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