src/login/logind.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <errno.h>
   4 #include <fcntl.h>
   5 #include <string.h>
   6 #include <unistd.h>
   7
   8 #include "sd-daemon.h"
   9 #include "sd-device.h"
  10
  11 #include "alloc-util.h"
  12 #include "bus-error.h"
  13 #include "bus-util.h"
  14 #include "cgroup-util.h"
  15 #include "def.h"
  16 #include "device-util.h"
  17 #include "dirent-util.h"
  18 #include "fd-util.h"
  19 #include "format-util.h"
  20 #include "fs-util.h"
  21 #include "logind.h"
  22 #include "main-func.h"
  23 #include "parse-util.h"
  24 #include "process-util.h"
  25 #include "selinux-util.h"
  26 #include "signal-util.h"
  27 #include "strv.h"
  28 #include "terminal-util.h"
  29 #include "udev-util.h"
  30
  31 static Manager* manager_unref(Manager *m);
  32 DEFINE_TRIVIAL_CLEANUP_FUNC(Manager*, manager_unref);
  33
  34 static int manager_new(Manager **ret) {
  35         _cleanup_(manager_unrefp) Manager *m = NULL;
  36         int r;
  37
  38         assert(ret);
  39
  40         m = new(Manager, 1);
  41         if (!m)
  42                 return -ENOMEM;
  43
  44         *m = (Manager) {
  45                 .console_active_fd = -1,
  46                 .reserve_vt_fd = -1,
  47                 .idle_action_not_before_usec = now(CLOCK_MONOTONIC),
  48         };
  49
  50         m->devices = hashmap_new(&string_hash_ops);
  51         m->seats = hashmap_new(&string_hash_ops);
  52         m->sessions = hashmap_new(&string_hash_ops);
  53         m->sessions_by_leader = hashmap_new(NULL);
  54         m->users = hashmap_new(NULL);
  55         m->inhibitors = hashmap_new(&string_hash_ops);
  56         m->buttons = hashmap_new(&string_hash_ops);
  57
  58         m->user_units = hashmap_new(&string_hash_ops);
  59         m->session_units = hashmap_new(&string_hash_ops);
  60
  61         if (!m->devices || !m->seats || !m->sessions || !m->sessions_by_leader || !m->users || !m->inhibitors || !m->buttons || !m->user_units || !m->session_units)
  62                 return -ENOMEM;
  63
  64         r = sd_event_default(&m->event);
  65         if (r < 0)
  66                 return r;
  67
  68         r = sd_event_add_signal(m->event, NULL, SIGINT, NULL, NULL);
  69         if (r < 0)
  70                 return r;
  71
  72         r = sd_event_add_signal(m->event, NULL, SIGTERM, NULL, NULL);
  73         if (r < 0)
  74                 return r;
  75
  76         (void) sd_event_set_watchdog(m->event, true);
  77
  78         manager_reset_config(m);
  79
  80         *ret = TAKE_PTR(m);
  81         return 0;
  82 }
  83
  84 static Manager* manager_unref(Manager *m) {
  85         Session *session;
  86         User *u;
  87         Device *d;
  88         Seat *s;
  89         Inhibitor *i;
  90         Button *b;
  91
  92         if (!m)
  93                 return NULL;
  94
  95         while ((session = hashmap_first(m->sessions)))
  96                 session_free(session);
  97
  98         while ((u = hashmap_first(m->users)))
  99                 user_free(u);
 100
 101         while ((d = hashmap_first(m->devices)))
 102                 device_free(d);
 103
 104         while ((s = hashmap_first(m->seats)))
 105                 seat_free(s);
 106
 107         while ((i = hashmap_first(m->inhibitors)))
 108                 inhibitor_free(i);
 109
 110         while ((b = hashmap_first(m->buttons)))
 111                 button_free(b);
 112
 113         hashmap_free(m->devices);
 114         hashmap_free(m->seats);
 115         hashmap_free(m->sessions);
 116         hashmap_free(m->sessions_by_leader);
 117         hashmap_free(m->users);
 118         hashmap_free(m->inhibitors);
 119         hashmap_free(m->buttons);
 120
 121         hashmap_free(m->user_units);
 122         hashmap_free(m->session_units);
 123
 124         sd_event_source_unref(m->idle_action_event_source);
 125         sd_event_source_unref(m->inhibit_timeout_source);
 126         sd_event_source_unref(m->scheduled_shutdown_timeout_source);
 127         sd_event_source_unref(m->nologin_timeout_source);
 128         sd_event_source_unref(m->wall_message_timeout_source);
 129
 130         sd_event_source_unref(m->console_active_event_source);
 131         sd_event_source_unref(m->lid_switch_ignore_event_source);
 132
 133 #if ENABLE_UTMP
 134         sd_event_source_unref(m->utmp_event_source);
 135 #endif
 136
 137         safe_close(m->console_active_fd);
 138
 139         sd_device_monitor_unref(m->device_seat_monitor);
 140         sd_device_monitor_unref(m->device_monitor);
 141         sd_device_monitor_unref(m->device_vcsa_monitor);
 142         sd_device_monitor_unref(m->device_button_monitor);
 143
 144         if (m->unlink_nologin)
 145                 (void) unlink_or_warn("/run/nologin");
 146
 147         bus_verify_polkit_async_registry_free(m->polkit_registry);
 148
 149         sd_bus_flush_close_unref(m->bus);
 150         sd_event_unref(m->event);
 151
 152         safe_close(m->reserve_vt_fd);
 153
 154         strv_free(m->kill_only_users);
 155         strv_free(m->kill_exclude_users);
 156
 157         free(m->scheduled_shutdown_type);
 158         free(m->scheduled_shutdown_tty);
 159         free(m->wall_message);
 160         free(m->action_job);
 161
 162         return mfree(m);
 163 }
 164
 165 static int manager_enumerate_devices(Manager *m) {
 166         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
 167         sd_device *d;
 168         int r;
 169
 170         assert(m);
 171
 172         /* Loads devices from udev and creates seats for them as
 173          * necessary */
 174
 175         r = sd_device_enumerator_new(&e);
 176         if (r < 0)
 177                 return r;
 178
 179         r = sd_device_enumerator_add_match_tag(e, "master-of-seat");
 180         if (r < 0)
 181                 return r;
 182
 183         FOREACH_DEVICE(e, d) {
 184                 int k;
 185
 186                 k = manager_process_seat_device(m, d);
 187                 if (k < 0)
 188                         r = k;
 189         }
 190
 191         return r;
 192 }
 193
 194 static int manager_enumerate_buttons(Manager *m) {
 195         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
 196         sd_device *d;
 197         int r;
 198
 199         assert(m);
 200
 201         /* Loads buttons from udev */
 202
 203         if (manager_all_buttons_ignored(m))
 204                 return 0;
 205
 206         r = sd_device_enumerator_new(&e);
 207         if (r < 0)
 208                 return r;
 209
 210         r = sd_device_enumerator_add_match_subsystem(e, "input", true);
 211         if (r < 0)
 212                 return r;
 213
 214         r = sd_device_enumerator_add_match_tag(e, "power-switch");
 215         if (r < 0)
 216                 return r;
 217
 218         FOREACH_DEVICE(e, d) {
 219                 int k;
 220
 221                 k = manager_process_button_device(m, d);
 222                 if (k < 0)
 223                         r = k;
 224         }
 225
 226         return r;
 227 }
 228
 229 static int manager_enumerate_seats(Manager *m) {
 230         _cleanup_closedir_ DIR *d = NULL;
 231         struct dirent *de;
 232         int r = 0;
 233
 234         assert(m);
 235
 236         /* This loads data about seats stored on disk, but does not
 237          * actually create any seats. Removes data of seats that no
 238          * longer exist. */
 239
 240         d = opendir("/run/systemd/seats");
 241         if (!d) {
 242                 if (errno == ENOENT)
 243                         return 0;
 244
 245                 return log_error_errno(errno, "Failed to open /run/systemd/seats: %m");
 246         }
 247
 248         FOREACH_DIRENT(de, d, return -errno) {
 249                 Seat *s;
 250                 int k;
 251
 252                 if (!dirent_is_file(de))
 253                         continue;
 254
 255                 s = hashmap_get(m->seats, de->d_name);
 256                 if (!s) {
 257                         if (unlinkat(dirfd(d), de->d_name, 0) < 0)
 258                                 log_warning("Failed to remove /run/systemd/seats/%s: %m",
 259                                             de->d_name);
 260                         continue;
 261                 }
 262
 263                 k = seat_load(s);
 264                 if (k < 0)
 265                         r = k;
 266         }
 267
 268         return r;
 269 }
 270
 271 static int manager_enumerate_linger_users(Manager *m) {
 272         _cleanup_closedir_ DIR *d = NULL;
 273         struct dirent *de;
 274         int r = 0;
 275
 276         assert(m);
 277
 278         d = opendir("/var/lib/systemd/linger");
 279         if (!d) {
 280                 if (errno == ENOENT)
 281                         return 0;
 282
 283                 return log_error_errno(errno, "Failed to open /var/lib/systemd/linger/: %m");
 284         }
 285
 286         FOREACH_DIRENT(de, d, return -errno) {
 287                 int k;
 288
 289                 if (!dirent_is_file(de))
 290                         continue;
 291
 292                 k = manager_add_user_by_name(m, de->d_name, NULL);
 293                 if (k < 0) {
 294                         log_notice_errno(k, "Couldn't add lingering user %s: %m", de->d_name);
 295                         r = k;
 296                 }
 297         }
 298
 299         return r;
 300 }
 301
 302 static int manager_enumerate_users(Manager *m) {
 303         _cleanup_closedir_ DIR *d = NULL;
 304         struct dirent *de;
 305         int r, k;
 306
 307         assert(m);
 308
 309         /* Add lingering users */
 310         r = manager_enumerate_linger_users(m);
 311
 312         /* Read in user data stored on disk */
 313         d = opendir("/run/systemd/users");
 314         if (!d) {
 315                 if (errno == ENOENT)
 316                         return 0;
 317
 318                 return log_error_errno(errno, "Failed to open /run/systemd/users: %m");
 319         }
 320
 321         FOREACH_DIRENT(de, d, return -errno) {
 322                 User *u;
 323
 324                 if (!dirent_is_file(de))
 325                         continue;
 326
 327                 k = manager_add_user_by_name(m, de->d_name, &u);
 328                 if (k < 0) {
 329                         log_error_errno(k, "Failed to add user by file name %s: %m", de->d_name);
 330
 331                         r = k;
 332                         continue;
 333                 }
 334
 335                 user_add_to_gc_queue(u);
 336
 337                 k = user_load(u);
 338                 if (k < 0)
 339                         r = k;
 340         }
 341
 342         return r;
 343 }
 344
 345 static int parse_fdname(const char *fdname, char **session_id, dev_t *dev) {
 346         _cleanup_strv_free_ char **parts = NULL;
 347         _cleanup_free_ char *id = NULL;
 348         unsigned major, minor;
 349         int r;
 350
 351         parts = strv_split(fdname, "-");
 352         if (!parts)
 353                 return -ENOMEM;
 354         if (strv_length(parts) != 5)
 355                 return -EINVAL;
 356
 357         if (!streq(parts[0], "session"))
 358                 return -EINVAL;
 359
 360         id = strdup(parts[1]);
 361         if (!id)
 362                 return -ENOMEM;
 363
 364         if (!streq(parts[2], "device"))
 365                 return -EINVAL;
 366
 367         r = safe_atou(parts[3], &major);
 368         if (r < 0)
 369                 return r;
 370         r = safe_atou(parts[4], &minor);
 371         if (r < 0)
 372                 return r;
 373
 374         *dev = makedev(major, minor);
 375         *session_id = TAKE_PTR(id);
 376
 377         return 0;
 378 }
 379
 380 static int deliver_fd(Manager *m, const char *fdname, int fd) {
 381         _cleanup_free_ char *id = NULL;
 382         SessionDevice *sd;
 383         struct stat st;
 384         Session *s;
 385         dev_t dev;
 386         int r;
 387
 388         assert(m);
 389         assert(fd >= 0);
 390
 391         r = parse_fdname(fdname, &id, &dev);
 392         if (r < 0)
 393                 return log_debug_errno(r, "Failed to parse fd name %s: %m", fdname);
 394
 395         s = hashmap_get(m->sessions, id);
 396         if (!s)
 397                 /* If the session doesn't exist anymore, the associated session device attached to this fd
 398                  * doesn't either. Let's simply close this fd. */
 399                 return log_debug_errno(SYNTHETIC_ERRNO(ENXIO), "Failed to attach fd for unknown session: %s", id);
 400
 401         if (fstat(fd, &st) < 0)
 402                 /* The device is allowed to go away at a random point, in which case fstat() failing is
 403                  * expected. */
 404                 return log_debug_errno(errno, "Failed to stat device fd for session %s: %m", id);
 405
 406         if (!S_ISCHR(st.st_mode) || st.st_rdev != dev)
 407                 return log_debug_errno(SYNTHETIC_ERRNO(ENODEV), "Device fd doesn't point to the expected character device node");
 408
 409         sd = hashmap_get(s->devices, &dev);
 410         if (!sd)
 411                 /* Weird, we got an fd for a session device which wasn't recorded in the session state
 412                  * file... */
 413                 return log_warning_errno(SYNTHETIC_ERRNO(ENODEV), "Got fd for missing session device [%u:%u] in session %s",
 414                                          major(dev), minor(dev), s->id);
 415
 416         log_debug("Attaching fd to session device [%u:%u] for session %s",
 417                   major(dev), minor(dev), s->id);
 418
 419         session_device_attach_fd(sd, fd, s->was_active);
 420         return 0;
 421 }
 422
 423 static int manager_attach_fds(Manager *m) {
 424         _cleanup_strv_free_ char **fdnames = NULL;
 425         int n;
 426
 427         /* Upon restart, PID1 will send us back all fds of session devices that we previously opened. Each
 428          * file descriptor is associated with a given session. The session ids are passed through FDNAMES. */
 429
 430         n = sd_listen_fds_with_names(true, &fdnames);
 431         if (n < 0)
 432                 return log_warning_errno(n, "Failed to acquire passed fd list: %m");
 433         if (n == 0)
 434                 return 0;
 435
 436         for (int i = 0; i < n; i++) {
 437                 int fd = SD_LISTEN_FDS_START + i;
 438
 439                 if (deliver_fd(m, fdnames[i], fd) >= 0)
 440                         continue;
 441
 442                 /* Hmm, we couldn't deliver the fd to any session device object? If so, let's close the fd */
 443                 safe_close(fd);
 444
 445                 /* Remove from fdstore as well */
 446                 (void) sd_notifyf(false,
 447                                   "FDSTOREREMOVE=1\n"
 448                                   "FDNAME=%s", fdnames[i]);
 449         }
 450
 451         return 0;
 452 }
 453
 454 static int manager_enumerate_sessions(Manager *m) {
 455         _cleanup_closedir_ DIR *d = NULL;
 456         struct dirent *de;
 457         int r = 0, k;
 458
 459         assert(m);
 460
 461         /* Read in session data stored on disk */
 462         d = opendir("/run/systemd/sessions");
 463         if (!d) {
 464                 if (errno == ENOENT)
 465                         return 0;
 466
 467                 return log_error_errno(errno, "Failed to open /run/systemd/sessions: %m");
 468         }
 469
 470         FOREACH_DIRENT(de, d, return -errno) {
 471                 struct Session *s;
 472
 473                 if (!dirent_is_file(de))
 474                         continue;
 475
 476                 if (!session_id_valid(de->d_name)) {
 477                         log_warning("Invalid session file name '%s', ignoring.", de->d_name);
 478                         r = -EINVAL;
 479                         continue;
 480                 }
 481
 482                 k = manager_add_session(m, de->d_name, &s);
 483                 if (k < 0) {
 484                         log_error_errno(k, "Failed to add session by file name %s: %m", de->d_name);
 485                         r = k;
 486                         continue;
 487                 }
 488
 489                 session_add_to_gc_queue(s);
 490
 491                 k = session_load(s);
 492                 if (k < 0)
 493                         r = k;
 494         }
 495
 496         /* We might be restarted and PID1 could have sent us back the session device fds we previously
 497          * saved. */
 498         (void) manager_attach_fds(m);
 499
 500         return r;
 501 }
 502
 503 static int manager_enumerate_inhibitors(Manager *m) {
 504         _cleanup_closedir_ DIR *d = NULL;
 505         struct dirent *de;
 506         int r = 0;
 507
 508         assert(m);
 509
 510         d = opendir("/run/systemd/inhibit");
 511         if (!d) {
 512                 if (errno == ENOENT)
 513                         return 0;
 514
 515                 return log_error_errno(errno, "Failed to open /run/systemd/inhibit: %m");
 516         }
 517
 518         FOREACH_DIRENT(de, d, return -errno) {
 519                 int k;
 520                 Inhibitor *i;
 521
 522                 if (!dirent_is_file(de))
 523                         continue;
 524
 525                 k = manager_add_inhibitor(m, de->d_name, &i);
 526                 if (k < 0) {
 527                         log_notice_errno(k, "Couldn't add inhibitor %s: %m", de->d_name);
 528                         r = k;
 529                         continue;
 530                 }
 531
 532                 k = inhibitor_load(i);
 533                 if (k < 0)
 534                         r = k;
 535         }
 536
 537         return r;
 538 }
 539
 540 static int manager_dispatch_seat_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
 541         Manager *m = userdata;
 542
 543         assert(m);
 544         assert(device);
 545
 546         manager_process_seat_device(m, device);
 547         return 0;
 548 }
 549
 550 static int manager_dispatch_device_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
 551         Manager *m = userdata;
 552
 553         assert(m);
 554         assert(device);
 555
 556         manager_process_seat_device(m, device);
 557         return 0;
 558 }
 559
 560 static int manager_dispatch_vcsa_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
 561         Manager *m = userdata;
 562         const char *name;
 563
 564         assert(m);
 565         assert(device);
 566
 567         /* Whenever a VCSA device is removed try to reallocate our
 568          * VTs, to make sure our auto VTs never go away. */
 569
 570         if (sd_device_get_sysname(device, &name) >= 0 &&
 571             startswith(name, "vcsa") &&
 572             device_for_action(device, DEVICE_ACTION_REMOVE))
 573                 seat_preallocate_vts(m->seat0);
 574
 575         return 0;
 576 }
 577
 578 static int manager_dispatch_button_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
 579         Manager *m = userdata;
 580
 581         assert(m);
 582         assert(device);
 583
 584         manager_process_button_device(m, device);
 585         return 0;
 586 }
 587
 588 static int manager_dispatch_console(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
 589         Manager *m = userdata;
 590
 591         assert(m);
 592         assert(m->seat0);
 593         assert(m->console_active_fd == fd);
 594
 595         seat_read_active_vt(m->seat0);
 596         return 0;
 597 }
 598
 599 static int manager_reserve_vt(Manager *m) {
 600         _cleanup_free_ char *p = NULL;
 601
 602         assert(m);
 603
 604         if (m->reserve_vt <= 0)
 605                 return 0;
 606
 607         if (asprintf(&p, "/dev/tty%u", m->reserve_vt) < 0)
 608                 return log_oom();
 609
 610         m->reserve_vt_fd = open(p, O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK);
 611         if (m->reserve_vt_fd < 0) {
 612
 613                 /* Don't complain on VT-less systems */
 614                 if (errno != ENOENT)
 615                         log_warning_errno(errno, "Failed to pin reserved VT: %m");
 616                 return -errno;
 617         }
 618
 619         return 0;
 620 }
 621
 622 static int manager_connect_bus(Manager *m) {
 623         int r;
 624
 625         assert(m);
 626         assert(!m->bus);
 627
 628         r = sd_bus_default_system(&m->bus);
 629         if (r < 0)
 630                 return log_error_errno(r, "Failed to connect to system bus: %m");
 631
 632         r = sd_bus_add_object_vtable(m->bus, NULL, "/org/freedesktop/login1", "org.freedesktop.login1.Manager", manager_vtable, m);
 633         if (r < 0)
 634                 return log_error_errno(r, "Failed to add manager object vtable: %m");
 635
 636         r = sd_bus_add_fallback_vtable(m->bus, NULL, "/org/freedesktop/login1/seat", "org.freedesktop.login1.Seat", seat_vtable, seat_object_find, m);
 637         if (r < 0)
 638                 return log_error_errno(r, "Failed to add seat object vtable: %m");
 639
 640         r = sd_bus_add_node_enumerator(m->bus, NULL, "/org/freedesktop/login1/seat", seat_node_enumerator, m);
 641         if (r < 0)
 642                 return log_error_errno(r, "Failed to add seat enumerator: %m");
 643
 644         r = sd_bus_add_fallback_vtable(m->bus, NULL, "/org/freedesktop/login1/session", "org.freedesktop.login1.Session", session_vtable, session_object_find, m);
 645         if (r < 0)
 646                 return log_error_errno(r, "Failed to add session object vtable: %m");
 647
 648         r = sd_bus_add_node_enumerator(m->bus, NULL, "/org/freedesktop/login1/session", session_node_enumerator, m);
 649         if (r < 0)
 650                 return log_error_errno(r, "Failed to add session enumerator: %m");
 651
 652         r = sd_bus_add_fallback_vtable(m->bus, NULL, "/org/freedesktop/login1/user", "org.freedesktop.login1.User", user_vtable, user_object_find, m);
 653         if (r < 0)
 654                 return log_error_errno(r, "Failed to add user object vtable: %m");
 655
 656         r = sd_bus_add_node_enumerator(m->bus, NULL, "/org/freedesktop/login1/user", user_node_enumerator, m);
 657         if (r < 0)
 658                 return log_error_errno(r, "Failed to add user enumerator: %m");
 659
 660         r = sd_bus_match_signal_async(
 661                         m->bus,
 662                         NULL,
 663                         "org.freedesktop.systemd1",
 664                         "/org/freedesktop/systemd1",
 665                         "org.freedesktop.systemd1.Manager",
 666                         "JobRemoved",
 667                         match_job_removed, NULL, m);
 668         if (r < 0)
 669                 return log_error_errno(r, "Failed to request match for JobRemoved: %m");
 670
 671         r = sd_bus_match_signal_async(
 672                         m->bus,
 673                         NULL,
 674                         "org.freedesktop.systemd1",
 675                         "/org/freedesktop/systemd1",
 676                         "org.freedesktop.systemd1.Manager",
 677                         "UnitRemoved",
 678                         match_unit_removed, NULL, m);
 679         if (r < 0)
 680                 return log_error_errno(r, "Failed to request match for UnitRemoved: %m");
 681
 682         r = sd_bus_match_signal_async(
 683                         m->bus,
 684                         NULL,
 685                         "org.freedesktop.systemd1",
 686                         NULL,
 687                         "org.freedesktop.DBus.Properties",
 688                         "PropertiesChanged",
 689                         match_properties_changed, NULL, m);
 690         if (r < 0)
 691                 return log_error_errno(r, "Failed to request match for PropertiesChanged: %m");
 692
 693         r = sd_bus_match_signal_async(
 694                         m->bus,
 695                         NULL,
 696                         "org.freedesktop.systemd1",
 697                         "/org/freedesktop/systemd1",
 698                         "org.freedesktop.systemd1.Manager",
 699                         "Reloading",
 700                         match_reloading, NULL, m);
 701         if (r < 0)
 702                 return log_error_errno(r, "Failed to request match for Reloading: %m");
 703
 704         r = sd_bus_call_method_async(
 705                         m->bus,
 706                         NULL,
 707                         "org.freedesktop.systemd1",
 708                         "/org/freedesktop/systemd1",
 709                         "org.freedesktop.systemd1.Manager",
 710                         "Subscribe",
 711                         NULL, NULL,
 712                         NULL);
 713         if (r < 0)
 714                 return log_error_errno(r, "Failed to enable subscription: %m");
 715
 716         r = sd_bus_request_name_async(m->bus, NULL, "org.freedesktop.login1", 0, NULL, NULL);
 717         if (r < 0)
 718                 return log_error_errno(r, "Failed to request name: %m");
 719
 720         r = sd_bus_attach_event(m->bus, m->event, SD_EVENT_PRIORITY_NORMAL);
 721         if (r < 0)
 722                 return log_error_errno(r, "Failed to attach bus to event loop: %m");
 723
 724         return 0;
 725 }
 726
 727 static int manager_vt_switch(sd_event_source *src, const struct signalfd_siginfo *si, void *data) {
 728         Manager *m = data;
 729         Session *active, *iter;
 730
 731         /*
 732          * We got a VT-switch signal and we have to acknowledge it immediately.
 733          * Preferably, we'd just use m->seat0->active->vtfd, but unfortunately,
 734          * old user-space might run multiple sessions on a single VT, *sigh*.
 735          * Therefore, we have to iterate all sessions and find one with a vtfd
 736          * on the requested VT.
 737          * As only VTs with active controllers have VT_PROCESS set, our current
 738          * notion of the active VT might be wrong (for instance if the switch
 739          * happens while we setup VT_PROCESS). Therefore, read the current VT
 740          * first and then use s->active->vtnr as reference. Note that this is
 741          * not racy, as no further VT-switch can happen as long as we're in
 742          * synchronous VT_PROCESS mode.
 743          */
 744
 745         assert(m->seat0);
 746         seat_read_active_vt(m->seat0);
 747
 748         active = m->seat0->active;
 749         if (!active || active->vtnr < 1) {
 750                 _cleanup_close_ int fd = -1;
 751                 int r;
 752
 753                 /* We are requested to acknowledge the VT-switch signal by the kernel but
 754                  * there's no registered sessions for the current VT. Normally this
 755                  * shouldn't happen but something wrong might have happened when we tried
 756                  * to release the VT. Better be safe than sorry, and try to release the VT
 757                  * one more time otherwise the user will be locked with the current VT. */
 758
 759                 log_warning("Received VT_PROCESS signal without a registered session, restoring VT.");
 760
 761                 /* At this point we only have the kernel mapping for referring to the
 762                  * current VT. */
 763                 fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK);
 764                 if (fd < 0) {
 765                         log_warning_errno(fd, "Failed to open, ignoring: %m");
 766                         return 0;
 767                 }
 768
 769                 r = vt_release(fd, true);
 770                 if (r < 0)
 771                         log_warning_errno(r, "Failed to release VT, ignoring: %m");
 772
 773                 return 0;
 774         }
 775
 776         if (active->vtfd >= 0) {
 777                 session_leave_vt(active);
 778         } else {
 779                 LIST_FOREACH(sessions_by_seat, iter, m->seat0->sessions) {
 780                         if (iter->vtnr == active->vtnr && iter->vtfd >= 0) {
 781                                 session_leave_vt(iter);
 782                                 break;
 783                         }
 784                 }
 785         }
 786
 787         return 0;
 788 }
 789
 790 static int manager_connect_console(Manager *m) {
 791         int r;
 792
 793         assert(m);
 794         assert(m->console_active_fd < 0);
 795
 796         /* On certain systems (such as S390, Xen, and containers) /dev/tty0 does not exist (as there is no VC), so
 797          * don't fail if we can't open it. */
 798
 799         if (access("/dev/tty0", F_OK) < 0)
 800                 return 0;
 801
 802         m->console_active_fd = open("/sys/class/tty/tty0/active", O_RDONLY|O_NOCTTY|O_CLOEXEC);
 803         if (m->console_active_fd < 0) {
 804
 805                 /* On some systems /dev/tty0 may exist even though /sys/class/tty/tty0 does not. These are broken, but
 806                  * common. Let's complain but continue anyway. */
 807                 if (errno == ENOENT) {
 808                         log_warning_errno(errno, "System has /dev/tty0 but not /sys/class/tty/tty0/active which is broken, ignoring: %m");
 809                         return 0;
 810                 }
 811
 812                 return log_error_errno(errno, "Failed to open /sys/class/tty/tty0/active: %m");
 813         }
 814
 815         r = sd_event_add_io(m->event, &m->console_active_event_source, m->console_active_fd, 0, manager_dispatch_console, m);
 816         if (r < 0)
 817                 return log_error_errno(r, "Failed to watch foreground console: %m");
 818
 819         /*
 820          * SIGRTMIN is used as global VT-release signal, SIGRTMIN + 1 is used
 821          * as VT-acquire signal. We ignore any acquire-events (yes, we still
 822          * have to provide a valid signal-number for it!) and acknowledge all
 823          * release events immediately.
 824          */
 825
 826         if (SIGRTMIN + 1 > SIGRTMAX)
 827                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 828                                        "Not enough real-time signals available: %u-%u",
 829                                        SIGRTMIN, SIGRTMAX);
 830
 831         assert_se(ignore_signals(SIGRTMIN + 1, -1) >= 0);
 832         assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGRTMIN, -1) >= 0);
 833
 834         r = sd_event_add_signal(m->event, NULL, SIGRTMIN, manager_vt_switch, m);
 835         if (r < 0)
 836                 return log_error_errno(r, "Failed to subscribe to signal: %m");
 837
 838         return 0;
 839 }
 840
 841 static int manager_connect_udev(Manager *m) {
 842         int r;
 843
 844         assert(m);
 845         assert(!m->device_seat_monitor);
 846         assert(!m->device_monitor);
 847         assert(!m->device_vcsa_monitor);
 848         assert(!m->device_button_monitor);
 849
 850         r = sd_device_monitor_new(&m->device_seat_monitor);
 851         if (r < 0)
 852                 return r;
 853
 854         r = sd_device_monitor_filter_add_match_tag(m->device_seat_monitor, "master-of-seat");
 855         if (r < 0)
 856                 return r;
 857
 858         r = sd_device_monitor_attach_event(m->device_seat_monitor, m->event);
 859         if (r < 0)
 860                 return r;
 861
 862         r = sd_device_monitor_start(m->device_seat_monitor, manager_dispatch_seat_udev, m);
 863         if (r < 0)
 864                 return r;
 865
 866         (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_seat_monitor), "logind-seat-monitor");
 867
 868         r = sd_device_monitor_new(&m->device_monitor);
 869         if (r < 0)
 870                 return r;
 871
 872         r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_monitor, "input", NULL);
 873         if (r < 0)
 874                 return r;
 875
 876         r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_monitor, "graphics", NULL);
 877         if (r < 0)
 878                 return r;
 879
 880         r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_monitor, "drm", NULL);
 881         if (r < 0)
 882                 return r;
 883
 884         r = sd_device_monitor_attach_event(m->device_monitor, m->event);
 885         if (r < 0)
 886                 return r;
 887
 888         r = sd_device_monitor_start(m->device_monitor, manager_dispatch_device_udev, m);
 889         if (r < 0)
 890                 return r;
 891
 892         (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_monitor), "logind-device-monitor");
 893
 894         /* Don't watch keys if nobody cares */
 895         if (!manager_all_buttons_ignored(m)) {
 896                 r = sd_device_monitor_new(&m->device_button_monitor);
 897                 if (r < 0)
 898                         return r;
 899
 900                 r = sd_device_monitor_filter_add_match_tag(m->device_button_monitor, "power-switch");
 901                 if (r < 0)
 902                         return r;
 903
 904                 r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_button_monitor, "input", NULL);
 905                 if (r < 0)
 906                         return r;
 907
 908                 r = sd_device_monitor_attach_event(m->device_button_monitor, m->event);
 909                 if (r < 0)
 910                         return r;
 911
 912                 r = sd_device_monitor_start(m->device_button_monitor, manager_dispatch_button_udev, m);
 913                 if (r < 0)
 914                         return r;
 915
 916                 (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_button_monitor), "logind-button-monitor");
 917         }
 918
 919         /* Don't bother watching VCSA devices, if nobody cares */
 920         if (m->n_autovts > 0 && m->console_active_fd >= 0) {
 921
 922                 r = sd_device_monitor_new(&m->device_vcsa_monitor);
 923                 if (r < 0)
 924                         return r;
 925
 926                 r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_vcsa_monitor, "vc", NULL);
 927                 if (r < 0)
 928                         return r;
 929
 930                 r = sd_device_monitor_attach_event(m->device_vcsa_monitor, m->event);
 931                 if (r < 0)
 932                         return r;
 933
 934                 r = sd_device_monitor_start(m->device_vcsa_monitor, manager_dispatch_vcsa_udev, m);
 935                 if (r < 0)
 936                         return r;
 937
 938                 (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_vcsa_monitor), "logind-vcsa-monitor");
 939         }
 940
 941         return 0;
 942 }
 943
 944 static void manager_gc(Manager *m, bool drop_not_started) {
 945         Seat *seat;
 946         Session *session;
 947         User *user;
 948
 949         assert(m);
 950
 951         while ((seat = m->seat_gc_queue)) {
 952                 LIST_REMOVE(gc_queue, m->seat_gc_queue, seat);
 953                 seat->in_gc_queue = false;
 954
 955                 if (seat_may_gc(seat, drop_not_started)) {
 956                         seat_stop(seat, false);
 957                         seat_free(seat);
 958                 }
 959         }
 960
 961         while ((session = m->session_gc_queue)) {
 962                 LIST_REMOVE(gc_queue, m->session_gc_queue, session);
 963                 session->in_gc_queue = false;
 964
 965                 /* First, if we are not closing yet, initiate stopping */
 966                 if (session_may_gc(session, drop_not_started) &&
 967                     session_get_state(session) != SESSION_CLOSING)
 968                         (void) session_stop(session, false);
 969
 970                 /* Normally, this should make the session referenced
 971                  * again, if it doesn't then let's get rid of it
 972                  * immediately */
 973                 if (session_may_gc(session, drop_not_started)) {
 974                         (void) session_finalize(session);
 975                         session_free(session);
 976                 }
 977         }
 978
 979         while ((user = m->user_gc_queue)) {
 980                 LIST_REMOVE(gc_queue, m->user_gc_queue, user);
 981                 user->in_gc_queue = false;
 982
 983                 /* First step: queue stop jobs */
 984                 if (user_may_gc(user, drop_not_started))
 985                         (void) user_stop(user, false);
 986
 987                 /* Second step: finalize user */
 988                 if (user_may_gc(user, drop_not_started)) {
 989                         (void) user_finalize(user);
 990                         user_free(user);
 991                 }
 992         }
 993 }
 994
 995 static int manager_dispatch_idle_action(sd_event_source *s, uint64_t t, void *userdata) {
 996         Manager *m = userdata;
 997         struct dual_timestamp since;
 998         usec_t n, elapse;
 999         int r;
1000
1001         assert(m);
1002
1003         if (m->idle_action == HANDLE_IGNORE ||
1004             m->idle_action_usec <= 0)
1005                 return 0;
1006
1007         n = now(CLOCK_MONOTONIC);
1008
1009         r = manager_get_idle_hint(m, &since);
1010         if (r <= 0)
1011                 /* Not idle. Let's check if after a timeout it might be idle then. */
1012                 elapse = n + m->idle_action_usec;
1013         else {
1014                 /* Idle! Let's see if it's time to do something, or if
1015                  * we shall sleep for longer. */
1016
1017                 if (n >= since.monotonic + m->idle_action_usec &&
1018                     (m->idle_action_not_before_usec <= 0 || n >= m->idle_action_not_before_usec + m->idle_action_usec)) {
1019                         log_info("System idle. Taking action.");
1020
1021                         manager_handle_action(m, 0, m->idle_action, false, false);
1022                         m->idle_action_not_before_usec = n;
1023                 }
1024
1025                 elapse = MAX(since.monotonic, m->idle_action_not_before_usec) + m->idle_action_usec;
1026         }
1027
1028         if (!m->idle_action_event_source) {
1029
1030                 r = sd_event_add_time(
1031                                 m->event,
1032                                 &m->idle_action_event_source,
1033                                 CLOCK_MONOTONIC,
1034                                 elapse, USEC_PER_SEC*30,
1035                                 manager_dispatch_idle_action, m);
1036                 if (r < 0)
1037                         return log_error_errno(r, "Failed to add idle event source: %m");
1038
1039                 r = sd_event_source_set_priority(m->idle_action_event_source, SD_EVENT_PRIORITY_IDLE+10);
1040                 if (r < 0)
1041                         return log_error_errno(r, "Failed to set idle event source priority: %m");
1042         } else {
1043                 r = sd_event_source_set_time(m->idle_action_event_source, elapse);
1044                 if (r < 0)
1045                         return log_error_errno(r, "Failed to set idle event timer: %m");
1046
1047                 r = sd_event_source_set_enabled(m->idle_action_event_source, SD_EVENT_ONESHOT);
1048                 if (r < 0)
1049                         return log_error_errno(r, "Failed to enable idle event timer: %m");
1050         }
1051
1052         return 0;
1053 }
1054
1055 static int manager_dispatch_reload_signal(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
1056         Manager *m = userdata;
1057         int r;
1058
1059         manager_reset_config(m);
1060         r = manager_parse_config_file(m);
1061         if (r < 0)
1062                 log_warning_errno(r, "Failed to parse config file, using defaults: %m");
1063         else
1064                 log_info("Config file reloaded.");
1065
1066         return 0;
1067 }
1068
1069 static int manager_startup(Manager *m) {
1070         int r;
1071         Seat *seat;
1072         Session *session;
1073         User *user;
1074         Button *button;
1075         Inhibitor *inhibitor;
1076         Iterator i;
1077
1078         assert(m);
1079
1080         r = sd_event_add_signal(m->event, NULL, SIGHUP, manager_dispatch_reload_signal, m);
1081         if (r < 0)
1082                 return log_error_errno(r, "Failed to register SIGHUP handler: %m");
1083
1084         /* Connect to utmp */
1085         manager_connect_utmp(m);
1086
1087         /* Connect to console */
1088         r = manager_connect_console(m);
1089         if (r < 0)
1090                 return r;
1091
1092         /* Connect to udev */
1093         r = manager_connect_udev(m);
1094         if (r < 0)
1095                 return log_error_errno(r, "Failed to create udev watchers: %m");
1096
1097         /* Connect to the bus */
1098         r = manager_connect_bus(m);
1099         if (r < 0)
1100                 return r;
1101
1102         /* Instantiate magic seat 0 */
1103         r = manager_add_seat(m, "seat0", &m->seat0);
1104         if (r < 0)
1105                 return log_error_errno(r, "Failed to add seat0: %m");
1106
1107         r = manager_set_lid_switch_ignore(m, 0 + m->holdoff_timeout_usec);
1108         if (r < 0)
1109                 log_warning_errno(r, "Failed to set up lid switch ignore event source: %m");
1110
1111         /* Deserialize state */
1112         r = manager_enumerate_devices(m);
1113         if (r < 0)
1114                 log_warning_errno(r, "Device enumeration failed: %m");
1115
1116         r = manager_enumerate_seats(m);
1117         if (r < 0)
1118                 log_warning_errno(r, "Seat enumeration failed: %m");
1119
1120         r = manager_enumerate_users(m);
1121         if (r < 0)
1122                 log_warning_errno(r, "User enumeration failed: %m");
1123
1124         r = manager_enumerate_sessions(m);
1125         if (r < 0)
1126                 log_warning_errno(r, "Session enumeration failed: %m");
1127
1128         r = manager_enumerate_inhibitors(m);
1129         if (r < 0)
1130                 log_warning_errno(r, "Inhibitor enumeration failed: %m");
1131
1132         r = manager_enumerate_buttons(m);
1133         if (r < 0)
1134                 log_warning_errno(r, "Button enumeration failed: %m");
1135
1136         /* Remove stale objects before we start them */
1137         manager_gc(m, false);
1138
1139         /* Reserve the special reserved VT */
1140         manager_reserve_vt(m);
1141
1142         /* Read in utmp if it exists */
1143         manager_read_utmp(m);
1144
1145         /* And start everything */
1146         HASHMAP_FOREACH(seat, m->seats, i)
1147                 (void) seat_start(seat);
1148
1149         HASHMAP_FOREACH(user, m->users, i)
1150                 (void) user_start(user);
1151
1152         HASHMAP_FOREACH(session, m->sessions, i)
1153                 (void) session_start(session, NULL, NULL);
1154
1155         HASHMAP_FOREACH(inhibitor, m->inhibitors, i)
1156                 inhibitor_start(inhibitor);
1157
1158         HASHMAP_FOREACH(button, m->buttons, i)
1159                 button_check_switches(button);
1160
1161         manager_dispatch_idle_action(NULL, 0, m);
1162
1163         return 0;
1164 }
1165
1166 static int manager_run(Manager *m) {
1167         int r;
1168
1169         assert(m);
1170
1171         for (;;) {
1172                 r = sd_event_get_state(m->event);
1173                 if (r < 0)
1174                         return r;
1175                 if (r == SD_EVENT_FINISHED)
1176                         return 0;
1177
1178                 manager_gc(m, true);
1179
1180                 r = manager_dispatch_delayed(m, false);
1181                 if (r < 0)
1182                         return r;
1183                 if (r > 0)
1184                         continue;
1185
1186                 r = sd_event_run(m->event, (uint64_t) -1);
1187                 if (r < 0)
1188                         return r;
1189         }
1190 }
1191
1192 static int run(int argc, char *argv[]) {
1193         _cleanup_(manager_unrefp) Manager *m = NULL;
1194         int r;
1195
1196         log_set_facility(LOG_AUTH);
1197         log_setup_service();
1198
1199         umask(0022);
1200
1201         if (argc != 1) {
1202                 log_error("This program takes no arguments.");
1203                 return -EINVAL;
1204         }
1205
1206         r = mac_selinux_init();
1207         if (r < 0)
1208                 return log_error_errno(r, "Could not initialize labelling: %m");
1209
1210         /* Always create the directories people can create inotify watches in. Note that some applications might check
1211          * for the existence of /run/systemd/seats/ to determine whether logind is available, so please always make
1212          * sure these directories are created early on and unconditionally. */
1213         (void) mkdir_label("/run/systemd/seats", 0755);
1214         (void) mkdir_label("/run/systemd/users", 0755);
1215         (void) mkdir_label("/run/systemd/sessions", 0755);
1216
1217         assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGHUP, SIGTERM, SIGINT, -1) >= 0);
1218
1219         r = manager_new(&m);
1220         if (r < 0)
1221                 return log_error_errno(r, "Failed to allocate manager object: %m");
1222
1223         (void) manager_parse_config_file(m);
1224
1225         r = manager_startup(m);
1226         if (r < 0)
1227                 return log_error_errno(r, "Failed to fully start up daemon: %m");
1228
1229         log_debug("systemd-logind running as pid "PID_FMT, getpid_cached());
1230         (void) sd_notify(false,
1231                          "READY=1\n"
1232                          "STATUS=Processing requests...");
1233
1234         r = manager_run(m);
1235
1236         log_debug("systemd-logind stopped as pid "PID_FMT, getpid_cached());
1237         (void) sd_notify(false,
1238                          "STOPPING=1\n"
1239                          "STATUS=Shutting down...");
1240
1241         return r;
1242 }
1243
1244 DEFINE_MAIN_FUNCTION(run);