-u",
332 "--consumerd-cmd-sock",
333 consumer_data->cmd_unix_sock_path,
334 "--consumerd-err-sock",
335 consumer_data->err_unix_sock_path,
336 "--group",
337 the_config.tracing_group_name.value,
338 NULL);
339 break;
340 }
341 default:
342 ERR("unknown consumer type");
343 errno = 0;
344 }
345 if (errno != 0) {
346 PERROR("Consumer execl()");
347 }
348 /* Reaching this point, we got a failure on our execl(). */
349 exit(EXIT_FAILURE);
350 } else if (pid > 0) {
351 ret = pid;
352 } else {
353 PERROR("start consumer fork");
354 ret = -errno;
355 }
356 error:
357 return ret;
358 }
359
360 /*
361 * Spawn the consumerd daemon and session daemon thread.
362 */
363 static int start_consumerd(struct consumer_data *consumer_data)
364 {
365 int ret;
366
367 /*
368 * Set the listen() state on the socket since there is a possible race
369 * between the exec() of the consumer daemon and this call if place in the
370 * consumer thread. See bug #366 for more details.
371 */
372 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
373 if (ret < 0) {
374 goto error;
375 }
376
377 pthread_mutex_lock(&consumer_data->pid_mutex);
378 if (consumer_data->pid != 0) {
379 pthread_mutex_unlock(&consumer_data->pid_mutex);
380 goto end;
381 }
382
383 ret = spawn_consumerd(consumer_data);
384 if (ret < 0) {
385 ERR("Spawning consumerd failed");
386 pthread_mutex_unlock(&consumer_data->pid_mutex);
387 goto error;
388 }
389
390 /* Setting up the consumer_data pid */
391 consumer_data->pid = ret;
392 DBG2("Consumer pid %d", consumer_data->pid);
393 pthread_mutex_unlock(&consumer_data->pid_mutex);
394
395 DBG2("Spawning consumer control thread");
396 ret = spawn_consumer_thread(consumer_data);
397 if (ret < 0) {
398 ERR("Fatal error spawning consumer control thread");
399 goto error;
400 }
401
402 end:
403 return 0;
404
405 error:
406 /* Cleanup already created sockets on error. */
407 if (consumer_data->err_sock >= 0) {
408 int err;
409
410 err = close(consumer_data->err_sock);
411 if (err < 0) {
412 PERROR("close consumer data error socket");
413 }
414 }
415 return ret;
416 }
417
418 /*
419 * Copy consumer output from the tracing session to the domain session. The
420 * function also applies the right modification on a per domain basis for the
421 * trace files destination directory.
422 */
423 static int copy_session_consumer(int domain, struct ltt_session *session)
424 {
425 int ret;
426 const char *dir_name;
427 struct consumer_output *consumer;
428
429 LTTNG_ASSERT(session);
430 LTTNG_ASSERT(session->consumer);
431
432 switch (domain) {
433 case LTTNG_DOMAIN_KERNEL:
434 DBG3("Copying tracing session consumer output in kernel session");
435 /*
436 * XXX: We should audit the session creation and what this function
437 * does "extra" in order to avoid a destroy since this function is used
438 * in the domain session creation (kernel and ust) only. Same for UST
439 * domain.
440 */
441 if (session->kernel_session->consumer) {
442 consumer_output_put(session->kernel_session->consumer);
443 }
444 session->kernel_session->consumer =
445 consumer_copy_output(session->consumer);
446 /* Ease our life a bit for the next part */
447 consumer = session->kernel_session->consumer;
448 dir_name = DEFAULT_KERNEL_TRACE_DIR;
449 break;
450 case LTTNG_DOMAIN_JUL:
451 case LTTNG_DOMAIN_LOG4J:
452 case LTTNG_DOMAIN_PYTHON:
453 case LTTNG_DOMAIN_UST:
454 DBG3("Copying tracing session consumer output in UST session");
455 if (session->ust_session->consumer) {
456 consumer_output_put(session->ust_session->consumer);
457 }
458 session->ust_session->consumer =
459 consumer_copy_output(session->consumer);
460 /* Ease our life a bit for the next part */
461 consumer = session->ust_session->consumer;
462 dir_name = DEFAULT_UST_TRACE_DIR;
463 break;
464 default:
465 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
466 goto error;
467 }
468
469 /* Append correct directory to subdir */
470 ret = lttng_strncpy(consumer->domain_subdir, dir_name,
471 sizeof(consumer->domain_subdir));
472 if (ret) {
473 ret = LTTNG_ERR_UNK;
474 goto error;
475 }
476 DBG3("Copy session consumer subdir %s", consumer->domain_subdir);
477 ret = LTTNG_OK;
478
479 error:
480 return ret;
481 }
482
483 /*
484 * Create an UST session and add it to the session ust list.
485 */
486 static int create_ust_session(struct ltt_session *session,
487 const struct lttng_domain *domain)
488 {
489 int ret;
490 struct ltt_ust_session *lus = NULL;
491
492 LTTNG_ASSERT(session);
493 LTTNG_ASSERT(domain);
494 LTTNG_ASSERT(session->consumer);
495
496 switch (domain->type) {
497 case LTTNG_DOMAIN_JUL:
498 case LTTNG_DOMAIN_LOG4J:
499 case LTTNG_DOMAIN_PYTHON:
500 case LTTNG_DOMAIN_UST:
501 break;
502 default:
503 ERR("Unknown UST domain on create session %d", domain->type);
504 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
505 goto error;
506 }
507
508 DBG("Creating UST session");
509
510 lus = trace_ust_create_session(session->id);
511 if (lus == NULL) {
512 ret = LTTNG_ERR_UST_SESS_FAIL;
513 goto error;
514 }
515
516 lus->uid = session->uid;
517 lus->gid = session->gid;
518 lus->output_traces = session->output_traces;
519 lus->snapshot_mode = session->snapshot_mode;
520 lus->live_timer_interval = session->live_timer;
521 session->ust_session = lus;
522 if (session->shm_path[0]) {
523 strncpy(lus->root_shm_path, session->shm_path,
524 sizeof(lus->root_shm_path));
525 lus->root_shm_path[sizeof(lus->root_shm_path) - 1] = '\0';
526 strncpy(lus->shm_path, session->shm_path,
527 sizeof(lus->shm_path));
528 lus->shm_path[sizeof(lus->shm_path) - 1] = '\0';
529 strncat(lus->shm_path, "/ust",
530 sizeof(lus->shm_path) - strlen(lus->shm_path) - 1);
531 }
532 /* Copy session output to the newly created UST session */
533 ret = copy_session_consumer(domain->type, session);
534 if (ret != LTTNG_OK) {
535 goto error;
536 }
537
538 return LTTNG_OK;
539
540 error:
541 free(lus);
542 session->ust_session = NULL;
543 return ret;
544 }
545
546 /*
547 * Create a kernel tracer session then create the default channel.
548 */
549 static int create_kernel_session(struct ltt_session *session)
550 {
551 int ret;
552
553 DBG("Creating kernel session");
554
555 ret = kernel_create_session(session);
556 if (ret < 0) {
557 ret = LTTNG_ERR_KERN_SESS_FAIL;
558 goto error_create;
559 }
560
561 /* Code flow safety */
562 LTTNG_ASSERT(session->kernel_session);
563
564 /* Copy session output to the newly created Kernel session */
565 ret = copy_session_consumer(LTTNG_DOMAIN_KERNEL, session);
566 if (ret != LTTNG_OK) {
567 goto error;
568 }
569
570 session->kernel_session->uid = session->uid;
571 session->kernel_session->gid = session->gid;
572 session->kernel_session->output_traces = session->output_traces;
573 session->kernel_session->snapshot_mode = session->snapshot_mode;
574 session->kernel_session->is_live_session = session->live_timer != 0;
575
576 return LTTNG_OK;
577
578 error:
579 trace_kernel_destroy_session(session->kernel_session);
580 session->kernel_session = NULL;
581 error_create:
582 return ret;
583 }
584
585 /*
586 * Count number of session permitted by uid/gid.
587 */
588 static unsigned int lttng_sessions_count(uid_t uid,
589 gid_t gid __attribute__((unused)))
590 {
591 unsigned int i = 0;
592 struct ltt_session *session;
593 const struct ltt_session_list *session_list = session_get_list();
594
595 DBG("Counting number of available session for UID %d", uid);
596 cds_list_for_each_entry(session, &session_list->head, list) {
597 if (!session_get(session)) {
598 continue;
599 }
600 session_lock(session);
601 /* Only count the sessions the user can control. */
602 if (session_access_ok(session, uid) &&
603 !session->destroyed) {
604 i++;
605 }
606 session_unlock(session);
607 session_put(session);
608 }
609 return i;
610 }
611
612 static enum lttng_error_code receive_lttng_trigger(struct command_ctx *cmd_ctx,
613 int sock,
614 int *sock_error,
615 struct lttng_trigger **_trigger)
616 {
617 int ret;
618 size_t trigger_len;
619 ssize_t sock_recv_len;
620 enum lttng_error_code ret_code;
621 struct lttng_payload trigger_payload;
622 struct lttng_trigger *trigger = NULL;
623
624 lttng_payload_init(&trigger_payload);
625 trigger_len = (size_t) cmd_ctx->lsm.u.trigger.length;
626 ret = lttng_dynamic_buffer_set_size(
627 &trigger_payload.buffer, trigger_len);
628 if (ret) {
629 ret_code = LTTNG_ERR_NOMEM;
630 goto end;
631 }
632
633 sock_recv_len = lttcomm_recv_unix_sock(
634 sock, trigger_payload.buffer.data, trigger_len);
635 if (sock_recv_len < 0 || sock_recv_len != trigger_len) {
636 ERR("Failed to receive trigger in command payload");
637 *sock_error = 1;
638 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
639 goto end;
640 }
641
642 /* Receive fds, if any. */
643 if (cmd_ctx->lsm.fd_count > 0) {
644 sock_recv_len = lttcomm_recv_payload_fds_unix_sock(
645 sock, cmd_ctx->lsm.fd_count, &trigger_payload);
646 if (sock_recv_len > 0 &&
647 sock_recv_len != cmd_ctx->lsm.fd_count * sizeof(int)) {
648 ERR("Failed to receive all file descriptors for trigger in command payload: expected fd count = %u, ret = %d",
649 cmd_ctx->lsm.fd_count, (int) ret);
650 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
651 *sock_error = 1;
652 goto end;
653 } else if (sock_recv_len <= 0) {
654 ERR("Failed to receive file descriptors for trigger in command payload: expected fd count = %u, ret = %d",
655 cmd_ctx->lsm.fd_count, (int) ret);
656 ret_code = LTTNG_ERR_FATAL;
657 *sock_error = 1;
658 goto end;
659 }
660 }
661
662 /* Deserialize trigger. */
663 {
664 struct lttng_payload_view view =
665 lttng_payload_view_from_payload(
666 &trigger_payload, 0, -1);
667
668 if (lttng_trigger_create_from_payload(&view, &trigger) !=
669 trigger_len) {
670 ERR("Invalid trigger received as part of command payload");
671 ret_code = LTTNG_ERR_INVALID_TRIGGER;
672 lttng_trigger_put(trigger);
673 goto end;
674 }
675 }
676
677 *_trigger = trigger;
678 ret_code = LTTNG_OK;
679
680 end:
681 lttng_payload_reset(&trigger_payload);
682 return ret_code;
683 }
684
685 static enum lttng_error_code receive_lttng_error_query(struct command_ctx *cmd_ctx,
686 int sock,
687 int *sock_error,
688 struct lttng_error_query **_query)
689 {
690 int ret;
691 size_t query_len;
692 ssize_t sock_recv_len;
693 enum lttng_error_code ret_code;
694 struct lttng_payload query_payload;
695 struct lttng_error_query *query = NULL;
696
697 lttng_payload_init(&query_payload);
698 query_len = (size_t) cmd_ctx->lsm.u.error_query.length;
699 ret = lttng_dynamic_buffer_set_size(&query_payload.buffer, query_len);
700 if (ret) {
701 ret_code = LTTNG_ERR_NOMEM;
702 goto end;
703 }
704
705 sock_recv_len = lttcomm_recv_unix_sock(
706 sock, query_payload.buffer.data, query_len);
707 if (sock_recv_len < 0 || sock_recv_len != query_len) {
708 ERR("Failed to receive error query in command payload");
709 *sock_error = 1;
710 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
711 goto end;
712 }
713
714 /* Receive fds, if any. */
715 if (cmd_ctx->lsm.fd_count > 0) {
716 sock_recv_len = lttcomm_recv_payload_fds_unix_sock(
717 sock, cmd_ctx->lsm.fd_count, &query_payload);
718 if (sock_recv_len > 0 &&
719 sock_recv_len != cmd_ctx->lsm.fd_count * sizeof(int)) {
720 ERR("Failed to receive all file descriptors for error query in command payload: expected fd count = %u, ret = %d",
721 cmd_ctx->lsm.fd_count, (int) ret);
722 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
723 *sock_error = 1;
724 goto end;
725 } else if (sock_recv_len <= 0) {
726 ERR("Failed to receive file descriptors for error query in command payload: expected fd count = %u, ret = %d",
727 cmd_ctx->lsm.fd_count, (int) ret);
728 ret_code = LTTNG_ERR_FATAL;
729 *sock_error = 1;
730 goto end;
731 }
732 }
733
734 /* Deserialize error query. */
735 {
736 struct lttng_payload_view view =
737 lttng_payload_view_from_payload(
738 &query_payload, 0, -1);
739
740 if (lttng_error_query_create_from_payload(&view, &query) !=
741 query_len) {
742 ERR("Invalid error query received as part of command payload");
743 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
744 goto end;
745 }
746 }
747
748 *_query = query;
749 ret_code = LTTNG_OK;
750
751 end:
752 lttng_payload_reset(&query_payload);
753 return ret_code;
754 }
755
756 static enum lttng_error_code receive_lttng_event(struct command_ctx *cmd_ctx,
757 int sock,
758 int *sock_error,
759 struct lttng_event **out_event,
760 char **out_filter_expression,
761 struct lttng_bytecode **out_bytecode,
762 struct lttng_event_exclusion **out_exclusion)
763 {
764 int ret;
765 size_t event_len;
766 ssize_t sock_recv_len;
767 enum lttng_error_code ret_code;
768 struct lttng_payload event_payload;
769 struct lttng_event *local_event = NULL;
770 char *local_filter_expression = NULL;
771 struct lttng_bytecode *local_bytecode = NULL;
772 struct lttng_event_exclusion *local_exclusion = NULL;
773
774 lttng_payload_init(&event_payload);
775 if (cmd_ctx->lsm.cmd_type == LTTCOMM_SESSIOND_COMMAND_ENABLE_EVENT) {
776 event_len = (size_t) cmd_ctx->lsm.u.enable.length;
777 } else if (cmd_ctx->lsm.cmd_type == LTTCOMM_SESSIOND_COMMAND_DISABLE_EVENT) {
778 event_len = (size_t) cmd_ctx->lsm.u.disable.length;
779 } else {
780 abort();
781 }
782
783 ret = lttng_dynamic_buffer_set_size(&event_payload.buffer, event_len);
784 if (ret) {
785 ret_code = LTTNG_ERR_NOMEM;
786 goto end;
787 }
788
789 sock_recv_len = lttcomm_recv_unix_sock(
790 sock, event_payload.buffer.data, event_len);
791 if (sock_recv_len < 0 || sock_recv_len != event_len) {
792 ERR("Failed to receive event in command payload");
793 *sock_error = 1;
794 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
795 goto end;
796 }
797
798 /* Receive fds, if any. */
799 if (cmd_ctx->lsm.fd_count > 0) {
800 sock_recv_len = lttcomm_recv_payload_fds_unix_sock(
801 sock, cmd_ctx->lsm.fd_count, &event_payload);
802 if (sock_recv_len > 0 &&
803 sock_recv_len != cmd_ctx->lsm.fd_count * sizeof(int)) {
804 ERR("Failed to receive all file descriptors for event in command payload: expected fd count = %u, ret = %d",
805 cmd_ctx->lsm.fd_count, (int) ret);
806 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
807 *sock_error = 1;
808 goto end;
809 } else if (sock_recv_len <= 0) {
810 ERR("Failed to receive file descriptors for event in command payload: expected fd count = %u, ret = %d",
811 cmd_ctx->lsm.fd_count, (int) ret);
812 ret_code = LTTNG_ERR_FATAL;
813 *sock_error = 1;
814 goto end;
815 }
816 }
817
818 /* Deserialize event. */
819 {
820 ssize_t len;
821 struct lttng_payload_view event_view =
822 lttng_payload_view_from_payload(
823 &event_payload, 0, -1);
824
825 len = lttng_event_create_from_payload(&event_view, &local_event,
826 &local_exclusion, &local_filter_expression,
827 &local_bytecode);
828
829 if (len < 0) {
830 ERR("Failed to create an event from the received buffer");
831 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
832 goto end;
833 }
834
835 if (len != event_len) {
836 ERR("Userspace probe location from the received buffer is not the advertised length: header length = %zu" PRIu32 ", payload length = %zd", event_len, len);
837 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
838 goto end;
839 }
840 }
841
842 *out_event = local_event;
843 *out_exclusion = local_exclusion;
844 *out_filter_expression = local_filter_expression;
845 *out_bytecode = local_bytecode;
846 local_event = NULL;
847 local_exclusion = NULL;
848 local_filter_expression = NULL;
849 local_bytecode = NULL;
850
851 ret_code = LTTNG_OK;
852
853 end:
854 lttng_payload_reset(&event_payload);
855 lttng_event_destroy(local_event);
856 free(local_filter_expression);
857 free(local_bytecode);
858 free(local_exclusion);
859 return ret_code;
860 }
861
862 static enum lttng_error_code receive_lttng_event_context(
863 const struct command_ctx *cmd_ctx,
864 int sock,
865 int *sock_error,
866 struct lttng_event_context **out_event_context)
867 {
868 int ret;
869 const size_t event_context_len =
870 (size_t) cmd_ctx->lsm.u.context.length;
871 ssize_t sock_recv_len;
872 enum lttng_error_code ret_code;
873 struct lttng_payload event_context_payload;
874 struct lttng_event_context *context = NULL;
875
876 lttng_payload_init(&event_context_payload);
877
878 ret = lttng_dynamic_buffer_set_size(&event_context_payload.buffer,
879 event_context_len);
880 if (ret) {
881 ret_code = LTTNG_ERR_NOMEM;
882 goto end;
883 }
884
885 sock_recv_len = lttcomm_recv_unix_sock(
886 sock, event_context_payload.buffer.data,
887 event_context_len);
888 if (sock_recv_len < 0 || sock_recv_len != event_context_len) {
889 ERR("Failed to receive event context in command payload");
890 *sock_error = 1;
891 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
892 goto end;
893 }
894
895 /* Deserialize event. */
896 {
897 ssize_t len;
898 struct lttng_payload_view event_context_view =
899 lttng_payload_view_from_payload(
900 &event_context_payload, 0, -1);
901
902 len = lttng_event_context_create_from_payload(
903 &event_context_view, &context);
904
905 if (len < 0) {
906 ERR("Failed to create a event context from the received buffer");
907 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
908 goto end;
909 }
910
911 if (len != event_context_len) {
912 ERR("Event context from the received buffer is not the advertised length: expected length = %zu, payload length = %zd", event_context_len, len);
913 ret_code = LTTNG_ERR_INVALID_PROTOCOL;
914 goto end;
915 }
916 }
917
918 *out_event_context = context;
919 context = NULL;
920 ret_code = LTTNG_OK;
921
922 end:
923 lttng_event_context_destroy(context);
924 lttng_payload_reset(&event_context_payload);
925 return ret_code;
926 }
927
928 /*
929 * Version of setup_lttng_msg() without command header.
930 */
931 static int setup_lttng_msg_no_cmd_header(struct command_ctx *cmd_ctx,
932 void *payload_buf, size_t payload_len)
933 {
934 return setup_lttng_msg(cmd_ctx, payload_buf, payload_len, NULL, 0);
935 }
936
937 /*
938 * Check if the current kernel tracer supports the session rotation feature.
939 * Return 1 if it does, 0 otherwise.
940 */
941 static int check_rotate_compatible(void)
942 {
943 int ret = 1;
944
945 if (the_kernel_tracer_version.major != 2 ||
946 the_kernel_tracer_version.minor < 11) {
947 DBG("Kernel tracer version is not compatible with the rotation feature");
948 ret = 0;
949 }
950
951 return ret;
952 }
953
954 /*
955 * Send data on a unix socket using the liblttsessiondcomm API.
956 *
957 * Return lttcomm error code.
958 */
959 static int send_unix_sock(int sock, struct lttng_payload_view *view)
960 {
961 int ret;
962 const int fd_count = lttng_payload_view_get_fd_handle_count(view);
963
964 /* Check valid length */
965 if (view->buffer.size == 0) {
966 ret = -1;
967 goto end;
968 }
969
970 ret = lttcomm_send_unix_sock(
971 sock, view->buffer.data, view->buffer.size);
972 if (ret < 0) {
973 goto end;
974 }
975
976 if (fd_count > 0) {
977 ret = lttcomm_send_payload_view_fds_unix_sock(sock, view);
978 if (ret < 0) {
979 goto end;
980 }
981 }
982
983 end:
984 return ret;
985 }
986
987 /*
988 * Process the command requested by the lttng client within the command
989 * context structure. This function make sure that the return structure (llm)
990 * is set and ready for transmission before returning.
991 *
992 * Return any error encountered or 0 for success.
993 *
994 * "sock" is only used for special-case var. len data.
995 * A command may assume the ownership of the socket, in which case its value
996 * should be set to -1.
997 */
998 static int process_client_msg(struct command_ctx *cmd_ctx, int *sock,
999 int *sock_error)
1000 {
1001 int ret = LTTNG_OK;
1002 bool need_tracing_session = true;
1003 bool need_domain;
1004 bool need_consumerd;
1005
1006 if (!lttcomm_sessiond_command_is_valid((lttcomm_sessiond_command) cmd_ctx->lsm.cmd_type)) {
1007 ERR("Unknown client command received: command id = %" PRIu32,
1008 cmd_ctx->lsm.cmd_type);
1009 ret = LTTNG_ERR_UND;
1010 goto error;
1011 }
1012
1013 DBG("Processing client command '%s\' (%d)",
1014 lttcomm_sessiond_command_str((lttcomm_sessiond_command) cmd_ctx->lsm.cmd_type),
1015 cmd_ctx->lsm.cmd_type);
1016
1017 *sock_error = 0;
1018
1019 switch (cmd_ctx->lsm.cmd_type) {
1020 case LTTCOMM_SESSIOND_COMMAND_CREATE_SESSION_EXT:
1021 case LTTCOMM_SESSIOND_COMMAND_DESTROY_SESSION:
1022 case LTTCOMM_SESSIOND_COMMAND_LIST_SESSIONS:
1023 case LTTCOMM_SESSIOND_COMMAND_LIST_DOMAINS:
1024 case LTTCOMM_SESSIOND_COMMAND_START_TRACE:
1025 case LTTCOMM_SESSIOND_COMMAND_STOP_TRACE:
1026 case LTTCOMM_SESSIOND_COMMAND_DATA_PENDING:
1027 case LTTCOMM_SESSIOND_COMMAND_SNAPSHOT_ADD_OUTPUT:
1028 case LTTCOMM_SESSIOND_COMMAND_SNAPSHOT_DEL_OUTPUT:
1029 case LTTCOMM_SESSIOND_COMMAND_SNAPSHOT_LIST_OUTPUT:
1030 case LTTCOMM_SESSIOND_COMMAND_SNAPSHOT_RECORD:
1031 case LTTCOMM_SESSIOND_COMMAND_SAVE_SESSION:
1032 case LTTCOMM_SESSIOND_COMMAND_SET_SESSION_SHM_PATH:
1033 case LTTCOMM_SESSIOND_COMMAND_REGENERATE_METADATA:
1034 case LTTCOMM_SESSIOND_COMMAND_REGENERATE_STATEDUMP:
1035 case LTTCOMM_SESSIOND_COMMAND_ROTATE_SESSION:
1036 case LTTCOMM_SESSIOND_COMMAND_ROTATION_GET_INFO:
1037 case LTTCOMM_SESSIOND_COMMAND_ROTATION_SET_SCHEDULE:
1038 case LTTCOMM_SESSIOND_COMMAND_SESSION_LIST_ROTATION_SCHEDULES:
1039 case LTTCOMM_SESSIOND_COMMAND_CLEAR_SESSION:
1040 case LTTCOMM_SESSIOND_COMMAND_LIST_TRIGGERS:
1041 case LTTCOMM_SESSIOND_COMMAND_EXECUTE_ERROR_QUERY:
1042 need_domain = false;
1043 break;
1044 default:
1045 need_domain = true;
1046 }
1047
1048 /* Needs a functioning consumerd? */
1049 switch (cmd_ctx->lsm.cmd_type) {
1050 case LTTCOMM_SESSIOND_COMMAND_REGISTER_TRIGGER:
1051 case LTTCOMM_SESSIOND_COMMAND_UNREGISTER_TRIGGER:
1052 case LTTCOMM_SESSIOND_COMMAND_EXECUTE_ERROR_QUERY:
1053 need_consumerd = false;
1054 break;
1055 default:
1056 need_consumerd = true;
1057 break;
1058 }
1059
1060 if (the_config.no_kernel && need_domain &&
1061 cmd_ctx->lsm.domain.type == LTTNG_DOMAIN_KERNEL) {
1062 if (!is_root) {
1063 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
1064 } else {
1065 ret = LTTNG_ERR_KERN_NA;
1066 }
1067 goto error;
1068 }
1069
1070 /* Deny register consumer if we already have a spawned consumer. */
1071 if (cmd_ctx->lsm.cmd_type == LTTCOMM_SESSIOND_COMMAND_REGISTER_CONSUMER) {
1072 pthread_mutex_lock(&the_kconsumer_data.pid_mutex);
1073 if (the_kconsumer_data.pid > 0) {
1074 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
1075 pthread_mutex_unlock(&the_kconsumer_data.pid_mutex);
1076 goto error;
1077 }
1078 pthread_mutex_unlock(&the_kconsumer_data.pid_mutex);
1079 }
1080
1081 /*
1082 * Check for command that don't needs to allocate a returned payload. We do
1083 * this here so we don't have to make the call for no payload at each
1084 * command.
1085 */
1086 switch(cmd_ctx->lsm.cmd_type) {
1087 case LTTCOMM_SESSIOND_COMMAND_LIST_SESSIONS:
1088 case LTTCOMM_SESSIOND_COMMAND_LIST_TRACEPOINTS:
1089 case LTTCOMM_SESSIOND_COMMAND_LIST_TRACEPOINT_FIELDS:
1090 case LTTCOMM_SESSIOND_COMMAND_LIST_DOMAINS:
1091 case LTTCOMM_SESSIOND_COMMAND_LIST_CHANNELS:
1092 case LTTCOMM_SESSIOND_COMMAND_LIST_EVENTS:
1093 case LTTCOMM_SESSIOND_COMMAND_LIST_SYSCALLS:
1094 case LTTCOMM_SESSIOND_COMMAND_SESSION_LIST_ROTATION_SCHEDULES:
1095 case LTTCOMM_SESSIOND_COMMAND_PROCESS_ATTR_TRACKER_GET_POLICY:
1096 case LTTCOMM_SESSIOND_COMMAND_PROCESS_ATTR_TRACKER_GET_INCLUSION_SET:
1097 case LTTCOMM_SESSIOND_COMMAND_DATA_PENDING:
1098 case LTTCOMM_SESSIOND_COMMAND_ROTATE_SESSION:
1099 case LTTCOMM_SESSIOND_COMMAND_ROTATION_GET_INFO:
1100 case LTTCOMM_SESSIOND_COMMAND_REGISTER_TRIGGER:
1101 case LTTCOMM_SESSIOND_COMMAND_LIST_TRIGGERS:
1102 case LTTCOMM_SESSIOND_COMMAND_EXECUTE_ERROR_QUERY:
1103 break;
1104 default:
1105 /* Setup lttng message with no payload */
1106 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0);
1107 if (ret < 0) {
1108 /* This label does not try to unlock the session */
1109 goto init_setup_error;
1110 }
1111 }
1112
1113 /* Commands that DO NOT need a session. */
1114 switch (cmd_ctx->lsm.cmd_type) {
1115 case LTTCOMM_SESSIOND_COMMAND_CREATE_SESSION_EXT:
1116 case LTTCOMM_SESSIOND_COMMAND_LIST_SESSIONS:
1117 case LTTCOMM_SESSIOND_COMMAND_LIST_TRACEPOINTS:
1118 case LTTCOMM_SESSIOND_COMMAND_LIST_SYSCALLS:
1119 case LTTCOMM_SESSIOND_COMMAND_LIST_TRACEPOINT_FIELDS:
1120 case LTTCOMM_SESSIOND_COMMAND_SAVE_SESSION:
1121 case LTTCOMM_SESSIOND_COMMAND_REGISTER_TRIGGER:
1122 case LTTCOMM_SESSIOND_COMMAND_UNREGISTER_TRIGGER:
1123 case LTTCOMM_SESSIOND_COMMAND_LIST_TRIGGERS:
1124 case LTTCOMM_SESSIOND_COMMAND_EXECUTE_ERROR_QUERY:
1125 need_tracing_session = false;
1126 break;
1127 default:
1128 DBG("Getting session %s by name", cmd_ctx->lsm.session.name);
1129 /*
1130 * We keep the session list lock across _all_ commands
1131 * for now, because the per-session lock does not
1132 * handle teardown properly.
1133 */
1134 session_lock_list();
1135 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm.session.name);
1136 if (cmd_ctx->session == NULL) {
1137 ret = LTTNG_ERR_SESS_NOT_FOUND;
1138 goto error;
1139 } else {
1140 /* Acquire lock for the session */
1141 session_lock(cmd_ctx->session);
1142 }
1143 break;
1144 }
1145
1146 /*
1147 * Commands that need a valid session but should NOT create one if none
1148 * exists. Instead of creating one and destroying it when the command is
1149 * handled, process that right before so we save some round trip in useless
1150 * code path.
1151 */
1152 switch (cmd_ctx->lsm.cmd_type) {
1153 case LTTCOMM_SESSIOND_COMMAND_DISABLE_CHANNEL:
1154 case LTTCOMM_SESSIOND_COMMAND_DISABLE_EVENT:
1155 switch (cmd_ctx->lsm.domain.type) {
1156 case LTTNG_DOMAIN_KERNEL:
1157 if (!cmd_ctx->session->kernel_session) {
1158 ret = LTTNG_ERR_NO_CHANNEL;
1159 goto error;
1160 }
1161 break;
1162 case LTTNG_DOMAIN_JUL:
1163 case LTTNG_DOMAIN_LOG4J:
1164 case LTTNG_DOMAIN_PYTHON:
1165 case LTTNG_DOMAIN_UST:
1166 if (!cmd_ctx->session->ust_session) {
1167 ret = LTTNG_ERR_NO_CHANNEL;
1168 goto error;
1169 }
1170 break;
1171 default:
1172 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1173 goto error;
1174 }
1175 default:
1176 break;
1177 }
1178
1179 if (!need_domain) {
1180 goto skip_domain;
1181 }
1182
1183 /*
1184 * Check domain type for specific "pre-action".
1185 */
1186 switch (cmd_ctx->lsm.domain.type) {
1187 case LTTNG_DOMAIN_KERNEL:
1188 if (!is_root) {
1189 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
1190 goto error;
1191 }
1192
1193 /* Kernel tracer check */
1194 if (!kernel_tracer_is_initialized()) {
1195 /* Basically, load kernel tracer modules */
1196 ret = init_kernel_tracer();
1197 if (ret != 0) {
1198 goto error;
1199 }
1200 }
1201
1202 /* Consumer is in an ERROR state. Report back to client */
1203 if (need_consumerd && uatomic_read(&the_kernel_consumerd_state) ==
1204 CONSUMER_ERROR) {
1205 ret = LTTNG_ERR_NO_KERNCONSUMERD;
1206 goto error;
1207 }
1208
1209 /* Need a session for kernel command */
1210 if (need_tracing_session) {
1211 if (cmd_ctx->session->kernel_session == NULL) {
1212 ret = create_kernel_session(cmd_ctx->session);
1213 if (ret != LTTNG_OK) {
1214 ret = LTTNG_ERR_KERN_SESS_FAIL;
1215 goto error;
1216 }
1217 }
1218
1219 /* Start the kernel consumer daemon */
1220 pthread_mutex_lock(&the_kconsumer_data.pid_mutex);
1221 if (the_kconsumer_data.pid == 0 &&
1222 cmd_ctx->lsm.cmd_type != LTTCOMM_SESSIOND_COMMAND_REGISTER_CONSUMER) {
1223 pthread_mutex_unlock(&the_kconsumer_data.pid_mutex);
1224 ret = start_consumerd(&the_kconsumer_data);
1225 if (ret < 0) {
1226 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
1227 goto error;
1228 }
1229 uatomic_set(&the_kernel_consumerd_state, CONSUMER_STARTED);
1230 } else {
1231 pthread_mutex_unlock(&the_kconsumer_data.pid_mutex);
1232 }
1233
1234 /*
1235 * The consumer was just spawned so we need to add the socket to
1236 * the consumer output of the session if exist.
1237 */
1238 ret = consumer_create_socket(&the_kconsumer_data,
1239 cmd_ctx->session->kernel_session->consumer);
1240 if (ret < 0) {
1241 goto error;
1242 }
1243 }
1244
1245 break;
1246 case LTTNG_DOMAIN_JUL:
1247 case LTTNG_DOMAIN_LOG4J:
1248 case LTTNG_DOMAIN_PYTHON:
1249 if (!agent_tracing_is_enabled()) {
1250 ret = LTTNG_ERR_AGENT_TRACING_DISABLED;
1251 goto error;
1252 }
1253 /* Fallthrough */
1254 case LTTNG_DOMAIN_UST:
1255 {
1256 if (!ust_app_supported()) {
1257 ret = LTTNG_ERR_NO_UST;
1258 goto error;
1259 }
1260
1261 /* Consumer is in an ERROR state. Report back to client */
1262 if (need_consumerd &&
1263 uatomic_read(&the_ust_consumerd_state) ==
1264 CONSUMER_ERROR) {
1265 ret = LTTNG_ERR_NO_USTCONSUMERD;
1266 goto error;
1267 }
1268
1269 if (need_tracing_session) {
1270 /* Create UST session if none exist. */
1271 if (cmd_ctx->session->ust_session == NULL) {
1272 lttng_domain domain = cmd_ctx->lsm.domain;
1273 ret = create_ust_session(cmd_ctx->session, &domain);
1274 if (ret != LTTNG_OK) {
1275 goto error;
1276 }
1277 }
1278
1279 /* Start the UST consumer daemons */
1280 /* 64-bit */
1281 pthread_mutex_lock(&the_ustconsumer64_data.pid_mutex);
1282 if (the_config.consumerd64_bin_path.value &&
1283 the_ustconsumer64_data.pid == 0 &&
1284 cmd_ctx->lsm.cmd_type != LTTCOMM_SESSIOND_COMMAND_REGISTER_CONSUMER) {
1285 pthread_mutex_unlock(&the_ustconsumer64_data.pid_mutex);
1286 ret = start_consumerd(&the_ustconsumer64_data);
1287 if (ret < 0) {
1288 ret = LTTNG_ERR_UST_CONSUMER64_FAIL;
1289 uatomic_set(&the_ust_consumerd64_fd, -EINVAL);
1290 goto error;
1291 }
1292
1293 uatomic_set(&the_ust_consumerd64_fd, the_ustconsumer64_data.cmd_sock);
1294 uatomic_set(&the_ust_consumerd_state, CONSUMER_STARTED);
1295 } else {
1296 pthread_mutex_unlock(&the_ustconsumer64_data.pid_mutex);
1297 }
1298
1299 /*
1300 * Setup socket for consumer 64 bit. No need for atomic access
1301 * since it was set above and can ONLY be set in this thread.
1302 */
1303 ret = consumer_create_socket(&the_ustconsumer64_data,
1304 cmd_ctx->session->ust_session->consumer);
1305 if (ret < 0) {
1306 goto error;
1307 }
1308
1309 /* 32-bit */
1310 pthread_mutex_lock(&the_ustconsumer32_data.pid_mutex);
1311 if (the_config.consumerd32_bin_path.value &&
1312 the_ustconsumer32_data.pid == 0 &&
1313 cmd_ctx->lsm.cmd_type != LTTCOMM_SESSIOND_COMMAND_REGISTER_CONSUMER) {
1314 pthread_mutex_unlock(&the_ustconsumer32_data.pid_mutex);
1315 ret = start_consumerd(&the_ustconsumer32_data);
1316 if (ret < 0) {
1317 ret = LTTNG_ERR_UST_CONSUMER32_FAIL;
1318 uatomic_set(&the_ust_consumerd32_fd, -EINVAL);
1319 goto error;
1320 }
1321
1322 uatomic_set(&the_ust_consumerd32_fd, the_ustconsumer32_data.cmd_sock);
1323 uatomic_set(&the_ust_consumerd_state, CONSUMER_STARTED);
1324 } else {
1325 pthread_mutex_unlock(&the_ustconsumer32_data.pid_mutex);
1326 }
1327
1328 /*
1329 * Setup socket for consumer 32 bit. No need for atomic access
1330 * since it was set above and can ONLY be set in this thread.
1331 */
1332 ret = consumer_create_socket(&the_ustconsumer32_data,
1333 cmd_ctx->session->ust_session->consumer);
1334 if (ret < 0) {
1335 goto error;
1336 }
1337 }
1338 break;
1339 }
1340 default:
1341 break;
1342 }
1343 skip_domain:
1344
1345 /* Validate consumer daemon state when start/stop trace command */
1346 if (cmd_ctx->lsm.cmd_type == LTTCOMM_SESSIOND_COMMAND_START_TRACE ||
1347 cmd_ctx->lsm.cmd_type == LTTCOMM_SESSIOND_COMMAND_STOP_TRACE) {
1348 switch (cmd_ctx->lsm.domain.type) {
1349 case LTTNG_DOMAIN_NONE:
1350 break;
1351 case LTTNG_DOMAIN_JUL:
1352 case LTTNG_DOMAIN_LOG4J:
1353 case LTTNG_DOMAIN_PYTHON:
1354 case LTTNG_DOMAIN_UST:
1355 if (uatomic_read(&the_ust_consumerd_state) != CONSUMER_STARTED) {
1356 ret = LTTNG_ERR_NO_USTCONSUMERD;
1357 goto error;
1358 }
1359 break;
1360 case LTTNG_DOMAIN_KERNEL:
1361 if (uatomic_read(&the_kernel_consumerd_state) != CONSUMER_STARTED) {
1362 ret = LTTNG_ERR_NO_KERNCONSUMERD;
1363 goto error;
1364 }
1365 break;
1366 default:
1367 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1368 goto error;
1369 }
1370 }
1371
1372 /*
1373 * Check that the UID matches that of the tracing session.
1374 * The root user can interact with all sessions.
1375 */
1376 if (need_tracing_session) {
1377 if (!session_access_ok(cmd_ctx->session,
1378 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds)) ||
1379 cmd_ctx->session->destroyed) {
1380 ret = LTTNG_ERR_EPERM;
1381 goto error;
1382 }
1383 }
1384
1385 /*
1386 * Send relayd information to consumer as soon as we have a domain and a
1387 * session defined.
1388 */
1389 if (cmd_ctx->session && need_domain) {
1390 /*
1391 * Setup relayd if not done yet. If the relayd information was already
1392 * sent to the consumer, this call will gracefully return.
1393 */
1394 ret = cmd_setup_relayd(cmd_ctx->session);
1395 if (ret != LTTNG_OK) {
1396 goto error;
1397 }
1398 }
1399
1400 /* Process by command type */
1401 switch (cmd_ctx->lsm.cmd_type) {
1402 case LTTCOMM_SESSIOND_COMMAND_ADD_CONTEXT:
1403 {
1404 struct lttng_event_context *event_context = NULL;
1405 const enum lttng_error_code ret_code =
1406 receive_lttng_event_context(
1407 cmd_ctx, *sock, sock_error, &event_context);
1408
1409 if (ret_code != LTTNG_OK) {
1410 ret = (int) ret_code;
1411 goto error;
1412 }
1413
1414 ret = cmd_add_context(cmd_ctx, event_context, the_kernel_poll_pipe[1]);
1415 lttng_event_context_destroy(event_context);
1416 break;
1417 }
1418 case LTTCOMM_SESSIOND_COMMAND_DISABLE_CHANNEL:
1419 {
1420 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm.domain.type,
1421 cmd_ctx->lsm.u.disable.channel_name);
1422 break;
1423 }
1424 case LTTCOMM_SESSIOND_COMMAND_ENABLE_CHANNEL:
1425 {
1426 ret = cmd_enable_channel(
1427 cmd_ctx, *sock, the_kernel_poll_pipe[1]);
1428 break;
1429 }
1430 case LTTCOMM_SESSIOND_COMMAND_PROCESS_ATTR_TRACKER_ADD_INCLUDE_VALUE:
1431 case LTTCOMM_SESSIOND_COMMAND_PROCESS_ATTR_TRACKER_REMOVE_INCLUDE_VALUE:
1432 {
1433 struct lttng_dynamic_buffer payload;
1434 struct lttng_buffer_view payload_view;
1435 const bool add_value =
1436 cmd_ctx->lsm.cmd_type ==
1437 LTTCOMM_SESSIOND_COMMAND_PROCESS_ATTR_TRACKER_ADD_INCLUDE_VALUE;
1438 const size_t name_len =
1439 cmd_ctx->lsm.u.process_attr_tracker_add_remove_include_value
1440 .name_len;
1441 const enum lttng_domain_type domain_type =
1442 (enum lttng_domain_type)
1443 cmd_ctx->lsm.domain.type;
1444 const enum lttng_process_attr process_attr =
1445 (enum lttng_process_attr) cmd_ctx->lsm.u
1446 .process_attr_tracker_add_remove_include_value
1447 .process_attr;
1448 const enum lttng_process_attr_value_type value_type =
1449 (enum lttng_process_attr_value_type) cmd_ctx
1450 ->lsm.u
1451 .process_attr_tracker_add_remove_include_value
1452 .value_type;
1453 struct process_attr_value *value;
1454 enum lttng_error_code ret_code;
1455 long login_name_max;
1456
1457 login_name_max = sysconf(_SC_LOGIN_NAME_MAX);
1458 if (login_name_max < 0) {
1459 PERROR("Failed to get _SC_LOGIN_NAME_MAX system configuration");
1460 ret = LTTNG_ERR_INVALID;
1461 goto error;
1462 }
1463
1464 /* Receive remaining variable length payload if applicable. */
1465 if (name_len > login_name_max) {
1466 /*
1467 * POSIX mandates user and group names that are at least
1468 * 8 characters long. Note that although shadow-utils
1469 * (useradd, groupaadd, etc.) use 32 chars as their
1470 * limit (from bits/utmp.h, UT_NAMESIZE),
1471 * LOGIN_NAME_MAX is defined to 256.
1472 */
1473 ERR("Rejecting process attribute tracker value %s as the provided exceeds the maximal allowed length: argument length = %zu, maximal length = %ld",
1474 add_value ? "addition" : "removal",
1475 name_len, login_name_max);
1476 ret = LTTNG_ERR_INVALID;
1477 goto error;
1478 }
1479
1480 lttng_dynamic_buffer_init(&payload);
1481 if (name_len != 0) {
1482 /*
1483 * Receive variable payload for user/group name
1484 * arguments.
1485 */
1486 ret = lttng_dynamic_buffer_set_size(&payload, name_len);
1487 if (ret) {
1488 ERR("Failed to allocate buffer to receive payload of %s process attribute tracker value argument",
1489 add_value ? "add" : "remove");
1490 ret = LTTNG_ERR_NOMEM;
1491 goto error_add_remove_tracker_value;
1492 }
1493
1494 ret = lttcomm_recv_unix_sock(
1495 *sock, payload.data, name_len);
1496 if (ret <= 0) {
1497 ERR("Failed to receive payload of %s process attribute tracker value argument",
1498 add_value ? "add" : "remove");
1499 *sock_error = 1;
1500 ret = LTTNG_ERR_INVALID_PROTOCOL;
1501 goto error_add_remove_tracker_value;
1502 }
1503 }
1504
1505 payload_view = lttng_buffer_view_from_dynamic_buffer(
1506 &payload, 0, name_len);
1507 if (name_len > 0 && !lttng_buffer_view_is_valid(&payload_view)) {
1508 ret = LTTNG_ERR_INVALID_PROTOCOL;
1509 goto error_add_remove_tracker_value;
1510 }
1511
1512 /*
1513 * Validate the value type and domains are legal for the process
1514 * attribute tracker that is specified and convert the value to
1515 * add/remove to the internal sessiond representation.
1516 */
1517 ret_code = process_attr_value_from_comm(domain_type,
1518 process_attr, value_type,
1519 &cmd_ctx->lsm.u.process_attr_tracker_add_remove_include_value
1520 .integral_value,
1521 &payload_view, &value);
1522 if (ret_code != LTTNG_OK) {
1523 ret = ret_code;
1524 goto error_add_remove_tracker_value;
1525 }
1526
1527 if (add_value) {
1528 ret = cmd_process_attr_tracker_inclusion_set_add_value(
1529 cmd_ctx->session, domain_type,
1530 process_attr, value);
1531 } else {
1532 ret = cmd_process_attr_tracker_inclusion_set_remove_value(
1533 cmd_ctx->session, domain_type,
1534 process_attr, value);
1535 }
1536 process_attr_value_destroy(value);
1537 error_add_remove_tracker_value:
1538 lttng_dynamic_buffer_reset(&payload);
1539 break;
1540 }
1541 case LTTCOMM_SESSIOND_COMMAND_PROCESS_ATTR_TRACKER_GET_POLICY:
1542 {
1543 enum lttng_tracking_policy tracking_policy;
1544 const enum lttng_domain_type domain_type =
1545 (enum lttng_domain_type)
1546 cmd_ctx->lsm.domain.type;
1547 const enum lttng_process_attr process_attr =
1548 (enum lttng_process_attr) cmd_ctx->lsm.u
1549 .process_attr_tracker_get_tracking_policy
1550 .process_attr;
1551
1552 ret = cmd_process_attr_tracker_get_tracking_policy(
1553 cmd_ctx->session, domain_type, process_attr,
1554 &tracking_policy);
1555 if (ret != LTTNG_OK) {
1556 goto error;
1557 }
1558
1559 uint32_t tracking_policy_u32 = tracking_policy;
1560 ret = setup_lttng_msg_no_cmd_header(cmd_ctx,
1561 &tracking_policy_u32, sizeof(uint32_t));
1562 if (ret < 0) {
1563 ret = LTTNG_ERR_NOMEM;
1564 goto error;
1565 }
1566 ret = LTTNG_OK;
1567 break;
1568 }
1569 case LTTCOMM_SESSIOND_COMMAND_PROCESS_ATTR_TRACKER_SET_POLICY:
1570 {
1571 const enum lttng_tracking_policy tracking_policy =
1572 (enum lttng_tracking_policy) cmd_ctx->lsm.u
1573 .process_attr_tracker_set_tracking_policy
1574 .tracking_policy;
1575 const enum lttng_domain_type domain_type =
1576 (enum lttng_domain_type)
1577 cmd_ctx->lsm.domain.type;
1578 const enum lttng_process_attr process_attr =
1579 (enum lttng_process_attr) cmd_ctx->lsm.u
1580 .process_attr_tracker_set_tracking_policy
1581 .process_attr;
1582
1583 ret = cmd_process_attr_tracker_set_tracking_policy(
1584 cmd_ctx->session, domain_type, process_attr,
1585 tracking_policy);
1586 if (ret != LTTNG_OK) {
1587 goto error;
1588 }
1589 break;
1590 }
1591 case LTTCOMM_SESSIOND_COMMAND_PROCESS_ATTR_TRACKER_GET_INCLUSION_SET:
1592 {
1593 struct lttng_process_attr_values *values;
1594 struct lttng_dynamic_buffer reply;
1595 const enum lttng_domain_type domain_type =
1596 (enum lttng_domain_type)
1597 cmd_ctx->lsm.domain.type;
1598 const enum lttng_process_attr process_attr =
1599 (enum lttng_process_attr) cmd_ctx->lsm.u
1600 .process_attr_tracker_get_inclusion_set
1601 .process_attr;
1602
1603 ret = cmd_process_attr_tracker_get_inclusion_set(
1604 cmd_ctx->session, domain_type, process_attr,
1605 &values);
1606 if (ret != LTTNG_OK) {
1607 goto error;
1608 }
1609
1610 lttng_dynamic_buffer_init(&reply);
1611 ret = lttng_process_attr_values_serialize(values, &reply);
1612 if (ret < 0) {
1613 goto error_tracker_get_inclusion_set;
1614 }
1615
1616 ret = setup_lttng_msg_no_cmd_header(
1617 cmd_ctx, reply.data, reply.size);
1618 if (ret < 0) {
1619 ret = LTTNG_ERR_NOMEM;
1620 goto error_tracker_get_inclusion_set;
1621 }
1622 ret = LTTNG_OK;
1623
1624 error_tracker_get_inclusion_set:
1625 lttng_process_attr_values_destroy(values);
1626 lttng_dynamic_buffer_reset(&reply);
1627 break;
1628 }
1629 case LTTCOMM_SESSIOND_COMMAND_ENABLE_EVENT:
1630 case LTTCOMM_SESSIOND_COMMAND_DISABLE_EVENT:
1631 {
1632 struct lttng_event *event;
1633 char *filter_expression;
1634 struct lttng_event_exclusion *exclusions;
1635 struct lttng_bytecode *bytecode;
1636 const enum lttng_error_code ret_code = receive_lttng_event(
1637 cmd_ctx, *sock, sock_error, &event,
1638 &filter_expression, &bytecode, &exclusions);
1639
1640 if (ret_code != LTTNG_OK) {
1641 ret = (int) ret_code;
1642 goto error;
1643 }
1644
1645 /*
1646 * Ownership of filter_expression, exclusions, and bytecode is
1647 * always transferred.
1648 */
1649 ret = cmd_ctx->lsm.cmd_type == LTTCOMM_SESSIOND_COMMAND_ENABLE_EVENT ?
1650 cmd_enable_event(cmd_ctx, event,
1651 filter_expression, exclusions,
1652 bytecode,
1653 the_kernel_poll_pipe[1]) :
1654 cmd_disable_event(cmd_ctx, event,
1655 filter_expression, bytecode,
1656 exclusions);
1657 lttng_event_destroy(event);
1658 break;
1659 }
1660 case LTTCOMM_SESSIOND_COMMAND_LIST_TRACEPOINTS:
1661 {
1662 enum lttng_error_code ret_code;
1663 size_t original_payload_size;
1664 size_t payload_size;
1665 const size_t command_header_size = sizeof(struct lttcomm_list_command_header);
1666
1667 ret = setup_empty_lttng_msg(cmd_ctx);
1668 if (ret) {
1669 ret = LTTNG_ERR_NOMEM;
1670 goto setup_error;
1671 }
1672
1673 original_payload_size = cmd_ctx->reply_payload.buffer.size;
1674
1675 session_lock_list();
1676 ret_code = cmd_list_tracepoints(cmd_ctx->lsm.domain.type,
1677 &cmd_ctx->reply_payload);
1678 session_unlock_list();
1679 if (ret_code != LTTNG_OK) {
1680 ret = (int) ret_code;
1681 goto error;
1682 }
1683
1684 payload_size = cmd_ctx->reply_payload.buffer.size -
1685 command_header_size - original_payload_size;
1686 update_lttng_msg(cmd_ctx, command_header_size, payload_size);
1687
1688 ret = LTTNG_OK;
1689 break;
1690 }
1691 case LTTCOMM_SESSIOND_COMMAND_LIST_TRACEPOINT_FIELDS:
1692 {
1693 enum lttng_error_code ret_code;
1694 size_t original_payload_size;
1695 size_t payload_size;
1696 const size_t command_header_size = sizeof(struct lttcomm_list_command_header);
1697
1698 ret = setup_empty_lttng_msg(cmd_ctx);
1699 if (ret) {
1700 ret = LTTNG_ERR_NOMEM;
1701 goto setup_error;
1702 }
1703
1704 original_payload_size = cmd_ctx->reply_payload.buffer.size;
1705
1706 session_lock_list();
1707 ret_code = cmd_list_tracepoint_fields(
1708 cmd_ctx->lsm.domain.type, &cmd_ctx->reply_payload);
1709 session_unlock_list();
1710 if (ret_code != LTTNG_OK) {
1711 ret = (int) ret_code;
1712 goto error;
1713 }
1714
1715 payload_size = cmd_ctx->reply_payload.buffer.size -
1716 command_header_size - original_payload_size;
1717 update_lttng_msg(cmd_ctx, command_header_size, payload_size);
1718
1719 ret = LTTNG_OK;
1720 break;
1721 }
1722 case LTTCOMM_SESSIOND_COMMAND_LIST_SYSCALLS:
1723 {
1724 enum lttng_error_code ret_code;
1725 size_t original_payload_size;
1726 size_t payload_size;
1727 const size_t command_header_size = sizeof(struct lttcomm_list_command_header);
1728
1729 ret = setup_empty_lttng_msg(cmd_ctx);
1730 if (ret) {
1731 ret = LTTNG_ERR_NOMEM;
1732 goto setup_error;
1733 }
1734
1735 original_payload_size = cmd_ctx->reply_payload.buffer.size;
1736
1737 ret_code = cmd_list_syscalls(&cmd_ctx->reply_payload);
1738 if (ret_code != LTTNG_OK) {
1739 ret = (int) ret_code;
1740 goto error;
1741 }
1742
1743 payload_size = cmd_ctx->reply_payload.buffer.size -
1744 command_header_size - original_payload_size;
1745 update_lttng_msg(cmd_ctx, command_header_size, payload_size);
1746
1747 ret = LTTNG_OK;
1748 break;
1749 }
1750 case LTTCOMM_SESSIOND_COMMAND_SET_CONSUMER_URI:
1751 {
1752 size_t nb_uri, len;
1753 struct lttng_uri *uris;
1754
1755 nb_uri = cmd_ctx->lsm.u.uri.size;
1756 len = nb_uri * sizeof(struct lttng_uri);
1757
1758 if (nb_uri == 0) {
1759 ret = LTTNG_ERR_INVALID;
1760 goto error;
1761 }
1762
1763 uris = calloc<lttng_uri>(nb_uri);
1764 if (uris == NULL) {
1765 ret = LTTNG_ERR_FATAL;
1766 goto error;
1767 }
1768
1769 /* Receive variable len data */
1770 DBG("Receiving %zu URI(s) from client ...", nb_uri);
1771 ret = lttcomm_recv_unix_sock(*sock, uris, len);
1772 if (ret <= 0) {
1773 DBG("No URIs received from client... continuing");
1774 *sock_error = 1;
1775 ret = LTTNG_ERR_SESSION_FAIL;
1776 free(uris);
1777 goto error;
1778 }
1779
1780 ret = cmd_set_consumer_uri(cmd_ctx->session, nb_uri, uris);
1781 free(uris);
1782 if (ret != LTTNG_OK) {
1783 goto error;
1784 }
1785
1786
1787 break;
1788 }
1789 case LTTCOMM_SESSIOND_COMMAND_START_TRACE:
1790 {
1791 /*
1792 * On the first start, if we have a kernel session and we have
1793 * enabled time or size-based rotations, we have to make sure
1794 * the kernel tracer supports it.
1795 */
1796 if (!cmd_ctx->session->has_been_started && \
1797 cmd_ctx->session->kernel_session && \
1798 (cmd_ctx->session->rotate_timer_period || \
1799 cmd_ctx->session->rotate_size) && \
1800 !check_rotate_compatible()) {
1801 DBG("Kernel tracer version is not compatible with the rotation feature");
1802 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
1803 goto error;
1804 }
1805 ret = cmd_start_trace(cmd_ctx->session);
1806 break;
1807 }
1808 case LTTCOMM_SESSIOND_COMMAND_STOP_TRACE:
1809 {
1810 ret = cmd_stop_trace(cmd_ctx->session);
1811 break;
1812 }
1813 case LTTCOMM_SESSIOND_COMMAND_DESTROY_SESSION:
1814 {
1815 ret = cmd_destroy_session(cmd_ctx->session,
1816 the_notification_thread_handle, sock);
1817 break;
1818 }
1819 case LTTCOMM_SESSIOND_COMMAND_LIST_DOMAINS:
1820 {
1821 ssize_t nb_dom;
1822 struct lttng_domain *domains = NULL;
1823
1824 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
1825 if (nb_dom < 0) {
1826 /* Return value is a negative lttng_error_code. */
1827 ret = -nb_dom;
1828 goto error;
1829 }
1830
1831 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, domains,
1832 nb_dom * sizeof(struct lttng_domain));
1833 free(domains);
1834
1835 if (ret < 0) {
1836 goto setup_error;
1837 }
1838
1839 ret = LTTNG_OK;
1840 break;
1841 }
1842 case LTTCOMM_SESSIOND_COMMAND_LIST_CHANNELS:
1843 {
1844 enum lttng_error_code ret_code;
1845 size_t original_payload_size;
1846 size_t payload_size;
1847 const size_t command_header_size = sizeof(struct lttcomm_list_command_header);
1848
1849 ret = setup_empty_lttng_msg(cmd_ctx);
1850 if (ret) {
1851 ret = LTTNG_ERR_NOMEM;
1852 goto setup_error;
1853 }
1854
1855 original_payload_size = cmd_ctx->reply_payload.buffer.size;
1856
1857 ret_code = cmd_list_channels(cmd_ctx->lsm.domain.type,
1858 cmd_ctx->session, &cmd_ctx->reply_payload);
1859 if (ret_code != LTTNG_OK) {
1860 ret = (int) ret_code;
1861 goto error;
1862 }
1863
1864 payload_size = cmd_ctx->reply_payload.buffer.size -
1865 command_header_size - original_payload_size;
1866 update_lttng_msg(cmd_ctx, command_header_size, payload_size);
1867
1868 ret = LTTNG_OK;
1869 break;
1870 }
1871 case LTTCOMM_SESSIOND_COMMAND_LIST_EVENTS:
1872 {
1873 enum lttng_error_code ret_code;
1874 size_t original_payload_size;
1875 size_t payload_size;
1876 const size_t command_header_size = sizeof(struct lttcomm_list_command_header);
1877
1878 ret = setup_empty_lttng_msg(cmd_ctx);
1879 if (ret) {
1880 ret = LTTNG_ERR_NOMEM;
1881 goto setup_error;
1882 }
1883
1884 original_payload_size = cmd_ctx->reply_payload.buffer.size;
1885
1886 ret_code = cmd_list_events(cmd_ctx->lsm.domain.type,
1887 cmd_ctx->session,
1888 cmd_ctx->lsm.u.list.channel_name, &cmd_ctx->reply_payload);
1889 if (ret_code != LTTNG_OK) {
1890 ret = (int) ret_code;
1891 goto error;
1892 }
1893
1894 payload_size = cmd_ctx->reply_payload.buffer.size -
1895 command_header_size - original_payload_size;
1896 update_lttng_msg(cmd_ctx, command_header_size, payload_size);
1897
1898 ret = LTTNG_OK;
1899 break;
1900 }
1901 case LTTCOMM_SESSIOND_COMMAND_LIST_SESSIONS:
1902 {
1903 unsigned int nr_sessions;
1904 lttng_session *sessions_payload = nullptr;
1905 size_t payload_len = 0;
1906
1907 session_lock_list();
1908 nr_sessions = lttng_sessions_count(
1909 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1910 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
1911
1912 if (nr_sessions > 0) {
1913 payload_len = (sizeof(struct lttng_session) *
1914 nr_sessions) +
1915 (sizeof(struct lttng_session_extended) *
1916 nr_sessions);
1917 sessions_payload = zmalloc<lttng_session>(payload_len);
1918 if (!sessions_payload) {
1919 session_unlock_list();
1920 ret = -ENOMEM;
1921 goto setup_error;
1922 }
1923
1924 cmd_list_lttng_sessions(sessions_payload, nr_sessions,
1925 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1926 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
1927 }
1928
1929 session_unlock_list();
1930
1931 ret = setup_lttng_msg_no_cmd_header(
1932 cmd_ctx, sessions_payload, payload_len);
1933 free(sessions_payload);
1934
1935 if (ret < 0) {
1936 goto setup_error;
1937 }
1938
1939 ret = LTTNG_OK;
1940 break;
1941 }
1942 case LTTCOMM_SESSIOND_COMMAND_REGISTER_CONSUMER:
1943 {
1944 struct consumer_data *cdata;
1945
1946 switch (cmd_ctx->lsm.domain.type) {
1947 case LTTNG_DOMAIN_KERNEL:
1948 cdata = &the_kconsumer_data;
1949 break;
1950 default:
1951 ret = LTTNG_ERR_UND;
1952 goto error;
1953 }
1954
1955 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm.domain.type,
1956 cmd_ctx->lsm.u.reg.path, cdata);
1957 break;
1958 }
1959 case LTTCOMM_SESSIOND_COMMAND_DATA_PENDING:
1960 {
1961 int pending_ret;
1962 uint8_t pending_ret_byte;
1963
1964 pending_ret = cmd_data_pending(cmd_ctx->session);
1965
1966 /*
1967 * FIXME
1968 *
1969 * This function may returns 0 or 1 to indicate whether or not
1970 * there is data pending. In case of error, it should return an
1971 * LTTNG_ERR code. However, some code paths may still return
1972 * a nondescript error code, which we handle by returning an
1973 * "unknown" error.
1974 */
1975 if (pending_ret == 0 || pending_ret == 1) {
1976 /*
1977 * ret will be set to LTTNG_OK at the end of
1978 * this function.
1979 */
1980 } else if (pending_ret < 0) {
1981 ret = LTTNG_ERR_UNK;
1982 goto setup_error;
1983 } else {
1984 ret = pending_ret;
1985 goto setup_error;
1986 }
1987
1988 pending_ret_byte = (uint8_t) pending_ret;
1989
1990 /* 1 byte to return whether or not data is pending */
1991 ret = setup_lttng_msg_no_cmd_header(cmd_ctx,
1992 &pending_ret_byte, 1);
1993
1994 if (ret < 0) {
1995 goto setup_error;
1996 }
1997
1998 ret = LTTNG_OK;
1999 break;
2000 }
2001 case LTTCOMM_SESSIOND_COMMAND_SNAPSHOT_ADD_OUTPUT:
2002 {
2003 uint32_t snapshot_id;
2004 struct lttcomm_lttng_output_id reply;
2005 lttng_snapshot_output output = cmd_ctx->lsm.u.snapshot_output.output;
2006
2007 ret = cmd_snapshot_add_output(cmd_ctx->session,
2008 &output,
2009 &snapshot_id);
2010 if (ret != LTTNG_OK) {
2011 goto error;
2012 }
2013 reply.id = snapshot_id;
2014
2015 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &reply,
2016 sizeof(reply));
2017 if (ret < 0) {
2018 goto setup_error;
2019 }
2020
2021 /* Copy output list into message payload */
2022 ret = LTTNG_OK;
2023 break;
2024 }
2025 case LTTCOMM_SESSIOND_COMMAND_SNAPSHOT_DEL_OUTPUT:
2026 {
2027 lttng_snapshot_output output = cmd_ctx->lsm.u.snapshot_output.output;
2028 ret = cmd_snapshot_del_output(cmd_ctx->session, &output);
2029 break;
2030 }
2031 case LTTCOMM_SESSIOND_COMMAND_SNAPSHOT_LIST_OUTPUT:
2032 {
2033 ssize_t nb_output;
2034 struct lttng_snapshot_output *outputs = NULL;
2035
2036 nb_output = cmd_snapshot_list_outputs(cmd_ctx->session, &outputs);
2037 if (nb_output < 0) {
2038 ret = -nb_output;
2039 goto error;
2040 }
2041
2042 LTTNG_ASSERT((nb_output > 0 && outputs) || nb_output == 0);
2043 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, outputs,
2044 nb_output * sizeof(struct lttng_snapshot_output));
2045 free(outputs);
2046
2047 if (ret < 0) {
2048 goto setup_error;
2049 }
2050
2051 ret = LTTNG_OK;
2052 break;
2053 }
2054 case LTTCOMM_SESSIOND_COMMAND_SNAPSHOT_RECORD:
2055 {
2056 lttng_snapshot_output output = cmd_ctx->lsm.u.snapshot_record.output;
2057 ret = cmd_snapshot_record(cmd_ctx->session,
2058 &output, 0); // RFC: set to zero since it's ignored by cmd_snapshot_record
2059 break;
2060 }
2061 case LTTCOMM_SESSIOND_COMMAND_CREATE_SESSION_EXT:
2062 {
2063 struct lttng_dynamic_buffer payload;
2064 struct lttng_session_descriptor *return_descriptor = NULL;
2065
2066 lttng_dynamic_buffer_init(&payload);
2067 ret = cmd_create_session(cmd_ctx, *sock, &return_descriptor);
2068 if (ret != LTTNG_OK) {
2069 goto error;
2070 }
2071
2072 ret = lttng_session_descriptor_serialize(return_descriptor,
2073 &payload);
2074 if (ret) {
2075 ERR("Failed to serialize session descriptor in reply to \"create session\" command");
2076 lttng_session_descriptor_destroy(return_descriptor);
2077 ret = LTTNG_ERR_NOMEM;
2078 goto error;
2079 }
2080 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, payload.data,
2081 payload.size);
2082 if (ret) {
2083 lttng_session_descriptor_destroy(return_descriptor);
2084 ret = LTTNG_ERR_NOMEM;
2085 goto error;
2086 }
2087 lttng_dynamic_buffer_reset(&payload);
2088 lttng_session_descriptor_destroy(return_descriptor);
2089 ret = LTTNG_OK;
2090 break;
2091 }
2092 case LTTCOMM_SESSIOND_COMMAND_SAVE_SESSION:
2093 {
2094 ret = cmd_save_sessions(&cmd_ctx->lsm.u.save_session.attr,
2095 &cmd_ctx->creds);
2096 break;
2097 }
2098 case LTTCOMM_SESSIOND_COMMAND_SET_SESSION_SHM_PATH:
2099 {
2100 ret = cmd_set_session_shm_path(cmd_ctx->session,
2101 cmd_ctx->lsm.u.set_shm_path.shm_path);
2102 break;
2103 }
2104 case LTTCOMM_SESSIOND_COMMAND_REGENERATE_METADATA:
2105 {
2106 ret = cmd_regenerate_metadata(cmd_ctx->session);
2107 break;
2108 }
2109 case LTTCOMM_SESSIOND_COMMAND_REGENERATE_STATEDUMP:
2110 {
2111 ret = cmd_regenerate_statedump(cmd_ctx->session);
2112 break;
2113 }
2114 case LTTCOMM_SESSIOND_COMMAND_REGISTER_TRIGGER:
2115 {
2116 struct lttng_trigger *payload_trigger;
2117 struct lttng_trigger *return_trigger;
2118 size_t original_reply_payload_size;
2119 size_t reply_payload_size;
2120 const struct lttng_credentials cmd_creds = {
2121 .uid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.uid),
2122 .gid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.gid),
2123 };
2124
2125 ret = setup_empty_lttng_msg(cmd_ctx);
2126 if (ret) {
2127 ret = LTTNG_ERR_NOMEM;
2128 goto setup_error;
2129 }
2130
2131 ret = receive_lttng_trigger(
2132 cmd_ctx, *sock, sock_error, &payload_trigger);
2133 if (ret != LTTNG_OK) {
2134 goto error;
2135 }
2136
2137 original_reply_payload_size = cmd_ctx->reply_payload.buffer.size;
2138
2139 ret = cmd_register_trigger(&cmd_creds, payload_trigger,
2140 cmd_ctx->lsm.u.trigger.is_trigger_anonymous,
2141 the_notification_thread_handle,
2142 &return_trigger);
2143 if (ret != LTTNG_OK) {
2144 lttng_trigger_put(payload_trigger);
2145 goto error;
2146 }
2147
2148 ret = lttng_trigger_serialize(return_trigger, &cmd_ctx->reply_payload);
2149 lttng_trigger_put(payload_trigger);
2150 lttng_trigger_put(return_trigger);
2151 if (ret) {
2152 ERR("Failed to serialize trigger in reply to \"register trigger\" command");
2153 ret = LTTNG_ERR_NOMEM;
2154 goto error;
2155 }
2156
2157 reply_payload_size = cmd_ctx->reply_payload.buffer.size -
2158 original_reply_payload_size;
2159
2160 update_lttng_msg(cmd_ctx, 0, reply_payload_size);
2161
2162 ret = LTTNG_OK;
2163 break;
2164 }
2165 case LTTCOMM_SESSIOND_COMMAND_UNREGISTER_TRIGGER:
2166 {
2167 struct lttng_trigger *payload_trigger;
2168 const struct lttng_credentials cmd_creds = {
2169 .uid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.uid),
2170 .gid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.gid),
2171 };
2172
2173 ret = receive_lttng_trigger(
2174 cmd_ctx, *sock, sock_error, &payload_trigger);
2175 if (ret != LTTNG_OK) {
2176 goto error;
2177 }
2178
2179 ret = cmd_unregister_trigger(&cmd_creds, payload_trigger,
2180 the_notification_thread_handle);
2181 lttng_trigger_put(payload_trigger);
2182 break;
2183 }
2184 case LTTCOMM_SESSIOND_COMMAND_ROTATE_SESSION:
2185 {
2186 struct lttng_rotate_session_return rotate_return;
2187
2188 DBG("Client rotate session \"%s\"", cmd_ctx->session->name);
2189
2190 memset(&rotate_return, 0, sizeof(rotate_return));
2191 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
2192 DBG("Kernel tracer version is not compatible with the rotation feature");
2193 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
2194 goto error;
2195 }
2196
2197 ret = cmd_rotate_session(cmd_ctx->session, &rotate_return,
2198 false,
2199 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
2200 if (ret < 0) {
2201 ret = -ret;
2202 goto error;
2203 }
2204
2205 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &rotate_return,
2206 sizeof(rotate_return));
2207 if (ret < 0) {
2208 ret = -ret;
2209 goto error;
2210 }
2211
2212 ret = LTTNG_OK;
2213 break;
2214 }
2215 case LTTCOMM_SESSIOND_COMMAND_ROTATION_GET_INFO:
2216 {
2217 struct lttng_rotation_get_info_return get_info_return;
2218
2219 memset(&get_info_return, 0, sizeof(get_info_return));
2220 ret = cmd_rotate_get_info(cmd_ctx->session, &get_info_return,
2221 cmd_ctx->lsm.u.get_rotation_info.rotation_id);
2222 if (ret < 0) {
2223 ret = -ret;
2224 goto error;
2225 }
2226
2227 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &get_info_return,
2228 sizeof(get_info_return));
2229 if (ret < 0) {
2230 ret = -ret;
2231 goto error;
2232 }
2233
2234 ret = LTTNG_OK;
2235 break;
2236 }
2237 case LTTCOMM_SESSIOND_COMMAND_ROTATION_SET_SCHEDULE:
2238 {
2239 bool set_schedule;
2240 enum lttng_rotation_schedule_type schedule_type;
2241 uint64_t value;
2242
2243 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
2244 DBG("Kernel tracer version does not support session rotations");
2245 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
2246 goto error;
2247 }
2248
2249 set_schedule = cmd_ctx->lsm.u.rotation_set_schedule.set == 1;
2250 schedule_type = (enum lttng_rotation_schedule_type) cmd_ctx->lsm.u.rotation_set_schedule.type;
2251 value = cmd_ctx->lsm.u.rotation_set_schedule.value;
2252
2253 ret = cmd_rotation_set_schedule(cmd_ctx->session, set_schedule,
2254 schedule_type, value,
2255 the_notification_thread_handle);
2256 if (ret != LTTNG_OK) {
2257 goto error;
2258 }
2259
2260 break;
2261 }
2262 case LTTCOMM_SESSIOND_COMMAND_SESSION_LIST_ROTATION_SCHEDULES:
2263 {
2264 lttng_session_list_schedules_return schedules;
2265
2266 schedules.periodic.set = !!cmd_ctx->session->rotate_timer_period;
2267 schedules.periodic.value = cmd_ctx->session->rotate_timer_period;
2268 schedules.size.set = !!cmd_ctx->session->rotate_size;
2269 schedules.size.value = cmd_ctx->session->rotate_size;
2270
2271 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &schedules,
2272 sizeof(schedules));
2273 if (ret < 0) {
2274 ret = -ret;
2275 goto error;
2276 }
2277
2278 ret = LTTNG_OK;
2279 break;
2280 }
2281 case LTTCOMM_SESSIOND_COMMAND_CLEAR_SESSION:
2282 {
2283 ret = cmd_clear_session(cmd_ctx->session, sock);
2284 break;
2285 }
2286 case LTTCOMM_SESSIOND_COMMAND_LIST_TRIGGERS:
2287 {
2288 struct lttng_triggers *return_triggers = NULL;
2289 size_t original_payload_size;
2290 size_t payload_size;
2291
2292 ret = setup_empty_lttng_msg(cmd_ctx);
2293 if (ret) {
2294 ret = LTTNG_ERR_NOMEM;
2295 goto setup_error;
2296 }
2297
2298 original_payload_size = cmd_ctx->reply_payload.buffer.size;
2299
2300 ret = cmd_list_triggers(cmd_ctx, the_notification_thread_handle,
2301 &return_triggers);
2302 if (ret != LTTNG_OK) {
2303 goto error;
2304 }
2305
2306 LTTNG_ASSERT(return_triggers);
2307 ret = lttng_triggers_serialize(
2308 return_triggers, &cmd_ctx->reply_payload);
2309 lttng_triggers_destroy(return_triggers);
2310 if (ret) {
2311 ERR("Failed to serialize triggers in reply to `list triggers` command");
2312 ret = LTTNG_ERR_NOMEM;
2313 goto error;
2314 }
2315
2316 payload_size = cmd_ctx->reply_payload.buffer.size -
2317 original_payload_size;
2318
2319 update_lttng_msg(cmd_ctx, 0, payload_size);
2320
2321 ret = LTTNG_OK;
2322 break;
2323 }
2324 case LTTCOMM_SESSIOND_COMMAND_EXECUTE_ERROR_QUERY:
2325 {
2326 struct lttng_error_query *query;
2327 const struct lttng_credentials cmd_creds = {
2328 .uid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.uid),
2329 .gid = LTTNG_OPTIONAL_INIT_VALUE(cmd_ctx->creds.gid),
2330 };
2331 struct lttng_error_query_results *results = NULL;
2332 size_t original_payload_size;
2333 size_t payload_size;
2334
2335 ret = setup_empty_lttng_msg(cmd_ctx);
2336 if (ret) {
2337 ret = LTTNG_ERR_NOMEM;
2338 goto setup_error;
2339 }
2340
2341 original_payload_size = cmd_ctx->reply_payload.buffer.size;
2342
2343 ret = receive_lttng_error_query(
2344 cmd_ctx, *sock, sock_error, &query);
2345 if (ret != LTTNG_OK) {
2346 goto error;
2347 }
2348
2349 ret = cmd_execute_error_query(&cmd_creds, query, &results,
2350 the_notification_thread_handle);
2351 lttng_error_query_destroy(query);
2352 if (ret != LTTNG_OK) {
2353 goto error;
2354 }
2355
2356 LTTNG_ASSERT(results);
2357 ret = lttng_error_query_results_serialize(
2358 results, &cmd_ctx->reply_payload);
2359 lttng_error_query_results_destroy(results);
2360 if (ret) {
2361 ERR("Failed to serialize error query result set in reply to `execute error query` command");
2362 ret = LTTNG_ERR_NOMEM;
2363 goto error;
2364 }
2365
2366 payload_size = cmd_ctx->reply_payload.buffer.size -
2367 original_payload_size;
2368
2369 update_lttng_msg(cmd_ctx, 0, payload_size);
2370
2371 ret = LTTNG_OK;
2372
2373 break;
2374 }
2375 default:
2376 ret = LTTNG_ERR_UND;
2377 break;
2378 }
2379
2380 error:
2381 if (cmd_ctx->reply_payload.buffer.size == 0) {
2382 DBG("Missing llm header, creating one.");
2383 if (setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0) < 0) {
2384 goto setup_error;
2385 }
2386 }
2387 /* Set return code */
2388 ((struct lttcomm_lttng_msg *) (cmd_ctx->reply_payload.buffer.data))->ret_code = ret;
2389 setup_error:
2390 if (cmd_ctx->session) {
2391 session_unlock(cmd_ctx->session);
2392 session_put(cmd_ctx->session);
2393 cmd_ctx->session = NULL;
2394 }
2395 if (need_tracing_session) {
2396 session_unlock_list();
2397 }
2398 init_setup_error:
2399 LTTNG_ASSERT(!rcu_read_ongoing());
2400 return ret;
2401 }
2402
2403 static int create_client_sock(void)
2404 {
2405 int ret, client_sock;
2406
2407 /* Create client tool unix socket */
2408 client_sock = lttcomm_create_unix_sock(
2409 the_config.client_unix_sock_path.value);
2410 if (client_sock < 0) {
2411 ERR("Create unix sock failed: %s",
2412 the_config.client_unix_sock_path.value);
2413 ret = -1;
2414 goto end;
2415 }
2416
2417 /* Set the cloexec flag */
2418 ret = utils_set_fd_cloexec(client_sock);
2419 if (ret < 0) {
2420 ERR("Unable to set CLOEXEC flag to the client Unix socket (fd: %d). "
2421 "Continuing but note that the consumer daemon will have a "
2422 "reference to this socket on exec()", client_sock);
2423 }
2424
2425 /* File permission MUST be 660 */
2426 ret = chmod(the_config.client_unix_sock_path.value,
2427 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
2428 if (ret < 0) {
2429 ERR("Set file permissions failed: %s",
2430 the_config.client_unix_sock_path.value);
2431 PERROR("chmod");
2432 (void) lttcomm_close_unix_sock(client_sock);
2433 ret = -1;
2434 goto end;
2435 }
2436 DBG("Created client socket (fd = %i)", client_sock);
2437 ret = client_sock;
2438 end:
2439 return ret;
2440 }
2441
2442 static void cleanup_client_thread(void *data)
2443 {
2444 struct lttng_pipe *quit_pipe = (lttng_pipe *) data;
2445
2446 lttng_pipe_destroy(quit_pipe);
2447 }
2448
2449 static void thread_init_cleanup(void *data __attribute__((unused)))
2450 {
2451 set_thread_status(false);
2452 }
2453
2454 /*
2455 * This thread manage all clients request using the unix client socket for
2456 * communication.
2457 */
2458 static void *thread_manage_clients(void *data)
2459 {
2460 int sock = -1, ret, i, err = -1;
2461 int sock_error;
2462 uint32_t nb_fd;
2463 struct lttng_poll_event events;
2464 const int client_sock = thread_state.client_sock;
2465 struct lttng_pipe *quit_pipe = (lttng_pipe *) data;
2466 const int thread_quit_pipe_fd = lttng_pipe_get_readfd(quit_pipe);
2467 struct command_ctx cmd_ctx = {};
2468
2469 DBG("[thread] Manage client started");
2470
2471 lttng_payload_init(&cmd_ctx.reply_payload);
2472
2473 is_root = (getuid() == 0);
2474
2475 pthread_cleanup_push(thread_init_cleanup, NULL);
2476
2477 rcu_register_thread();
2478
2479 health_register(the_health_sessiond, HEALTH_SESSIOND_TYPE_CMD);
2480
2481 health_code_update();
2482
2483 ret = lttcomm_listen_unix_sock(client_sock);
2484 if (ret < 0) {
2485 goto error_listen;
2486 }
2487
2488 /*
2489 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2490 * more will be added to this poll set.
2491 */
2492 ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
2493 if (ret < 0) {
2494 goto error_create_poll;
2495 }
2496
2497 /* Add the application registration socket */
2498 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
2499 if (ret < 0) {
2500 goto error;
2501 }
2502
2503 /* Add thread quit pipe */
2504 ret = lttng_poll_add(&events, thread_quit_pipe_fd, LPOLLIN | LPOLLERR);
2505 if (ret < 0) {
2506 goto error;
2507 }
2508
2509 /* Set state as running. */
2510 set_thread_status(true);
2511 pthread_cleanup_pop(0);
2512
2513 /* This testpoint is after we signal readiness to the parent. */
2514 if (testpoint(sessiond_thread_manage_clients)) {
2515 goto error;
2516 }
2517
2518 if (testpoint(sessiond_thread_manage_clients_before_loop)) {
2519 goto error;
2520 }
2521
2522 health_code_update();
2523
2524 while (1) {
2525 const struct cmd_completion_handler *cmd_completion_handler;
2526
2527 cmd_ctx.creds.uid = UINT32_MAX;
2528 cmd_ctx.creds.gid = UINT32_MAX;
2529 cmd_ctx.creds.pid = 0;
2530 cmd_ctx.session = NULL;
2531 lttng_payload_clear(&cmd_ctx.reply_payload);
2532 cmd_ctx.lttng_msg_size = 0;
2533
2534 DBG("Accepting client command ...");
2535
2536 /* Inifinite blocking call, waiting for transmission */
2537 restart:
2538 health_poll_entry();
2539 ret = lttng_poll_wait(&events, -1);
2540 health_poll_exit();
2541 if (ret < 0) {
2542 /*
2543 * Restart interrupted system call.
2544 */
2545 if (errno == EINTR) {
2546 goto restart;
2547 }
2548 goto error;
2549 }
2550
2551 nb_fd = ret;
2552
2553 for (i = 0; i < nb_fd; i++) {
2554 /* Fetch once the poll data. */
2555 const auto revents = LTTNG_POLL_GETEV(&events, i);
2556 const auto pollfd = LTTNG_POLL_GETFD(&events, i);
2557
2558 health_code_update();
2559
2560 /* Activity on thread quit pipe, exiting. */
2561 if (pollfd == thread_quit_pipe_fd) {
2562 DBG("Activity on thread quit pipe");
2563 err = 0;
2564 goto exit;
2565 }
2566
2567 /* Event on the registration socket */
2568 if (revents & LPOLLIN) {
2569 continue;
2570 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2571 ERR("Client socket poll error");
2572 goto error;
2573 } else {
2574 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
2575 goto error;
2576 }
2577 }
2578
2579 DBG("Wait for client response");
2580
2581 health_code_update();
2582
2583 sock = lttcomm_accept_unix_sock(client_sock);
2584 if (sock < 0) {
2585 goto error;
2586 }
2587
2588 /*
2589 * Set the CLOEXEC flag. Return code is useless because either way, the
2590 * show must go on.
2591 */
2592 (void) utils_set_fd_cloexec(sock);
2593
2594 /* Set socket option for credentials retrieval */
2595 ret = lttcomm_setsockopt_creds_unix_sock(sock);
2596 if (ret < 0) {
2597 goto error;
2598 }
2599
2600 health_code_update();
2601
2602 /*
2603 * Data is received from the lttng client. The struct
2604 * lttcomm_session_msg (lsm) contains the command and data request of
2605 * the client.
2606 */
2607 DBG("Receiving data from client ...");
2608 ret = lttcomm_recv_creds_unix_sock(sock, &cmd_ctx.lsm,
2609 sizeof(struct lttcomm_session_msg), &cmd_ctx.creds);
2610 if (ret != sizeof(struct lttcomm_session_msg)) {
2611 DBG("Incomplete recv() from client... continuing");
2612 ret = close(sock);
2613 if (ret) {
2614 PERROR("close");
2615 }
2616 sock = -1;
2617 continue;
2618 }
2619
2620 health_code_update();
2621
2622 // TODO: Validate cmd_ctx including sanity check for
2623 // security purpose.
2624
2625 rcu_thread_online();
2626 /*
2627 * This function dispatch the work to the kernel or userspace tracer
2628 * libs and fill the lttcomm_lttng_msg data structure of all the needed
2629 * informations for the client. The command context struct contains
2630 * everything this function may needs.
2631 */
2632 ret = process_client_msg(&cmd_ctx, &sock, &sock_error);
2633 rcu_thread_offline();
2634 if (ret < 0) {
2635 if (sock >= 0) {
2636 ret = close(sock);
2637 if (ret) {
2638 PERROR("close");
2639 }
2640 }
2641 sock = -1;
2642 /*
2643 * TODO: Inform client somehow of the fatal error. At
2644 * this point, ret < 0 means that a zmalloc failed
2645 * (ENOMEM). Error detected but still accept
2646 * command, unless a socket error has been
2647 * detected.
2648 */
2649 continue;
2650 }
2651
2652 if (ret < LTTNG_OK || ret >= LTTNG_ERR_NR) {
2653 WARN("Command returned an invalid status code, returning unknown error: "
2654 "command type = %s (%d), ret = %d",
2655 lttcomm_sessiond_command_str((lttcomm_sessiond_command) cmd_ctx.lsm.cmd_type),
2656 cmd_ctx.lsm.cmd_type, ret);
2657 ret = LTTNG_ERR_UNK;
2658 }
2659
2660 cmd_completion_handler = cmd_pop_completion_handler();
2661 if (cmd_completion_handler) {
2662 enum lttng_error_code completion_code;
2663
2664 completion_code = cmd_completion_handler->run(
2665 cmd_completion_handler->data);
2666 if (completion_code != LTTNG_OK) {
2667 continue;
2668 }
2669 }
2670
2671 health_code_update();
2672
2673 if (sock >= 0) {
2674 struct lttng_payload_view view =
2675 lttng_payload_view_from_payload(
2676 &cmd_ctx.reply_payload,
2677 0, -1);
2678 struct lttcomm_lttng_msg *llm = (typeof(
2679 llm)) cmd_ctx.reply_payload.buffer.data;
2680
2681 LTTNG_ASSERT(cmd_ctx.reply_payload.buffer.size >= sizeof(*llm));
2682 LTTNG_ASSERT(cmd_ctx.lttng_msg_size == cmd_ctx.reply_payload.buffer.size);
2683
2684 llm->fd_count = lttng_payload_view_get_fd_handle_count(&view);
2685
2686 DBG("Sending response (size: %d, retcode: %s (%d))",
2687 cmd_ctx.lttng_msg_size,
2688 lttng_strerror(-llm->ret_code),
2689 llm->ret_code);
2690 ret = send_unix_sock(sock, &view);
2691 if (ret < 0) {
2692 ERR("Failed to send data back to client");
2693 }
2694
2695 /* End of transmission */
2696 ret = close(sock);
2697 if (ret) {
2698 PERROR("close");
2699 }
2700 }
2701 sock = -1;
2702
2703 health_code_update();
2704 }
2705
2706 exit:
2707 error:
2708 if (sock >= 0) {
2709 ret = close(sock);
2710 if (ret) {
2711 PERROR("close");
2712 }
2713 }
2714
2715 lttng_poll_clean(&events);
2716
2717 error_listen:
2718 error_create_poll:
2719 unlink(the_config.client_unix_sock_path.value);
2720 ret = close(client_sock);
2721 if (ret) {
2722 PERROR("close");
2723 }
2724
2725 if (err) {
2726 health_error();
2727 ERR("Health error occurred in %s", __func__);
2728 }
2729
2730 health_unregister(the_health_sessiond);
2731
2732 DBG("Client thread dying");
2733 lttng_payload_reset(&cmd_ctx.reply_payload);
2734 rcu_unregister_thread();
2735 return NULL;
2736 }
2737
2738 static
2739 bool shutdown_client_thread(void *thread_data)
2740 {
2741 struct lttng_pipe *client_quit_pipe = (lttng_pipe *) thread_data;
2742 const int write_fd = lttng_pipe_get_writefd(client_quit_pipe);
2743
2744 return notify_thread_pipe(write_fd) == 1;
2745 }
2746
2747 struct lttng_thread *launch_client_thread(void)
2748 {
2749 bool thread_running;
2750 struct lttng_pipe *client_quit_pipe;
2751 struct lttng_thread *thread = NULL;
2752 int client_sock_fd = -1;
2753
2754 sem_init(&thread_state.ready, 0, 0);
2755 client_quit_pipe = lttng_pipe_open(FD_CLOEXEC);
2756 if (!client_quit_pipe) {
2757 goto error;
2758 }
2759
2760 client_sock_fd = create_client_sock();
2761 if (client_sock_fd < 0) {
2762 goto error;
2763 }
2764
2765 thread_state.client_sock = client_sock_fd;
2766 thread = lttng_thread_create("Client management",
2767 thread_manage_clients,
2768 shutdown_client_thread,
2769 cleanup_client_thread,
2770 client_quit_pipe);
2771 if (!thread) {
2772 goto error;
2773 }
2774 /* The client thread now owns the client sock fd and the quit pipe. */
2775 client_sock_fd = -1;
2776 client_quit_pipe = NULL;
2777
2778 /*
2779 * This thread is part of the threads that need to be fully
2780 * initialized before the session daemon is marked as "ready".
2781 */
2782 thread_running = wait_thread_status();
2783 if (!thread_running) {
2784 goto error;
2785 }
2786 return thread;
2787 error:
2788 if (client_sock_fd >= 0) {
2789 if (close(client_sock_fd)) {
2790 PERROR("Failed to close client socket");
2791 }
2792 }
2793 lttng_thread_put(thread);
2794 cleanup_client_thread(client_quit_pipe);
2795 return NULL;
2796 }
LTTng 2.0 tools and control repository
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