src/bin/lttng-sessiond/main.c

   1 /*
   2  * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
   3  * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  * Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   5  *
   6  * SPDX-License-Identifier: GPL-2.0-only
   7  *
   8  */
   9
  10 #define _LGPL_SOURCE
  11 #include <getopt.h>
  12 #include <grp.h>
  13 #include <limits.h>
  14 #include <paths.h>
  15 #include <pthread.h>
  16 #include <signal.h>
  17 #include <stdio.h>
  18 #include <stdlib.h>
  19 #include <string.h>
  20 #include <inttypes.h>
  21 #include <sys/mman.h>
  22 #include <sys/mount.h>
  23 #include <sys/resource.h>
  24 #include <sys/socket.h>
  25 #include <sys/stat.h>
  26 #include <sys/types.h>
  27 #include <sys/wait.h>
  28 #include <urcu/uatomic.h>
  29 #include <unistd.h>
  30 #include <ctype.h>
  31
  32 #include <common/common.h>
  33 #include <common/compat/socket.h>
  34 #include <common/compat/getenv.h>
  35 #include <common/defaults.h>
  36 #include <common/kernel-consumer/kernel-consumer.h>
  37 #include <common/futex.h>
  38 #include <common/relayd/relayd.h>
  39 #include <common/utils.h>
  40 #include <common/daemonize.h>
  41 #include <common/config/session-config.h>
  42 #include <common/dynamic-buffer.h>
  43 #include <lttng/event-internal.h>
  44
  45 #include "lttng-sessiond.h"
  46 #include "buffer-registry.h"
  47 #include "channel.h"
  48 #include "cmd.h"
  49 #include "consumer.h"
  50 #include "context.h"
  51 #include "event.h"
  52 #include "kernel.h"
  53 #include "kernel-consumer.h"
  54 #include "shm.h"
  55 #include "lttng-ust-ctl.h"
  56 #include "ust-consumer.h"
  57 #include "utils.h"
  58 #include "fd-limit.h"
  59 #include "health-sessiond.h"
  60 #include "testpoint.h"
  61 #include "notify-apps.h"
  62 #include "agent-thread.h"
  63 #include "save.h"
  64 #include "notification-thread.h"
  65 #include "notification-thread-commands.h"
  66 #include "rotation-thread.h"
  67 #include "agent.h"
  68 #include "ht-cleanup.h"
  69 #include "sessiond-config.h"
  70 #include "timer.h"
  71 #include "thread.h"
  72 #include "client.h"
  73 #include "dispatch.h"
  74 #include "register.h"
  75 #include "manage-apps.h"
  76 #include "manage-kernel.h"
  77
  78 static const char *help_msg =
  79 #ifdef LTTNG_EMBED_HELP
  80 #include <lttng-sessiond.8.h>
  81 #else
  82 NULL
  83 #endif
  84 ;
  85
  86 const char *progname;
  87 static int lockfile_fd = -1;
  88 static int opt_print_version;
  89
  90 /* Set to 1 when a SIGUSR1 signal is received. */
  91 static int recv_child_signal;
  92
  93 /* Command line options */
  94 static const struct option long_options[] = {
  95         { "client-sock", required_argument, 0, 'c' },
  96         { "apps-sock", required_argument, 0, 'a' },
  97         { "kconsumerd-cmd-sock", required_argument, 0, '\0' },
  98         { "kconsumerd-err-sock", required_argument, 0, '\0' },
  99         { "ustconsumerd32-cmd-sock", required_argument, 0, '\0' },
 100         { "ustconsumerd32-err-sock", required_argument, 0, '\0' },
 101         { "ustconsumerd64-cmd-sock", required_argument, 0, '\0' },
 102         { "ustconsumerd64-err-sock", required_argument, 0, '\0' },
 103         { "consumerd32-path", required_argument, 0, '\0' },
 104         { "consumerd32-libdir", required_argument, 0, '\0' },
 105         { "consumerd64-path", required_argument, 0, '\0' },
 106         { "consumerd64-libdir", required_argument, 0, '\0' },
 107         { "daemonize", no_argument, 0, 'd' },
 108         { "background", no_argument, 0, 'b' },
 109         { "sig-parent", no_argument, 0, 'S' },
 110         { "help", no_argument, 0, 'h' },
 111         { "group", required_argument, 0, 'g' },
 112         { "version", no_argument, 0, 'V' },
 113         { "quiet", no_argument, 0, 'q' },
 114         { "verbose", no_argument, 0, 'v' },
 115         { "verbose-consumer", no_argument, 0, '\0' },
 116         { "no-kernel", no_argument, 0, '\0' },
 117         { "pidfile", required_argument, 0, 'p' },
 118         { "agent-tcp-port", required_argument, 0, '\0' },
 119         { "config", required_argument, 0, 'f' },
 120         { "load", required_argument, 0, 'l' },
 121         { "kmod-probes", required_argument, 0, '\0' },
 122         { "extra-kmod-probes", required_argument, 0, '\0' },
 123         { NULL, 0, 0, 0 }
 124 };
 125
 126 /* Command line options to ignore from configuration file */
 127 static const char *config_ignore_options[] = { "help", "version", "config" };
 128
 129 /*
 130  * This pipe is used to inform the thread managing application communication
 131  * that a command is queued and ready to be processed.
 132  */
 133 static int apps_cmd_pipe[2] = { -1, -1 };
 134 static int apps_cmd_notify_pipe[2] = { -1, -1 };
 135
 136 /*
 137  * UST registration command queue. This queue is tied with a futex and uses a N
 138  * wakers / 1 waiter implemented and detailed in futex.c/.h
 139  *
 140  * The thread_registration_apps and thread_dispatch_ust_registration uses this
 141  * queue along with the wait/wake scheme. The thread_manage_apps receives down
 142  * the line new application socket and monitors it for any I/O error or clean
 143  * close that triggers an unregistration of the application.
 144  */
 145 static struct ust_cmd_queue ust_cmd_queue;
 146
 147 /*
 148  * Section name to look for in the daemon configuration file.
 149  */
 150 static const char * const config_section_name = "sessiond";
 151
 152 /* Am I root or not. Set to 1 if the daemon is running as root */
 153 static int is_root;
 154
 155 /*
 156  * Stop all threads by closing the thread quit pipe.
 157  */
 158 static void stop_threads(void)
 159 {
 160         int ret;
 161
 162         /* Stopping all threads */
 163         DBG("Terminating all threads");
 164         ret = sessiond_notify_quit_pipe();
 165         if (ret < 0) {
 166                 ERR("write error on thread quit pipe");
 167         }
 168 }
 169
 170 /*
 171  * Close every consumer sockets.
 172  */
 173 static void close_consumer_sockets(void)
 174 {
 175         int ret;
 176
 177         if (kconsumer_data.err_sock >= 0) {
 178                 ret = close(kconsumer_data.err_sock);
 179                 if (ret < 0) {
 180                         PERROR("kernel consumer err_sock close");
 181                 }
 182         }
 183         if (ustconsumer32_data.err_sock >= 0) {
 184                 ret = close(ustconsumer32_data.err_sock);
 185                 if (ret < 0) {
 186                         PERROR("UST consumerd32 err_sock close");
 187                 }
 188         }
 189         if (ustconsumer64_data.err_sock >= 0) {
 190                 ret = close(ustconsumer64_data.err_sock);
 191                 if (ret < 0) {
 192                         PERROR("UST consumerd64 err_sock close");
 193                 }
 194         }
 195         if (kconsumer_data.cmd_sock >= 0) {
 196                 ret = close(kconsumer_data.cmd_sock);
 197                 if (ret < 0) {
 198                         PERROR("kernel consumer cmd_sock close");
 199                 }
 200         }
 201         if (ustconsumer32_data.cmd_sock >= 0) {
 202                 ret = close(ustconsumer32_data.cmd_sock);
 203                 if (ret < 0) {
 204                         PERROR("UST consumerd32 cmd_sock close");
 205                 }
 206         }
 207         if (ustconsumer64_data.cmd_sock >= 0) {
 208                 ret = close(ustconsumer64_data.cmd_sock);
 209                 if (ret < 0) {
 210                         PERROR("UST consumerd64 cmd_sock close");
 211                 }
 212         }
 213         if (kconsumer_data.channel_monitor_pipe >= 0) {
 214                 ret = close(kconsumer_data.channel_monitor_pipe);
 215                 if (ret < 0) {
 216                         PERROR("kernel consumer channel monitor pipe close");
 217                 }
 218         }
 219         if (ustconsumer32_data.channel_monitor_pipe >= 0) {
 220                 ret = close(ustconsumer32_data.channel_monitor_pipe);
 221                 if (ret < 0) {
 222                         PERROR("UST consumerd32 channel monitor pipe close");
 223                 }
 224         }
 225         if (ustconsumer64_data.channel_monitor_pipe >= 0) {
 226                 ret = close(ustconsumer64_data.channel_monitor_pipe);
 227                 if (ret < 0) {
 228                         PERROR("UST consumerd64 channel monitor pipe close");
 229                 }
 230         }
 231 }
 232
 233 /*
 234  * Wait on consumer process termination.
 235  *
 236  * Need to be called with the consumer data lock held or from a context
 237  * ensuring no concurrent access to data (e.g: cleanup).
 238  */
 239 static void wait_consumer(struct consumer_data *consumer_data)
 240 {
 241         pid_t ret;
 242         int status;
 243
 244         if (consumer_data->pid <= 0) {
 245                 return;
 246         }
 247
 248         DBG("Waiting for complete teardown of consumerd (PID: %d)",
 249                         consumer_data->pid);
 250         ret = waitpid(consumer_data->pid, &status, 0);
 251         if (ret == -1) {
 252                 PERROR("consumerd waitpid pid: %d", consumer_data->pid)
 253         } else  if (!WIFEXITED(status)) {
 254                 ERR("consumerd termination with error: %d",
 255                                 WEXITSTATUS(ret));
 256         }
 257         consumer_data->pid = 0;
 258 }
 259
 260 /*
 261  * Cleanup the session daemon's data structures.
 262  */
 263 static void sessiond_cleanup(void)
 264 {
 265         int ret;
 266         struct ltt_session_list *session_list = session_get_list();
 267
 268         DBG("Cleanup sessiond");
 269
 270         /*
 271          * Close the thread quit pipe. It has already done its job,
 272          * since we are now called.
 273          */
 274         sessiond_close_quit_pipe();
 275         utils_close_pipe(apps_cmd_pipe);
 276         utils_close_pipe(apps_cmd_notify_pipe);
 277         utils_close_pipe(kernel_poll_pipe);
 278
 279         ret = remove(config.pid_file_path.value);
 280         if (ret < 0) {
 281                 PERROR("remove pidfile %s", config.pid_file_path.value);
 282         }
 283
 284         DBG("Removing sessiond and consumerd content of directory %s",
 285                 config.rundir.value);
 286
 287         /* sessiond */
 288         DBG("Removing %s", config.pid_file_path.value);
 289         (void) unlink(config.pid_file_path.value);
 290
 291         DBG("Removing %s", config.agent_port_file_path.value);
 292         (void) unlink(config.agent_port_file_path.value);
 293
 294         /* kconsumerd */
 295         DBG("Removing %s", kconsumer_data.err_unix_sock_path);
 296         (void) unlink(kconsumer_data.err_unix_sock_path);
 297
 298         DBG("Removing directory %s", config.kconsumerd_path.value);
 299         (void) rmdir(config.kconsumerd_path.value);
 300
 301         /* ust consumerd 32 */
 302         DBG("Removing %s", config.consumerd32_err_unix_sock_path.value);
 303         (void) unlink(config.consumerd32_err_unix_sock_path.value);
 304
 305         DBG("Removing directory %s", config.consumerd32_path.value);
 306         (void) rmdir(config.consumerd32_path.value);
 307
 308         /* ust consumerd 64 */
 309         DBG("Removing %s", config.consumerd64_err_unix_sock_path.value);
 310         (void) unlink(config.consumerd64_err_unix_sock_path.value);
 311
 312         DBG("Removing directory %s", config.consumerd64_path.value);
 313         (void) rmdir(config.consumerd64_path.value);
 314
 315         pthread_mutex_destroy(&session_list->lock);
 316
 317         DBG("Cleaning up all per-event notifier domain agents");
 318         agent_by_event_notifier_domain_ht_destroy();
 319
 320         DBG("Cleaning up all agent apps");
 321         agent_app_ht_clean();
 322         DBG("Closing all UST sockets");
 323         ust_app_clean_list();
 324         buffer_reg_destroy_registries();
 325
 326         close_consumer_sockets();
 327
 328         wait_consumer(&kconsumer_data);
 329         wait_consumer(&ustconsumer64_data);
 330         wait_consumer(&ustconsumer32_data);
 331
 332         if (is_root && !config.no_kernel) {
 333                 cleanup_kernel_tracer();
 334         }
 335
 336         /*
 337          * We do NOT rmdir rundir because there are other processes
 338          * using it, for instance lttng-relayd, which can start in
 339          * parallel with this teardown.
 340          */
 341 }
 342
 343 /*
 344  * Cleanup the daemon's option data structures.
 345  */
 346 static void sessiond_cleanup_options(void)
 347 {
 348         DBG("Cleaning up options");
 349
 350         sessiond_config_fini(&config);
 351
 352         run_as_destroy_worker();
 353 }
 354
 355 static int string_match(const char *str1, const char *str2)
 356 {
 357         return (str1 && str2) && !strcmp(str1, str2);
 358 }
 359
 360 /*
 361  * Take an option from the getopt output and set it in the right variable to be
 362  * used later.
 363  *
 364  * Return 0 on success else a negative value.
 365  */
 366 static int set_option(int opt, const char *arg, const char *optname)
 367 {
 368         int ret = 0;
 369
 370         if (string_match(optname, "client-sock") || opt == 'c') {
 371                 if (!arg || *arg == '\0') {
 372                         ret = -EINVAL;
 373                         goto end;
 374                 }
 375                 if (lttng_is_setuid_setgid()) {
 376                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 377                                 "-c, --client-sock");
 378                 } else {
 379                         config_string_set(&config.client_unix_sock_path,
 380                                         strdup(arg));
 381                         if (!config.client_unix_sock_path.value) {
 382                                 ret = -ENOMEM;
 383                                 PERROR("strdup");
 384                         }
 385                 }
 386         } else if (string_match(optname, "apps-sock") || opt == 'a') {
 387                 if (!arg || *arg == '\0') {
 388                         ret = -EINVAL;
 389                         goto end;
 390                 }
 391                 if (lttng_is_setuid_setgid()) {
 392                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 393                                 "-a, --apps-sock");
 394                 } else {
 395                         config_string_set(&config.apps_unix_sock_path,
 396                                         strdup(arg));
 397                         if (!config.apps_unix_sock_path.value) {
 398                                 ret = -ENOMEM;
 399                                 PERROR("strdup");
 400                         }
 401                 }
 402         } else if (string_match(optname, "daemonize") || opt == 'd') {
 403                 config.daemonize = true;
 404         } else if (string_match(optname, "background") || opt == 'b') {
 405                 config.background = true;
 406         } else if (string_match(optname, "group") || opt == 'g') {
 407                 if (!arg || *arg == '\0') {
 408                         ret = -EINVAL;
 409                         goto end;
 410                 }
 411                 if (lttng_is_setuid_setgid()) {
 412                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 413                                 "-g, --group");
 414                 } else {
 415                         config_string_set(&config.tracing_group_name,
 416                                         strdup(arg));
 417                         if (!config.tracing_group_name.value) {
 418                                 ret = -ENOMEM;
 419                                 PERROR("strdup");
 420                         }
 421                 }
 422         } else if (string_match(optname, "help") || opt == 'h') {
 423                 ret = utils_show_help(8, "lttng-sessiond", help_msg);
 424                 if (ret) {
 425                         ERR("Cannot show --help for `lttng-sessiond`");
 426                         perror("exec");
 427                 }
 428                 exit(ret ? EXIT_FAILURE : EXIT_SUCCESS);
 429         } else if (string_match(optname, "version") || opt == 'V') {
 430                 opt_print_version = 1;
 431         } else if (string_match(optname, "sig-parent") || opt == 'S') {
 432                 config.sig_parent = true;
 433         } else if (string_match(optname, "kconsumerd-err-sock")) {
 434                 if (!arg || *arg == '\0') {
 435                         ret = -EINVAL;
 436                         goto end;
 437                 }
 438                 if (lttng_is_setuid_setgid()) {
 439                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 440                                 "--kconsumerd-err-sock");
 441                 } else {
 442                         config_string_set(&config.kconsumerd_err_unix_sock_path,
 443                                         strdup(arg));
 444                         if (!config.kconsumerd_err_unix_sock_path.value) {
 445                                 ret = -ENOMEM;
 446                                 PERROR("strdup");
 447                         }
 448                 }
 449         } else if (string_match(optname, "kconsumerd-cmd-sock")) {
 450                 if (!arg || *arg == '\0') {
 451                         ret = -EINVAL;
 452                         goto end;
 453                 }
 454                 if (lttng_is_setuid_setgid()) {
 455                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 456                                 "--kconsumerd-cmd-sock");
 457                 } else {
 458                         config_string_set(&config.kconsumerd_cmd_unix_sock_path,
 459                                         strdup(arg));
 460                         if (!config.kconsumerd_cmd_unix_sock_path.value) {
 461                                 ret = -ENOMEM;
 462                                 PERROR("strdup");
 463                         }
 464                 }
 465         } else if (string_match(optname, "ustconsumerd64-err-sock")) {
 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                                 "--ustconsumerd64-err-sock");
 473                 } else {
 474                         config_string_set(&config.consumerd64_err_unix_sock_path,
 475                                         strdup(arg));
 476                         if (!config.consumerd64_err_unix_sock_path.value) {
 477                                 ret = -ENOMEM;
 478                                 PERROR("strdup");
 479                         }
 480                 }
 481         } else if (string_match(optname, "ustconsumerd64-cmd-sock")) {
 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                                 "--ustconsumerd64-cmd-sock");
 489                 } else {
 490                         config_string_set(&config.consumerd64_cmd_unix_sock_path,
 491                                         strdup(arg));
 492                         if (!config.consumerd64_cmd_unix_sock_path.value) {
 493                                 ret = -ENOMEM;
 494                                 PERROR("strdup");
 495                         }
 496                 }
 497         } else if (string_match(optname, "ustconsumerd32-err-sock")) {
 498                 if (!arg || *arg == '\0') {
 499                         ret = -EINVAL;
 500                         goto end;
 501                 }
 502                 if (lttng_is_setuid_setgid()) {
 503                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 504                                 "--ustconsumerd32-err-sock");
 505                 } else {
 506                         config_string_set(&config.consumerd32_err_unix_sock_path,
 507                                         strdup(arg));
 508                         if (!config.consumerd32_err_unix_sock_path.value) {
 509                                 ret = -ENOMEM;
 510                                 PERROR("strdup");
 511                         }
 512                 }
 513         } else if (string_match(optname, "ustconsumerd32-cmd-sock")) {
 514                 if (!arg || *arg == '\0') {
 515                         ret = -EINVAL;
 516                         goto end;
 517                 }
 518                 if (lttng_is_setuid_setgid()) {
 519                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 520                                 "--ustconsumerd32-cmd-sock");
 521                 } else {
 522                         config_string_set(&config.consumerd32_cmd_unix_sock_path,
 523                                         strdup(arg));
 524                         if (!config.consumerd32_cmd_unix_sock_path.value) {
 525                                 ret = -ENOMEM;
 526                                 PERROR("strdup");
 527                         }
 528                 }
 529         } else if (string_match(optname, "no-kernel")) {
 530                 config.no_kernel = true;
 531         } else if (string_match(optname, "quiet") || opt == 'q') {
 532                 config.quiet = true;
 533         } else if (string_match(optname, "verbose") || opt == 'v') {
 534                 /* Verbose level can increase using multiple -v */
 535                 if (arg) {
 536                         /* Value obtained from config file */
 537                         config.verbose = config_parse_value(arg);
 538                 } else {
 539                         /* -v used on command line */
 540                         config.verbose++;
 541                 }
 542                 /* Clamp value to [0, 3] */
 543                 config.verbose = config.verbose < 0 ? 0 :
 544                         (config.verbose <= 3 ? config.verbose : 3);
 545         } else if (string_match(optname, "verbose-consumer")) {
 546                 if (arg) {
 547                         config.verbose_consumer = config_parse_value(arg);
 548                 } else {
 549                         config.verbose_consumer++;
 550                 }
 551         } else if (string_match(optname, "consumerd32-path")) {
 552                 if (!arg || *arg == '\0') {
 553                         ret = -EINVAL;
 554                         goto end;
 555                 }
 556                 if (lttng_is_setuid_setgid()) {
 557                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 558                                 "--consumerd32-path");
 559                 } else {
 560                         config_string_set(&config.consumerd32_bin_path,
 561                                         strdup(arg));
 562                         if (!config.consumerd32_bin_path.value) {
 563                                 PERROR("strdup");
 564                                 ret = -ENOMEM;
 565                         }
 566                 }
 567         } else if (string_match(optname, "consumerd32-libdir")) {
 568                 if (!arg || *arg == '\0') {
 569                         ret = -EINVAL;
 570                         goto end;
 571                 }
 572                 if (lttng_is_setuid_setgid()) {
 573                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 574                                 "--consumerd32-libdir");
 575                 } else {
 576                         config_string_set(&config.consumerd32_lib_dir,
 577                                         strdup(arg));
 578                         if (!config.consumerd32_lib_dir.value) {
 579                                 PERROR("strdup");
 580                                 ret = -ENOMEM;
 581                         }
 582                 }
 583         } else if (string_match(optname, "consumerd64-path")) {
 584                 if (!arg || *arg == '\0') {
 585                         ret = -EINVAL;
 586                         goto end;
 587                 }
 588                 if (lttng_is_setuid_setgid()) {
 589                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 590                                 "--consumerd64-path");
 591                 } else {
 592                         config_string_set(&config.consumerd64_bin_path,
 593                                         strdup(arg));
 594                         if (!config.consumerd64_bin_path.value) {
 595                                 PERROR("strdup");
 596                                 ret = -ENOMEM;
 597                         }
 598                 }
 599         } else if (string_match(optname, "consumerd64-libdir")) {
 600                 if (!arg || *arg == '\0') {
 601                         ret = -EINVAL;
 602                         goto end;
 603                 }
 604                 if (lttng_is_setuid_setgid()) {
 605                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 606                                 "--consumerd64-libdir");
 607                 } else {
 608                         config_string_set(&config.consumerd64_lib_dir,
 609                                         strdup(arg));
 610                         if (!config.consumerd64_lib_dir.value) {
 611                                 PERROR("strdup");
 612                                 ret = -ENOMEM;
 613                         }
 614                 }
 615         } else if (string_match(optname, "pidfile") || opt == 'p') {
 616                 if (!arg || *arg == '\0') {
 617                         ret = -EINVAL;
 618                         goto end;
 619                 }
 620                 if (lttng_is_setuid_setgid()) {
 621                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 622                                 "-p, --pidfile");
 623                 } else {
 624                         config_string_set(&config.pid_file_path, strdup(arg));
 625                         if (!config.pid_file_path.value) {
 626                                 PERROR("strdup");
 627                                 ret = -ENOMEM;
 628                         }
 629                 }
 630         } else if (string_match(optname, "agent-tcp-port")) {
 631                 if (!arg || *arg == '\0') {
 632                         ret = -EINVAL;
 633                         goto end;
 634                 }
 635                 if (lttng_is_setuid_setgid()) {
 636                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 637                                 "--agent-tcp-port");
 638                 } else {
 639                         unsigned long v;
 640
 641                         errno = 0;
 642                         v = strtoul(arg, NULL, 0);
 643                         if (errno != 0 || !isdigit(arg[0])) {
 644                                 ERR("Wrong value in --agent-tcp-port parameter: %s", arg);
 645                                 return -1;
 646                         }
 647                         if (v == 0 || v >= 65535) {
 648                                 ERR("Port overflow in --agent-tcp-port parameter: %s", arg);
 649                                 return -1;
 650                         }
 651                         config.agent_tcp_port.begin = config.agent_tcp_port.end = (int) v;
 652                         DBG3("Agent TCP port set to non default: %i", (int) v);
 653                 }
 654         } else if (string_match(optname, "load") || opt == 'l') {
 655                 if (!arg || *arg == '\0') {
 656                         ret = -EINVAL;
 657                         goto end;
 658                 }
 659                 if (lttng_is_setuid_setgid()) {
 660                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 661                                 "-l, --load");
 662                 } else {
 663                         config_string_set(&config.load_session_path, strdup(arg));
 664                         if (!config.load_session_path.value) {
 665                                 PERROR("strdup");
 666                                 ret = -ENOMEM;
 667                         }
 668                 }
 669         } else if (string_match(optname, "kmod-probes")) {
 670                 if (!arg || *arg == '\0') {
 671                         ret = -EINVAL;
 672                         goto end;
 673                 }
 674                 if (lttng_is_setuid_setgid()) {
 675                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 676                                 "--kmod-probes");
 677                 } else {
 678                         config_string_set(&config.kmod_probes_list, strdup(arg));
 679                         if (!config.kmod_probes_list.value) {
 680                                 PERROR("strdup");
 681                                 ret = -ENOMEM;
 682                         }
 683                 }
 684         } else if (string_match(optname, "extra-kmod-probes")) {
 685                 if (!arg || *arg == '\0') {
 686                         ret = -EINVAL;
 687                         goto end;
 688                 }
 689                 if (lttng_is_setuid_setgid()) {
 690                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 691                                 "--extra-kmod-probes");
 692                 } else {
 693                         config_string_set(&config.kmod_extra_probes_list,
 694                                         strdup(arg));
 695                         if (!config.kmod_extra_probes_list.value) {
 696                                 PERROR("strdup");
 697                                 ret = -ENOMEM;
 698                         }
 699                 }
 700         } else if (string_match(optname, "config") || opt == 'f') {
 701                 /* This is handled in set_options() thus silent skip. */
 702                 goto end;
 703         } else {
 704                 /* Unknown option or other error.
 705                  * Error is printed by getopt, just return */
 706                 ret = -1;
 707         }
 708
 709 end:
 710         if (ret == -EINVAL) {
 711                 const char *opt_name = "unknown";
 712                 int i;
 713
 714                 for (i = 0; i < sizeof(long_options) / sizeof(struct option);
 715                         i++) {
 716                         if (opt == long_options[i].val) {
 717                                 opt_name = long_options[i].name;
 718                                 break;
 719                         }
 720                 }
 721
 722                 WARN("Invalid argument provided for option \"%s\", using default value.",
 723                         opt_name);
 724         }
 725
 726         return ret;
 727 }
 728
 729 /*
 730  * config_entry_handler_cb used to handle options read from a config file.
 731  * See config_entry_handler_cb comment in common/config/session-config.h for the
 732  * return value conventions.
 733  */
 734 static int config_entry_handler(const struct config_entry *entry, void *unused)
 735 {
 736         int ret = 0, i;
 737
 738         if (!entry || !entry->name || !entry->value) {
 739                 ret = -EINVAL;
 740                 goto end;
 741         }
 742
 743         /* Check if the option is to be ignored */
 744         for (i = 0; i < sizeof(config_ignore_options) / sizeof(char *); i++) {
 745                 if (!strcmp(entry->name, config_ignore_options[i])) {
 746                         goto end;
 747                 }
 748         }
 749
 750         for (i = 0; i < (sizeof(long_options) / sizeof(struct option)) - 1;
 751                 i++) {
 752
 753                 /* Ignore if not fully matched. */
 754                 if (strcmp(entry->name, long_options[i].name)) {
 755                         continue;
 756                 }
 757
 758                 /*
 759                  * If the option takes no argument on the command line, we have to
 760                  * check if the value is "true". We support non-zero numeric values,
 761                  * true, on and yes.
 762                  */
 763                 if (!long_options[i].has_arg) {
 764                         ret = config_parse_value(entry->value);
 765                         if (ret <= 0) {
 766                                 if (ret) {
 767                                         WARN("Invalid configuration value \"%s\" for option %s",
 768                                                         entry->value, entry->name);
 769                                 }
 770                                 /* False, skip boolean config option. */
 771                                 goto end;
 772                         }
 773                 }
 774
 775                 ret = set_option(long_options[i].val, entry->value, entry->name);
 776                 goto end;
 777         }
 778
 779         WARN("Unrecognized option \"%s\" in daemon configuration file.", entry->name);
 780
 781 end:
 782         return ret;
 783 }
 784
 785 static void print_version(void) {
 786         fprintf(stdout, "%s\n", VERSION);
 787 }
 788
 789 /*
 790  * daemon configuration loading and argument parsing
 791  */
 792 static int set_options(int argc, char **argv)
 793 {
 794         int ret = 0, c = 0, option_index = 0;
 795         int orig_optopt = optopt, orig_optind = optind;
 796         char *optstring;
 797         const char *config_path = NULL;
 798
 799         optstring = utils_generate_optstring(long_options,
 800                         sizeof(long_options) / sizeof(struct option));
 801         if (!optstring) {
 802                 ret = -ENOMEM;
 803                 goto end;
 804         }
 805
 806         /* Check for the --config option */
 807         while ((c = getopt_long(argc, argv, optstring, long_options,
 808                                         &option_index)) != -1) {
 809                 if (c == '?') {
 810                         ret = -EINVAL;
 811                         goto end;
 812                 } else if (c != 'f') {
 813                         /* if not equal to --config option. */
 814                         continue;
 815                 }
 816
 817                 if (lttng_is_setuid_setgid()) {
 818                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 819                                 "-f, --config");
 820                 } else {
 821                         config_path = utils_expand_path(optarg);
 822                         if (!config_path) {
 823                                 ERR("Failed to resolve path: %s", optarg);
 824                         }
 825                 }
 826         }
 827
 828         ret = config_get_section_entries(config_path, config_section_name,
 829                         config_entry_handler, NULL);
 830         if (ret) {
 831                 if (ret > 0) {
 832                         ERR("Invalid configuration option at line %i", ret);
 833                         ret = -1;
 834                 }
 835                 goto end;
 836         }
 837
 838         /* Reset getopt's global state */
 839         optopt = orig_optopt;
 840         optind = orig_optind;
 841         while (1) {
 842                 option_index = -1;
 843                 /*
 844                  * getopt_long() will not set option_index if it encounters a
 845                  * short option.
 846                  */
 847                 c = getopt_long(argc, argv, optstring, long_options,
 848                                 &option_index);
 849                 if (c == -1) {
 850                         break;
 851                 }
 852
 853                 /*
 854                  * Pass NULL as the long option name if popt left the index
 855                  * unset.
 856                  */
 857                 ret = set_option(c, optarg,
 858                                 option_index < 0 ? NULL :
 859                                 long_options[option_index].name);
 860                 if (ret < 0) {
 861                         break;
 862                 }
 863         }
 864
 865 end:
 866         free(optstring);
 867         return ret;
 868 }
 869
 870 /*
 871  * Create lockfile using the rundir and return its fd.
 872  */
 873 static int create_lockfile(void)
 874 {
 875         return utils_create_lock_file(config.lock_file_path.value);
 876 }
 877
 878 /*
 879  * Check if the global socket is available, and if a daemon is answering at the
 880  * other side. If yes, error is returned.
 881  *
 882  * Also attempts to create and hold the lock file.
 883  */
 884 static int check_existing_daemon(void)
 885 {
 886         int ret = 0;
 887
 888         /* Is there anybody out there ? */
 889         if (lttng_session_daemon_alive()) {
 890                 ret = -EEXIST;
 891                 goto end;
 892         }
 893
 894         lockfile_fd = create_lockfile();
 895         if (lockfile_fd < 0) {
 896                 ret = -EEXIST;
 897                 goto end;
 898         }
 899 end:
 900         return ret;
 901 }
 902
 903 static void sessiond_cleanup_lock_file(void)
 904 {
 905         int ret;
 906
 907         /*
 908          * Cleanup lock file by deleting it and finaly closing it which will
 909          * release the file system lock.
 910          */
 911         if (lockfile_fd >= 0) {
 912                 ret = remove(config.lock_file_path.value);
 913                 if (ret < 0) {
 914                         PERROR("remove lock file");
 915                 }
 916                 ret = close(lockfile_fd);
 917                 if (ret < 0) {
 918                         PERROR("close lock file");
 919                 }
 920         }
 921 }
 922
 923 /*
 924  * Set the tracing group gid onto the client socket.
 925  *
 926  * Race window between mkdir and chown is OK because we are going from more
 927  * permissive (root.root) to less permissive (root.tracing).
 928  */
 929 static int set_permissions(char *rundir)
 930 {
 931         int ret;
 932         gid_t gid;
 933
 934         ret = utils_get_group_id(config.tracing_group_name.value, true, &gid);
 935         if (ret) {
 936                 /* Default to root group. */
 937                 gid = 0;
 938         }
 939
 940         /* Set lttng run dir */
 941         ret = chown(rundir, 0, gid);
 942         if (ret < 0) {
 943                 ERR("Unable to set group on %s", rundir);
 944                 PERROR("chown");
 945         }
 946
 947         /*
 948          * Ensure all applications and tracing group can search the run
 949          * dir. Allow everyone to read the directory, since it does not
 950          * buy us anything to hide its content.
 951          */
 952         ret = chmod(rundir, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH);
 953         if (ret < 0) {
 954                 ERR("Unable to set permissions on %s", rundir);
 955                 PERROR("chmod");
 956         }
 957
 958         /* lttng client socket path */
 959         ret = chown(config.client_unix_sock_path.value, 0, gid);
 960         if (ret < 0) {
 961                 ERR("Unable to set group on %s", config.client_unix_sock_path.value);
 962                 PERROR("chown");
 963         }
 964
 965         /* kconsumer error socket path */
 966         ret = chown(kconsumer_data.err_unix_sock_path, 0, 0);
 967         if (ret < 0) {
 968                 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
 969                 PERROR("chown");
 970         }
 971
 972         /* 64-bit ustconsumer error socket path */
 973         ret = chown(ustconsumer64_data.err_unix_sock_path, 0, 0);
 974         if (ret < 0) {
 975                 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
 976                 PERROR("chown");
 977         }
 978
 979         /* 32-bit ustconsumer compat32 error socket path */
 980         ret = chown(ustconsumer32_data.err_unix_sock_path, 0, 0);
 981         if (ret < 0) {
 982                 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
 983                 PERROR("chown");
 984         }
 985
 986         DBG("All permissions are set");
 987
 988         return ret;
 989 }
 990
 991 /*
 992  * Create the lttng run directory needed for all global sockets and pipe.
 993  */
 994 static int create_lttng_rundir(void)
 995 {
 996         int ret;
 997
 998         DBG3("Creating LTTng run directory: %s", config.rundir.value);
 999
1000         ret = mkdir(config.rundir.value, S_IRWXU);
1001         if (ret < 0) {
1002                 if (errno != EEXIST) {
1003                         ERR("Unable to create %s", config.rundir.value);
1004                         goto error;
1005                 } else {
1006                         ret = 0;
1007                 }
1008         }
1009
1010 error:
1011         return ret;
1012 }
1013
1014 /*
1015  * Setup sockets and directory needed by the consumerds' communication with the
1016  * session daemon.
1017  */
1018 static int set_consumer_sockets(struct consumer_data *consumer_data)
1019 {
1020         int ret;
1021         char *path = NULL;
1022
1023         switch (consumer_data->type) {
1024         case LTTNG_CONSUMER_KERNEL:
1025                 path = config.kconsumerd_path.value;
1026                 break;
1027         case LTTNG_CONSUMER64_UST:
1028                 path = config.consumerd64_path.value;
1029                 break;
1030         case LTTNG_CONSUMER32_UST:
1031                 path = config.consumerd32_path.value;
1032                 break;
1033         default:
1034                 ERR("Consumer type unknown");
1035                 ret = -EINVAL;
1036                 goto error;
1037         }
1038         assert(path);
1039
1040         DBG2("Creating consumer directory: %s", path);
1041
1042         ret = mkdir(path, S_IRWXU | S_IRGRP | S_IXGRP);
1043         if (ret < 0 && errno != EEXIST) {
1044                 PERROR("mkdir");
1045                 ERR("Failed to create %s", path);
1046                 goto error;
1047         }
1048         if (is_root) {
1049                 gid_t gid;
1050
1051                 ret = utils_get_group_id(config.tracing_group_name.value, true,
1052                                 &gid);
1053                 if (ret) {
1054                         /* Default to root group. */
1055                         gid = 0;
1056                 }
1057
1058                 ret = chown(path, 0, gid);
1059                 if (ret < 0) {
1060                         ERR("Unable to set group on %s", path);
1061                         PERROR("chown");
1062                         goto error;
1063                 }
1064         }
1065
1066         /* Create the consumerd error unix socket */
1067         consumer_data->err_sock =
1068                 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
1069         if (consumer_data->err_sock < 0) {
1070                 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
1071                 ret = -1;
1072                 goto error;
1073         }
1074
1075         /*
1076          * Set the CLOEXEC flag. Return code is useless because either way, the
1077          * show must go on.
1078          */
1079         ret = utils_set_fd_cloexec(consumer_data->err_sock);
1080         if (ret < 0) {
1081                 PERROR("utils_set_fd_cloexec");
1082                 /* continue anyway */
1083         }
1084
1085         /* File permission MUST be 660 */
1086         ret = chmod(consumer_data->err_unix_sock_path,
1087                         S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
1088         if (ret < 0) {
1089                 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
1090                 PERROR("chmod");
1091                 goto error;
1092         }
1093
1094 error:
1095         return ret;
1096 }
1097
1098 /*
1099  * Signal handler for the daemon
1100  *
1101  * Simply stop all worker threads, leaving main() return gracefully after
1102  * joining all threads and calling cleanup().
1103  */
1104 static void sighandler(int sig)
1105 {
1106         switch (sig) {
1107         case SIGINT:
1108                 DBG("SIGINT caught");
1109                 stop_threads();
1110                 break;
1111         case SIGTERM:
1112                 DBG("SIGTERM caught");
1113                 stop_threads();
1114                 break;
1115         case SIGUSR1:
1116                 CMM_STORE_SHARED(recv_child_signal, 1);
1117                 break;
1118         default:
1119                 break;
1120         }
1121 }
1122
1123 /*
1124  * Setup signal handler for :
1125  *              SIGINT, SIGTERM, SIGPIPE
1126  */
1127 static int set_signal_handler(void)
1128 {
1129         int ret = 0;
1130         struct sigaction sa;
1131         sigset_t sigset;
1132
1133         if ((ret = sigemptyset(&sigset)) < 0) {
1134                 PERROR("sigemptyset");
1135                 return ret;
1136         }
1137
1138         sa.sa_mask = sigset;
1139         sa.sa_flags = 0;
1140
1141         sa.sa_handler = sighandler;
1142         if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
1143                 PERROR("sigaction");
1144                 return ret;
1145         }
1146
1147         if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
1148                 PERROR("sigaction");
1149                 return ret;
1150         }
1151
1152         if ((ret = sigaction(SIGUSR1, &sa, NULL)) < 0) {
1153                 PERROR("sigaction");
1154                 return ret;
1155         }
1156
1157         sa.sa_handler = SIG_IGN;
1158         if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
1159                 PERROR("sigaction");
1160                 return ret;
1161         }
1162
1163         DBG("Signal handler set for SIGTERM, SIGUSR1, SIGPIPE and SIGINT");
1164
1165         return ret;
1166 }
1167
1168 /*
1169  * Set open files limit to unlimited. This daemon can open a large number of
1170  * file descriptors in order to consume multiple kernel traces.
1171  */
1172 static void set_ulimit(void)
1173 {
1174         int ret;
1175         struct rlimit lim;
1176
1177         /* The kernel does not allow an infinite limit for open files */
1178         lim.rlim_cur = 65535;
1179         lim.rlim_max = 65535;
1180
1181         ret = setrlimit(RLIMIT_NOFILE, &lim);
1182         if (ret < 0) {
1183                 PERROR("failed to set open files limit");
1184         }
1185 }
1186
1187 static int write_pidfile(void)
1188 {
1189         return utils_create_pid_file(getpid(), config.pid_file_path.value);
1190 }
1191
1192 static int set_clock_plugin_env(void)
1193 {
1194         int ret = 0;
1195         char *env_value = NULL;
1196
1197         if (!config.lttng_ust_clock_plugin.value) {
1198                 goto end;
1199         }
1200
1201         ret = asprintf(&env_value, "LTTNG_UST_CLOCK_PLUGIN=%s",
1202                         config.lttng_ust_clock_plugin.value);
1203         if (ret < 0) {
1204                 PERROR("asprintf");
1205                 goto end;
1206         }
1207
1208         ret = putenv(env_value);
1209         if (ret) {
1210                 free(env_value);
1211                 PERROR("putenv of LTTNG_UST_CLOCK_PLUGIN");
1212                 goto end;
1213         }
1214
1215         DBG("Updated LTTNG_UST_CLOCK_PLUGIN environment variable to \"%s\"",
1216                         config.lttng_ust_clock_plugin.value);
1217 end:
1218         return ret;
1219 }
1220
1221 static void destroy_all_sessions_and_wait(void)
1222 {
1223         struct ltt_session *session, *tmp;
1224         struct ltt_session_list *session_list;
1225
1226         session_list = session_get_list();
1227         DBG("Initiating destruction of all sessions");
1228
1229         if (!session_list) {
1230                 return;
1231         }
1232
1233         session_lock_list();
1234         /* Initiate the destruction of all sessions. */
1235         cds_list_for_each_entry_safe(session, tmp,
1236                         &session_list->head, list) {
1237                 if (!session_get(session)) {
1238                         continue;
1239                 }
1240
1241                 session_lock(session);
1242                 if (session->destroyed) {
1243                         goto unlock_session;
1244                 }
1245                 (void) cmd_stop_trace(session);
1246                 (void) cmd_destroy_session(session, notification_thread_handle,
1247                                 NULL);
1248         unlock_session:
1249                 session_unlock(session);
1250                 session_put(session);
1251         }
1252         session_unlock_list();
1253
1254         /* Wait for the destruction of all sessions to complete. */
1255         DBG("Waiting for the destruction of all sessions to complete");
1256         session_list_wait_empty();
1257         DBG("Destruction of all sessions completed");
1258 }
1259
1260 static void unregister_all_triggers(void)
1261 {
1262         enum lttng_error_code ret_code;
1263         enum lttng_trigger_status trigger_status;
1264         struct lttng_triggers *triggers = NULL;
1265         unsigned int trigger_count, i;
1266         const struct lttng_credentials creds = {
1267                         .uid = LTTNG_OPTIONAL_INIT_VALUE(0),
1268         };
1269
1270         DBG("Unregistering all triggers");
1271
1272         /*
1273          * List all triggers as "root" since we wish to unregister all triggers.
1274          */
1275         ret_code = notification_thread_command_list_triggers(
1276                         notification_thread_handle, creds.uid.value, &triggers);
1277         if (ret_code != LTTNG_OK) {
1278                 ERR("Failed to list triggers while unregistering all triggers");
1279                 goto end;
1280         }
1281
1282         trigger_status = lttng_triggers_get_count(triggers, &trigger_count);
1283         assert(trigger_status == LTTNG_TRIGGER_STATUS_OK);
1284
1285         for (i = 0; i < trigger_count; i++) {
1286                 enum lttng_error_code ret_code;
1287                 uid_t trigger_owner;
1288                 const char *trigger_name;
1289                 const struct lttng_trigger *trigger =
1290                                 lttng_triggers_get_at_index(triggers, i);
1291
1292                 assert(trigger);
1293
1294                 trigger_status = lttng_trigger_get_owner_uid(
1295                                 trigger, &trigger_owner);
1296                 assert(trigger_status == LTTNG_TRIGGER_STATUS_OK);
1297
1298                 trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
1299                 assert(trigger_status == LTTNG_TRIGGER_STATUS_OK);
1300
1301                 DBG("Unregistering trigger: trigger owner uid = %d, trigger name = '%s'",
1302                                 (int) trigger_owner, trigger_name);
1303
1304                 ret_code = cmd_unregister_trigger(
1305                                 &creds, trigger, notification_thread_handle);
1306                 if (ret_code != LTTNG_OK) {
1307                         ERR("Failed to unregister trigger: trigger owner uid = %d, trigger name = '%s', error: '%s'",
1308                                         (int) trigger_owner, trigger_name,
1309                                         lttng_strerror(-ret_code));
1310                         /* Continue to unregister the remaining triggers. */
1311                 }
1312         }
1313 end:
1314         lttng_triggers_destroy(triggers);
1315 }
1316
1317 static int run_as_worker_post_fork_cleanup(void *data)
1318 {
1319         struct sessiond_config *sessiond_config = data;
1320
1321         sessiond_config_fini(sessiond_config);
1322         return 0;
1323 }
1324
1325 static int launch_run_as_worker(const char *procname)
1326 {
1327         /*
1328          * Clean-up before forking the run-as worker. Any dynamically
1329          * allocated memory of which the worker is not aware will
1330          * be leaked as the process forks a run-as worker (and performs
1331          * no exec*()). The same would apply to any opened fd.
1332          */
1333         return run_as_create_worker(procname, run_as_worker_post_fork_cleanup,
1334                         &config);
1335 }
1336
1337 static void sessiond_uuid_log(void)
1338 {
1339         char uuid_str[LTTNG_UUID_STR_LEN];
1340
1341         lttng_uuid_to_str(sessiond_uuid, uuid_str);
1342         DBG("Starting lttng-sessiond {%s}", uuid_str);
1343 }
1344
1345 /*
1346  * main
1347  */
1348 int main(int argc, char **argv)
1349 {
1350         int ret = 0, retval = 0;
1351         const char *env_app_timeout;
1352         struct lttng_pipe *ust32_channel_monitor_pipe = NULL,
1353                         *ust64_channel_monitor_pipe = NULL,
1354                         *kernel_channel_monitor_pipe = NULL;
1355         struct lttng_thread *ht_cleanup_thread = NULL;
1356         struct timer_thread_parameters timer_thread_parameters;
1357         /* Rotation thread handle. */
1358         struct rotation_thread_handle *rotation_thread_handle = NULL;
1359         /* Queue of rotation jobs populated by the sessiond-timer. */
1360         struct rotation_thread_timer_queue *rotation_timer_queue = NULL;
1361         struct lttng_thread *client_thread = NULL;
1362         struct lttng_thread *notification_thread = NULL;
1363         struct lttng_thread *register_apps_thread = NULL;
1364
1365         logger_set_thread_name("Main", false);
1366         init_kernel_workarounds();
1367
1368         rcu_register_thread();
1369
1370         if (set_signal_handler()) {
1371                 retval = -1;
1372                 goto exit_set_signal_handler;
1373         }
1374
1375         if (timer_signal_init()) {
1376                 retval = -1;
1377                 goto exit_set_signal_handler;
1378         }
1379
1380         page_size = sysconf(_SC_PAGESIZE);
1381         if (page_size < 0) {
1382                 PERROR("sysconf _SC_PAGESIZE");
1383                 page_size = LONG_MAX;
1384                 WARN("Fallback page size to %ld", page_size);
1385         }
1386
1387         ret = sessiond_config_init(&config);
1388         if (ret) {
1389                 retval = -1;
1390                 goto exit_set_signal_handler;
1391         }
1392
1393         /*
1394          * Init config from environment variables.
1395          * Command line option override env configuration per-doc. Do env first.
1396          */
1397         sessiond_config_apply_env_config(&config);
1398
1399         /*
1400          * Parse arguments and load the daemon configuration file.
1401          *
1402          * We have an exit_options exit path to free memory reserved by
1403          * set_options. This is needed because the rest of sessiond_cleanup()
1404          * depends on ht_cleanup_thread, which depends on lttng_daemonize, which
1405          * depends on set_options.
1406          */
1407         progname = argv[0];
1408         if (set_options(argc, argv)) {
1409                 retval = -1;
1410                 goto exit_options;
1411         }
1412
1413         /*
1414          * Resolve all paths received as arguments, configuration option, or
1415          * through environment variable as absolute paths. This is necessary
1416          * since daemonizing causes the sessiond's current working directory
1417          * to '/'.
1418          */
1419         ret = sessiond_config_resolve_paths(&config);
1420         if (ret) {
1421                 goto exit_options;
1422         }
1423
1424         /* Apply config. */
1425         lttng_opt_verbose = config.verbose;
1426         lttng_opt_quiet = config.quiet;
1427         kconsumer_data.err_unix_sock_path =
1428                         config.kconsumerd_err_unix_sock_path.value;
1429         kconsumer_data.cmd_unix_sock_path =
1430                         config.kconsumerd_cmd_unix_sock_path.value;
1431         ustconsumer32_data.err_unix_sock_path =
1432                         config.consumerd32_err_unix_sock_path.value;
1433         ustconsumer32_data.cmd_unix_sock_path =
1434                         config.consumerd32_cmd_unix_sock_path.value;
1435         ustconsumer64_data.err_unix_sock_path =
1436                         config.consumerd64_err_unix_sock_path.value;
1437         ustconsumer64_data.cmd_unix_sock_path =
1438                         config.consumerd64_cmd_unix_sock_path.value;
1439         set_clock_plugin_env();
1440
1441         sessiond_config_log(&config);
1442         sessiond_uuid_log();
1443
1444         if (opt_print_version) {
1445                 print_version();
1446                 retval = 0;
1447                 goto exit_options;
1448         }
1449
1450         if (create_lttng_rundir()) {
1451                 retval = -1;
1452                 goto exit_options;
1453         }
1454
1455         /* Abort launch if a session daemon is already running. */
1456         if (check_existing_daemon()) {
1457                 ERR("A session daemon is already running.");
1458                 retval = -1;
1459                 goto exit_options;
1460         }
1461
1462         /* Daemonize */
1463         if (config.daemonize || config.background) {
1464                 int i;
1465
1466                 ret = lttng_daemonize(&child_ppid, &recv_child_signal,
1467                         !config.background);
1468                 if (ret < 0) {
1469                         retval = -1;
1470                         goto exit_options;
1471                 }
1472
1473                 /*
1474                  * We are in the child. Make sure all other file descriptors are
1475                  * closed, in case we are called with more opened file
1476                  * descriptors than the standard ones and the lock file.
1477                  */
1478                 for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
1479                         if (i == lockfile_fd) {
1480                                 continue;
1481                         }
1482                         (void) close(i);
1483                 }
1484         }
1485
1486         if (launch_run_as_worker(argv[0]) < 0) {
1487                 goto exit_create_run_as_worker_cleanup;
1488         }
1489
1490         /*
1491          * Starting from here, we can create threads. This needs to be after
1492          * lttng_daemonize due to RCU.
1493          */
1494
1495         /*
1496          * Initialize the health check subsystem. This call should set the
1497          * appropriate time values.
1498          */
1499         health_sessiond = health_app_create(NR_HEALTH_SESSIOND_TYPES);
1500         if (!health_sessiond) {
1501                 PERROR("health_app_create error");
1502                 retval = -1;
1503                 goto stop_threads;
1504         }
1505
1506         /* Create thread to clean up RCU hash tables */
1507         ht_cleanup_thread = launch_ht_cleanup_thread();
1508         if (!ht_cleanup_thread) {
1509                 retval = -1;
1510                 goto stop_threads;
1511         }
1512
1513         /* Create thread quit pipe */
1514         if (sessiond_init_thread_quit_pipe()) {
1515                 retval = -1;
1516                 goto stop_threads;
1517         }
1518
1519         /* Check if daemon is UID = 0 */
1520         is_root = !getuid();
1521         if (is_root) {
1522                 /* Create global run dir with root access */
1523
1524                 kernel_channel_monitor_pipe = lttng_pipe_open(0);
1525                 if (!kernel_channel_monitor_pipe) {
1526                         ERR("Failed to create kernel consumer channel monitor pipe");
1527                         retval = -1;
1528                         goto stop_threads;
1529                 }
1530                 kconsumer_data.channel_monitor_pipe =
1531                                 lttng_pipe_release_writefd(
1532                                         kernel_channel_monitor_pipe);
1533                 if (kconsumer_data.channel_monitor_pipe < 0) {
1534                         retval = -1;
1535                         goto stop_threads;
1536                 }
1537         }
1538
1539         /* Set consumer initial state */
1540         kernel_consumerd_state = CONSUMER_STOPPED;
1541         ust_consumerd_state = CONSUMER_STOPPED;
1542
1543         ust32_channel_monitor_pipe = lttng_pipe_open(0);
1544         if (!ust32_channel_monitor_pipe) {
1545                 ERR("Failed to create 32-bit user space consumer channel monitor pipe");
1546                 retval = -1;
1547                 goto stop_threads;
1548         }
1549         ustconsumer32_data.channel_monitor_pipe = lttng_pipe_release_writefd(
1550                         ust32_channel_monitor_pipe);
1551         if (ustconsumer32_data.channel_monitor_pipe < 0) {
1552                 retval = -1;
1553                 goto stop_threads;
1554         }
1555
1556         /*
1557          * The rotation_thread_timer_queue structure is shared between the
1558          * sessiond timer thread and the rotation thread. The main thread keeps
1559          * its ownership and destroys it when both threads have been joined.
1560          */
1561         rotation_timer_queue = rotation_thread_timer_queue_create();
1562         if (!rotation_timer_queue) {
1563                 retval = -1;
1564                 goto stop_threads;
1565         }
1566         timer_thread_parameters.rotation_thread_job_queue =
1567                         rotation_timer_queue;
1568
1569         ust64_channel_monitor_pipe = lttng_pipe_open(0);
1570         if (!ust64_channel_monitor_pipe) {
1571                 ERR("Failed to create 64-bit user space consumer channel monitor pipe");
1572                 retval = -1;
1573                 goto stop_threads;
1574         }
1575         ustconsumer64_data.channel_monitor_pipe = lttng_pipe_release_writefd(
1576                         ust64_channel_monitor_pipe);
1577         if (ustconsumer64_data.channel_monitor_pipe < 0) {
1578                 retval = -1;
1579                 goto stop_threads;
1580         }
1581
1582         /*
1583          * Init UST app hash table. Alloc hash table before this point since
1584          * cleanup() can get called after that point.
1585          */
1586         if (ust_app_ht_alloc()) {
1587                 ERR("Failed to allocate UST app hash table");
1588                 retval = -1;
1589                 goto stop_threads;
1590         }
1591
1592         /*
1593          * Initialize agent app hash table. We allocate the hash table here
1594          * since cleanup() can get called after this point.
1595          */
1596         if (agent_app_ht_alloc()) {
1597                 ERR("Failed to allocate Agent app hash table");
1598                 retval = -1;
1599                 goto stop_threads;
1600         }
1601
1602         if (agent_by_event_notifier_domain_ht_create()) {
1603                 ERR("Failed to allocate per-event notifier domain agent hash table");
1604                 retval = -1;
1605                 goto stop_threads;
1606         }
1607         /*
1608          * These actions must be executed as root. We do that *after* setting up
1609          * the sockets path because we MUST make the check for another daemon using
1610          * those paths *before* trying to set the kernel consumer sockets and init
1611          * kernel tracer.
1612          */
1613         if (is_root) {
1614                 if (set_consumer_sockets(&kconsumer_data)) {
1615                         retval = -1;
1616                         goto stop_threads;
1617                 }
1618
1619                 /* Setup kernel tracer */
1620                 if (!config.no_kernel) {
1621                         init_kernel_tracer();
1622                 }
1623
1624                 /* Set ulimit for open files */
1625                 set_ulimit();
1626         }
1627         /* init lttng_fd tracking must be done after set_ulimit. */
1628         lttng_fd_init();
1629
1630         if (set_consumer_sockets(&ustconsumer64_data)) {
1631                 retval = -1;
1632                 goto stop_threads;
1633         }
1634
1635         if (set_consumer_sockets(&ustconsumer32_data)) {
1636                 retval = -1;
1637                 goto stop_threads;
1638         }
1639
1640         /* Get parent pid if -S, --sig-parent is specified. */
1641         if (config.sig_parent) {
1642                 ppid = getppid();
1643         }
1644
1645         /* Setup the kernel pipe for waking up the kernel thread */
1646         if (is_root && !config.no_kernel) {
1647                 if (utils_create_pipe_cloexec(kernel_poll_pipe)) {
1648                         retval = -1;
1649                         goto stop_threads;
1650                 }
1651         }
1652
1653         /* Setup the thread apps communication pipe. */
1654         if (utils_create_pipe_cloexec(apps_cmd_pipe)) {
1655                 retval = -1;
1656                 goto stop_threads;
1657         }
1658
1659         /* Setup the thread apps notify communication pipe. */
1660         if (utils_create_pipe_cloexec(apps_cmd_notify_pipe)) {
1661                 retval = -1;
1662                 goto stop_threads;
1663         }
1664
1665         /* Initialize global buffer per UID and PID registry. */
1666         buffer_reg_init_uid_registry();
1667         buffer_reg_init_pid_registry();
1668
1669         /* Init UST command queue. */
1670         cds_wfcq_init(&ust_cmd_queue.head, &ust_cmd_queue.tail);
1671
1672         cmd_init();
1673
1674         /* Check for the application socket timeout env variable. */
1675         env_app_timeout = getenv(DEFAULT_APP_SOCKET_TIMEOUT_ENV);
1676         if (env_app_timeout) {
1677                 config.app_socket_timeout = atoi(env_app_timeout);
1678         } else {
1679                 config.app_socket_timeout = DEFAULT_APP_SOCKET_RW_TIMEOUT;
1680         }
1681
1682         ret = write_pidfile();
1683         if (ret) {
1684                 ERR("Error in write_pidfile");
1685                 retval = -1;
1686                 goto stop_threads;
1687         }
1688
1689         /* Initialize communication library */
1690         lttcomm_init();
1691         /* Initialize TCP timeout values */
1692         lttcomm_inet_init();
1693
1694         /* Create health-check thread. */
1695         if (!launch_health_management_thread()) {
1696                 retval = -1;
1697                 goto stop_threads;
1698         }
1699
1700         /* notification_thread_data acquires the pipes' read side. */
1701         notification_thread_handle = notification_thread_handle_create(
1702                         ust32_channel_monitor_pipe,
1703                         ust64_channel_monitor_pipe,
1704                         kernel_channel_monitor_pipe);
1705         if (!notification_thread_handle) {
1706                 retval = -1;
1707                 ERR("Failed to create notification thread shared data");
1708                 goto stop_threads;
1709         }
1710
1711         /* Create notification thread. */
1712         notification_thread = launch_notification_thread(
1713                         notification_thread_handle);
1714         if (!notification_thread) {
1715                 retval = -1;
1716                 goto stop_threads;
1717         }
1718
1719         /* Create timer thread. */
1720         if (!launch_timer_thread(&timer_thread_parameters)) {
1721                 retval = -1;
1722                 goto stop_threads;
1723         }
1724
1725         /* rotation_thread_data acquires the pipes' read side. */
1726         rotation_thread_handle = rotation_thread_handle_create(
1727                         rotation_timer_queue,
1728                         notification_thread_handle);
1729         if (!rotation_thread_handle) {
1730                 retval = -1;
1731                 ERR("Failed to create rotation thread shared data");
1732                 stop_threads();
1733                 goto stop_threads;
1734         }
1735
1736         /* Create rotation thread. */
1737         if (!launch_rotation_thread(rotation_thread_handle)) {
1738                 retval = -1;
1739                 goto stop_threads;
1740         }
1741
1742         /* Create thread to manage the client socket */
1743         client_thread = launch_client_thread();
1744         if (!client_thread) {
1745                 retval = -1;
1746                 goto stop_threads;
1747         }
1748
1749         /* Set credentials of the client socket and rundir */
1750         if (is_root && set_permissions(config.rundir.value)) {
1751                 retval = -1;
1752                 goto stop_threads;
1753         }
1754
1755         if (!launch_ust_dispatch_thread(&ust_cmd_queue, apps_cmd_pipe[1],
1756                         apps_cmd_notify_pipe[1])) {
1757                 retval = -1;
1758                 goto stop_threads;
1759         }
1760
1761         /* Create thread to manage application registration. */
1762         register_apps_thread = launch_application_registration_thread(
1763                         &ust_cmd_queue);
1764         if (!register_apps_thread) {
1765                 retval = -1;
1766                 goto stop_threads;
1767         }
1768
1769         /* Create thread to manage application socket */
1770         if (!launch_application_management_thread(apps_cmd_pipe[0])) {
1771                 retval = -1;
1772                 goto stop_threads;
1773         }
1774
1775         /* Create thread to manage application notify socket */
1776         if (!launch_application_notification_thread(apps_cmd_notify_pipe[0])) {
1777                 retval = -1;
1778                 goto stop_threads;
1779         }
1780
1781         /* Create agent management thread. */
1782         if (!launch_agent_management_thread()) {
1783                 retval = -1;
1784                 goto stop_threads;
1785         }
1786
1787         /* Don't start this thread if kernel tracing is not requested nor root */
1788         if (is_root && !config.no_kernel) {
1789                 /* Create kernel thread to manage kernel event */
1790                 if (!launch_kernel_management_thread(kernel_poll_pipe[0])) {
1791                         retval = -1;
1792                         goto stop_threads;
1793                 }
1794
1795                 if (kernel_get_notification_fd() >= 0) {
1796                         ret = notification_thread_command_add_tracer_event_source(
1797                                         notification_thread_handle,
1798                                         kernel_get_notification_fd(),
1799                                         LTTNG_DOMAIN_KERNEL);
1800                         if (ret != LTTNG_OK) {
1801                                 ERR("Failed to add kernel trigger event source to notification thread");
1802                                 retval = -1;
1803                                 goto stop_threads;
1804                         }
1805                 }
1806         }
1807
1808         /* Load sessions. */
1809         ret = config_load_session(config.load_session_path.value,
1810                         NULL, 1, 1, NULL);
1811         if (ret) {
1812                 ERR("Session load failed: %s", error_get_str(ret));
1813                 retval = -1;
1814                 goto stop_threads;
1815         }
1816
1817         /* Initialization completed. */
1818         sessiond_signal_parents();
1819
1820         /*
1821          * This is where we start awaiting program completion (e.g. through
1822          * signal that asks threads to teardown).
1823          */
1824
1825         /* Initiate teardown once activity occurs on the quit pipe. */
1826         sessiond_wait_for_quit_pipe(-1);
1827
1828 stop_threads:
1829         /*
1830          * Ensure that the client thread is no longer accepting new commands,
1831          * which could cause new sessions to be created.
1832          */
1833         if (client_thread) {
1834                 lttng_thread_shutdown(client_thread);
1835                 lttng_thread_put(client_thread);
1836         }
1837
1838         destroy_all_sessions_and_wait();
1839
1840         /*
1841          * At this point no new trigger can be registered (no sessions are
1842          * running/rotating) and clients can't connect to the session daemon
1843          * anymore. Unregister all triggers.
1844          */
1845         unregister_all_triggers();
1846
1847         if (register_apps_thread) {
1848                 lttng_thread_shutdown(register_apps_thread);
1849                 lttng_thread_put(register_apps_thread);
1850         }
1851         lttng_thread_list_shutdown_orphans();
1852
1853         /*
1854          * Wait for all pending call_rcu work to complete before tearing
1855          * down data structures. call_rcu worker may be trying to
1856          * perform lookups in those structures.
1857          */
1858         rcu_barrier();
1859         /*
1860          * sessiond_cleanup() is called when no other thread is running, except
1861          * the ht_cleanup thread, which is needed to destroy the hash tables.
1862          */
1863         rcu_thread_online();
1864         sessiond_cleanup();
1865
1866         /*
1867          * Wait for all pending call_rcu work to complete tearing shutting down
1868          * the notification thread. This call_rcu work includes shutting down
1869          * UST apps and event notifier pipes.
1870          */
1871         rcu_barrier();
1872
1873         if (notification_thread) {
1874                 lttng_thread_shutdown(notification_thread);
1875                 lttng_thread_put(notification_thread);
1876         }
1877
1878         /*
1879          * Ensure all prior call_rcu are done. call_rcu callbacks may push
1880          * hash tables to the ht_cleanup thread. Therefore, we ensure that
1881          * the queue is empty before shutting down the clean-up thread.
1882          */
1883         rcu_barrier();
1884
1885         if (ht_cleanup_thread) {
1886                 lttng_thread_shutdown(ht_cleanup_thread);
1887                 lttng_thread_put(ht_cleanup_thread);
1888         }
1889
1890         rcu_thread_offline();
1891         rcu_unregister_thread();
1892
1893         if (rotation_thread_handle) {
1894                 rotation_thread_handle_destroy(rotation_thread_handle);
1895         }
1896
1897         /*
1898          * After the rotation and timer thread have quit, we can safely destroy
1899          * the rotation_timer_queue.
1900          */
1901         rotation_thread_timer_queue_destroy(rotation_timer_queue);
1902         /*
1903          * The teardown of the notification system is performed after the
1904          * session daemon's teardown in order to allow it to be notified
1905          * of the active session and channels at the moment of the teardown.
1906          */
1907         if (notification_thread_handle) {
1908                 notification_thread_handle_destroy(notification_thread_handle);
1909         }
1910         lttng_pipe_destroy(ust32_channel_monitor_pipe);
1911         lttng_pipe_destroy(ust64_channel_monitor_pipe);
1912         lttng_pipe_destroy(kernel_channel_monitor_pipe);
1913
1914         if (health_sessiond) {
1915                 health_app_destroy(health_sessiond);
1916         }
1917 exit_create_run_as_worker_cleanup:
1918 exit_options:
1919         sessiond_cleanup_lock_file();
1920         sessiond_cleanup_options();
1921
1922 exit_set_signal_handler:
1923         if (!retval) {
1924                 exit(EXIT_SUCCESS);
1925         } else {
1926                 exit(EXIT_FAILURE);
1927         }
1928 }