src/login/logind.c

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