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