src/bin/lttng-sessiond/main.c

   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 #define _LGPL_SOURCE
  21 #include <getopt.h>
  22 #include <grp.h>
  23 #include <limits.h>
  24 #include <paths.h>
  25 #include <pthread.h>
  26 #include <signal.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <inttypes.h>
  31 #include <sys/mman.h>
  32 #include <sys/mount.h>
  33 #include <sys/resource.h>
  34 #include <sys/socket.h>
  35 #include <sys/stat.h>
  36 #include <sys/types.h>
  37 #include <sys/wait.h>
  38 #include <urcu/uatomic.h>
  39 #include <unistd.h>
  40 #include <ctype.h>
  41
  42 #include <common/common.h>
  43 #include <common/compat/socket.h>
  44 #include <common/compat/getenv.h>
  45 #include <common/defaults.h>
  46 #include <common/kernel-consumer/kernel-consumer.h>
  47 #include <common/futex.h>
  48 #include <common/relayd/relayd.h>
  49 #include <common/utils.h>
  50 #include <common/daemonize.h>
  51 #include <common/config/session-config.h>
  52 #include <common/dynamic-buffer.h>
  53 #include <lttng/event-internal.h>
  54
  55 #include "lttng-sessiond.h"
  56 #include "buffer-registry.h"
  57 #include "channel.h"
  58 #include "cmd.h"
  59 #include "consumer.h"
  60 #include "context.h"
  61 #include "event.h"
  62 #include "kernel.h"
  63 #include "kernel-consumer.h"
  64 #include "modprobe.h"
  65 #include "shm.h"
  66 #include "ust-ctl.h"
  67 #include "ust-consumer.h"
  68 #include "utils.h"
  69 #include "fd-limit.h"
  70 #include "health-sessiond.h"
  71 #include "testpoint.h"
  72 #include "notify-apps.h"
  73 #include "agent-thread.h"
  74 #include "save.h"
  75 #include "notification-thread.h"
  76 #include "notification-thread-commands.h"
  77 #include "rotation-thread.h"
  78 #include "lttng-syscall.h"
  79 #include "agent.h"
  80 #include "ht-cleanup.h"
  81 #include "sessiond-config.h"
  82 #include "timer.h"
  83 #include "thread.h"
  84 #include "client.h"
  85 #include "dispatch.h"
  86 #include "register.h"
  87 #include "manage-apps.h"
  88 #include "manage-kernel.h"
  89
  90 static const char *help_msg =
  91 #ifdef LTTNG_EMBED_HELP
  92 #include <lttng-sessiond.8.h>
  93 #else
  94 NULL
  95 #endif
  96 ;
  97
  98 const char *progname;
  99 static int lockfile_fd = -1;
 100
 101 /* Set to 1 when a SIGUSR1 signal is received. */
 102 static int recv_child_signal;
 103
 104 /* Command line options */
 105 static const struct option long_options[] = {
 106         { "client-sock", required_argument, 0, 'c' },
 107         { "apps-sock", required_argument, 0, 'a' },
 108         { "kconsumerd-cmd-sock", required_argument, 0, '\0' },
 109         { "kconsumerd-err-sock", required_argument, 0, '\0' },
 110         { "ustconsumerd32-cmd-sock", required_argument, 0, '\0' },
 111         { "ustconsumerd32-err-sock", required_argument, 0, '\0' },
 112         { "ustconsumerd64-cmd-sock", required_argument, 0, '\0' },
 113         { "ustconsumerd64-err-sock", required_argument, 0, '\0' },
 114         { "consumerd32-path", required_argument, 0, '\0' },
 115         { "consumerd32-libdir", required_argument, 0, '\0' },
 116         { "consumerd64-path", required_argument, 0, '\0' },
 117         { "consumerd64-libdir", required_argument, 0, '\0' },
 118         { "daemonize", no_argument, 0, 'd' },
 119         { "background", no_argument, 0, 'b' },
 120         { "sig-parent", no_argument, 0, 'S' },
 121         { "help", no_argument, 0, 'h' },
 122         { "group", required_argument, 0, 'g' },
 123         { "version", no_argument, 0, 'V' },
 124         { "quiet", no_argument, 0, 'q' },
 125         { "verbose", no_argument, 0, 'v' },
 126         { "verbose-consumer", no_argument, 0, '\0' },
 127         { "no-kernel", no_argument, 0, '\0' },
 128         { "pidfile", required_argument, 0, 'p' },
 129         { "agent-tcp-port", required_argument, 0, '\0' },
 130         { "config", required_argument, 0, 'f' },
 131         { "load", required_argument, 0, 'l' },
 132         { "kmod-probes", required_argument, 0, '\0' },
 133         { "extra-kmod-probes", required_argument, 0, '\0' },
 134         { NULL, 0, 0, 0 }
 135 };
 136
 137 /* Command line options to ignore from configuration file */
 138 static const char *config_ignore_options[] = { "help", "version", "config" };
 139
 140 /*
 141  * This pipe is used to inform the thread managing application communication
 142  * that a command is queued and ready to be processed.
 143  */
 144 static int apps_cmd_pipe[2] = { -1, -1 };
 145 static int apps_cmd_notify_pipe[2] = { -1, -1 };
 146
 147 /*
 148  * UST registration command queue. This queue is tied with a futex and uses a N
 149  * wakers / 1 waiter implemented and detailed in futex.c/.h
 150  *
 151  * The thread_registration_apps and thread_dispatch_ust_registration uses this
 152  * queue along with the wait/wake scheme. The thread_manage_apps receives down
 153  * the line new application socket and monitors it for any I/O error or clean
 154  * close that triggers an unregistration of the application.
 155  */
 156 static struct ust_cmd_queue ust_cmd_queue;
 157
 158 static const char *module_proc_lttng = "/proc/lttng";
 159
 160 /*
 161  * Section name to look for in the daemon configuration file.
 162  */
 163 static const char * const config_section_name = "sessiond";
 164
 165 /* Am I root or not. Set to 1 if the daemon is running as root */
 166 static int is_root;
 167
 168 /*
 169  * Stop all threads by closing the thread quit pipe.
 170  */
 171 static void stop_threads(void)
 172 {
 173         int ret;
 174
 175         /* Stopping all threads */
 176         DBG("Terminating all threads");
 177         ret = sessiond_notify_quit_pipe();
 178         if (ret < 0) {
 179                 ERR("write error on thread quit pipe");
 180         }
 181 }
 182
 183 /*
 184  * Close every consumer sockets.
 185  */
 186 static void close_consumer_sockets(void)
 187 {
 188         int ret;
 189
 190         if (kconsumer_data.err_sock >= 0) {
 191                 ret = close(kconsumer_data.err_sock);
 192                 if (ret < 0) {
 193                         PERROR("kernel consumer err_sock close");
 194                 }
 195         }
 196         if (ustconsumer32_data.err_sock >= 0) {
 197                 ret = close(ustconsumer32_data.err_sock);
 198                 if (ret < 0) {
 199                         PERROR("UST consumerd32 err_sock close");
 200                 }
 201         }
 202         if (ustconsumer64_data.err_sock >= 0) {
 203                 ret = close(ustconsumer64_data.err_sock);
 204                 if (ret < 0) {
 205                         PERROR("UST consumerd64 err_sock close");
 206                 }
 207         }
 208         if (kconsumer_data.cmd_sock >= 0) {
 209                 ret = close(kconsumer_data.cmd_sock);
 210                 if (ret < 0) {
 211                         PERROR("kernel consumer cmd_sock close");
 212                 }
 213         }
 214         if (ustconsumer32_data.cmd_sock >= 0) {
 215                 ret = close(ustconsumer32_data.cmd_sock);
 216                 if (ret < 0) {
 217                         PERROR("UST consumerd32 cmd_sock close");
 218                 }
 219         }
 220         if (ustconsumer64_data.cmd_sock >= 0) {
 221                 ret = close(ustconsumer64_data.cmd_sock);
 222                 if (ret < 0) {
 223                         PERROR("UST consumerd64 cmd_sock close");
 224                 }
 225         }
 226         if (kconsumer_data.channel_monitor_pipe >= 0) {
 227                 ret = close(kconsumer_data.channel_monitor_pipe);
 228                 if (ret < 0) {
 229                         PERROR("kernel consumer channel monitor pipe close");
 230                 }
 231         }
 232         if (ustconsumer32_data.channel_monitor_pipe >= 0) {
 233                 ret = close(ustconsumer32_data.channel_monitor_pipe);
 234                 if (ret < 0) {
 235                         PERROR("UST consumerd32 channel monitor pipe close");
 236                 }
 237         }
 238         if (ustconsumer64_data.channel_monitor_pipe >= 0) {
 239                 ret = close(ustconsumer64_data.channel_monitor_pipe);
 240                 if (ret < 0) {
 241                         PERROR("UST consumerd64 channel monitor pipe close");
 242                 }
 243         }
 244 }
 245
 246 /*
 247  * Wait on consumer process termination.
 248  *
 249  * Need to be called with the consumer data lock held or from a context
 250  * ensuring no concurrent access to data (e.g: cleanup).
 251  */
 252 static void wait_consumer(struct consumer_data *consumer_data)
 253 {
 254         pid_t ret;
 255         int status;
 256
 257         if (consumer_data->pid <= 0) {
 258                 return;
 259         }
 260
 261         DBG("Waiting for complete teardown of consumerd (PID: %d)",
 262                         consumer_data->pid);
 263         ret = waitpid(consumer_data->pid, &status, 0);
 264         if (ret == -1) {
 265                 PERROR("consumerd waitpid pid: %d", consumer_data->pid)
 266         } else  if (!WIFEXITED(status)) {
 267                 ERR("consumerd termination with error: %d",
 268                                 WEXITSTATUS(ret));
 269         }
 270         consumer_data->pid = 0;
 271 }
 272
 273 /*
 274  * Cleanup the session daemon's data structures.
 275  */
 276 static void sessiond_cleanup(void)
 277 {
 278         int ret;
 279         struct ltt_session_list *session_list = session_get_list();
 280
 281         DBG("Cleanup sessiond");
 282
 283         /*
 284          * Close the thread quit pipe. It has already done its job,
 285          * since we are now called.
 286          */
 287         sessiond_close_quit_pipe();
 288         utils_close_pipe(apps_cmd_pipe);
 289         utils_close_pipe(apps_cmd_notify_pipe);
 290         utils_close_pipe(kernel_poll_pipe);
 291
 292         ret = remove(config.pid_file_path.value);
 293         if (ret < 0) {
 294                 PERROR("remove pidfile %s", config.pid_file_path.value);
 295         }
 296
 297         DBG("Removing sessiond and consumerd content of directory %s",
 298                 config.rundir.value);
 299
 300         /* sessiond */
 301         DBG("Removing %s", config.pid_file_path.value);
 302         (void) unlink(config.pid_file_path.value);
 303
 304         DBG("Removing %s", config.agent_port_file_path.value);
 305         (void) unlink(config.agent_port_file_path.value);
 306
 307         /* kconsumerd */
 308         DBG("Removing %s", kconsumer_data.err_unix_sock_path);
 309         (void) unlink(kconsumer_data.err_unix_sock_path);
 310
 311         DBG("Removing directory %s", config.kconsumerd_path.value);
 312         (void) rmdir(config.kconsumerd_path.value);
 313
 314         /* ust consumerd 32 */
 315         DBG("Removing %s", config.consumerd32_err_unix_sock_path.value);
 316         (void) unlink(config.consumerd32_err_unix_sock_path.value);
 317
 318         DBG("Removing directory %s", config.consumerd32_path.value);
 319         (void) rmdir(config.consumerd32_path.value);
 320
 321         /* ust consumerd 64 */
 322         DBG("Removing %s", config.consumerd64_err_unix_sock_path.value);
 323         (void) unlink(config.consumerd64_err_unix_sock_path.value);
 324
 325         DBG("Removing directory %s", config.consumerd64_path.value);
 326         (void) rmdir(config.consumerd64_path.value);
 327
 328         pthread_mutex_destroy(&session_list->lock);
 329
 330         wait_consumer(&kconsumer_data);
 331         wait_consumer(&ustconsumer64_data);
 332         wait_consumer(&ustconsumer32_data);
 333
 334         DBG("Cleaning up all agent apps");
 335         agent_app_ht_clean();
 336
 337         DBG("Closing all UST sockets");
 338         ust_app_clean_list();
 339         buffer_reg_destroy_registries();
 340
 341         if (is_root && !config.no_kernel) {
 342                 DBG2("Closing kernel fd");
 343                 if (kernel_tracer_fd >= 0) {
 344                         ret = close(kernel_tracer_fd);
 345                         if (ret) {
 346                                 PERROR("close");
 347                         }
 348                 }
 349                 DBG("Unloading kernel modules");
 350                 modprobe_remove_lttng_all();
 351                 free(syscall_table);
 352         }
 353
 354         close_consumer_sockets();
 355
 356         /*
 357          * We do NOT rmdir rundir because there are other processes
 358          * using it, for instance lttng-relayd, which can start in
 359          * parallel with this teardown.
 360          */
 361 }
 362
 363 /*
 364  * Cleanup the daemon's option data structures.
 365  */
 366 static void sessiond_cleanup_options(void)
 367 {
 368         DBG("Cleaning up options");
 369
 370         sessiond_config_fini(&config);
 371
 372         run_as_destroy_worker();
 373 }
 374
 375 /*
 376  * Setup necessary data for kernel tracer action.
 377  */
 378 static int init_kernel_tracer(void)
 379 {
 380         int ret;
 381
 382         /* Modprobe lttng kernel modules */
 383         ret = modprobe_lttng_control();
 384         if (ret < 0) {
 385                 goto error;
 386         }
 387
 388         /* Open debugfs lttng */
 389         kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
 390         if (kernel_tracer_fd < 0) {
 391                 DBG("Failed to open %s", module_proc_lttng);
 392                 goto error_open;
 393         }
 394
 395         /* Validate kernel version */
 396         ret = kernel_validate_version(kernel_tracer_fd, &kernel_tracer_version,
 397                         &kernel_tracer_abi_version);
 398         if (ret < 0) {
 399                 goto error_version;
 400         }
 401
 402         ret = modprobe_lttng_data();
 403         if (ret < 0) {
 404                 goto error_modules;
 405         }
 406
 407         ret = kernel_supports_ring_buffer_snapshot_sample_positions(
 408                         kernel_tracer_fd);
 409         if (ret < 0) {
 410                 goto error_modules;
 411         }
 412
 413         if (ret < 1) {
 414                 WARN("Kernel tracer does not support buffer monitoring. "
 415                         "The monitoring timer of channels in the kernel domain "
 416                         "will be set to 0 (disabled).");
 417         }
 418
 419         DBG("Kernel tracer fd %d", kernel_tracer_fd);
 420         return 0;
 421
 422 error_version:
 423         modprobe_remove_lttng_control();
 424         ret = close(kernel_tracer_fd);
 425         if (ret) {
 426                 PERROR("close");
 427         }
 428         kernel_tracer_fd = -1;
 429         return LTTNG_ERR_KERN_VERSION;
 430
 431 error_modules:
 432         ret = close(kernel_tracer_fd);
 433         if (ret) {
 434                 PERROR("close");
 435         }
 436
 437 error_open:
 438         modprobe_remove_lttng_control();
 439
 440 error:
 441         WARN("No kernel tracer available");
 442         kernel_tracer_fd = -1;
 443         if (!is_root) {
 444                 return LTTNG_ERR_NEED_ROOT_SESSIOND;
 445         } else {
 446                 return LTTNG_ERR_KERN_NA;
 447         }
 448 }
 449
 450 static int string_match(const char *str1, const char *str2)
 451 {
 452         return (str1 && str2) && !strcmp(str1, str2);
 453 }
 454
 455 /*
 456  * Take an option from the getopt output and set it in the right variable to be
 457  * used later.
 458  *
 459  * Return 0 on success else a negative value.
 460  */
 461 static int set_option(int opt, const char *arg, const char *optname)
 462 {
 463         int ret = 0;
 464
 465         if (string_match(optname, "client-sock") || opt == 'c') {
 466                 if (!arg || *arg == '\0') {
 467                         ret = -EINVAL;
 468                         goto end;
 469                 }
 470                 if (lttng_is_setuid_setgid()) {
 471                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 472                                 "-c, --client-sock");
 473                 } else {
 474                         config_string_set(&config.client_unix_sock_path,
 475                                         strdup(arg));
 476                         if (!config.client_unix_sock_path.value) {
 477                                 ret = -ENOMEM;
 478                                 PERROR("strdup");
 479                         }
 480                 }
 481         } else if (string_match(optname, "apps-sock") || opt == 'a') {
 482                 if (!arg || *arg == '\0') {
 483                         ret = -EINVAL;
 484                         goto end;
 485                 }
 486                 if (lttng_is_setuid_setgid()) {
 487                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 488                                 "-a, --apps-sock");
 489                 } else {
 490                         config_string_set(&config.apps_unix_sock_path,
 491                                         strdup(arg));
 492                         if (!config.apps_unix_sock_path.value) {
 493                                 ret = -ENOMEM;
 494                                 PERROR("strdup");
 495                         }
 496                 }
 497         } else if (string_match(optname, "daemonize") || opt == 'd') {
 498                 config.daemonize = true;
 499         } else if (string_match(optname, "background") || opt == 'b') {
 500                 config.background = true;
 501         } else if (string_match(optname, "group") || opt == 'g') {
 502                 if (!arg || *arg == '\0') {
 503                         ret = -EINVAL;
 504                         goto end;
 505                 }
 506                 if (lttng_is_setuid_setgid()) {
 507                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 508                                 "-g, --group");
 509                 } else {
 510                         config_string_set(&config.tracing_group_name,
 511                                         strdup(arg));
 512                         if (!config.tracing_group_name.value) {
 513                                 ret = -ENOMEM;
 514                                 PERROR("strdup");
 515                         }
 516                 }
 517         } else if (string_match(optname, "help") || opt == 'h') {
 518                 ret = utils_show_help(8, "lttng-sessiond", help_msg);
 519                 if (ret) {
 520                         ERR("Cannot show --help for `lttng-sessiond`");
 521                         perror("exec");
 522                 }
 523                 exit(ret ? EXIT_FAILURE : EXIT_SUCCESS);
 524         } else if (string_match(optname, "version") || opt == 'V') {
 525                 fprintf(stdout, "%s\n", VERSION);
 526                 exit(EXIT_SUCCESS);
 527         } else if (string_match(optname, "sig-parent") || opt == 'S') {
 528                 config.sig_parent = true;
 529         } else if (string_match(optname, "kconsumerd-err-sock")) {
 530                 if (!arg || *arg == '\0') {
 531                         ret = -EINVAL;
 532                         goto end;
 533                 }
 534                 if (lttng_is_setuid_setgid()) {
 535                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 536                                 "--kconsumerd-err-sock");
 537                 } else {
 538                         config_string_set(&config.kconsumerd_err_unix_sock_path,
 539                                         strdup(arg));
 540                         if (!config.kconsumerd_err_unix_sock_path.value) {
 541                                 ret = -ENOMEM;
 542                                 PERROR("strdup");
 543                         }
 544                 }
 545         } else if (string_match(optname, "kconsumerd-cmd-sock")) {
 546                 if (!arg || *arg == '\0') {
 547                         ret = -EINVAL;
 548                         goto end;
 549                 }
 550                 if (lttng_is_setuid_setgid()) {
 551                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 552                                 "--kconsumerd-cmd-sock");
 553                 } else {
 554                         config_string_set(&config.kconsumerd_cmd_unix_sock_path,
 555                                         strdup(arg));
 556                         if (!config.kconsumerd_cmd_unix_sock_path.value) {
 557                                 ret = -ENOMEM;
 558                                 PERROR("strdup");
 559                         }
 560                 }
 561         } else if (string_match(optname, "ustconsumerd64-err-sock")) {
 562                 if (!arg || *arg == '\0') {
 563                         ret = -EINVAL;
 564                         goto end;
 565                 }
 566                 if (lttng_is_setuid_setgid()) {
 567                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 568                                 "--ustconsumerd64-err-sock");
 569                 } else {
 570                         config_string_set(&config.consumerd64_err_unix_sock_path,
 571                                         strdup(arg));
 572                         if (!config.consumerd64_err_unix_sock_path.value) {
 573                                 ret = -ENOMEM;
 574                                 PERROR("strdup");
 575                         }
 576                 }
 577         } else if (string_match(optname, "ustconsumerd64-cmd-sock")) {
 578                 if (!arg || *arg == '\0') {
 579                         ret = -EINVAL;
 580                         goto end;
 581                 }
 582                 if (lttng_is_setuid_setgid()) {
 583                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 584                                 "--ustconsumerd64-cmd-sock");
 585                 } else {
 586                         config_string_set(&config.consumerd64_cmd_unix_sock_path,
 587                                         strdup(arg));
 588                         if (!config.consumerd64_cmd_unix_sock_path.value) {
 589                                 ret = -ENOMEM;
 590                                 PERROR("strdup");
 591                         }
 592                 }
 593         } else if (string_match(optname, "ustconsumerd32-err-sock")) {
 594                 if (!arg || *arg == '\0') {
 595                         ret = -EINVAL;
 596                         goto end;
 597                 }
 598                 if (lttng_is_setuid_setgid()) {
 599                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 600                                 "--ustconsumerd32-err-sock");
 601                 } else {
 602                         config_string_set(&config.consumerd32_err_unix_sock_path,
 603                                         strdup(arg));
 604                         if (!config.consumerd32_err_unix_sock_path.value) {
 605                                 ret = -ENOMEM;
 606                                 PERROR("strdup");
 607                         }
 608                 }
 609         } else if (string_match(optname, "ustconsumerd32-cmd-sock")) {
 610                 if (!arg || *arg == '\0') {
 611                         ret = -EINVAL;
 612                         goto end;
 613                 }
 614                 if (lttng_is_setuid_setgid()) {
 615                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 616                                 "--ustconsumerd32-cmd-sock");
 617                 } else {
 618                         config_string_set(&config.consumerd32_cmd_unix_sock_path,
 619                                         strdup(arg));
 620                         if (!config.consumerd32_cmd_unix_sock_path.value) {
 621                                 ret = -ENOMEM;
 622                                 PERROR("strdup");
 623                         }
 624                 }
 625         } else if (string_match(optname, "no-kernel")) {
 626                 config.no_kernel = true;
 627         } else if (string_match(optname, "quiet") || opt == 'q') {
 628                 config.quiet = true;
 629         } else if (string_match(optname, "verbose") || opt == 'v') {
 630                 /* Verbose level can increase using multiple -v */
 631                 if (arg) {
 632                         /* Value obtained from config file */
 633                         config.verbose = config_parse_value(arg);
 634                 } else {
 635                         /* -v used on command line */
 636                         config.verbose++;
 637                 }
 638                 /* Clamp value to [0, 3] */
 639                 config.verbose = config.verbose < 0 ? 0 :
 640                         (config.verbose <= 3 ? config.verbose : 3);
 641         } else if (string_match(optname, "verbose-consumer")) {
 642                 if (arg) {
 643                         config.verbose_consumer = config_parse_value(arg);
 644                 } else {
 645                         config.verbose_consumer++;
 646                 }
 647         } else if (string_match(optname, "consumerd32-path")) {
 648                 if (!arg || *arg == '\0') {
 649                         ret = -EINVAL;
 650                         goto end;
 651                 }
 652                 if (lttng_is_setuid_setgid()) {
 653                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 654                                 "--consumerd32-path");
 655                 } else {
 656                         config_string_set(&config.consumerd32_bin_path,
 657                                         strdup(arg));
 658                         if (!config.consumerd32_bin_path.value) {
 659                                 PERROR("strdup");
 660                                 ret = -ENOMEM;
 661                         }
 662                 }
 663         } else if (string_match(optname, "consumerd32-libdir")) {
 664                 if (!arg || *arg == '\0') {
 665                         ret = -EINVAL;
 666                         goto end;
 667                 }
 668                 if (lttng_is_setuid_setgid()) {
 669                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 670                                 "--consumerd32-libdir");
 671                 } else {
 672                         config_string_set(&config.consumerd32_lib_dir,
 673                                         strdup(arg));
 674                         if (!config.consumerd32_lib_dir.value) {
 675                                 PERROR("strdup");
 676                                 ret = -ENOMEM;
 677                         }
 678                 }
 679         } else if (string_match(optname, "consumerd64-path")) {
 680                 if (!arg || *arg == '\0') {
 681                         ret = -EINVAL;
 682                         goto end;
 683                 }
 684                 if (lttng_is_setuid_setgid()) {
 685                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 686                                 "--consumerd64-path");
 687                 } else {
 688                         config_string_set(&config.consumerd64_bin_path,
 689                                         strdup(arg));
 690                         if (!config.consumerd64_bin_path.value) {
 691                                 PERROR("strdup");
 692                                 ret = -ENOMEM;
 693                         }
 694                 }
 695         } else if (string_match(optname, "consumerd64-libdir")) {
 696                 if (!arg || *arg == '\0') {
 697                         ret = -EINVAL;
 698                         goto end;
 699                 }
 700                 if (lttng_is_setuid_setgid()) {
 701                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 702                                 "--consumerd64-libdir");
 703                 } else {
 704                         config_string_set(&config.consumerd64_lib_dir,
 705                                         strdup(arg));
 706                         if (!config.consumerd64_lib_dir.value) {
 707                                 PERROR("strdup");
 708                                 ret = -ENOMEM;
 709                         }
 710                 }
 711         } else if (string_match(optname, "pidfile") || opt == 'p') {
 712                 if (!arg || *arg == '\0') {
 713                         ret = -EINVAL;
 714                         goto end;
 715                 }
 716                 if (lttng_is_setuid_setgid()) {
 717                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 718                                 "-p, --pidfile");
 719                 } else {
 720                         config_string_set(&config.pid_file_path, strdup(arg));
 721                         if (!config.pid_file_path.value) {
 722                                 PERROR("strdup");
 723                                 ret = -ENOMEM;
 724                         }
 725                 }
 726         } else if (string_match(optname, "agent-tcp-port")) {
 727                 if (!arg || *arg == '\0') {
 728                         ret = -EINVAL;
 729                         goto end;
 730                 }
 731                 if (lttng_is_setuid_setgid()) {
 732                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 733                                 "--agent-tcp-port");
 734                 } else {
 735                         unsigned long v;
 736
 737                         errno = 0;
 738                         v = strtoul(arg, NULL, 0);
 739                         if (errno != 0 || !isdigit(arg[0])) {
 740                                 ERR("Wrong value in --agent-tcp-port parameter: %s", arg);
 741                                 return -1;
 742                         }
 743                         if (v == 0 || v >= 65535) {
 744                                 ERR("Port overflow in --agent-tcp-port parameter: %s", arg);
 745                                 return -1;
 746                         }
 747                         config.agent_tcp_port.begin = config.agent_tcp_port.end = (int) v;
 748                         DBG3("Agent TCP port set to non default: %i", (int) v);
 749                 }
 750         } else if (string_match(optname, "load") || opt == 'l') {
 751                 if (!arg || *arg == '\0') {
 752                         ret = -EINVAL;
 753                         goto end;
 754                 }
 755                 if (lttng_is_setuid_setgid()) {
 756                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 757                                 "-l, --load");
 758                 } else {
 759                         config_string_set(&config.load_session_path, strdup(arg));
 760                         if (!config.load_session_path.value) {
 761                                 PERROR("strdup");
 762                                 ret = -ENOMEM;
 763                         }
 764                 }
 765         } else if (string_match(optname, "kmod-probes")) {
 766                 if (!arg || *arg == '\0') {
 767                         ret = -EINVAL;
 768                         goto end;
 769                 }
 770                 if (lttng_is_setuid_setgid()) {
 771                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 772                                 "--kmod-probes");
 773                 } else {
 774                         config_string_set(&config.kmod_probes_list, strdup(arg));
 775                         if (!config.kmod_probes_list.value) {
 776                                 PERROR("strdup");
 777                                 ret = -ENOMEM;
 778                         }
 779                 }
 780         } else if (string_match(optname, "extra-kmod-probes")) {
 781                 if (!arg || *arg == '\0') {
 782                         ret = -EINVAL;
 783                         goto end;
 784                 }
 785                 if (lttng_is_setuid_setgid()) {
 786                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 787                                 "--extra-kmod-probes");
 788                 } else {
 789                         config_string_set(&config.kmod_extra_probes_list,
 790                                         strdup(arg));
 791                         if (!config.kmod_extra_probes_list.value) {
 792                                 PERROR("strdup");
 793                                 ret = -ENOMEM;
 794                         }
 795                 }
 796         } else if (string_match(optname, "config") || opt == 'f') {
 797                 /* This is handled in set_options() thus silent skip. */
 798                 goto end;
 799         } else {
 800                 /* Unknown option or other error.
 801                  * Error is printed by getopt, just return */
 802                 ret = -1;
 803         }
 804
 805 end:
 806         if (ret == -EINVAL) {
 807                 const char *opt_name = "unknown";
 808                 int i;
 809
 810                 for (i = 0; i < sizeof(long_options) / sizeof(struct option);
 811                         i++) {
 812                         if (opt == long_options[i].val) {
 813                                 opt_name = long_options[i].name;
 814                                 break;
 815                         }
 816                 }
 817
 818                 WARN("Invalid argument provided for option \"%s\", using default value.",
 819                         opt_name);
 820         }
 821
 822         return ret;
 823 }
 824
 825 /*
 826  * config_entry_handler_cb used to handle options read from a config file.
 827  * See config_entry_handler_cb comment in common/config/session-config.h for the
 828  * return value conventions.
 829  */
 830 static int config_entry_handler(const struct config_entry *entry, void *unused)
 831 {
 832         int ret = 0, i;
 833
 834         if (!entry || !entry->name || !entry->value) {
 835                 ret = -EINVAL;
 836                 goto end;
 837         }
 838
 839         /* Check if the option is to be ignored */
 840         for (i = 0; i < sizeof(config_ignore_options) / sizeof(char *); i++) {
 841                 if (!strcmp(entry->name, config_ignore_options[i])) {
 842                         goto end;
 843                 }
 844         }
 845
 846         for (i = 0; i < (sizeof(long_options) / sizeof(struct option)) - 1;
 847                 i++) {
 848
 849                 /* Ignore if not fully matched. */
 850                 if (strcmp(entry->name, long_options[i].name)) {
 851                         continue;
 852                 }
 853
 854                 /*
 855                  * If the option takes no argument on the command line, we have to
 856                  * check if the value is "true". We support non-zero numeric values,
 857                  * true, on and yes.
 858                  */
 859                 if (!long_options[i].has_arg) {
 860                         ret = config_parse_value(entry->value);
 861                         if (ret <= 0) {
 862                                 if (ret) {
 863                                         WARN("Invalid configuration value \"%s\" for option %s",
 864                                                         entry->value, entry->name);
 865                                 }
 866                                 /* False, skip boolean config option. */
 867                                 goto end;
 868                         }
 869                 }
 870
 871                 ret = set_option(long_options[i].val, entry->value, entry->name);
 872                 goto end;
 873         }
 874
 875         WARN("Unrecognized option \"%s\" in daemon configuration file.", entry->name);
 876
 877 end:
 878         return ret;
 879 }
 880
 881 /*
 882  * daemon configuration loading and argument parsing
 883  */
 884 static int set_options(int argc, char **argv)
 885 {
 886         int ret = 0, c = 0, option_index = 0;
 887         int orig_optopt = optopt, orig_optind = optind;
 888         char *optstring;
 889         const char *config_path = NULL;
 890
 891         optstring = utils_generate_optstring(long_options,
 892                         sizeof(long_options) / sizeof(struct option));
 893         if (!optstring) {
 894                 ret = -ENOMEM;
 895                 goto end;
 896         }
 897
 898         /* Check for the --config option */
 899         while ((c = getopt_long(argc, argv, optstring, long_options,
 900                                         &option_index)) != -1) {
 901                 if (c == '?') {
 902                         ret = -EINVAL;
 903                         goto end;
 904                 } else if (c != 'f') {
 905                         /* if not equal to --config option. */
 906                         continue;
 907                 }
 908
 909                 if (lttng_is_setuid_setgid()) {
 910                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 911                                 "-f, --config");
 912                 } else {
 913                         config_path = utils_expand_path(optarg);
 914                         if (!config_path) {
 915                                 ERR("Failed to resolve path: %s", optarg);
 916                         }
 917                 }
 918         }
 919
 920         ret = config_get_section_entries(config_path, config_section_name,
 921                         config_entry_handler, NULL);
 922         if (ret) {
 923                 if (ret > 0) {
 924                         ERR("Invalid configuration option at line %i", ret);
 925                         ret = -1;
 926                 }
 927                 goto end;
 928         }
 929
 930         /* Reset getopt's global state */
 931         optopt = orig_optopt;
 932         optind = orig_optind;
 933         while (1) {
 934                 option_index = -1;
 935                 /*
 936                  * getopt_long() will not set option_index if it encounters a
 937                  * short option.
 938                  */
 939                 c = getopt_long(argc, argv, optstring, long_options,
 940                                 &option_index);
 941                 if (c == -1) {
 942                         break;
 943                 }
 944
 945                 /*
 946                  * Pass NULL as the long option name if popt left the index
 947                  * unset.
 948                  */
 949                 ret = set_option(c, optarg,
 950                                 option_index < 0 ? NULL :
 951                                 long_options[option_index].name);
 952                 if (ret < 0) {
 953                         break;
 954                 }
 955         }
 956
 957 end:
 958         free(optstring);
 959         return ret;
 960 }
 961
 962 /*
 963  * Create lockfile using the rundir and return its fd.
 964  */
 965 static int create_lockfile(void)
 966 {
 967         return utils_create_lock_file(config.lock_file_path.value);
 968 }
 969
 970 /*
 971  * Check if the global socket is available, and if a daemon is answering at the
 972  * other side. If yes, error is returned.
 973  *
 974  * Also attempts to create and hold the lock file.
 975  */
 976 static int check_existing_daemon(void)
 977 {
 978         int ret = 0;
 979
 980         /* Is there anybody out there ? */
 981         if (lttng_session_daemon_alive()) {
 982                 ret = -EEXIST;
 983                 goto end;
 984         }
 985
 986         lockfile_fd = create_lockfile();
 987         if (lockfile_fd < 0) {
 988                 ret = -EEXIST;
 989                 goto end;
 990         }
 991 end:
 992         return ret;
 993 }
 994
 995 static void sessiond_cleanup_lock_file(void)
 996 {
 997         int ret;
 998
 999         /*
1000          * Cleanup lock file by deleting it and finaly closing it which will
1001          * release the file system lock.
1002          */
1003         if (lockfile_fd >= 0) {
1004                 ret = remove(config.lock_file_path.value);
1005                 if (ret < 0) {
1006                         PERROR("remove lock file");
1007                 }
1008                 ret = close(lockfile_fd);
1009                 if (ret < 0) {
1010                         PERROR("close lock file");
1011                 }
1012         }
1013 }
1014
1015 /*
1016  * Set the tracing group gid onto the client socket.
1017  *
1018  * Race window between mkdir and chown is OK because we are going from more
1019  * permissive (root.root) to less permissive (root.tracing).
1020  */
1021 static int set_permissions(char *rundir)
1022 {
1023         int ret;
1024         gid_t gid;
1025
1026         gid = utils_get_group_id(config.tracing_group_name.value);
1027
1028         /* Set lttng run dir */
1029         ret = chown(rundir, 0, gid);
1030         if (ret < 0) {
1031                 ERR("Unable to set group on %s", rundir);
1032                 PERROR("chown");
1033         }
1034
1035         /*
1036          * Ensure all applications and tracing group can search the run
1037          * dir. Allow everyone to read the directory, since it does not
1038          * buy us anything to hide its content.
1039          */
1040         ret = chmod(rundir, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH);
1041         if (ret < 0) {
1042                 ERR("Unable to set permissions on %s", rundir);
1043                 PERROR("chmod");
1044         }
1045
1046         /* lttng client socket path */
1047         ret = chown(config.client_unix_sock_path.value, 0, gid);
1048         if (ret < 0) {
1049                 ERR("Unable to set group on %s", config.client_unix_sock_path.value);
1050                 PERROR("chown");
1051         }
1052
1053         /* kconsumer error socket path */
1054         ret = chown(kconsumer_data.err_unix_sock_path, 0, 0);
1055         if (ret < 0) {
1056                 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
1057                 PERROR("chown");
1058         }
1059
1060         /* 64-bit ustconsumer error socket path */
1061         ret = chown(ustconsumer64_data.err_unix_sock_path, 0, 0);
1062         if (ret < 0) {
1063                 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
1064                 PERROR("chown");
1065         }
1066
1067         /* 32-bit ustconsumer compat32 error socket path */
1068         ret = chown(ustconsumer32_data.err_unix_sock_path, 0, 0);
1069         if (ret < 0) {
1070                 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
1071                 PERROR("chown");
1072         }
1073
1074         DBG("All permissions are set");
1075
1076         return ret;
1077 }
1078
1079 /*
1080  * Create the lttng run directory needed for all global sockets and pipe.
1081  */
1082 static int create_lttng_rundir(void)
1083 {
1084         int ret;
1085
1086         DBG3("Creating LTTng run directory: %s", config.rundir.value);
1087
1088         ret = mkdir(config.rundir.value, S_IRWXU);
1089         if (ret < 0) {
1090                 if (errno != EEXIST) {
1091                         ERR("Unable to create %s", config.rundir.value);
1092                         goto error;
1093                 } else {
1094                         ret = 0;
1095                 }
1096         }
1097
1098 error:
1099         return ret;
1100 }
1101
1102 /*
1103  * Setup sockets and directory needed by the consumerds' communication with the
1104  * session daemon.
1105  */
1106 static int set_consumer_sockets(struct consumer_data *consumer_data)
1107 {
1108         int ret;
1109         char *path = NULL;
1110
1111         switch (consumer_data->type) {
1112         case LTTNG_CONSUMER_KERNEL:
1113                 path = config.kconsumerd_path.value;
1114                 break;
1115         case LTTNG_CONSUMER64_UST:
1116                 path = config.consumerd64_path.value;
1117                 break;
1118         case LTTNG_CONSUMER32_UST:
1119                 path = config.consumerd32_path.value;
1120                 break;
1121         default:
1122                 ERR("Consumer type unknown");
1123                 ret = -EINVAL;
1124                 goto error;
1125         }
1126         assert(path);
1127
1128         DBG2("Creating consumer directory: %s", path);
1129
1130         ret = mkdir(path, S_IRWXU | S_IRGRP | S_IXGRP);
1131         if (ret < 0 && errno != EEXIST) {
1132                 PERROR("mkdir");
1133                 ERR("Failed to create %s", path);
1134                 goto error;
1135         }
1136         if (is_root) {
1137                 ret = chown(path, 0, utils_get_group_id(config.tracing_group_name.value));
1138                 if (ret < 0) {
1139                         ERR("Unable to set group on %s", path);
1140                         PERROR("chown");
1141                         goto error;
1142                 }
1143         }
1144
1145         /* Create the consumerd error unix socket */
1146         consumer_data->err_sock =
1147                 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
1148         if (consumer_data->err_sock < 0) {
1149                 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
1150                 ret = -1;
1151                 goto error;
1152         }
1153
1154         /*
1155          * Set the CLOEXEC flag. Return code is useless because either way, the
1156          * show must go on.
1157          */
1158         ret = utils_set_fd_cloexec(consumer_data->err_sock);
1159         if (ret < 0) {
1160                 PERROR("utils_set_fd_cloexec");
1161                 /* continue anyway */
1162         }
1163
1164         /* File permission MUST be 660 */
1165         ret = chmod(consumer_data->err_unix_sock_path,
1166                         S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
1167         if (ret < 0) {
1168                 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
1169                 PERROR("chmod");
1170                 goto error;
1171         }
1172
1173 error:
1174         return ret;
1175 }
1176
1177 /*
1178  * Signal handler for the daemon
1179  *
1180  * Simply stop all worker threads, leaving main() return gracefully after
1181  * joining all threads and calling cleanup().
1182  */
1183 static void sighandler(int sig)
1184 {
1185         switch (sig) {
1186         case SIGINT:
1187                 DBG("SIGINT caught");
1188                 stop_threads();
1189                 break;
1190         case SIGTERM:
1191                 DBG("SIGTERM caught");
1192                 stop_threads();
1193                 break;
1194         case SIGUSR1:
1195                 CMM_STORE_SHARED(recv_child_signal, 1);
1196                 break;
1197         default:
1198                 break;
1199         }
1200 }
1201
1202 /*
1203  * Setup signal handler for :
1204  *              SIGINT, SIGTERM, SIGPIPE
1205  */
1206 static int set_signal_handler(void)
1207 {
1208         int ret = 0;
1209         struct sigaction sa;
1210         sigset_t sigset;
1211
1212         if ((ret = sigemptyset(&sigset)) < 0) {
1213                 PERROR("sigemptyset");
1214                 return ret;
1215         }
1216
1217         sa.sa_mask = sigset;
1218         sa.sa_flags = 0;
1219
1220         sa.sa_handler = sighandler;
1221         if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
1222                 PERROR("sigaction");
1223                 return ret;
1224         }
1225
1226         if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
1227                 PERROR("sigaction");
1228                 return ret;
1229         }
1230
1231         if ((ret = sigaction(SIGUSR1, &sa, NULL)) < 0) {
1232                 PERROR("sigaction");
1233                 return ret;
1234         }
1235
1236         sa.sa_handler = SIG_IGN;
1237         if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
1238                 PERROR("sigaction");
1239                 return ret;
1240         }
1241
1242         DBG("Signal handler set for SIGTERM, SIGUSR1, SIGPIPE and SIGINT");
1243
1244         return ret;
1245 }
1246
1247 /*
1248  * Set open files limit to unlimited. This daemon can open a large number of
1249  * file descriptors in order to consume multiple kernel traces.
1250  */
1251 static void set_ulimit(void)
1252 {
1253         int ret;
1254         struct rlimit lim;
1255
1256         /* The kernel does not allow an infinite limit for open files */
1257         lim.rlim_cur = 65535;
1258         lim.rlim_max = 65535;
1259
1260         ret = setrlimit(RLIMIT_NOFILE, &lim);
1261         if (ret < 0) {
1262                 PERROR("failed to set open files limit");
1263         }
1264 }
1265
1266 static int write_pidfile(void)
1267 {
1268         return utils_create_pid_file(getpid(), config.pid_file_path.value);
1269 }
1270
1271 static int set_clock_plugin_env(void)
1272 {
1273         int ret = 0;
1274         char *env_value = NULL;
1275
1276         if (!config.lttng_ust_clock_plugin.value) {
1277                 goto end;
1278         }
1279
1280         ret = asprintf(&env_value, "LTTNG_UST_CLOCK_PLUGIN=%s",
1281                         config.lttng_ust_clock_plugin.value);
1282         if (ret < 0) {
1283                 PERROR("asprintf");
1284                 goto end;
1285         }
1286
1287         ret = putenv(env_value);
1288         if (ret) {
1289                 free(env_value);
1290                 PERROR("putenv of LTTNG_UST_CLOCK_PLUGIN");
1291                 goto end;
1292         }
1293
1294         DBG("Updated LTTNG_UST_CLOCK_PLUGIN environment variable to \"%s\"",
1295                         config.lttng_ust_clock_plugin.value);
1296 end:
1297         return ret;
1298 }
1299
1300 static void destroy_all_sessions_and_wait(void)
1301 {
1302         struct ltt_session *session, *tmp;
1303         struct ltt_session_list *session_list;
1304
1305         session_list = session_get_list();
1306         DBG("Initiating destruction of all sessions");
1307
1308         if (!session_list) {
1309                 return;
1310         }
1311
1312         session_lock_list();
1313         /* Initiate the destruction of all sessions. */
1314         cds_list_for_each_entry_safe(session, tmp,
1315                         &session_list->head, list) {
1316                 if (!session_get(session)) {
1317                         continue;
1318                 }
1319
1320                 session_lock(session);
1321                 if (session->destroyed) {
1322                         goto unlock_session;
1323                 }
1324                 (void) cmd_stop_trace(session);
1325                 (void) cmd_destroy_session(session,
1326                                 notification_thread_handle);
1327         unlock_session:
1328                 session_unlock(session);
1329                 session_put(session);
1330         }
1331         session_unlock_list();
1332
1333         /* Wait for the destruction of all sessions to complete. */
1334         DBG("Waiting for the destruction of all sessions to complete");
1335         session_list_wait_empty();
1336         DBG("Destruction of all sessions completed");
1337 }
1338
1339 /*
1340  * main
1341  */
1342 int main(int argc, char **argv)
1343 {
1344         int ret = 0, retval = 0;
1345         const char *env_app_timeout;
1346         struct lttng_pipe *ust32_channel_monitor_pipe = NULL,
1347                         *ust64_channel_monitor_pipe = NULL,
1348                         *kernel_channel_monitor_pipe = NULL;
1349         struct lttng_thread *ht_cleanup_thread = NULL;
1350         struct timer_thread_parameters timer_thread_parameters;
1351         /* Rotation thread handle. */
1352         struct rotation_thread_handle *rotation_thread_handle = NULL;
1353         /* Queue of rotation jobs populated by the sessiond-timer. */
1354         struct rotation_thread_timer_queue *rotation_timer_queue = NULL;
1355         struct lttng_thread *client_thread = NULL;
1356         struct lttng_thread *notification_thread = NULL;
1357         struct lttng_thread *register_apps_thread = NULL;
1358
1359         init_kernel_workarounds();
1360
1361         rcu_register_thread();
1362
1363         if (set_signal_handler()) {
1364                 retval = -1;
1365                 goto exit_set_signal_handler;
1366         }
1367
1368         if (timer_signal_init()) {
1369                 retval = -1;
1370                 goto exit_set_signal_handler;
1371         }
1372
1373         page_size = sysconf(_SC_PAGESIZE);
1374         if (page_size < 0) {
1375                 PERROR("sysconf _SC_PAGESIZE");
1376                 page_size = LONG_MAX;
1377                 WARN("Fallback page size to %ld", page_size);
1378         }
1379
1380         ret = sessiond_config_init(&config);
1381         if (ret) {
1382                 retval = -1;
1383                 goto exit_set_signal_handler;
1384         }
1385
1386         /*
1387          * Init config from environment variables.
1388          * Command line option override env configuration per-doc. Do env first.
1389          */
1390         sessiond_config_apply_env_config(&config);
1391
1392         /*
1393          * Parse arguments and load the daemon configuration file.
1394          *
1395          * We have an exit_options exit path to free memory reserved by
1396          * set_options. This is needed because the rest of sessiond_cleanup()
1397          * depends on ht_cleanup_thread, which depends on lttng_daemonize, which
1398          * depends on set_options.
1399          */
1400         progname = argv[0];
1401         if (set_options(argc, argv)) {
1402                 retval = -1;
1403                 goto exit_options;
1404         }
1405
1406         /*
1407          * Resolve all paths received as arguments, configuration option, or
1408          * through environment variable as absolute paths. This is necessary
1409          * since daemonizing causes the sessiond's current working directory
1410          * to '/'.
1411          */
1412         ret = sessiond_config_resolve_paths(&config);
1413         if (ret) {
1414                 goto exit_options;
1415         }
1416
1417         /* Apply config. */
1418         lttng_opt_verbose = config.verbose;
1419         lttng_opt_quiet = config.quiet;
1420         kconsumer_data.err_unix_sock_path =
1421                         config.kconsumerd_err_unix_sock_path.value;
1422         kconsumer_data.cmd_unix_sock_path =
1423                         config.kconsumerd_cmd_unix_sock_path.value;
1424         ustconsumer32_data.err_unix_sock_path =
1425                         config.consumerd32_err_unix_sock_path.value;
1426         ustconsumer32_data.cmd_unix_sock_path =
1427                         config.consumerd32_cmd_unix_sock_path.value;
1428         ustconsumer64_data.err_unix_sock_path =
1429                         config.consumerd64_err_unix_sock_path.value;
1430         ustconsumer64_data.cmd_unix_sock_path =
1431                         config.consumerd64_cmd_unix_sock_path.value;
1432         set_clock_plugin_env();
1433
1434         sessiond_config_log(&config);
1435
1436         if (create_lttng_rundir()) {
1437                 retval = -1;
1438                 goto exit_options;
1439         }
1440
1441         /* Abort launch if a session daemon is already running. */
1442         if (check_existing_daemon()) {
1443                 ERR("A session daemon is already running.");
1444                 retval = -1;
1445                 goto exit_options;
1446         }
1447
1448         /* Daemonize */
1449         if (config.daemonize || config.background) {
1450                 int i;
1451
1452                 ret = lttng_daemonize(&child_ppid, &recv_child_signal,
1453                         !config.background);
1454                 if (ret < 0) {
1455                         retval = -1;
1456                         goto exit_options;
1457                 }
1458
1459                 /*
1460                  * We are in the child. Make sure all other file descriptors are
1461                  * closed, in case we are called with more opened file
1462                  * descriptors than the standard ones and the lock file.
1463                  */
1464                 for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
1465                         if (i == lockfile_fd) {
1466                                 continue;
1467                         }
1468                         (void) close(i);
1469                 }
1470         }
1471
1472         if (run_as_create_worker(argv[0]) < 0) {
1473                 goto exit_create_run_as_worker_cleanup;
1474         }
1475
1476         /*
1477          * Starting from here, we can create threads. This needs to be after
1478          * lttng_daemonize due to RCU.
1479          */
1480
1481         /*
1482          * Initialize the health check subsystem. This call should set the
1483          * appropriate time values.
1484          */
1485         health_sessiond = health_app_create(NR_HEALTH_SESSIOND_TYPES);
1486         if (!health_sessiond) {
1487                 PERROR("health_app_create error");
1488                 retval = -1;
1489                 goto stop_threads;
1490         }
1491
1492         /* Create thread to clean up RCU hash tables */
1493         ht_cleanup_thread = launch_ht_cleanup_thread();
1494         if (!ht_cleanup_thread) {
1495                 retval = -1;
1496                 goto stop_threads;
1497         }
1498
1499         /* Create thread quit pipe */
1500         if (sessiond_init_thread_quit_pipe()) {
1501                 retval = -1;
1502                 goto stop_threads;
1503         }
1504
1505         /* Check if daemon is UID = 0 */
1506         is_root = !getuid();
1507         if (is_root) {
1508                 /* Create global run dir with root access */
1509
1510                 kernel_channel_monitor_pipe = lttng_pipe_open(0);
1511                 if (!kernel_channel_monitor_pipe) {
1512                         ERR("Failed to create kernel consumer channel monitor pipe");
1513                         retval = -1;
1514                         goto stop_threads;
1515                 }
1516                 kconsumer_data.channel_monitor_pipe =
1517                                 lttng_pipe_release_writefd(
1518                                         kernel_channel_monitor_pipe);
1519                 if (kconsumer_data.channel_monitor_pipe < 0) {
1520                         retval = -1;
1521                         goto stop_threads;
1522                 }
1523         }
1524
1525         /* Set consumer initial state */
1526         kernel_consumerd_state = CONSUMER_STOPPED;
1527         ust_consumerd_state = CONSUMER_STOPPED;
1528
1529         ust32_channel_monitor_pipe = lttng_pipe_open(0);
1530         if (!ust32_channel_monitor_pipe) {
1531                 ERR("Failed to create 32-bit user space consumer channel monitor pipe");
1532                 retval = -1;
1533                 goto stop_threads;
1534         }
1535         ustconsumer32_data.channel_monitor_pipe = lttng_pipe_release_writefd(
1536                         ust32_channel_monitor_pipe);
1537         if (ustconsumer32_data.channel_monitor_pipe < 0) {
1538                 retval = -1;
1539                 goto stop_threads;
1540         }
1541
1542         /*
1543          * The rotation_thread_timer_queue structure is shared between the
1544          * sessiond timer thread and the rotation thread. The main thread keeps
1545          * its ownership and destroys it when both threads have been joined.
1546          */
1547         rotation_timer_queue = rotation_thread_timer_queue_create();
1548         if (!rotation_timer_queue) {
1549                 retval = -1;
1550                 goto stop_threads;
1551         }
1552         timer_thread_parameters.rotation_thread_job_queue =
1553                         rotation_timer_queue;
1554
1555         ust64_channel_monitor_pipe = lttng_pipe_open(0);
1556         if (!ust64_channel_monitor_pipe) {
1557                 ERR("Failed to create 64-bit user space consumer channel monitor pipe");
1558                 retval = -1;
1559                 goto stop_threads;
1560         }
1561         ustconsumer64_data.channel_monitor_pipe = lttng_pipe_release_writefd(
1562                         ust64_channel_monitor_pipe);
1563         if (ustconsumer64_data.channel_monitor_pipe < 0) {
1564                 retval = -1;
1565                 goto stop_threads;
1566         }
1567
1568         /*
1569          * Init UST app hash table. Alloc hash table before this point since
1570          * cleanup() can get called after that point.
1571          */
1572         if (ust_app_ht_alloc()) {
1573                 ERR("Failed to allocate UST app hash table");
1574                 retval = -1;
1575                 goto stop_threads;
1576         }
1577
1578         /*
1579          * Initialize agent app hash table. We allocate the hash table here
1580          * since cleanup() can get called after this point.
1581          */
1582         if (agent_app_ht_alloc()) {
1583                 ERR("Failed to allocate Agent app hash table");
1584                 retval = -1;
1585                 goto stop_threads;
1586         }
1587
1588         /*
1589          * These actions must be executed as root. We do that *after* setting up
1590          * the sockets path because we MUST make the check for another daemon using
1591          * those paths *before* trying to set the kernel consumer sockets and init
1592          * kernel tracer.
1593          */
1594         if (is_root) {
1595                 if (set_consumer_sockets(&kconsumer_data)) {
1596                         retval = -1;
1597                         goto stop_threads;
1598                 }
1599
1600                 /* Setup kernel tracer */
1601                 if (!config.no_kernel) {
1602                         init_kernel_tracer();
1603                         if (kernel_tracer_fd >= 0) {
1604                                 ret = syscall_init_table();
1605                                 if (ret < 0) {
1606                                         ERR("Unable to populate syscall table. "
1607                                                 "Syscall tracing won't work "
1608                                                 "for this session daemon.");
1609                                 }
1610                         }
1611                 }
1612
1613                 /* Set ulimit for open files */
1614                 set_ulimit();
1615         }
1616         /* init lttng_fd tracking must be done after set_ulimit. */
1617         lttng_fd_init();
1618
1619         if (set_consumer_sockets(&ustconsumer64_data)) {
1620                 retval = -1;
1621                 goto stop_threads;
1622         }
1623
1624         if (set_consumer_sockets(&ustconsumer32_data)) {
1625                 retval = -1;
1626                 goto stop_threads;
1627         }
1628
1629         /* Get parent pid if -S, --sig-parent is specified. */
1630         if (config.sig_parent) {
1631                 ppid = getppid();
1632         }
1633
1634         /* Setup the kernel pipe for waking up the kernel thread */
1635         if (is_root && !config.no_kernel) {
1636                 if (utils_create_pipe_cloexec(kernel_poll_pipe)) {
1637                         retval = -1;
1638                         goto stop_threads;
1639                 }
1640         }
1641
1642         /* Setup the thread apps communication pipe. */
1643         if (utils_create_pipe_cloexec(apps_cmd_pipe)) {
1644                 retval = -1;
1645                 goto stop_threads;
1646         }
1647
1648         /* Setup the thread apps notify communication pipe. */
1649         if (utils_create_pipe_cloexec(apps_cmd_notify_pipe)) {
1650                 retval = -1;
1651                 goto stop_threads;
1652         }
1653
1654         /* Initialize global buffer per UID and PID registry. */
1655         buffer_reg_init_uid_registry();
1656         buffer_reg_init_pid_registry();
1657
1658         /* Init UST command queue. */
1659         cds_wfcq_init(&ust_cmd_queue.head, &ust_cmd_queue.tail);
1660
1661         cmd_init();
1662
1663         /* Check for the application socket timeout env variable. */
1664         env_app_timeout = getenv(DEFAULT_APP_SOCKET_TIMEOUT_ENV);
1665         if (env_app_timeout) {
1666                 config.app_socket_timeout = atoi(env_app_timeout);
1667         } else {
1668                 config.app_socket_timeout = DEFAULT_APP_SOCKET_RW_TIMEOUT;
1669         }
1670
1671         ret = write_pidfile();
1672         if (ret) {
1673                 ERR("Error in write_pidfile");
1674                 retval = -1;
1675                 goto stop_threads;
1676         }
1677
1678         /* Initialize communication library */
1679         lttcomm_init();
1680         /* Initialize TCP timeout values */
1681         lttcomm_inet_init();
1682
1683         /* Create health-check thread. */
1684         if (!launch_health_management_thread()) {
1685                 retval = -1;
1686                 goto stop_threads;
1687         }
1688
1689         /* notification_thread_data acquires the pipes' read side. */
1690         notification_thread_handle = notification_thread_handle_create(
1691                         ust32_channel_monitor_pipe,
1692                         ust64_channel_monitor_pipe,
1693                         kernel_channel_monitor_pipe);
1694         if (!notification_thread_handle) {
1695                 retval = -1;
1696                 ERR("Failed to create notification thread shared data");
1697                 goto stop_threads;
1698         }
1699
1700         /* Create notification thread. */
1701         notification_thread = launch_notification_thread(
1702                         notification_thread_handle);
1703         if (!notification_thread) {
1704                 retval = -1;
1705                 goto stop_threads;
1706         }
1707
1708         /* Create timer thread. */
1709         if (!launch_timer_thread(&timer_thread_parameters)) {
1710                 retval = -1;
1711                 goto stop_threads;
1712         }
1713
1714         /* rotation_thread_data acquires the pipes' read side. */
1715         rotation_thread_handle = rotation_thread_handle_create(
1716                         rotation_timer_queue,
1717                         notification_thread_handle);
1718         if (!rotation_thread_handle) {
1719                 retval = -1;
1720                 ERR("Failed to create rotation thread shared data");
1721                 stop_threads();
1722                 goto stop_threads;
1723         }
1724
1725         /* Create rotation thread. */
1726         if (!launch_rotation_thread(rotation_thread_handle)) {
1727                 retval = -1;
1728                 goto stop_threads;
1729         }
1730
1731         /* Create thread to manage the client socket */
1732         client_thread = launch_client_thread();
1733         if (!client_thread) {
1734                 retval = -1;
1735                 goto stop_threads;
1736         }
1737
1738         /* Set credentials of the client socket and rundir */
1739         if (is_root && set_permissions(config.rundir.value)) {
1740                 retval = -1;
1741                 goto stop_threads;
1742         }
1743
1744         if (!launch_ust_dispatch_thread(&ust_cmd_queue, apps_cmd_pipe[1],
1745                         apps_cmd_notify_pipe[1])) {
1746                 retval = -1;
1747                 goto stop_threads;
1748         }
1749
1750         /* Create thread to manage application registration. */
1751         register_apps_thread = launch_application_registration_thread(
1752                         &ust_cmd_queue);
1753         if (!register_apps_thread) {
1754                 retval = -1;
1755                 goto stop_threads;
1756         }
1757
1758         /* Create thread to manage application socket */
1759         if (!launch_application_management_thread(apps_cmd_pipe[0])) {
1760                 retval = -1;
1761                 goto stop_threads;
1762         }
1763
1764         /* Create thread to manage application notify socket */
1765         if (!launch_application_notification_thread(apps_cmd_notify_pipe[0])) {
1766                 retval = -1;
1767                 goto stop_threads;
1768         }
1769
1770         /* Create agent management thread. */
1771         if (!launch_agent_management_thread()) {
1772                 retval = -1;
1773                 goto stop_threads;
1774         }
1775
1776         /* Don't start this thread if kernel tracing is not requested nor root */
1777         if (is_root && !config.no_kernel) {
1778                 /* Create kernel thread to manage kernel event */
1779                 if (!launch_kernel_management_thread(kernel_poll_pipe[0])) {
1780                         retval = -1;
1781                         goto stop_threads;
1782                 }
1783         }
1784
1785         /* Load sessions. */
1786         ret = config_load_session(config.load_session_path.value,
1787                         NULL, 1, 1, NULL);
1788         if (ret) {
1789                 ERR("Session load failed: %s", error_get_str(ret));
1790                 retval = -1;
1791                 goto stop_threads;
1792         }
1793
1794         /* Initialization completed. */
1795         sessiond_signal_parents();
1796
1797         /*
1798          * This is where we start awaiting program completion (e.g. through
1799          * signal that asks threads to teardown).
1800          */
1801
1802         /* Initiate teardown once activity occurs on the quit pipe. */
1803         sessiond_wait_for_quit_pipe(-1U);
1804
1805 stop_threads:
1806         /*
1807          * Ensure that the client thread is no longer accepting new commands,
1808          * which could cause new sessions to be created.
1809          */
1810         if (client_thread) {
1811                 lttng_thread_shutdown(client_thread);
1812                 lttng_thread_put(client_thread);
1813         }
1814
1815         destroy_all_sessions_and_wait();
1816
1817         if (register_apps_thread) {
1818                 lttng_thread_shutdown(register_apps_thread);
1819                 lttng_thread_put(register_apps_thread);
1820         }
1821         lttng_thread_list_shutdown_orphans();
1822
1823         /*
1824          * Wait for all pending call_rcu work to complete before tearing
1825          * down data structures. call_rcu worker may be trying to
1826          * perform lookups in those structures.
1827          */
1828         rcu_barrier();
1829         /*
1830          * sessiond_cleanup() is called when no other thread is running, except
1831          * the ht_cleanup thread, which is needed to destroy the hash tables.
1832          */
1833         rcu_thread_online();
1834         sessiond_cleanup();
1835
1836         if (notification_thread) {
1837                 lttng_thread_shutdown(notification_thread);
1838                 lttng_thread_put(notification_thread);
1839         }
1840
1841         /*
1842          * Ensure all prior call_rcu are done. call_rcu callbacks may push
1843          * hash tables to the ht_cleanup thread. Therefore, we ensure that
1844          * the queue is empty before shutting down the clean-up thread.
1845          */
1846         rcu_barrier();
1847
1848         if (ht_cleanup_thread) {
1849                 lttng_thread_shutdown(ht_cleanup_thread);
1850                 lttng_thread_put(ht_cleanup_thread);
1851         }
1852
1853         rcu_thread_offline();
1854         rcu_unregister_thread();
1855
1856         if (rotation_thread_handle) {
1857                 rotation_thread_handle_destroy(rotation_thread_handle);
1858         }
1859
1860         /*
1861          * After the rotation and timer thread have quit, we can safely destroy
1862          * the rotation_timer_queue.
1863          */
1864         rotation_thread_timer_queue_destroy(rotation_timer_queue);
1865         /*
1866          * The teardown of the notification system is performed after the
1867          * session daemon's teardown in order to allow it to be notified
1868          * of the active session and channels at the moment of the teardown.
1869          */
1870         if (notification_thread_handle) {
1871                 notification_thread_handle_destroy(notification_thread_handle);
1872         }
1873         lttng_pipe_destroy(ust32_channel_monitor_pipe);
1874         lttng_pipe_destroy(ust64_channel_monitor_pipe);
1875         lttng_pipe_destroy(kernel_channel_monitor_pipe);
1876
1877         health_app_destroy(health_sessiond);
1878 exit_create_run_as_worker_cleanup:
1879 exit_options:
1880         sessiond_cleanup_lock_file();
1881         sessiond_cleanup_options();
1882
1883 exit_set_signal_handler:
1884         if (!retval) {
1885                 exit(EXIT_SUCCESS);
1886         } else {
1887                 exit(EXIT_FAILURE);
1888         }
1889 }