d7db03fa76981f38ac60b3eb9e78579c9512fa4b
[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 /*
698 * Version of setup_lttng_msg() without command header.
699 */
700 static int setup_lttng_msg_no_cmd_header(struct command_ctx *cmd_ctx,
701 void *payload_buf, size_t payload_len)
702 {
703 return setup_lttng_msg(cmd_ctx, payload_buf, payload_len, NULL, 0);
704 }
705
706 /*
707 * Check if the current kernel tracer supports the session rotation feature.
708 * Return 1 if it does, 0 otherwise.
709 */
710 static int check_rotate_compatible(void)
711 {
712 int ret = 1;
713
714 if (kernel_tracer_version.major != 2 || kernel_tracer_version.minor < 11) {
715 DBG("Kernel tracer version is not compatible with the rotation feature");
716 ret = 0;
717 }
718
719 return ret;
720 }
721
722 /*
723 * Send data on a unix socket using the liblttsessiondcomm API.
724 *
725 * Return lttcomm error code.
726 */
727 static int send_unix_sock(int sock, struct lttng_payload_view *view)
728 {
729 int ret;
730 const int fd_count = lttng_payload_view_get_fd_handle_count(view);
731
732 /* Check valid length */
733 if (view->buffer.size == 0) {
734 ret = -1;
735 goto end;
736 }
737
738 ret = lttcomm_send_unix_sock(
739 sock, view->buffer.data, view->buffer.size);
740 if (ret < 0) {
741 goto end;
742 }
743
744 if (fd_count > 0) {
745 ret = lttcomm_send_payload_view_fds_unix_sock(sock, view);
746 if (ret < 0) {
747 goto end;
748 }
749 }
750
751 end:
752 return ret;
753 }
754
755 /*
756 * Process the command requested by the lttng client within the command
757 * context structure. This function make sure that the return structure (llm)
758 * is set and ready for transmission before returning.
759 *
760 * Return any error encountered or 0 for success.
761 *
762 * "sock" is only used for special-case var. len data.
763 * A command may assume the ownership of the socket, in which case its value
764 * should be set to -1.
765 *
766 * Should *NOT* be called with RCU read-side lock held.
767 */
768 static int process_client_msg(struct command_ctx *cmd_ctx, int *sock,
769 int *sock_error)
770 {
771 int ret = LTTNG_OK;
772 int need_tracing_session = 1;
773 int need_domain;
774
775 DBG("Processing client command %d", cmd_ctx->lsm.cmd_type);
776
777 assert(!rcu_read_ongoing());
778
779 *sock_error = 0;
780
781 switch (cmd_ctx->lsm.cmd_type) {
782 case LTTNG_CREATE_SESSION_EXT:
783 case LTTNG_DESTROY_SESSION:
784 case LTTNG_LIST_SESSIONS:
785 case LTTNG_LIST_DOMAINS:
786 case LTTNG_START_TRACE:
787 case LTTNG_STOP_TRACE:
788 case LTTNG_DATA_PENDING:
789 case LTTNG_SNAPSHOT_ADD_OUTPUT:
790 case LTTNG_SNAPSHOT_DEL_OUTPUT:
791 case LTTNG_SNAPSHOT_LIST_OUTPUT:
792 case LTTNG_SNAPSHOT_RECORD:
793 case LTTNG_SAVE_SESSION:
794 case LTTNG_SET_SESSION_SHM_PATH:
795 case LTTNG_REGENERATE_METADATA:
796 case LTTNG_REGENERATE_STATEDUMP:
797 case LTTNG_REGISTER_TRIGGER:
798 case LTTNG_UNREGISTER_TRIGGER:
799 case LTTNG_ROTATE_SESSION:
800 case LTTNG_ROTATION_GET_INFO:
801 case LTTNG_ROTATION_SET_SCHEDULE:
802 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
803 case LTTNG_CLEAR_SESSION:
804 need_domain = 0;
805 break;
806 default:
807 need_domain = 1;
808 }
809
810 if (config.no_kernel && need_domain
811 && cmd_ctx->lsm.domain.type == LTTNG_DOMAIN_KERNEL) {
812 if (!is_root) {
813 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
814 } else {
815 ret = LTTNG_ERR_KERN_NA;
816 }
817 goto error;
818 }
819
820 /* Deny register consumer if we already have a spawned consumer. */
821 if (cmd_ctx->lsm.cmd_type == LTTNG_REGISTER_CONSUMER) {
822 pthread_mutex_lock(&kconsumer_data.pid_mutex);
823 if (kconsumer_data.pid > 0) {
824 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
825 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
826 goto error;
827 }
828 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
829 }
830
831 /*
832 * Check for command that don't needs to allocate a returned payload. We do
833 * this here so we don't have to make the call for no payload at each
834 * command.
835 */
836 switch(cmd_ctx->lsm.cmd_type) {
837 case LTTNG_LIST_SESSIONS:
838 case LTTNG_LIST_TRACEPOINTS:
839 case LTTNG_LIST_TRACEPOINT_FIELDS:
840 case LTTNG_LIST_DOMAINS:
841 case LTTNG_LIST_CHANNELS:
842 case LTTNG_LIST_EVENTS:
843 case LTTNG_LIST_SYSCALLS:
844 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
845 case LTTNG_PROCESS_ATTR_TRACKER_GET_POLICY:
846 case LTTNG_PROCESS_ATTR_TRACKER_GET_INCLUSION_SET:
847 case LTTNG_DATA_PENDING:
848 case LTTNG_ROTATE_SESSION:
849 case LTTNG_ROTATION_GET_INFO:
850 break;
851 default:
852 /* Setup lttng message with no payload */
853 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0);
854 if (ret < 0) {
855 /* This label does not try to unlock the session */
856 goto init_setup_error;
857 }
858 }
859
860 /* Commands that DO NOT need a session. */
861 switch (cmd_ctx->lsm.cmd_type) {
862 case LTTNG_CREATE_SESSION_EXT:
863 case LTTNG_LIST_SESSIONS:
864 case LTTNG_LIST_TRACEPOINTS:
865 case LTTNG_LIST_SYSCALLS:
866 case LTTNG_LIST_TRACEPOINT_FIELDS:
867 case LTTNG_SAVE_SESSION:
868 case LTTNG_REGISTER_TRIGGER:
869 case LTTNG_UNREGISTER_TRIGGER:
870 need_tracing_session = 0;
871 break;
872 default:
873 DBG("Getting session %s by name", cmd_ctx->lsm.session.name);
874 /*
875 * We keep the session list lock across _all_ commands
876 * for now, because the per-session lock does not
877 * handle teardown properly.
878 */
879 session_lock_list();
880 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm.session.name);
881 if (cmd_ctx->session == NULL) {
882 ret = LTTNG_ERR_SESS_NOT_FOUND;
883 goto error;
884 } else {
885 /* Acquire lock for the session */
886 session_lock(cmd_ctx->session);
887 }
888 break;
889 }
890
891 /*
892 * Commands that need a valid session but should NOT create one if none
893 * exists. Instead of creating one and destroying it when the command is
894 * handled, process that right before so we save some round trip in useless
895 * code path.
896 */
897 switch (cmd_ctx->lsm.cmd_type) {
898 case LTTNG_DISABLE_CHANNEL:
899 case LTTNG_DISABLE_EVENT:
900 switch (cmd_ctx->lsm.domain.type) {
901 case LTTNG_DOMAIN_KERNEL:
902 if (!cmd_ctx->session->kernel_session) {
903 ret = LTTNG_ERR_NO_CHANNEL;
904 goto error;
905 }
906 break;
907 case LTTNG_DOMAIN_JUL:
908 case LTTNG_DOMAIN_LOG4J:
909 case LTTNG_DOMAIN_PYTHON:
910 case LTTNG_DOMAIN_UST:
911 if (!cmd_ctx->session->ust_session) {
912 ret = LTTNG_ERR_NO_CHANNEL;
913 goto error;
914 }
915 break;
916 default:
917 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
918 goto error;
919 }
920 default:
921 break;
922 }
923
924 if (!need_domain) {
925 goto skip_domain;
926 }
927
928 /*
929 * Check domain type for specific "pre-action".
930 */
931 switch (cmd_ctx->lsm.domain.type) {
932 case LTTNG_DOMAIN_KERNEL:
933 if (!is_root) {
934 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
935 goto error;
936 }
937
938 /* Kernel tracer check */
939 if (!kernel_tracer_is_initialized()) {
940 /* Basically, load kernel tracer modules */
941 ret = init_kernel_tracer();
942 if (ret != 0) {
943 goto error;
944 }
945 }
946
947 /* Consumer is in an ERROR state. Report back to client */
948 if (uatomic_read(&kernel_consumerd_state) == CONSUMER_ERROR) {
949 ret = LTTNG_ERR_NO_KERNCONSUMERD;
950 goto error;
951 }
952
953 /* Need a session for kernel command */
954 if (need_tracing_session) {
955 if (cmd_ctx->session->kernel_session == NULL) {
956 ret = create_kernel_session(cmd_ctx->session);
957 if (ret != LTTNG_OK) {
958 ret = LTTNG_ERR_KERN_SESS_FAIL;
959 goto error;
960 }
961 }
962
963 /* Start the kernel consumer daemon */
964 pthread_mutex_lock(&kconsumer_data.pid_mutex);
965 if (kconsumer_data.pid == 0 &&
966 cmd_ctx->lsm.cmd_type != LTTNG_REGISTER_CONSUMER) {
967 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
968 ret = start_consumerd(&kconsumer_data);
969 if (ret < 0) {
970 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
971 goto error;
972 }
973 uatomic_set(&kernel_consumerd_state, CONSUMER_STARTED);
974 } else {
975 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
976 }
977
978 /*
979 * The consumer was just spawned so we need to add the socket to
980 * the consumer output of the session if exist.
981 */
982 ret = consumer_create_socket(&kconsumer_data,
983 cmd_ctx->session->kernel_session->consumer);
984 if (ret < 0) {
985 goto error;
986 }
987 }
988
989 break;
990 case LTTNG_DOMAIN_JUL:
991 case LTTNG_DOMAIN_LOG4J:
992 case LTTNG_DOMAIN_PYTHON:
993 case LTTNG_DOMAIN_UST:
994 {
995 if (!ust_app_supported()) {
996 ret = LTTNG_ERR_NO_UST;
997 goto error;
998 }
999 /* Consumer is in an ERROR state. Report back to client */
1000 if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) {
1001 ret = LTTNG_ERR_NO_USTCONSUMERD;
1002 goto error;
1003 }
1004
1005 if (need_tracing_session) {
1006 /* Create UST session if none exist. */
1007 if (cmd_ctx->session->ust_session == NULL) {
1008 ret = create_ust_session(cmd_ctx->session,
1009 ALIGNED_CONST_PTR(cmd_ctx->lsm.domain));
1010 if (ret != LTTNG_OK) {
1011 goto error;
1012 }
1013 }
1014
1015 /* Start the UST consumer daemons */
1016 /* 64-bit */
1017 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
1018 if (config.consumerd64_bin_path.value &&
1019 ustconsumer64_data.pid == 0 &&
1020 cmd_ctx->lsm.cmd_type != LTTNG_REGISTER_CONSUMER) {
1021 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
1022 ret = start_consumerd(&ustconsumer64_data);
1023 if (ret < 0) {
1024 ret = LTTNG_ERR_UST_CONSUMER64_FAIL;
1025 uatomic_set(&ust_consumerd64_fd, -EINVAL);
1026 goto error;
1027 }
1028
1029 uatomic_set(&ust_consumerd64_fd, ustconsumer64_data.cmd_sock);
1030 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
1031 } else {
1032 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
1033 }
1034
1035 /*
1036 * Setup socket for consumer 64 bit. No need for atomic access
1037 * since it was set above and can ONLY be set in this thread.
1038 */
1039 ret = consumer_create_socket(&ustconsumer64_data,
1040 cmd_ctx->session->ust_session->consumer);
1041 if (ret < 0) {
1042 goto error;
1043 }
1044
1045 /* 32-bit */
1046 pthread_mutex_lock(&ustconsumer32_data.pid_mutex);
1047 if (config.consumerd32_bin_path.value &&
1048 ustconsumer32_data.pid == 0 &&
1049 cmd_ctx->lsm.cmd_type != LTTNG_REGISTER_CONSUMER) {
1050 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
1051 ret = start_consumerd(&ustconsumer32_data);
1052 if (ret < 0) {
1053 ret = LTTNG_ERR_UST_CONSUMER32_FAIL;
1054 uatomic_set(&ust_consumerd32_fd, -EINVAL);
1055 goto error;
1056 }
1057
1058 uatomic_set(&ust_consumerd32_fd, ustconsumer32_data.cmd_sock);
1059 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
1060 } else {
1061 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
1062 }
1063
1064 /*
1065 * Setup socket for consumer 32 bit. No need for atomic access
1066 * since it was set above and can ONLY be set in this thread.
1067 */
1068 ret = consumer_create_socket(&ustconsumer32_data,
1069 cmd_ctx->session->ust_session->consumer);
1070 if (ret < 0) {
1071 goto error;
1072 }
1073 }
1074 break;
1075 }
1076 default:
1077 break;
1078 }
1079 skip_domain:
1080
1081 /* Validate consumer daemon state when start/stop trace command */
1082 if (cmd_ctx->lsm.cmd_type == LTTNG_START_TRACE ||
1083 cmd_ctx->lsm.cmd_type == LTTNG_STOP_TRACE) {
1084 switch (cmd_ctx->lsm.domain.type) {
1085 case LTTNG_DOMAIN_NONE:
1086 break;
1087 case LTTNG_DOMAIN_JUL:
1088 case LTTNG_DOMAIN_LOG4J:
1089 case LTTNG_DOMAIN_PYTHON:
1090 case LTTNG_DOMAIN_UST:
1091 if (uatomic_read(&ust_consumerd_state) != CONSUMER_STARTED) {
1092 ret = LTTNG_ERR_NO_USTCONSUMERD;
1093 goto error;
1094 }
1095 break;
1096 case LTTNG_DOMAIN_KERNEL:
1097 if (uatomic_read(&kernel_consumerd_state) != CONSUMER_STARTED) {
1098 ret = LTTNG_ERR_NO_KERNCONSUMERD;
1099 goto error;
1100 }
1101 break;
1102 default:
1103 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1104 goto error;
1105 }
1106 }
1107
1108 /*
1109 * Check that the UID matches that of the tracing session.
1110 * The root user can interact with all sessions.
1111 */
1112 if (need_tracing_session) {
1113 if (!session_access_ok(cmd_ctx->session,
1114 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds)) ||
1115 cmd_ctx->session->destroyed) {
1116 ret = LTTNG_ERR_EPERM;
1117 goto error;
1118 }
1119 }
1120
1121 /*
1122 * Send relayd information to consumer as soon as we have a domain and a
1123 * session defined.
1124 */
1125 if (cmd_ctx->session && need_domain) {
1126 /*
1127 * Setup relayd if not done yet. If the relayd information was already
1128 * sent to the consumer, this call will gracefully return.
1129 */
1130 ret = cmd_setup_relayd(cmd_ctx->session);
1131 if (ret != LTTNG_OK) {
1132 goto error;
1133 }
1134 }
1135
1136 /* Process by command type */
1137 switch (cmd_ctx->lsm.cmd_type) {
1138 case LTTNG_ADD_CONTEXT:
1139 {
1140 /*
1141 * An LTTNG_ADD_CONTEXT command might have a supplementary
1142 * payload if the context being added is an application context.
1143 */
1144 if (cmd_ctx->lsm.u.context.ctx.ctx ==
1145 LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1146 char *provider_name = NULL, *context_name = NULL;
1147 size_t provider_name_len =
1148 cmd_ctx->lsm.u.context.provider_name_len;
1149 size_t context_name_len =
1150 cmd_ctx->lsm.u.context.context_name_len;
1151
1152 if (provider_name_len == 0 || context_name_len == 0) {
1153 /*
1154 * Application provider and context names MUST
1155 * be provided.
1156 */
1157 ret = -LTTNG_ERR_INVALID;
1158 goto error;
1159 }
1160
1161 provider_name = zmalloc(provider_name_len + 1);
1162 if (!provider_name) {
1163 ret = -LTTNG_ERR_NOMEM;
1164 goto error;
1165 }
1166 cmd_ctx->lsm.u.context.ctx.u.app_ctx.provider_name =
1167 provider_name;
1168
1169 context_name = zmalloc(context_name_len + 1);
1170 if (!context_name) {
1171 ret = -LTTNG_ERR_NOMEM;
1172 goto error_add_context;
1173 }
1174 cmd_ctx->lsm.u.context.ctx.u.app_ctx.ctx_name =
1175 context_name;
1176
1177 ret = lttcomm_recv_unix_sock(*sock, provider_name,
1178 provider_name_len);
1179 if (ret < 0) {
1180 goto error_add_context;
1181 }
1182
1183 ret = lttcomm_recv_unix_sock(*sock, context_name,
1184 context_name_len);
1185 if (ret < 0) {
1186 goto error_add_context;
1187 }
1188 }
1189
1190 /*
1191 * cmd_add_context assumes ownership of the provider and context
1192 * names.
1193 */
1194 ret = cmd_add_context(cmd_ctx->session,
1195 cmd_ctx->lsm.domain.type,
1196 cmd_ctx->lsm.u.context.channel_name,
1197 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.context.ctx),
1198 kernel_poll_pipe[1]);
1199
1200 cmd_ctx->lsm.u.context.ctx.u.app_ctx.provider_name = NULL;
1201 cmd_ctx->lsm.u.context.ctx.u.app_ctx.ctx_name = NULL;
1202 error_add_context:
1203 free(cmd_ctx->lsm.u.context.ctx.u.app_ctx.provider_name);
1204 free(cmd_ctx->lsm.u.context.ctx.u.app_ctx.ctx_name);
1205 if (ret < 0) {
1206 goto error;
1207 }
1208 break;
1209 }
1210 case LTTNG_DISABLE_CHANNEL:
1211 {
1212 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm.domain.type,
1213 cmd_ctx->lsm.u.disable.channel_name);
1214 break;
1215 }
1216 case LTTNG_DISABLE_EVENT:
1217 {
1218
1219 /*
1220 * FIXME: handle filter; for now we just receive the filter's
1221 * bytecode along with the filter expression which are sent by
1222 * liblttng-ctl and discard them.
1223 *
1224 * This fixes an issue where the client may block while sending
1225 * the filter payload and encounter an error because the session
1226 * daemon closes the socket without ever handling this data.
1227 */
1228 size_t count = cmd_ctx->lsm.u.disable.expression_len +
1229 cmd_ctx->lsm.u.disable.bytecode_len;
1230
1231 if (count) {
1232 char data[LTTNG_FILTER_MAX_LEN];
1233
1234 DBG("Discarding disable event command payload of size %zu", count);
1235 while (count) {
1236 ret = lttcomm_recv_unix_sock(*sock, data,
1237 count > sizeof(data) ? sizeof(data) : count);
1238 if (ret < 0) {
1239 goto error;
1240 }
1241
1242 count -= (size_t) ret;
1243 }
1244 }
1245 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm.domain.type,
1246 cmd_ctx->lsm.u.disable.channel_name,
1247 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.disable.event));
1248 break;
1249 }
1250 case LTTNG_ENABLE_CHANNEL:
1251 {
1252 cmd_ctx->lsm.u.channel.chan.attr.extended.ptr =
1253 (struct lttng_channel_extended *) &cmd_ctx->lsm.u.channel.extended;
1254 ret = cmd_enable_channel(cmd_ctx->session,
1255 ALIGNED_CONST_PTR(cmd_ctx->lsm.domain),
1256 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.channel.chan),
1257 kernel_poll_pipe[1]);
1258 break;
1259 }
1260 case LTTNG_PROCESS_ATTR_TRACKER_ADD_INCLUDE_VALUE:
1261 case LTTNG_PROCESS_ATTR_TRACKER_REMOVE_INCLUDE_VALUE:
1262 {
1263 struct lttng_dynamic_buffer payload;
1264 struct lttng_buffer_view payload_view;
1265 const bool add_value =
1266 cmd_ctx->lsm.cmd_type ==
1267 LTTNG_PROCESS_ATTR_TRACKER_ADD_INCLUDE_VALUE;
1268 const size_t name_len =
1269 cmd_ctx->lsm.u.process_attr_tracker_add_remove_include_value
1270 .name_len;
1271 const enum lttng_domain_type domain_type =
1272 (enum lttng_domain_type)
1273 cmd_ctx->lsm.domain.type;
1274 const enum lttng_process_attr process_attr =
1275 (enum lttng_process_attr) cmd_ctx->lsm.u
1276 .process_attr_tracker_add_remove_include_value
1277 .process_attr;
1278 const enum lttng_process_attr_value_type value_type =
1279 (enum lttng_process_attr_value_type) cmd_ctx
1280 ->lsm.u
1281 .process_attr_tracker_add_remove_include_value
1282 .value_type;
1283 struct process_attr_value *value;
1284 enum lttng_error_code ret_code;
1285 long login_name_max;
1286
1287 login_name_max = sysconf(_SC_LOGIN_NAME_MAX);
1288 if (login_name_max < 0) {
1289 PERROR("Failed to get _SC_LOGIN_NAME_MAX system configuration");
1290 ret = LTTNG_ERR_INVALID;
1291 goto error;
1292 }
1293
1294 /* Receive remaining variable length payload if applicable. */
1295 if (name_len > login_name_max) {
1296 /*
1297 * POSIX mandates user and group names that are at least
1298 * 8 characters long. Note that although shadow-utils
1299 * (useradd, groupaadd, etc.) use 32 chars as their
1300 * limit (from bits/utmp.h, UT_NAMESIZE),
1301 * LOGIN_NAME_MAX is defined to 256.
1302 */
1303 ERR("Rejecting process attribute tracker value %s as the provided exceeds the maximal allowed length: argument length = %zu, maximal length = %ld",
1304 add_value ? "addition" : "removal",
1305 name_len, login_name_max);
1306 ret = LTTNG_ERR_INVALID;
1307 goto error;
1308 }
1309
1310 lttng_dynamic_buffer_init(&payload);
1311 if (name_len != 0) {
1312 /*
1313 * Receive variable payload for user/group name
1314 * arguments.
1315 */
1316 ret = lttng_dynamic_buffer_set_size(&payload, name_len);
1317 if (ret) {
1318 ERR("Failed to allocate buffer to receive payload of %s process attribute tracker value argument",
1319 add_value ? "add" : "remove");
1320 ret = LTTNG_ERR_NOMEM;
1321 goto error_add_remove_tracker_value;
1322 }
1323
1324 ret = lttcomm_recv_unix_sock(
1325 *sock, payload.data, name_len);
1326 if (ret <= 0) {
1327 ERR("Failed to receive payload of %s process attribute tracker value argument",
1328 add_value ? "add" : "remove");
1329 *sock_error = 1;
1330 ret = LTTNG_ERR_INVALID_PROTOCOL;
1331 goto error_add_remove_tracker_value;
1332 }
1333 }
1334
1335 payload_view = lttng_buffer_view_from_dynamic_buffer(
1336 &payload, 0, name_len);
1337 /*
1338 * Validate the value type and domains are legal for the process
1339 * attribute tracker that is specified and convert the value to
1340 * add/remove to the internal sessiond representation.
1341 */
1342 ret_code = process_attr_value_from_comm(domain_type,
1343 process_attr, value_type,
1344 &cmd_ctx->lsm.u.process_attr_tracker_add_remove_include_value
1345 .integral_value,
1346 &payload_view, &value);
1347 if (ret_code != LTTNG_OK) {
1348 ret = ret_code;
1349 goto error_add_remove_tracker_value;
1350 }
1351
1352 if (add_value) {
1353 ret = cmd_process_attr_tracker_inclusion_set_add_value(
1354 cmd_ctx->session, domain_type,
1355 process_attr, value);
1356 } else {
1357 ret = cmd_process_attr_tracker_inclusion_set_remove_value(
1358 cmd_ctx->session, domain_type,
1359 process_attr, value);
1360 }
1361 process_attr_value_destroy(value);
1362 error_add_remove_tracker_value:
1363 lttng_dynamic_buffer_reset(&payload);
1364 break;
1365 }
1366 case LTTNG_PROCESS_ATTR_TRACKER_GET_POLICY:
1367 {
1368 enum lttng_tracking_policy tracking_policy;
1369 const enum lttng_domain_type domain_type =
1370 (enum lttng_domain_type)
1371 cmd_ctx->lsm.domain.type;
1372 const enum lttng_process_attr process_attr =
1373 (enum lttng_process_attr) cmd_ctx->lsm.u
1374 .process_attr_tracker_get_tracking_policy
1375 .process_attr;
1376
1377 ret = cmd_process_attr_tracker_get_tracking_policy(
1378 cmd_ctx->session, domain_type, process_attr,
1379 &tracking_policy);
1380 if (ret != LTTNG_OK) {
1381 goto error;
1382 }
1383
1384 ret = setup_lttng_msg_no_cmd_header(cmd_ctx,
1385 &(uint32_t){tracking_policy}, sizeof(uint32_t));
1386 if (ret < 0) {
1387 ret = LTTNG_ERR_NOMEM;
1388 goto error;
1389 }
1390 ret = LTTNG_OK;
1391 break;
1392 }
1393 case LTTNG_PROCESS_ATTR_TRACKER_SET_POLICY:
1394 {
1395 const enum lttng_tracking_policy tracking_policy =
1396 (enum lttng_tracking_policy) cmd_ctx->lsm.u
1397 .process_attr_tracker_set_tracking_policy
1398 .tracking_policy;
1399 const enum lttng_domain_type domain_type =
1400 (enum lttng_domain_type)
1401 cmd_ctx->lsm.domain.type;
1402 const enum lttng_process_attr process_attr =
1403 (enum lttng_process_attr) cmd_ctx->lsm.u
1404 .process_attr_tracker_set_tracking_policy
1405 .process_attr;
1406
1407 ret = cmd_process_attr_tracker_set_tracking_policy(
1408 cmd_ctx->session, domain_type, process_attr,
1409 tracking_policy);
1410 if (ret != LTTNG_OK) {
1411 goto error;
1412 }
1413 break;
1414 }
1415 case LTTNG_PROCESS_ATTR_TRACKER_GET_INCLUSION_SET:
1416 {
1417 struct lttng_process_attr_values *values;
1418 struct lttng_dynamic_buffer reply;
1419 const enum lttng_domain_type domain_type =
1420 (enum lttng_domain_type)
1421 cmd_ctx->lsm.domain.type;
1422 const enum lttng_process_attr process_attr =
1423 (enum lttng_process_attr) cmd_ctx->lsm.u
1424 .process_attr_tracker_get_inclusion_set
1425 .process_attr;
1426
1427 ret = cmd_process_attr_tracker_get_inclusion_set(
1428 cmd_ctx->session, domain_type, process_attr,
1429 &values);
1430 if (ret != LTTNG_OK) {
1431 goto error;
1432 }
1433
1434 lttng_dynamic_buffer_init(&reply);
1435 ret = lttng_process_attr_values_serialize(values, &reply);
1436 if (ret < 0) {
1437 goto error_tracker_get_inclusion_set;
1438 }
1439
1440 ret = setup_lttng_msg_no_cmd_header(
1441 cmd_ctx, reply.data, reply.size);
1442 if (ret < 0) {
1443 ret = LTTNG_ERR_NOMEM;
1444 goto error_tracker_get_inclusion_set;
1445 }
1446 ret = LTTNG_OK;
1447
1448 error_tracker_get_inclusion_set:
1449 lttng_process_attr_values_destroy(values);
1450 lttng_dynamic_buffer_reset(&reply);
1451 break;
1452 }
1453 case LTTNG_ENABLE_EVENT:
1454 {
1455 struct lttng_event *ev = NULL;
1456 struct lttng_event_exclusion *exclusion = NULL;
1457 struct lttng_filter_bytecode *bytecode = NULL;
1458 char *filter_expression = NULL;
1459
1460 /* Handle exclusion events and receive it from the client. */
1461 if (cmd_ctx->lsm.u.enable.exclusion_count > 0) {
1462 size_t count = cmd_ctx->lsm.u.enable.exclusion_count;
1463
1464 exclusion = zmalloc(sizeof(struct lttng_event_exclusion) +
1465 (count * LTTNG_SYMBOL_NAME_LEN));
1466 if (!exclusion) {
1467 ret = LTTNG_ERR_EXCLUSION_NOMEM;
1468 goto error;
1469 }
1470
1471 DBG("Receiving var len exclusion event list from client ...");
1472 exclusion->count = count;
1473 ret = lttcomm_recv_unix_sock(*sock, exclusion->names,
1474 count * LTTNG_SYMBOL_NAME_LEN);
1475 if (ret <= 0) {
1476 DBG("Nothing recv() from client var len data... continuing");
1477 *sock_error = 1;
1478 free(exclusion);
1479 ret = LTTNG_ERR_EXCLUSION_INVAL;
1480 goto error;
1481 }
1482 }
1483
1484 /* Get filter expression from client. */
1485 if (cmd_ctx->lsm.u.enable.expression_len > 0) {
1486 size_t expression_len =
1487 cmd_ctx->lsm.u.enable.expression_len;
1488
1489 if (expression_len > LTTNG_FILTER_MAX_LEN) {
1490 ret = LTTNG_ERR_FILTER_INVAL;
1491 free(exclusion);
1492 goto error;
1493 }
1494
1495 filter_expression = zmalloc(expression_len);
1496 if (!filter_expression) {
1497 free(exclusion);
1498 ret = LTTNG_ERR_FILTER_NOMEM;
1499 goto error;
1500 }
1501
1502 /* Receive var. len. data */
1503 DBG("Receiving var len filter's expression from client ...");
1504 ret = lttcomm_recv_unix_sock(*sock, filter_expression,
1505 expression_len);
1506 if (ret <= 0) {
1507 DBG("Nothing recv() from client var len data... continuing");
1508 *sock_error = 1;
1509 free(filter_expression);
1510 free(exclusion);
1511 ret = LTTNG_ERR_FILTER_INVAL;
1512 goto error;
1513 }
1514 }
1515
1516 /* Handle filter and get bytecode from client. */
1517 if (cmd_ctx->lsm.u.enable.bytecode_len > 0) {
1518 size_t bytecode_len = cmd_ctx->lsm.u.enable.bytecode_len;
1519
1520 if (bytecode_len > LTTNG_FILTER_MAX_LEN) {
1521 ret = LTTNG_ERR_FILTER_INVAL;
1522 free(filter_expression);
1523 free(exclusion);
1524 goto error;
1525 }
1526
1527 bytecode = zmalloc(bytecode_len);
1528 if (!bytecode) {
1529 free(filter_expression);
1530 free(exclusion);
1531 ret = LTTNG_ERR_FILTER_NOMEM;
1532 goto error;
1533 }
1534
1535 /* Receive var. len. data */
1536 DBG("Receiving var len filter's bytecode from client ...");
1537 ret = lttcomm_recv_unix_sock(*sock, bytecode, bytecode_len);
1538 if (ret <= 0) {
1539 DBG("Nothing recv() from client var len data... continuing");
1540 *sock_error = 1;
1541 free(filter_expression);
1542 free(bytecode);
1543 free(exclusion);
1544 ret = LTTNG_ERR_FILTER_INVAL;
1545 goto error;
1546 }
1547
1548 if ((bytecode->len + sizeof(*bytecode)) != bytecode_len) {
1549 free(filter_expression);
1550 free(bytecode);
1551 free(exclusion);
1552 ret = LTTNG_ERR_FILTER_INVAL;
1553 goto error;
1554 }
1555 }
1556
1557 ev = lttng_event_copy(ALIGNED_CONST_PTR(cmd_ctx->lsm.u.enable.event));
1558 if (!ev) {
1559 DBG("Failed to copy event: %s",
1560 cmd_ctx->lsm.u.enable.event.name);
1561 free(filter_expression);
1562 free(bytecode);
1563 free(exclusion);
1564 ret = LTTNG_ERR_NOMEM;
1565 goto error;
1566 }
1567
1568
1569 if (cmd_ctx->lsm.u.enable.userspace_probe_location_len > 0) {
1570 /* Expect a userspace probe description. */
1571 ret = receive_userspace_probe(cmd_ctx, *sock, sock_error, ev);
1572 if (ret) {
1573 free(filter_expression);
1574 free(bytecode);
1575 free(exclusion);
1576 lttng_event_destroy(ev);
1577 goto error;
1578 }
1579 }
1580
1581 ret = cmd_enable_event(cmd_ctx->session,
1582 ALIGNED_CONST_PTR(cmd_ctx->lsm.domain),
1583 cmd_ctx->lsm.u.enable.channel_name,
1584 ev,
1585 filter_expression, bytecode, exclusion,
1586 kernel_poll_pipe[1]);
1587 lttng_event_destroy(ev);
1588 break;
1589 }
1590 case LTTNG_LIST_TRACEPOINTS:
1591 {
1592 struct lttng_event *events;
1593 ssize_t nb_events;
1594
1595 session_lock_list();
1596 nb_events = cmd_list_tracepoints(cmd_ctx->lsm.domain.type, &events);
1597 session_unlock_list();
1598 if (nb_events < 0) {
1599 /* Return value is a negative lttng_error_code. */
1600 ret = -nb_events;
1601 goto error;
1602 }
1603
1604 /*
1605 * Setup lttng message with payload size set to the event list size in
1606 * bytes and then copy list into the llm payload.
1607 */
1608 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, events,
1609 sizeof(struct lttng_event) * nb_events);
1610 free(events);
1611
1612 if (ret < 0) {
1613 goto setup_error;
1614 }
1615
1616 ret = LTTNG_OK;
1617 break;
1618 }
1619 case LTTNG_LIST_TRACEPOINT_FIELDS:
1620 {
1621 struct lttng_event_field *fields;
1622 ssize_t nb_fields;
1623
1624 session_lock_list();
1625 nb_fields = cmd_list_tracepoint_fields(cmd_ctx->lsm.domain.type,
1626 &fields);
1627 session_unlock_list();
1628 if (nb_fields < 0) {
1629 /* Return value is a negative lttng_error_code. */
1630 ret = -nb_fields;
1631 goto error;
1632 }
1633
1634 /*
1635 * Setup lttng message with payload size set to the event list size in
1636 * bytes and then copy list into the llm payload.
1637 */
1638 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, fields,
1639 sizeof(struct lttng_event_field) * nb_fields);
1640 free(fields);
1641
1642 if (ret < 0) {
1643 goto setup_error;
1644 }
1645
1646 ret = LTTNG_OK;
1647 break;
1648 }
1649 case LTTNG_LIST_SYSCALLS:
1650 {
1651 struct lttng_event *events;
1652 ssize_t nb_events;
1653
1654 nb_events = cmd_list_syscalls(&events);
1655 if (nb_events < 0) {
1656 /* Return value is a negative lttng_error_code. */
1657 ret = -nb_events;
1658 goto error;
1659 }
1660
1661 /*
1662 * Setup lttng message with payload size set to the event list size in
1663 * bytes and then copy list into the llm payload.
1664 */
1665 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, events,
1666 sizeof(struct lttng_event) * nb_events);
1667 free(events);
1668
1669 if (ret < 0) {
1670 goto setup_error;
1671 }
1672
1673 ret = LTTNG_OK;
1674 break;
1675 }
1676 case LTTNG_SET_CONSUMER_URI:
1677 {
1678 size_t nb_uri, len;
1679 struct lttng_uri *uris;
1680
1681 nb_uri = cmd_ctx->lsm.u.uri.size;
1682 len = nb_uri * sizeof(struct lttng_uri);
1683
1684 if (nb_uri == 0) {
1685 ret = LTTNG_ERR_INVALID;
1686 goto error;
1687 }
1688
1689 uris = zmalloc(len);
1690 if (uris == NULL) {
1691 ret = LTTNG_ERR_FATAL;
1692 goto error;
1693 }
1694
1695 /* Receive variable len data */
1696 DBG("Receiving %zu URI(s) from client ...", nb_uri);
1697 ret = lttcomm_recv_unix_sock(*sock, uris, len);
1698 if (ret <= 0) {
1699 DBG("No URIs received from client... continuing");
1700 *sock_error = 1;
1701 ret = LTTNG_ERR_SESSION_FAIL;
1702 free(uris);
1703 goto error;
1704 }
1705
1706 ret = cmd_set_consumer_uri(cmd_ctx->session, nb_uri, uris);
1707 free(uris);
1708 if (ret != LTTNG_OK) {
1709 goto error;
1710 }
1711
1712
1713 break;
1714 }
1715 case LTTNG_START_TRACE:
1716 {
1717 /*
1718 * On the first start, if we have a kernel session and we have
1719 * enabled time or size-based rotations, we have to make sure
1720 * the kernel tracer supports it.
1721 */
1722 if (!cmd_ctx->session->has_been_started && \
1723 cmd_ctx->session->kernel_session && \
1724 (cmd_ctx->session->rotate_timer_period || \
1725 cmd_ctx->session->rotate_size) && \
1726 !check_rotate_compatible()) {
1727 DBG("Kernel tracer version is not compatible with the rotation feature");
1728 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
1729 goto error;
1730 }
1731 ret = cmd_start_trace(cmd_ctx->session);
1732 break;
1733 }
1734 case LTTNG_STOP_TRACE:
1735 {
1736 ret = cmd_stop_trace(cmd_ctx->session);
1737 break;
1738 }
1739 case LTTNG_DESTROY_SESSION:
1740 {
1741 ret = cmd_destroy_session(cmd_ctx->session,
1742 notification_thread_handle,
1743 sock);
1744 break;
1745 }
1746 case LTTNG_LIST_DOMAINS:
1747 {
1748 ssize_t nb_dom;
1749 struct lttng_domain *domains = NULL;
1750
1751 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
1752 if (nb_dom < 0) {
1753 /* Return value is a negative lttng_error_code. */
1754 ret = -nb_dom;
1755 goto error;
1756 }
1757
1758 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, domains,
1759 nb_dom * sizeof(struct lttng_domain));
1760 free(domains);
1761
1762 if (ret < 0) {
1763 goto setup_error;
1764 }
1765
1766 ret = LTTNG_OK;
1767 break;
1768 }
1769 case LTTNG_LIST_CHANNELS:
1770 {
1771 ssize_t payload_size;
1772 struct lttng_channel *channels = NULL;
1773
1774 payload_size = cmd_list_channels(cmd_ctx->lsm.domain.type,
1775 cmd_ctx->session, &channels);
1776 if (payload_size < 0) {
1777 /* Return value is a negative lttng_error_code. */
1778 ret = -payload_size;
1779 goto error;
1780 }
1781
1782 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, channels,
1783 payload_size);
1784 free(channels);
1785
1786 if (ret < 0) {
1787 goto setup_error;
1788 }
1789
1790 ret = LTTNG_OK;
1791 break;
1792 }
1793 case LTTNG_LIST_EVENTS:
1794 {
1795 ssize_t list_ret;
1796 struct lttcomm_event_command_header cmd_header = {};
1797 size_t original_payload_size;
1798 size_t payload_size;
1799
1800 ret = setup_empty_lttng_msg(cmd_ctx);
1801 if (ret) {
1802 ret = LTTNG_ERR_NOMEM;
1803 goto setup_error;
1804 }
1805
1806 original_payload_size = cmd_ctx->reply_payload.buffer.size;
1807
1808 /* Extended infos are included at the end of the payload. */
1809 list_ret = cmd_list_events(cmd_ctx->lsm.domain.type,
1810 cmd_ctx->session,
1811 cmd_ctx->lsm.u.list.channel_name,
1812 &cmd_ctx->reply_payload);
1813 if (list_ret < 0) {
1814 /* Return value is a negative lttng_error_code. */
1815 ret = -list_ret;
1816 goto error;
1817 }
1818
1819 payload_size = cmd_ctx->reply_payload.buffer.size -
1820 sizeof(cmd_header) - original_payload_size;
1821 update_lttng_msg(cmd_ctx, sizeof(cmd_header), payload_size);
1822
1823 ret = LTTNG_OK;
1824 break;
1825 }
1826 case LTTNG_LIST_SESSIONS:
1827 {
1828 unsigned int nr_sessions;
1829 void *sessions_payload;
1830 size_t payload_len;
1831
1832 session_lock_list();
1833 nr_sessions = lttng_sessions_count(
1834 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1835 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
1836
1837 payload_len = (sizeof(struct lttng_session) * nr_sessions) +
1838 (sizeof(struct lttng_session_extended) * nr_sessions);
1839 sessions_payload = zmalloc(payload_len);
1840
1841 if (!sessions_payload) {
1842 session_unlock_list();
1843 ret = -ENOMEM;
1844 goto setup_error;
1845 }
1846
1847 cmd_list_lttng_sessions(sessions_payload, nr_sessions,
1848 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1849 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
1850 session_unlock_list();
1851
1852 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, sessions_payload,
1853 payload_len);
1854 free(sessions_payload);
1855
1856 if (ret < 0) {
1857 goto setup_error;
1858 }
1859
1860 ret = LTTNG_OK;
1861 break;
1862 }
1863 case LTTNG_REGISTER_CONSUMER:
1864 {
1865 struct consumer_data *cdata;
1866
1867 switch (cmd_ctx->lsm.domain.type) {
1868 case LTTNG_DOMAIN_KERNEL:
1869 cdata = &kconsumer_data;
1870 break;
1871 default:
1872 ret = LTTNG_ERR_UND;
1873 goto error;
1874 }
1875
1876 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm.domain.type,
1877 cmd_ctx->lsm.u.reg.path, cdata);
1878 break;
1879 }
1880 case LTTNG_DATA_PENDING:
1881 {
1882 int pending_ret;
1883 uint8_t pending_ret_byte;
1884
1885 pending_ret = cmd_data_pending(cmd_ctx->session);
1886
1887 /*
1888 * FIXME
1889 *
1890 * This function may returns 0 or 1 to indicate whether or not
1891 * there is data pending. In case of error, it should return an
1892 * LTTNG_ERR code. However, some code paths may still return
1893 * a nondescript error code, which we handle by returning an
1894 * "unknown" error.
1895 */
1896 if (pending_ret == 0 || pending_ret == 1) {
1897 /*
1898 * ret will be set to LTTNG_OK at the end of
1899 * this function.
1900 */
1901 } else if (pending_ret < 0) {
1902 ret = LTTNG_ERR_UNK;
1903 goto setup_error;
1904 } else {
1905 ret = pending_ret;
1906 goto setup_error;
1907 }
1908
1909 pending_ret_byte = (uint8_t) pending_ret;
1910
1911 /* 1 byte to return whether or not data is pending */
1912 ret = setup_lttng_msg_no_cmd_header(cmd_ctx,
1913 &pending_ret_byte, 1);
1914
1915 if (ret < 0) {
1916 goto setup_error;
1917 }
1918
1919 ret = LTTNG_OK;
1920 break;
1921 }
1922 case LTTNG_SNAPSHOT_ADD_OUTPUT:
1923 {
1924 uint32_t snapshot_id;
1925 struct lttcomm_lttng_output_id reply;
1926
1927 ret = cmd_snapshot_add_output(cmd_ctx->session,
1928 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.snapshot_output.output),
1929 &snapshot_id);
1930 if (ret != LTTNG_OK) {
1931 goto error;
1932 }
1933 reply.id = snapshot_id;
1934
1935 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &reply,
1936 sizeof(reply));
1937 if (ret < 0) {
1938 goto setup_error;
1939 }
1940
1941 /* Copy output list into message payload */
1942 ret = LTTNG_OK;
1943 break;
1944 }
1945 case LTTNG_SNAPSHOT_DEL_OUTPUT:
1946 {
1947 ret = cmd_snapshot_del_output(cmd_ctx->session,
1948 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.snapshot_output.output));
1949 break;
1950 }
1951 case LTTNG_SNAPSHOT_LIST_OUTPUT:
1952 {
1953 ssize_t nb_output;
1954 struct lttng_snapshot_output *outputs = NULL;
1955
1956 nb_output = cmd_snapshot_list_outputs(cmd_ctx->session, &outputs);
1957 if (nb_output < 0) {
1958 ret = -nb_output;
1959 goto error;
1960 }
1961
1962 assert((nb_output > 0 && outputs) || nb_output == 0);
1963 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, outputs,
1964 nb_output * sizeof(struct lttng_snapshot_output));
1965 free(outputs);
1966
1967 if (ret < 0) {
1968 goto setup_error;
1969 }
1970
1971 ret = LTTNG_OK;
1972 break;
1973 }
1974 case LTTNG_SNAPSHOT_RECORD:
1975 {
1976 ret = cmd_snapshot_record(cmd_ctx->session,
1977 ALIGNED_CONST_PTR(cmd_ctx->lsm.u.snapshot_record.output),
1978 cmd_ctx->lsm.u.snapshot_record.wait);
1979 break;
1980 }
1981 case LTTNG_CREATE_SESSION_EXT:
1982 {
1983 struct lttng_dynamic_buffer payload;
1984 struct lttng_session_descriptor *return_descriptor = NULL;
1985
1986 lttng_dynamic_buffer_init(&payload);
1987 ret = cmd_create_session(cmd_ctx, *sock, &return_descriptor);
1988 if (ret != LTTNG_OK) {
1989 goto error;
1990 }
1991
1992 ret = lttng_session_descriptor_serialize(return_descriptor,
1993 &payload);
1994 if (ret) {
1995 ERR("Failed to serialize session descriptor in reply to \"create session\" command");
1996 lttng_session_descriptor_destroy(return_descriptor);
1997 ret = LTTNG_ERR_NOMEM;
1998 goto error;
1999 }
2000 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, payload.data,
2001 payload.size);
2002 if (ret) {
2003 lttng_session_descriptor_destroy(return_descriptor);
2004 ret = LTTNG_ERR_NOMEM;
2005 goto error;
2006 }
2007 lttng_dynamic_buffer_reset(&payload);
2008 lttng_session_descriptor_destroy(return_descriptor);
2009 ret = LTTNG_OK;
2010 break;
2011 }
2012 case LTTNG_SAVE_SESSION:
2013 {
2014 ret = cmd_save_sessions(&cmd_ctx->lsm.u.save_session.attr,
2015 &cmd_ctx->creds);
2016 break;
2017 }
2018 case LTTNG_SET_SESSION_SHM_PATH:
2019 {
2020 ret = cmd_set_session_shm_path(cmd_ctx->session,
2021 cmd_ctx->lsm.u.set_shm_path.shm_path);
2022 break;
2023 }
2024 case LTTNG_REGENERATE_METADATA:
2025 {
2026 ret = cmd_regenerate_metadata(cmd_ctx->session);
2027 break;
2028 }
2029 case LTTNG_REGENERATE_STATEDUMP:
2030 {
2031 ret = cmd_regenerate_statedump(cmd_ctx->session);
2032 break;
2033 }
2034 case LTTNG_REGISTER_TRIGGER:
2035 {
2036 ret = cmd_register_trigger(cmd_ctx, *sock,
2037 notification_thread_handle);
2038 break;
2039 }
2040 case LTTNG_UNREGISTER_TRIGGER:
2041 {
2042 ret = cmd_unregister_trigger(cmd_ctx, *sock,
2043 notification_thread_handle);
2044 break;
2045 }
2046 case LTTNG_ROTATE_SESSION:
2047 {
2048 struct lttng_rotate_session_return rotate_return;
2049
2050 DBG("Client rotate session \"%s\"", cmd_ctx->session->name);
2051
2052 memset(&rotate_return, 0, sizeof(rotate_return));
2053 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
2054 DBG("Kernel tracer version is not compatible with the rotation feature");
2055 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
2056 goto error;
2057 }
2058
2059 ret = cmd_rotate_session(cmd_ctx->session, &rotate_return,
2060 false,
2061 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
2062 if (ret < 0) {
2063 ret = -ret;
2064 goto error;
2065 }
2066
2067 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &rotate_return,
2068 sizeof(rotate_return));
2069 if (ret < 0) {
2070 ret = -ret;
2071 goto error;
2072 }
2073
2074 ret = LTTNG_OK;
2075 break;
2076 }
2077 case LTTNG_ROTATION_GET_INFO:
2078 {
2079 struct lttng_rotation_get_info_return get_info_return;
2080
2081 memset(&get_info_return, 0, sizeof(get_info_return));
2082 ret = cmd_rotate_get_info(cmd_ctx->session, &get_info_return,
2083 cmd_ctx->lsm.u.get_rotation_info.rotation_id);
2084 if (ret < 0) {
2085 ret = -ret;
2086 goto error;
2087 }
2088
2089 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &get_info_return,
2090 sizeof(get_info_return));
2091 if (ret < 0) {
2092 ret = -ret;
2093 goto error;
2094 }
2095
2096 ret = LTTNG_OK;
2097 break;
2098 }
2099 case LTTNG_ROTATION_SET_SCHEDULE:
2100 {
2101 bool set_schedule;
2102 enum lttng_rotation_schedule_type schedule_type;
2103 uint64_t value;
2104
2105 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
2106 DBG("Kernel tracer version does not support session rotations");
2107 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
2108 goto error;
2109 }
2110
2111 set_schedule = cmd_ctx->lsm.u.rotation_set_schedule.set == 1;
2112 schedule_type = (enum lttng_rotation_schedule_type) cmd_ctx->lsm.u.rotation_set_schedule.type;
2113 value = cmd_ctx->lsm.u.rotation_set_schedule.value;
2114
2115 ret = cmd_rotation_set_schedule(cmd_ctx->session,
2116 set_schedule,
2117 schedule_type,
2118 value,
2119 notification_thread_handle);
2120 if (ret != LTTNG_OK) {
2121 goto error;
2122 }
2123
2124 break;
2125 }
2126 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
2127 {
2128 struct lttng_session_list_schedules_return schedules = {
2129 .periodic.set = !!cmd_ctx->session->rotate_timer_period,
2130 .periodic.value = cmd_ctx->session->rotate_timer_period,
2131 .size.set = !!cmd_ctx->session->rotate_size,
2132 .size.value = cmd_ctx->session->rotate_size,
2133 };
2134
2135 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &schedules,
2136 sizeof(schedules));
2137 if (ret < 0) {
2138 ret = -ret;
2139 goto error;
2140 }
2141
2142 ret = LTTNG_OK;
2143 break;
2144 }
2145 case LTTNG_CLEAR_SESSION:
2146 {
2147 ret = cmd_clear_session(cmd_ctx->session, sock);
2148 break;
2149 }
2150 default:
2151 ret = LTTNG_ERR_UND;
2152 break;
2153 }
2154
2155 error:
2156 if (cmd_ctx->reply_payload.buffer.size == 0) {
2157 DBG("Missing llm header, creating one.");
2158 if (setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0) < 0) {
2159 goto setup_error;
2160 }
2161 }
2162 /* Set return code */
2163 ((struct lttcomm_lttng_msg *) (cmd_ctx->reply_payload.buffer.data))->ret_code = ret;
2164 setup_error:
2165 if (cmd_ctx->session) {
2166 session_unlock(cmd_ctx->session);
2167 session_put(cmd_ctx->session);
2168 cmd_ctx->session = NULL;
2169 }
2170 if (need_tracing_session) {
2171 session_unlock_list();
2172 }
2173 init_setup_error:
2174 assert(!rcu_read_ongoing());
2175 return ret;
2176 }
2177
2178 static int create_client_sock(void)
2179 {
2180 int ret, client_sock;
2181 const mode_t old_umask = umask(0);
2182
2183 /* Create client tool unix socket */
2184 client_sock = lttcomm_create_unix_sock(config.client_unix_sock_path.value);
2185 if (client_sock < 0) {
2186 ERR("Create unix sock failed: %s", config.client_unix_sock_path.value);
2187 ret = -1;
2188 goto end;
2189 }
2190
2191 /* Set the cloexec flag */
2192 ret = utils_set_fd_cloexec(client_sock);
2193 if (ret < 0) {
2194 ERR("Unable to set CLOEXEC flag to the client Unix socket (fd: %d). "
2195 "Continuing but note that the consumer daemon will have a "
2196 "reference to this socket on exec()", client_sock);
2197 }
2198
2199 /* File permission MUST be 660 */
2200 ret = chmod(config.client_unix_sock_path.value, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
2201 if (ret < 0) {
2202 ERR("Set file permissions failed: %s",
2203 config.client_unix_sock_path.value);
2204 PERROR("chmod");
2205 (void) lttcomm_close_unix_sock(client_sock);
2206 ret = -1;
2207 goto end;
2208 }
2209 DBG("Created client socket (fd = %i)", client_sock);
2210 ret = client_sock;
2211 end:
2212 umask(old_umask);
2213 return ret;
2214 }
2215
2216 static void cleanup_client_thread(void *data)
2217 {
2218 struct lttng_pipe *quit_pipe = data;
2219
2220 lttng_pipe_destroy(quit_pipe);
2221 }
2222
2223 static void thread_init_cleanup(void *data)
2224 {
2225 set_thread_status(false);
2226 }
2227
2228 /*
2229 * This thread manage all clients request using the unix client socket for
2230 * communication.
2231 */
2232 static void *thread_manage_clients(void *data)
2233 {
2234 int sock = -1, ret, i, pollfd, err = -1;
2235 int sock_error;
2236 uint32_t revents, nb_fd;
2237 struct lttng_poll_event events;
2238 const int client_sock = thread_state.client_sock;
2239 struct lttng_pipe *quit_pipe = data;
2240 const int thread_quit_pipe_fd = lttng_pipe_get_readfd(quit_pipe);
2241 struct command_ctx cmd_ctx = {};
2242
2243 DBG("[thread] Manage client started");
2244
2245 lttng_payload_init(&cmd_ctx.reply_payload);
2246
2247 is_root = (getuid() == 0);
2248
2249 pthread_cleanup_push(thread_init_cleanup, NULL);
2250
2251 rcu_register_thread();
2252
2253 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_CMD);
2254
2255 health_code_update();
2256
2257 ret = lttcomm_listen_unix_sock(client_sock);
2258 if (ret < 0) {
2259 goto error_listen;
2260 }
2261
2262 /*
2263 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2264 * more will be added to this poll set.
2265 */
2266 ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
2267 if (ret < 0) {
2268 goto error_create_poll;
2269 }
2270
2271 /* Add the application registration socket */
2272 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
2273 if (ret < 0) {
2274 goto error;
2275 }
2276
2277 /* Add thread quit pipe */
2278 ret = lttng_poll_add(&events, thread_quit_pipe_fd, LPOLLIN | LPOLLERR);
2279 if (ret < 0) {
2280 goto error;
2281 }
2282
2283 /* Set state as running. */
2284 set_thread_status(true);
2285 pthread_cleanup_pop(0);
2286
2287 /* This testpoint is after we signal readiness to the parent. */
2288 if (testpoint(sessiond_thread_manage_clients)) {
2289 goto error;
2290 }
2291
2292 if (testpoint(sessiond_thread_manage_clients_before_loop)) {
2293 goto error;
2294 }
2295
2296 health_code_update();
2297
2298 while (1) {
2299 const struct cmd_completion_handler *cmd_completion_handler;
2300
2301 cmd_ctx.creds = (lttng_sock_cred) {
2302 .uid = UINT32_MAX,
2303 .gid = UINT32_MAX,
2304 };
2305 cmd_ctx.session = NULL;
2306 lttng_payload_clear(&cmd_ctx.reply_payload);
2307 cmd_ctx.lttng_msg_size = 0;
2308
2309 DBG("Accepting client command ...");
2310
2311 /* Inifinite blocking call, waiting for transmission */
2312 restart:
2313 health_poll_entry();
2314 ret = lttng_poll_wait(&events, -1);
2315 health_poll_exit();
2316 if (ret < 0) {
2317 /*
2318 * Restart interrupted system call.
2319 */
2320 if (errno == EINTR) {
2321 goto restart;
2322 }
2323 goto error;
2324 }
2325
2326 nb_fd = ret;
2327
2328 for (i = 0; i < nb_fd; i++) {
2329 revents = LTTNG_POLL_GETEV(&events, i);
2330 pollfd = LTTNG_POLL_GETFD(&events, i);
2331
2332 health_code_update();
2333
2334 if (pollfd == thread_quit_pipe_fd) {
2335 err = 0;
2336 goto exit;
2337 } else {
2338 /* Event on the registration socket */
2339 if (revents & LPOLLIN) {
2340 continue;
2341 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2342 ERR("Client socket poll error");
2343 goto error;
2344 } else {
2345 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
2346 goto error;
2347 }
2348 }
2349 }
2350
2351 DBG("Wait for client response");
2352
2353 health_code_update();
2354
2355 sock = lttcomm_accept_unix_sock(client_sock);
2356 if (sock < 0) {
2357 goto error;
2358 }
2359
2360 /*
2361 * Set the CLOEXEC flag. Return code is useless because either way, the
2362 * show must go on.
2363 */
2364 (void) utils_set_fd_cloexec(sock);
2365
2366 /* Set socket option for credentials retrieval */
2367 ret = lttcomm_setsockopt_creds_unix_sock(sock);
2368 if (ret < 0) {
2369 goto error;
2370 }
2371
2372 health_code_update();
2373
2374 /*
2375 * Data is received from the lttng client. The struct
2376 * lttcomm_session_msg (lsm) contains the command and data request of
2377 * the client.
2378 */
2379 DBG("Receiving data from client ...");
2380 ret = lttcomm_recv_creds_unix_sock(sock, &cmd_ctx.lsm,
2381 sizeof(struct lttcomm_session_msg), &cmd_ctx.creds);
2382 if (ret != sizeof(struct lttcomm_session_msg)) {
2383 DBG("Incomplete recv() from client... continuing");
2384 ret = close(sock);
2385 if (ret) {
2386 PERROR("close");
2387 }
2388 sock = -1;
2389 continue;
2390 }
2391
2392 health_code_update();
2393
2394 // TODO: Validate cmd_ctx including sanity check for
2395 // security purpose.
2396
2397 rcu_thread_online();
2398 /*
2399 * This function dispatch the work to the kernel or userspace tracer
2400 * libs and fill the lttcomm_lttng_msg data structure of all the needed
2401 * informations for the client. The command context struct contains
2402 * everything this function may needs.
2403 */
2404 ret = process_client_msg(&cmd_ctx, &sock, &sock_error);
2405 rcu_thread_offline();
2406 if (ret < 0) {
2407 if (sock >= 0) {
2408 ret = close(sock);
2409 if (ret) {
2410 PERROR("close");
2411 }
2412 }
2413 sock = -1;
2414 /*
2415 * TODO: Inform client somehow of the fatal error. At
2416 * this point, ret < 0 means that a zmalloc failed
2417 * (ENOMEM). Error detected but still accept
2418 * command, unless a socket error has been
2419 * detected.
2420 */
2421 continue;
2422 }
2423
2424 cmd_completion_handler = cmd_pop_completion_handler();
2425 if (cmd_completion_handler) {
2426 enum lttng_error_code completion_code;
2427
2428 completion_code = cmd_completion_handler->run(
2429 cmd_completion_handler->data);
2430 if (completion_code != LTTNG_OK) {
2431 continue;
2432 }
2433 }
2434
2435 health_code_update();
2436
2437 if (sock >= 0) {
2438 struct lttng_payload_view view =
2439 lttng_payload_view_from_payload(
2440 &cmd_ctx.reply_payload,
2441 0, -1);
2442 struct lttcomm_lttng_msg *llm = (typeof(
2443 llm)) cmd_ctx.reply_payload.buffer.data;
2444
2445 assert(cmd_ctx.reply_payload.buffer.size >=
2446 sizeof(llm));
2447 assert(cmd_ctx.lttng_msg_size == cmd_ctx.reply_payload.buffer.size);
2448
2449 llm->fd_count = lttng_payload_view_get_fd_handle_count(&view);
2450
2451 DBG("Sending response (size: %d, retcode: %s (%d))",
2452 cmd_ctx.lttng_msg_size,
2453 lttng_strerror(-llm->ret_code),
2454 llm->ret_code);
2455 ret = send_unix_sock(sock, &view);
2456 if (ret < 0) {
2457 ERR("Failed to send data back to client");
2458 }
2459
2460 /* End of transmission */
2461 ret = close(sock);
2462 if (ret) {
2463 PERROR("close");
2464 }
2465 }
2466 sock = -1;
2467
2468 health_code_update();
2469 }
2470
2471 exit:
2472 error:
2473 if (sock >= 0) {
2474 ret = close(sock);
2475 if (ret) {
2476 PERROR("close");
2477 }
2478 }
2479
2480 lttng_poll_clean(&events);
2481
2482 error_listen:
2483 error_create_poll:
2484 unlink(config.client_unix_sock_path.value);
2485 ret = close(client_sock);
2486 if (ret) {
2487 PERROR("close");
2488 }
2489
2490 if (err) {
2491 health_error();
2492 ERR("Health error occurred in %s", __func__);
2493 }
2494
2495 health_unregister(health_sessiond);
2496
2497 DBG("Client thread dying");
2498 lttng_payload_reset(&cmd_ctx.reply_payload);
2499 rcu_unregister_thread();
2500 return NULL;
2501 }
2502
2503 static
2504 bool shutdown_client_thread(void *thread_data)
2505 {
2506 struct lttng_pipe *client_quit_pipe = thread_data;
2507 const int write_fd = lttng_pipe_get_writefd(client_quit_pipe);
2508
2509 return notify_thread_pipe(write_fd) == 1;
2510 }
2511
2512 struct lttng_thread *launch_client_thread(void)
2513 {
2514 bool thread_running;
2515 struct lttng_pipe *client_quit_pipe;
2516 struct lttng_thread *thread = NULL;
2517 int client_sock_fd = -1;
2518
2519 sem_init(&thread_state.ready, 0, 0);
2520 client_quit_pipe = lttng_pipe_open(FD_CLOEXEC);
2521 if (!client_quit_pipe) {
2522 goto error;
2523 }
2524
2525 client_sock_fd = create_client_sock();
2526 if (client_sock_fd < 0) {
2527 goto error;
2528 }
2529
2530 thread_state.client_sock = client_sock_fd;
2531 thread = lttng_thread_create("Client management",
2532 thread_manage_clients,
2533 shutdown_client_thread,
2534 cleanup_client_thread,
2535 client_quit_pipe);
2536 if (!thread) {
2537 goto error;
2538 }
2539 /* The client thread now owns the client sock fd and the quit pipe. */
2540 client_sock_fd = -1;
2541 client_quit_pipe = NULL;
2542
2543 /*
2544 * This thread is part of the threads that need to be fully
2545 * initialized before the session daemon is marked as "ready".
2546 */
2547 thread_running = wait_thread_status();
2548 if (!thread_running) {
2549 goto error;
2550 }
2551 return thread;
2552 error:
2553 if (client_sock_fd >= 0) {
2554 if (close(client_sock_fd)) {
2555 PERROR("Failed to close client socket");
2556 }
2557 }
2558 lttng_thread_put(thread);
2559 cleanup_client_thread(client_quit_pipe);
2560 return NULL;
2561 }
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