src/login/logind-core.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <fcntl.h>
   4 #include <sys/ioctl.h>
   5 #include <sys/types.h>
   6 #include <linux/vt.h>
   7
   8 #include "sd-device.h"
   9
  10 #include "alloc-util.h"
  11 #include "bus-error.h"
  12 #include "bus-util.h"
  13 #include "cgroup-util.h"
  14 #include "conf-parser.h"
  15 #include "device-util.h"
  16 #include "efi-loader.h"
  17 #include "errno-util.h"
  18 #include "fd-util.h"
  19 #include "limits-util.h"
  20 #include "logind.h"
  21 #include "parse-util.h"
  22 #include "path-util.h"
  23 #include "process-util.h"
  24 #include "stdio-util.h"
  25 #include "strv.h"
  26 #include "terminal-util.h"
  27 #include "udev-util.h"
  28 #include "user-util.h"
  29 #include "userdb.h"
  30 #include "utmp-wtmp.h"
  31
  32 void manager_reset_config(Manager *m) {
  33         assert(m);
  34
  35         m->n_autovts = 6;
  36         m->reserve_vt = 6;
  37         m->remove_ipc = true;
  38         m->inhibit_delay_max = 5 * USEC_PER_SEC;
  39         m->user_stop_delay = 10 * USEC_PER_SEC;
  40
  41         m->handle_power_key = HANDLE_POWEROFF;
  42         m->handle_power_key_long_press = HANDLE_IGNORE;
  43         m->handle_reboot_key = HANDLE_REBOOT;
  44         m->handle_reboot_key_long_press = HANDLE_POWEROFF;
  45         m->handle_suspend_key = HANDLE_SUSPEND;
  46         m->handle_suspend_key_long_press = HANDLE_HIBERNATE;
  47         m->handle_hibernate_key = HANDLE_HIBERNATE;
  48         m->handle_hibernate_key_long_press = HANDLE_IGNORE;
  49
  50         m->handle_lid_switch = HANDLE_SUSPEND;
  51         m->handle_lid_switch_ep = _HANDLE_ACTION_INVALID;
  52         m->handle_lid_switch_docked = HANDLE_IGNORE;
  53
  54         m->power_key_ignore_inhibited = false;
  55         m->suspend_key_ignore_inhibited = false;
  56         m->hibernate_key_ignore_inhibited = false;
  57         m->lid_switch_ignore_inhibited = true;
  58         m->reboot_key_ignore_inhibited = false;
  59
  60         m->holdoff_timeout_usec = 30 * USEC_PER_SEC;
  61
  62         m->idle_action_usec = 30 * USEC_PER_MINUTE;
  63         m->idle_action = HANDLE_IGNORE;
  64
  65         m->runtime_dir_size = physical_memory_scale(10U, 100U); /* 10% */
  66         m->runtime_dir_inodes = DIV_ROUND_UP(m->runtime_dir_size, 4096); /* 4k per inode */
  67         m->sessions_max = 8192;
  68         m->inhibitors_max = 8192;
  69
  70         m->kill_user_processes = KILL_USER_PROCESSES;
  71
  72         m->kill_only_users = strv_free(m->kill_only_users);
  73         m->kill_exclude_users = strv_free(m->kill_exclude_users);
  74 }
  75
  76 int manager_parse_config_file(Manager *m) {
  77         assert(m);
  78
  79         return config_parse_many_nulstr(
  80                         PKGSYSCONFDIR "/logind.conf",
  81                         CONF_PATHS_NULSTR("systemd/logind.conf.d"),
  82                         "Login\0",
  83                         config_item_perf_lookup, logind_gperf_lookup,
  84                         CONFIG_PARSE_WARN, m,
  85                         NULL);
  86 }
  87
  88 int manager_add_device(Manager *m, const char *sysfs, bool master, Device **ret_device) {
  89         Device *d;
  90
  91         assert(m);
  92         assert(sysfs);
  93
  94         d = hashmap_get(m->devices, sysfs);
  95         if (d)
  96                 /* we support adding master-flags, but not removing them */
  97                 d->master = d->master || master;
  98         else {
  99                 d = device_new(m, sysfs, master);
 100                 if (!d)
 101                         return -ENOMEM;
 102         }
 103
 104         if (ret_device)
 105                 *ret_device = d;
 106
 107         return 0;
 108 }
 109
 110 int manager_add_seat(Manager *m, const char *id, Seat **ret_seat) {
 111         Seat *s;
 112         int r;
 113
 114         assert(m);
 115         assert(id);
 116
 117         s = hashmap_get(m->seats, id);
 118         if (!s) {
 119                 r = seat_new(&s, m, id);
 120                 if (r < 0)
 121                         return r;
 122         }
 123
 124         if (ret_seat)
 125                 *ret_seat = s;
 126
 127         return 0;
 128 }
 129
 130 int manager_add_session(Manager *m, const char *id, Session **ret_session) {
 131         Session *s;
 132         int r;
 133
 134         assert(m);
 135         assert(id);
 136
 137         s = hashmap_get(m->sessions, id);
 138         if (!s) {
 139                 r = session_new(&s, m, id);
 140                 if (r < 0)
 141                         return r;
 142         }
 143
 144         if (ret_session)
 145                 *ret_session = s;
 146
 147         return 0;
 148 }
 149
 150 int manager_add_user(
 151                 Manager *m,
 152                 UserRecord *ur,
 153                 User **ret_user) {
 154
 155         User *u;
 156         int r;
 157
 158         assert(m);
 159         assert(ur);
 160
 161         u = hashmap_get(m->users, UID_TO_PTR(ur->uid));
 162         if (!u) {
 163                 r = user_new(&u, m, ur);
 164                 if (r < 0)
 165                         return r;
 166         }
 167
 168         if (ret_user)
 169                 *ret_user = u;
 170
 171         return 0;
 172 }
 173
 174 int manager_add_user_by_name(
 175                 Manager *m,
 176                 const char *name,
 177                 User **ret_user) {
 178
 179         _cleanup_(user_record_unrefp) UserRecord *ur = NULL;
 180         int r;
 181
 182         assert(m);
 183         assert(name);
 184
 185         r = userdb_by_name(name, USERDB_SUPPRESS_SHADOW, &ur);
 186         if (r < 0)
 187                 return r;
 188
 189         return manager_add_user(m, ur, ret_user);
 190 }
 191
 192 int manager_add_user_by_uid(
 193                 Manager *m,
 194                 uid_t uid,
 195                 User **ret_user) {
 196
 197         _cleanup_(user_record_unrefp) UserRecord *ur = NULL;
 198         int r;
 199
 200         assert(m);
 201         assert(uid_is_valid(uid));
 202
 203         r = userdb_by_uid(uid, USERDB_SUPPRESS_SHADOW, &ur);
 204         if (r < 0)
 205                 return r;
 206
 207         return manager_add_user(m, ur, ret_user);
 208 }
 209
 210 int manager_add_inhibitor(Manager *m, const char* id, Inhibitor **ret) {
 211         Inhibitor *i;
 212         int r;
 213
 214         assert(m);
 215         assert(id);
 216
 217         i = hashmap_get(m->inhibitors, id);
 218         if (!i) {
 219                 r = inhibitor_new(&i, m, id);
 220                 if (r < 0)
 221                         return r;
 222         }
 223
 224         if (ret)
 225                 *ret = i;
 226
 227         return 0;
 228 }
 229
 230 int manager_add_button(Manager *m, const char *name, Button **ret_button) {
 231         Button *b;
 232
 233         assert(m);
 234         assert(name);
 235
 236         b = hashmap_get(m->buttons, name);
 237         if (!b) {
 238                 b = button_new(m, name);
 239                 if (!b)
 240                         return -ENOMEM;
 241         }
 242
 243         if (ret_button)
 244                 *ret_button = b;
 245
 246         return 0;
 247 }
 248
 249 int manager_process_seat_device(Manager *m, sd_device *d) {
 250         Device *device;
 251         int r;
 252
 253         assert(m);
 254
 255         if (device_for_action(d, SD_DEVICE_REMOVE) ||
 256             sd_device_has_current_tag(d, "seat") <= 0) {
 257                 const char *syspath;
 258
 259                 r = sd_device_get_syspath(d, &syspath);
 260                 if (r < 0)
 261                         return 0;
 262
 263                 device = hashmap_get(m->devices, syspath);
 264                 if (!device)
 265                         return 0;
 266
 267                 seat_add_to_gc_queue(device->seat);
 268                 device_free(device);
 269
 270         } else {
 271                 const char *sn, *syspath;
 272                 bool master;
 273                 Seat *seat;
 274
 275                 if (sd_device_get_property_value(d, "ID_SEAT", &sn) < 0 || isempty(sn))
 276                         sn = "seat0";
 277
 278                 if (!seat_name_is_valid(sn)) {
 279                         log_device_warning(d, "Device with invalid seat name %s found, ignoring.", sn);
 280                         return 0;
 281                 }
 282
 283                 seat = hashmap_get(m->seats, sn);
 284                 master = sd_device_has_current_tag(d, "master-of-seat") > 0;
 285
 286                 /* Ignore non-master devices for unknown seats */
 287                 if (!master && !seat)
 288                         return 0;
 289
 290                 r = sd_device_get_syspath(d, &syspath);
 291                 if (r < 0)
 292                         return r;
 293
 294                 r = manager_add_device(m, syspath, master, &device);
 295                 if (r < 0)
 296                         return r;
 297
 298                 if (!seat) {
 299                         r = manager_add_seat(m, sn, &seat);
 300                         if (r < 0) {
 301                                 if (!device->seat)
 302                                         device_free(device);
 303
 304                                 return r;
 305                         }
 306                 }
 307
 308                 device_attach(device, seat);
 309                 seat_start(seat);
 310         }
 311
 312         return 0;
 313 }
 314
 315 int manager_process_button_device(Manager *m, sd_device *d) {
 316         const char *sysname;
 317         Button *b;
 318         int r;
 319
 320         assert(m);
 321
 322         r = sd_device_get_sysname(d, &sysname);
 323         if (r < 0)
 324                 return r;
 325
 326         if (device_for_action(d, SD_DEVICE_REMOVE) ||
 327             sd_device_has_current_tag(d, "power-switch") <= 0) {
 328
 329                 b = hashmap_get(m->buttons, sysname);
 330                 if (!b)
 331                         return 0;
 332
 333                 button_free(b);
 334
 335         } else {
 336                 const char *sn;
 337
 338                 r = manager_add_button(m, sysname, &b);
 339                 if (r < 0)
 340                         return r;
 341
 342                 if (sd_device_get_property_value(d, "ID_SEAT", &sn) < 0 || isempty(sn))
 343                         sn = "seat0";
 344
 345                 button_set_seat(b, sn);
 346
 347                 r = button_open(b);
 348                 if (r < 0) /* event device doesn't have any keys or switches relevant to us? (or any other error
 349                             * opening the device?) let's close the button again. */
 350                         button_free(b);
 351         }
 352
 353         return 0;
 354 }
 355
 356 int manager_get_session_by_pid(Manager *m, pid_t pid, Session **ret) {
 357         _cleanup_free_ char *unit = NULL;
 358         Session *s;
 359         int r;
 360
 361         assert(m);
 362
 363         if (!pid_is_valid(pid))
 364                 return -EINVAL;
 365
 366         s = hashmap_get(m->sessions_by_leader, PID_TO_PTR(pid));
 367         if (!s) {
 368                 r = cg_pid_get_unit(pid, &unit);
 369                 if (r >= 0)
 370                         s = hashmap_get(m->session_units, unit);
 371         }
 372
 373         if (ret)
 374                 *ret = s;
 375
 376         return !!s;
 377 }
 378
 379 int manager_get_user_by_pid(Manager *m, pid_t pid, User **ret) {
 380         _cleanup_free_ char *unit = NULL;
 381         User *u = NULL;
 382         int r;
 383
 384         assert(m);
 385
 386         if (!pid_is_valid(pid))
 387                 return -EINVAL;
 388
 389         r = cg_pid_get_slice(pid, &unit);
 390         if (r >= 0)
 391                 u = hashmap_get(m->user_units, unit);
 392
 393         if (ret)
 394                 *ret = u;
 395
 396         return !!u;
 397 }
 398
 399 int manager_get_idle_hint(Manager *m, dual_timestamp *t) {
 400         Session *s;
 401         bool idle_hint;
 402         dual_timestamp ts = DUAL_TIMESTAMP_NULL;
 403
 404         assert(m);
 405
 406         idle_hint = !manager_is_inhibited(m, INHIBIT_IDLE, INHIBIT_BLOCK, t, false, false, 0, NULL);
 407
 408         HASHMAP_FOREACH(s, m->sessions) {
 409                 dual_timestamp k;
 410                 int ih;
 411
 412                 ih = session_get_idle_hint(s, &k);
 413                 if (ih < 0)
 414                         return ih;
 415
 416                 if (!ih) {
 417                         if (!idle_hint) {
 418                                 if (k.monotonic < ts.monotonic)
 419                                         ts = k;
 420                         } else {
 421                                 idle_hint = false;
 422                                 ts = k;
 423                         }
 424                 } else if (idle_hint) {
 425
 426                         if (k.monotonic > ts.monotonic)
 427                                 ts = k;
 428                 }
 429         }
 430
 431         if (t)
 432                 *t = ts;
 433
 434         return idle_hint;
 435 }
 436
 437 bool manager_shall_kill(Manager *m, const char *user) {
 438         assert(m);
 439         assert(user);
 440
 441         if (!m->kill_exclude_users && streq(user, "root"))
 442                 return false;
 443
 444         if (strv_contains(m->kill_exclude_users, user))
 445                 return false;
 446
 447         if (!strv_isempty(m->kill_only_users))
 448                 return strv_contains(m->kill_only_users, user);
 449
 450         return m->kill_user_processes;
 451 }
 452
 453 int config_parse_n_autovts(
 454                 const char *unit,
 455                 const char *filename,
 456                 unsigned line,
 457                 const char *section,
 458                 unsigned section_line,
 459                 const char *lvalue,
 460                 int ltype,
 461                 const char *rvalue,
 462                 void *data,
 463                 void *userdata) {
 464
 465         unsigned *n = data;
 466         unsigned o;
 467         int r;
 468
 469         assert(filename);
 470         assert(lvalue);
 471         assert(rvalue);
 472         assert(data);
 473
 474         r = safe_atou(rvalue, &o);
 475         if (r < 0) {
 476                 log_syntax(unit, LOG_WARNING, filename, line, r,
 477                            "Failed to parse number of autovts, ignoring: %s", rvalue);
 478                 return 0;
 479         }
 480
 481         if (o > 15) {
 482                 log_syntax(unit, LOG_WARNING, filename, line, 0,
 483                            "A maximum of 15 autovts are supported, ignoring: %s", rvalue);
 484                 return 0;
 485         }
 486
 487         *n = o;
 488         return 0;
 489 }
 490
 491 static int vt_is_busy(unsigned vtnr) {
 492         struct vt_stat vt_stat;
 493         int r;
 494         _cleanup_close_ int fd = -1;
 495
 496         assert(vtnr >= 1);
 497
 498         /* VT_GETSTATE "cannot return state for more than 16 VTs, since v_state is short" */
 499         assert(vtnr <= 15);
 500
 501         /* We explicitly open /dev/tty1 here instead of /dev/tty0. If
 502          * we'd open the latter we'd open the foreground tty which
 503          * hence would be unconditionally busy. By opening /dev/tty1
 504          * we avoid this. Since tty1 is special and needs to be an
 505          * explicitly loaded getty or DM this is safe. */
 506
 507         fd = open_terminal("/dev/tty1", O_RDWR|O_NOCTTY|O_CLOEXEC);
 508         if (fd < 0)
 509                 return -errno;
 510
 511         if (ioctl(fd, VT_GETSTATE, &vt_stat) < 0)
 512                 r = -errno;
 513         else
 514                 r = !!(vt_stat.v_state & (1 << vtnr));
 515
 516         return r;
 517 }
 518
 519 int manager_spawn_autovt(Manager *m, unsigned vtnr) {
 520         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 521         char name[sizeof("autovt@tty.service") + DECIMAL_STR_MAX(unsigned)];
 522         int r;
 523
 524         assert(m);
 525         assert(vtnr >= 1);
 526
 527         if (vtnr > m->n_autovts &&
 528             vtnr != m->reserve_vt)
 529                 return 0;
 530
 531         if (vtnr != m->reserve_vt) {
 532                 /* If this is the reserved TTY, we'll start the getty
 533                  * on it in any case, but otherwise only if it is not
 534                  * busy. */
 535
 536                 r = vt_is_busy(vtnr);
 537                 if (r < 0)
 538                         return r;
 539                 else if (r > 0)
 540                         return -EBUSY;
 541         }
 542
 543         xsprintf(name, "autovt@tty%u.service", vtnr);
 544         r = sd_bus_call_method(
 545                         m->bus,
 546                         "org.freedesktop.systemd1",
 547                         "/org/freedesktop/systemd1",
 548                         "org.freedesktop.systemd1.Manager",
 549                         "StartUnit",
 550                         &error,
 551                         NULL,
 552                         "ss", name, "fail");
 553         if (r < 0)
 554                 return log_error_errno(r, "Failed to start %s: %s", name, bus_error_message(&error, r));
 555
 556         return 0;
 557 }
 558
 559 bool manager_is_lid_closed(Manager *m) {
 560         Button *b;
 561
 562         HASHMAP_FOREACH(b, m->buttons)
 563                 if (b->lid_closed)
 564                         return true;
 565
 566         return false;
 567 }
 568
 569 static bool manager_is_docked(Manager *m) {
 570         Button *b;
 571
 572         HASHMAP_FOREACH(b, m->buttons)
 573                 if (b->docked)
 574                         return true;
 575
 576         return false;
 577 }
 578
 579 static int manager_count_external_displays(Manager *m) {
 580         _cleanup_(sd_device_enumerator_unrefp) sd_device_enumerator *e = NULL;
 581         sd_device *d;
 582         int r, n = 0;
 583
 584         r = sd_device_enumerator_new(&e);
 585         if (r < 0)
 586                 return r;
 587
 588         r = sd_device_enumerator_allow_uninitialized(e);
 589         if (r < 0)
 590                 return r;
 591
 592         r = sd_device_enumerator_add_match_subsystem(e, "drm", true);
 593         if (r < 0)
 594                 return r;
 595
 596         FOREACH_DEVICE(e, d) {
 597                 const char *status, *enabled, *dash, *nn, *subsys;
 598                 sd_device *p;
 599
 600                 if (sd_device_get_parent(d, &p) < 0)
 601                         continue;
 602
 603                 /* If the parent shares the same subsystem as the
 604                  * device we are looking at then it is a connector,
 605                  * which is what we are interested in. */
 606                 if (sd_device_get_subsystem(p, &subsys) < 0 || !streq(subsys, "drm"))
 607                         continue;
 608
 609                 if (sd_device_get_sysname(d, &nn) < 0)
 610                         continue;
 611
 612                 /* Ignore internal displays: the type is encoded in the sysfs name, as the second dash
 613                  * separated item (the first is the card name, the last the connector number). We implement a
 614                  * deny list of external displays here, rather than an allow list of internal ones, to ensure
 615                  * we don't block suspends too eagerly. */
 616                 dash = strchr(nn, '-');
 617                 if (!dash)
 618                         continue;
 619
 620                 dash++;
 621                 if (!STARTSWITH_SET(dash,
 622                                     "VGA-", "DVI-I-", "DVI-D-", "DVI-A-"
 623                                     "Composite-", "SVIDEO-", "Component-",
 624                                     "DIN-", "DP-", "HDMI-A-", "HDMI-B-", "TV-"))
 625                         continue;
 626
 627                 /* Ignore ports that are not enabled */
 628                 if (sd_device_get_sysattr_value(d, "enabled", &enabled) < 0 || !streq(enabled, "enabled"))
 629                         continue;
 630
 631                 /* We count any connector which is not explicitly
 632                  * "disconnected" as connected. */
 633                 if (sd_device_get_sysattr_value(d, "status", &status) < 0 || !streq(status, "disconnected"))
 634                         n++;
 635         }
 636
 637         return n;
 638 }
 639
 640 bool manager_is_docked_or_external_displays(Manager *m) {
 641         int n;
 642
 643         /* If we are docked don't react to lid closing */
 644         if (manager_is_docked(m)) {
 645                 log_debug("System is docked.");
 646                 return true;
 647         }
 648
 649         /* If we have more than one display connected,
 650          * assume that we are docked. */
 651         n = manager_count_external_displays(m);
 652         if (n < 0)
 653                 log_warning_errno(n, "Display counting failed: %m");
 654         else if (n >= 1) {
 655                 log_debug("External (%i) displays connected.", n);
 656                 return true;
 657         }
 658
 659         return false;
 660 }
 661
 662 bool manager_is_on_external_power(void) {
 663         int r;
 664
 665         /* For now we only check for AC power, but 'external power' can apply to anything that isn't an internal
 666          * battery */
 667         r = on_ac_power();
 668         if (r < 0)
 669                 log_warning_errno(r, "Failed to read AC power status: %m");
 670
 671         return r != 0; /* Treat failure as 'on AC' */
 672 }
 673
 674 bool manager_all_buttons_ignored(Manager *m) {
 675         assert(m);
 676
 677         if (m->handle_power_key != HANDLE_IGNORE)
 678                 return false;
 679         if (m->handle_power_key_long_press != HANDLE_IGNORE)
 680                 return false;
 681         if (m->handle_suspend_key != HANDLE_IGNORE)
 682                 return false;
 683         if (m->handle_suspend_key_long_press != HANDLE_IGNORE)
 684                 return false;
 685         if (m->handle_hibernate_key != HANDLE_IGNORE)
 686                 return false;
 687         if (m->handle_hibernate_key_long_press != HANDLE_IGNORE)
 688                 return false;
 689         if (m->handle_reboot_key != HANDLE_IGNORE)
 690                 return false;
 691         if (m->handle_reboot_key_long_press != HANDLE_IGNORE)
 692                 return false;
 693         if (m->handle_lid_switch != HANDLE_IGNORE)
 694                 return false;
 695         if (!IN_SET(m->handle_lid_switch_ep, _HANDLE_ACTION_INVALID, HANDLE_IGNORE))
 696                 return false;
 697         if (m->handle_lid_switch_docked != HANDLE_IGNORE)
 698                 return false;
 699
 700         return true;
 701 }
 702
 703 int manager_read_utmp(Manager *m) {
 704 #if ENABLE_UTMP
 705         int r;
 706         _cleanup_(utxent_cleanup) bool utmpx = false;
 707
 708         assert(m);
 709
 710         if (utmpxname(_PATH_UTMPX) < 0)
 711                 return log_error_errno(errno, "Failed to set utmp path to " _PATH_UTMPX ": %m");
 712
 713         utmpx = utxent_start();
 714
 715         for (;;) {
 716                 _cleanup_free_ char *t = NULL;
 717                 struct utmpx *u;
 718                 const char *c;
 719                 Session *s;
 720
 721                 errno = 0;
 722                 u = getutxent();
 723                 if (!u) {
 724                         if (errno != 0)
 725                                 log_warning_errno(errno, "Failed to read " _PATH_UTMPX ", ignoring: %m");
 726                         return 0;
 727                 }
 728
 729                 if (u->ut_type != USER_PROCESS)
 730                         continue;
 731
 732                 if (!pid_is_valid(u->ut_pid))
 733                         continue;
 734
 735                 t = strndup(u->ut_line, sizeof(u->ut_line));
 736                 if (!t)
 737                         return log_oom();
 738
 739                 c = path_startswith(t, "/dev/");
 740                 if (c) {
 741                         r = free_and_strdup(&t, c);
 742                         if (r < 0)
 743                                 return log_oom();
 744                 }
 745
 746                 if (isempty(t))
 747                         continue;
 748
 749                 s = hashmap_get(m->sessions_by_leader, PID_TO_PTR(u->ut_pid));
 750                 if (!s)
 751                         continue;
 752
 753                 if (s->tty_validity == TTY_FROM_UTMP && !streq_ptr(s->tty, t)) {
 754                         /* This may happen on multiplexed SSH connection (i.e. 'SSH connection sharing'). In
 755                          * this case PAM and utmp sessions don't match. In such a case let's invalidate the TTY
 756                          * information and never acquire it again. */
 757
 758                         s->tty = mfree(s->tty);
 759                         s->tty_validity = TTY_UTMP_INCONSISTENT;
 760                         log_debug("Session '%s' has inconsistent TTY information, dropping TTY information.", s->id);
 761                         continue;
 762                 }
 763
 764                 /* Never override what we figured out once */
 765                 if (s->tty || s->tty_validity >= 0)
 766                         continue;
 767
 768                 s->tty = TAKE_PTR(t);
 769                 s->tty_validity = TTY_FROM_UTMP;
 770                 log_debug("Acquired TTY information '%s' from utmp for session '%s'.", s->tty, s->id);
 771         }
 772
 773 #else
 774         return 0;
 775 #endif
 776 }
 777
 778 #if ENABLE_UTMP
 779 static int manager_dispatch_utmp(sd_event_source *s, const struct inotify_event *event, void *userdata) {
 780         Manager *m = userdata;
 781
 782         assert(m);
 783
 784         /* If there's indication the file itself might have been removed or became otherwise unavailable, then let's
 785          * reestablish the watch on whatever there's now. */
 786         if ((event->mask & (IN_ATTRIB|IN_DELETE_SELF|IN_MOVE_SELF|IN_Q_OVERFLOW|IN_UNMOUNT)) != 0)
 787                 manager_connect_utmp(m);
 788
 789         (void) manager_read_utmp(m);
 790         return 0;
 791 }
 792 #endif
 793
 794 void manager_connect_utmp(Manager *m) {
 795 #if ENABLE_UTMP
 796         sd_event_source *s = NULL;
 797         int r;
 798
 799         assert(m);
 800
 801         /* Watch utmp for changes via inotify. We do this to deal with tools such as ssh, which will register the PAM
 802          * session early, and acquire a TTY only much later for the connection. Thus during PAM the TTY won't be known
 803          * yet. ssh will register itself with utmp when it finally acquired the TTY. Hence, let's make use of this, and
 804          * watch utmp for the TTY asynchronously. We use the PAM session's leader PID as key, to find the right entry.
 805          *
 806          * Yes, relying on utmp is pretty ugly, but it's good enough for informational purposes, as well as idle
 807          * detection (which, for tty sessions, relies on the TTY used) */
 808
 809         r = sd_event_add_inotify(m->event, &s, _PATH_UTMPX, IN_MODIFY|IN_MOVE_SELF|IN_DELETE_SELF|IN_ATTRIB, manager_dispatch_utmp, m);
 810         if (r < 0)
 811                 log_full_errno(r == -ENOENT ? LOG_DEBUG: LOG_WARNING, r, "Failed to create inotify watch on " _PATH_UTMPX ", ignoring: %m");
 812         else {
 813                 r = sd_event_source_set_priority(s, SD_EVENT_PRIORITY_IDLE);
 814                 if (r < 0)
 815                         log_warning_errno(r, "Failed to adjust utmp event source priority, ignoring: %m");
 816
 817                 (void) sd_event_source_set_description(s, "utmp");
 818         }
 819
 820         sd_event_source_unref(m->utmp_event_source);
 821         m->utmp_event_source = s;
 822 #endif
 823 }
 824
 825 void manager_reconnect_utmp(Manager *m) {
 826 #if ENABLE_UTMP
 827         assert(m);
 828
 829         if (m->utmp_event_source)
 830                 return;
 831
 832         manager_connect_utmp(m);
 833 #endif
 834 }
 835
 836 int manager_read_efi_boot_loader_entries(Manager *m) {
 837 #if ENABLE_EFI
 838         int r;
 839
 840         assert(m);
 841         if (m->efi_boot_loader_entries_set)
 842                 return 0;
 843
 844         r = efi_loader_get_entries(&m->efi_boot_loader_entries);
 845         if (r == -ENOENT || ERRNO_IS_NOT_SUPPORTED(r)) {
 846                 log_debug_errno(r, "Boot loader reported no entries.");
 847                 m->efi_boot_loader_entries_set = true;
 848                 return 0;
 849         }
 850         if (r < 0)
 851                 return log_error_errno(r, "Failed to determine entries reported by boot loader: %m");
 852
 853         m->efi_boot_loader_entries_set = true;
 854         return 1;
 855 #else
 856         return 0;
 857 #endif
 858 }