trackers: add sessiond tracker list implementation
[lttng-tools.git] / src / bin / lttng-sessiond / client.c
CommitLineData
917a718d
JG
1/*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 * 2013 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License, version 2 only,
8 * as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18 */
19
20#include <stddef.h>
21#include <pthread.h>
22#include <signal.h>
23#include <sys/stat.h>
24#include <common/compat/getenv.h>
25#include <common/unix.h>
26#include <common/utils.h>
27#include <lttng/userspace-probe-internal.h>
28#include <lttng/event-internal.h>
b178f53e
JG
29#include <lttng/session-internal.h>
30#include <lttng/session-descriptor-internal.h>
917a718d
JG
31
32#include "client.h"
33#include "lttng-sessiond.h"
34#include "cmd.h"
35#include "kernel.h"
36#include "save.h"
37#include "health-sessiond.h"
38#include "testpoint.h"
39#include "utils.h"
4ec029ed 40#include "manage-consumer.h"
022349df 41#include "clear.h"
917a718d
JG
42
43static bool is_root;
44
45static struct thread_state {
6cb45e93
JG
46 sem_t ready;
47 bool running;
0f68efb6 48 int client_sock;
6cb45e93
JG
49} thread_state;
50
51static void set_thread_status(bool running)
917a718d 52{
6cb45e93
JG
53 DBG("Marking client thread's state as %s", running ? "running" : "error");
54 thread_state.running = running;
55 sem_post(&thread_state.ready);
917a718d
JG
56}
57
6cb45e93 58static bool wait_thread_status(void)
917a718d 59{
6cb45e93
JG
60 DBG("Waiting for client thread to be ready");
61 sem_wait(&thread_state.ready);
62 if (thread_state.running) {
63 DBG("Client thread is ready");
64 } else {
65 ERR("Initialization of client thread failed");
917a718d 66 }
6cb45e93
JG
67
68 return thread_state.running;
917a718d
JG
69}
70
71/*
72 * Setup the outgoing data buffer for the response (llm) by allocating the
73 * right amount of memory and copying the original information from the lsm
74 * structure.
75 *
76 * Return 0 on success, negative value on error.
77 */
78static int setup_lttng_msg(struct command_ctx *cmd_ctx,
79 const void *payload_buf, size_t payload_len,
80 const void *cmd_header_buf, size_t cmd_header_len)
81{
82 int ret = 0;
83 const size_t header_len = sizeof(struct lttcomm_lttng_msg);
84 const size_t cmd_header_offset = header_len;
85 const size_t payload_offset = cmd_header_offset + cmd_header_len;
86 const size_t total_msg_size = header_len + cmd_header_len + payload_len;
87
99a98ed3 88 free(cmd_ctx->llm);
917a718d
JG
89 cmd_ctx->llm = zmalloc(total_msg_size);
90
91 if (cmd_ctx->llm == NULL) {
92 PERROR("zmalloc");
93 ret = -ENOMEM;
94 goto end;
95 }
96
97 /* Copy common data */
98 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
99 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
100 cmd_ctx->llm->cmd_header_size = cmd_header_len;
101 cmd_ctx->llm->data_size = payload_len;
102 cmd_ctx->lttng_msg_size = total_msg_size;
103
104 /* Copy command header */
105 if (cmd_header_len) {
106 memcpy(((uint8_t *) cmd_ctx->llm) + cmd_header_offset, cmd_header_buf,
107 cmd_header_len);
108 }
109
110 /* Copy payload */
111 if (payload_len) {
112 memcpy(((uint8_t *) cmd_ctx->llm) + payload_offset, payload_buf,
113 payload_len);
114 }
115
116end:
117 return ret;
118}
119
120/*
121 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
4ec029ed 122 * exec or it will fail.
917a718d
JG
123 */
124static int spawn_consumer_thread(struct consumer_data *consumer_data)
125{
4ec029ed 126 return launch_consumer_management_thread(consumer_data) ? 0 : -1;
917a718d
JG
127}
128
129/*
130 * Fork and exec a consumer daemon (consumerd).
131 *
132 * Return pid if successful else -1.
133 */
134static pid_t spawn_consumerd(struct consumer_data *consumer_data)
135{
136 int ret;
137 pid_t pid;
138 const char *consumer_to_use;
139 const char *verbosity;
140 struct stat st;
141
142 DBG("Spawning consumerd");
143
144 pid = fork();
145 if (pid == 0) {
146 /*
147 * Exec consumerd.
148 */
149 if (config.verbose_consumer) {
150 verbosity = "--verbose";
151 } else if (lttng_opt_quiet) {
152 verbosity = "--quiet";
153 } else {
154 verbosity = "";
155 }
156
157 switch (consumer_data->type) {
158 case LTTNG_CONSUMER_KERNEL:
159 /*
160 * Find out which consumerd to execute. We will first try the
161 * 64-bit path, then the sessiond's installation directory, and
162 * fallback on the 32-bit one,
163 */
164 DBG3("Looking for a kernel consumer at these locations:");
165 DBG3(" 1) %s", config.consumerd64_bin_path.value ? : "NULL");
166 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, DEFAULT_CONSUMERD_FILE);
167 DBG3(" 3) %s", config.consumerd32_bin_path.value ? : "NULL");
168 if (stat(config.consumerd64_bin_path.value, &st) == 0) {
169 DBG3("Found location #1");
170 consumer_to_use = config.consumerd64_bin_path.value;
171 } else if (stat(INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE, &st) == 0) {
172 DBG3("Found location #2");
173 consumer_to_use = INSTALL_BIN_PATH "/" DEFAULT_CONSUMERD_FILE;
174 } else if (config.consumerd32_bin_path.value &&
175 stat(config.consumerd32_bin_path.value, &st) == 0) {
176 DBG3("Found location #3");
177 consumer_to_use = config.consumerd32_bin_path.value;
178 } else {
179 DBG("Could not find any valid consumerd executable");
180 ret = -EINVAL;
181 goto error;
182 }
183 DBG("Using kernel consumer at: %s", consumer_to_use);
184 (void) execl(consumer_to_use,
185 "lttng-consumerd", verbosity, "-k",
186 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
187 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
188 "--group", config.tracing_group_name.value,
189 NULL);
190 break;
191 case LTTNG_CONSUMER64_UST:
192 {
193 if (config.consumerd64_lib_dir.value) {
194 char *tmp;
195 size_t tmplen;
196 char *tmpnew;
197
198 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
199 if (!tmp) {
200 tmp = "";
201 }
202 tmplen = strlen(config.consumerd64_lib_dir.value) + 1 /* : */ + strlen(tmp);
203 tmpnew = zmalloc(tmplen + 1 /* \0 */);
204 if (!tmpnew) {
205 ret = -ENOMEM;
206 goto error;
207 }
208 strcat(tmpnew, config.consumerd64_lib_dir.value);
209 if (tmp[0] != '\0') {
210 strcat(tmpnew, ":");
211 strcat(tmpnew, tmp);
212 }
213 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
214 free(tmpnew);
215 if (ret) {
216 ret = -errno;
217 goto error;
218 }
219 }
220 DBG("Using 64-bit UST consumer at: %s", config.consumerd64_bin_path.value);
221 (void) execl(config.consumerd64_bin_path.value, "lttng-consumerd", verbosity, "-u",
222 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
223 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
224 "--group", config.tracing_group_name.value,
225 NULL);
226 break;
227 }
228 case LTTNG_CONSUMER32_UST:
229 {
230 if (config.consumerd32_lib_dir.value) {
231 char *tmp;
232 size_t tmplen;
233 char *tmpnew;
234
235 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
236 if (!tmp) {
237 tmp = "";
238 }
239 tmplen = strlen(config.consumerd32_lib_dir.value) + 1 /* : */ + strlen(tmp);
240 tmpnew = zmalloc(tmplen + 1 /* \0 */);
241 if (!tmpnew) {
242 ret = -ENOMEM;
243 goto error;
244 }
245 strcat(tmpnew, config.consumerd32_lib_dir.value);
246 if (tmp[0] != '\0') {
247 strcat(tmpnew, ":");
248 strcat(tmpnew, tmp);
249 }
250 ret = setenv("LD_LIBRARY_PATH", tmpnew, 1);
251 free(tmpnew);
252 if (ret) {
253 ret = -errno;
254 goto error;
255 }
256 }
257 DBG("Using 32-bit UST consumer at: %s", config.consumerd32_bin_path.value);
258 (void) execl(config.consumerd32_bin_path.value, "lttng-consumerd", verbosity, "-u",
259 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
260 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
261 "--group", config.tracing_group_name.value,
262 NULL);
263 break;
264 }
265 default:
266 ERR("unknown consumer type");
267 errno = 0;
268 }
269 if (errno != 0) {
270 PERROR("Consumer execl()");
271 }
272 /* Reaching this point, we got a failure on our execl(). */
273 exit(EXIT_FAILURE);
274 } else if (pid > 0) {
275 ret = pid;
276 } else {
277 PERROR("start consumer fork");
278 ret = -errno;
279 }
280error:
281 return ret;
282}
283
284/*
285 * Spawn the consumerd daemon and session daemon thread.
286 */
287static int start_consumerd(struct consumer_data *consumer_data)
288{
289 int ret;
290
291 /*
292 * Set the listen() state on the socket since there is a possible race
293 * between the exec() of the consumer daemon and this call if place in the
294 * consumer thread. See bug #366 for more details.
295 */
296 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
297 if (ret < 0) {
298 goto error;
299 }
300
301 pthread_mutex_lock(&consumer_data->pid_mutex);
302 if (consumer_data->pid != 0) {
303 pthread_mutex_unlock(&consumer_data->pid_mutex);
304 goto end;
305 }
306
307 ret = spawn_consumerd(consumer_data);
308 if (ret < 0) {
309 ERR("Spawning consumerd failed");
310 pthread_mutex_unlock(&consumer_data->pid_mutex);
311 goto error;
312 }
313
314 /* Setting up the consumer_data pid */
315 consumer_data->pid = ret;
316 DBG2("Consumer pid %d", consumer_data->pid);
317 pthread_mutex_unlock(&consumer_data->pid_mutex);
318
319 DBG2("Spawning consumer control thread");
320 ret = spawn_consumer_thread(consumer_data);
321 if (ret < 0) {
322 ERR("Fatal error spawning consumer control thread");
323 goto error;
324 }
325
326end:
327 return 0;
328
329error:
330 /* Cleanup already created sockets on error. */
331 if (consumer_data->err_sock >= 0) {
332 int err;
333
334 err = close(consumer_data->err_sock);
335 if (err < 0) {
336 PERROR("close consumer data error socket");
337 }
338 }
339 return ret;
340}
341
342/*
343 * Copy consumer output from the tracing session to the domain session. The
344 * function also applies the right modification on a per domain basis for the
345 * trace files destination directory.
346 *
347 * Should *NOT* be called with RCU read-side lock held.
348 */
349static int copy_session_consumer(int domain, struct ltt_session *session)
350{
351 int ret;
352 const char *dir_name;
353 struct consumer_output *consumer;
354
355 assert(session);
356 assert(session->consumer);
357
358 switch (domain) {
359 case LTTNG_DOMAIN_KERNEL:
360 DBG3("Copying tracing session consumer output in kernel session");
361 /*
362 * XXX: We should audit the session creation and what this function
363 * does "extra" in order to avoid a destroy since this function is used
364 * in the domain session creation (kernel and ust) only. Same for UST
365 * domain.
366 */
367 if (session->kernel_session->consumer) {
368 consumer_output_put(session->kernel_session->consumer);
369 }
370 session->kernel_session->consumer =
371 consumer_copy_output(session->consumer);
372 /* Ease our life a bit for the next part */
373 consumer = session->kernel_session->consumer;
374 dir_name = DEFAULT_KERNEL_TRACE_DIR;
375 break;
376 case LTTNG_DOMAIN_JUL:
377 case LTTNG_DOMAIN_LOG4J:
378 case LTTNG_DOMAIN_PYTHON:
379 case LTTNG_DOMAIN_UST:
380 DBG3("Copying tracing session consumer output in UST session");
381 if (session->ust_session->consumer) {
382 consumer_output_put(session->ust_session->consumer);
383 }
384 session->ust_session->consumer =
385 consumer_copy_output(session->consumer);
386 /* Ease our life a bit for the next part */
387 consumer = session->ust_session->consumer;
388 dir_name = DEFAULT_UST_TRACE_DIR;
389 break;
390 default:
391 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
392 goto error;
393 }
394
395 /* Append correct directory to subdir */
b178f53e
JG
396 ret = lttng_strncpy(consumer->domain_subdir, dir_name,
397 sizeof(consumer->domain_subdir));
398 if (ret) {
399 ret = LTTNG_ERR_UNK;
400 goto error;
401 }
402 DBG3("Copy session consumer subdir %s", consumer->domain_subdir);
917a718d
JG
403 ret = LTTNG_OK;
404
405error:
406 return ret;
407}
408
409/*
410 * Create an UST session and add it to the session ust list.
411 *
412 * Should *NOT* be called with RCU read-side lock held.
413 */
414static int create_ust_session(struct ltt_session *session,
df4f5a87 415 const struct lttng_domain *domain)
917a718d
JG
416{
417 int ret;
418 struct ltt_ust_session *lus = NULL;
419
420 assert(session);
421 assert(domain);
422 assert(session->consumer);
423
424 switch (domain->type) {
425 case LTTNG_DOMAIN_JUL:
426 case LTTNG_DOMAIN_LOG4J:
427 case LTTNG_DOMAIN_PYTHON:
428 case LTTNG_DOMAIN_UST:
429 break;
430 default:
431 ERR("Unknown UST domain on create session %d", domain->type);
432 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
433 goto error;
434 }
435
436 DBG("Creating UST session");
437
438 lus = trace_ust_create_session(session->id);
439 if (lus == NULL) {
440 ret = LTTNG_ERR_UST_SESS_FAIL;
441 goto error;
442 }
443
444 lus->uid = session->uid;
445 lus->gid = session->gid;
446 lus->output_traces = session->output_traces;
447 lus->snapshot_mode = session->snapshot_mode;
448 lus->live_timer_interval = session->live_timer;
449 session->ust_session = lus;
450 if (session->shm_path[0]) {
451 strncpy(lus->root_shm_path, session->shm_path,
452 sizeof(lus->root_shm_path));
453 lus->root_shm_path[sizeof(lus->root_shm_path) - 1] = '\0';
454 strncpy(lus->shm_path, session->shm_path,
455 sizeof(lus->shm_path));
456 lus->shm_path[sizeof(lus->shm_path) - 1] = '\0';
457 strncat(lus->shm_path, "/ust",
458 sizeof(lus->shm_path) - strlen(lus->shm_path) - 1);
459 }
460 /* Copy session output to the newly created UST session */
461 ret = copy_session_consumer(domain->type, session);
462 if (ret != LTTNG_OK) {
463 goto error;
464 }
465
466 return LTTNG_OK;
467
468error:
469 free(lus);
470 session->ust_session = NULL;
471 return ret;
472}
473
474/*
475 * Create a kernel tracer session then create the default channel.
476 */
477static int create_kernel_session(struct ltt_session *session)
478{
479 int ret;
480
481 DBG("Creating kernel session");
482
7d268848 483 ret = kernel_create_session(session);
917a718d
JG
484 if (ret < 0) {
485 ret = LTTNG_ERR_KERN_SESS_FAIL;
5d0a7bcb 486 goto error_create;
917a718d
JG
487 }
488
489 /* Code flow safety */
490 assert(session->kernel_session);
491
492 /* Copy session output to the newly created Kernel session */
493 ret = copy_session_consumer(LTTNG_DOMAIN_KERNEL, session);
494 if (ret != LTTNG_OK) {
495 goto error;
496 }
497
498 session->kernel_session->uid = session->uid;
499 session->kernel_session->gid = session->gid;
500 session->kernel_session->output_traces = session->output_traces;
501 session->kernel_session->snapshot_mode = session->snapshot_mode;
502
503 return LTTNG_OK;
504
505error:
506 trace_kernel_destroy_session(session->kernel_session);
507 session->kernel_session = NULL;
5d0a7bcb 508error_create:
917a718d
JG
509 return ret;
510}
511
512/*
513 * Count number of session permitted by uid/gid.
514 */
515static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
516{
517 unsigned int i = 0;
518 struct ltt_session *session;
519 const struct ltt_session_list *session_list = session_get_list();
520
521 DBG("Counting number of available session for UID %d GID %d",
522 uid, gid);
523 cds_list_for_each_entry(session, &session_list->head, list) {
524 if (!session_get(session)) {
525 continue;
526 }
527 session_lock(session);
528 /* Only count the sessions the user can control. */
529 if (session_access_ok(session, uid, gid) &&
530 !session->destroyed) {
531 i++;
532 }
533 session_unlock(session);
534 session_put(session);
535 }
536 return i;
537}
538
539static int receive_userspace_probe(struct command_ctx *cmd_ctx, int sock,
540 int *sock_error, struct lttng_event *event)
541{
542 int fd, ret;
543 struct lttng_userspace_probe_location *probe_location;
544 const struct lttng_userspace_probe_location_lookup_method *lookup = NULL;
545 struct lttng_dynamic_buffer probe_location_buffer;
546 struct lttng_buffer_view buffer_view;
547
548 /*
549 * Create a buffer to store the serialized version of the probe
550 * location.
551 */
552 lttng_dynamic_buffer_init(&probe_location_buffer);
553 ret = lttng_dynamic_buffer_set_size(&probe_location_buffer,
554 cmd_ctx->lsm->u.enable.userspace_probe_location_len);
555 if (ret) {
556 ret = LTTNG_ERR_NOMEM;
557 goto error;
558 }
559
560 /*
561 * Receive the probe location.
562 */
563 ret = lttcomm_recv_unix_sock(sock, probe_location_buffer.data,
564 probe_location_buffer.size);
565 if (ret <= 0) {
566 DBG("Nothing recv() from client var len data... continuing");
567 *sock_error = 1;
568 lttng_dynamic_buffer_reset(&probe_location_buffer);
569 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
570 goto error;
571 }
572
573 buffer_view = lttng_buffer_view_from_dynamic_buffer(
574 &probe_location_buffer, 0, probe_location_buffer.size);
575
576 /*
577 * Extract the probe location from the serialized version.
578 */
579 ret = lttng_userspace_probe_location_create_from_buffer(
580 &buffer_view, &probe_location);
581 if (ret < 0) {
582 WARN("Failed to create a userspace probe location from the received buffer");
583 lttng_dynamic_buffer_reset( &probe_location_buffer);
584 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
585 goto error;
586 }
587
588 /*
589 * Receive the file descriptor to the target binary from the client.
590 */
591 DBG("Receiving userspace probe target FD from client ...");
592 ret = lttcomm_recv_fds_unix_sock(sock, &fd, 1);
593 if (ret <= 0) {
594 DBG("Nothing recv() from client userspace probe fd... continuing");
595 *sock_error = 1;
596 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
597 goto error;
598 }
599
600 /*
601 * Set the file descriptor received from the client through the unix
602 * socket in the probe location.
603 */
604 lookup = lttng_userspace_probe_location_get_lookup_method(probe_location);
605 if (!lookup) {
606 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
607 goto error;
608 }
609
610 /*
611 * From the kernel tracer's perspective, all userspace probe event types
612 * are all the same: a file and an offset.
613 */
614 switch (lttng_userspace_probe_location_lookup_method_get_type(lookup)) {
615 case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF:
616 ret = lttng_userspace_probe_location_function_set_binary_fd(
617 probe_location, fd);
618 break;
619 case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT:
620 ret = lttng_userspace_probe_location_tracepoint_set_binary_fd(
621 probe_location, fd);
622 break;
623 default:
624 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
625 goto error;
626 }
627
628 if (ret) {
629 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
630 goto error;
631 }
632
633 /* Attach the probe location to the event. */
634 ret = lttng_event_set_userspace_probe_location(event, probe_location);
635 if (ret) {
636 ret = LTTNG_ERR_PROBE_LOCATION_INVAL;
637 goto error;
638 }
639
640 lttng_dynamic_buffer_reset(&probe_location_buffer);
641error:
642 return ret;
643}
644
917a718d
JG
645/*
646 * Version of setup_lttng_msg() without command header.
647 */
648static int setup_lttng_msg_no_cmd_header(struct command_ctx *cmd_ctx,
649 void *payload_buf, size_t payload_len)
650{
651 return setup_lttng_msg(cmd_ctx, payload_buf, payload_len, NULL, 0);
652}
653
654/*
655 * Free memory of a command context structure.
656 */
657static void clean_command_ctx(struct command_ctx **cmd_ctx)
658{
659 DBG("Clean command context structure");
660 if (*cmd_ctx) {
661 if ((*cmd_ctx)->llm) {
662 free((*cmd_ctx)->llm);
663 }
664 if ((*cmd_ctx)->lsm) {
665 free((*cmd_ctx)->lsm);
666 }
667 free(*cmd_ctx);
668 *cmd_ctx = NULL;
669 }
670}
671
672/*
673 * Check if the current kernel tracer supports the session rotation feature.
674 * Return 1 if it does, 0 otherwise.
675 */
676static int check_rotate_compatible(void)
677{
678 int ret = 1;
679
680 if (kernel_tracer_version.major != 2 || kernel_tracer_version.minor < 11) {
681 DBG("Kernel tracer version is not compatible with the rotation feature");
682 ret = 0;
683 }
684
685 return ret;
686}
687
688/*
689 * Send data on a unix socket using the liblttsessiondcomm API.
690 *
691 * Return lttcomm error code.
692 */
693static int send_unix_sock(int sock, void *buf, size_t len)
694{
695 /* Check valid length */
696 if (len == 0) {
697 return -1;
698 }
699
700 return lttcomm_send_unix_sock(sock, buf, len);
701}
702
703/*
704 * Process the command requested by the lttng client within the command
705 * context structure. This function make sure that the return structure (llm)
706 * is set and ready for transmission before returning.
707 *
708 * Return any error encountered or 0 for success.
709 *
710 * "sock" is only used for special-case var. len data.
3e3665b8
JG
711 * A command may assume the ownership of the socket, in which case its value
712 * should be set to -1.
917a718d
JG
713 *
714 * Should *NOT* be called with RCU read-side lock held.
715 */
3e3665b8 716static int process_client_msg(struct command_ctx *cmd_ctx, int *sock,
917a718d
JG
717 int *sock_error)
718{
719 int ret = LTTNG_OK;
720 int need_tracing_session = 1;
721 int need_domain;
722
723 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
724
725 assert(!rcu_read_ongoing());
726
727 *sock_error = 0;
728
729 switch (cmd_ctx->lsm->cmd_type) {
b178f53e 730 case LTTNG_CREATE_SESSION_EXT:
917a718d
JG
731 case LTTNG_DESTROY_SESSION:
732 case LTTNG_LIST_SESSIONS:
733 case LTTNG_LIST_DOMAINS:
734 case LTTNG_START_TRACE:
735 case LTTNG_STOP_TRACE:
736 case LTTNG_DATA_PENDING:
737 case LTTNG_SNAPSHOT_ADD_OUTPUT:
738 case LTTNG_SNAPSHOT_DEL_OUTPUT:
739 case LTTNG_SNAPSHOT_LIST_OUTPUT:
740 case LTTNG_SNAPSHOT_RECORD:
741 case LTTNG_SAVE_SESSION:
742 case LTTNG_SET_SESSION_SHM_PATH:
743 case LTTNG_REGENERATE_METADATA:
744 case LTTNG_REGENERATE_STATEDUMP:
745 case LTTNG_REGISTER_TRIGGER:
746 case LTTNG_UNREGISTER_TRIGGER:
747 case LTTNG_ROTATE_SESSION:
748 case LTTNG_ROTATION_GET_INFO:
749 case LTTNG_ROTATION_SET_SCHEDULE:
750 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
022349df 751 case LTTNG_CLEAR_SESSION:
917a718d
JG
752 need_domain = 0;
753 break;
754 default:
755 need_domain = 1;
756 }
757
758 if (config.no_kernel && need_domain
759 && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
760 if (!is_root) {
761 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
762 } else {
763 ret = LTTNG_ERR_KERN_NA;
764 }
765 goto error;
766 }
767
768 /* Deny register consumer if we already have a spawned consumer. */
769 if (cmd_ctx->lsm->cmd_type == LTTNG_REGISTER_CONSUMER) {
770 pthread_mutex_lock(&kconsumer_data.pid_mutex);
771 if (kconsumer_data.pid > 0) {
772 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
773 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
774 goto error;
775 }
776 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
777 }
778
779 /*
780 * Check for command that don't needs to allocate a returned payload. We do
781 * this here so we don't have to make the call for no payload at each
782 * command.
783 */
784 switch(cmd_ctx->lsm->cmd_type) {
785 case LTTNG_LIST_SESSIONS:
786 case LTTNG_LIST_TRACEPOINTS:
787 case LTTNG_LIST_TRACEPOINT_FIELDS:
788 case LTTNG_LIST_DOMAINS:
789 case LTTNG_LIST_CHANNELS:
790 case LTTNG_LIST_EVENTS:
791 case LTTNG_LIST_SYSCALLS:
792 case LTTNG_LIST_TRACKER_PIDS:
793 case LTTNG_DATA_PENDING:
794 case LTTNG_ROTATE_SESSION:
795 case LTTNG_ROTATION_GET_INFO:
796 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
797 break;
798 default:
799 /* Setup lttng message with no payload */
800 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0);
801 if (ret < 0) {
802 /* This label does not try to unlock the session */
803 goto init_setup_error;
804 }
805 }
806
807 /* Commands that DO NOT need a session. */
808 switch (cmd_ctx->lsm->cmd_type) {
b178f53e 809 case LTTNG_CREATE_SESSION_EXT:
917a718d
JG
810 case LTTNG_LIST_SESSIONS:
811 case LTTNG_LIST_TRACEPOINTS:
812 case LTTNG_LIST_SYSCALLS:
813 case LTTNG_LIST_TRACEPOINT_FIELDS:
814 case LTTNG_SAVE_SESSION:
815 case LTTNG_REGISTER_TRIGGER:
816 case LTTNG_UNREGISTER_TRIGGER:
817 need_tracing_session = 0;
818 break;
819 default:
820 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
821 /*
822 * We keep the session list lock across _all_ commands
823 * for now, because the per-session lock does not
824 * handle teardown properly.
825 */
826 session_lock_list();
827 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
828 if (cmd_ctx->session == NULL) {
829 ret = LTTNG_ERR_SESS_NOT_FOUND;
830 goto error;
831 } else {
832 /* Acquire lock for the session */
833 session_lock(cmd_ctx->session);
834 }
835 break;
836 }
837
838 /*
839 * Commands that need a valid session but should NOT create one if none
840 * exists. Instead of creating one and destroying it when the command is
841 * handled, process that right before so we save some round trip in useless
842 * code path.
843 */
844 switch (cmd_ctx->lsm->cmd_type) {
845 case LTTNG_DISABLE_CHANNEL:
846 case LTTNG_DISABLE_EVENT:
847 switch (cmd_ctx->lsm->domain.type) {
848 case LTTNG_DOMAIN_KERNEL:
849 if (!cmd_ctx->session->kernel_session) {
850 ret = LTTNG_ERR_NO_CHANNEL;
851 goto error;
852 }
853 break;
854 case LTTNG_DOMAIN_JUL:
855 case LTTNG_DOMAIN_LOG4J:
856 case LTTNG_DOMAIN_PYTHON:
857 case LTTNG_DOMAIN_UST:
858 if (!cmd_ctx->session->ust_session) {
859 ret = LTTNG_ERR_NO_CHANNEL;
860 goto error;
861 }
862 break;
863 default:
864 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
865 goto error;
866 }
867 default:
868 break;
869 }
870
871 if (!need_domain) {
872 goto skip_domain;
873 }
874
875 /*
876 * Check domain type for specific "pre-action".
877 */
878 switch (cmd_ctx->lsm->domain.type) {
879 case LTTNG_DOMAIN_KERNEL:
880 if (!is_root) {
881 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
882 goto error;
883 }
884
7d268848
MD
885 /* Kernel tracer check */
886 if (!kernel_tracer_is_initialized()) {
887 /* Basically, load kernel tracer modules */
888 ret = init_kernel_tracer();
889 if (ret != 0) {
890 goto error;
891 }
892 }
893
917a718d
JG
894 /* Consumer is in an ERROR state. Report back to client */
895 if (uatomic_read(&kernel_consumerd_state) == CONSUMER_ERROR) {
896 ret = LTTNG_ERR_NO_KERNCONSUMERD;
897 goto error;
898 }
899
900 /* Need a session for kernel command */
901 if (need_tracing_session) {
902 if (cmd_ctx->session->kernel_session == NULL) {
903 ret = create_kernel_session(cmd_ctx->session);
51630bd8 904 if (ret != LTTNG_OK) {
917a718d
JG
905 ret = LTTNG_ERR_KERN_SESS_FAIL;
906 goto error;
907 }
908 }
909
910 /* Start the kernel consumer daemon */
911 pthread_mutex_lock(&kconsumer_data.pid_mutex);
912 if (kconsumer_data.pid == 0 &&
913 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
914 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
915 ret = start_consumerd(&kconsumer_data);
916 if (ret < 0) {
917 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
918 goto error;
919 }
920 uatomic_set(&kernel_consumerd_state, CONSUMER_STARTED);
921 } else {
922 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
923 }
924
925 /*
926 * The consumer was just spawned so we need to add the socket to
927 * the consumer output of the session if exist.
928 */
929 ret = consumer_create_socket(&kconsumer_data,
930 cmd_ctx->session->kernel_session->consumer);
931 if (ret < 0) {
932 goto error;
933 }
934 }
935
936 break;
937 case LTTNG_DOMAIN_JUL:
938 case LTTNG_DOMAIN_LOG4J:
939 case LTTNG_DOMAIN_PYTHON:
940 case LTTNG_DOMAIN_UST:
941 {
942 if (!ust_app_supported()) {
943 ret = LTTNG_ERR_NO_UST;
944 goto error;
945 }
946 /* Consumer is in an ERROR state. Report back to client */
947 if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) {
948 ret = LTTNG_ERR_NO_USTCONSUMERD;
949 goto error;
950 }
951
952 if (need_tracing_session) {
953 /* Create UST session if none exist. */
954 if (cmd_ctx->session->ust_session == NULL) {
955 ret = create_ust_session(cmd_ctx->session,
df4f5a87 956 ALIGNED_CONST_PTR(cmd_ctx->lsm->domain));
917a718d
JG
957 if (ret != LTTNG_OK) {
958 goto error;
959 }
960 }
961
962 /* Start the UST consumer daemons */
963 /* 64-bit */
964 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
965 if (config.consumerd64_bin_path.value &&
966 ustconsumer64_data.pid == 0 &&
967 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
968 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
969 ret = start_consumerd(&ustconsumer64_data);
970 if (ret < 0) {
971 ret = LTTNG_ERR_UST_CONSUMER64_FAIL;
972 uatomic_set(&ust_consumerd64_fd, -EINVAL);
973 goto error;
974 }
975
976 uatomic_set(&ust_consumerd64_fd, ustconsumer64_data.cmd_sock);
977 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
978 } else {
979 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
980 }
981
982 /*
983 * Setup socket for consumer 64 bit. No need for atomic access
984 * since it was set above and can ONLY be set in this thread.
985 */
986 ret = consumer_create_socket(&ustconsumer64_data,
987 cmd_ctx->session->ust_session->consumer);
988 if (ret < 0) {
989 goto error;
990 }
991
992 /* 32-bit */
993 pthread_mutex_lock(&ustconsumer32_data.pid_mutex);
994 if (config.consumerd32_bin_path.value &&
995 ustconsumer32_data.pid == 0 &&
996 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
997 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
998 ret = start_consumerd(&ustconsumer32_data);
999 if (ret < 0) {
1000 ret = LTTNG_ERR_UST_CONSUMER32_FAIL;
1001 uatomic_set(&ust_consumerd32_fd, -EINVAL);
1002 goto error;
1003 }
1004
1005 uatomic_set(&ust_consumerd32_fd, ustconsumer32_data.cmd_sock);
1006 uatomic_set(&ust_consumerd_state, CONSUMER_STARTED);
1007 } else {
1008 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
1009 }
1010
1011 /*
1012 * Setup socket for consumer 32 bit. No need for atomic access
1013 * since it was set above and can ONLY be set in this thread.
1014 */
1015 ret = consumer_create_socket(&ustconsumer32_data,
1016 cmd_ctx->session->ust_session->consumer);
1017 if (ret < 0) {
1018 goto error;
1019 }
1020 }
1021 break;
1022 }
1023 default:
1024 break;
1025 }
1026skip_domain:
1027
1028 /* Validate consumer daemon state when start/stop trace command */
1029 if (cmd_ctx->lsm->cmd_type == LTTNG_START_TRACE ||
1030 cmd_ctx->lsm->cmd_type == LTTNG_STOP_TRACE) {
1031 switch (cmd_ctx->lsm->domain.type) {
1032 case LTTNG_DOMAIN_NONE:
1033 break;
1034 case LTTNG_DOMAIN_JUL:
1035 case LTTNG_DOMAIN_LOG4J:
1036 case LTTNG_DOMAIN_PYTHON:
1037 case LTTNG_DOMAIN_UST:
1038 if (uatomic_read(&ust_consumerd_state) != CONSUMER_STARTED) {
1039 ret = LTTNG_ERR_NO_USTCONSUMERD;
1040 goto error;
1041 }
1042 break;
1043 case LTTNG_DOMAIN_KERNEL:
1044 if (uatomic_read(&kernel_consumerd_state) != CONSUMER_STARTED) {
1045 ret = LTTNG_ERR_NO_KERNCONSUMERD;
1046 goto error;
1047 }
1048 break;
1049 default:
1050 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
1051 goto error;
1052 }
1053 }
1054
1055 /*
1056 * Check that the UID or GID match that of the tracing session.
1057 * The root user can interact with all sessions.
1058 */
1059 if (need_tracing_session) {
1060 if (!session_access_ok(cmd_ctx->session,
1061 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1062 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds)) ||
1063 cmd_ctx->session->destroyed) {
1064 ret = LTTNG_ERR_EPERM;
1065 goto error;
1066 }
1067 }
1068
1069 /*
1070 * Send relayd information to consumer as soon as we have a domain and a
1071 * session defined.
1072 */
1073 if (cmd_ctx->session && need_domain) {
1074 /*
1075 * Setup relayd if not done yet. If the relayd information was already
1076 * sent to the consumer, this call will gracefully return.
1077 */
1078 ret = cmd_setup_relayd(cmd_ctx->session);
1079 if (ret != LTTNG_OK) {
1080 goto error;
1081 }
1082 }
1083
1084 /* Process by command type */
1085 switch (cmd_ctx->lsm->cmd_type) {
1086 case LTTNG_ADD_CONTEXT:
1087 {
1088 /*
1089 * An LTTNG_ADD_CONTEXT command might have a supplementary
1090 * payload if the context being added is an application context.
1091 */
1092 if (cmd_ctx->lsm->u.context.ctx.ctx ==
1093 LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
1094 char *provider_name = NULL, *context_name = NULL;
1095 size_t provider_name_len =
1096 cmd_ctx->lsm->u.context.provider_name_len;
1097 size_t context_name_len =
1098 cmd_ctx->lsm->u.context.context_name_len;
1099
1100 if (provider_name_len == 0 || context_name_len == 0) {
1101 /*
1102 * Application provider and context names MUST
1103 * be provided.
1104 */
1105 ret = -LTTNG_ERR_INVALID;
1106 goto error;
1107 }
1108
1109 provider_name = zmalloc(provider_name_len + 1);
1110 if (!provider_name) {
1111 ret = -LTTNG_ERR_NOMEM;
1112 goto error;
1113 }
1114 cmd_ctx->lsm->u.context.ctx.u.app_ctx.provider_name =
1115 provider_name;
1116
1117 context_name = zmalloc(context_name_len + 1);
1118 if (!context_name) {
1119 ret = -LTTNG_ERR_NOMEM;
1120 goto error_add_context;
1121 }
1122 cmd_ctx->lsm->u.context.ctx.u.app_ctx.ctx_name =
1123 context_name;
1124
3e3665b8 1125 ret = lttcomm_recv_unix_sock(*sock, provider_name,
917a718d
JG
1126 provider_name_len);
1127 if (ret < 0) {
1128 goto error_add_context;
1129 }
1130
3e3665b8 1131 ret = lttcomm_recv_unix_sock(*sock, context_name,
917a718d
JG
1132 context_name_len);
1133 if (ret < 0) {
1134 goto error_add_context;
1135 }
1136 }
1137
1138 /*
1139 * cmd_add_context assumes ownership of the provider and context
1140 * names.
1141 */
1142 ret = cmd_add_context(cmd_ctx->session,
1143 cmd_ctx->lsm->domain.type,
1144 cmd_ctx->lsm->u.context.channel_name,
df4f5a87 1145 ALIGNED_CONST_PTR(cmd_ctx->lsm->u.context.ctx),
917a718d
JG
1146 kernel_poll_pipe[1]);
1147
1148 cmd_ctx->lsm->u.context.ctx.u.app_ctx.provider_name = NULL;
1149 cmd_ctx->lsm->u.context.ctx.u.app_ctx.ctx_name = NULL;
1150error_add_context:
1151 free(cmd_ctx->lsm->u.context.ctx.u.app_ctx.provider_name);
1152 free(cmd_ctx->lsm->u.context.ctx.u.app_ctx.ctx_name);
1153 if (ret < 0) {
1154 goto error;
1155 }
1156 break;
1157 }
1158 case LTTNG_DISABLE_CHANNEL:
1159 {
1160 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
1161 cmd_ctx->lsm->u.disable.channel_name);
1162 break;
1163 }
1164 case LTTNG_DISABLE_EVENT:
1165 {
1166
1167 /*
1168 * FIXME: handle filter; for now we just receive the filter's
1169 * bytecode along with the filter expression which are sent by
1170 * liblttng-ctl and discard them.
1171 *
1172 * This fixes an issue where the client may block while sending
1173 * the filter payload and encounter an error because the session
1174 * daemon closes the socket without ever handling this data.
1175 */
1176 size_t count = cmd_ctx->lsm->u.disable.expression_len +
1177 cmd_ctx->lsm->u.disable.bytecode_len;
1178
1179 if (count) {
1180 char data[LTTNG_FILTER_MAX_LEN];
1181
1182 DBG("Discarding disable event command payload of size %zu", count);
1183 while (count) {
3e3665b8 1184 ret = lttcomm_recv_unix_sock(*sock, data,
917a718d
JG
1185 count > sizeof(data) ? sizeof(data) : count);
1186 if (ret < 0) {
1187 goto error;
1188 }
1189
1190 count -= (size_t) ret;
1191 }
1192 }
917a718d
JG
1193 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
1194 cmd_ctx->lsm->u.disable.channel_name,
df4f5a87 1195 ALIGNED_CONST_PTR(cmd_ctx->lsm->u.disable.event));
917a718d
JG
1196 break;
1197 }
1198 case LTTNG_ENABLE_CHANNEL:
1199 {
1200 cmd_ctx->lsm->u.channel.chan.attr.extended.ptr =
1201 (struct lttng_channel_extended *) &cmd_ctx->lsm->u.channel.extended;
df4f5a87
JG
1202 ret = cmd_enable_channel(cmd_ctx->session,
1203 ALIGNED_CONST_PTR(cmd_ctx->lsm->domain),
1204 ALIGNED_CONST_PTR(cmd_ctx->lsm->u.channel.chan),
917a718d
JG
1205 kernel_poll_pipe[1]);
1206 break;
1207 }
1208 case LTTNG_TRACK_PID:
1209 {
1210 ret = cmd_track_pid(cmd_ctx->session,
1211 cmd_ctx->lsm->domain.type,
1212 cmd_ctx->lsm->u.pid_tracker.pid);
1213 break;
1214 }
1215 case LTTNG_UNTRACK_PID:
1216 {
1217 ret = cmd_untrack_pid(cmd_ctx->session,
1218 cmd_ctx->lsm->domain.type,
1219 cmd_ctx->lsm->u.pid_tracker.pid);
1220 break;
1221 }
1222 case LTTNG_ENABLE_EVENT:
1223 {
1224 struct lttng_event *ev = NULL;
1225 struct lttng_event_exclusion *exclusion = NULL;
1226 struct lttng_filter_bytecode *bytecode = NULL;
1227 char *filter_expression = NULL;
1228
1229 /* Handle exclusion events and receive it from the client. */
1230 if (cmd_ctx->lsm->u.enable.exclusion_count > 0) {
1231 size_t count = cmd_ctx->lsm->u.enable.exclusion_count;
1232
1233 exclusion = zmalloc(sizeof(struct lttng_event_exclusion) +
1234 (count * LTTNG_SYMBOL_NAME_LEN));
1235 if (!exclusion) {
1236 ret = LTTNG_ERR_EXCLUSION_NOMEM;
1237 goto error;
1238 }
1239
1240 DBG("Receiving var len exclusion event list from client ...");
1241 exclusion->count = count;
3e3665b8 1242 ret = lttcomm_recv_unix_sock(*sock, exclusion->names,
917a718d
JG
1243 count * LTTNG_SYMBOL_NAME_LEN);
1244 if (ret <= 0) {
1245 DBG("Nothing recv() from client var len data... continuing");
1246 *sock_error = 1;
1247 free(exclusion);
1248 ret = LTTNG_ERR_EXCLUSION_INVAL;
1249 goto error;
1250 }
1251 }
1252
1253 /* Get filter expression from client. */
1254 if (cmd_ctx->lsm->u.enable.expression_len > 0) {
1255 size_t expression_len =
1256 cmd_ctx->lsm->u.enable.expression_len;
1257
1258 if (expression_len > LTTNG_FILTER_MAX_LEN) {
1259 ret = LTTNG_ERR_FILTER_INVAL;
1260 free(exclusion);
1261 goto error;
1262 }
1263
1264 filter_expression = zmalloc(expression_len);
1265 if (!filter_expression) {
1266 free(exclusion);
1267 ret = LTTNG_ERR_FILTER_NOMEM;
1268 goto error;
1269 }
1270
1271 /* Receive var. len. data */
1272 DBG("Receiving var len filter's expression from client ...");
3e3665b8 1273 ret = lttcomm_recv_unix_sock(*sock, filter_expression,
917a718d
JG
1274 expression_len);
1275 if (ret <= 0) {
1276 DBG("Nothing recv() from client var len data... continuing");
1277 *sock_error = 1;
1278 free(filter_expression);
1279 free(exclusion);
1280 ret = LTTNG_ERR_FILTER_INVAL;
1281 goto error;
1282 }
1283 }
1284
1285 /* Handle filter and get bytecode from client. */
1286 if (cmd_ctx->lsm->u.enable.bytecode_len > 0) {
1287 size_t bytecode_len = cmd_ctx->lsm->u.enable.bytecode_len;
1288
1289 if (bytecode_len > LTTNG_FILTER_MAX_LEN) {
1290 ret = LTTNG_ERR_FILTER_INVAL;
1291 free(filter_expression);
1292 free(exclusion);
1293 goto error;
1294 }
1295
1296 bytecode = zmalloc(bytecode_len);
1297 if (!bytecode) {
1298 free(filter_expression);
1299 free(exclusion);
1300 ret = LTTNG_ERR_FILTER_NOMEM;
1301 goto error;
1302 }
1303
1304 /* Receive var. len. data */
1305 DBG("Receiving var len filter's bytecode from client ...");
3e3665b8 1306 ret = lttcomm_recv_unix_sock(*sock, bytecode, bytecode_len);
917a718d
JG
1307 if (ret <= 0) {
1308 DBG("Nothing recv() from client var len data... continuing");
1309 *sock_error = 1;
1310 free(filter_expression);
1311 free(bytecode);
1312 free(exclusion);
1313 ret = LTTNG_ERR_FILTER_INVAL;
1314 goto error;
1315 }
1316
1317 if ((bytecode->len + sizeof(*bytecode)) != bytecode_len) {
1318 free(filter_expression);
1319 free(bytecode);
1320 free(exclusion);
1321 ret = LTTNG_ERR_FILTER_INVAL;
1322 goto error;
1323 }
1324 }
1325
df4f5a87 1326 ev = lttng_event_copy(ALIGNED_CONST_PTR(cmd_ctx->lsm->u.enable.event));
917a718d
JG
1327 if (!ev) {
1328 DBG("Failed to copy event: %s",
1329 cmd_ctx->lsm->u.enable.event.name);
1330 free(filter_expression);
1331 free(bytecode);
1332 free(exclusion);
1333 ret = LTTNG_ERR_NOMEM;
1334 goto error;
1335 }
1336
1337
1338 if (cmd_ctx->lsm->u.enable.userspace_probe_location_len > 0) {
1339 /* Expect a userspace probe description. */
3e3665b8 1340 ret = receive_userspace_probe(cmd_ctx, *sock, sock_error, ev);
917a718d
JG
1341 if (ret) {
1342 free(filter_expression);
1343 free(bytecode);
1344 free(exclusion);
1345 lttng_event_destroy(ev);
1346 goto error;
1347 }
1348 }
1349
df4f5a87
JG
1350 ret = cmd_enable_event(cmd_ctx->session,
1351 ALIGNED_CONST_PTR(cmd_ctx->lsm->domain),
917a718d
JG
1352 cmd_ctx->lsm->u.enable.channel_name,
1353 ev,
1354 filter_expression, bytecode, exclusion,
1355 kernel_poll_pipe[1]);
1356 lttng_event_destroy(ev);
1357 break;
1358 }
1359 case LTTNG_LIST_TRACEPOINTS:
1360 {
1361 struct lttng_event *events;
1362 ssize_t nb_events;
1363
1364 session_lock_list();
1365 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
1366 session_unlock_list();
1367 if (nb_events < 0) {
1368 /* Return value is a negative lttng_error_code. */
1369 ret = -nb_events;
1370 goto error;
1371 }
1372
1373 /*
1374 * Setup lttng message with payload size set to the event list size in
1375 * bytes and then copy list into the llm payload.
1376 */
1377 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, events,
1378 sizeof(struct lttng_event) * nb_events);
1379 free(events);
1380
1381 if (ret < 0) {
1382 goto setup_error;
1383 }
1384
1385 ret = LTTNG_OK;
1386 break;
1387 }
1388 case LTTNG_LIST_TRACEPOINT_FIELDS:
1389 {
1390 struct lttng_event_field *fields;
1391 ssize_t nb_fields;
1392
1393 session_lock_list();
1394 nb_fields = cmd_list_tracepoint_fields(cmd_ctx->lsm->domain.type,
1395 &fields);
1396 session_unlock_list();
1397 if (nb_fields < 0) {
1398 /* Return value is a negative lttng_error_code. */
1399 ret = -nb_fields;
1400 goto error;
1401 }
1402
1403 /*
1404 * Setup lttng message with payload size set to the event list size in
1405 * bytes and then copy list into the llm payload.
1406 */
1407 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, fields,
1408 sizeof(struct lttng_event_field) * nb_fields);
1409 free(fields);
1410
1411 if (ret < 0) {
1412 goto setup_error;
1413 }
1414
1415 ret = LTTNG_OK;
1416 break;
1417 }
1418 case LTTNG_LIST_SYSCALLS:
1419 {
1420 struct lttng_event *events;
1421 ssize_t nb_events;
1422
1423 nb_events = cmd_list_syscalls(&events);
1424 if (nb_events < 0) {
1425 /* Return value is a negative lttng_error_code. */
1426 ret = -nb_events;
1427 goto error;
1428 }
1429
1430 /*
1431 * Setup lttng message with payload size set to the event list size in
1432 * bytes and then copy list into the llm payload.
1433 */
1434 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, events,
1435 sizeof(struct lttng_event) * nb_events);
1436 free(events);
1437
1438 if (ret < 0) {
1439 goto setup_error;
1440 }
1441
1442 ret = LTTNG_OK;
1443 break;
1444 }
1445 case LTTNG_LIST_TRACKER_PIDS:
1446 {
1447 int32_t *pids = NULL;
1448 ssize_t nr_pids;
1449
1450 nr_pids = cmd_list_tracker_pids(cmd_ctx->session,
1451 cmd_ctx->lsm->domain.type, &pids);
1452 if (nr_pids < 0) {
1453 /* Return value is a negative lttng_error_code. */
1454 ret = -nr_pids;
1455 goto error;
1456 }
1457
1458 /*
1459 * Setup lttng message with payload size set to the event list size in
1460 * bytes and then copy list into the llm payload.
1461 */
1462 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, pids,
1463 sizeof(int32_t) * nr_pids);
1464 free(pids);
1465
1466 if (ret < 0) {
1467 goto setup_error;
1468 }
1469
1470 ret = LTTNG_OK;
1471 break;
1472 }
1473 case LTTNG_SET_CONSUMER_URI:
1474 {
1475 size_t nb_uri, len;
1476 struct lttng_uri *uris;
1477
1478 nb_uri = cmd_ctx->lsm->u.uri.size;
1479 len = nb_uri * sizeof(struct lttng_uri);
1480
1481 if (nb_uri == 0) {
1482 ret = LTTNG_ERR_INVALID;
1483 goto error;
1484 }
1485
1486 uris = zmalloc(len);
1487 if (uris == NULL) {
1488 ret = LTTNG_ERR_FATAL;
1489 goto error;
1490 }
1491
1492 /* Receive variable len data */
1493 DBG("Receiving %zu URI(s) from client ...", nb_uri);
3e3665b8 1494 ret = lttcomm_recv_unix_sock(*sock, uris, len);
917a718d
JG
1495 if (ret <= 0) {
1496 DBG("No URIs received from client... continuing");
1497 *sock_error = 1;
1498 ret = LTTNG_ERR_SESSION_FAIL;
1499 free(uris);
1500 goto error;
1501 }
1502
1503 ret = cmd_set_consumer_uri(cmd_ctx->session, nb_uri, uris);
1504 free(uris);
1505 if (ret != LTTNG_OK) {
1506 goto error;
1507 }
1508
1509
1510 break;
1511 }
1512 case LTTNG_START_TRACE:
1513 {
1514 /*
1515 * On the first start, if we have a kernel session and we have
1516 * enabled time or size-based rotations, we have to make sure
1517 * the kernel tracer supports it.
1518 */
1519 if (!cmd_ctx->session->has_been_started && \
1520 cmd_ctx->session->kernel_session && \
1521 (cmd_ctx->session->rotate_timer_period || \
1522 cmd_ctx->session->rotate_size) && \
1523 !check_rotate_compatible()) {
1524 DBG("Kernel tracer version is not compatible with the rotation feature");
1525 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
1526 goto error;
1527 }
1528 ret = cmd_start_trace(cmd_ctx->session);
1529 break;
1530 }
1531 case LTTNG_STOP_TRACE:
1532 {
1533 ret = cmd_stop_trace(cmd_ctx->session);
1534 break;
1535 }
917a718d
JG
1536 case LTTNG_DESTROY_SESSION:
1537 {
1538 ret = cmd_destroy_session(cmd_ctx->session,
3e3665b8
JG
1539 notification_thread_handle,
1540 sock);
917a718d
JG
1541 break;
1542 }
1543 case LTTNG_LIST_DOMAINS:
1544 {
1545 ssize_t nb_dom;
1546 struct lttng_domain *domains = NULL;
1547
1548 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
1549 if (nb_dom < 0) {
1550 /* Return value is a negative lttng_error_code. */
1551 ret = -nb_dom;
1552 goto error;
1553 }
1554
1555 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, domains,
1556 nb_dom * sizeof(struct lttng_domain));
1557 free(domains);
1558
1559 if (ret < 0) {
1560 goto setup_error;
1561 }
1562
1563 ret = LTTNG_OK;
1564 break;
1565 }
1566 case LTTNG_LIST_CHANNELS:
1567 {
1568 ssize_t payload_size;
1569 struct lttng_channel *channels = NULL;
1570
1571 payload_size = cmd_list_channels(cmd_ctx->lsm->domain.type,
1572 cmd_ctx->session, &channels);
1573 if (payload_size < 0) {
1574 /* Return value is a negative lttng_error_code. */
1575 ret = -payload_size;
1576 goto error;
1577 }
1578
1579 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, channels,
1580 payload_size);
1581 free(channels);
1582
1583 if (ret < 0) {
1584 goto setup_error;
1585 }
1586
1587 ret = LTTNG_OK;
1588 break;
1589 }
1590 case LTTNG_LIST_EVENTS:
1591 {
1592 ssize_t nb_event;
1593 struct lttng_event *events = NULL;
1594 struct lttcomm_event_command_header cmd_header;
1595 size_t total_size;
1596
1597 memset(&cmd_header, 0, sizeof(cmd_header));
1598 /* Extended infos are included at the end of events */
1599 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type,
1600 cmd_ctx->session, cmd_ctx->lsm->u.list.channel_name,
1601 &events, &total_size);
1602
1603 if (nb_event < 0) {
1604 /* Return value is a negative lttng_error_code. */
1605 ret = -nb_event;
1606 goto error;
1607 }
1608
1609 cmd_header.nb_events = nb_event;
1610 ret = setup_lttng_msg(cmd_ctx, events, total_size,
1611 &cmd_header, sizeof(cmd_header));
1612 free(events);
1613
1614 if (ret < 0) {
1615 goto setup_error;
1616 }
1617
1618 ret = LTTNG_OK;
1619 break;
1620 }
1621 case LTTNG_LIST_SESSIONS:
1622 {
1623 unsigned int nr_sessions;
1624 void *sessions_payload;
1625 size_t payload_len;
1626
1627 session_lock_list();
1628 nr_sessions = lttng_sessions_count(
1629 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1630 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
b178f53e
JG
1631
1632 payload_len = (sizeof(struct lttng_session) * nr_sessions) +
1633 (sizeof(struct lttng_session_extended) * nr_sessions);
917a718d
JG
1634 sessions_payload = zmalloc(payload_len);
1635
1636 if (!sessions_payload) {
1637 session_unlock_list();
1638 ret = -ENOMEM;
1639 goto setup_error;
1640 }
1641
b178f53e 1642 cmd_list_lttng_sessions(sessions_payload, nr_sessions,
917a718d
JG
1643 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
1644 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
1645 session_unlock_list();
1646
1647 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, sessions_payload,
1648 payload_len);
1649 free(sessions_payload);
1650
1651 if (ret < 0) {
1652 goto setup_error;
1653 }
1654
1655 ret = LTTNG_OK;
1656 break;
1657 }
1658 case LTTNG_REGISTER_CONSUMER:
1659 {
1660 struct consumer_data *cdata;
1661
1662 switch (cmd_ctx->lsm->domain.type) {
1663 case LTTNG_DOMAIN_KERNEL:
1664 cdata = &kconsumer_data;
1665 break;
1666 default:
1667 ret = LTTNG_ERR_UND;
1668 goto error;
1669 }
1670
1671 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
1672 cmd_ctx->lsm->u.reg.path, cdata);
1673 break;
1674 }
1675 case LTTNG_DATA_PENDING:
1676 {
1677 int pending_ret;
1678 uint8_t pending_ret_byte;
1679
1680 pending_ret = cmd_data_pending(cmd_ctx->session);
1681
1682 /*
1683 * FIXME
1684 *
1685 * This function may returns 0 or 1 to indicate whether or not
1686 * there is data pending. In case of error, it should return an
1687 * LTTNG_ERR code. However, some code paths may still return
1688 * a nondescript error code, which we handle by returning an
1689 * "unknown" error.
1690 */
1691 if (pending_ret == 0 || pending_ret == 1) {
1692 /*
1693 * ret will be set to LTTNG_OK at the end of
1694 * this function.
1695 */
1696 } else if (pending_ret < 0) {
1697 ret = LTTNG_ERR_UNK;
1698 goto setup_error;
1699 } else {
1700 ret = pending_ret;
1701 goto setup_error;
1702 }
1703
1704 pending_ret_byte = (uint8_t) pending_ret;
1705
1706 /* 1 byte to return whether or not data is pending */
1707 ret = setup_lttng_msg_no_cmd_header(cmd_ctx,
1708 &pending_ret_byte, 1);
1709
1710 if (ret < 0) {
1711 goto setup_error;
1712 }
1713
1714 ret = LTTNG_OK;
1715 break;
1716 }
1717 case LTTNG_SNAPSHOT_ADD_OUTPUT:
1718 {
a914e76a 1719 uint32_t snapshot_id;
917a718d
JG
1720 struct lttcomm_lttng_output_id reply;
1721
1722 ret = cmd_snapshot_add_output(cmd_ctx->session,
df4f5a87
JG
1723 ALIGNED_CONST_PTR(cmd_ctx->lsm->u.snapshot_output.output),
1724 &snapshot_id);
917a718d
JG
1725 if (ret != LTTNG_OK) {
1726 goto error;
1727 }
a914e76a 1728 reply.id = snapshot_id;
917a718d
JG
1729
1730 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &reply,
1731 sizeof(reply));
1732 if (ret < 0) {
1733 goto setup_error;
1734 }
1735
1736 /* Copy output list into message payload */
1737 ret = LTTNG_OK;
1738 break;
1739 }
1740 case LTTNG_SNAPSHOT_DEL_OUTPUT:
1741 {
1742 ret = cmd_snapshot_del_output(cmd_ctx->session,
df4f5a87 1743 ALIGNED_CONST_PTR(cmd_ctx->lsm->u.snapshot_output.output));
917a718d
JG
1744 break;
1745 }
1746 case LTTNG_SNAPSHOT_LIST_OUTPUT:
1747 {
1748 ssize_t nb_output;
1749 struct lttng_snapshot_output *outputs = NULL;
1750
1751 nb_output = cmd_snapshot_list_outputs(cmd_ctx->session, &outputs);
1752 if (nb_output < 0) {
1753 ret = -nb_output;
1754 goto error;
1755 }
1756
1757 assert((nb_output > 0 && outputs) || nb_output == 0);
1758 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, outputs,
1759 nb_output * sizeof(struct lttng_snapshot_output));
1760 free(outputs);
1761
1762 if (ret < 0) {
1763 goto setup_error;
1764 }
1765
1766 ret = LTTNG_OK;
1767 break;
1768 }
1769 case LTTNG_SNAPSHOT_RECORD:
1770 {
1771 ret = cmd_snapshot_record(cmd_ctx->session,
df4f5a87 1772 ALIGNED_CONST_PTR(cmd_ctx->lsm->u.snapshot_record.output),
917a718d
JG
1773 cmd_ctx->lsm->u.snapshot_record.wait);
1774 break;
1775 }
b178f53e 1776 case LTTNG_CREATE_SESSION_EXT:
917a718d 1777 {
b178f53e
JG
1778 struct lttng_dynamic_buffer payload;
1779 struct lttng_session_descriptor *return_descriptor = NULL;
917a718d 1780
b178f53e 1781 lttng_dynamic_buffer_init(&payload);
3e3665b8 1782 ret = cmd_create_session(cmd_ctx, *sock, &return_descriptor);
b178f53e
JG
1783 if (ret != LTTNG_OK) {
1784 goto error;
917a718d
JG
1785 }
1786
b178f53e
JG
1787 ret = lttng_session_descriptor_serialize(return_descriptor,
1788 &payload);
1789 if (ret) {
1790 ERR("Failed to serialize session descriptor in reply to \"create session\" command");
1791 lttng_session_descriptor_destroy(return_descriptor);
1792 ret = LTTNG_ERR_NOMEM;
1793 goto error;
917a718d 1794 }
b178f53e
JG
1795 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, payload.data,
1796 payload.size);
1797 if (ret) {
1798 lttng_session_descriptor_destroy(return_descriptor);
1799 ret = LTTNG_ERR_NOMEM;
1800 goto error;
1801 }
1802 lttng_dynamic_buffer_reset(&payload);
1803 lttng_session_descriptor_destroy(return_descriptor);
1804 ret = LTTNG_OK;
917a718d
JG
1805 break;
1806 }
1807 case LTTNG_SAVE_SESSION:
1808 {
1809 ret = cmd_save_sessions(&cmd_ctx->lsm->u.save_session.attr,
1810 &cmd_ctx->creds);
1811 break;
1812 }
1813 case LTTNG_SET_SESSION_SHM_PATH:
1814 {
1815 ret = cmd_set_session_shm_path(cmd_ctx->session,
1816 cmd_ctx->lsm->u.set_shm_path.shm_path);
1817 break;
1818 }
1819 case LTTNG_REGENERATE_METADATA:
1820 {
1821 ret = cmd_regenerate_metadata(cmd_ctx->session);
1822 break;
1823 }
1824 case LTTNG_REGENERATE_STATEDUMP:
1825 {
1826 ret = cmd_regenerate_statedump(cmd_ctx->session);
1827 break;
1828 }
1829 case LTTNG_REGISTER_TRIGGER:
1830 {
3e3665b8 1831 ret = cmd_register_trigger(cmd_ctx, *sock,
917a718d
JG
1832 notification_thread_handle);
1833 break;
1834 }
1835 case LTTNG_UNREGISTER_TRIGGER:
1836 {
3e3665b8 1837 ret = cmd_unregister_trigger(cmd_ctx, *sock,
917a718d
JG
1838 notification_thread_handle);
1839 break;
1840 }
1841 case LTTNG_ROTATE_SESSION:
1842 {
1843 struct lttng_rotate_session_return rotate_return;
1844
1845 DBG("Client rotate session \"%s\"", cmd_ctx->session->name);
1846
1847 memset(&rotate_return, 0, sizeof(rotate_return));
1848 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
1849 DBG("Kernel tracer version is not compatible with the rotation feature");
1850 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
1851 goto error;
1852 }
1853
7fdbed1c 1854 ret = cmd_rotate_session(cmd_ctx->session, &rotate_return,
343defc2
MD
1855 false,
1856 LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED);
917a718d
JG
1857 if (ret < 0) {
1858 ret = -ret;
1859 goto error;
1860 }
1861
1862 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &rotate_return,
1863 sizeof(rotate_return));
1864 if (ret < 0) {
1865 ret = -ret;
1866 goto error;
1867 }
1868
1869 ret = LTTNG_OK;
1870 break;
1871 }
1872 case LTTNG_ROTATION_GET_INFO:
1873 {
1874 struct lttng_rotation_get_info_return get_info_return;
1875
1876 memset(&get_info_return, 0, sizeof(get_info_return));
1877 ret = cmd_rotate_get_info(cmd_ctx->session, &get_info_return,
1878 cmd_ctx->lsm->u.get_rotation_info.rotation_id);
1879 if (ret < 0) {
1880 ret = -ret;
1881 goto error;
1882 }
1883
1884 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &get_info_return,
1885 sizeof(get_info_return));
1886 if (ret < 0) {
1887 ret = -ret;
1888 goto error;
1889 }
1890
1891 ret = LTTNG_OK;
1892 break;
1893 }
1894 case LTTNG_ROTATION_SET_SCHEDULE:
1895 {
1896 bool set_schedule;
1897 enum lttng_rotation_schedule_type schedule_type;
1898 uint64_t value;
1899
1900 if (cmd_ctx->session->kernel_session && !check_rotate_compatible()) {
1901 DBG("Kernel tracer version does not support session rotations");
1902 ret = LTTNG_ERR_ROTATION_WRONG_VERSION;
1903 goto error;
1904 }
1905
1906 set_schedule = cmd_ctx->lsm->u.rotation_set_schedule.set == 1;
1907 schedule_type = (enum lttng_rotation_schedule_type) cmd_ctx->lsm->u.rotation_set_schedule.type;
1908 value = cmd_ctx->lsm->u.rotation_set_schedule.value;
1909
1910 ret = cmd_rotation_set_schedule(cmd_ctx->session,
1911 set_schedule,
1912 schedule_type,
1913 value,
1914 notification_thread_handle);
1915 if (ret != LTTNG_OK) {
1916 goto error;
1917 }
1918
1919 break;
1920 }
1921 case LTTNG_SESSION_LIST_ROTATION_SCHEDULES:
1922 {
1923 struct lttng_session_list_schedules_return schedules = {
1924 .periodic.set = !!cmd_ctx->session->rotate_timer_period,
1925 .periodic.value = cmd_ctx->session->rotate_timer_period,
1926 .size.set = !!cmd_ctx->session->rotate_size,
1927 .size.value = cmd_ctx->session->rotate_size,
1928 };
1929
1930 ret = setup_lttng_msg_no_cmd_header(cmd_ctx, &schedules,
1931 sizeof(schedules));
1932 if (ret < 0) {
1933 ret = -ret;
1934 goto error;
1935 }
1936
1937 ret = LTTNG_OK;
1938 break;
1939 }
022349df
MD
1940 case LTTNG_CLEAR_SESSION:
1941 {
1942 ret = cmd_clear_session(cmd_ctx->session, sock);
1943 break;
1944 }
917a718d
JG
1945 default:
1946 ret = LTTNG_ERR_UND;
1947 break;
1948 }
1949
1950error:
1951 if (cmd_ctx->llm == NULL) {
1952 DBG("Missing llm structure. Allocating one.");
1953 if (setup_lttng_msg_no_cmd_header(cmd_ctx, NULL, 0) < 0) {
1954 goto setup_error;
1955 }
1956 }
1957 /* Set return code */
1958 cmd_ctx->llm->ret_code = ret;
1959setup_error:
1960 if (cmd_ctx->session) {
1961 session_unlock(cmd_ctx->session);
1962 session_put(cmd_ctx->session);
3e3665b8 1963 cmd_ctx->session = NULL;
917a718d
JG
1964 }
1965 if (need_tracing_session) {
1966 session_unlock_list();
1967 }
1968init_setup_error:
1969 assert(!rcu_read_ongoing());
1970 return ret;
1971}
1972
1973static int create_client_sock(void)
1974{
1975 int ret, client_sock;
1976 const mode_t old_umask = umask(0);
1977
1978 /* Create client tool unix socket */
1979 client_sock = lttcomm_create_unix_sock(config.client_unix_sock_path.value);
1980 if (client_sock < 0) {
1981 ERR("Create unix sock failed: %s", config.client_unix_sock_path.value);
1982 ret = -1;
1983 goto end;
1984 }
1985
1986 /* Set the cloexec flag */
1987 ret = utils_set_fd_cloexec(client_sock);
1988 if (ret < 0) {
1989 ERR("Unable to set CLOEXEC flag to the client Unix socket (fd: %d). "
1990 "Continuing but note that the consumer daemon will have a "
1991 "reference to this socket on exec()", client_sock);
1992 }
1993
1994 /* File permission MUST be 660 */
1995 ret = chmod(config.client_unix_sock_path.value, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
1996 if (ret < 0) {
18972083
JR
1997 ERR("Set file permissions failed: %s",
1998 config.client_unix_sock_path.value);
917a718d 1999 PERROR("chmod");
18972083
JR
2000 (void) lttcomm_close_unix_sock(client_sock);
2001 ret = -1;
917a718d
JG
2002 goto end;
2003 }
2004 DBG("Created client socket (fd = %i)", client_sock);
2005 ret = client_sock;
2006end:
2007 umask(old_umask);
2008 return ret;
2009}
2010
2011static void cleanup_client_thread(void *data)
2012{
2013 struct lttng_pipe *quit_pipe = data;
2014
2015 lttng_pipe_destroy(quit_pipe);
2016}
2017
6cb45e93
JG
2018static void thread_init_cleanup(void *data)
2019{
2020 set_thread_status(false);
2021}
2022
917a718d
JG
2023/*
2024 * This thread manage all clients request using the unix client socket for
2025 * communication.
2026 */
2027static void *thread_manage_clients(void *data)
2028{
2029 int sock = -1, ret, i, pollfd, err = -1;
2030 int sock_error;
2031 uint32_t revents, nb_fd;
2032 struct command_ctx *cmd_ctx = NULL;
2033 struct lttng_poll_event events;
0f68efb6 2034 const int client_sock = thread_state.client_sock;
917a718d
JG
2035 struct lttng_pipe *quit_pipe = data;
2036 const int thread_quit_pipe_fd = lttng_pipe_get_readfd(quit_pipe);
2037
2038 DBG("[thread] Manage client started");
2039
2040 is_root = (getuid() == 0);
2041
6cb45e93 2042 pthread_cleanup_push(thread_init_cleanup, NULL);
917a718d
JG
2043
2044 rcu_register_thread();
2045
2046 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_CMD);
2047
2048 health_code_update();
2049
2050 ret = lttcomm_listen_unix_sock(client_sock);
2051 if (ret < 0) {
2052 goto error_listen;
2053 }
2054
2055 /*
2056 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2057 * more will be added to this poll set.
2058 */
2059 ret = lttng_poll_create(&events, 2, LTTNG_CLOEXEC);
2060 if (ret < 0) {
2061 goto error_create_poll;
2062 }
2063
2064 /* Add the application registration socket */
2065 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
2066 if (ret < 0) {
2067 goto error;
2068 }
2069
2070 /* Add thread quit pipe */
2071 ret = lttng_poll_add(&events, thread_quit_pipe_fd, LPOLLIN | LPOLLERR);
2072 if (ret < 0) {
2073 goto error;
2074 }
2075
6cb45e93
JG
2076 /* Set state as running. */
2077 set_thread_status(true);
2078 pthread_cleanup_pop(0);
2079
917a718d
JG
2080 /* This testpoint is after we signal readiness to the parent. */
2081 if (testpoint(sessiond_thread_manage_clients)) {
2082 goto error;
2083 }
2084
2085 if (testpoint(sessiond_thread_manage_clients_before_loop)) {
2086 goto error;
2087 }
2088
2089 health_code_update();
2090
917a718d
JG
2091 while (1) {
2092 const struct cmd_completion_handler *cmd_completion_handler;
2093
2094 DBG("Accepting client command ...");
2095
2096 /* Inifinite blocking call, waiting for transmission */
2097 restart:
2098 health_poll_entry();
2099 ret = lttng_poll_wait(&events, -1);
2100 health_poll_exit();
2101 if (ret < 0) {
2102 /*
2103 * Restart interrupted system call.
2104 */
2105 if (errno == EINTR) {
2106 goto restart;
2107 }
2108 goto error;
2109 }
2110
2111 nb_fd = ret;
2112
2113 for (i = 0; i < nb_fd; i++) {
2114 revents = LTTNG_POLL_GETEV(&events, i);
2115 pollfd = LTTNG_POLL_GETFD(&events, i);
2116
2117 health_code_update();
2118
917a718d
JG
2119 if (pollfd == thread_quit_pipe_fd) {
2120 err = 0;
2121 goto exit;
2122 } else {
2123 /* Event on the registration socket */
2124 if (revents & LPOLLIN) {
2125 continue;
2126 } else if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2127 ERR("Client socket poll error");
2128 goto error;
2129 } else {
2130 ERR("Unexpected poll events %u for sock %d", revents, pollfd);
2131 goto error;
2132 }
2133 }
2134 }
2135
2136 DBG("Wait for client response");
2137
2138 health_code_update();
2139
2140 sock = lttcomm_accept_unix_sock(client_sock);
2141 if (sock < 0) {
2142 goto error;
2143 }
2144
2145 /*
2146 * Set the CLOEXEC flag. Return code is useless because either way, the
2147 * show must go on.
2148 */
2149 (void) utils_set_fd_cloexec(sock);
2150
2151 /* Set socket option for credentials retrieval */
2152 ret = lttcomm_setsockopt_creds_unix_sock(sock);
2153 if (ret < 0) {
2154 goto error;
2155 }
2156
2157 /* Allocate context command to process the client request */
2158 cmd_ctx = zmalloc(sizeof(struct command_ctx));
2159 if (cmd_ctx == NULL) {
2160 PERROR("zmalloc cmd_ctx");
2161 goto error;
2162 }
2163
2164 /* Allocate data buffer for reception */
2165 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
2166 if (cmd_ctx->lsm == NULL) {
2167 PERROR("zmalloc cmd_ctx->lsm");
2168 goto error;
2169 }
2170
2171 cmd_ctx->llm = NULL;
2172 cmd_ctx->session = NULL;
2173
2174 health_code_update();
2175
2176 /*
2177 * Data is received from the lttng client. The struct
2178 * lttcomm_session_msg (lsm) contains the command and data request of
2179 * the client.
2180 */
2181 DBG("Receiving data from client ...");
2182 ret = lttcomm_recv_creds_unix_sock(sock, cmd_ctx->lsm,
2183 sizeof(struct lttcomm_session_msg), &cmd_ctx->creds);
2184 if (ret <= 0) {
2185 DBG("Nothing recv() from client... continuing");
2186 ret = close(sock);
2187 if (ret) {
2188 PERROR("close");
2189 }
2190 sock = -1;
2191 clean_command_ctx(&cmd_ctx);
2192 continue;
2193 }
2194
2195 health_code_update();
2196
2197 // TODO: Validate cmd_ctx including sanity check for
2198 // security purpose.
2199
2200 rcu_thread_online();
2201 /*
2202 * This function dispatch the work to the kernel or userspace tracer
2203 * libs and fill the lttcomm_lttng_msg data structure of all the needed
2204 * informations for the client. The command context struct contains
2205 * everything this function may needs.
2206 */
3e3665b8 2207 ret = process_client_msg(cmd_ctx, &sock, &sock_error);
917a718d
JG
2208 rcu_thread_offline();
2209 if (ret < 0) {
3e3665b8
JG
2210 if (sock >= 0) {
2211 ret = close(sock);
2212 if (ret) {
2213 PERROR("close");
2214 }
2215 }
2216 sock = -1;
917a718d
JG
2217 /*
2218 * TODO: Inform client somehow of the fatal error. At
2219 * this point, ret < 0 means that a zmalloc failed
2220 * (ENOMEM). Error detected but still accept
2221 * command, unless a socket error has been
2222 * detected.
2223 */
2224 clean_command_ctx(&cmd_ctx);
2225 continue;
2226 }
2227
2228 cmd_completion_handler = cmd_pop_completion_handler();
2229 if (cmd_completion_handler) {
2230 enum lttng_error_code completion_code;
2231
2232 completion_code = cmd_completion_handler->run(
2233 cmd_completion_handler->data);
2234 if (completion_code != LTTNG_OK) {
2235 clean_command_ctx(&cmd_ctx);
2236 continue;
2237 }
2238 }
2239
2240 health_code_update();
2241
3e3665b8
JG
2242 if (sock >= 0) {
2243 DBG("Sending response (size: %d, retcode: %s (%d))",
2244 cmd_ctx->lttng_msg_size,
2245 lttng_strerror(-cmd_ctx->llm->ret_code),
2246 cmd_ctx->llm->ret_code);
2247 ret = send_unix_sock(sock, cmd_ctx->llm,
2248 cmd_ctx->lttng_msg_size);
2249 if (ret < 0) {
2250 ERR("Failed to send data back to client");
2251 }
917a718d 2252
3e3665b8
JG
2253 /* End of transmission */
2254 ret = close(sock);
2255 if (ret) {
2256 PERROR("close");
2257 }
2258 }
2259 sock = -1;
917a718d
JG
2260
2261 clean_command_ctx(&cmd_ctx);
2262
2263 health_code_update();
2264 }
2265
2266exit:
2267error:
2268 if (sock >= 0) {
2269 ret = close(sock);
2270 if (ret) {
2271 PERROR("close");
2272 }
2273 }
2274
2275 lttng_poll_clean(&events);
2276 clean_command_ctx(&cmd_ctx);
2277
2278error_listen:
2279error_create_poll:
2280 unlink(config.client_unix_sock_path.value);
0f68efb6
JG
2281 ret = close(client_sock);
2282 if (ret) {
2283 PERROR("close");
917a718d
JG
2284 }
2285
2286 if (err) {
2287 health_error();
2288 ERR("Health error occurred in %s", __func__);
2289 }
2290
2291 health_unregister(health_sessiond);
2292
2293 DBG("Client thread dying");
2294
2295 rcu_unregister_thread();
917a718d
JG
2296 return NULL;
2297}
2298
2299static
2300bool shutdown_client_thread(void *thread_data)
2301{
2302 struct lttng_pipe *client_quit_pipe = thread_data;
2303 const int write_fd = lttng_pipe_get_writefd(client_quit_pipe);
2304
2305 return notify_thread_pipe(write_fd) == 1;
2306}
2307
2308struct lttng_thread *launch_client_thread(void)
2309{
6cb45e93 2310 bool thread_running;
917a718d 2311 struct lttng_pipe *client_quit_pipe;
0f68efb6
JG
2312 struct lttng_thread *thread = NULL;
2313 int client_sock_fd = -1;
917a718d 2314
6cb45e93 2315 sem_init(&thread_state.ready, 0, 0);
917a718d
JG
2316 client_quit_pipe = lttng_pipe_open(FD_CLOEXEC);
2317 if (!client_quit_pipe) {
2318 goto error;
2319 }
2320
0f68efb6
JG
2321 client_sock_fd = create_client_sock();
2322 if (client_sock_fd < 0) {
2323 goto error;
2324 }
2325
2326 thread_state.client_sock = client_sock_fd;
917a718d
JG
2327 thread = lttng_thread_create("Client management",
2328 thread_manage_clients,
2329 shutdown_client_thread,
2330 cleanup_client_thread,
2331 client_quit_pipe);
2332 if (!thread) {
2333 goto error;
2334 }
0f68efb6
JG
2335 /* The client thread now owns the client sock fd and the quit pipe. */
2336 client_sock_fd = -1;
2337 client_quit_pipe = NULL;
917a718d
JG
2338
2339 /*
2340 * This thread is part of the threads that need to be fully
2341 * initialized before the session daemon is marked as "ready".
2342 */
6cb45e93
JG
2343 thread_running = wait_thread_status();
2344 if (!thread_running) {
0f68efb6 2345 goto error;
6cb45e93 2346 }
917a718d
JG
2347 return thread;
2348error:
0f68efb6
JG
2349 if (client_sock_fd >= 0) {
2350 if (close(client_sock_fd)) {
2351 PERROR("Failed to close client socket");
2352 }
2353 }
2354 lttng_thread_put(thread);
917a718d
JG
2355 cleanup_client_thread(client_quit_pipe);
2356 return NULL;
2357}
This page took 0.202688 seconds and 4 git commands to generate.