src/login/logind.c

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