src/bin/lttng-sessiond/main.c

   1 /*
   2  * Copyright (C) 2011 EfficiOS Inc.
   3  * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  * Copyright (C) 2013 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   5  *
   6  * SPDX-License-Identifier: GPL-2.0-only
   7  *
   8  */
   9
  10 #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/path.h>
  41 #include <common/daemonize.h>
  42 #include <common/config/session-config.h>
  43 #include <common/dynamic-buffer.h>
  44 #include <lttng/event-internal.h>
  45
  46 #include "lttng-sessiond.h"
  47 #include "buffer-registry.h"
  48 #include "channel.h"
  49 #include "cmd.h"
  50 #include "consumer.h"
  51 #include "context.h"
  52 #include "event.h"
  53 #include "kernel.h"
  54 #include "kernel-consumer.h"
  55 #include "shm.h"
  56 #include "lttng-ust-ctl.h"
  57 #include "ust-consumer.h"
  58 #include "utils.h"
  59 #include "fd-limit.h"
  60 #include "health-sessiond.h"
  61 #include "testpoint.h"
  62 #include "notify-apps.h"
  63 #include "agent-thread.h"
  64 #include "save.h"
  65 #include "notification-thread.h"
  66 #include "notification-thread-commands.h"
  67 #include "rotation-thread.h"
  68 #include "agent.h"
  69 #include "ht-cleanup.h"
  70 #include "sessiond-config.h"
  71 #include "timer.h"
  72 #include "thread.h"
  73 #include "client.h"
  74 #include "dispatch.h"
  75 #include "register.h"
  76 #include "manage-apps.h"
  77 #include "manage-kernel.h"
  78
  79 static const char *help_msg =
  80 #ifdef LTTNG_EMBED_HELP
  81 #include <lttng-sessiond.8.h>
  82 #else
  83 NULL
  84 #endif
  85 ;
  86
  87 const char *progname;
  88 static int lockfile_fd = -1;
  89 static int opt_print_version;
  90
  91 /* Set to 1 when a SIGUSR1 signal is received. */
  92 static int recv_child_signal;
  93
  94 /* Command line options */
  95 static const struct option long_options[] = {
  96         { "client-sock", required_argument, 0, 'c' },
  97         { "apps-sock", required_argument, 0, 'a' },
  98         { "kconsumerd-cmd-sock", required_argument, 0, '\0' },
  99         { "kconsumerd-err-sock", required_argument, 0, '\0' },
 100         { "ustconsumerd32-cmd-sock", required_argument, 0, '\0' },
 101         { "ustconsumerd32-err-sock", required_argument, 0, '\0' },
 102         { "ustconsumerd64-cmd-sock", required_argument, 0, '\0' },
 103         { "ustconsumerd64-err-sock", required_argument, 0, '\0' },
 104         { "consumerd32-path", required_argument, 0, '\0' },
 105         { "consumerd32-libdir", required_argument, 0, '\0' },
 106         { "consumerd64-path", required_argument, 0, '\0' },
 107         { "consumerd64-libdir", required_argument, 0, '\0' },
 108         { "daemonize", no_argument, 0, 'd' },
 109         { "background", no_argument, 0, 'b' },
 110         { "sig-parent", no_argument, 0, 'S' },
 111         { "help", no_argument, 0, 'h' },
 112         { "group", required_argument, 0, 'g' },
 113         { "version", no_argument, 0, 'V' },
 114         { "quiet", no_argument, 0, 'q' },
 115         { "verbose", no_argument, 0, 'v' },
 116         { "verbose-consumer", no_argument, 0, '\0' },
 117         { "no-kernel", no_argument, 0, '\0' },
 118         { "pidfile", required_argument, 0, 'p' },
 119         { "agent-tcp-port", required_argument, 0, '\0' },
 120         { "config", required_argument, 0, 'f' },
 121         { "load", required_argument, 0, 'l' },
 122         { "kmod-probes", required_argument, 0, '\0' },
 123         { "extra-kmod-probes", required_argument, 0, '\0' },
 124         { NULL, 0, 0, 0 }
 125 };
 126
 127 /* Command line options to ignore from configuration file */
 128 static const char *config_ignore_options[] = { "help", "version", "config" };
 129
 130 /*
 131  * This pipe is used to inform the thread managing application communication
 132  * that a command is queued and ready to be processed.
 133  */
 134 static int apps_cmd_pipe[2] = { -1, -1 };
 135 static int apps_cmd_notify_pipe[2] = { -1, -1 };
 136
 137 /*
 138  * UST registration command queue. This queue is tied with a futex and uses a N
 139  * wakers / 1 waiter implemented and detailed in futex.c/.h
 140  *
 141  * The thread_registration_apps and thread_dispatch_ust_registration uses this
 142  * queue along with the wait/wake scheme. The thread_manage_apps receives down
 143  * the line new application socket and monitors it for any I/O error or clean
 144  * close that triggers an unregistration of the application.
 145  */
 146 static struct ust_cmd_queue ust_cmd_queue;
 147
 148 /*
 149  * Section name to look for in the daemon configuration file.
 150  */
 151 static const char * const config_section_name = "sessiond";
 152
 153 /* Am I root or not. Set to 1 if the daemon is running as root */
 154 static int is_root;
 155
 156 /*
 157  * Stop all threads by closing the thread quit pipe.
 158  */
 159 static void stop_threads(void)
 160 {
 161         int ret;
 162
 163         /* Stopping all threads */
 164         DBG("Terminating all threads");
 165         ret = sessiond_notify_quit_pipe();
 166         if (ret < 0) {
 167                 ERR("write error on thread quit pipe");
 168         }
 169 }
 170
 171 /*
 172  * Close every consumer sockets.
 173  */
 174 static void close_consumer_sockets(void)
 175 {
 176         int ret;
 177
 178         if (kconsumer_data.err_sock >= 0) {
 179                 ret = close(kconsumer_data.err_sock);
 180                 if (ret < 0) {
 181                         PERROR("kernel consumer err_sock close");
 182                 }
 183         }
 184         if (ustconsumer32_data.err_sock >= 0) {
 185                 ret = close(ustconsumer32_data.err_sock);
 186                 if (ret < 0) {
 187                         PERROR("UST consumerd32 err_sock close");
 188                 }
 189         }
 190         if (ustconsumer64_data.err_sock >= 0) {
 191                 ret = close(ustconsumer64_data.err_sock);
 192                 if (ret < 0) {
 193                         PERROR("UST consumerd64 err_sock close");
 194                 }
 195         }
 196         if (kconsumer_data.cmd_sock >= 0) {
 197                 ret = close(kconsumer_data.cmd_sock);
 198                 if (ret < 0) {
 199                         PERROR("kernel consumer cmd_sock close");
 200                 }
 201         }
 202         if (ustconsumer32_data.cmd_sock >= 0) {
 203                 ret = close(ustconsumer32_data.cmd_sock);
 204                 if (ret < 0) {
 205                         PERROR("UST consumerd32 cmd_sock close");
 206                 }
 207         }
 208         if (ustconsumer64_data.cmd_sock >= 0) {
 209                 ret = close(ustconsumer64_data.cmd_sock);
 210                 if (ret < 0) {
 211                         PERROR("UST consumerd64 cmd_sock close");
 212                 }
 213         }
 214         if (kconsumer_data.channel_monitor_pipe >= 0) {
 215                 ret = close(kconsumer_data.channel_monitor_pipe);
 216                 if (ret < 0) {
 217                         PERROR("kernel consumer channel monitor pipe close");
 218                 }
 219         }
 220         if (ustconsumer32_data.channel_monitor_pipe >= 0) {
 221                 ret = close(ustconsumer32_data.channel_monitor_pipe);
 222                 if (ret < 0) {
 223                         PERROR("UST consumerd32 channel monitor pipe close");
 224                 }
 225         }
 226         if (ustconsumer64_data.channel_monitor_pipe >= 0) {
 227                 ret = close(ustconsumer64_data.channel_monitor_pipe);
 228                 if (ret < 0) {
 229                         PERROR("UST consumerd64 channel monitor pipe close");
 230                 }
 231         }
 232 }
 233
 234 /*
 235  * Wait on consumer process termination.
 236  *
 237  * Need to be called with the consumer data lock held or from a context
 238  * ensuring no concurrent access to data (e.g: cleanup).
 239  */
 240 static void wait_consumer(struct consumer_data *consumer_data)
 241 {
 242         pid_t ret;
 243         int status;
 244
 245         if (consumer_data->pid <= 0) {
 246                 return;
 247         }
 248
 249         DBG("Waiting for complete teardown of consumerd (PID: %d)",
 250                         consumer_data->pid);
 251         ret = waitpid(consumer_data->pid, &status, 0);
 252         if (ret == -1) {
 253                 PERROR("consumerd waitpid pid: %d", consumer_data->pid)
 254         } else  if (!WIFEXITED(status)) {
 255                 ERR("consumerd termination with error: %d",
 256                                 WEXITSTATUS(ret));
 257         }
 258         consumer_data->pid = 0;
 259 }
 260
 261 /*
 262  * Cleanup the session daemon's data structures.
 263  */
 264 static void sessiond_cleanup(void)
 265 {
 266         int ret;
 267         struct ltt_session_list *session_list = session_get_list();
 268
 269         DBG("Cleanup sessiond");
 270
 271         /*
 272          * Close the thread quit pipe. It has already done its job,
 273          * since we are now called.
 274          */
 275         sessiond_close_quit_pipe();
 276         utils_close_pipe(apps_cmd_pipe);
 277         utils_close_pipe(apps_cmd_notify_pipe);
 278         utils_close_pipe(kernel_poll_pipe);
 279
 280         ret = remove(config.pid_file_path.value);
 281         if (ret < 0) {
 282                 PERROR("remove pidfile %s", config.pid_file_path.value);
 283         }
 284
 285         DBG("Removing sessiond and consumerd content of directory %s",
 286                 config.rundir.value);
 287
 288         /* sessiond */
 289         DBG("Removing %s", config.pid_file_path.value);
 290         (void) unlink(config.pid_file_path.value);
 291
 292         DBG("Removing %s", config.agent_port_file_path.value);
 293         (void) unlink(config.agent_port_file_path.value);
 294
 295         /* kconsumerd */
 296         DBG("Removing %s", kconsumer_data.err_unix_sock_path);
 297         (void) unlink(kconsumer_data.err_unix_sock_path);
 298
 299         DBG("Removing directory %s", config.kconsumerd_path.value);
 300         (void) rmdir(config.kconsumerd_path.value);
 301
 302         /* ust consumerd 32 */
 303         DBG("Removing %s", config.consumerd32_err_unix_sock_path.value);
 304         (void) unlink(config.consumerd32_err_unix_sock_path.value);
 305
 306         DBG("Removing directory %s", config.consumerd32_path.value);
 307         (void) rmdir(config.consumerd32_path.value);
 308
 309         /* ust consumerd 64 */
 310         DBG("Removing %s", config.consumerd64_err_unix_sock_path.value);
 311         (void) unlink(config.consumerd64_err_unix_sock_path.value);
 312
 313         DBG("Removing directory %s", config.consumerd64_path.value);
 314         (void) rmdir(config.consumerd64_path.value);
 315
 316         pthread_mutex_destroy(&session_list->lock);
 317
 318         DBG("Cleaning up all agent apps");
 319         agent_app_ht_clean();
 320         DBG("Closing all UST sockets");
 321         ust_app_clean_list();
 322         buffer_reg_destroy_registries();
 323
 324         close_consumer_sockets();
 325
 326         wait_consumer(&kconsumer_data);
 327         wait_consumer(&ustconsumer64_data);
 328         wait_consumer(&ustconsumer32_data);
 329
 330         if (is_root && !config.no_kernel) {
 331                 cleanup_kernel_tracer();
 332         }
 333
 334         /*
 335          * We do NOT rmdir rundir because there are other processes
 336          * using it, for instance lttng-relayd, which can start in
 337          * parallel with this teardown.
 338          */
 339 }
 340
 341 /*
 342  * Cleanup the daemon's option data structures.
 343  */
 344 static void sessiond_cleanup_options(void)
 345 {
 346         DBG("Cleaning up options");
 347
 348         sessiond_config_fini(&config);
 349
 350         run_as_destroy_worker();
 351 }
 352
 353 static int string_match(const char *str1, const char *str2)
 354 {
 355         return (str1 && str2) && !strcmp(str1, str2);
 356 }
 357
 358 /*
 359  * Take an option from the getopt output and set it in the right variable to be
 360  * used later.
 361  *
 362  * Return 0 on success else a negative value.
 363  */
 364 static int set_option(int opt, const char *arg, const char *optname)
 365 {
 366         int ret = 0;
 367
 368         if (string_match(optname, "client-sock") || opt == 'c') {
 369                 if (!arg || *arg == '\0') {
 370                         ret = -EINVAL;
 371                         goto end;
 372                 }
 373                 if (lttng_is_setuid_setgid()) {
 374                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 375                                 "-c, --client-sock");
 376                 } else {
 377                         config_string_set(&config.client_unix_sock_path,
 378                                         strdup(arg));
 379                         if (!config.client_unix_sock_path.value) {
 380                                 ret = -ENOMEM;
 381                                 PERROR("strdup");
 382                         }
 383                 }
 384         } else if (string_match(optname, "apps-sock") || opt == 'a') {
 385                 if (!arg || *arg == '\0') {
 386                         ret = -EINVAL;
 387                         goto end;
 388                 }
 389                 if (lttng_is_setuid_setgid()) {
 390                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 391                                 "-a, --apps-sock");
 392                 } else {
 393                         config_string_set(&config.apps_unix_sock_path,
 394                                         strdup(arg));
 395                         if (!config.apps_unix_sock_path.value) {
 396                                 ret = -ENOMEM;
 397                                 PERROR("strdup");
 398                         }
 399                 }
 400         } else if (string_match(optname, "daemonize") || opt == 'd') {
 401                 config.daemonize = true;
 402         } else if (string_match(optname, "background") || opt == 'b') {
 403                 config.background = true;
 404         } else if (string_match(optname, "group") || opt == 'g') {
 405                 if (!arg || *arg == '\0') {
 406                         ret = -EINVAL;
 407                         goto end;
 408                 }
 409                 if (lttng_is_setuid_setgid()) {
 410                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 411                                 "-g, --group");
 412                 } else {
 413                         config_string_set(&config.tracing_group_name,
 414                                         strdup(arg));
 415                         if (!config.tracing_group_name.value) {
 416                                 ret = -ENOMEM;
 417                                 PERROR("strdup");
 418                         }
 419                 }
 420         } else if (string_match(optname, "help") || opt == 'h') {
 421                 ret = utils_show_help(8, "lttng-sessiond", help_msg);
 422                 if (ret) {
 423                         ERR("Cannot show --help for `lttng-sessiond`");
 424                         perror("exec");
 425                 }
 426                 exit(ret ? EXIT_FAILURE : EXIT_SUCCESS);
 427         } else if (string_match(optname, "version") || opt == 'V') {
 428                 opt_print_version = 1;
 429         } else if (string_match(optname, "sig-parent") || opt == 'S') {
 430                 config.sig_parent = true;
 431         } else if (string_match(optname, "kconsumerd-err-sock")) {
 432                 if (!arg || *arg == '\0') {
 433                         ret = -EINVAL;
 434                         goto end;
 435                 }
 436                 if (lttng_is_setuid_setgid()) {
 437                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 438                                 "--kconsumerd-err-sock");
 439                 } else {
 440                         config_string_set(&config.kconsumerd_err_unix_sock_path,
 441                                         strdup(arg));
 442                         if (!config.kconsumerd_err_unix_sock_path.value) {
 443                                 ret = -ENOMEM;
 444                                 PERROR("strdup");
 445                         }
 446                 }
 447         } else if (string_match(optname, "kconsumerd-cmd-sock")) {
 448                 if (!arg || *arg == '\0') {
 449                         ret = -EINVAL;
 450                         goto end;
 451                 }
 452                 if (lttng_is_setuid_setgid()) {
 453                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 454                                 "--kconsumerd-cmd-sock");
 455                 } else {
 456                         config_string_set(&config.kconsumerd_cmd_unix_sock_path,
 457                                         strdup(arg));
 458                         if (!config.kconsumerd_cmd_unix_sock_path.value) {
 459                                 ret = -ENOMEM;
 460                                 PERROR("strdup");
 461                         }
 462                 }
 463         } else if (string_match(optname, "ustconsumerd64-err-sock")) {
 464                 if (!arg || *arg == '\0') {
 465                         ret = -EINVAL;
 466                         goto end;
 467                 }
 468                 if (lttng_is_setuid_setgid()) {
 469                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 470                                 "--ustconsumerd64-err-sock");
 471                 } else {
 472                         config_string_set(&config.consumerd64_err_unix_sock_path,
 473                                         strdup(arg));
 474                         if (!config.consumerd64_err_unix_sock_path.value) {
 475                                 ret = -ENOMEM;
 476                                 PERROR("strdup");
 477                         }
 478                 }
 479         } else if (string_match(optname, "ustconsumerd64-cmd-sock")) {
 480                 if (!arg || *arg == '\0') {
 481                         ret = -EINVAL;
 482                         goto end;
 483                 }
 484                 if (lttng_is_setuid_setgid()) {
 485                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 486                                 "--ustconsumerd64-cmd-sock");
 487                 } else {
 488                         config_string_set(&config.consumerd64_cmd_unix_sock_path,
 489                                         strdup(arg));
 490                         if (!config.consumerd64_cmd_unix_sock_path.value) {
 491                                 ret = -ENOMEM;
 492                                 PERROR("strdup");
 493                         }
 494                 }
 495         } else if (string_match(optname, "ustconsumerd32-err-sock")) {
 496                 if (!arg || *arg == '\0') {
 497                         ret = -EINVAL;
 498                         goto end;
 499                 }
 500                 if (lttng_is_setuid_setgid()) {
 501                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 502                                 "--ustconsumerd32-err-sock");
 503                 } else {
 504                         config_string_set(&config.consumerd32_err_unix_sock_path,
 505                                         strdup(arg));
 506                         if (!config.consumerd32_err_unix_sock_path.value) {
 507                                 ret = -ENOMEM;
 508                                 PERROR("strdup");
 509                         }
 510                 }
 511         } else if (string_match(optname, "ustconsumerd32-cmd-sock")) {
 512                 if (!arg || *arg == '\0') {
 513                         ret = -EINVAL;
 514                         goto end;
 515                 }
 516                 if (lttng_is_setuid_setgid()) {
 517                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 518                                 "--ustconsumerd32-cmd-sock");
 519                 } else {
 520                         config_string_set(&config.consumerd32_cmd_unix_sock_path,
 521                                         strdup(arg));
 522                         if (!config.consumerd32_cmd_unix_sock_path.value) {
 523                                 ret = -ENOMEM;
 524                                 PERROR("strdup");
 525                         }
 526                 }
 527         } else if (string_match(optname, "no-kernel")) {
 528                 config.no_kernel = true;
 529         } else if (string_match(optname, "quiet") || opt == 'q') {
 530                 config.quiet = true;
 531         } else if (string_match(optname, "verbose") || opt == 'v') {
 532                 /* Verbose level can increase using multiple -v */
 533                 if (arg) {
 534                         /* Value obtained from config file */
 535                         config.verbose = config_parse_value(arg);
 536                 } else {
 537                         /* -v used on command line */
 538                         config.verbose++;
 539                 }
 540                 /* Clamp value to [0, 3] */
 541                 config.verbose = config.verbose < 0 ? 0 :
 542                         (config.verbose <= 3 ? config.verbose : 3);
 543         } else if (string_match(optname, "verbose-consumer")) {
 544                 if (arg) {
 545                         config.verbose_consumer = config_parse_value(arg);
 546                 } else {
 547                         config.verbose_consumer++;
 548                 }
 549         } else if (string_match(optname, "consumerd32-path")) {
 550                 if (!arg || *arg == '\0') {
 551                         ret = -EINVAL;
 552                         goto end;
 553                 }
 554                 if (lttng_is_setuid_setgid()) {
 555                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 556                                 "--consumerd32-path");
 557                 } else {
 558                         config_string_set(&config.consumerd32_bin_path,
 559                                         strdup(arg));
 560                         if (!config.consumerd32_bin_path.value) {
 561                                 PERROR("strdup");
 562                                 ret = -ENOMEM;
 563                         }
 564                 }
 565         } else if (string_match(optname, "consumerd32-libdir")) {
 566                 if (!arg || *arg == '\0') {
 567                         ret = -EINVAL;
 568                         goto end;
 569                 }
 570                 if (lttng_is_setuid_setgid()) {
 571                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 572                                 "--consumerd32-libdir");
 573                 } else {
 574                         config_string_set(&config.consumerd32_lib_dir,
 575                                         strdup(arg));
 576                         if (!config.consumerd32_lib_dir.value) {
 577                                 PERROR("strdup");
 578                                 ret = -ENOMEM;
 579                         }
 580                 }
 581         } else if (string_match(optname, "consumerd64-path")) {
 582                 if (!arg || *arg == '\0') {
 583                         ret = -EINVAL;
 584                         goto end;
 585                 }
 586                 if (lttng_is_setuid_setgid()) {
 587                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 588                                 "--consumerd64-path");
 589                 } else {
 590                         config_string_set(&config.consumerd64_bin_path,
 591                                         strdup(arg));
 592                         if (!config.consumerd64_bin_path.value) {
 593                                 PERROR("strdup");
 594                                 ret = -ENOMEM;
 595                         }
 596                 }
 597         } else if (string_match(optname, "consumerd64-libdir")) {
 598                 if (!arg || *arg == '\0') {
 599                         ret = -EINVAL;
 600                         goto end;
 601                 }
 602                 if (lttng_is_setuid_setgid()) {
 603                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 604                                 "--consumerd64-libdir");
 605                 } else {
 606                         config_string_set(&config.consumerd64_lib_dir,
 607                                         strdup(arg));
 608                         if (!config.consumerd64_lib_dir.value) {
 609                                 PERROR("strdup");
 610                                 ret = -ENOMEM;
 611                         }
 612                 }
 613         } else if (string_match(optname, "pidfile") || opt == 'p') {
 614                 if (!arg || *arg == '\0') {
 615                         ret = -EINVAL;
 616                         goto end;
 617                 }
 618                 if (lttng_is_setuid_setgid()) {
 619                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 620                                 "-p, --pidfile");
 621                 } else {
 622                         config_string_set(&config.pid_file_path, strdup(arg));
 623                         if (!config.pid_file_path.value) {
 624                                 PERROR("strdup");
 625                                 ret = -ENOMEM;
 626                         }
 627                 }
 628         } else if (string_match(optname, "agent-tcp-port")) {
 629                 if (!arg || *arg == '\0') {
 630                         ret = -EINVAL;
 631                         goto end;
 632                 }
 633                 if (lttng_is_setuid_setgid()) {
 634                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 635                                 "--agent-tcp-port");
 636                 } else {
 637                         unsigned long v;
 638
 639                         errno = 0;
 640                         v = strtoul(arg, NULL, 0);
 641                         if (errno != 0 || !isdigit(arg[0])) {
 642                                 ERR("Wrong value in --agent-tcp-port parameter: %s", arg);
 643                                 return -1;
 644                         }
 645                         if (v == 0 || v >= 65535) {
 646                                 ERR("Port overflow in --agent-tcp-port parameter: %s", arg);
 647                                 return -1;
 648                         }
 649                         config.agent_tcp_port.begin = config.agent_tcp_port.end = (int) v;
 650                         DBG3("Agent TCP port set to non default: %i", (int) v);
 651                 }
 652         } else if (string_match(optname, "load") || opt == 'l') {
 653                 if (!arg || *arg == '\0') {
 654                         ret = -EINVAL;
 655                         goto end;
 656                 }
 657                 if (lttng_is_setuid_setgid()) {
 658                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 659                                 "-l, --load");
 660                 } else {
 661                         config_string_set(&config.load_session_path, strdup(arg));
 662                         if (!config.load_session_path.value) {
 663                                 PERROR("strdup");
 664                                 ret = -ENOMEM;
 665                         }
 666                 }
 667         } else if (string_match(optname, "kmod-probes")) {
 668                 if (!arg || *arg == '\0') {
 669                         ret = -EINVAL;
 670                         goto end;
 671                 }
 672                 if (lttng_is_setuid_setgid()) {
 673                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 674                                 "--kmod-probes");
 675                 } else {
 676                         config_string_set(&config.kmod_probes_list, strdup(arg));
 677                         if (!config.kmod_probes_list.value) {
 678                                 PERROR("strdup");
 679                                 ret = -ENOMEM;
 680                         }
 681                 }
 682         } else if (string_match(optname, "extra-kmod-probes")) {
 683                 if (!arg || *arg == '\0') {
 684                         ret = -EINVAL;
 685                         goto end;
 686                 }
 687                 if (lttng_is_setuid_setgid()) {
 688                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 689                                 "--extra-kmod-probes");
 690                 } else {
 691                         config_string_set(&config.kmod_extra_probes_list,
 692                                         strdup(arg));
 693                         if (!config.kmod_extra_probes_list.value) {
 694                                 PERROR("strdup");
 695                                 ret = -ENOMEM;
 696                         }
 697                 }
 698         } else if (string_match(optname, "config") || opt == 'f') {
 699                 /* This is handled in set_options() thus silent skip. */
 700                 goto end;
 701         } else {
 702                 /* Unknown option or other error.
 703                  * Error is printed by getopt, just return */
 704                 ret = -1;
 705         }
 706
 707 end:
 708         if (ret == -EINVAL) {
 709                 const char *opt_name = "unknown";
 710                 int i;
 711
 712                 for (i = 0; i < sizeof(long_options) / sizeof(struct option);
 713                         i++) {
 714                         if (opt == long_options[i].val) {
 715                                 opt_name = long_options[i].name;
 716                                 break;
 717                         }
 718                 }
 719
 720                 WARN("Invalid argument provided for option \"%s\", using default value.",
 721                         opt_name);
 722         }
 723
 724         return ret;
 725 }
 726
 727 /*
 728  * config_entry_handler_cb used to handle options read from a config file.
 729  * See config_entry_handler_cb comment in common/config/session-config.h for the
 730  * return value conventions.
 731  */
 732 static int config_entry_handler(const struct config_entry *entry, void *unused)
 733 {
 734         int ret = 0, i;
 735
 736         if (!entry || !entry->name || !entry->value) {
 737                 ret = -EINVAL;
 738                 goto end;
 739         }
 740
 741         /* Check if the option is to be ignored */
 742         for (i = 0; i < sizeof(config_ignore_options) / sizeof(char *); i++) {
 743                 if (!strcmp(entry->name, config_ignore_options[i])) {
 744                         goto end;
 745                 }
 746         }
 747
 748         for (i = 0; i < (sizeof(long_options) / sizeof(struct option)) - 1;
 749                 i++) {
 750
 751                 /* Ignore if not fully matched. */
 752                 if (strcmp(entry->name, long_options[i].name)) {
 753                         continue;
 754                 }
 755
 756                 /*
 757                  * If the option takes no argument on the command line, we have to
 758                  * check if the value is "true". We support non-zero numeric values,
 759                  * true, on and yes.
 760                  */
 761                 if (!long_options[i].has_arg) {
 762                         ret = config_parse_value(entry->value);
 763                         if (ret <= 0) {
 764                                 if (ret) {
 765                                         WARN("Invalid configuration value \"%s\" for option %s",
 766                                                         entry->value, entry->name);
 767                                 }
 768                                 /* False, skip boolean config option. */
 769                                 goto end;
 770                         }
 771                 }
 772
 773                 ret = set_option(long_options[i].val, entry->value, entry->name);
 774                 goto end;
 775         }
 776
 777         WARN("Unrecognized option \"%s\" in daemon configuration file.", entry->name);
 778
 779 end:
 780         return ret;
 781 }
 782
 783 static void print_version(void) {
 784         fprintf(stdout, "%s\n", VERSION);
 785 }
 786
 787 /*
 788  * daemon configuration loading and argument parsing
 789  */
 790 static int set_options(int argc, char **argv)
 791 {
 792         int ret = 0, c = 0, option_index = 0;
 793         int orig_optopt = optopt, orig_optind = optind;
 794         char *optstring;
 795         char *config_path = NULL;
 796
 797         optstring = utils_generate_optstring(long_options,
 798                         sizeof(long_options) / sizeof(struct option));
 799         if (!optstring) {
 800                 ret = -ENOMEM;
 801                 goto end;
 802         }
 803
 804         /* Check for the --config option */
 805         while ((c = getopt_long(argc, argv, optstring, long_options,
 806                                         &option_index)) != -1) {
 807                 if (c == '?') {
 808                         ret = -EINVAL;
 809                         goto end;
 810                 } else if (c != 'f') {
 811                         /* if not equal to --config option. */
 812                         continue;
 813                 }
 814
 815                 if (lttng_is_setuid_setgid()) {
 816                         WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 817                                 "-f, --config");
 818                 } else {
 819                         free(config_path);
 820                         config_path = utils_expand_path(optarg);
 821                         if (!config_path) {
 822                                 ERR("Failed to resolve path: %s", optarg);
 823                         }
 824                 }
 825         }
 826
 827         ret = config_get_section_entries(config_path, config_section_name,
 828                         config_entry_handler, NULL);
 829         if (ret) {
 830                 if (ret > 0) {
 831                         ERR("Invalid configuration option at line %i", ret);
 832                         ret = -1;
 833                 }
 834                 goto end;
 835         }
 836
 837         /* Reset getopt's global state */
 838         optopt = orig_optopt;
 839         optind = orig_optind;
 840         while (1) {
 841                 option_index = -1;
 842                 /*
 843                  * getopt_long() will not set option_index if it encounters a
 844                  * short option.
 845                  */
 846                 c = getopt_long(argc, argv, optstring, long_options,
 847                                 &option_index);
 848                 if (c == -1) {
 849                         break;
 850                 }
 851
 852                 /*
 853                  * Pass NULL as the long option name if popt left the index
 854                  * unset.
 855                  */
 856                 ret = set_option(c, optarg,
 857                                 option_index < 0 ? NULL :
 858                                 long_options[option_index].name);
 859                 if (ret < 0) {
 860                         break;
 861                 }
 862         }
 863
 864 end:
 865         free(config_path);
 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 int run_as_worker_post_fork_cleanup(void *data)
1261 {
1262         struct sessiond_config *sessiond_config = data;
1263
1264         sessiond_config_fini(sessiond_config);
1265         return 0;
1266 }
1267
1268 static int launch_run_as_worker(const char *procname)
1269 {
1270         /*
1271          * Clean-up before forking the run-as worker. Any dynamically
1272          * allocated memory of which the worker is not aware will
1273          * be leaked as the process forks a run-as worker (and performs
1274          * no exec*()). The same would apply to any opened fd.
1275          */
1276         return run_as_create_worker(procname, run_as_worker_post_fork_cleanup,
1277                         &config);
1278 }
1279
1280 static void sessiond_uuid_log(void)
1281 {
1282         char uuid_str[LTTNG_UUID_STR_LEN];
1283
1284         lttng_uuid_to_str(sessiond_uuid, uuid_str);
1285         DBG("Starting lttng-sessiond {%s}", uuid_str);
1286 }
1287
1288 /*
1289  * main
1290  */
1291 int main(int argc, char **argv)
1292 {
1293         int ret = 0, retval = 0;
1294         const char *env_app_timeout;
1295         struct lttng_pipe *ust32_channel_monitor_pipe = NULL,
1296                         *ust64_channel_monitor_pipe = NULL,
1297                         *kernel_channel_monitor_pipe = NULL;
1298         struct lttng_thread *ht_cleanup_thread = NULL;
1299         struct timer_thread_parameters timer_thread_parameters;
1300         /* Rotation thread handle. */
1301         struct rotation_thread_handle *rotation_thread_handle = NULL;
1302         /* Queue of rotation jobs populated by the sessiond-timer. */
1303         struct rotation_thread_timer_queue *rotation_timer_queue = NULL;
1304         struct lttng_thread *client_thread = NULL;
1305         struct lttng_thread *notification_thread = NULL;
1306         struct lttng_thread *register_apps_thread = NULL;
1307
1308         init_kernel_workarounds();
1309
1310         rcu_register_thread();
1311
1312         if (set_signal_handler()) {
1313                 retval = -1;
1314                 goto exit_set_signal_handler;
1315         }
1316
1317         if (timer_signal_init()) {
1318                 retval = -1;
1319                 goto exit_set_signal_handler;
1320         }
1321
1322         page_size = sysconf(_SC_PAGESIZE);
1323         if (page_size < 0) {
1324                 PERROR("sysconf _SC_PAGESIZE");
1325                 page_size = LONG_MAX;
1326                 WARN("Fallback page size to %ld", page_size);
1327         }
1328
1329         ret = sessiond_config_init(&config);
1330         if (ret) {
1331                 retval = -1;
1332                 goto exit_set_signal_handler;
1333         }
1334
1335         /*
1336          * Init config from environment variables.
1337          * Command line option override env configuration per-doc. Do env first.
1338          */
1339         sessiond_config_apply_env_config(&config);
1340
1341         /*
1342          * Parse arguments and load the daemon configuration file.
1343          *
1344          * We have an exit_options exit path to free memory reserved by
1345          * set_options. This is needed because the rest of sessiond_cleanup()
1346          * depends on ht_cleanup_thread, which depends on lttng_daemonize, which
1347          * depends on set_options.
1348          */
1349         progname = argv[0];
1350         if (set_options(argc, argv)) {
1351                 retval = -1;
1352                 goto exit_options;
1353         }
1354
1355         /*
1356          * Resolve all paths received as arguments, configuration option, or
1357          * through environment variable as absolute paths. This is necessary
1358          * since daemonizing causes the sessiond's current working directory
1359          * to '/'.
1360          */
1361         ret = sessiond_config_resolve_paths(&config);
1362         if (ret) {
1363                 goto exit_options;
1364         }
1365
1366         /* Apply config. */
1367         lttng_opt_verbose = config.verbose;
1368         lttng_opt_quiet = config.quiet;
1369         kconsumer_data.err_unix_sock_path =
1370                         config.kconsumerd_err_unix_sock_path.value;
1371         kconsumer_data.cmd_unix_sock_path =
1372                         config.kconsumerd_cmd_unix_sock_path.value;
1373         ustconsumer32_data.err_unix_sock_path =
1374                         config.consumerd32_err_unix_sock_path.value;
1375         ustconsumer32_data.cmd_unix_sock_path =
1376                         config.consumerd32_cmd_unix_sock_path.value;
1377         ustconsumer64_data.err_unix_sock_path =
1378                         config.consumerd64_err_unix_sock_path.value;
1379         ustconsumer64_data.cmd_unix_sock_path =
1380                         config.consumerd64_cmd_unix_sock_path.value;
1381         set_clock_plugin_env();
1382
1383         sessiond_config_log(&config);
1384         sessiond_uuid_log();
1385
1386         if (opt_print_version) {
1387                 print_version();
1388                 retval = 0;
1389                 goto exit_options;
1390         }
1391
1392         if (create_lttng_rundir()) {
1393                 retval = -1;
1394                 goto exit_options;
1395         }
1396
1397         /* Abort launch if a session daemon is already running. */
1398         if (check_existing_daemon()) {
1399                 ERR("A session daemon is already running.");
1400                 retval = -1;
1401                 goto exit_options;
1402         }
1403
1404         /* Daemonize */
1405         if (config.daemonize || config.background) {
1406                 int i;
1407
1408                 ret = lttng_daemonize(&child_ppid, &recv_child_signal,
1409                         !config.background);
1410                 if (ret < 0) {
1411                         retval = -1;
1412                         goto exit_options;
1413                 }
1414
1415                 /*
1416                  * We are in the child. Make sure all other file descriptors are
1417                  * closed, in case we are called with more opened file
1418                  * descriptors than the standard ones and the lock file.
1419                  */
1420                 for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
1421                         if (i == lockfile_fd) {
1422                                 continue;
1423                         }
1424                         (void) close(i);
1425                 }
1426         }
1427
1428         if (launch_run_as_worker(argv[0]) < 0) {
1429                 goto exit_create_run_as_worker_cleanup;
1430         }
1431
1432         /*
1433          * Starting from here, we can create threads. This needs to be after
1434          * lttng_daemonize due to RCU.
1435          */
1436
1437         /*
1438          * Initialize the health check subsystem. This call should set the
1439          * appropriate time values.
1440          */
1441         health_sessiond = health_app_create(NR_HEALTH_SESSIOND_TYPES);
1442         if (!health_sessiond) {
1443                 PERROR("health_app_create error");
1444                 retval = -1;
1445                 goto stop_threads;
1446         }
1447
1448         /* Create thread to clean up RCU hash tables */
1449         ht_cleanup_thread = launch_ht_cleanup_thread();
1450         if (!ht_cleanup_thread) {
1451                 retval = -1;
1452                 goto stop_threads;
1453         }
1454
1455         /* Create thread quit pipe */
1456         if (sessiond_init_thread_quit_pipe()) {
1457                 retval = -1;
1458                 goto stop_threads;
1459         }
1460
1461         /* Check if daemon is UID = 0 */
1462         is_root = !getuid();
1463         if (is_root) {
1464                 /* Create global run dir with root access */
1465
1466                 kernel_channel_monitor_pipe = lttng_pipe_open(0);
1467                 if (!kernel_channel_monitor_pipe) {
1468                         ERR("Failed to create kernel consumer channel monitor pipe");
1469                         retval = -1;
1470                         goto stop_threads;
1471                 }
1472                 kconsumer_data.channel_monitor_pipe =
1473                                 lttng_pipe_release_writefd(
1474                                         kernel_channel_monitor_pipe);
1475                 if (kconsumer_data.channel_monitor_pipe < 0) {
1476                         retval = -1;
1477                         goto stop_threads;
1478                 }
1479         }
1480
1481         /* Set consumer initial state */
1482         kernel_consumerd_state = CONSUMER_STOPPED;
1483         ust_consumerd_state = CONSUMER_STOPPED;
1484
1485         ust32_channel_monitor_pipe = lttng_pipe_open(0);
1486         if (!ust32_channel_monitor_pipe) {
1487                 ERR("Failed to create 32-bit user space consumer channel monitor pipe");
1488                 retval = -1;
1489                 goto stop_threads;
1490         }
1491         ustconsumer32_data.channel_monitor_pipe = lttng_pipe_release_writefd(
1492                         ust32_channel_monitor_pipe);
1493         if (ustconsumer32_data.channel_monitor_pipe < 0) {
1494                 retval = -1;
1495                 goto stop_threads;
1496         }
1497
1498         /*
1499          * The rotation_thread_timer_queue structure is shared between the
1500          * sessiond timer thread and the rotation thread. The main thread keeps
1501          * its ownership and destroys it when both threads have been joined.
1502          */
1503         rotation_timer_queue = rotation_thread_timer_queue_create();
1504         if (!rotation_timer_queue) {
1505                 retval = -1;
1506                 goto stop_threads;
1507         }
1508         timer_thread_parameters.rotation_thread_job_queue =
1509                         rotation_timer_queue;
1510
1511         ust64_channel_monitor_pipe = lttng_pipe_open(0);
1512         if (!ust64_channel_monitor_pipe) {
1513                 ERR("Failed to create 64-bit user space consumer channel monitor pipe");
1514                 retval = -1;
1515                 goto stop_threads;
1516         }
1517         ustconsumer64_data.channel_monitor_pipe = lttng_pipe_release_writefd(
1518                         ust64_channel_monitor_pipe);
1519         if (ustconsumer64_data.channel_monitor_pipe < 0) {
1520                 retval = -1;
1521                 goto stop_threads;
1522         }
1523
1524         /*
1525          * Init UST app hash table. Alloc hash table before this point since
1526          * cleanup() can get called after that point.
1527          */
1528         if (ust_app_ht_alloc()) {
1529                 ERR("Failed to allocate UST app hash table");
1530                 retval = -1;
1531                 goto stop_threads;
1532         }
1533
1534         /*
1535          * Initialize agent app hash table. We allocate the hash table here
1536          * since cleanup() can get called after this point.
1537          */
1538         if (agent_app_ht_alloc()) {
1539                 ERR("Failed to allocate Agent app hash table");
1540                 retval = -1;
1541                 goto stop_threads;
1542         }
1543
1544         /*
1545          * These actions must be executed as root. We do that *after* setting up
1546          * the sockets path because we MUST make the check for another daemon using
1547          * those paths *before* trying to set the kernel consumer sockets and init
1548          * kernel tracer.
1549          */
1550         if (is_root) {
1551                 if (set_consumer_sockets(&kconsumer_data)) {
1552                         retval = -1;
1553                         goto stop_threads;
1554                 }
1555
1556                 /* Setup kernel tracer */
1557                 if (!config.no_kernel) {
1558                         init_kernel_tracer();
1559                 }
1560
1561                 /* Set ulimit for open files */
1562                 set_ulimit();
1563         }
1564         /* init lttng_fd tracking must be done after set_ulimit. */
1565         lttng_fd_init();
1566
1567         if (set_consumer_sockets(&ustconsumer64_data)) {
1568                 retval = -1;
1569                 goto stop_threads;
1570         }
1571
1572         if (set_consumer_sockets(&ustconsumer32_data)) {
1573                 retval = -1;
1574                 goto stop_threads;
1575         }
1576
1577         /* Get parent pid if -S, --sig-parent is specified. */
1578         if (config.sig_parent) {
1579                 ppid = getppid();
1580         }
1581
1582         /* Setup the kernel pipe for waking up the kernel thread */
1583         if (is_root && !config.no_kernel) {
1584                 if (utils_create_pipe_cloexec(kernel_poll_pipe)) {
1585                         retval = -1;
1586                         goto stop_threads;
1587                 }
1588         }
1589
1590         /* Setup the thread apps communication pipe. */
1591         if (utils_create_pipe_cloexec(apps_cmd_pipe)) {
1592                 retval = -1;
1593                 goto stop_threads;
1594         }
1595
1596         /* Setup the thread apps notify communication pipe. */
1597         if (utils_create_pipe_cloexec(apps_cmd_notify_pipe)) {
1598                 retval = -1;
1599                 goto stop_threads;
1600         }
1601
1602         /* Initialize global buffer per UID and PID registry. */
1603         buffer_reg_init_uid_registry();
1604         buffer_reg_init_pid_registry();
1605
1606         /* Init UST command queue. */
1607         cds_wfcq_init(&ust_cmd_queue.head, &ust_cmd_queue.tail);
1608
1609         cmd_init();
1610
1611         /* Check for the application socket timeout env variable. */
1612         env_app_timeout = getenv(DEFAULT_APP_SOCKET_TIMEOUT_ENV);
1613         if (env_app_timeout) {
1614                 config.app_socket_timeout = atoi(env_app_timeout);
1615         } else {
1616                 config.app_socket_timeout = DEFAULT_APP_SOCKET_RW_TIMEOUT;
1617         }
1618
1619         ret = write_pidfile();
1620         if (ret) {
1621                 ERR("Error in write_pidfile");
1622                 retval = -1;
1623                 goto stop_threads;
1624         }
1625
1626         /* Initialize communication library */
1627         lttcomm_init();
1628         /* Initialize TCP timeout values */
1629         lttcomm_inet_init();
1630
1631         /* Create health-check thread. */
1632         if (!launch_health_management_thread()) {
1633                 retval = -1;
1634                 goto stop_threads;
1635         }
1636
1637         /* notification_thread_data acquires the pipes' read side. */
1638         notification_thread_handle = notification_thread_handle_create(
1639                         ust32_channel_monitor_pipe,
1640                         ust64_channel_monitor_pipe,
1641                         kernel_channel_monitor_pipe);
1642         if (!notification_thread_handle) {
1643                 retval = -1;
1644                 ERR("Failed to create notification thread shared data");
1645                 goto stop_threads;
1646         }
1647
1648         /* Create notification thread. */
1649         notification_thread = launch_notification_thread(
1650                         notification_thread_handle);
1651         if (!notification_thread) {
1652                 retval = -1;
1653                 goto stop_threads;
1654         }
1655
1656         /* Create timer thread. */
1657         if (!launch_timer_thread(&timer_thread_parameters)) {
1658                 retval = -1;
1659                 goto stop_threads;
1660         }
1661
1662         /* rotation_thread_data acquires the pipes' read side. */
1663         rotation_thread_handle = rotation_thread_handle_create(
1664                         rotation_timer_queue,
1665                         notification_thread_handle);
1666         if (!rotation_thread_handle) {
1667                 retval = -1;
1668                 ERR("Failed to create rotation thread shared data");
1669                 stop_threads();
1670                 goto stop_threads;
1671         }
1672
1673         /* Create rotation thread. */
1674         if (!launch_rotation_thread(rotation_thread_handle)) {
1675                 retval = -1;
1676                 goto stop_threads;
1677         }
1678
1679         /* Create thread to manage the client socket */
1680         client_thread = launch_client_thread();
1681         if (!client_thread) {
1682                 retval = -1;
1683                 goto stop_threads;
1684         }
1685
1686         /* Set credentials of the client socket and rundir */
1687         if (is_root && set_permissions(config.rundir.value)) {
1688                 retval = -1;
1689                 goto stop_threads;
1690         }
1691
1692         if (!launch_ust_dispatch_thread(&ust_cmd_queue, apps_cmd_pipe[1],
1693                         apps_cmd_notify_pipe[1])) {
1694                 retval = -1;
1695                 goto stop_threads;
1696         }
1697
1698         /* Create thread to manage application registration. */
1699         register_apps_thread = launch_application_registration_thread(
1700                         &ust_cmd_queue);
1701         if (!register_apps_thread) {
1702                 retval = -1;
1703                 goto stop_threads;
1704         }
1705
1706         /* Create thread to manage application socket */
1707         if (!launch_application_management_thread(apps_cmd_pipe[0])) {
1708                 retval = -1;
1709                 goto stop_threads;
1710         }
1711
1712         /* Create thread to manage application notify socket */
1713         if (!launch_application_notification_thread(apps_cmd_notify_pipe[0])) {
1714                 retval = -1;
1715                 goto stop_threads;
1716         }
1717
1718         /* Create agent management thread. */
1719         if (!launch_agent_management_thread()) {
1720                 retval = -1;
1721                 goto stop_threads;
1722         }
1723
1724         /* Don't start this thread if kernel tracing is not requested nor root */
1725         if (is_root && !config.no_kernel) {
1726                 /* Create kernel thread to manage kernel event */
1727                 if (!launch_kernel_management_thread(kernel_poll_pipe[0])) {
1728                         retval = -1;
1729                         goto stop_threads;
1730                 }
1731         }
1732
1733         /* Load sessions. */
1734         ret = config_load_session(config.load_session_path.value,
1735                         NULL, 1, 1, NULL);
1736         if (ret) {
1737                 ERR("Session load failed: %s", error_get_str(ret));
1738                 retval = -1;
1739                 goto stop_threads;
1740         }
1741
1742         /* Initialization completed. */
1743         sessiond_signal_parents();
1744
1745         /*
1746          * This is where we start awaiting program completion (e.g. through
1747          * signal that asks threads to teardown).
1748          */
1749
1750         /* Initiate teardown once activity occurs on the quit pipe. */
1751         sessiond_wait_for_quit_pipe(-1);
1752
1753 stop_threads:
1754         /*
1755          * Ensure that the client thread is no longer accepting new commands,
1756          * which could cause new sessions to be created.
1757          */
1758         if (client_thread) {
1759                 lttng_thread_shutdown(client_thread);
1760                 lttng_thread_put(client_thread);
1761         }
1762
1763         destroy_all_sessions_and_wait();
1764
1765         if (register_apps_thread) {
1766                 lttng_thread_shutdown(register_apps_thread);
1767                 lttng_thread_put(register_apps_thread);
1768         }
1769         lttng_thread_list_shutdown_orphans();
1770
1771         /*
1772          * Wait for all pending call_rcu work to complete before tearing
1773          * down data structures. call_rcu worker may be trying to
1774          * perform lookups in those structures.
1775          */
1776         rcu_barrier();
1777         /*
1778          * sessiond_cleanup() is called when no other thread is running, except
1779          * the ht_cleanup thread, which is needed to destroy the hash tables.
1780          */
1781         rcu_thread_online();
1782         sessiond_cleanup();
1783
1784         if (notification_thread) {
1785                 lttng_thread_shutdown(notification_thread);
1786                 lttng_thread_put(notification_thread);
1787         }
1788
1789         /*
1790          * Ensure all prior call_rcu are done. call_rcu callbacks may push
1791          * hash tables to the ht_cleanup thread. Therefore, we ensure that
1792          * the queue is empty before shutting down the clean-up thread.
1793          */
1794         rcu_barrier();
1795
1796         if (ht_cleanup_thread) {
1797                 lttng_thread_shutdown(ht_cleanup_thread);
1798                 lttng_thread_put(ht_cleanup_thread);
1799         }
1800
1801         rcu_thread_offline();
1802         rcu_unregister_thread();
1803
1804         if (rotation_thread_handle) {
1805                 rotation_thread_handle_destroy(rotation_thread_handle);
1806         }
1807
1808         /*
1809          * After the rotation and timer thread have quit, we can safely destroy
1810          * the rotation_timer_queue.
1811          */
1812         rotation_thread_timer_queue_destroy(rotation_timer_queue);
1813         /*
1814          * The teardown of the notification system is performed after the
1815          * session daemon's teardown in order to allow it to be notified
1816          * of the active session and channels at the moment of the teardown.
1817          */
1818         if (notification_thread_handle) {
1819                 notification_thread_handle_destroy(notification_thread_handle);
1820         }
1821         lttng_pipe_destroy(ust32_channel_monitor_pipe);
1822         lttng_pipe_destroy(ust64_channel_monitor_pipe);
1823         lttng_pipe_destroy(kernel_channel_monitor_pipe);
1824
1825         if (health_sessiond) {
1826                 health_app_destroy(health_sessiond);
1827         }
1828 exit_create_run_as_worker_cleanup:
1829 exit_options:
1830         sessiond_cleanup_lock_file();
1831         sessiond_cleanup_options();
1832
1833 exit_set_signal_handler:
1834         if (!retval) {
1835                 exit(EXIT_SUCCESS);
1836         } else {
1837                 exit(EXIT_FAILURE);
1838         }
1839 }