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-dbus.h"
  22 #include "logind-seat-dbus.h"
  23 #include "logind-session-dbus.h"
  24 #include "logind-user-dbus.h"
  25 #include "logind.h"
  26 #include "main-func.h"
  27 #include "parse-util.h"
  28 #include "process-util.h"
  29 #include "selinux-util.h"
  30 #include "signal-util.h"
  31 #include "strv.h"
  32 #include "terminal-util.h"
  33 #include "udev-util.h"
  34
  35 static Manager* manager_unref(Manager *m);
  36 DEFINE_TRIVIAL_CLEANUP_FUNC(Manager*, manager_unref);
  37
  38 static int manager_new(Manager **ret) {
  39         _cleanup_(manager_unrefp) Manager *m = NULL;
  40         int r;
  41
  42         assert(ret);
  43
  44         m = new(Manager, 1);
  45         if (!m)
  46                 return -ENOMEM;
  47
  48         *m = (Manager) {
  49                 .console_active_fd = -1,
  50                 .reserve_vt_fd = -1,
  51                 .idle_action_not_before_usec = now(CLOCK_MONOTONIC),
  52         };
  53
  54         m->devices = hashmap_new(&string_hash_ops);
  55         m->seats = hashmap_new(&string_hash_ops);
  56         m->sessions = hashmap_new(&string_hash_ops);
  57         m->sessions_by_leader = hashmap_new(NULL);
  58         m->users = hashmap_new(NULL);
  59         m->inhibitors = hashmap_new(&string_hash_ops);
  60         m->buttons = hashmap_new(&string_hash_ops);
  61
  62         m->user_units = hashmap_new(&string_hash_ops);
  63         m->session_units = hashmap_new(&string_hash_ops);
  64
  65         if (!m->devices || !m->seats || !m->sessions || !m->sessions_by_leader || !m->users || !m->inhibitors || !m->buttons || !m->user_units || !m->session_units)
  66                 return -ENOMEM;
  67
  68         r = sd_event_default(&m->event);
  69         if (r < 0)
  70                 return r;
  71
  72         r = sd_event_add_signal(m->event, NULL, SIGINT, NULL, NULL);
  73         if (r < 0)
  74                 return r;
  75
  76         r = sd_event_add_signal(m->event, NULL, SIGTERM, NULL, NULL);
  77         if (r < 0)
  78                 return r;
  79
  80         (void) sd_event_set_watchdog(m->event, true);
  81
  82         manager_reset_config(m);
  83
  84         *ret = TAKE_PTR(m);
  85         return 0;
  86 }
  87
  88 static Manager* manager_unref(Manager *m) {
  89         Session *session;
  90         User *u;
  91         Device *d;
  92         Seat *s;
  93         Inhibitor *i;
  94         Button *b;
  95
  96         if (!m)
  97                 return NULL;
  98
  99         while ((session = hashmap_first(m->sessions)))
 100                 session_free(session);
 101
 102         while ((u = hashmap_first(m->users)))
 103                 user_free(u);
 104
 105         while ((d = hashmap_first(m->devices)))
 106                 device_free(d);
 107
 108         while ((s = hashmap_first(m->seats)))
 109                 seat_free(s);
 110
 111         while ((i = hashmap_first(m->inhibitors)))
 112                 inhibitor_free(i);
 113
 114         while ((b = hashmap_first(m->buttons)))
 115                 button_free(b);
 116
 117         hashmap_free(m->devices);
 118         hashmap_free(m->seats);
 119         hashmap_free(m->sessions);
 120         hashmap_free(m->sessions_by_leader);
 121         hashmap_free(m->users);
 122         hashmap_free(m->inhibitors);
 123         hashmap_free(m->buttons);
 124         hashmap_free(m->brightness_writers);
 125
 126         hashmap_free(m->user_units);
 127         hashmap_free(m->session_units);
 128
 129         sd_event_source_unref(m->idle_action_event_source);
 130         sd_event_source_unref(m->inhibit_timeout_source);
 131         sd_event_source_unref(m->scheduled_shutdown_timeout_source);
 132         sd_event_source_unref(m->nologin_timeout_source);
 133         sd_event_source_unref(m->wall_message_timeout_source);
 134
 135         sd_event_source_unref(m->console_active_event_source);
 136         sd_event_source_unref(m->lid_switch_ignore_event_source);
 137
 138 #if ENABLE_UTMP
 139         sd_event_source_unref(m->utmp_event_source);
 140 #endif
 141
 142         safe_close(m->console_active_fd);
 143
 144         sd_device_monitor_unref(m->device_seat_monitor);
 145         sd_device_monitor_unref(m->device_monitor);
 146         sd_device_monitor_unref(m->device_vcsa_monitor);
 147         sd_device_monitor_unref(m->device_button_monitor);
 148
 149         if (m->unlink_nologin)
 150                 (void) unlink_or_warn("/run/nologin");
 151
 152         bus_verify_polkit_async_registry_free(m->polkit_registry);
 153
 154         sd_bus_flush_close_unref(m->bus);
 155         sd_event_unref(m->event);
 156
 157         safe_close(m->reserve_vt_fd);
 158
 159         strv_free(m->kill_only_users);
 160         strv_free(m->kill_exclude_users);
 161
 162         free(m->scheduled_shutdown_type);
 163         free(m->scheduled_shutdown_tty);
 164         free(m->wall_message);
 165         free(m->action_job);
 166
 167         return mfree(m);
 168 }
 169
 170 static int manager_enumerate_devices(Manager *m) {
 171         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
 172         sd_device *d;
 173         int r;
 174
 175         assert(m);
 176
 177         /* Loads devices from udev and creates seats for them as
 178          * necessary */
 179
 180         r = sd_device_enumerator_new(&e);
 181         if (r < 0)
 182                 return r;
 183
 184         r = sd_device_enumerator_add_match_tag(e, "master-of-seat");
 185         if (r < 0)
 186                 return r;
 187
 188         FOREACH_DEVICE(e, d) {
 189                 int k;
 190
 191                 k = manager_process_seat_device(m, d);
 192                 if (k < 0)
 193                         r = k;
 194         }
 195
 196         return r;
 197 }
 198
 199 static int manager_enumerate_buttons(Manager *m) {
 200         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
 201         sd_device *d;
 202         int r;
 203
 204         assert(m);
 205
 206         /* Loads buttons from udev */
 207
 208         if (manager_all_buttons_ignored(m))
 209                 return 0;
 210
 211         r = sd_device_enumerator_new(&e);
 212         if (r < 0)
 213                 return r;
 214
 215         r = sd_device_enumerator_add_match_subsystem(e, "input", true);
 216         if (r < 0)
 217                 return r;
 218
 219         r = sd_device_enumerator_add_match_tag(e, "power-switch");
 220         if (r < 0)
 221                 return r;
 222
 223         FOREACH_DEVICE(e, d) {
 224                 int k;
 225
 226                 k = manager_process_button_device(m, d);
 227                 if (k < 0)
 228                         r = k;
 229         }
 230
 231         return r;
 232 }
 233
 234 static int manager_enumerate_seats(Manager *m) {
 235         _cleanup_closedir_ DIR *d = NULL;
 236         struct dirent *de;
 237         int r = 0;
 238
 239         assert(m);
 240
 241         /* This loads data about seats stored on disk, but does not
 242          * actually create any seats. Removes data of seats that no
 243          * longer exist. */
 244
 245         d = opendir("/run/systemd/seats");
 246         if (!d) {
 247                 if (errno == ENOENT)
 248                         return 0;
 249
 250                 return log_error_errno(errno, "Failed to open /run/systemd/seats: %m");
 251         }
 252
 253         FOREACH_DIRENT(de, d, return -errno) {
 254                 Seat *s;
 255                 int k;
 256
 257                 if (!dirent_is_file(de))
 258                         continue;
 259
 260                 s = hashmap_get(m->seats, de->d_name);
 261                 if (!s) {
 262                         if (unlinkat(dirfd(d), de->d_name, 0) < 0)
 263                                 log_warning("Failed to remove /run/systemd/seats/%s: %m",
 264                                             de->d_name);
 265                         continue;
 266                 }
 267
 268                 k = seat_load(s);
 269                 if (k < 0)
 270                         r = k;
 271         }
 272
 273         return r;
 274 }
 275
 276 static int manager_enumerate_linger_users(Manager *m) {
 277         _cleanup_closedir_ DIR *d = NULL;
 278         struct dirent *de;
 279         int r = 0;
 280
 281         assert(m);
 282
 283         d = opendir("/var/lib/systemd/linger");
 284         if (!d) {
 285                 if (errno == ENOENT)
 286                         return 0;
 287
 288                 return log_error_errno(errno, "Failed to open /var/lib/systemd/linger/: %m");
 289         }
 290
 291         FOREACH_DIRENT(de, d, return -errno) {
 292                 int k;
 293
 294                 if (!dirent_is_file(de))
 295                         continue;
 296
 297                 k = manager_add_user_by_name(m, de->d_name, NULL);
 298                 if (k < 0) {
 299                         log_notice_errno(k, "Couldn't add lingering user %s: %m", de->d_name);
 300                         r = k;
 301                 }
 302         }
 303
 304         return r;
 305 }
 306
 307 static int manager_enumerate_users(Manager *m) {
 308         _cleanup_closedir_ DIR *d = NULL;
 309         struct dirent *de;
 310         int r, k;
 311
 312         assert(m);
 313
 314         /* Add lingering users */
 315         r = manager_enumerate_linger_users(m);
 316
 317         /* Read in user data stored on disk */
 318         d = opendir("/run/systemd/users");
 319         if (!d) {
 320                 if (errno == ENOENT)
 321                         return 0;
 322
 323                 return log_error_errno(errno, "Failed to open /run/systemd/users: %m");
 324         }
 325
 326         FOREACH_DIRENT(de, d, return -errno) {
 327                 User *u;
 328
 329                 if (!dirent_is_file(de))
 330                         continue;
 331
 332                 k = manager_add_user_by_name(m, de->d_name, &u);
 333                 if (k < 0) {
 334                         log_error_errno(k, "Failed to add user by file name %s: %m", de->d_name);
 335
 336                         r = k;
 337                         continue;
 338                 }
 339
 340                 user_add_to_gc_queue(u);
 341
 342                 k = user_load(u);
 343                 if (k < 0)
 344                         r = k;
 345         }
 346
 347         return r;
 348 }
 349
 350 static int parse_fdname(const char *fdname, char **session_id, dev_t *dev) {
 351         _cleanup_strv_free_ char **parts = NULL;
 352         _cleanup_free_ char *id = NULL;
 353         unsigned major, minor;
 354         int r;
 355
 356         parts = strv_split(fdname, "-");
 357         if (!parts)
 358                 return -ENOMEM;
 359         if (strv_length(parts) != 5)
 360                 return -EINVAL;
 361
 362         if (!streq(parts[0], "session"))
 363                 return -EINVAL;
 364
 365         id = strdup(parts[1]);
 366         if (!id)
 367                 return -ENOMEM;
 368
 369         if (!streq(parts[2], "device"))
 370                 return -EINVAL;
 371
 372         r = safe_atou(parts[3], &major);
 373         if (r < 0)
 374                 return r;
 375         r = safe_atou(parts[4], &minor);
 376         if (r < 0)
 377                 return r;
 378
 379         *dev = makedev(major, minor);
 380         *session_id = TAKE_PTR(id);
 381
 382         return 0;
 383 }
 384
 385 static int deliver_fd(Manager *m, const char *fdname, int fd) {
 386         _cleanup_free_ char *id = NULL;
 387         SessionDevice *sd;
 388         struct stat st;
 389         Session *s;
 390         dev_t dev;
 391         int r;
 392
 393         assert(m);
 394         assert(fd >= 0);
 395
 396         r = parse_fdname(fdname, &id, &dev);
 397         if (r < 0)
 398                 return log_debug_errno(r, "Failed to parse fd name %s: %m", fdname);
 399
 400         s = hashmap_get(m->sessions, id);
 401         if (!s)
 402                 /* If the session doesn't exist anymore, the associated session device attached to this fd
 403                  * doesn't either. Let's simply close this fd. */
 404                 return log_debug_errno(SYNTHETIC_ERRNO(ENXIO), "Failed to attach fd for unknown session: %s", id);
 405
 406         if (fstat(fd, &st) < 0)
 407                 /* The device is allowed to go away at a random point, in which case fstat() failing is
 408                  * expected. */
 409                 return log_debug_errno(errno, "Failed to stat device fd for session %s: %m", id);
 410
 411         if (!S_ISCHR(st.st_mode) || st.st_rdev != dev)
 412                 return log_debug_errno(SYNTHETIC_ERRNO(ENODEV), "Device fd doesn't point to the expected character device node");
 413
 414         sd = hashmap_get(s->devices, &dev);
 415         if (!sd)
 416                 /* Weird, we got an fd for a session device which wasn't recorded in the session state
 417                  * file... */
 418                 return log_warning_errno(SYNTHETIC_ERRNO(ENODEV), "Got fd for missing session device [%u:%u] in session %s",
 419                                          major(dev), minor(dev), s->id);
 420
 421         log_debug("Attaching fd to session device [%u:%u] for session %s",
 422                   major(dev), minor(dev), s->id);
 423
 424         session_device_attach_fd(sd, fd, s->was_active);
 425         return 0;
 426 }
 427
 428 static int manager_attach_fds(Manager *m) {
 429         _cleanup_strv_free_ char **fdnames = NULL;
 430         int n;
 431
 432         /* Upon restart, PID1 will send us back all fds of session devices that we previously opened. Each
 433          * file descriptor is associated with a given session. The session ids are passed through FDNAMES. */
 434
 435         n = sd_listen_fds_with_names(true, &fdnames);
 436         if (n < 0)
 437                 return log_warning_errno(n, "Failed to acquire passed fd list: %m");
 438         if (n == 0)
 439                 return 0;
 440
 441         for (int i = 0; i < n; i++) {
 442                 int fd = SD_LISTEN_FDS_START + i;
 443
 444                 if (deliver_fd(m, fdnames[i], fd) >= 0)
 445                         continue;
 446
 447                 /* Hmm, we couldn't deliver the fd to any session device object? If so, let's close the fd */
 448                 safe_close(fd);
 449
 450                 /* Remove from fdstore as well */
 451                 (void) sd_notifyf(false,
 452                                   "FDSTOREREMOVE=1\n"
 453                                   "FDNAME=%s", fdnames[i]);
 454         }
 455
 456         return 0;
 457 }
 458
 459 static int manager_enumerate_sessions(Manager *m) {
 460         _cleanup_closedir_ DIR *d = NULL;
 461         struct dirent *de;
 462         int r = 0, k;
 463
 464         assert(m);
 465
 466         /* Read in session data stored on disk */
 467         d = opendir("/run/systemd/sessions");
 468         if (!d) {
 469                 if (errno == ENOENT)
 470                         return 0;
 471
 472                 return log_error_errno(errno, "Failed to open /run/systemd/sessions: %m");
 473         }
 474
 475         FOREACH_DIRENT(de, d, return -errno) {
 476                 struct Session *s;
 477
 478                 if (!dirent_is_file(de))
 479                         continue;
 480
 481                 if (!session_id_valid(de->d_name)) {
 482                         log_warning("Invalid session file name '%s', ignoring.", de->d_name);
 483                         r = -EINVAL;
 484                         continue;
 485                 }
 486
 487                 k = manager_add_session(m, de->d_name, &s);
 488                 if (k < 0) {
 489                         log_error_errno(k, "Failed to add session by file name %s: %m", de->d_name);
 490                         r = k;
 491                         continue;
 492                 }
 493
 494                 session_add_to_gc_queue(s);
 495
 496                 k = session_load(s);
 497                 if (k < 0)
 498                         r = k;
 499         }
 500
 501         /* We might be restarted and PID1 could have sent us back the session device fds we previously
 502          * saved. */
 503         (void) manager_attach_fds(m);
 504
 505         return r;
 506 }
 507
 508 static int manager_enumerate_inhibitors(Manager *m) {
 509         _cleanup_closedir_ DIR *d = NULL;
 510         struct dirent *de;
 511         int r = 0;
 512
 513         assert(m);
 514
 515         d = opendir("/run/systemd/inhibit");
 516         if (!d) {
 517                 if (errno == ENOENT)
 518                         return 0;
 519
 520                 return log_error_errno(errno, "Failed to open /run/systemd/inhibit: %m");
 521         }
 522
 523         FOREACH_DIRENT(de, d, return -errno) {
 524                 int k;
 525                 Inhibitor *i;
 526
 527                 if (!dirent_is_file(de))
 528                         continue;
 529
 530                 k = manager_add_inhibitor(m, de->d_name, &i);
 531                 if (k < 0) {
 532                         log_notice_errno(k, "Couldn't add inhibitor %s: %m", de->d_name);
 533                         r = k;
 534                         continue;
 535                 }
 536
 537                 k = inhibitor_load(i);
 538                 if (k < 0)
 539                         r = k;
 540         }
 541
 542         return r;
 543 }
 544
 545 static int manager_dispatch_seat_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
 546         Manager *m = userdata;
 547
 548         assert(m);
 549         assert(device);
 550
 551         manager_process_seat_device(m, device);
 552         return 0;
 553 }
 554
 555 static int manager_dispatch_device_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
 556         Manager *m = userdata;
 557
 558         assert(m);
 559         assert(device);
 560
 561         manager_process_seat_device(m, device);
 562         return 0;
 563 }
 564
 565 static int manager_dispatch_vcsa_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
 566         Manager *m = userdata;
 567         const char *name;
 568
 569         assert(m);
 570         assert(device);
 571
 572         /* Whenever a VCSA device is removed try to reallocate our
 573          * VTs, to make sure our auto VTs never go away. */
 574
 575         if (sd_device_get_sysname(device, &name) >= 0 &&
 576             startswith(name, "vcsa") &&
 577             device_for_action(device, DEVICE_ACTION_REMOVE))
 578                 seat_preallocate_vts(m->seat0);
 579
 580         return 0;
 581 }
 582
 583 static int manager_dispatch_button_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
 584         Manager *m = userdata;
 585
 586         assert(m);
 587         assert(device);
 588
 589         manager_process_button_device(m, device);
 590         return 0;
 591 }
 592
 593 static int manager_dispatch_console(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
 594         Manager *m = userdata;
 595
 596         assert(m);
 597         assert(m->seat0);
 598         assert(m->console_active_fd == fd);
 599
 600         seat_read_active_vt(m->seat0);
 601         return 0;
 602 }
 603
 604 static int manager_reserve_vt(Manager *m) {
 605         _cleanup_free_ char *p = NULL;
 606
 607         assert(m);
 608
 609         if (m->reserve_vt <= 0)
 610                 return 0;
 611
 612         if (asprintf(&p, "/dev/tty%u", m->reserve_vt) < 0)
 613                 return log_oom();
 614
 615         m->reserve_vt_fd = open(p, O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK);
 616         if (m->reserve_vt_fd < 0) {
 617
 618                 /* Don't complain on VT-less systems */
 619                 if (errno != ENOENT)
 620                         log_warning_errno(errno, "Failed to pin reserved VT: %m");
 621                 return -errno;
 622         }
 623
 624         return 0;
 625 }
 626
 627 static int manager_connect_bus(Manager *m) {
 628         int r;
 629
 630         assert(m);
 631         assert(!m->bus);
 632
 633         r = sd_bus_default_system(&m->bus);
 634         if (r < 0)
 635                 return log_error_errno(r, "Failed to connect to system bus: %m");
 636
 637         r = sd_bus_add_object_vtable(m->bus, NULL, "/org/freedesktop/login1", "org.freedesktop.login1.Manager", manager_vtable, m);
 638         if (r < 0)
 639                 return log_error_errno(r, "Failed to add manager object vtable: %m");
 640
 641         r = sd_bus_add_fallback_vtable(m->bus, NULL, "/org/freedesktop/login1/seat", "org.freedesktop.login1.Seat", seat_vtable, seat_object_find, m);
 642         if (r < 0)
 643                 return log_error_errno(r, "Failed to add seat object vtable: %m");
 644
 645         r = sd_bus_add_node_enumerator(m->bus, NULL, "/org/freedesktop/login1/seat", seat_node_enumerator, m);
 646         if (r < 0)
 647                 return log_error_errno(r, "Failed to add seat enumerator: %m");
 648
 649         r = sd_bus_add_fallback_vtable(m->bus, NULL, "/org/freedesktop/login1/session", "org.freedesktop.login1.Session", session_vtable, session_object_find, m);
 650         if (r < 0)
 651                 return log_error_errno(r, "Failed to add session object vtable: %m");
 652
 653         r = sd_bus_add_node_enumerator(m->bus, NULL, "/org/freedesktop/login1/session", session_node_enumerator, m);
 654         if (r < 0)
 655                 return log_error_errno(r, "Failed to add session enumerator: %m");
 656
 657         r = sd_bus_add_fallback_vtable(m->bus, NULL, "/org/freedesktop/login1/user", "org.freedesktop.login1.User", user_vtable, user_object_find, m);
 658         if (r < 0)
 659                 return log_error_errno(r, "Failed to add user object vtable: %m");
 660
 661         r = sd_bus_add_node_enumerator(m->bus, NULL, "/org/freedesktop/login1/user", user_node_enumerator, m);
 662         if (r < 0)
 663                 return log_error_errno(r, "Failed to add user enumerator: %m");
 664
 665         r = sd_bus_match_signal_async(
 666                         m->bus,
 667                         NULL,
 668                         "org.freedesktop.systemd1",
 669                         "/org/freedesktop/systemd1",
 670                         "org.freedesktop.systemd1.Manager",
 671                         "JobRemoved",
 672                         match_job_removed, NULL, m);
 673         if (r < 0)
 674                 return log_error_errno(r, "Failed to request match for JobRemoved: %m");
 675
 676         r = sd_bus_match_signal_async(
 677                         m->bus,
 678                         NULL,
 679                         "org.freedesktop.systemd1",
 680                         "/org/freedesktop/systemd1",
 681                         "org.freedesktop.systemd1.Manager",
 682                         "UnitRemoved",
 683                         match_unit_removed, NULL, m);
 684         if (r < 0)
 685                 return log_error_errno(r, "Failed to request match for UnitRemoved: %m");
 686
 687         r = sd_bus_match_signal_async(
 688                         m->bus,
 689                         NULL,
 690                         "org.freedesktop.systemd1",
 691                         NULL,
 692                         "org.freedesktop.DBus.Properties",
 693                         "PropertiesChanged",
 694                         match_properties_changed, NULL, m);
 695         if (r < 0)
 696                 return log_error_errno(r, "Failed to request match for PropertiesChanged: %m");
 697
 698         r = sd_bus_match_signal_async(
 699                         m->bus,
 700                         NULL,
 701                         "org.freedesktop.systemd1",
 702                         "/org/freedesktop/systemd1",
 703                         "org.freedesktop.systemd1.Manager",
 704                         "Reloading",
 705                         match_reloading, NULL, m);
 706         if (r < 0)
 707                 return log_error_errno(r, "Failed to request match for Reloading: %m");
 708
 709         r = sd_bus_call_method_async(
 710                         m->bus,
 711                         NULL,
 712                         "org.freedesktop.systemd1",
 713                         "/org/freedesktop/systemd1",
 714                         "org.freedesktop.systemd1.Manager",
 715                         "Subscribe",
 716                         NULL, NULL,
 717                         NULL);
 718         if (r < 0)
 719                 return log_error_errno(r, "Failed to enable subscription: %m");
 720
 721         r = sd_bus_request_name_async(m->bus, NULL, "org.freedesktop.login1", 0, NULL, NULL);
 722         if (r < 0)
 723                 return log_error_errno(r, "Failed to request name: %m");
 724
 725         r = sd_bus_attach_event(m->bus, m->event, SD_EVENT_PRIORITY_NORMAL);
 726         if (r < 0)
 727                 return log_error_errno(r, "Failed to attach bus to event loop: %m");
 728
 729         return 0;
 730 }
 731
 732 static int manager_vt_switch(sd_event_source *src, const struct signalfd_siginfo *si, void *data) {
 733         Manager *m = data;
 734         Session *active, *iter;
 735
 736         /*
 737          * We got a VT-switch signal and we have to acknowledge it immediately.
 738          * Preferably, we'd just use m->seat0->active->vtfd, but unfortunately,
 739          * old user-space might run multiple sessions on a single VT, *sigh*.
 740          * Therefore, we have to iterate all sessions and find one with a vtfd
 741          * on the requested VT.
 742          * As only VTs with active controllers have VT_PROCESS set, our current
 743          * notion of the active VT might be wrong (for instance if the switch
 744          * happens while we setup VT_PROCESS). Therefore, read the current VT
 745          * first and then use s->active->vtnr as reference. Note that this is
 746          * not racy, as no further VT-switch can happen as long as we're in
 747          * synchronous VT_PROCESS mode.
 748          */
 749
 750         assert(m->seat0);
 751         seat_read_active_vt(m->seat0);
 752
 753         active = m->seat0->active;
 754         if (!active || active->vtnr < 1) {
 755                 _cleanup_close_ int fd = -1;
 756                 int r;
 757
 758                 /* We are requested to acknowledge the VT-switch signal by the kernel but
 759                  * there's no registered sessions for the current VT. Normally this
 760                  * shouldn't happen but something wrong might have happened when we tried
 761                  * to release the VT. Better be safe than sorry, and try to release the VT
 762                  * one more time otherwise the user will be locked with the current VT. */
 763
 764                 log_warning("Received VT_PROCESS signal without a registered session, restoring VT.");
 765
 766                 /* At this point we only have the kernel mapping for referring to the
 767                  * current VT. */
 768                 fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK);
 769                 if (fd < 0) {
 770                         log_warning_errno(fd, "Failed to open, ignoring: %m");
 771                         return 0;
 772                 }
 773
 774                 r = vt_release(fd, true);
 775                 if (r < 0)
 776                         log_warning_errno(r, "Failed to release VT, ignoring: %m");
 777
 778                 return 0;
 779         }
 780
 781         if (active->vtfd >= 0) {
 782                 session_leave_vt(active);
 783         } else {
 784                 LIST_FOREACH(sessions_by_seat, iter, m->seat0->sessions) {
 785                         if (iter->vtnr == active->vtnr && iter->vtfd >= 0) {
 786                                 session_leave_vt(iter);
 787                                 break;
 788                         }
 789                 }
 790         }
 791
 792         return 0;
 793 }
 794
 795 static int manager_connect_console(Manager *m) {
 796         int r;
 797
 798         assert(m);
 799         assert(m->console_active_fd < 0);
 800
 801         /* On certain systems (such as S390, Xen, and containers) /dev/tty0 does not exist (as there is no VC), so
 802          * don't fail if we can't open it. */
 803
 804         if (access("/dev/tty0", F_OK) < 0)
 805                 return 0;
 806
 807         m->console_active_fd = open("/sys/class/tty/tty0/active", O_RDONLY|O_NOCTTY|O_CLOEXEC);
 808         if (m->console_active_fd < 0) {
 809
 810                 /* On some systems /dev/tty0 may exist even though /sys/class/tty/tty0 does not. These are broken, but
 811                  * common. Let's complain but continue anyway. */
 812                 if (errno == ENOENT) {
 813                         log_warning_errno(errno, "System has /dev/tty0 but not /sys/class/tty/tty0/active which is broken, ignoring: %m");
 814                         return 0;
 815                 }
 816
 817                 return log_error_errno(errno, "Failed to open /sys/class/tty/tty0/active: %m");
 818         }
 819
 820         r = sd_event_add_io(m->event, &m->console_active_event_source, m->console_active_fd, 0, manager_dispatch_console, m);
 821         if (r < 0)
 822                 return log_error_errno(r, "Failed to watch foreground console: %m");
 823
 824         /*
 825          * SIGRTMIN is used as global VT-release signal, SIGRTMIN + 1 is used
 826          * as VT-acquire signal. We ignore any acquire-events (yes, we still
 827          * have to provide a valid signal-number for it!) and acknowledge all
 828          * release events immediately.
 829          */
 830
 831         if (SIGRTMIN + 1 > SIGRTMAX)
 832                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 833                                        "Not enough real-time signals available: %u-%u",
 834                                        SIGRTMIN, SIGRTMAX);
 835
 836         assert_se(ignore_signals(SIGRTMIN + 1, -1) >= 0);
 837         assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGRTMIN, -1) >= 0);
 838
 839         r = sd_event_add_signal(m->event, NULL, SIGRTMIN, manager_vt_switch, m);
 840         if (r < 0)
 841                 return log_error_errno(r, "Failed to subscribe to signal: %m");
 842
 843         return 0;
 844 }
 845
 846 static int manager_connect_udev(Manager *m) {
 847         int r;
 848
 849         assert(m);
 850         assert(!m->device_seat_monitor);
 851         assert(!m->device_monitor);
 852         assert(!m->device_vcsa_monitor);
 853         assert(!m->device_button_monitor);
 854
 855         r = sd_device_monitor_new(&m->device_seat_monitor);
 856         if (r < 0)
 857                 return r;
 858
 859         r = sd_device_monitor_filter_add_match_tag(m->device_seat_monitor, "master-of-seat");
 860         if (r < 0)
 861                 return r;
 862
 863         r = sd_device_monitor_attach_event(m->device_seat_monitor, m->event);
 864         if (r < 0)
 865                 return r;
 866
 867         r = sd_device_monitor_start(m->device_seat_monitor, manager_dispatch_seat_udev, m);
 868         if (r < 0)
 869                 return r;
 870
 871         (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_seat_monitor), "logind-seat-monitor");
 872
 873         r = sd_device_monitor_new(&m->device_monitor);
 874         if (r < 0)
 875                 return r;
 876
 877         r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_monitor, "input", NULL);
 878         if (r < 0)
 879                 return r;
 880
 881         r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_monitor, "graphics", NULL);
 882         if (r < 0)
 883                 return r;
 884
 885         r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_monitor, "drm", NULL);
 886         if (r < 0)
 887                 return r;
 888
 889         r = sd_device_monitor_attach_event(m->device_monitor, m->event);
 890         if (r < 0)
 891                 return r;
 892
 893         r = sd_device_monitor_start(m->device_monitor, manager_dispatch_device_udev, m);
 894         if (r < 0)
 895                 return r;
 896
 897         (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_monitor), "logind-device-monitor");
 898
 899         /* Don't watch keys if nobody cares */
 900         if (!manager_all_buttons_ignored(m)) {
 901                 r = sd_device_monitor_new(&m->device_button_monitor);
 902                 if (r < 0)
 903                         return r;
 904
 905                 r = sd_device_monitor_filter_add_match_tag(m->device_button_monitor, "power-switch");
 906                 if (r < 0)
 907                         return r;
 908
 909                 r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_button_monitor, "input", NULL);
 910                 if (r < 0)
 911                         return r;
 912
 913                 r = sd_device_monitor_attach_event(m->device_button_monitor, m->event);
 914                 if (r < 0)
 915                         return r;
 916
 917                 r = sd_device_monitor_start(m->device_button_monitor, manager_dispatch_button_udev, m);
 918                 if (r < 0)
 919                         return r;
 920
 921                 (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_button_monitor), "logind-button-monitor");
 922         }
 923
 924         /* Don't bother watching VCSA devices, if nobody cares */
 925         if (m->n_autovts > 0 && m->console_active_fd >= 0) {
 926
 927                 r = sd_device_monitor_new(&m->device_vcsa_monitor);
 928                 if (r < 0)
 929                         return r;
 930
 931                 r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_vcsa_monitor, "vc", NULL);
 932                 if (r < 0)
 933                         return r;
 934
 935                 r = sd_device_monitor_attach_event(m->device_vcsa_monitor, m->event);
 936                 if (r < 0)
 937                         return r;
 938
 939                 r = sd_device_monitor_start(m->device_vcsa_monitor, manager_dispatch_vcsa_udev, m);
 940                 if (r < 0)
 941                         return r;
 942
 943                 (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_vcsa_monitor), "logind-vcsa-monitor");
 944         }
 945
 946         return 0;
 947 }
 948
 949 static void manager_gc(Manager *m, bool drop_not_started) {
 950         Seat *seat;
 951         Session *session;
 952         User *user;
 953
 954         assert(m);
 955
 956         while ((seat = m->seat_gc_queue)) {
 957                 LIST_REMOVE(gc_queue, m->seat_gc_queue, seat);
 958                 seat->in_gc_queue = false;
 959
 960                 if (seat_may_gc(seat, drop_not_started)) {
 961                         seat_stop(seat, false);
 962                         seat_free(seat);
 963                 }
 964         }
 965
 966         while ((session = m->session_gc_queue)) {
 967                 LIST_REMOVE(gc_queue, m->session_gc_queue, session);
 968                 session->in_gc_queue = false;
 969
 970                 /* First, if we are not closing yet, initiate stopping */
 971                 if (session_may_gc(session, drop_not_started) &&
 972                     session_get_state(session) != SESSION_CLOSING)
 973                         (void) session_stop(session, false);
 974
 975                 /* Normally, this should make the session referenced
 976                  * again, if it doesn't then let's get rid of it
 977                  * immediately */
 978                 if (session_may_gc(session, drop_not_started)) {
 979                         (void) session_finalize(session);
 980                         session_free(session);
 981                 }
 982         }
 983
 984         while ((user = m->user_gc_queue)) {
 985                 LIST_REMOVE(gc_queue, m->user_gc_queue, user);
 986                 user->in_gc_queue = false;
 987
 988                 /* First step: queue stop jobs */
 989                 if (user_may_gc(user, drop_not_started))
 990                         (void) user_stop(user, false);
 991
 992                 /* Second step: finalize user */
 993                 if (user_may_gc(user, drop_not_started)) {
 994                         (void) user_finalize(user);
 995                         user_free(user);
 996                 }
 997         }
 998 }
 999
1000 static int manager_dispatch_idle_action(sd_event_source *s, uint64_t t, void *userdata) {
1001         Manager *m = userdata;
1002         struct dual_timestamp since;
1003         usec_t n, elapse;
1004         int r;
1005
1006         assert(m);
1007
1008         if (m->idle_action == HANDLE_IGNORE ||
1009             m->idle_action_usec <= 0)
1010                 return 0;
1011
1012         n = now(CLOCK_MONOTONIC);
1013
1014         r = manager_get_idle_hint(m, &since);
1015         if (r <= 0)
1016                 /* Not idle. Let's check if after a timeout it might be idle then. */
1017                 elapse = n + m->idle_action_usec;
1018         else {
1019                 /* Idle! Let's see if it's time to do something, or if
1020                  * we shall sleep for longer. */
1021
1022                 if (n >= since.monotonic + m->idle_action_usec &&
1023                     (m->idle_action_not_before_usec <= 0 || n >= m->idle_action_not_before_usec + m->idle_action_usec)) {
1024                         log_info("System idle. Taking action.");
1025
1026                         manager_handle_action(m, 0, m->idle_action, false, false);
1027                         m->idle_action_not_before_usec = n;
1028                 }
1029
1030                 elapse = MAX(since.monotonic, m->idle_action_not_before_usec) + m->idle_action_usec;
1031         }
1032
1033         if (!m->idle_action_event_source) {
1034
1035                 r = sd_event_add_time(
1036                                 m->event,
1037                                 &m->idle_action_event_source,
1038                                 CLOCK_MONOTONIC,
1039                                 elapse, USEC_PER_SEC*30,
1040                                 manager_dispatch_idle_action, m);
1041                 if (r < 0)
1042                         return log_error_errno(r, "Failed to add idle event source: %m");
1043
1044                 r = sd_event_source_set_priority(m->idle_action_event_source, SD_EVENT_PRIORITY_IDLE+10);
1045                 if (r < 0)
1046                         return log_error_errno(r, "Failed to set idle event source priority: %m");
1047         } else {
1048                 r = sd_event_source_set_time(m->idle_action_event_source, elapse);
1049                 if (r < 0)
1050                         return log_error_errno(r, "Failed to set idle event timer: %m");
1051
1052                 r = sd_event_source_set_enabled(m->idle_action_event_source, SD_EVENT_ONESHOT);
1053                 if (r < 0)
1054                         return log_error_errno(r, "Failed to enable idle event timer: %m");
1055         }
1056
1057         return 0;
1058 }
1059
1060 static int manager_dispatch_reload_signal(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
1061         Manager *m = userdata;
1062         int r;
1063
1064         manager_reset_config(m);
1065         r = manager_parse_config_file(m);
1066         if (r < 0)
1067                 log_warning_errno(r, "Failed to parse config file, using defaults: %m");
1068         else
1069                 log_info("Config file reloaded.");
1070
1071         return 0;
1072 }
1073
1074 static int manager_startup(Manager *m) {
1075         int r;
1076         Seat *seat;
1077         Session *session;
1078         User *user;
1079         Button *button;
1080         Inhibitor *inhibitor;
1081         Iterator i;
1082
1083         assert(m);
1084
1085         r = sd_event_add_signal(m->event, NULL, SIGHUP, manager_dispatch_reload_signal, m);
1086         if (r < 0)
1087                 return log_error_errno(r, "Failed to register SIGHUP handler: %m");
1088
1089         /* Connect to utmp */
1090         manager_connect_utmp(m);
1091
1092         /* Connect to console */
1093         r = manager_connect_console(m);
1094         if (r < 0)
1095                 return r;
1096
1097         /* Connect to udev */
1098         r = manager_connect_udev(m);
1099         if (r < 0)
1100                 return log_error_errno(r, "Failed to create udev watchers: %m");
1101
1102         /* Connect to the bus */
1103         r = manager_connect_bus(m);
1104         if (r < 0)
1105                 return r;
1106
1107         /* Instantiate magic seat 0 */
1108         r = manager_add_seat(m, "seat0", &m->seat0);
1109         if (r < 0)
1110                 return log_error_errno(r, "Failed to add seat0: %m");
1111
1112         r = manager_set_lid_switch_ignore(m, 0 + m->holdoff_timeout_usec);
1113         if (r < 0)
1114                 log_warning_errno(r, "Failed to set up lid switch ignore event source: %m");
1115
1116         /* Deserialize state */
1117         r = manager_enumerate_devices(m);
1118         if (r < 0)
1119                 log_warning_errno(r, "Device enumeration failed: %m");
1120
1121         r = manager_enumerate_seats(m);
1122         if (r < 0)
1123                 log_warning_errno(r, "Seat enumeration failed: %m");
1124
1125         r = manager_enumerate_users(m);
1126         if (r < 0)
1127                 log_warning_errno(r, "User enumeration failed: %m");
1128
1129         r = manager_enumerate_sessions(m);
1130         if (r < 0)
1131                 log_warning_errno(r, "Session enumeration failed: %m");
1132
1133         r = manager_enumerate_inhibitors(m);
1134         if (r < 0)
1135                 log_warning_errno(r, "Inhibitor enumeration failed: %m");
1136
1137         r = manager_enumerate_buttons(m);
1138         if (r < 0)
1139                 log_warning_errno(r, "Button enumeration failed: %m");
1140
1141         /* Remove stale objects before we start them */
1142         manager_gc(m, false);
1143
1144         /* Reserve the special reserved VT */
1145         manager_reserve_vt(m);
1146
1147         /* Read in utmp if it exists */
1148         manager_read_utmp(m);
1149
1150         /* And start everything */
1151         HASHMAP_FOREACH(seat, m->seats, i)
1152                 (void) seat_start(seat);
1153
1154         HASHMAP_FOREACH(user, m->users, i)
1155                 (void) user_start(user);
1156
1157         HASHMAP_FOREACH(session, m->sessions, i)
1158                 (void) session_start(session, NULL, NULL);
1159
1160         HASHMAP_FOREACH(inhibitor, m->inhibitors, i)
1161                 inhibitor_start(inhibitor);
1162
1163         HASHMAP_FOREACH(button, m->buttons, i)
1164                 button_check_switches(button);
1165
1166         manager_dispatch_idle_action(NULL, 0, m);
1167
1168         return 0;
1169 }
1170
1171 static int manager_run(Manager *m) {
1172         int r;
1173
1174         assert(m);
1175
1176         for (;;) {
1177                 r = sd_event_get_state(m->event);
1178                 if (r < 0)
1179                         return r;
1180                 if (r == SD_EVENT_FINISHED)
1181                         return 0;
1182
1183                 manager_gc(m, true);
1184
1185                 r = manager_dispatch_delayed(m, false);
1186                 if (r < 0)
1187                         return r;
1188                 if (r > 0)
1189                         continue;
1190
1191                 r = sd_event_run(m->event, (uint64_t) -1);
1192                 if (r < 0)
1193                         return r;
1194         }
1195 }
1196
1197 static int run(int argc, char *argv[]) {
1198         _cleanup_(manager_unrefp) Manager *m = NULL;
1199         int r;
1200
1201         log_set_facility(LOG_AUTH);
1202         log_setup_service();
1203
1204         umask(0022);
1205
1206         if (argc != 1) {
1207                 log_error("This program takes no arguments.");
1208                 return -EINVAL;
1209         }
1210
1211         r = mac_selinux_init();
1212         if (r < 0)
1213                 return log_error_errno(r, "Could not initialize labelling: %m");
1214
1215         /* Always create the directories people can create inotify watches in. Note that some applications might check
1216          * for the existence of /run/systemd/seats/ to determine whether logind is available, so please always make
1217          * sure these directories are created early on and unconditionally. */
1218         (void) mkdir_label("/run/systemd/seats", 0755);
1219         (void) mkdir_label("/run/systemd/users", 0755);
1220         (void) mkdir_label("/run/systemd/sessions", 0755);
1221
1222         assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGHUP, SIGTERM, SIGINT, SIGCHLD, -1) >= 0);
1223
1224         r = manager_new(&m);
1225         if (r < 0)
1226                 return log_error_errno(r, "Failed to allocate manager object: %m");
1227
1228         (void) manager_parse_config_file(m);
1229
1230         r = manager_startup(m);
1231         if (r < 0)
1232                 return log_error_errno(r, "Failed to fully start up daemon: %m");
1233
1234         log_debug("systemd-logind running as pid "PID_FMT, getpid_cached());
1235         (void) sd_notify(false,
1236                          "READY=1\n"
1237                          "STATUS=Processing requests...");
1238
1239         r = manager_run(m);
1240
1241         log_debug("systemd-logind stopped as pid "PID_FMT, getpid_cached());
1242         (void) sd_notify(false,
1243                          "STOPPING=1\n"
1244                          "STATUS=Shutting down...");
1245
1246         return r;
1247 }
1248
1249 DEFINE_MAIN_FUNCTION(run);