src/login/logind.c

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