src/login/logind-core.c

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