src/login/logind.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <errno.h>
   4 #include <fcntl.h>
   5 #include <string.h>
   6 #include <unistd.h>
   7
   8 #include "sd-daemon.h"
   9 #include "sd-device.h"
  10
  11 #include "alloc-util.h"
  12 #include "bus-error.h"
  13 #include "bus-util.h"
  14 #include "cgroup-util.h"
  15 #include "def.h"
  16 #include "device-util.h"
  17 #include "dirent-util.h"
  18 #include "fd-util.h"
  19 #include "format-util.h"
  20 #include "fs-util.h"
  21 #include "logind.h"
  22 #include "main-func.h"
  23 #include "parse-util.h"
  24 #include "process-util.h"
  25 #include "selinux-util.h"
  26 #include "signal-util.h"
  27 #include "strv.h"
  28 #include "terminal-util.h"
  29 #include "udev-util.h"
  30
  31 static Manager* manager_unref(Manager *m);
  32 DEFINE_TRIVIAL_CLEANUP_FUNC(Manager*, manager_unref);
  33
  34 static int manager_new(Manager **ret) {
  35         _cleanup_(manager_unrefp) Manager *m = NULL;
  36         int r;
  37
  38         assert(ret);
  39
  40         m = new(Manager, 1);
  41         if (!m)
  42                 return -ENOMEM;
  43
  44         *m = (Manager) {
  45                 .console_active_fd = -1,
  46                 .reserve_vt_fd = -1,
  47         };
  48
  49         m->idle_action_not_before_usec = now(CLOCK_MONOTONIC);
  50
  51         m->devices = hashmap_new(&string_hash_ops);
  52         m->seats = hashmap_new(&string_hash_ops);
  53         m->sessions = hashmap_new(&string_hash_ops);
  54         m->sessions_by_leader = hashmap_new(NULL);
  55         m->users = hashmap_new(NULL);
  56         m->inhibitors = hashmap_new(&string_hash_ops);
  57         m->buttons = hashmap_new(&string_hash_ops);
  58
  59         m->user_units = hashmap_new(&string_hash_ops);
  60         m->session_units = hashmap_new(&string_hash_ops);
  61
  62         if (!m->devices || !m->seats || !m->sessions || !m->sessions_by_leader || !m->users || !m->inhibitors || !m->buttons || !m->user_units || !m->session_units)
  63                 return -ENOMEM;
  64
  65         r = sd_event_default(&m->event);
  66         if (r < 0)
  67                 return r;
  68
  69         r = sd_event_add_signal(m->event, NULL, SIGINT, NULL, NULL);
  70         if (r < 0)
  71                 return r;
  72
  73         r = sd_event_add_signal(m->event, NULL, SIGTERM, NULL, NULL);
  74         if (r < 0)
  75                 return r;
  76
  77         (void) sd_event_set_watchdog(m->event, true);
  78
  79         manager_reset_config(m);
  80
  81         *ret = TAKE_PTR(m);
  82         return 0;
  83 }
  84
  85 static Manager* manager_unref(Manager *m) {
  86         Session *session;
  87         User *u;
  88         Device *d;
  89         Seat *s;
  90         Inhibitor *i;
  91         Button *b;
  92
  93         if (!m)
  94                 return NULL;
  95
  96         while ((session = hashmap_first(m->sessions)))
  97                 session_free(session);
  98
  99         while ((u = hashmap_first(m->users)))
 100                 user_free(u);
 101
 102         while ((d = hashmap_first(m->devices)))
 103                 device_free(d);
 104
 105         while ((s = hashmap_first(m->seats)))
 106                 seat_free(s);
 107
 108         while ((i = hashmap_first(m->inhibitors)))
 109                 inhibitor_free(i);
 110
 111         while ((b = hashmap_first(m->buttons)))
 112                 button_free(b);
 113
 114         hashmap_free(m->devices);
 115         hashmap_free(m->seats);
 116         hashmap_free(m->sessions);
 117         hashmap_free(m->sessions_by_leader);
 118         hashmap_free(m->users);
 119         hashmap_free(m->inhibitors);
 120         hashmap_free(m->buttons);
 121
 122         hashmap_free(m->user_units);
 123         hashmap_free(m->session_units);
 124
 125         sd_event_source_unref(m->idle_action_event_source);
 126         sd_event_source_unref(m->inhibit_timeout_source);
 127         sd_event_source_unref(m->scheduled_shutdown_timeout_source);
 128         sd_event_source_unref(m->nologin_timeout_source);
 129         sd_event_source_unref(m->wall_message_timeout_source);
 130
 131         sd_event_source_unref(m->console_active_event_source);
 132         sd_event_source_unref(m->lid_switch_ignore_event_source);
 133
 134 #if ENABLE_UTMP
 135         sd_event_source_unref(m->utmp_event_source);
 136 #endif
 137
 138         safe_close(m->console_active_fd);
 139
 140         sd_device_monitor_unref(m->device_seat_monitor);
 141         sd_device_monitor_unref(m->device_monitor);
 142         sd_device_monitor_unref(m->device_vcsa_monitor);
 143         sd_device_monitor_unref(m->device_button_monitor);
 144
 145         if (m->unlink_nologin)
 146                 (void) unlink_or_warn("/run/nologin");
 147
 148         bus_verify_polkit_async_registry_free(m->polkit_registry);
 149
 150         sd_bus_flush_close_unref(m->bus);
 151         sd_event_unref(m->event);
 152
 153         safe_close(m->reserve_vt_fd);
 154
 155         strv_free(m->kill_only_users);
 156         strv_free(m->kill_exclude_users);
 157
 158         free(m->scheduled_shutdown_type);
 159         free(m->scheduled_shutdown_tty);
 160         free(m->wall_message);
 161         free(m->action_job);
 162
 163         return mfree(m);
 164 }
 165
 166 static int manager_enumerate_devices(Manager *m) {
 167         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
 168         sd_device *d;
 169         int r;
 170
 171         assert(m);
 172
 173         /* Loads devices from udev and creates seats for them as
 174          * necessary */
 175
 176         r = sd_device_enumerator_new(&e);
 177         if (r < 0)
 178                 return r;
 179
 180         r = sd_device_enumerator_add_match_tag(e, "master-of-seat");
 181         if (r < 0)
 182                 return r;
 183
 184         FOREACH_DEVICE(e, d) {
 185                 int k;
 186
 187                 k = manager_process_seat_device(m, d);
 188                 if (k < 0)
 189                         r = k;
 190         }
 191
 192         return r;
 193 }
 194
 195 static int manager_enumerate_buttons(Manager *m) {
 196         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
 197         sd_device *d;
 198         int r;
 199
 200         assert(m);
 201
 202         /* Loads buttons from udev */
 203
 204         if (manager_all_buttons_ignored(m))
 205                 return 0;
 206
 207         r = sd_device_enumerator_new(&e);
 208         if (r < 0)
 209                 return r;
 210
 211         r = sd_device_enumerator_add_match_subsystem(e, "input", true);
 212         if (r < 0)
 213                 return r;
 214
 215         r = sd_device_enumerator_add_match_tag(e, "power-switch");
 216         if (r < 0)
 217                 return r;
 218
 219         FOREACH_DEVICE(e, d) {
 220                 int k;
 221
 222                 k = manager_process_button_device(m, d);
 223                 if (k < 0)
 224                         r = k;
 225         }
 226
 227         return r;
 228 }
 229
 230 static int manager_enumerate_seats(Manager *m) {
 231         _cleanup_closedir_ DIR *d = NULL;
 232         struct dirent *de;
 233         int r = 0;
 234
 235         assert(m);
 236
 237         /* This loads data about seats stored on disk, but does not
 238          * actually create any seats. Removes data of seats that no
 239          * longer exist. */
 240
 241         d = opendir("/run/systemd/seats");
 242         if (!d) {
 243                 if (errno == ENOENT)
 244                         return 0;
 245
 246                 return log_error_errno(errno, "Failed to open /run/systemd/seats: %m");
 247         }
 248
 249         FOREACH_DIRENT(de, d, return -errno) {
 250                 Seat *s;
 251                 int k;
 252
 253                 if (!dirent_is_file(de))
 254                         continue;
 255
 256                 s = hashmap_get(m->seats, de->d_name);
 257                 if (!s) {
 258                         if (unlinkat(dirfd(d), de->d_name, 0) < 0)
 259                                 log_warning("Failed to remove /run/systemd/seats/%s: %m",
 260                                             de->d_name);
 261                         continue;
 262                 }
 263
 264                 k = seat_load(s);
 265                 if (k < 0)
 266                         r = k;
 267         }
 268
 269         return r;
 270 }
 271
 272 static int manager_enumerate_linger_users(Manager *m) {
 273         _cleanup_closedir_ DIR *d = NULL;
 274         struct dirent *de;
 275         int r = 0;
 276
 277         assert(m);
 278
 279         d = opendir("/var/lib/systemd/linger");
 280         if (!d) {
 281                 if (errno == ENOENT)
 282                         return 0;
 283
 284                 return log_error_errno(errno, "Failed to open /var/lib/systemd/linger/: %m");
 285         }
 286
 287         FOREACH_DIRENT(de, d, return -errno) {
 288                 int k;
 289
 290                 if (!dirent_is_file(de))
 291                         continue;
 292
 293                 k = manager_add_user_by_name(m, de->d_name, NULL);
 294                 if (k < 0) {
 295                         log_notice_errno(k, "Couldn't add lingering user %s: %m", de->d_name);
 296                         r = k;
 297                 }
 298         }
 299
 300         return r;
 301 }
 302
 303 static int manager_enumerate_users(Manager *m) {
 304         _cleanup_closedir_ DIR *d = NULL;
 305         struct dirent *de;
 306         int r, k;
 307
 308         assert(m);
 309
 310         /* Add lingering users */
 311         r = manager_enumerate_linger_users(m);
 312
 313         /* Read in user data stored on disk */
 314         d = opendir("/run/systemd/users");
 315         if (!d) {
 316                 if (errno == ENOENT)
 317                         return 0;
 318
 319                 return log_error_errno(errno, "Failed to open /run/systemd/users: %m");
 320         }
 321
 322         FOREACH_DIRENT(de, d, return -errno) {
 323                 User *u;
 324
 325                 if (!dirent_is_file(de))
 326                         continue;
 327
 328                 k = manager_add_user_by_name(m, de->d_name, &u);
 329                 if (k < 0) {
 330                         log_error_errno(k, "Failed to add user by file name %s: %m", de->d_name);
 331
 332                         r = k;
 333                         continue;
 334                 }
 335
 336                 user_add_to_gc_queue(u);
 337
 338                 k = user_load(u);
 339                 if (k < 0)
 340                         r = k;
 341         }
 342
 343         return r;
 344 }
 345
 346 static int parse_fdname(const char *fdname, char **session_id, dev_t *dev) {
 347         _cleanup_strv_free_ char **parts = NULL;
 348         _cleanup_free_ char *id = NULL;
 349         unsigned major, minor;
 350         int r;
 351
 352         parts = strv_split(fdname, "-");
 353         if (!parts)
 354                 return -ENOMEM;
 355         if (strv_length(parts) != 5)
 356                 return -EINVAL;
 357
 358         if (!streq(parts[0], "session"))
 359                 return -EINVAL;
 360
 361         id = strdup(parts[1]);
 362         if (!id)
 363                 return -ENOMEM;
 364
 365         if (!streq(parts[2], "device"))
 366                 return -EINVAL;
 367
 368         r = safe_atou(parts[3], &major);
 369         if (r < 0)
 370                 return r;
 371         r = safe_atou(parts[4], &minor);
 372         if (r < 0)
 373                 return r;
 374
 375         *dev = makedev(major, minor);
 376         *session_id = TAKE_PTR(id);
 377
 378         return 0;
 379 }
 380
 381 static int deliver_fd(Manager *m, const char *fdname, int fd) {
 382         _cleanup_free_ char *id = NULL;
 383         SessionDevice *sd;
 384         struct stat st;
 385         Session *s;
 386         dev_t dev;
 387         int r;
 388
 389         assert(m);
 390         assert(fd >= 0);
 391
 392         r = parse_fdname(fdname, &id, &dev);
 393         if (r < 0)
 394                 return log_debug_errno(r, "Failed to parse fd name %s: %m", fdname);
 395
 396         s = hashmap_get(m->sessions, id);
 397         if (!s)
 398                 /* If the session doesn't exist anymore, the associated session device attached to this fd
 399                  * doesn't either. Let's simply close this fd. */
 400                 return log_debug_errno(SYNTHETIC_ERRNO(ENXIO), "Failed to attach fd for unknown session: %s", id);
 401
 402         if (fstat(fd, &st) < 0)
 403                 /* The device is allowed to go away at a random point, in which case fstat() failing is
 404                  * expected. */
 405                 return log_debug_errno(errno, "Failed to stat device fd for session %s: %m", id);
 406
 407         if (!S_ISCHR(st.st_mode) || st.st_rdev != dev)
 408                 return log_debug_errno(SYNTHETIC_ERRNO(ENODEV), "Device fd doesn't point to the expected character device node");
 409
 410         sd = hashmap_get(s->devices, &dev);
 411         if (!sd)
 412                 /* Weird, we got an fd for a session device which wasn't recorded in the session state
 413                  * file... */
 414                 return log_warning_errno(SYNTHETIC_ERRNO(ENODEV), "Got fd for missing session device [%u:%u] in session %s",
 415                                          major(dev), minor(dev), s->id);
 416
 417         log_debug("Attaching fd to session device [%u:%u] for session %s",
 418                   major(dev), minor(dev), s->id);
 419
 420         session_device_attach_fd(sd, fd, s->was_active);
 421         return 0;
 422 }
 423
 424 static int manager_attach_fds(Manager *m) {
 425         _cleanup_strv_free_ char **fdnames = NULL;
 426         int n;
 427
 428         /* Upon restart, PID1 will send us back all fds of session devices that we previously opened. Each
 429          * file descriptor is associated with a given session. The session ids are passed through FDNAMES. */
 430
 431         n = sd_listen_fds_with_names(true, &fdnames);
 432         if (n < 0)
 433                 return log_warning_errno(n, "Failed to acquire passed fd list: %m");
 434         if (n == 0)
 435                 return 0;
 436
 437         for (int i = 0; i < n; i++) {
 438                 int fd = SD_LISTEN_FDS_START + i;
 439
 440                 if (deliver_fd(m, fdnames[i], fd) >= 0)
 441                         continue;
 442
 443                 /* Hmm, we couldn't deliver the fd to any session device object? If so, let's close the fd */
 444                 safe_close(fd);
 445
 446                 /* Remove from fdstore as well */
 447                 (void) sd_notifyf(false,
 448                                   "FDSTOREREMOVE=1\n"
 449                                   "FDNAME=%s", fdnames[i]);
 450         }
 451
 452         return 0;
 453 }
 454
 455 static int manager_enumerate_sessions(Manager *m) {
 456         _cleanup_closedir_ DIR *d = NULL;
 457         struct dirent *de;
 458         int r = 0, k;
 459
 460         assert(m);
 461
 462         /* Read in session data stored on disk */
 463         d = opendir("/run/systemd/sessions");
 464         if (!d) {
 465                 if (errno == ENOENT)
 466                         return 0;
 467
 468                 return log_error_errno(errno, "Failed to open /run/systemd/sessions: %m");
 469         }
 470
 471         FOREACH_DIRENT(de, d, return -errno) {
 472                 struct Session *s;
 473
 474                 if (!dirent_is_file(de))
 475                         continue;
 476
 477                 if (!session_id_valid(de->d_name)) {
 478                         log_warning("Invalid session file name '%s', ignoring.", de->d_name);
 479                         r = -EINVAL;
 480                         continue;
 481                 }
 482
 483                 k = manager_add_session(m, de->d_name, &s);
 484                 if (k < 0) {
 485                         log_error_errno(k, "Failed to add session by file name %s: %m", de->d_name);
 486                         r = k;
 487                         continue;
 488                 }
 489
 490                 session_add_to_gc_queue(s);
 491
 492                 k = session_load(s);
 493                 if (k < 0)
 494                         r = k;
 495         }
 496
 497         /* We might be restarted and PID1 could have sent us back the session device fds we previously
 498          * saved. */
 499         (void) manager_attach_fds(m);
 500
 501         return r;
 502 }
 503
 504 static int manager_enumerate_inhibitors(Manager *m) {
 505         _cleanup_closedir_ DIR *d = NULL;
 506         struct dirent *de;
 507         int r = 0;
 508
 509         assert(m);
 510
 511         d = opendir("/run/systemd/inhibit");
 512         if (!d) {
 513                 if (errno == ENOENT)
 514                         return 0;
 515
 516                 return log_error_errno(errno, "Failed to open /run/systemd/inhibit: %m");
 517         }
 518
 519         FOREACH_DIRENT(de, d, return -errno) {
 520                 int k;
 521                 Inhibitor *i;
 522
 523                 if (!dirent_is_file(de))
 524                         continue;
 525
 526                 k = manager_add_inhibitor(m, de->d_name, &i);
 527                 if (k < 0) {
 528                         log_notice_errno(k, "Couldn't add inhibitor %s: %m", de->d_name);
 529                         r = k;
 530                         continue;
 531                 }
 532
 533                 k = inhibitor_load(i);
 534                 if (k < 0)
 535                         r = k;
 536         }
 537
 538         return r;
 539 }
 540
 541 static int manager_dispatch_seat_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
 542         Manager *m = userdata;
 543
 544         assert(m);
 545         assert(device);
 546
 547         manager_process_seat_device(m, device);
 548         return 0;
 549 }
 550
 551 static int manager_dispatch_device_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
 552         Manager *m = userdata;
 553
 554         assert(m);
 555         assert(device);
 556
 557         manager_process_seat_device(m, device);
 558         return 0;
 559 }
 560
 561 static int manager_dispatch_vcsa_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
 562         Manager *m = userdata;
 563         const char *name;
 564
 565         assert(m);
 566         assert(device);
 567
 568         /* Whenever a VCSA device is removed try to reallocate our
 569          * VTs, to make sure our auto VTs never go away. */
 570
 571         if (sd_device_get_sysname(device, &name) >= 0 &&
 572             startswith(name, "vcsa") &&
 573             device_for_action(device, DEVICE_ACTION_REMOVE))
 574                 seat_preallocate_vts(m->seat0);
 575
 576         return 0;
 577 }
 578
 579 static int manager_dispatch_button_udev(sd_device_monitor *monitor, sd_device *device, void *userdata) {
 580         Manager *m = userdata;
 581
 582         assert(m);
 583         assert(device);
 584
 585         manager_process_button_device(m, device);
 586         return 0;
 587 }
 588
 589 static int manager_dispatch_console(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
 590         Manager *m = userdata;
 591
 592         assert(m);
 593         assert(m->seat0);
 594         assert(m->console_active_fd == fd);
 595
 596         seat_read_active_vt(m->seat0);
 597         return 0;
 598 }
 599
 600 static int manager_reserve_vt(Manager *m) {
 601         _cleanup_free_ char *p = NULL;
 602
 603         assert(m);
 604
 605         if (m->reserve_vt <= 0)
 606                 return 0;
 607
 608         if (asprintf(&p, "/dev/tty%u", m->reserve_vt) < 0)
 609                 return log_oom();
 610
 611         m->reserve_vt_fd = open(p, O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK);
 612         if (m->reserve_vt_fd < 0) {
 613
 614                 /* Don't complain on VT-less systems */
 615                 if (errno != ENOENT)
 616                         log_warning_errno(errno, "Failed to pin reserved VT: %m");
 617                 return -errno;
 618         }
 619
 620         return 0;
 621 }
 622
 623 static int manager_connect_bus(Manager *m) {
 624         int r;
 625
 626         assert(m);
 627         assert(!m->bus);
 628
 629         r = sd_bus_default_system(&m->bus);
 630         if (r < 0)
 631                 return log_error_errno(r, "Failed to connect to system bus: %m");
 632
 633         r = sd_bus_add_object_vtable(m->bus, NULL, "/org/freedesktop/login1", "org.freedesktop.login1.Manager", manager_vtable, m);
 634         if (r < 0)
 635                 return log_error_errno(r, "Failed to add manager object vtable: %m");
 636
 637         r = sd_bus_add_fallback_vtable(m->bus, NULL, "/org/freedesktop/login1/seat", "org.freedesktop.login1.Seat", seat_vtable, seat_object_find, m);
 638         if (r < 0)
 639                 return log_error_errno(r, "Failed to add seat object vtable: %m");
 640
 641         r = sd_bus_add_node_enumerator(m->bus, NULL, "/org/freedesktop/login1/seat", seat_node_enumerator, m);
 642         if (r < 0)
 643                 return log_error_errno(r, "Failed to add seat enumerator: %m");
 644
 645         r = sd_bus_add_fallback_vtable(m->bus, NULL, "/org/freedesktop/login1/session", "org.freedesktop.login1.Session", session_vtable, session_object_find, m);
 646         if (r < 0)
 647                 return log_error_errno(r, "Failed to add session object vtable: %m");
 648
 649         r = sd_bus_add_node_enumerator(m->bus, NULL, "/org/freedesktop/login1/session", session_node_enumerator, m);
 650         if (r < 0)
 651                 return log_error_errno(r, "Failed to add session enumerator: %m");
 652
 653         r = sd_bus_add_fallback_vtable(m->bus, NULL, "/org/freedesktop/login1/user", "org.freedesktop.login1.User", user_vtable, user_object_find, m);
 654         if (r < 0)
 655                 return log_error_errno(r, "Failed to add user object vtable: %m");
 656
 657         r = sd_bus_add_node_enumerator(m->bus, NULL, "/org/freedesktop/login1/user", user_node_enumerator, m);
 658         if (r < 0)
 659                 return log_error_errno(r, "Failed to add user enumerator: %m");
 660
 661         r = sd_bus_match_signal_async(
 662                         m->bus,
 663                         NULL,
 664                         "org.freedesktop.systemd1",
 665                         "/org/freedesktop/systemd1",
 666                         "org.freedesktop.systemd1.Manager",
 667                         "JobRemoved",
 668                         match_job_removed, NULL, m);
 669         if (r < 0)
 670                 return log_error_errno(r, "Failed to request match for JobRemoved: %m");
 671
 672         r = sd_bus_match_signal_async(
 673                         m->bus,
 674                         NULL,
 675                         "org.freedesktop.systemd1",
 676                         "/org/freedesktop/systemd1",
 677                         "org.freedesktop.systemd1.Manager",
 678                         "UnitRemoved",
 679                         match_unit_removed, NULL, m);
 680         if (r < 0)
 681                 return log_error_errno(r, "Failed to request match for UnitRemoved: %m");
 682
 683         r = sd_bus_match_signal_async(
 684                         m->bus,
 685                         NULL,
 686                         "org.freedesktop.systemd1",
 687                         NULL,
 688                         "org.freedesktop.DBus.Properties",
 689                         "PropertiesChanged",
 690                         match_properties_changed, NULL, m);
 691         if (r < 0)
 692                 return log_error_errno(r, "Failed to request match for PropertiesChanged: %m");
 693
 694         r = sd_bus_match_signal_async(
 695                         m->bus,
 696                         NULL,
 697                         "org.freedesktop.systemd1",
 698                         "/org/freedesktop/systemd1",
 699                         "org.freedesktop.systemd1.Manager",
 700                         "Reloading",
 701                         match_reloading, NULL, m);
 702         if (r < 0)
 703                 return log_error_errno(r, "Failed to request match for Reloading: %m");
 704
 705         r = sd_bus_call_method_async(
 706                         m->bus,
 707                         NULL,
 708                         "org.freedesktop.systemd1",
 709                         "/org/freedesktop/systemd1",
 710                         "org.freedesktop.systemd1.Manager",
 711                         "Subscribe",
 712                         NULL, NULL,
 713                         NULL);
 714         if (r < 0)
 715                 return log_error_errno(r, "Failed to enable subscription: %m");
 716
 717         r = sd_bus_request_name_async(m->bus, NULL, "org.freedesktop.login1", 0, NULL, NULL);
 718         if (r < 0)
 719                 return log_error_errno(r, "Failed to request name: %m");
 720
 721         r = sd_bus_attach_event(m->bus, m->event, SD_EVENT_PRIORITY_NORMAL);
 722         if (r < 0)
 723                 return log_error_errno(r, "Failed to attach bus to event loop: %m");
 724
 725         return 0;
 726 }
 727
 728 static int manager_vt_switch(sd_event_source *src, const struct signalfd_siginfo *si, void *data) {
 729         Manager *m = data;
 730         Session *active, *iter;
 731
 732         /*
 733          * We got a VT-switch signal and we have to acknowledge it immediately.
 734          * Preferably, we'd just use m->seat0->active->vtfd, but unfortunately,
 735          * old user-space might run multiple sessions on a single VT, *sigh*.
 736          * Therefore, we have to iterate all sessions and find one with a vtfd
 737          * on the requested VT.
 738          * As only VTs with active controllers have VT_PROCESS set, our current
 739          * notion of the active VT might be wrong (for instance if the switch
 740          * happens while we setup VT_PROCESS). Therefore, read the current VT
 741          * first and then use s->active->vtnr as reference. Note that this is
 742          * not racy, as no further VT-switch can happen as long as we're in
 743          * synchronous VT_PROCESS mode.
 744          */
 745
 746         assert(m->seat0);
 747         seat_read_active_vt(m->seat0);
 748
 749         active = m->seat0->active;
 750         if (!active || active->vtnr < 1) {
 751                 _cleanup_close_ int fd = -1;
 752                 int r;
 753
 754                 /* We are requested to acknowledge the VT-switch signal by the kernel but
 755                  * there's no registered sessions for the current VT. Normally this
 756                  * shouldn't happen but something wrong might have happened when we tried
 757                  * to release the VT. Better be safe than sorry, and try to release the VT
 758                  * one more time otherwise the user will be locked with the current VT. */
 759
 760                 log_warning("Received VT_PROCESS signal without a registered session, restoring VT.");
 761
 762                 /* At this point we only have the kernel mapping for referring to the
 763                  * current VT. */
 764                 fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK);
 765                 if (fd < 0) {
 766                         log_warning_errno(fd, "Failed to open, ignoring: %m");
 767                         return 0;
 768                 }
 769
 770                 r = vt_release(fd, true);
 771                 if (r < 0)
 772                         log_warning_errno(r, "Failed to release VT, ignoring: %m");
 773
 774                 return 0;
 775         }
 776
 777         if (active->vtfd >= 0) {
 778                 session_leave_vt(active);
 779         } else {
 780                 LIST_FOREACH(sessions_by_seat, iter, m->seat0->sessions) {
 781                         if (iter->vtnr == active->vtnr && iter->vtfd >= 0) {
 782                                 session_leave_vt(iter);
 783                                 break;
 784                         }
 785                 }
 786         }
 787
 788         return 0;
 789 }
 790
 791 static int manager_connect_console(Manager *m) {
 792         int r;
 793
 794         assert(m);
 795         assert(m->console_active_fd < 0);
 796
 797         /* On certain systems (such as S390, Xen, and containers) /dev/tty0 does not exist (as there is no VC), so
 798          * don't fail if we can't open it. */
 799
 800         if (access("/dev/tty0", F_OK) < 0)
 801                 return 0;
 802
 803         m->console_active_fd = open("/sys/class/tty/tty0/active", O_RDONLY|O_NOCTTY|O_CLOEXEC);
 804         if (m->console_active_fd < 0) {
 805
 806                 /* On some systems /dev/tty0 may exist even though /sys/class/tty/tty0 does not. These are broken, but
 807                  * common. Let's complain but continue anyway. */
 808                 if (errno == ENOENT) {
 809                         log_warning_errno(errno, "System has /dev/tty0 but not /sys/class/tty/tty0/active which is broken, ignoring: %m");
 810                         return 0;
 811                 }
 812
 813                 return log_error_errno(errno, "Failed to open /sys/class/tty/tty0/active: %m");
 814         }
 815
 816         r = sd_event_add_io(m->event, &m->console_active_event_source, m->console_active_fd, 0, manager_dispatch_console, m);
 817         if (r < 0)
 818                 return log_error_errno(r, "Failed to watch foreground console: %m");
 819
 820         /*
 821          * SIGRTMIN is used as global VT-release signal, SIGRTMIN + 1 is used
 822          * as VT-acquire signal. We ignore any acquire-events (yes, we still
 823          * have to provide a valid signal-number for it!) and acknowledge all
 824          * release events immediately.
 825          */
 826
 827         if (SIGRTMIN + 1 > SIGRTMAX)
 828                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 829                                        "Not enough real-time signals available: %u-%u",
 830                                        SIGRTMIN, SIGRTMAX);
 831
 832         assert_se(ignore_signals(SIGRTMIN + 1, -1) >= 0);
 833         assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGRTMIN, -1) >= 0);
 834
 835         r = sd_event_add_signal(m->event, NULL, SIGRTMIN, manager_vt_switch, m);
 836         if (r < 0)
 837                 return log_error_errno(r, "Failed to subscribe to signal: %m");
 838
 839         return 0;
 840 }
 841
 842 static int manager_connect_udev(Manager *m) {
 843         int r;
 844
 845         assert(m);
 846         assert(!m->device_seat_monitor);
 847         assert(!m->device_monitor);
 848         assert(!m->device_vcsa_monitor);
 849         assert(!m->device_button_monitor);
 850
 851         r = sd_device_monitor_new(&m->device_seat_monitor);
 852         if (r < 0)
 853                 return r;
 854
 855         r = sd_device_monitor_filter_add_match_tag(m->device_seat_monitor, "master-of-seat");
 856         if (r < 0)
 857                 return r;
 858
 859         r = sd_device_monitor_attach_event(m->device_seat_monitor, m->event);
 860         if (r < 0)
 861                 return r;
 862
 863         r = sd_device_monitor_start(m->device_seat_monitor, manager_dispatch_seat_udev, m);
 864         if (r < 0)
 865                 return r;
 866
 867         (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_seat_monitor), "logind-seat-monitor");
 868
 869         r = sd_device_monitor_new(&m->device_monitor);
 870         if (r < 0)
 871                 return r;
 872
 873         r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_monitor, "input", NULL);
 874         if (r < 0)
 875                 return r;
 876
 877         r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_monitor, "graphics", NULL);
 878         if (r < 0)
 879                 return r;
 880
 881         r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_monitor, "drm", NULL);
 882         if (r < 0)
 883                 return r;
 884
 885         r = sd_device_monitor_attach_event(m->device_monitor, m->event);
 886         if (r < 0)
 887                 return r;
 888
 889         r = sd_device_monitor_start(m->device_monitor, manager_dispatch_device_udev, m);
 890         if (r < 0)
 891                 return r;
 892
 893         (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_monitor), "logind-device-monitor");
 894
 895         /* Don't watch keys if nobody cares */
 896         if (!manager_all_buttons_ignored(m)) {
 897                 r = sd_device_monitor_new(&m->device_button_monitor);
 898                 if (r < 0)
 899                         return r;
 900
 901                 r = sd_device_monitor_filter_add_match_tag(m->device_button_monitor, "power-switch");
 902                 if (r < 0)
 903                         return r;
 904
 905                 r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_button_monitor, "input", NULL);
 906                 if (r < 0)
 907                         return r;
 908
 909                 r = sd_device_monitor_attach_event(m->device_button_monitor, m->event);
 910                 if (r < 0)
 911                         return r;
 912
 913                 r = sd_device_monitor_start(m->device_button_monitor, manager_dispatch_button_udev, m);
 914                 if (r < 0)
 915                         return r;
 916
 917                 (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_button_monitor), "logind-button-monitor");
 918         }
 919
 920         /* Don't bother watching VCSA devices, if nobody cares */
 921         if (m->n_autovts > 0 && m->console_active_fd >= 0) {
 922
 923                 r = sd_device_monitor_new(&m->device_vcsa_monitor);
 924                 if (r < 0)
 925                         return r;
 926
 927                 r = sd_device_monitor_filter_add_match_subsystem_devtype(m->device_vcsa_monitor, "vc", NULL);
 928                 if (r < 0)
 929                         return r;
 930
 931                 r = sd_device_monitor_attach_event(m->device_vcsa_monitor, m->event);
 932                 if (r < 0)
 933                         return r;
 934
 935                 r = sd_device_monitor_start(m->device_vcsa_monitor, manager_dispatch_vcsa_udev, m);
 936                 if (r < 0)
 937                         return r;
 938
 939                 (void) sd_event_source_set_description(sd_device_monitor_get_event_source(m->device_vcsa_monitor), "logind-vcsa-monitor");
 940         }
 941
 942         return 0;
 943 }
 944
 945 static void manager_gc(Manager *m, bool drop_not_started) {
 946         Seat *seat;
 947         Session *session;
 948         User *user;
 949
 950         assert(m);
 951
 952         while ((seat = m->seat_gc_queue)) {
 953                 LIST_REMOVE(gc_queue, m->seat_gc_queue, seat);
 954                 seat->in_gc_queue = false;
 955
 956                 if (seat_may_gc(seat, drop_not_started)) {
 957                         seat_stop(seat, false);
 958                         seat_free(seat);
 959                 }
 960         }
 961
 962         while ((session = m->session_gc_queue)) {
 963                 LIST_REMOVE(gc_queue, m->session_gc_queue, session);
 964                 session->in_gc_queue = false;
 965
 966                 /* First, if we are not closing yet, initiate stopping */
 967                 if (session_may_gc(session, drop_not_started) &&
 968                     session_get_state(session) != SESSION_CLOSING)
 969                         (void) session_stop(session, false);
 970
 971                 /* Normally, this should make the session referenced
 972                  * again, if it doesn't then let's get rid of it
 973                  * immediately */
 974                 if (session_may_gc(session, drop_not_started)) {
 975                         (void) session_finalize(session);
 976                         session_free(session);
 977                 }
 978         }
 979
 980         while ((user = m->user_gc_queue)) {
 981                 LIST_REMOVE(gc_queue, m->user_gc_queue, user);
 982                 user->in_gc_queue = false;
 983
 984                 /* First step: queue stop jobs */
 985                 if (user_may_gc(user, drop_not_started))
 986                         (void) user_stop(user, false);
 987
 988                 /* Second step: finalize user */
 989                 if (user_may_gc(user, drop_not_started)) {
 990                         (void) user_finalize(user);
 991                         user_free(user);
 992                 }
 993         }
 994 }
 995
 996 static int manager_dispatch_idle_action(sd_event_source *s, uint64_t t, void *userdata) {
 997         Manager *m = userdata;
 998         struct dual_timestamp since;
 999         usec_t n, elapse;
1000         int r;
1001
1002         assert(m);
1003
1004         if (m->idle_action == HANDLE_IGNORE ||
1005             m->idle_action_usec <= 0)
1006                 return 0;
1007
1008         n = now(CLOCK_MONOTONIC);
1009
1010         r = manager_get_idle_hint(m, &since);
1011         if (r <= 0)
1012                 /* Not idle. Let's check if after a timeout it might be idle then. */
1013                 elapse = n + m->idle_action_usec;
1014         else {
1015                 /* Idle! Let's see if it's time to do something, or if
1016                  * we shall sleep for longer. */
1017
1018                 if (n >= since.monotonic + m->idle_action_usec &&
1019                     (m->idle_action_not_before_usec <= 0 || n >= m->idle_action_not_before_usec + m->idle_action_usec)) {
1020                         log_info("System idle. Taking action.");
1021
1022                         manager_handle_action(m, 0, m->idle_action, false, false);
1023                         m->idle_action_not_before_usec = n;
1024                 }
1025
1026                 elapse = MAX(since.monotonic, m->idle_action_not_before_usec) + m->idle_action_usec;
1027         }
1028
1029         if (!m->idle_action_event_source) {
1030
1031                 r = sd_event_add_time(
1032                                 m->event,
1033                                 &m->idle_action_event_source,
1034                                 CLOCK_MONOTONIC,
1035                                 elapse, USEC_PER_SEC*30,
1036                                 manager_dispatch_idle_action, m);
1037                 if (r < 0)
1038                         return log_error_errno(r, "Failed to add idle event source: %m");
1039
1040                 r = sd_event_source_set_priority(m->idle_action_event_source, SD_EVENT_PRIORITY_IDLE+10);
1041                 if (r < 0)
1042                         return log_error_errno(r, "Failed to set idle event source priority: %m");
1043         } else {
1044                 r = sd_event_source_set_time(m->idle_action_event_source, elapse);
1045                 if (r < 0)
1046                         return log_error_errno(r, "Failed to set idle event timer: %m");
1047
1048                 r = sd_event_source_set_enabled(m->idle_action_event_source, SD_EVENT_ONESHOT);
1049                 if (r < 0)
1050                         return log_error_errno(r, "Failed to enable idle event timer: %m");
1051         }
1052
1053         return 0;
1054 }
1055
1056 static int manager_dispatch_reload_signal(sd_event_source *s, const struct signalfd_siginfo *si, void *userdata) {
1057         Manager *m = userdata;
1058         int r;
1059
1060         manager_reset_config(m);
1061         r = manager_parse_config_file(m);
1062         if (r < 0)
1063                 log_warning_errno(r, "Failed to parse config file, using defaults: %m");
1064         else
1065                 log_info("Config file reloaded.");
1066
1067         return 0;
1068 }
1069
1070 static int manager_startup(Manager *m) {
1071         int r;
1072         Seat *seat;
1073         Session *session;
1074         User *user;
1075         Button *button;
1076         Inhibitor *inhibitor;
1077         Iterator i;
1078
1079         assert(m);
1080
1081         r = sd_event_add_signal(m->event, NULL, SIGHUP, manager_dispatch_reload_signal, m);
1082         if (r < 0)
1083                 return log_error_errno(r, "Failed to register SIGHUP handler: %m");
1084
1085         /* Connect to utmp */
1086         manager_connect_utmp(m);
1087
1088         /* Connect to console */
1089         r = manager_connect_console(m);
1090         if (r < 0)
1091                 return r;
1092
1093         /* Connect to udev */
1094         r = manager_connect_udev(m);
1095         if (r < 0)
1096                 return log_error_errno(r, "Failed to create udev watchers: %m");
1097
1098         /* Connect to the bus */
1099         r = manager_connect_bus(m);
1100         if (r < 0)
1101                 return r;
1102
1103         /* Instantiate magic seat 0 */
1104         r = manager_add_seat(m, "seat0", &m->seat0);
1105         if (r < 0)
1106                 return log_error_errno(r, "Failed to add seat0: %m");
1107
1108         r = manager_set_lid_switch_ignore(m, 0 + m->holdoff_timeout_usec);
1109         if (r < 0)
1110                 log_warning_errno(r, "Failed to set up lid switch ignore event source: %m");
1111
1112         /* Deserialize state */
1113         r = manager_enumerate_devices(m);
1114         if (r < 0)
1115                 log_warning_errno(r, "Device enumeration failed: %m");
1116
1117         r = manager_enumerate_seats(m);
1118         if (r < 0)
1119                 log_warning_errno(r, "Seat enumeration failed: %m");
1120
1121         r = manager_enumerate_users(m);
1122         if (r < 0)
1123                 log_warning_errno(r, "User enumeration failed: %m");
1124
1125         r = manager_enumerate_sessions(m);
1126         if (r < 0)
1127                 log_warning_errno(r, "Session enumeration failed: %m");
1128
1129         r = manager_enumerate_inhibitors(m);
1130         if (r < 0)
1131                 log_warning_errno(r, "Inhibitor enumeration failed: %m");
1132
1133         r = manager_enumerate_buttons(m);
1134         if (r < 0)
1135                 log_warning_errno(r, "Button enumeration failed: %m");
1136
1137         /* Remove stale objects before we start them */
1138         manager_gc(m, false);
1139
1140         /* Reserve the special reserved VT */
1141         manager_reserve_vt(m);
1142
1143         /* Read in utmp if it exists */
1144         manager_read_utmp(m);
1145
1146         /* And start everything */
1147         HASHMAP_FOREACH(seat, m->seats, i)
1148                 (void) seat_start(seat);
1149
1150         HASHMAP_FOREACH(user, m->users, i)
1151                 (void) user_start(user);
1152
1153         HASHMAP_FOREACH(session, m->sessions, i)
1154                 (void) session_start(session, NULL, NULL);
1155
1156         HASHMAP_FOREACH(inhibitor, m->inhibitors, i)
1157                 inhibitor_start(inhibitor);
1158
1159         HASHMAP_FOREACH(button, m->buttons, i)
1160                 button_check_switches(button);
1161
1162         manager_dispatch_idle_action(NULL, 0, m);
1163
1164         return 0;
1165 }
1166
1167 static int manager_run(Manager *m) {
1168         int r;
1169
1170         assert(m);
1171
1172         for (;;) {
1173                 r = sd_event_get_state(m->event);
1174                 if (r < 0)
1175                         return r;
1176                 if (r == SD_EVENT_FINISHED)
1177                         return 0;
1178
1179                 manager_gc(m, true);
1180
1181                 r = manager_dispatch_delayed(m, false);
1182                 if (r < 0)
1183                         return r;
1184                 if (r > 0)
1185                         continue;
1186
1187                 r = sd_event_run(m->event, (uint64_t) -1);
1188                 if (r < 0)
1189                         return r;
1190         }
1191 }
1192
1193 static int run(int argc, char *argv[]) {
1194         _cleanup_(manager_unrefp) Manager *m = NULL;
1195         int r;
1196
1197         log_set_facility(LOG_AUTH);
1198         log_setup_service();
1199
1200         umask(0022);
1201
1202         if (argc != 1) {
1203                 log_error("This program takes no arguments.");
1204                 return -EINVAL;
1205         }
1206
1207         r = mac_selinux_init();
1208         if (r < 0)
1209                 return log_error_errno(r, "Could not initialize labelling: %m");
1210
1211         /* Always create the directories people can create inotify watches in. Note that some applications might check
1212          * for the existence of /run/systemd/seats/ to determine whether logind is available, so please always make
1213          * sure these directories are created early on and unconditionally. */
1214         (void) mkdir_label("/run/systemd/seats", 0755);
1215         (void) mkdir_label("/run/systemd/users", 0755);
1216         (void) mkdir_label("/run/systemd/sessions", 0755);
1217
1218         assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGHUP, SIGTERM, SIGINT, -1) >= 0);
1219
1220         r = manager_new(&m);
1221         if (r < 0)
1222                 return log_error_errno(r, "Failed to allocate manager object: %m");
1223
1224         (void) manager_parse_config_file(m);
1225
1226         r = manager_startup(m);
1227         if (r < 0)
1228                 return log_error_errno(r, "Failed to fully start up daemon: %m");
1229
1230         log_debug("systemd-logind running as pid "PID_FMT, getpid_cached());
1231         (void) sd_notify(false,
1232                          "READY=1\n"
1233                          "STATUS=Processing requests...");
1234
1235         r = manager_run(m);
1236
1237         log_debug("systemd-logind stopped as pid "PID_FMT, getpid_cached());
1238         (void) sd_notify(false,
1239                          "STOPPING=1\n"
1240                          "STATUS=Shutting down...");
1241
1242         return r;
1243 }
1244
1245 DEFINE_MAIN_FUNCTION(run);