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Fix: liblttng-ctl comm: lttng_channel is not packed
[lttng-tools.git] / src / bin / lttng-sessiond / client.c
1 /*
2 * Copyright (C) 2011 EfficiOS Inc.
3 * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 * Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com>
5 *
6 * SPDX-License-Identifier: GPL-2.0-only
7 *
8 */
9
10 #include "common/buffer-view.h"
11 #include "common/dynamic-buffer.h"
12 #include "common/sessiond-comm/sessiond-comm.h"
13 #include "lttng/lttng-error.h"
14 #include "lttng/tracker.h"
15 #include <common/compat/getenv.h>
16 #include <common/tracker.h>
17 #include <common/unix.h>
18 #include <common/utils.h>
19 #include <lttng/event-internal.h>
20 #include <lttng/session-descriptor-internal.h>
21 #include <lttng/session-internal.h>
22 #include <lttng/userspace-probe-internal.h>
23 #include <pthread.h>
24 #include <signal.h>
25 #include <stddef.h>
26 #include <stdint.h>
27 #include <sys/stat.h>
28
29 #include "client.h"
30 #include "lttng-sessiond.h"
31 #include "cmd.h"
32 #include "kernel.h"
33 #include "save.h"
34 #include "health-sessiond.h"
35 #include "testpoint.h"
36 #include "utils.h"
37 #include "manage-consumer.h"
38 #include "clear.h"
39
40 static bool is_root;
41
42 static struct thread_state {
43 sem_t ready;
44 bool running;
45 int client_sock;
46 } thread_state;
47
48 static void set_thread_status(bool running)
49 {
50 DBG("Marking client thread's state as %s", running ? "running" : "error");
51 thread_state.running = running;
52 sem_post(&thread_state.ready);
53 }
54
55 static bool wait_thread_status(void)
56 {
57 DBG("Waiting for client thread to be ready");
58 sem_wait(&thread_state.ready);
59 if (thread_state.running) {
60 DBG("Client thread is ready");
61 } else {
62 ERR("Initialization of client thread failed");
63 }
64
65 return thread_state.running;
66 }
67
68 /*
69 * Setup the outgoing data buffer for the response (llm) by allocating the
70 * right amount of memory and copying the original information from the lsm
71 * structure.
72 *
73 * Return 0 on success, negative value on error.
74 */
75 static int setup_lttng_msg(struct command_ctx *cmd_ctx,
76 const void *payload_buf, size_t payload_len,
77 const void *cmd_header_buf, size_t cmd_header_len)
78 {
79 int ret = 0;
80 const size_t header_len = sizeof(struct lttcomm_lttng_msg);
81 const size_t cmd_header_offset = header_len;
82 const size_t payload_offset = cmd_header_offset + cmd_header_len;
83 const size_t total_msg_size = header_len + cmd_header_len + payload_len;
84
85 free(cmd_ctx->llm);
86 cmd_ctx->llm = zmalloc(total_msg_size);
87
88 if (cmd_ctx->llm == NULL) {
89 PERROR("zmalloc");
90 ret = -ENOMEM;
91 goto end;
92 }
93
94 /* Copy common data */
95 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
96 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
97 cmd_ctx->llm->cmd_header_size = cmd_header_len;
98 cmd_ctx->llm->data_size = payload_len;
99 cmd_ctx->lttng_msg_size = total_msg_size;
100
101 /* Copy command header */
102 if (cmd_header_len) {
103 memcpy(((uint8_t *) cmd_ctx->llm) + cmd_header_offset, cmd_header_buf,
104 cmd_header_len);
105 }
106
107 /* Copy payload */
108 if (payload_len) {
109 memcpy(((uint8_t *) cmd_ctx->llm) + payload_offset, payload_buf,
110 payload_len);
111 }
112
113 end:
114 return ret;
115 }
116
117 /*
118 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
119 * exec or it will fail.
120 */
121 static int spawn_consumer_thread(struct consumer_data *consumer_data)
122 {
123 return launch_consumer_management_thread(consumer_data) ? 0 : -1;
124 }
125
126 /*
127 * Fork and exec a consumer daemon (consumerd).
128 *
129 * Return pid if successful else -1.
130 */
131 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
132 {
133 int ret;
134 pid_t pid;
135 const char *consumer_to_use;
136 const char *verbosity;
137 struct stat st;
138
139 DBG("Spawning consumerd");
140
141 pid = fork();
142 if (pid == 0) {
143 /*
144 * Exec consumerd.
145 */
146 if (config.verbose_consumer) {
147 verbosity = "--verbose";
148 } else if (lttng_opt_quiet) {
149 verbosity = "--quiet";
150 } else {
151 verbosity = "";
152 }
153
154 switch (consumer_data->type) {
155 case LTTNG_CONSUMER_KERNEL:
156 /*
157 * Find out which consumerd to execute. We will first try the
158 * 64-bit path, then the sessiond's installation directory, and
159 * fallback on the 32-bit one,
160 */
161 DBG3("Looking for a kernel consumer at these locations:");
162 DBG3(" 1) %s", config.consumerd64_bin_path.value ? : "NULL");
163 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, DEFAULT_CONSUMERD_FILE);
164 DBG3(" 3) %s", config.consumerd32_bin_path.value ? : "NULL");
165 if (stat(config.consumerd64_bin_path.value, &st) == 0) {
166 DBG3("Found location #1");
167 consumer_to_use = config.consumerd64_bin_path.value;
168 } else if (stat(INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE, &st) == 0) {
169 DBG3("Found location #2");
170 consumer_to_use = INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE;
171 } else if (config.consumerd32_bin_path.value &&
172 stat(config.consumerd32_bin_path.value, &st) == 0) {
173 DBG3("Found location #3");
174 consumer_to_use = config.consumerd32_bin_path.value;
175 } else {
176 DBG("Could not find any valid consumerd executable");
177 ret = -EINVAL;
178 goto error;
179 }
180 DBG("Using kernel consumer at: %s", consumer_to_use);
181 (void) execl(consumer_to_use,
182 "lttng-consumerd", verbosity, "-k",
183 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
184 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
185 "--group", config.tracing_group_name.value,
186 NULL);
187 break;
188 case LTTNG_CONSUMER64_UST:
189 {
190 if (config.consumerd64_lib_dir.value) {
191 const char *tmp;
192 size_t tmplen;
193 char *tmpnew;
194
195 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
196 if (!tmp) {
197 tmp = "";
198 }
199 tmplen = strlen(config.consumerd64_lib_dir.value) + 1 /* : */ + strlen(tmp);
200 tmpnew = zmalloc(tmplen + 1 /* \0 */);
201 if (!tmpnew) {
202 ret = -ENOMEM;
203 goto error;
204 }
205 strcat(tmpnew, config.consumerd64_lib_dir.value);
206 if (tmp[0] != '\0') {
207 strcat(tmpnew, ":");
208 strcat(tmpnew, tmp);
209 }
210 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
211 free(tmpnew);
212 if (ret) {
213 ret = -errno;
214 goto error;
215 }
216 }
217 DBG("Using 64-bit UST consumer at: %s", config.consumerd64_bin_path.value);
218 (void) execl(config.consumerd64_bin_path.value, "lttng-consumerd", verbosity, "-u",
219 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
220 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
221 "--group", config.tracing_group_name.value,
222 NULL);
223 break;
224 }
225 case LTTNG_CONSUMER32_UST:
226 {
227 if (config.consumerd32_lib_dir.value) {
228 const char *tmp;
229 size_t tmplen;
230 char *tmpnew;
231
232 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
233 if (!tmp) {
234 tmp = "";
235 }
236 tmplen = strlen(config.consumerd32_lib_dir.value) + 1 /* : */ + strlen(tmp);
237 tmpnew = zmalloc(tmplen + 1 /* \0 */);
238 if (!tmpnew) {
239 ret = -ENOMEM;
240 goto error;
241 }
242 strcat(tmpnew, config.consumerd32_lib_dir.value);
243 if (tmp[0] != '\0') {
244 strcat(tmpnew, ":");
245 strcat(tmpnew, tmp);
246 }
247 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
248 free(tmpnew);
249 if (ret) {
250 ret = -errno;
251 goto error;
252 }
253 }
254 DBG("Using 32-bit UST consumer at: %s", config.consumerd32_bin_path.value);
255 (void) execl(config.consumerd32_bin_path.value, "lttng-consumerd", verbosity, "-u",
256 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
257 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
258 "--group", config.tracing_group_name.value,
259 NULL);
260 break;
261 }
262 default:
263 ERR("unknown consumer type");
264 errno = 0;
265 }
266 if (errno != 0) {
267 PERROR("Consumer execl()");
268 }
269 /* Reaching this point, we got a failure on our execl(). */
270 exit(EXIT_FAILURE);
271 } else if (pid > 0) {
272 ret = pid;
273 } else {
274 PERROR("start consumer fork");
275 ret = -errno;
276 }
277 error:
278 return ret;
279 }
280
281 /*
282 * Spawn the consumerd daemon and session daemon thread.
283 */
284 static int start_consumerd(struct consumer_data *consumer_data)
285 {
286 int ret;
287
288 /*
289 * Set the listen() state on the socket since there is a possible race
290 * between the exec() of the consumer daemon and this call if place in the
291 * consumer thread. See bug #366 for more details.
292 */
293 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
294 if (ret < 0) {
295 goto error;
296 }
297
298 pthread_mutex_lock(&consumer_data->pid_mutex);
299 if (consumer_data->pid != 0) {
300 pthread_mutex_unlock(&consumer_data->pid_mutex);
301 goto end;
302 }
303
304 ret = spawn_consumerd(consumer_data);
305 if (ret < 0) {
306 ERR("Spawning consumerd failed");
307 pthread_mutex_unlock(&consumer_data->pid_mutex);
308 goto error;
309 }
310
311 /* Setting up the consumer_data pid */
312 consumer_data->pid = ret;
313 DBG2("Consumer pid %d", consumer_data->pid);
314 pthread_mutex_unlock(&consumer_data->pid_mutex);
315
316 DBG2("Spawning consumer control thread");
317 ret = spawn_consumer_thread(consumer_data);
318 if (ret < 0) {
319 ERR("Fatal error spawning consumer control thread");
320 goto error;
321 }
322
323 end:
324 return 0;
325
326 error:
327 /* Cleanup already created sockets on error. */
328 if (consumer_data->err_sock >= 0) {
329 int err;
330
331 err = close(consumer_data->err_sock);
332 if (err < 0) {
333 PERROR("close consumer data error socket");
334 }
335 }
336 return ret;
337 }
338
339 /*
340 * Copy consumer output from the tracing session to the domain session. The
341 * function also applies the right modification on a per domain basis for the
342 * trace files destination directory.
343 *
344 * Should *NOT* be called with RCU read-side lock held.
345 */
346 static int copy_session_consumer(int domain, struct ltt_session *session)
347 {
348 int ret;
349 const char *dir_name;
350 struct consumer_output *consumer;
351
352 assert(session);
353 assert(session->consumer);
354
355 switch (domain) {
356 case LTTNG_DOMAIN_KERNEL:
357 DBG3("Copying tracing session consumer output in kernel session");
358 /*
359 * XXX: We should audit the session creation and what this function
360 * does "extra" in order to avoid a destroy since this function is used
361 * in the domain session creation (kernel and ust) only. Same for UST
362 * domain.
363 */
364 if (session->kernel_session->consumer) {
365 consumer_output_put(session->kernel_session->consumer);
366 }
367 session->kernel_session->consumer =
368 consumer_copy_output(session->consumer);
369 /* Ease our life a bit for the next part */
370 consumer = session->kernel_session->consumer;
371 dir_name = DEFAULT_KERNEL_TRACE_DIR;
372 break;
373 case LTTNG_DOMAIN_JUL:
374 case LTTNG_DOMAIN_LOG4J:
375 case LTTNG_DOMAIN_PYTHON:
376 case LTTNG_DOMAIN_UST:
377 DBG3("Copying tracing session consumer output in UST session");
378 if (session->ust_session->consumer) {
379 consumer_output_put(session->ust_session->consumer);
380 }
381 session->ust_session->consumer =
382 consumer_copy_output(session->consumer);
383 /* Ease our life a bit for the next part */
384 consumer = session->ust_session->consumer;
385 dir_name = DEFAULT_UST_TRACE_DIR;
386 break;
387 default:
388 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
389 goto error;
390 }
391
392 /* Append correct directory to subdir */
393 ret = lttng_strncpy(consumer->domain_subdir, dir_name,
394 sizeof(consumer->domain_subdir));
395 if (ret) {
396 ret = LTTNG_ERR_UNK;
397 goto error;
398 }
399 DBG3("Copy session consumer subdir %s", consumer->domain_subdir);
400 ret = LTTNG_OK;
401
402 error:
403 return ret;
404 }
405
406 /*
407 * Create an UST session and add it to the session ust list.
408 *
409 * Should *NOT* be called with RCU read-side lock held.
410 */
411 static int create_ust_session(struct ltt_session *session,
412 const struct lttng_domain *domain)
413 {
414 int ret;
415 struct ltt_ust_session *lus = NULL;
416
417 assert(session);
418 assert(domain);
419 assert(session->consumer);
420
421 switch (domain->type) {
422 case LTTNG_DOMAIN_JUL:
423 case LTTNG_DOMAIN_LOG4J:
424 case LTTNG_DOMAIN_PYTHON:
425 case LTTNG_DOMAIN_UST:
426 break;
427 default:
428 ERR("Unknown UST domain on create session %d", domain->type);
429 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
430 goto error;
431 }
432
433 DBG("Creating UST session");
434
435 lus = trace_ust_create_session(session->id);
436 if (lus == NULL) {
437 ret = LTTNG_ERR_UST_SESS_FAIL;
438 goto error;
439 }
440
441 lus->uid = session->uid;
442 lus->gid = session->gid;
443 lus->output_traces = session->output_traces;
444 lus->snapshot_mode = session->snapshot_mode;
445 lus->live_timer_interval = session->live_timer;
446 session->ust_session = lus;
447 if (session->shm_path[0]) {
448 strncpy(lus->root_shm_path, session->shm_path,
449 sizeof(lus->root_shm_path));
450 lus->root_shm_path[sizeof(lus->root_shm_path) - 1] = '\0';
451 strncpy(lus->shm_path, session->shm_path,
452 sizeof(lus->shm_path));
453 lus->shm_path[sizeof(lus->shm_path) - 1] = '\0';
454 strncat(lus->shm_path, "/ust",
455 sizeof(lus->shm_path) - strlen(lus->shm_path) - 1);
456 }
457 /* Copy session output to the newly created UST session */
458 ret = copy_session_consumer(domain->type, session);
459 if (ret != LTTNG_OK) {
460 goto error;
461 }
462
463 return LTTNG_OK;
464
465 error:
466 free(lus);
467 session->ust_session = NULL;
468 return ret;
469 }
470
471 /*
472 * Create a kernel tracer session then create the default channel.
473 */
474 static int create_kernel_session(struct ltt_session *session)
475 {
476 int ret;
477
478 DBG("Creating kernel session");
479
480 ret = kernel_create_session(session);
481 if (ret < 0) {
482 ret = LTTNG_ERR_KERN_SESS_FAIL;
483 goto error_create;
484 }
485
486 /* Code flow safety */
487 assert(session->kernel_session);
488
489 /* Copy session output to the newly created Kernel session */
490 ret = copy_session_consumer(LTTNG_DOMAIN_KERNEL, session);
491 if (ret != LTTNG_OK) {
492 goto error;
493 }
494
495 session->kernel_session->uid = session->uid;
496 session->kernel_session->gid = session->gid;
497 session->kernel_session->output_traces = session->output_traces;
498 session->kernel_session->snapshot_mode = session->snapshot_mode;
499 session->kernel_session->is_live_session = session->live_timer != 0;
500
501 return LTTNG_OK;
502
503 error:
504 trace_kernel_destroy_session(session->kernel_session);
505 session->kernel_session = NULL;
506 error_create:
507 return ret;
508 }
509
510 /*
511 * Count number of session permitted by uid/gid.
512 */
513 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
514 {
515 unsigned int i = 0;
516 struct ltt_session *session;
517 const struct ltt_session_list *session_list = session_get_list();
518
519 DBG("Counting number of available session for UID %d GID %d",
520 uid, gid);
521 cds_list_for_each_entry(session, &session_list->head, list) {
522 if (!session_get(session)) {
523 continue;
524 }
525 session_lock(session);
526 /* Only count the sessions the user can control. */
527 if (session_access_ok(session, uid, gid) &&
528 !session->destroyed) {
529 i++;
530 }
531 session_unlock(session);
532 session_put(session);
533 }
534 return i;
535 }
536
537 static int receive_userspace_probe(struct command_ctx *cmd_ctx, int sock,
538 int *sock_error, struct lttng_event *event)
539 {
540 int fd, ret;
541 struct lttng_userspace_probe_location *probe_location;
542 const struct lttng_userspace_probe_location_lookup_method *lookup = NULL;
543 struct lttng_dynamic_buffer probe_location_buffer;
544 struct lttng_buffer_view buffer_view;
545
546 /*
547 * Create a buffer to store the serialized version of the probe
548 * location.
549 */
550 lttng_dynamic_buffer_init(&probe_location_buffer);
551 ret = lttng_dynamic_buffer_set_size(&probe_location_buffer,
552 cmd_ctx->lsm->u.enable.userspace_probe_location_len);
553 if (ret) {
554 ret = LTTNG_ERR_NOMEM;
555 goto error;
556 }
557
558 /*
559 * Receive the probe location.
560 */
561 ret = lttcomm_recv_unix_sock(sock, probe_location_buffer.data,
562 probe_location_buffer.size);
563 if (ret <= 0) {
564 DBG("Nothing recv() from client var len data... continuing");
565 *sock_error = 1;
566 lttng_dynamic_buffer_reset(&probe_location_buffer);
567 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
568 goto error;
569 }
570
571 buffer_view = lttng_buffer_view_from_dynamic_buffer(
572 &probe_location_buffer, 0, probe_location_buffer.size);
573
574 /*
575 * Extract the probe location from the serialized version.
576 */
577 ret = lttng_userspace_probe_location_create_from_buffer(
578 &buffer_view, &probe_location);
579 if (ret < 0) {
580 WARN("Failed to create a userspace probe location from the received buffer");
581 lttng_dynamic_buffer_reset( &probe_location_buffer);
582 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
583 goto error;
584 }
585
586 /*
587 * Receive the file descriptor to the target binary from the client.
588 */
589 DBG("Receiving userspace probe target FD from client ...");
590 ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1);
591 if (ret <= 0) {
592 DBG("Nothing recv() from client userspace probe fd... continuing");
593 *sock_error = 1;
594 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
595 goto error;
596 }
597
598 /*
599 * Set the file descriptor received from the client through the unix
600 * socket in the probe location.
601 */
602 lookup = lttng_userspace_probe_location_get_lookup_method(probe_location);
603 if (!lookup) {
604 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
605 goto error;
606 }
607
608 /*
609 * From the kernel tracer's perspective, all userspace probe event types
610 * are all the same: a file and an offset.
611 */
612 switch (lttng_userspace_probe_location_lookup_method_get_type(lookup)) {
613 case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF:
614 ret = lttng_userspace_probe_location_function_set_binary_fd(
615 probe_location, fd);
616 break;
617 case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT:
618 ret = lttng_userspace_probe_location_tracepoint_set_binary_fd(
619 probe_location, fd);
620 break;
621 default:
622 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
623 goto error;
624 }
625
626 if (ret) {
627 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
628 goto error;
629 }
630
631 /* Attach the probe location to the event. */
632 ret = lttng_event_set_userspace_probe_location(event, probe_location);
633 if (ret) {
634 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
635 goto error;
636 }
637
638 lttng_dynamic_buffer_reset(&probe_location_buffer);
639 error:
640 return ret;
641 }
642
643 /*
644 * Version of setup_lttng_msg() without command header.
645 */
646 static int setup_lttng_msg_no_cmd_header(struct command_ctx *cmd_ctx,
647 void *payload_buf, size_t payload_len)
648 {
649 return setup_lttng_msg(cmd_ctx, payload_buf, payload_len, NULL, 0);
650 }
651
652 /*
653 * Free memory of a command context structure.
654 */
655 static void clean_command_ctx(struct command_ctx **cmd_ctx)
656 {
657 DBG("Clean command context structure");
658 if (*cmd_ctx) {
659 if ((*cmd_ctx)->llm) {
660 free((*cmd_ctx)->llm);
661 }
662 if ((*cmd_ctx)->lsm) {
663 free((*cmd_ctx)->lsm);
664 }
665 free(*cmd_ctx);
666 *cmd_ctx = NULL;
667 }
668 }
669
670 /*
671 * Check if the current kernel tracer supports the session rotation feature.
672 * Return 1 if it does, 0 otherwise.
673 */
674 static int check_rotate_compatible(void)
675 {
676 int ret = 1;
677
678 if (kernel_tracer_version.major != 2 || kernel_tracer_version.minor < 11) {
679 DBG("Kernel tracer version is not compatible with the rotation feature");
680 ret = 0;
681 }
682
683 return ret;
684 }
685
686 /*
687 * Send data on a unix socket using the liblttsessiondcomm API.
688 *
689 * Return lttcomm error code.
690 */
691 static int send_unix_sock(int sock, void *buf, size_t len)
692 {
693 /* Check valid length */
694 if (len == 0) {
695 return -1;
696 }
697
698 return lttcomm_send_unix_sock(sock, buf, len);
699 }
700
701 /*
702 * Process the command requested by the lttng client within the command
703 * context structure. This function make sure that the return structure (llm)
704 * is set and ready for transmission before returning.
705 *
706 * Return any error encountered or 0 for success.
707 *
708 * "sock" is only used for special-case var. len data.
709 * A command may assume the ownership of the socket, in which case its value
710 * should be set to -1.
711 *
712 * Should *NOT* be called with RCU read-side lock held.
713 */
714 static int process_client_msg(struct command_ctx *cmd_ctx, int *sock,
715 int *sock_error)
716 {
717 int ret = LTTNG_OK;
718 int need_tracing_session = 1;
719 int need_domain;
720 struct lttng_dynamic_buffer payload;
721
722 lttng_dynamic_buffer_init(&payload);
723
724 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
725
726 assert(!rcu_read_ongoing());
727
728 *sock_error = 0;
729
730 switch (cmd_ctx->lsm->cmd_type) {
731 case LTTNG_CREATE_SESSION_EXT:
732 case LTTNG_DESTROY_SESSION:
733 case LTTNG_LIST_SESSIONS:
734 case LTTNG_LIST_DOMAINS:
735 case LTTNG_START_TRACE:
736 case LTTNG_STOP_TRACE:
737 case LTTNG_DATA_PENDING:
738 case LTTNG_SNAPSHOT_ADD_OUTPUT:
739 case LTTNG_SNAPSHOT_DEL_OUTPUT:
740 case LTTNG_SNAPSHOT_LIST_OUTPUT:
741 case LTTNG_SNAPSHOT_RECORD:
742 case LTTNG_SAVE_SESSION:
743 case LTTNG_SET_SESSION_SHM_PATH:
744 case LTTNG_REGENERATE_METADATA:
745 case LTTNG_REGENERATE_STATEDUMP:
746 case LTTNG_REGISTER_TRIGGER:
747 case LTTNG_UNREGISTER_TRIGGER:
748 case LTTNG_ROTATE_SESSION:
749 case LTTNG_ROTATION_GET_INFO:
750 case LTTNG_ROTATION_SET_SCHEDULE:
751 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
752 case LTTNG_CLEAR_SESSION:
753 need_domain = 0;
754 break;
755 default:
756 need_domain = 1;
757 }
758
759 if (config.no_kernel && need_domain
760 && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
761 if (!is_root) {
762 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
763 } else {
764 ret = LTTNG_ERR_KERN_NA;
765 }
766 goto error;
767 }
768
769 /* Deny register consumer if we already have a spawned consumer. */
770 if (cmd_ctx->lsm->cmd_type == LTTNG_REGISTER_CONSUMER) {
771 pthread_mutex_lock(&kconsumer_data.pid_mutex);
772 if (kconsumer_data.pid > 0) {
773 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
774 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
775 goto error;
776 }
777 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
778 }
779
780 /*
781 * Check for command that don't needs to allocate a returned payload. We do
782 * this here so we don't have to make the call for no payload at each
783 * command.
784 */
785 switch(cmd_ctx->lsm->cmd_type) {
786 case LTTNG_LIST_SESSIONS:
787 case LTTNG_LIST_TRACEPOINTS:
788 case LTTNG_LIST_TRACEPOINT_FIELDS:
789 case LTTNG_LIST_DOMAINS:
790 case LTTNG_LIST_CHANNELS:
791 case LTTNG_LIST_EVENTS:
792 case LTTNG_LIST_SYSCALLS:
793 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
794 case LTTNG_PROCESS_ATTR_TRACKER_GET_POLICY:
795 case LTTNG_PROCESS_ATTR_TRACKER_GET_INCLUSION_SET:
796 case LTTNG_DATA_PENDING:
797 case LTTNG_ROTATE_SESSION:
798 case LTTNG_ROTATION_GET_INFO:
799 break;
800 default:
801 /* Setup lttng message with no payload */
802 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0);
803 if (ret < 0) {
804 /* This label does not try to unlock the session */
805 goto init_setup_error;
806 }
807 }
808
809 /* Commands that DO NOT need a session. */
810 switch (cmd_ctx->lsm->cmd_type) {
811 case LTTNG_CREATE_SESSION_EXT:
812 case LTTNG_LIST_SESSIONS:
813 case LTTNG_LIST_TRACEPOINTS:
814 case LTTNG_LIST_SYSCALLS:
815 case LTTNG_LIST_TRACEPOINT_FIELDS:
816 case LTTNG_SAVE_SESSION:
817 case LTTNG_REGISTER_TRIGGER:
818 case LTTNG_UNREGISTER_TRIGGER:
819 need_tracing_session = 0;
820 break;
821 default:
822 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
823 /*
824 * We keep the session list lock across _all_ commands
825 * for now, because the per-session lock does not
826 * handle teardown properly.
827 */
828 session_lock_list();
829 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
830 if (cmd_ctx->session == NULL) {
831 ret = LTTNG_ERR_SESS_NOT_FOUND;
832 goto error;
833 } else {
834 /* Acquire lock for the session */
835 session_lock(cmd_ctx->session);
836 }
837 break;
838 }
839
840 /*
841 * Commands that need a valid session but should NOT create one if none
842 * exists. Instead of creating one and destroying it when the command is
843 * handled, process that right before so we save some round trip in useless
844 * code path.
845 */
846 switch (cmd_ctx->lsm->cmd_type) {
847 case LTTNG_DISABLE_CHANNEL:
848 case LTTNG_DISABLE_EVENT:
849 switch (cmd_ctx->lsm->domain.type) {
850 case LTTNG_DOMAIN_KERNEL:
851 if (!cmd_ctx->session->kernel_session) {
852 ret = LTTNG_ERR_NO_CHANNEL;
853 goto error;
854 }
855 break;
856 case LTTNG_DOMAIN_JUL:
857 case LTTNG_DOMAIN_LOG4J:
858 case LTTNG_DOMAIN_PYTHON:
859 case LTTNG_DOMAIN_UST:
860 if (!cmd_ctx->session->ust_session) {
861 ret = LTTNG_ERR_NO_CHANNEL;
862 goto error;
863 }
864 break;
865 default:
866 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
867 goto error;
868 }
869 default:
870 break;
871 }
872
873 if (!need_domain) {
874 goto skip_domain;
875 }
876
877 /*
878 * Check domain type for specific "pre-action".
879 */
880 switch (cmd_ctx->lsm->domain.type) {
881 case LTTNG_DOMAIN_KERNEL:
882 if (!is_root) {
883 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
884 goto error;
885 }
886
887 /* Kernel tracer check */
888 if (!kernel_tracer_is_initialized()) {
889 /* Basically, load kernel tracer modules */
890 ret = init_kernel_tracer();
891 if (ret != 0) {
892 goto error;
893 }
894 }
895
896 /* Consumer is in an ERROR state. Report back to client */
897 if (uatomic_read(&kernel_consumerd_state) == CONSUMER_ERROR) {
898 ret = LTTNG_ERR_NO_KERNCONSUMERD;
899 goto error;
900 }
901
902 /* Need a session for kernel command */
903 if (need_tracing_session) {
904 if (cmd_ctx->session->kernel_session == NULL) {
905 ret = create_kernel_session(cmd_ctx->session);
906 if (ret != LTTNG_OK) {
907 ret = LTTNG_ERR_KERN_SESS_FAIL;
908 goto error;
909 }
910 }
911
912 /* Start the kernel consumer daemon */
913 pthread_mutex_lock(&kconsumer_data.pid_mutex);
914 if (kconsumer_data.pid == 0 &&
915 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
916 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
917 ret = start_consumerd(&kconsumer_data);
918 if (ret < 0) {
919 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
920 goto error;
921 }
922 uatomic_set(&kernel_consumerd_state, CONSUMER_STARTED);
923 } else {
924 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
925 }
926
927 /*
928 * The consumer was just spawned so we need to add the socket to
929 * the consumer output of the session if exist.
930 */
931 ret = consumer_create_socket(&kconsumer_data,
932 cmd_ctx->session->kernel_session->consumer);
933 if (ret < 0) {
934 goto error;
935 }
936 }
937
938 break;
939 case LTTNG_DOMAIN_JUL:
940 case LTTNG_DOMAIN_LOG4J:
941 case LTTNG_DOMAIN_PYTHON:
942 case LTTNG_DOMAIN_UST:
943 {
944 if (!ust_app_supported()) {
945 ret = LTTNG_ERR_NO_UST;
946 goto error;
947 }
948 /* Consumer is in an ERROR state. Report back to client */
949 if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) {
950 ret = LTTNG_ERR_NO_USTCONSUMERD;
951 goto error;
952 }
953
954 if (need_tracing_session) {
955 /* Create UST session if none exist. */
956 if (cmd_ctx->session->ust_session == NULL) {
957 ret = create_ust_session(cmd_ctx->session,
958 ALIGNED_CONST_PTR(cmd_ctx->lsm->domain));
959 if (ret != LTTNG_OK) {
960 goto error;
961 }
962 }
963
964 /* Start the UST consumer daemons */
965 /* 64-bit */
966 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
967 if (config.consumerd64_bin_path.value &&
968 ustconsumer64_data.pid == 0 &&
969 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
970 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
971 ret = start_consumerd(&ustconsumer64_data);
972 if (ret < 0) {
973 ret = LTTNG_ERR_UST_CONSUMER64_FAIL;
974 uatomic_set(&ust_consumerd64_fd, -EINVAL);
975 goto error;
976 }
977
978 uatomic_set(&ust_consumerd64_fd, ustconsumer64_data.cmd_sock);
979 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
980 } else {
981 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
982 }
983
984 /*
985 * Setup socket for consumer 64 bit. No need for atomic access
986 * since it was set above and can ONLY be set in this thread.
987 */
988 ret = consumer_create_socket(&ustconsumer64_data,
989 cmd_ctx->session->ust_session->consumer);
990 if (ret < 0) {
991 goto error;
992 }
993
994 /* 32-bit */
995 pthread_mutex_lock(&ustconsumer32_data.pid_mutex);
996 if (config.consumerd32_bin_path.value &&
997 ustconsumer32_data.pid == 0 &&
998 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
999 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
1000 ret = start_consumerd(&ustconsumer32_data);
1001 if (ret < 0) {
1002 ret = LTTNG_ERR_UST_CONSUMER32_FAIL;
1003 uatomic_set(&ust_consumerd32_fd, -EINVAL);
1004 goto error;
1005 }
1006
1007 uatomic_set(&ust_consumerd32_fd, ustconsumer32_data.cmd_sock);
1008 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
1009 } else {
1010 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
1011 }
1012
1013 /*
1014 * Setup socket for consumer 32 bit. No need for atomic access
1015 * since it was set above and can ONLY be set in this thread.
1016 */
1017 ret = consumer_create_socket(&ustconsumer32_data,
1018 cmd_ctx->session->ust_session->consumer);
1019 if (ret < 0) {
1020 goto error;
1021 }
1022 }
1023 break;
1024 }
1025 default:
1026 break;
1027 }
1028 skip_domain:
1029
1030 /* Validate consumer daemon state when start/stop trace command */
1031 if (cmd_ctx->lsm->cmd_type == LTTNG_START_TRACE ||
1032 cmd_ctx->lsm->cmd_type == LTTNG_STOP_TRACE) {
1033 switch (cmd_ctx->lsm->domain.type) {
1034 case LTTNG_DOMAIN_NONE:
1035 break;
1036 case LTTNG_DOMAIN_JUL:
1037 case LTTNG_DOMAIN_LOG4J:
1038 case LTTNG_DOMAIN_PYTHON:
1039 case LTTNG_DOMAIN_UST:
1040 if (uatomic_read(&ust_consumerd_state) != CONSUMER_STARTED) {
1041 ret = LTTNG_ERR_NO_USTCONSUMERD;
1042 goto error;
1043 }
1044 break;
1045 case LTTNG_DOMAIN_KERNEL:
1046 if (uatomic_read(&kernel_consumerd_state) != CONSUMER_STARTED) {
1047 ret = LTTNG_ERR_NO_KERNCONSUMERD;
1048 goto error;
1049 }
1050 break;
1051 default:
1052 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1053 goto error;
1054 }
1055 }
1056
1057 /*
1058 * Check that the UID or GID match that of the tracing session.
1059 * The root user can interact with all sessions.
1060 */
1061 if (need_tracing_session) {
1062 if (!session_access_ok(cmd_ctx->session,
1063 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1064 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds)) ||
1065 cmd_ctx->session->destroyed) {
1066 ret = LTTNG_ERR_EPERM;
1067 goto error;
1068 }
1069 }
1070
1071 /*
1072 * Send relayd information to consumer as soon as we have a domain and a
1073 * session defined.
1074 */
1075 if (cmd_ctx->session && need_domain) {
1076 /*
1077 * Setup relayd if not done yet. If the relayd information was already
1078 * sent to the consumer, this call will gracefully return.
1079 */
1080 ret = cmd_setup_relayd(cmd_ctx->session);
1081 if (ret != LTTNG_OK) {
1082 goto error;
1083 }
1084 }
1085
1086 /* Process by command type */
1087 switch (cmd_ctx->lsm->cmd_type) {
1088 case LTTNG_ADD_CONTEXT:
1089 {
1090 /*
1091 * An LTTNG_ADD_CONTEXT command might have a supplementary
1092 * payload if the context being added is an application context.
1093 */
1094 if (cmd_ctx->lsm->u.context.ctx.ctx ==
1095 LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1096 char *provider_name = NULL, *context_name = NULL;
1097 size_t provider_name_len =
1098 cmd_ctx->lsm->u.context.provider_name_len;
1099 size_t context_name_len =
1100 cmd_ctx->lsm->u.context.context_name_len;
1101
1102 if (provider_name_len == 0 || context_name_len == 0) {
1103 /*
1104 * Application provider and context names MUST
1105 * be provided.
1106 */
1107 ret = -LTTNG_ERR_INVALID;
1108 goto error;
1109 }
1110
1111 provider_name = zmalloc(provider_name_len + 1);
1112 if (!provider_name) {
1113 ret = -LTTNG_ERR_NOMEM;
1114 goto error;
1115 }
1116 cmd_ctx->lsm->u.context.ctx.u.app_ctx.provider_name =
1117 provider_name;
1118
1119 context_name = zmalloc(context_name_len + 1);
1120 if (!context_name) {
1121 ret = -LTTNG_ERR_NOMEM;
1122 goto error_add_context;
1123 }
1124 cmd_ctx->lsm->u.context.ctx.u.app_ctx.ctx_name =
1125 context_name;
1126
1127 ret = lttcomm_recv_unix_sock(*sock, provider_name,
1128 provider_name_len);
1129 if (ret < 0) {
1130 goto error_add_context;
1131 }
1132
1133 ret = lttcomm_recv_unix_sock(*sock, context_name,
1134 context_name_len);
1135 if (ret < 0) {
1136 goto error_add_context;
1137 }
1138 }
1139
1140 /*
1141 * cmd_add_context assumes ownership of the provider and context
1142 * names.
1143 */
1144 ret = cmd_add_context(cmd_ctx->session,
1145 cmd_ctx->lsm->domain.type,
1146 cmd_ctx->lsm->u.context.channel_name,
1147 ALIGNED_CONST_PTR(cmd_ctx->lsm->u.context.ctx),
1148 kernel_poll_pipe[1]);
1149
1150 cmd_ctx->lsm->u.context.ctx.u.app_ctx.provider_name = NULL;
1151 cmd_ctx->lsm->u.context.ctx.u.app_ctx.ctx_name = NULL;
1152 error_add_context:
1153 free(cmd_ctx->lsm->u.context.ctx.u.app_ctx.provider_name);
1154 free(cmd_ctx->lsm->u.context.ctx.u.app_ctx.ctx_name);
1155 if (ret < 0) {
1156 goto error;
1157 }
1158 break;
1159 }
1160 case LTTNG_DISABLE_CHANNEL:
1161 {
1162 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
1163 cmd_ctx->lsm->u.disable.channel_name);
1164 break;
1165 }
1166 case LTTNG_DISABLE_EVENT:
1167 {
1168
1169 /*
1170 * FIXME: handle filter; for now we just receive the filter's
1171 * bytecode along with the filter expression which are sent by
1172 * liblttng-ctl and discard them.
1173 *
1174 * This fixes an issue where the client may block while sending
1175 * the filter payload and encounter an error because the session
1176 * daemon closes the socket without ever handling this data.
1177 */
1178 size_t count = cmd_ctx->lsm->u.disable.expression_len +
1179 cmd_ctx->lsm->u.disable.bytecode_len;
1180
1181 if (count) {
1182 char data[LTTNG_FILTER_MAX_LEN];
1183
1184 DBG("Discarding disable event command payload of size %zu", count);
1185 while (count) {
1186 ret = lttcomm_recv_unix_sock(*sock, data,
1187 count > sizeof(data) ? sizeof(data) : count);
1188 if (ret < 0) {
1189 goto error;
1190 }
1191
1192 count -= (size_t) ret;
1193 }
1194 }
1195 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
1196 cmd_ctx->lsm->u.disable.channel_name,
1197 ALIGNED_CONST_PTR(cmd_ctx->lsm->u.disable.event));
1198 break;
1199 }
1200 case LTTNG_ENABLE_CHANNEL:
1201 {
1202 ret = cmd_enable_channel(cmd_ctx, *sock, kernel_poll_pipe[1]);
1203 break;
1204 }
1205 case LTTNG_PROCESS_ATTR_TRACKER_ADD_INCLUDE_VALUE:
1206 case LTTNG_PROCESS_ATTR_TRACKER_REMOVE_INCLUDE_VALUE:
1207 {
1208 struct lttng_dynamic_buffer payload;
1209 struct lttng_buffer_view payload_view;
1210 const bool add_value =
1211 cmd_ctx->lsm->cmd_type ==
1212 LTTNG_PROCESS_ATTR_TRACKER_ADD_INCLUDE_VALUE;
1213 const size_t name_len =
1214 cmd_ctx->lsm->u.process_attr_tracker_add_remove_include_value
1215 .name_len;
1216 const enum lttng_domain_type domain_type =
1217 (enum lttng_domain_type)
1218 cmd_ctx->lsm->domain.type;
1219 const enum lttng_process_attr process_attr =
1220 (enum lttng_process_attr) cmd_ctx->lsm->u
1221 .process_attr_tracker_add_remove_include_value
1222 .process_attr;
1223 const enum lttng_process_attr_value_type value_type =
1224 (enum lttng_process_attr_value_type) cmd_ctx
1225 ->lsm->u
1226 .process_attr_tracker_add_remove_include_value
1227 .value_type;
1228 struct process_attr_value *value;
1229 enum lttng_error_code ret_code;
1230
1231 /* Receive remaining variable length payload if applicable. */
1232 if (name_len > LOGIN_NAME_MAX) {
1233 /*
1234 * POSIX mandates user and group names that are at least
1235 * 8 characters long. Note that although shadow-utils
1236 * (useradd, groupaadd, etc.) use 32 chars as their
1237 * limit (from bits/utmp.h, UT_NAMESIZE),
1238 * LOGIN_NAME_MAX is defined to 256.
1239 */
1240 ERR("Rejecting process attribute tracker value %s as the provided exceeds the maximal allowed length: argument length = %zu, maximal length = %d",
1241 add_value ? "addition" : "removal",
1242 name_len, LOGIN_NAME_MAX);
1243 ret = LTTNG_ERR_INVALID;
1244 goto error;
1245 }
1246
1247 lttng_dynamic_buffer_init(&payload);
1248 if (name_len != 0) {
1249 /*
1250 * Receive variable payload for user/group name
1251 * arguments.
1252 */
1253 ret = lttng_dynamic_buffer_set_size(&payload, name_len);
1254 if (ret) {
1255 ERR("Failed to allocate buffer to receive payload of %s process attribute tracker value argument",
1256 add_value ? "add" : "remove");
1257 ret = LTTNG_ERR_NOMEM;
1258 goto error_add_remove_tracker_value;
1259 }
1260
1261 ret = lttcomm_recv_unix_sock(
1262 *sock, payload.data, name_len);
1263 if (ret <= 0) {
1264 ERR("Failed to receive payload of %s process attribute tracker value argument",
1265 add_value ? "add" : "remove");
1266 *sock_error = 1;
1267 ret = LTTNG_ERR_INVALID_PROTOCOL;
1268 goto error_add_remove_tracker_value;
1269 }
1270 }
1271
1272 payload_view = lttng_buffer_view_from_dynamic_buffer(
1273 &payload, 0, name_len);
1274 /*
1275 * Validate the value type and domains are legal for the process
1276 * attribute tracker that is specified and convert the value to
1277 * add/remove to the internal sessiond representation.
1278 */
1279 ret_code = process_attr_value_from_comm(domain_type,
1280 process_attr, value_type,
1281 &cmd_ctx->lsm->u.process_attr_tracker_add_remove_include_value
1282 .integral_value,
1283 &payload_view, &value);
1284 if (ret_code != LTTNG_OK) {
1285 ret = ret_code;
1286 goto error_add_remove_tracker_value;
1287 }
1288
1289 if (add_value) {
1290 ret = cmd_process_attr_tracker_inclusion_set_add_value(
1291 cmd_ctx->session, domain_type,
1292 process_attr, value);
1293 } else {
1294 ret = cmd_process_attr_tracker_inclusion_set_remove_value(
1295 cmd_ctx->session, domain_type,
1296 process_attr, value);
1297 }
1298 process_attr_value_destroy(value);
1299 error_add_remove_tracker_value:
1300 lttng_dynamic_buffer_reset(&payload);
1301 break;
1302 }
1303 case LTTNG_PROCESS_ATTR_TRACKER_GET_POLICY:
1304 {
1305 enum lttng_tracking_policy tracking_policy;
1306 const enum lttng_domain_type domain_type =
1307 (enum lttng_domain_type)
1308 cmd_ctx->lsm->domain.type;
1309 const enum lttng_process_attr process_attr =
1310 (enum lttng_process_attr) cmd_ctx->lsm->u
1311 .process_attr_tracker_get_tracking_policy
1312 .process_attr;
1313
1314 ret = cmd_process_attr_tracker_get_tracking_policy(
1315 cmd_ctx->session, domain_type, process_attr,
1316 &tracking_policy);
1317 if (ret != LTTNG_OK) {
1318 goto error;
1319 }
1320
1321 ret = setup_lttng_msg_no_cmd_header(cmd_ctx,
1322 &(uint32_t){tracking_policy}, sizeof(uint32_t));
1323 if (ret < 0) {
1324 ret = LTTNG_ERR_NOMEM;
1325 goto error;
1326 }
1327 ret = LTTNG_OK;
1328 break;
1329 }
1330 case LTTNG_PROCESS_ATTR_TRACKER_SET_POLICY:
1331 {
1332 const enum lttng_tracking_policy tracking_policy =
1333 (enum lttng_tracking_policy) cmd_ctx->lsm->u
1334 .process_attr_tracker_set_tracking_policy
1335 .tracking_policy;
1336 const enum lttng_domain_type domain_type =
1337 (enum lttng_domain_type)
1338 cmd_ctx->lsm->domain.type;
1339 const enum lttng_process_attr process_attr =
1340 (enum lttng_process_attr) cmd_ctx->lsm->u
1341 .process_attr_tracker_set_tracking_policy
1342 .process_attr;
1343
1344 ret = cmd_process_attr_tracker_set_tracking_policy(
1345 cmd_ctx->session, domain_type, process_attr,
1346 tracking_policy);
1347 if (ret != LTTNG_OK) {
1348 goto error;
1349 }
1350 break;
1351 }
1352 case LTTNG_PROCESS_ATTR_TRACKER_GET_INCLUSION_SET:
1353 {
1354 struct lttng_process_attr_values *values;
1355 struct lttng_dynamic_buffer reply;
1356 const enum lttng_domain_type domain_type =
1357 (enum lttng_domain_type)
1358 cmd_ctx->lsm->domain.type;
1359 const enum lttng_process_attr process_attr =
1360 (enum lttng_process_attr) cmd_ctx->lsm->u
1361 .process_attr_tracker_get_inclusion_set
1362 .process_attr;
1363
1364 ret = cmd_process_attr_tracker_get_inclusion_set(
1365 cmd_ctx->session, domain_type, process_attr,
1366 &values);
1367 if (ret != LTTNG_OK) {
1368 goto error;
1369 }
1370
1371 lttng_dynamic_buffer_init(&reply);
1372 ret = lttng_process_attr_values_serialize(values, &reply);
1373 if (ret < 0) {
1374 goto error_tracker_get_inclusion_set;
1375 }
1376
1377 ret = setup_lttng_msg_no_cmd_header(
1378 cmd_ctx, reply.data, reply.size);
1379 if (ret < 0) {
1380 ret = LTTNG_ERR_NOMEM;
1381 goto error_tracker_get_inclusion_set;
1382 }
1383 ret = LTTNG_OK;
1384
1385 error_tracker_get_inclusion_set:
1386 lttng_process_attr_values_destroy(values);
1387 lttng_dynamic_buffer_reset(&reply);
1388 break;
1389 }
1390 case LTTNG_ENABLE_EVENT:
1391 {
1392 struct lttng_event *ev = NULL;
1393 struct lttng_event_exclusion *exclusion = NULL;
1394 struct lttng_filter_bytecode *bytecode = NULL;
1395 char *filter_expression = NULL;
1396
1397 /* Handle exclusion events and receive it from the client. */
1398 if (cmd_ctx->lsm->u.enable.exclusion_count > 0) {
1399 size_t count = cmd_ctx->lsm->u.enable.exclusion_count;
1400
1401 exclusion = zmalloc(sizeof(struct lttng_event_exclusion) +
1402 (count * LTTNG_SYMBOL_NAME_LEN));
1403 if (!exclusion) {
1404 ret = LTTNG_ERR_EXCLUSION_NOMEM;
1405 goto error;
1406 }
1407
1408 DBG("Receiving var len exclusion event list from client ...");
1409 exclusion->count = count;
1410 ret = lttcomm_recv_unix_sock(*sock, exclusion->names,
1411 count * LTTNG_SYMBOL_NAME_LEN);
1412 if (ret <= 0) {
1413 DBG("Nothing recv() from client var len data... continuing");
1414 *sock_error = 1;
1415 free(exclusion);
1416 ret = LTTNG_ERR_EXCLUSION_INVAL;
1417 goto error;
1418 }
1419 }
1420
1421 /* Get filter expression from client. */
1422 if (cmd_ctx->lsm->u.enable.expression_len > 0) {
1423 size_t expression_len =
1424 cmd_ctx->lsm->u.enable.expression_len;
1425
1426 if (expression_len > LTTNG_FILTER_MAX_LEN) {
1427 ret = LTTNG_ERR_FILTER_INVAL;
1428 free(exclusion);
1429 goto error;
1430 }
1431
1432 filter_expression = zmalloc(expression_len);
1433 if (!filter_expression) {
1434 free(exclusion);
1435 ret = LTTNG_ERR_FILTER_NOMEM;
1436 goto error;
1437 }
1438
1439 /* Receive var. len. data */
1440 DBG("Receiving var len filter's expression from client ...");
1441 ret = lttcomm_recv_unix_sock(*sock, filter_expression,
1442 expression_len);
1443 if (ret <= 0) {
1444 DBG("Nothing recv() from client var len data... continuing");
1445 *sock_error = 1;
1446 free(filter_expression);
1447 free(exclusion);
1448 ret = LTTNG_ERR_FILTER_INVAL;
1449 goto error;
1450 }
1451 }
1452
1453 /* Handle filter and get bytecode from client. */
1454 if (cmd_ctx->lsm->u.enable.bytecode_len > 0) {
1455 size_t bytecode_len = cmd_ctx->lsm->u.enable.bytecode_len;
1456
1457 if (bytecode_len > LTTNG_FILTER_MAX_LEN) {
1458 ret = LTTNG_ERR_FILTER_INVAL;
1459 free(filter_expression);
1460 free(exclusion);
1461 goto error;
1462 }
1463
1464 bytecode = zmalloc(bytecode_len);
1465 if (!bytecode) {
1466 free(filter_expression);
1467 free(exclusion);
1468 ret = LTTNG_ERR_FILTER_NOMEM;
1469 goto error;
1470 }
1471
1472 /* Receive var. len. data */
1473 DBG("Receiving var len filter's bytecode from client ...");
1474 ret = lttcomm_recv_unix_sock(*sock, bytecode, bytecode_len);
1475 if (ret <= 0) {
1476 DBG("Nothing recv() from client var len data... continuing");
1477 *sock_error = 1;
1478 free(filter_expression);
1479 free(bytecode);
1480 free(exclusion);
1481 ret = LTTNG_ERR_FILTER_INVAL;
1482 goto error;
1483 }
1484
1485 if ((bytecode->len + sizeof(*bytecode)) != bytecode_len) {
1486 free(filter_expression);
1487 free(bytecode);
1488 free(exclusion);
1489 ret = LTTNG_ERR_FILTER_INVAL;
1490 goto error;
1491 }
1492 }
1493
1494 ev = lttng_event_copy(ALIGNED_CONST_PTR(cmd_ctx->lsm->u.enable.event));
1495 if (!ev) {
1496 DBG("Failed to copy event: %s",
1497 cmd_ctx->lsm->u.enable.event.name);
1498 free(filter_expression);
1499 free(bytecode);
1500 free(exclusion);
1501 ret = LTTNG_ERR_NOMEM;
1502 goto error;
1503 }
1504
1505
1506 if (cmd_ctx->lsm->u.enable.userspace_probe_location_len > 0) {
1507 /* Expect a userspace probe description. */
1508 ret = receive_userspace_probe(cmd_ctx, *sock, sock_error, ev);
1509 if (ret) {
1510 free(filter_expression);
1511 free(bytecode);
1512 free(exclusion);
1513 lttng_event_destroy(ev);
1514 goto error;
1515 }
1516 }
1517
1518 ret = cmd_enable_event(cmd_ctx->session,
1519 ALIGNED_CONST_PTR(cmd_ctx->lsm->domain),
1520 cmd_ctx->lsm->u.enable.channel_name,
1521 ev,
1522 filter_expression, bytecode, exclusion,
1523 kernel_poll_pipe[1]);
1524 lttng_event_destroy(ev);
1525 break;
1526 }
1527 case LTTNG_LIST_TRACEPOINTS:
1528 {
1529 struct lttng_event *events;
1530 ssize_t nb_events;
1531
1532 session_lock_list();
1533 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
1534 session_unlock_list();
1535 if (nb_events < 0) {
1536 /* Return value is a negative lttng_error_code. */
1537 ret = -nb_events;
1538 goto error;
1539 }
1540
1541 /*
1542 * Setup lttng message with payload size set to the event list size in
1543 * bytes and then copy list into the llm payload.
1544 */
1545 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, events,
1546 sizeof(struct lttng_event) * nb_events);
1547 free(events);
1548
1549 if (ret < 0) {
1550 goto setup_error;
1551 }
1552
1553 ret = LTTNG_OK;
1554 break;
1555 }
1556 case LTTNG_LIST_TRACEPOINT_FIELDS:
1557 {
1558 struct lttng_event_field *fields;
1559 ssize_t nb_fields;
1560
1561 session_lock_list();
1562 nb_fields = cmd_list_tracepoint_fields(cmd_ctx->lsm->domain.type,
1563 &fields);
1564 session_unlock_list();
1565 if (nb_fields < 0) {
1566 /* Return value is a negative lttng_error_code. */
1567 ret = -nb_fields;
1568 goto error;
1569 }
1570
1571 /*
1572 * Setup lttng message with payload size set to the event list size in
1573 * bytes and then copy list into the llm payload.
1574 */
1575 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, fields,
1576 sizeof(struct lttng_event_field) * nb_fields);
1577 free(fields);
1578
1579 if (ret < 0) {
1580 goto setup_error;
1581 }
1582
1583 ret = LTTNG_OK;
1584 break;
1585 }
1586 case LTTNG_LIST_SYSCALLS:
1587 {
1588 struct lttng_event *events;
1589 ssize_t nb_events;
1590
1591 nb_events = cmd_list_syscalls(&events);
1592 if (nb_events < 0) {
1593 /* Return value is a negative lttng_error_code. */
1594 ret = -nb_events;
1595 goto error;
1596 }
1597
1598 /*
1599 * Setup lttng message with payload size set to the event list size in
1600 * bytes and then copy list into the llm payload.
1601 */
1602 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, events,
1603 sizeof(struct lttng_event) * nb_events);
1604 free(events);
1605
1606 if (ret < 0) {
1607 goto setup_error;
1608 }
1609
1610 ret = LTTNG_OK;
1611 break;
1612 }
1613 case LTTNG_SET_CONSUMER_URI:
1614 {
1615 size_t nb_uri, len;
1616 struct lttng_uri *uris;
1617
1618 nb_uri = cmd_ctx->lsm->u.uri.size;
1619 len = nb_uri * sizeof(struct lttng_uri);
1620
1621 if (nb_uri == 0) {
1622 ret = LTTNG_ERR_INVALID;
1623 goto error;
1624 }
1625
1626 uris = zmalloc(len);
1627 if (uris == NULL) {
1628 ret = LTTNG_ERR_FATAL;
1629 goto error;
1630 }
1631
1632 /* Receive variable len data */
1633 DBG("Receiving %zu URI(s) from client ...", nb_uri);
1634 ret = lttcomm_recv_unix_sock(*sock, uris, len);
1635 if (ret <= 0) {
1636 DBG("No URIs received from client... continuing");
1637 *sock_error = 1;
1638 ret = LTTNG_ERR_SESSION_FAIL;
1639 free(uris);
1640 goto error;
1641 }
1642
1643 ret = cmd_set_consumer_uri(cmd_ctx->session, nb_uri, uris);
1644 free(uris);
1645 if (ret != LTTNG_OK) {
1646 goto error;
1647 }
1648
1649
1650 break;
1651 }
1652 case LTTNG_START_TRACE:
1653 {
1654 /*
1655 * On the first start, if we have a kernel session and we have
1656 * enabled time or size-based rotations, we have to make sure
1657 * the kernel tracer supports it.
1658 */
1659 if (!cmd_ctx->session->has_been_started && \
1660 cmd_ctx->session->kernel_session && \
1661 (cmd_ctx->session->rotate_timer_period || \
1662 cmd_ctx->session->rotate_size) && \
1663 !check_rotate_compatible()) {
1664 DBG("Kernel tracer version is not compatible with the rotation feature");
1665 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
1666 goto error;
1667 }
1668 ret = cmd_start_trace(cmd_ctx->session);
1669 break;
1670 }
1671 case LTTNG_STOP_TRACE:
1672 {
1673 ret = cmd_stop_trace(cmd_ctx->session);
1674 break;
1675 }
1676 case LTTNG_DESTROY_SESSION:
1677 {
1678 ret = cmd_destroy_session(cmd_ctx->session,
1679 notification_thread_handle,
1680 sock);
1681 break;
1682 }
1683 case LTTNG_LIST_DOMAINS:
1684 {
1685 ssize_t nb_dom;
1686 struct lttng_domain *domains = NULL;
1687
1688 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
1689 if (nb_dom < 0) {
1690 /* Return value is a negative lttng_error_code. */
1691 ret = -nb_dom;
1692 goto error;
1693 }
1694
1695 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, domains,
1696 nb_dom * sizeof(struct lttng_domain));
1697 free(domains);
1698
1699 if (ret < 0) {
1700 goto setup_error;
1701 }
1702
1703 ret = LTTNG_OK;
1704 break;
1705 }
1706 case LTTNG_LIST_CHANNELS:
1707 {
1708 uint32_t nb_channel;
1709 enum lttng_error_code ret_code;
1710 struct lttcomm_list_command_header cmd_header = { 0 };
1711
1712 ret_code = cmd_list_channels(cmd_ctx->lsm->domain.type,
1713 cmd_ctx->session, &payload, &nb_channel);
1714 if (ret_code != LTTNG_OK) {
1715 ret = (int) ret_code;
1716 goto error;
1717 }
1718
1719 cmd_header.count = nb_channel;
1720 ret = setup_lttng_msg(cmd_ctx, payload.data, payload.size,
1721 &cmd_header, sizeof(cmd_header));
1722
1723 if (ret < 0) {
1724 goto setup_error;
1725 }
1726
1727 ret = LTTNG_OK;
1728 break;
1729 }
1730 case LTTNG_LIST_EVENTS:
1731 {
1732 ssize_t nb_event;
1733 struct lttng_event *events = NULL;
1734 struct lttcomm_event_command_header cmd_header;
1735 size_t total_size;
1736
1737 memset(&cmd_header, 0, sizeof(cmd_header));
1738 /* Extended infos are included at the end of events */
1739 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type,
1740 cmd_ctx->session, cmd_ctx->lsm->u.list.channel_name,
1741 &events, &total_size);
1742
1743 if (nb_event < 0) {
1744 /* Return value is a negative lttng_error_code. */
1745 ret = -nb_event;
1746 goto error;
1747 }
1748
1749 cmd_header.nb_events = nb_event;
1750 ret = setup_lttng_msg(cmd_ctx, events, total_size,
1751 &cmd_header, sizeof(cmd_header));
1752 free(events);
1753
1754 if (ret < 0) {
1755 goto setup_error;
1756 }
1757
1758 ret = LTTNG_OK;
1759 break;
1760 }
1761 case LTTNG_LIST_SESSIONS:
1762 {
1763 unsigned int nr_sessions;
1764 void *sessions_payload;
1765 size_t payload_len;
1766
1767 session_lock_list();
1768 nr_sessions = lttng_sessions_count(
1769 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1770 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
1771
1772 payload_len = (sizeof(struct lttng_session) * nr_sessions) +
1773 (sizeof(struct lttng_session_extended) * nr_sessions);
1774 sessions_payload = zmalloc(payload_len);
1775
1776 if (!sessions_payload) {
1777 session_unlock_list();
1778 ret = -ENOMEM;
1779 goto setup_error;
1780 }
1781
1782 cmd_list_lttng_sessions(sessions_payload, nr_sessions,
1783 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1784 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
1785 session_unlock_list();
1786
1787 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, sessions_payload,
1788 payload_len);
1789 free(sessions_payload);
1790
1791 if (ret < 0) {
1792 goto setup_error;
1793 }
1794
1795 ret = LTTNG_OK;
1796 break;
1797 }
1798 case LTTNG_REGISTER_CONSUMER:
1799 {
1800 struct consumer_data *cdata;
1801
1802 switch (cmd_ctx->lsm->domain.type) {
1803 case LTTNG_DOMAIN_KERNEL:
1804 cdata = &kconsumer_data;
1805 break;
1806 default:
1807 ret = LTTNG_ERR_UND;
1808 goto error;
1809 }
1810
1811 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
1812 cmd_ctx->lsm->u.reg.path, cdata);
1813 break;
1814 }
1815 case LTTNG_DATA_PENDING:
1816 {
1817 int pending_ret;
1818 uint8_t pending_ret_byte;
1819
1820 pending_ret = cmd_data_pending(cmd_ctx->session);
1821
1822 /*
1823 * FIXME
1824 *
1825 * This function may returns 0 or 1 to indicate whether or not
1826 * there is data pending. In case of error, it should return an
1827 * LTTNG_ERR code. However, some code paths may still return
1828 * a nondescript error code, which we handle by returning an
1829 * "unknown" error.
1830 */
1831 if (pending_ret == 0 || pending_ret == 1) {
1832 /*
1833 * ret will be set to LTTNG_OK at the end of
1834 * this function.
1835 */
1836 } else if (pending_ret < 0) {
1837 ret = LTTNG_ERR_UNK;
1838 goto setup_error;
1839 } else {
1840 ret = pending_ret;
1841 goto setup_error;
1842 }
1843
1844 pending_ret_byte = (uint8_t) pending_ret;
1845
1846 /* 1 byte to return whether or not data is pending */
1847 ret = setup_lttng_msg_no_cmd_header(cmd_ctx,
1848 &pending_ret_byte, 1);
1849
1850 if (ret < 0) {
1851 goto setup_error;
1852 }
1853
1854 ret = LTTNG_OK;
1855 break;
1856 }
1857 case LTTNG_SNAPSHOT_ADD_OUTPUT:
1858 {
1859 uint32_t snapshot_id;
1860 struct lttcomm_lttng_output_id reply;
1861
1862 ret = cmd_snapshot_add_output(cmd_ctx->session,
1863 ALIGNED_CONST_PTR(cmd_ctx->lsm->u.snapshot_output.output),
1864 &snapshot_id);
1865 if (ret != LTTNG_OK) {
1866 goto error;
1867 }
1868 reply.id = snapshot_id;
1869
1870 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &reply,
1871 sizeof(reply));
1872 if (ret < 0) {
1873 goto setup_error;
1874 }
1875
1876 /* Copy output list into message payload */
1877 ret = LTTNG_OK;
1878 break;
1879 }
1880 case LTTNG_SNAPSHOT_DEL_OUTPUT:
1881 {
1882 ret = cmd_snapshot_del_output(cmd_ctx->session,
1883 ALIGNED_CONST_PTR(cmd_ctx->lsm->u.snapshot_output.output));
1884 break;
1885 }
1886 case LTTNG_SNAPSHOT_LIST_OUTPUT:
1887 {
1888 ssize_t nb_output;
1889 struct lttng_snapshot_output *outputs = NULL;
1890
1891 nb_output = cmd_snapshot_list_outputs(cmd_ctx->session, &outputs);
1892 if (nb_output < 0) {
1893 ret = -nb_output;
1894 goto error;
1895 }
1896
1897 assert((nb_output > 0 && outputs) || nb_output == 0);
1898 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, outputs,
1899 nb_output * sizeof(struct lttng_snapshot_output));
1900 free(outputs);
1901
1902 if (ret < 0) {
1903 goto setup_error;
1904 }
1905
1906 ret = LTTNG_OK;
1907 break;
1908 }
1909 case LTTNG_SNAPSHOT_RECORD:
1910 {
1911 ret = cmd_snapshot_record(cmd_ctx->session,
1912 ALIGNED_CONST_PTR(cmd_ctx->lsm->u.snapshot_record.output),
1913 cmd_ctx->lsm->u.snapshot_record.wait);
1914 break;
1915 }
1916 case LTTNG_CREATE_SESSION_EXT:
1917 {
1918 struct lttng_dynamic_buffer payload;
1919 struct lttng_session_descriptor *return_descriptor = NULL;
1920
1921 lttng_dynamic_buffer_init(&payload);
1922 ret = cmd_create_session(cmd_ctx, *sock, &return_descriptor);
1923 if (ret != LTTNG_OK) {
1924 goto error;
1925 }
1926
1927 ret = lttng_session_descriptor_serialize(return_descriptor,
1928 &payload);
1929 if (ret) {
1930 ERR("Failed to serialize session descriptor in reply to \"create session\" command");
1931 lttng_session_descriptor_destroy(return_descriptor);
1932 ret = LTTNG_ERR_NOMEM;
1933 goto error;
1934 }
1935 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, payload.data,
1936 payload.size);
1937 if (ret) {
1938 lttng_session_descriptor_destroy(return_descriptor);
1939 ret = LTTNG_ERR_NOMEM;
1940 goto error;
1941 }
1942 lttng_dynamic_buffer_reset(&payload);
1943 lttng_session_descriptor_destroy(return_descriptor);
1944 ret = LTTNG_OK;
1945 break;
1946 }
1947 case LTTNG_SAVE_SESSION:
1948 {
1949 ret = cmd_save_sessions(&cmd_ctx->lsm->u.save_session.attr,
1950 &cmd_ctx->creds);
1951 break;
1952 }
1953 case LTTNG_SET_SESSION_SHM_PATH:
1954 {
1955 ret = cmd_set_session_shm_path(cmd_ctx->session,
1956 cmd_ctx->lsm->u.set_shm_path.shm_path);
1957 break;
1958 }
1959 case LTTNG_REGENERATE_METADATA:
1960 {
1961 ret = cmd_regenerate_metadata(cmd_ctx->session);
1962 break;
1963 }
1964 case LTTNG_REGENERATE_STATEDUMP:
1965 {
1966 ret = cmd_regenerate_statedump(cmd_ctx->session);
1967 break;
1968 }
1969 case LTTNG_REGISTER_TRIGGER:
1970 {
1971 ret = cmd_register_trigger(cmd_ctx, *sock,
1972 notification_thread_handle);
1973 break;
1974 }
1975 case LTTNG_UNREGISTER_TRIGGER:
1976 {
1977 ret = cmd_unregister_trigger(cmd_ctx, *sock,
1978 notification_thread_handle);
1979 break;
1980 }
1981 case LTTNG_ROTATE_SESSION:
1982 {
1983 struct lttng_rotate_session_return rotate_return;
1984
1985 DBG("Client rotate session \"%s\"", cmd_ctx->session->name);
1986
1987 memset(&rotate_return, 0, sizeof(rotate_return));
1988 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
1989 DBG("Kernel tracer version is not compatible with the rotation feature");
1990 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
1991 goto error;
1992 }
1993
1994 ret = cmd_rotate_session(cmd_ctx->session, &rotate_return,
1995 false,
1996 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
1997 if (ret < 0) {
1998 ret = -ret;
1999 goto error;
2000 }
2001
2002 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &rotate_return,
2003 sizeof(rotate_return));
2004 if (ret < 0) {
2005 ret = -ret;
2006 goto error;
2007 }
2008
2009 ret = LTTNG_OK;
2010 break;
2011 }
2012 case LTTNG_ROTATION_GET_INFO:
2013 {
2014 struct lttng_rotation_get_info_return get_info_return;
2015
2016 memset(&get_info_return, 0, sizeof(get_info_return));
2017 ret = cmd_rotate_get_info(cmd_ctx->session, &get_info_return,
2018 cmd_ctx->lsm->u.get_rotation_info.rotation_id);
2019 if (ret < 0) {
2020 ret = -ret;
2021 goto error;
2022 }
2023
2024 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &get_info_return,
2025 sizeof(get_info_return));
2026 if (ret < 0) {
2027 ret = -ret;
2028 goto error;
2029 }
2030
2031 ret = LTTNG_OK;
2032 break;
2033 }
2034 case LTTNG_ROTATION_SET_SCHEDULE:
2035 {
2036 bool set_schedule;
2037 enum lttng_rotation_schedule_type schedule_type;
2038 uint64_t value;
2039
2040 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
2041 DBG("Kernel tracer version does not support session rotations");
2042 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
2043 goto error;
2044 }
2045
2046 set_schedule = cmd_ctx->lsm->u.rotation_set_schedule.set == 1;
2047 schedule_type = (enum lttng_rotation_schedule_type) cmd_ctx->lsm->u.rotation_set_schedule.type;
2048 value = cmd_ctx->lsm->u.rotation_set_schedule.value;
2049
2050 ret = cmd_rotation_set_schedule(cmd_ctx->session,
2051 set_schedule,
2052 schedule_type,
2053 value,
2054 notification_thread_handle);
2055 if (ret != LTTNG_OK) {
2056 goto error;
2057 }
2058
2059 break;
2060 }
2061 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
2062 {
2063 struct lttng_session_list_schedules_return schedules = {
2064 .periodic.set = !!cmd_ctx->session->rotate_timer_period,
2065 .periodic.value = cmd_ctx->session->rotate_timer_period,
2066 .size.set = !!cmd_ctx->session->rotate_size,
2067 .size.value = cmd_ctx->session->rotate_size,
2068 };
2069
2070 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &schedules,
2071 sizeof(schedules));
2072 if (ret < 0) {
2073 ret = -ret;
2074 goto error;
2075 }
2076
2077 ret = LTTNG_OK;
2078 break;
2079 }
2080 case LTTNG_CLEAR_SESSION:
2081 {
2082 ret = cmd_clear_session(cmd_ctx->session, sock);
2083 break;
2084 }
2085 default:
2086 ret = LTTNG_ERR_UND;
2087 break;
2088 }
2089
2090 error:
2091 if (cmd_ctx->llm == NULL) {
2092 DBG("Missing llm structure. Allocating one.");
2093 if (setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0) < 0) {
2094 goto setup_error;
2095 }
2096 }
2097 /* Set return code */
2098 cmd_ctx->llm->ret_code = ret;
2099 setup_error:
2100 if (cmd_ctx->session) {
2101 session_unlock(cmd_ctx->session);
2102 session_put(cmd_ctx->session);
2103 cmd_ctx->session = NULL;
2104 }
2105 if (need_tracing_session) {
2106 session_unlock_list();
2107 }
2108 init_setup_error:
2109 assert(!rcu_read_ongoing());
2110 lttng_dynamic_buffer_reset(&payload);
2111 return ret;
2112 }
2113
2114 static int create_client_sock(void)
2115 {
2116 int ret, client_sock;
2117 const mode_t old_umask = umask(0);
2118
2119 /* Create client tool unix socket */
2120 client_sock = lttcomm_create_unix_sock(config.client_unix_sock_path.value);
2121 if (client_sock < 0) {
2122 ERR("Create unix sock failed: %s", config.client_unix_sock_path.value);
2123 ret = -1;
2124 goto end;
2125 }
2126
2127 /* Set the cloexec flag */
2128 ret = utils_set_fd_cloexec(client_sock);
2129 if (ret < 0) {
2130 ERR("Unable to set CLOEXEC flag to the client Unix socket (fd: %d). "
2131 "Continuing but note that the consumer daemon will have a "
2132 "reference to this socket on exec()", client_sock);
2133 }
2134
2135 /* File permission MUST be 660 */
2136 ret = chmod(config.client_unix_sock_path.value, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
2137 if (ret < 0) {
2138 ERR("Set file permissions failed: %s",
2139 config.client_unix_sock_path.value);
2140 PERROR("chmod");
2141 (void) lttcomm_close_unix_sock(client_sock);
2142 ret = -1;
2143 goto end;
2144 }
2145 DBG("Created client socket (fd = %i)", client_sock);
2146 ret = client_sock;
2147 end:
2148 umask(old_umask);
2149 return ret;
2150 }
2151
2152 static void cleanup_client_thread(void *data)
2153 {
2154 struct lttng_pipe *quit_pipe = data;
2155
2156 lttng_pipe_destroy(quit_pipe);
2157 }
2158
2159 static void thread_init_cleanup(void *data)
2160 {
2161 set_thread_status(false);
2162 }
2163
2164 /*
2165 * This thread manage all clients request using the unix client socket for
2166 * communication.
2167 */
2168 static void *thread_manage_clients(void *data)
2169 {
2170 int sock = -1, ret, i, pollfd, err = -1;
2171 int sock_error;
2172 uint32_t revents, nb_fd;
2173 struct command_ctx *cmd_ctx = NULL;
2174 struct lttng_poll_event events;
2175 const int client_sock = thread_state.client_sock;
2176 struct lttng_pipe *quit_pipe = data;
2177 const int thread_quit_pipe_fd = lttng_pipe_get_readfd(quit_pipe);
2178
2179 DBG("[thread] Manage client started");
2180
2181 is_root = (getuid() == 0);
2182
2183 pthread_cleanup_push(thread_init_cleanup, NULL);
2184
2185 rcu_register_thread();
2186
2187 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_CMD);
2188
2189 health_code_update();
2190
2191 ret = lttcomm_listen_unix_sock(client_sock);
2192 if (ret < 0) {
2193 goto error_listen;
2194 }
2195
2196 /*
2197 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2198 * more will be added to this poll set.
2199 */
2200 ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
2201 if (ret < 0) {
2202 goto error_create_poll;
2203 }
2204
2205 /* Add the application registration socket */
2206 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
2207 if (ret < 0) {
2208 goto error;
2209 }
2210
2211 /* Add thread quit pipe */
2212 ret = lttng_poll_add(&events, thread_quit_pipe_fd, LPOLLIN | LPOLLERR);
2213 if (ret < 0) {
2214 goto error;
2215 }
2216
2217 /* Set state as running. */
2218 set_thread_status(true);
2219 pthread_cleanup_pop(0);
2220
2221 /* This testpoint is after we signal readiness to the parent. */
2222 if (testpoint(sessiond_thread_manage_clients)) {
2223 goto error;
2224 }
2225
2226 if (testpoint(sessiond_thread_manage_clients_before_loop)) {
2227 goto error;
2228 }
2229
2230 health_code_update();
2231
2232 while (1) {
2233 const struct cmd_completion_handler *cmd_completion_handler;
2234
2235 DBG("Accepting client command ...");
2236
2237 /* Inifinite blocking call, waiting for transmission */
2238 restart:
2239 health_poll_entry();
2240 ret = lttng_poll_wait(&events, -1);
2241 health_poll_exit();
2242 if (ret < 0) {
2243 /*
2244 * Restart interrupted system call.
2245 */
2246 if (errno == EINTR) {
2247 goto restart;
2248 }
2249 goto error;
2250 }
2251
2252 nb_fd = ret;
2253
2254 for (i = 0; i < nb_fd; i++) {
2255 revents = LTTNG_POLL_GETEV(&events, i);
2256 pollfd = LTTNG_POLL_GETFD(&events, i);
2257
2258 health_code_update();
2259
2260 if (pollfd == thread_quit_pipe_fd) {
2261 err = 0;
2262 goto exit;
2263 } else {
2264 /* Event on the registration socket */
2265 if (revents & LPOLLIN) {
2266 continue;
2267 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2268 ERR("Client socket poll error");
2269 goto error;
2270 } else {
2271 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
2272 goto error;
2273 }
2274 }
2275 }
2276
2277 DBG("Wait for client response");
2278
2279 health_code_update();
2280
2281 sock = lttcomm_accept_unix_sock(client_sock);
2282 if (sock < 0) {
2283 goto error;
2284 }
2285
2286 /*
2287 * Set the CLOEXEC flag. Return code is useless because either way, the
2288 * show must go on.
2289 */
2290 (void) utils_set_fd_cloexec(sock);
2291
2292 /* Set socket option for credentials retrieval */
2293 ret = lttcomm_setsockopt_creds_unix_sock(sock);
2294 if (ret < 0) {
2295 goto error;
2296 }
2297
2298 /* Allocate context command to process the client request */
2299 cmd_ctx = zmalloc(sizeof(struct command_ctx));
2300 if (cmd_ctx == NULL) {
2301 PERROR("zmalloc cmd_ctx");
2302 goto error;
2303 }
2304
2305 /* Allocate data buffer for reception */
2306 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
2307 if (cmd_ctx->lsm == NULL) {
2308 PERROR("zmalloc cmd_ctx->lsm");
2309 goto error;
2310 }
2311
2312 cmd_ctx->llm = NULL;
2313 cmd_ctx->session = NULL;
2314
2315 health_code_update();
2316
2317 /*
2318 * Data is received from the lttng client. The struct
2319 * lttcomm_session_msg (lsm) contains the command and data request of
2320 * the client.
2321 */
2322 DBG("Receiving data from client ...");
2323 ret = lttcomm_recv_creds_unix_sock(sock, cmd_ctx->lsm,
2324 sizeof(struct lttcomm_session_msg), &cmd_ctx->creds);
2325 if (ret <= 0) {
2326 DBG("Nothing recv() from client... continuing");
2327 ret = close(sock);
2328 if (ret) {
2329 PERROR("close");
2330 }
2331 sock = -1;
2332 clean_command_ctx(&cmd_ctx);
2333 continue;
2334 }
2335
2336 health_code_update();
2337
2338 // TODO: Validate cmd_ctx including sanity check for
2339 // security purpose.
2340
2341 rcu_thread_online();
2342 /*
2343 * This function dispatch the work to the kernel or userspace tracer
2344 * libs and fill the lttcomm_lttng_msg data structure of all the needed
2345 * informations for the client. The command context struct contains
2346 * everything this function may needs.
2347 */
2348 ret = process_client_msg(cmd_ctx, &sock, &sock_error);
2349 rcu_thread_offline();
2350 if (ret < 0) {
2351 if (sock >= 0) {
2352 ret = close(sock);
2353 if (ret) {
2354 PERROR("close");
2355 }
2356 }
2357 sock = -1;
2358 /*
2359 * TODO: Inform client somehow of the fatal error. At
2360 * this point, ret < 0 means that a zmalloc failed
2361 * (ENOMEM). Error detected but still accept
2362 * command, unless a socket error has been
2363 * detected.
2364 */
2365 clean_command_ctx(&cmd_ctx);
2366 continue;
2367 }
2368
2369 cmd_completion_handler = cmd_pop_completion_handler();
2370 if (cmd_completion_handler) {
2371 enum lttng_error_code completion_code;
2372
2373 completion_code = cmd_completion_handler->run(
2374 cmd_completion_handler->data);
2375 if (completion_code != LTTNG_OK) {
2376 clean_command_ctx(&cmd_ctx);
2377 continue;
2378 }
2379 }
2380
2381 health_code_update();
2382
2383 if (sock >= 0) {
2384 DBG("Sending response (size: %d, retcode: %s (%d))",
2385 cmd_ctx->lttng_msg_size,
2386 lttng_strerror(-cmd_ctx->llm->ret_code),
2387 cmd_ctx->llm->ret_code);
2388 ret = send_unix_sock(sock, cmd_ctx->llm,
2389 cmd_ctx->lttng_msg_size);
2390 if (ret < 0) {
2391 ERR("Failed to send data back to client");
2392 }
2393
2394 /* End of transmission */
2395 ret = close(sock);
2396 if (ret) {
2397 PERROR("close");
2398 }
2399 }
2400 sock = -1;
2401
2402 clean_command_ctx(&cmd_ctx);
2403
2404 health_code_update();
2405 }
2406
2407 exit:
2408 error:
2409 if (sock >= 0) {
2410 ret = close(sock);
2411 if (ret) {
2412 PERROR("close");
2413 }
2414 }
2415
2416 lttng_poll_clean(&events);
2417 clean_command_ctx(&cmd_ctx);
2418
2419 error_listen:
2420 error_create_poll:
2421 unlink(config.client_unix_sock_path.value);
2422 ret = close(client_sock);
2423 if (ret) {
2424 PERROR("close");
2425 }
2426
2427 if (err) {
2428 health_error();
2429 ERR("Health error occurred in %s", __func__);
2430 }
2431
2432 health_unregister(health_sessiond);
2433
2434 DBG("Client thread dying");
2435
2436 rcu_unregister_thread();
2437 return NULL;
2438 }
2439
2440 static
2441 bool shutdown_client_thread(void *thread_data)
2442 {
2443 struct lttng_pipe *client_quit_pipe = thread_data;
2444 const int write_fd = lttng_pipe_get_writefd(client_quit_pipe);
2445
2446 return notify_thread_pipe(write_fd) == 1;
2447 }
2448
2449 struct lttng_thread *launch_client_thread(void)
2450 {
2451 bool thread_running;
2452 struct lttng_pipe *client_quit_pipe;
2453 struct lttng_thread *thread = NULL;
2454 int client_sock_fd = -1;
2455
2456 sem_init(&thread_state.ready, 0, 0);
2457 client_quit_pipe = lttng_pipe_open(FD_CLOEXEC);
2458 if (!client_quit_pipe) {
2459 goto error;
2460 }
2461
2462 client_sock_fd = create_client_sock();
2463 if (client_sock_fd < 0) {
2464 goto error;
2465 }
2466
2467 thread_state.client_sock = client_sock_fd;
2468 thread = lttng_thread_create("Client management",
2469 thread_manage_clients,
2470 shutdown_client_thread,
2471 cleanup_client_thread,
2472 client_quit_pipe);
2473 if (!thread) {
2474 goto error;
2475 }
2476 /* The client thread now owns the client sock fd and the quit pipe. */
2477 client_sock_fd = -1;
2478 client_quit_pipe = NULL;
2479
2480 /*
2481 * This thread is part of the threads that need to be fully
2482 * initialized before the session daemon is marked as "ready".
2483 */
2484 thread_running = wait_thread_status();
2485 if (!thread_running) {
2486 goto error;
2487 }
2488 return thread;
2489 error:
2490 if (client_sock_fd >= 0) {
2491 if (close(client_sock_fd)) {
2492 PERROR("Failed to close client socket");
2493 }
2494 }
2495 lttng_thread_put(thread);
2496 cleanup_client_thread(client_quit_pipe);
2497 return NULL;
2498 }
LTTng tools - Deliverables
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