src/login/logind-core.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright 2011 Lennart Poettering
   6 ***/
   7
   8 #include <fcntl.h>
   9 #include <pwd.h>
  10 #include <sys/ioctl.h>
  11 #include <sys/types.h>
  12 #include <linux/vt.h>
  13
  14 #include "alloc-util.h"
  15 #include "bus-error.h"
  16 #include "bus-util.h"
  17 #include "cgroup-util.h"
  18 #include "fd-util.h"
  19 #include "logind.h"
  20 #include "parse-util.h"
  21 #include "process-util.h"
  22 #include "strv.h"
  23 #include "terminal-util.h"
  24 #include "udev-util.h"
  25 #include "user-util.h"
  26
  27 int manager_add_device(Manager *m, const char *sysfs, bool master, Device **_device) {
  28         Device *d;
  29
  30         assert(m);
  31         assert(sysfs);
  32
  33         d = hashmap_get(m->devices, sysfs);
  34         if (d)
  35                 /* we support adding master-flags, but not removing them */
  36                 d->master = d->master || master;
  37         else {
  38                 d = device_new(m, sysfs, master);
  39                 if (!d)
  40                         return -ENOMEM;
  41         }
  42
  43         if (_device)
  44                 *_device = d;
  45
  46         return 0;
  47 }
  48
  49 int manager_add_seat(Manager *m, const char *id, Seat **_seat) {
  50         Seat *s;
  51
  52         assert(m);
  53         assert(id);
  54
  55         s = hashmap_get(m->seats, id);
  56         if (!s) {
  57                 s = seat_new(m, id);
  58                 if (!s)
  59                         return -ENOMEM;
  60         }
  61
  62         if (_seat)
  63                 *_seat = s;
  64
  65         return 0;
  66 }
  67
  68 int manager_add_session(Manager *m, const char *id, Session **_session) {
  69         Session *s;
  70
  71         assert(m);
  72         assert(id);
  73
  74         s = hashmap_get(m->sessions, id);
  75         if (!s) {
  76                 s = session_new(m, id);
  77                 if (!s)
  78                         return -ENOMEM;
  79         }
  80
  81         if (_session)
  82                 *_session = s;
  83
  84         return 0;
  85 }
  86
  87 int manager_add_user(Manager *m, uid_t uid, gid_t gid, const char *name, User **_user) {
  88         User *u;
  89         int r;
  90
  91         assert(m);
  92         assert(name);
  93
  94         u = hashmap_get(m->users, UID_TO_PTR(uid));
  95         if (!u) {
  96                 r = user_new(&u, m, uid, gid, name);
  97                 if (r < 0)
  98                         return r;
  99         }
 100
 101         if (_user)
 102                 *_user = u;
 103
 104         return 0;
 105 }
 106
 107 int manager_add_user_by_name(Manager *m, const char *name, User **_user) {
 108         uid_t uid;
 109         gid_t gid;
 110         int r;
 111
 112         assert(m);
 113         assert(name);
 114
 115         r = get_user_creds(&name, &uid, &gid, NULL, NULL);
 116         if (r < 0)
 117                 return r;
 118
 119         return manager_add_user(m, uid, gid, name, _user);
 120 }
 121
 122 int manager_add_user_by_uid(Manager *m, uid_t uid, User **_user) {
 123         struct passwd *p;
 124
 125         assert(m);
 126
 127         errno = 0;
 128         p = getpwuid(uid);
 129         if (!p)
 130                 return errno > 0 ? -errno : -ENOENT;
 131
 132         return manager_add_user(m, uid, p->pw_gid, p->pw_name, _user);
 133 }
 134
 135 int manager_add_inhibitor(Manager *m, const char* id, Inhibitor **_inhibitor) {
 136         Inhibitor *i;
 137
 138         assert(m);
 139         assert(id);
 140
 141         i = hashmap_get(m->inhibitors, id);
 142         if (i) {
 143                 if (_inhibitor)
 144                         *_inhibitor = i;
 145
 146                 return 0;
 147         }
 148
 149         i = inhibitor_new(m, id);
 150         if (!i)
 151                 return -ENOMEM;
 152
 153         if (_inhibitor)
 154                 *_inhibitor = i;
 155
 156         return 0;
 157 }
 158
 159 int manager_add_button(Manager *m, const char *name, Button **_button) {
 160         Button *b;
 161
 162         assert(m);
 163         assert(name);
 164
 165         b = hashmap_get(m->buttons, name);
 166         if (!b) {
 167                 b = button_new(m, name);
 168                 if (!b)
 169                         return -ENOMEM;
 170         }
 171
 172         if (_button)
 173                 *_button = b;
 174
 175         return 0;
 176 }
 177
 178 int manager_process_seat_device(Manager *m, struct udev_device *d) {
 179         Device *device;
 180         int r;
 181
 182         assert(m);
 183
 184         if (streq_ptr(udev_device_get_action(d), "remove")) {
 185
 186                 device = hashmap_get(m->devices, udev_device_get_syspath(d));
 187                 if (!device)
 188                         return 0;
 189
 190                 seat_add_to_gc_queue(device->seat);
 191                 device_free(device);
 192
 193         } else {
 194                 const char *sn;
 195                 Seat *seat = NULL;
 196                 bool master;
 197
 198                 sn = udev_device_get_property_value(d, "ID_SEAT");
 199                 if (isempty(sn))
 200                         sn = "seat0";
 201
 202                 if (!seat_name_is_valid(sn)) {
 203                         log_warning("Device with invalid seat name %s found, ignoring.", sn);
 204                         return 0;
 205                 }
 206
 207                 seat = hashmap_get(m->seats, sn);
 208                 master = udev_device_has_tag(d, "master-of-seat");
 209
 210                 /* Ignore non-master devices for unknown seats */
 211                 if (!master && !seat)
 212                         return 0;
 213
 214                 r = manager_add_device(m, udev_device_get_syspath(d), master, &device);
 215                 if (r < 0)
 216                         return r;
 217
 218                 if (!seat) {
 219                         r = manager_add_seat(m, sn, &seat);
 220                         if (r < 0) {
 221                                 if (!device->seat)
 222                                         device_free(device);
 223
 224                                 return r;
 225                         }
 226                 }
 227
 228                 device_attach(device, seat);
 229                 seat_start(seat);
 230         }
 231
 232         return 0;
 233 }
 234
 235 int manager_process_button_device(Manager *m, struct udev_device *d) {
 236         Button *b;
 237
 238         int r;
 239
 240         assert(m);
 241
 242         if (streq_ptr(udev_device_get_action(d), "remove")) {
 243
 244                 b = hashmap_get(m->buttons, udev_device_get_sysname(d));
 245                 if (!b)
 246                         return 0;
 247
 248                 button_free(b);
 249
 250         } else {
 251                 const char *sn;
 252
 253                 r = manager_add_button(m, udev_device_get_sysname(d), &b);
 254                 if (r < 0)
 255                         return r;
 256
 257                 sn = udev_device_get_property_value(d, "ID_SEAT");
 258                 if (isempty(sn))
 259                         sn = "seat0";
 260
 261                 button_set_seat(b, sn);
 262
 263                 r = button_open(b);
 264                 if (r < 0) /* event device doesn't have any keys or switches relevant to us? (or any other error
 265                             * opening the device?) let's close the button again. */
 266                         button_free(b);
 267         }
 268
 269         return 0;
 270 }
 271
 272 int manager_get_session_by_pid(Manager *m, pid_t pid, Session **ret) {
 273         _cleanup_free_ char *unit = NULL;
 274         Session *s;
 275         int r;
 276
 277         assert(m);
 278
 279         if (!pid_is_valid(pid))
 280                 return -EINVAL;
 281
 282         r = cg_pid_get_unit(pid, &unit);
 283         if (r < 0)
 284                 goto not_found;
 285
 286         s = hashmap_get(m->session_units, unit);
 287         if (!s)
 288                 goto not_found;
 289
 290         if (ret)
 291                 *ret = s;
 292
 293         return 1;
 294
 295 not_found:
 296         if (ret)
 297                 *ret = NULL;
 298         return 0;
 299 }
 300
 301 int manager_get_user_by_pid(Manager *m, pid_t pid, User **ret) {
 302         _cleanup_free_ char *unit = NULL;
 303         User *u;
 304         int r;
 305
 306         assert(m);
 307
 308         if (!pid_is_valid(pid))
 309                 return -EINVAL;
 310
 311         r = cg_pid_get_slice(pid, &unit);
 312         if (r < 0)
 313                 goto not_found;
 314
 315         u = hashmap_get(m->user_units, unit);
 316         if (!u)
 317                 goto not_found;
 318
 319         if (ret)
 320                 *ret = u;
 321
 322         return 1;
 323
 324 not_found:
 325         if (ret)
 326                 *ret = NULL;
 327
 328         return 0;
 329 }
 330
 331 int manager_get_idle_hint(Manager *m, dual_timestamp *t) {
 332         Session *s;
 333         bool idle_hint;
 334         dual_timestamp ts = DUAL_TIMESTAMP_NULL;
 335         Iterator i;
 336
 337         assert(m);
 338
 339         idle_hint = !manager_is_inhibited(m, INHIBIT_IDLE, INHIBIT_BLOCK, t, false, false, 0, NULL);
 340
 341         HASHMAP_FOREACH(s, m->sessions, i) {
 342                 dual_timestamp k;
 343                 int ih;
 344
 345                 ih = session_get_idle_hint(s, &k);
 346                 if (ih < 0)
 347                         return ih;
 348
 349                 if (!ih) {
 350                         if (!idle_hint) {
 351                                 if (k.monotonic < ts.monotonic)
 352                                         ts = k;
 353                         } else {
 354                                 idle_hint = false;
 355                                 ts = k;
 356                         }
 357                 } else if (idle_hint) {
 358
 359                         if (k.monotonic > ts.monotonic)
 360                                 ts = k;
 361                 }
 362         }
 363
 364         if (t)
 365                 *t = ts;
 366
 367         return idle_hint;
 368 }
 369
 370 bool manager_shall_kill(Manager *m, const char *user) {
 371         assert(m);
 372         assert(user);
 373
 374         if (!m->kill_exclude_users && streq(user, "root"))
 375                 return false;
 376
 377         if (strv_contains(m->kill_exclude_users, user))
 378                 return false;
 379
 380         if (!strv_isempty(m->kill_only_users))
 381                 return strv_contains(m->kill_only_users, user);
 382
 383         return m->kill_user_processes;
 384 }
 385
 386 int config_parse_n_autovts(
 387                 const char *unit,
 388                 const char *filename,
 389                 unsigned line,
 390                 const char *section,
 391                 unsigned section_line,
 392                 const char *lvalue,
 393                 int ltype,
 394                 const char *rvalue,
 395                 void *data,
 396                 void *userdata) {
 397
 398         unsigned *n = data;
 399         unsigned o;
 400         int r;
 401
 402         assert(filename);
 403         assert(lvalue);
 404         assert(rvalue);
 405         assert(data);
 406
 407         r = safe_atou(rvalue, &o);
 408         if (r < 0) {
 409                 log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse number of autovts, ignoring: %s", rvalue);
 410                 return 0;
 411         }
 412
 413         if (o > 15) {
 414                 log_syntax(unit, LOG_ERR, filename, line, r, "A maximum of 15 autovts are supported, ignoring: %s", rvalue);
 415                 return 0;
 416         }
 417
 418         *n = o;
 419         return 0;
 420 }
 421
 422 static int vt_is_busy(unsigned int vtnr) {
 423         struct vt_stat vt_stat;
 424         int r = 0;
 425         _cleanup_close_ int fd;
 426
 427         assert(vtnr >= 1);
 428
 429         /* VT_GETSTATE "cannot return state for more than 16 VTs, since v_state is short" */
 430         assert(vtnr <= 15);
 431
 432         /* We explicitly open /dev/tty1 here instead of /dev/tty0. If
 433          * we'd open the latter we'd open the foreground tty which
 434          * hence would be unconditionally busy. By opening /dev/tty1
 435          * we avoid this. Since tty1 is special and needs to be an
 436          * explicitly loaded getty or DM this is safe. */
 437
 438         fd = open_terminal("/dev/tty1", O_RDWR|O_NOCTTY|O_CLOEXEC);
 439         if (fd < 0)
 440                 return -errno;
 441
 442         if (ioctl(fd, VT_GETSTATE, &vt_stat) < 0)
 443                 r = -errno;
 444         else
 445                 r = !!(vt_stat.v_state & (1 << vtnr));
 446
 447         return r;
 448 }
 449
 450 int manager_spawn_autovt(Manager *m, unsigned int vtnr) {
 451         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 452         char name[sizeof("autovt@tty.service") + DECIMAL_STR_MAX(unsigned int)];
 453         int r;
 454
 455         assert(m);
 456         assert(vtnr >= 1);
 457
 458         if (vtnr > m->n_autovts &&
 459             vtnr != m->reserve_vt)
 460                 return 0;
 461
 462         if (vtnr != m->reserve_vt) {
 463                 /* If this is the reserved TTY, we'll start the getty
 464                  * on it in any case, but otherwise only if it is not
 465                  * busy. */
 466
 467                 r = vt_is_busy(vtnr);
 468                 if (r < 0)
 469                         return r;
 470                 else if (r > 0)
 471                         return -EBUSY;
 472         }
 473
 474         snprintf(name, sizeof(name), "autovt@tty%u.service", vtnr);
 475         r = sd_bus_call_method(
 476                         m->bus,
 477                         "org.freedesktop.systemd1",
 478                         "/org/freedesktop/systemd1",
 479                         "org.freedesktop.systemd1.Manager",
 480                         "StartUnit",
 481                         &error,
 482                         NULL,
 483                         "ss", name, "fail");
 484         if (r < 0)
 485                 log_error("Failed to start %s: %s", name, bus_error_message(&error, r));
 486
 487         return r;
 488 }
 489
 490 static bool manager_is_docked(Manager *m) {
 491         Iterator i;
 492         Button *b;
 493
 494         HASHMAP_FOREACH(b, m->buttons, i)
 495                 if (b->docked)
 496                         return true;
 497
 498         return false;
 499 }
 500
 501 static int manager_count_external_displays(Manager *m) {
 502         _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
 503         struct udev_list_entry *item = NULL, *first = NULL;
 504         int r;
 505         int n = 0;
 506
 507         e = udev_enumerate_new(m->udev);
 508         if (!e)
 509                 return -ENOMEM;
 510
 511         r = udev_enumerate_add_match_subsystem(e, "drm");
 512         if (r < 0)
 513                 return r;
 514
 515         r = udev_enumerate_scan_devices(e);
 516         if (r < 0)
 517                 return r;
 518
 519         first = udev_enumerate_get_list_entry(e);
 520         udev_list_entry_foreach(item, first) {
 521                 _cleanup_udev_device_unref_ struct udev_device *d = NULL;
 522                 struct udev_device *p;
 523                 const char *status, *enabled, *dash, *nn, *i;
 524                 bool external = false;
 525
 526                 d = udev_device_new_from_syspath(m->udev, udev_list_entry_get_name(item));
 527                 if (!d)
 528                         return -ENOMEM;
 529
 530                 p = udev_device_get_parent(d);
 531                 if (!p)
 532                         continue;
 533
 534                 /* If the parent shares the same subsystem as the
 535                  * device we are looking at then it is a connector,
 536                  * which is what we are interested in. */
 537                 if (!streq_ptr(udev_device_get_subsystem(p), "drm"))
 538                         continue;
 539
 540                 nn = udev_device_get_sysname(d);
 541                 if (!nn)
 542                         continue;
 543
 544                 /* Ignore internal displays: the type is encoded in
 545                  * the sysfs name, as the second dash separated item
 546                  * (the first is the card name, the last the connector
 547                  * number). We implement a whitelist of external
 548                  * displays here, rather than a whitelist, to ensure
 549                  * we don't block suspends too eagerly. */
 550                 dash = strchr(nn, '-');
 551                 if (!dash)
 552                         continue;
 553
 554                 dash++;
 555                 FOREACH_STRING(i, "VGA-", "DVI-I-", "DVI-D-", "DVI-A-"
 556                                "Composite-", "SVIDEO-", "Component-",
 557                                "DIN-", "DP-", "HDMI-A-", "HDMI-B-", "TV-") {
 558
 559                         if (startswith(dash, i)) {
 560                                 external = true;
 561                                 break;
 562                         }
 563                 }
 564                 if (!external)
 565                         continue;
 566
 567                 /* Ignore ports that are not enabled */
 568                 enabled = udev_device_get_sysattr_value(d, "enabled");
 569                 if (!enabled)
 570                         continue;
 571                 if (!streq_ptr(enabled, "enabled"))
 572                         continue;
 573
 574                 /* We count any connector which is not explicitly
 575                  * "disconnected" as connected. */
 576                 status = udev_device_get_sysattr_value(d, "status");
 577                 if (!streq_ptr(status, "disconnected"))
 578                         n++;
 579         }
 580
 581         return n;
 582 }
 583
 584 bool manager_is_docked_or_external_displays(Manager *m) {
 585         int n;
 586
 587         /* If we are docked don't react to lid closing */
 588         if (manager_is_docked(m)) {
 589                 log_debug("System is docked.");
 590                 return true;
 591         }
 592
 593         /* If we have more than one display connected,
 594          * assume that we are docked. */
 595         n = manager_count_external_displays(m);
 596         if (n < 0)
 597                 log_warning_errno(n, "Display counting failed: %m");
 598         else if (n >= 1) {
 599                 log_debug("External (%i) displays connected.", n);
 600                 return true;
 601         }
 602
 603         return false;
 604 }
 605
 606 bool manager_is_on_external_power(void) {
 607         int r;
 608
 609         /* For now we only check for AC power, but 'external power' can apply
 610          * to anything that isn't an internal battery */
 611         r = on_ac_power();
 612         if (r < 0)
 613                 log_warning_errno(r, "Failed to read AC power status: %m");
 614         else if (r > 0)
 615                 return true;
 616
 617         return false;
 618 }
 619
 620 bool manager_all_buttons_ignored(Manager *m) {
 621         assert(m);
 622
 623         if (m->handle_power_key != HANDLE_IGNORE)
 624                 return false;
 625         if (m->handle_suspend_key != HANDLE_IGNORE)
 626                 return false;
 627         if (m->handle_hibernate_key != HANDLE_IGNORE)
 628                 return false;
 629         if (m->handle_lid_switch != HANDLE_IGNORE)
 630                 return false;
 631         if (m->handle_lid_switch_ep != _HANDLE_ACTION_INVALID &&
 632             m->handle_lid_switch_ep != HANDLE_IGNORE)
 633                 return false;
 634         if (m->handle_lid_switch_docked != HANDLE_IGNORE)
 635                 return false;
 636
 637         return true;
 638 }