src/login/logind-user.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <errno.h>
   4 #include <unistd.h>
   5
   6 #include "alloc-util.h"
   7 #include "bus-common-errors.h"
   8 #include "bus-error.h"
   9 #include "bus-locator.h"
  10 #include "bus-util.h"
  11 #include "cgroup-util.h"
  12 #include "clean-ipc.h"
  13 #include "env-file.h"
  14 #include "escape.h"
  15 #include "fd-util.h"
  16 #include "fileio.h"
  17 #include "format-util.h"
  18 #include "fs-util.h"
  19 #include "hashmap.h"
  20 #include "label-util.h"
  21 #include "limits-util.h"
  22 #include "logind-dbus.h"
  23 #include "logind-user-dbus.h"
  24 #include "logind-user.h"
  25 #include "mkdir-label.h"
  26 #include "parse-util.h"
  27 #include "path-util.h"
  28 #include "percent-util.h"
  29 #include "rm-rf.h"
  30 #include "serialize.h"
  31 #include "special.h"
  32 #include "stdio-util.h"
  33 #include "string-table.h"
  34 #include "strv.h"
  35 #include "tmpfile-util.h"
  36 #include "uid-alloc-range.h"
  37 #include "unit-name.h"
  38 #include "user-util.h"
  39
  40 int user_new(User **ret,
  41              Manager *m,
  42              UserRecord *ur) {
  43
  44         _cleanup_(user_freep) User *u = NULL;
  45         char lu[DECIMAL_STR_MAX(uid_t) + 1];
  46         int r;
  47
  48         assert(ret);
  49         assert(m);
  50         assert(ur);
  51
  52         if (!ur->user_name)
  53                 return -EINVAL;
  54
  55         if (!uid_is_valid(ur->uid))
  56                 return -EINVAL;
  57
  58         u = new(User, 1);
  59         if (!u)
  60                 return -ENOMEM;
  61
  62         *u = (User) {
  63                 .manager = m,
  64                 .user_record = user_record_ref(ur),
  65                 .last_session_timestamp = USEC_INFINITY,
  66         };
  67
  68         if (asprintf(&u->state_file, "/run/systemd/users/" UID_FMT, ur->uid) < 0)
  69                 return -ENOMEM;
  70
  71         if (asprintf(&u->runtime_path, "/run/user/" UID_FMT, ur->uid) < 0)
  72                 return -ENOMEM;
  73
  74         xsprintf(lu, UID_FMT, ur->uid);
  75         r = slice_build_subslice(SPECIAL_USER_SLICE, lu, &u->slice);
  76         if (r < 0)
  77                 return r;
  78
  79         r = unit_name_build("user", lu, ".service", &u->service);
  80         if (r < 0)
  81                 return r;
  82
  83         r = unit_name_build("user-runtime-dir", lu, ".service", &u->runtime_dir_service);
  84         if (r < 0)
  85                 return r;
  86
  87         r = hashmap_put(m->users, UID_TO_PTR(ur->uid), u);
  88         if (r < 0)
  89                 return r;
  90
  91         r = hashmap_put(m->user_units, u->slice, u);
  92         if (r < 0)
  93                 return r;
  94
  95         r = hashmap_put(m->user_units, u->service, u);
  96         if (r < 0)
  97                 return r;
  98
  99         r = hashmap_put(m->user_units, u->runtime_dir_service, u);
 100         if (r < 0)
 101                 return r;
 102
 103         *ret = TAKE_PTR(u);
 104         return 0;
 105 }
 106
 107 User *user_free(User *u) {
 108         if (!u)
 109                 return NULL;
 110
 111         if (u->in_gc_queue)
 112                 LIST_REMOVE(gc_queue, u->manager->user_gc_queue, u);
 113
 114         while (u->sessions)
 115                 session_free(u->sessions);
 116
 117         if (u->service)
 118                 hashmap_remove_value(u->manager->user_units, u->service, u);
 119
 120         if (u->runtime_dir_service)
 121                 hashmap_remove_value(u->manager->user_units, u->runtime_dir_service, u);
 122
 123         if (u->slice)
 124                 hashmap_remove_value(u->manager->user_units, u->slice, u);
 125
 126         hashmap_remove_value(u->manager->users, UID_TO_PTR(u->user_record->uid), u);
 127
 128         sd_event_source_unref(u->timer_event_source);
 129
 130         u->service_job = mfree(u->service_job);
 131
 132         u->service = mfree(u->service);
 133         u->runtime_dir_service = mfree(u->runtime_dir_service);
 134         u->slice = mfree(u->slice);
 135         u->runtime_path = mfree(u->runtime_path);
 136         u->state_file = mfree(u->state_file);
 137
 138         user_record_unref(u->user_record);
 139
 140         return mfree(u);
 141 }
 142
 143 static int user_save_internal(User *u) {
 144         _cleanup_(unlink_and_freep) char *temp_path = NULL;
 145         _cleanup_fclose_ FILE *f = NULL;
 146         int r;
 147
 148         assert(u);
 149         assert(u->state_file);
 150
 151         r = mkdir_safe_label("/run/systemd/users", 0755, 0, 0, MKDIR_WARN_MODE);
 152         if (r < 0)
 153                 goto fail;
 154
 155         r = fopen_temporary(u->state_file, &f, &temp_path);
 156         if (r < 0)
 157                 goto fail;
 158
 159         (void) fchmod(fileno(f), 0644);
 160
 161         fprintf(f,
 162                 "# This is private data. Do not parse.\n"
 163                 "NAME=%s\n"
 164                 "STATE=%s\n"         /* friendly user-facing state */
 165                 "STOPPING=%s\n",     /* low-level state */
 166                 u->user_record->user_name,
 167                 user_state_to_string(user_get_state(u)),
 168                 yes_no(u->stopping));
 169
 170         /* LEGACY: no-one reads RUNTIME= anymore, drop it at some point */
 171         if (u->runtime_path)
 172                 fprintf(f, "RUNTIME=%s\n", u->runtime_path);
 173
 174         if (u->service_job)
 175                 fprintf(f, "SERVICE_JOB=%s\n", u->service_job);
 176
 177         if (u->display)
 178                 fprintf(f, "DISPLAY=%s\n", u->display->id);
 179
 180         if (dual_timestamp_is_set(&u->timestamp))
 181                 fprintf(f,
 182                         "REALTIME="USEC_FMT"\n"
 183                         "MONOTONIC="USEC_FMT"\n",
 184                         u->timestamp.realtime,
 185                         u->timestamp.monotonic);
 186
 187         if (u->last_session_timestamp != USEC_INFINITY)
 188                 fprintf(f, "LAST_SESSION_TIMESTAMP=" USEC_FMT "\n",
 189                         u->last_session_timestamp);
 190
 191         if (u->sessions) {
 192                 bool first;
 193
 194                 fputs("SESSIONS=", f);
 195                 first = true;
 196                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 197                         if (first)
 198                                 first = false;
 199                         else
 200                                 fputc(' ', f);
 201
 202                         fputs(i->id, f);
 203                 }
 204
 205                 fputs("\nSEATS=", f);
 206                 first = true;
 207                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 208                         if (!i->seat)
 209                                 continue;
 210
 211                         if (first)
 212                                 first = false;
 213                         else
 214                                 fputc(' ', f);
 215
 216                         fputs(i->seat->id, f);
 217                 }
 218
 219                 fputs("\nACTIVE_SESSIONS=", f);
 220                 first = true;
 221                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 222                         if (!session_is_active(i))
 223                                 continue;
 224
 225                         if (first)
 226                                 first = false;
 227                         else
 228                                 fputc(' ', f);
 229
 230                         fputs(i->id, f);
 231                 }
 232
 233                 fputs("\nONLINE_SESSIONS=", f);
 234                 first = true;
 235                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 236                         if (session_get_state(i) == SESSION_CLOSING)
 237                                 continue;
 238
 239                         if (first)
 240                                 first = false;
 241                         else
 242                                 fputc(' ', f);
 243
 244                         fputs(i->id, f);
 245                 }
 246
 247                 fputs("\nACTIVE_SEATS=", f);
 248                 first = true;
 249                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 250                         if (!session_is_active(i) || !i->seat)
 251                                 continue;
 252
 253                         if (first)
 254                                 first = false;
 255                         else
 256                                 fputc(' ', f);
 257
 258                         fputs(i->seat->id, f);
 259                 }
 260
 261                 fputs("\nONLINE_SEATS=", f);
 262                 first = true;
 263                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 264                         if (session_get_state(i) == SESSION_CLOSING || !i->seat)
 265                                 continue;
 266
 267                         if (first)
 268                                 first = false;
 269                         else
 270                                 fputc(' ', f);
 271
 272                         fputs(i->seat->id, f);
 273                 }
 274                 fputc('\n', f);
 275         }
 276
 277         r = fflush_and_check(f);
 278         if (r < 0)
 279                 goto fail;
 280
 281         if (rename(temp_path, u->state_file) < 0) {
 282                 r = -errno;
 283                 goto fail;
 284         }
 285
 286         temp_path = mfree(temp_path);
 287         return 0;
 288
 289 fail:
 290         (void) unlink(u->state_file);
 291
 292         return log_error_errno(r, "Failed to save user data %s: %m", u->state_file);
 293 }
 294
 295 int user_save(User *u) {
 296         assert(u);
 297
 298         if (!u->started)
 299                 return 0;
 300
 301         return user_save_internal(u);
 302 }
 303
 304 int user_load(User *u) {
 305         _cleanup_free_ char *realtime = NULL, *monotonic = NULL, *stopping = NULL, *last_session_timestamp = NULL;
 306         int r;
 307
 308         assert(u);
 309
 310         r = parse_env_file(NULL, u->state_file,
 311                            "SERVICE_JOB",            &u->service_job,
 312                            "STOPPING",               &stopping,
 313                            "REALTIME",               &realtime,
 314                            "MONOTONIC",              &monotonic,
 315                            "LAST_SESSION_TIMESTAMP", &last_session_timestamp);
 316         if (r == -ENOENT)
 317                 return 0;
 318         if (r < 0)
 319                 return log_error_errno(r, "Failed to read %s: %m", u->state_file);
 320
 321         if (stopping) {
 322                 r = parse_boolean(stopping);
 323                 if (r < 0)
 324                         log_debug_errno(r, "Failed to parse 'STOPPING' boolean: %s", stopping);
 325                 else
 326                         u->stopping = r;
 327         }
 328
 329         if (realtime)
 330                 (void) deserialize_usec(realtime, &u->timestamp.realtime);
 331         if (monotonic)
 332                 (void) deserialize_usec(monotonic, &u->timestamp.monotonic);
 333         if (last_session_timestamp)
 334                 (void) deserialize_usec(last_session_timestamp, &u->last_session_timestamp);
 335
 336         return 0;
 337 }
 338
 339 static void user_start_service(User *u) {
 340         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 341         int r;
 342
 343         assert(u);
 344
 345         /* Start the service containing the "systemd --user" instance (user@.service). Note that we don't explicitly
 346          * start the per-user slice or the systemd-runtime-dir@.service instance, as those are pulled in both by
 347          * user@.service and the session scopes as dependencies. */
 348
 349         u->service_job = mfree(u->service_job);
 350
 351         r = manager_start_unit(u->manager, u->service, &error, &u->service_job);
 352         if (r < 0)
 353                 log_full_errno(sd_bus_error_has_name(&error, BUS_ERROR_UNIT_MASKED) ? LOG_DEBUG : LOG_WARNING, r,
 354                                "Failed to start user service '%s', ignoring: %s", u->service, bus_error_message(&error, r));
 355 }
 356
 357 static int update_slice_callback(sd_bus_message *m, void *userdata, sd_bus_error *ret_error) {
 358         _cleanup_(user_record_unrefp) UserRecord *ur = ASSERT_PTR(userdata);
 359         const sd_bus_error *e;
 360         int r;
 361
 362         assert(m);
 363
 364         e = sd_bus_message_get_error(m);
 365         if (e) {
 366                 r = sd_bus_error_get_errno(e);
 367                 log_warning_errno(r,
 368                                   "Failed to update slice of %s, ignoring: %s",
 369                                   ur->user_name,
 370                                   bus_error_message(e, r));
 371
 372                 return 0;
 373         }
 374
 375         log_debug("Successfully set slice parameters of %s.", ur->user_name);
 376         return 0;
 377 }
 378
 379 static int user_update_slice(User *u) {
 380         _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL;
 381         int r;
 382
 383         assert(u);
 384
 385         if (u->user_record->tasks_max == UINT64_MAX &&
 386             u->user_record->memory_high == UINT64_MAX &&
 387             u->user_record->memory_max == UINT64_MAX &&
 388             u->user_record->cpu_weight == UINT64_MAX &&
 389             u->user_record->io_weight == UINT64_MAX)
 390                 return 0;
 391
 392         r = bus_message_new_method_call(u->manager->bus, &m, bus_systemd_mgr, "SetUnitProperties");
 393         if (r < 0)
 394                 return bus_log_create_error(r);
 395
 396         r = sd_bus_message_append(m, "sb", u->slice, true);
 397         if (r < 0)
 398                 return bus_log_create_error(r);
 399
 400         r = sd_bus_message_open_container(m, 'a', "(sv)");
 401         if (r < 0)
 402                 return bus_log_create_error(r);
 403
 404         const struct {
 405                 const char *name;
 406                 uint64_t value;
 407         } settings[] = {
 408                 { "TasksMax",   u->user_record->tasks_max   },
 409                 { "MemoryMax",  u->user_record->memory_max  },
 410                 { "MemoryHigh", u->user_record->memory_high },
 411                 { "CPUWeight",  u->user_record->cpu_weight  },
 412                 { "IOWeight",   u->user_record->io_weight   },
 413         };
 414
 415         FOREACH_ARRAY(st, settings, ELEMENTSOF(settings)) {
 416                 if (st->value == UINT64_MAX)
 417                         continue;
 418
 419                 r = sd_bus_message_append(m, "(sv)", st->name, "t", st->value);
 420                 if (r < 0)
 421                         return bus_log_create_error(r);
 422         }
 423
 424         r = sd_bus_message_close_container(m);
 425         if (r < 0)
 426                 return bus_log_create_error(r);
 427
 428         r = sd_bus_call_async(u->manager->bus, NULL, m, update_slice_callback, u->user_record, 0);
 429         if (r < 0)
 430                 return log_error_errno(r, "Failed to change user slice properties: %m");
 431
 432         /* Ref the user record pointer, so that the slot keeps it pinned */
 433         user_record_ref(u->user_record);
 434
 435         return 0;
 436 }
 437
 438 int user_start(User *u) {
 439         assert(u);
 440
 441         if (u->started && !u->stopping)
 442                 return 0;
 443
 444         /* If u->stopping is set, the user is marked for removal and service stop-jobs are queued. We have to clear
 445          * that flag before queueing the start-jobs again. If they succeed, the user object can be re-used just fine
 446          * (pid1 takes care of job-ordering and proper restart), but if they fail, we want to force another user_stop()
 447          * so possibly pending units are stopped. */
 448         u->stopping = false;
 449
 450         if (!u->started)
 451                 log_debug("Starting services for new user %s.", u->user_record->user_name);
 452
 453         /* Save the user data so far, because pam_systemd will read the XDG_RUNTIME_DIR out of it while starting up
 454          * systemd --user.  We need to do user_save_internal() because we have not "officially" started yet. */
 455         user_save_internal(u);
 456
 457         /* Set slice parameters */
 458         (void) user_update_slice(u);
 459
 460         /* Start user@UID.service */
 461         user_start_service(u);
 462
 463         if (!u->started) {
 464                 if (!dual_timestamp_is_set(&u->timestamp))
 465                         dual_timestamp_now(&u->timestamp);
 466                 user_send_signal(u, true);
 467                 u->started = true;
 468         }
 469
 470         /* Save new user data */
 471         user_save(u);
 472
 473         return 0;
 474 }
 475
 476 static void user_stop_service(User *u, bool force) {
 477         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 478         int r;
 479
 480         assert(u);
 481         assert(u->service);
 482
 483         /* The reverse of user_start_service(). Note that we only stop user@UID.service here, and let StopWhenUnneeded=
 484          * deal with the slice and the user-runtime-dir@.service instance. */
 485
 486         u->service_job = mfree(u->service_job);
 487
 488         r = manager_stop_unit(u->manager, u->service, force ? "replace" : "fail", &error, &u->service_job);
 489         if (r < 0)
 490                 log_warning_errno(r, "Failed to stop user service '%s', ignoring: %s", u->service, bus_error_message(&error, r));
 491 }
 492
 493 int user_stop(User *u, bool force) {
 494         int r = 0;
 495
 496         assert(u);
 497
 498         /* This is called whenever we begin with tearing down a user record. It's called in two cases: explicit API
 499          * request to do so via the bus (in which case 'force' is true) and automatically due to GC, if there's no
 500          * session left pinning it (in which case 'force' is false). Note that this just initiates tearing down of the
 501          * user, the User object will remain in memory until user_finalize() is called, see below. */
 502
 503         if (!u->started)
 504                 return 0;
 505
 506         if (u->stopping) { /* Stop jobs have already been queued */
 507                 user_save(u);
 508                 return 0;
 509         }
 510
 511         LIST_FOREACH(sessions_by_user, s, u->sessions) {
 512                 int k;
 513
 514                 k = session_stop(s, force);
 515                 if (k < 0)
 516                         r = k;
 517         }
 518
 519         user_stop_service(u, force);
 520
 521         u->stopping = true;
 522
 523         user_save(u);
 524
 525         return r;
 526 }
 527
 528 int user_finalize(User *u) {
 529         int r = 0, k;
 530
 531         assert(u);
 532
 533         /* Called when the user is really ready to be freed, i.e. when all unit stop jobs and suchlike for it are
 534          * done. This is called as a result of an earlier user_done() when all jobs are completed. */
 535
 536         if (u->started)
 537                 log_debug("User %s logged out.", u->user_record->user_name);
 538
 539         LIST_FOREACH(sessions_by_user, s, u->sessions) {
 540                 k = session_finalize(s);
 541                 if (k < 0)
 542                         r = k;
 543         }
 544
 545         /* Clean SysV + POSIX IPC objects, but only if this is not a system user. Background: in many setups cronjobs
 546          * are run in full PAM and thus logind sessions, even if the code run doesn't belong to actual users but to
 547          * system components. Since enable RemoveIPC= globally for all users, we need to be a bit careful with such
 548          * cases, as we shouldn't accidentally remove a system service's IPC objects while it is running, just because
 549          * a cronjob running as the same user just finished. Hence: exclude system users generally from IPC clean-up,
 550          * and do it only for normal users. */
 551         if (u->manager->remove_ipc && !uid_is_system(u->user_record->uid)) {
 552                 k = clean_ipc_by_uid(u->user_record->uid);
 553                 if (k < 0)
 554                         r = k;
 555         }
 556
 557         (void) unlink(u->state_file);
 558         user_add_to_gc_queue(u);
 559
 560         if (u->started) {
 561                 user_send_signal(u, false);
 562                 u->started = false;
 563         }
 564
 565         return r;
 566 }
 567
 568 int user_get_idle_hint(User *u, dual_timestamp *t) {
 569         bool idle_hint = true;
 570         dual_timestamp ts = DUAL_TIMESTAMP_NULL;
 571
 572         assert(u);
 573
 574         LIST_FOREACH(sessions_by_user, s, u->sessions) {
 575                 dual_timestamp k;
 576                 int ih;
 577
 578                 ih = session_get_idle_hint(s, &k);
 579                 if (ih < 0)
 580                         return ih;
 581
 582                 if (!ih) {
 583                         if (!idle_hint) {
 584                                 if (k.monotonic < ts.monotonic)
 585                                         ts = k;
 586                         } else {
 587                                 idle_hint = false;
 588                                 ts = k;
 589                         }
 590                 } else if (idle_hint) {
 591
 592                         if (k.monotonic > ts.monotonic)
 593                                 ts = k;
 594                 }
 595         }
 596
 597         if (t)
 598                 *t = ts;
 599
 600         return idle_hint;
 601 }
 602
 603 int user_check_linger_file(User *u) {
 604         _cleanup_free_ char *cc = NULL;
 605         char *p = NULL;
 606
 607         cc = cescape(u->user_record->user_name);
 608         if (!cc)
 609                 return -ENOMEM;
 610
 611         p = strjoina("/var/lib/systemd/linger/", cc);
 612         if (access(p, F_OK) < 0) {
 613                 if (errno != ENOENT)
 614                         return -errno;
 615
 616                 return false;
 617         }
 618
 619         return true;
 620 }
 621
 622 static bool user_unit_active(User *u) {
 623         int r;
 624
 625         assert(u->service);
 626         assert(u->runtime_dir_service);
 627         assert(u->slice);
 628
 629         FOREACH_STRING(i, u->service, u->runtime_dir_service, u->slice) {
 630                 _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 631
 632                 r = manager_unit_is_active(u->manager, i, &error);
 633                 if (r < 0)
 634                         log_debug_errno(r, "Failed to determine whether unit '%s' is active, ignoring: %s", i, bus_error_message(&error, r));
 635                 if (r != 0)
 636                         return true;
 637         }
 638
 639         return false;
 640 }
 641
 642 static usec_t user_get_stop_delay(User *u) {
 643         assert(u);
 644
 645         if (u->user_record->stop_delay_usec != UINT64_MAX)
 646                 return u->user_record->stop_delay_usec;
 647
 648         if (user_record_removable(u->user_record) > 0)
 649                 return 0; /* For removable users lower the stop delay to zero */
 650
 651         return u->manager->user_stop_delay;
 652 }
 653
 654 bool user_may_gc(User *u, bool drop_not_started) {
 655         int r;
 656
 657         assert(u);
 658
 659         if (drop_not_started && !u->started)
 660                 return true;
 661
 662         if (u->sessions)
 663                 return false;
 664
 665         if (u->last_session_timestamp != USEC_INFINITY) {
 666                 usec_t user_stop_delay;
 667
 668                 /* All sessions have been closed. Let's see if we shall leave the user record around for a bit */
 669
 670                 user_stop_delay = user_get_stop_delay(u);
 671
 672                 if (user_stop_delay == USEC_INFINITY)
 673                         return false; /* Leave it around forever! */
 674                 if (user_stop_delay > 0 &&
 675                     now(CLOCK_MONOTONIC) < usec_add(u->last_session_timestamp, user_stop_delay))
 676                         return false; /* Leave it around for a bit longer. */
 677         }
 678
 679         /* Is this a user that shall stay around forever ("linger")? Before we say "no" to GC'ing for lingering users, let's check
 680          * if any of the three units that we maintain for this user is still around. If none of them is,
 681          * there's no need to keep this user around even if lingering is enabled. */
 682         if (user_check_linger_file(u) > 0 && user_unit_active(u))
 683                 return false;
 684
 685         /* Check if our job is still pending */
 686         if (u->service_job) {
 687                 _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 688
 689                 r = manager_job_is_active(u->manager, u->service_job, &error);
 690                 if (r < 0)
 691                         log_debug_errno(r, "Failed to determine whether job '%s' is pending, ignoring: %s", u->service_job, bus_error_message(&error, r));
 692                 if (r != 0)
 693                         return false;
 694         }
 695
 696         /* Note that we don't care if the three units we manage for each user object are up or not, as we are managing
 697          * their state rather than tracking it. */
 698
 699         return true;
 700 }
 701
 702 void user_add_to_gc_queue(User *u) {
 703         assert(u);
 704
 705         if (u->in_gc_queue)
 706                 return;
 707
 708         LIST_PREPEND(gc_queue, u->manager->user_gc_queue, u);
 709         u->in_gc_queue = true;
 710 }
 711
 712 UserState user_get_state(User *u) {
 713         assert(u);
 714
 715         if (u->stopping)
 716                 return USER_CLOSING;
 717
 718         if (!u->started || u->service_job)
 719                 return USER_OPENING;
 720
 721         if (u->sessions) {
 722                 bool all_closing = true;
 723
 724                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 725                         SessionState state;
 726
 727                         state = session_get_state(i);
 728                         if (state == SESSION_ACTIVE)
 729                                 return USER_ACTIVE;
 730                         if (state != SESSION_CLOSING)
 731                                 all_closing = false;
 732                 }
 733
 734                 return all_closing ? USER_CLOSING : USER_ONLINE;
 735         }
 736
 737         if (user_check_linger_file(u) > 0 && user_unit_active(u))
 738                 return USER_LINGERING;
 739
 740         return USER_CLOSING;
 741 }
 742
 743 int user_kill(User *u, int signo) {
 744         assert(u);
 745
 746         return manager_kill_unit(u->manager, u->slice, KILL_ALL, signo, NULL);
 747 }
 748
 749 static bool elect_display_filter(Session *s) {
 750         /* Return true if the session is a candidate for the user’s ‘primary session’ or ‘display’. */
 751         assert(s);
 752
 753         return IN_SET(s->class, SESSION_USER, SESSION_GREETER) && s->started && !s->stopping;
 754 }
 755
 756 static int elect_display_compare(Session *s1, Session *s2) {
 757         /* Indexed by SessionType. Lower numbers mean more preferred. */
 758         static const int type_ranks[_SESSION_TYPE_MAX] = {
 759                 [SESSION_UNSPECIFIED] = 0,
 760                 [SESSION_TTY] = -2,
 761                 [SESSION_X11] = -3,
 762                 [SESSION_WAYLAND] = -3,
 763                 [SESSION_MIR] = -3,
 764                 [SESSION_WEB] = -1,
 765         };
 766
 767         /* Calculate the partial order relationship between s1 and s2,
 768          * returning < 0 if s1 is preferred as the user’s ‘primary session’,
 769          * 0 if s1 and s2 are equally preferred or incomparable, or > 0 if s2
 770          * is preferred.
 771          *
 772          * s1 or s2 may be NULL. */
 773         if (!s1 && !s2)
 774                 return 0;
 775
 776         if ((s1 == NULL) != (s2 == NULL))
 777                 return (s1 == NULL) - (s2 == NULL);
 778
 779         if (s1->stopping != s2->stopping)
 780                 return s1->stopping - s2->stopping;
 781
 782         if ((s1->class != SESSION_USER) != (s2->class != SESSION_USER))
 783                 return (s1->class != SESSION_USER) - (s2->class != SESSION_USER);
 784
 785         if ((s1->type == _SESSION_TYPE_INVALID) != (s2->type == _SESSION_TYPE_INVALID))
 786                 return (s1->type == _SESSION_TYPE_INVALID) - (s2->type == _SESSION_TYPE_INVALID);
 787
 788         if (s1->type != s2->type)
 789                 return type_ranks[s1->type] - type_ranks[s2->type];
 790
 791         return 0;
 792 }
 793
 794 void user_elect_display(User *u) {
 795         assert(u);
 796
 797         /* This elects a primary session for each user, which we call the "display". We try to keep the assignment
 798          * stable, but we "upgrade" to better choices. */
 799         log_debug("Electing new display for user %s", u->user_record->user_name);
 800
 801         LIST_FOREACH(sessions_by_user, s, u->sessions) {
 802                 if (!elect_display_filter(s)) {
 803                         log_debug("Ignoring session %s", s->id);
 804                         continue;
 805                 }
 806
 807                 if (elect_display_compare(s, u->display) < 0) {
 808                         log_debug("Choosing session %s in preference to %s", s->id, u->display ? u->display->id : "-");
 809                         u->display = s;
 810                 }
 811         }
 812 }
 813
 814 static int user_stop_timeout_callback(sd_event_source *es, uint64_t usec, void *userdata) {
 815         User *u = ASSERT_PTR(userdata);
 816
 817         user_add_to_gc_queue(u);
 818
 819         return 0;
 820 }
 821
 822 void user_update_last_session_timer(User *u) {
 823         usec_t user_stop_delay;
 824         int r;
 825
 826         assert(u);
 827
 828         if (u->sessions) {
 829                 /* There are sessions, turn off the timer */
 830                 u->last_session_timestamp = USEC_INFINITY;
 831                 u->timer_event_source = sd_event_source_unref(u->timer_event_source);
 832                 return;
 833         }
 834
 835         if (u->last_session_timestamp != USEC_INFINITY)
 836                 return; /* Timer already started */
 837
 838         u->last_session_timestamp = now(CLOCK_MONOTONIC);
 839
 840         assert(!u->timer_event_source);
 841
 842         user_stop_delay = user_get_stop_delay(u);
 843         if (!timestamp_is_set(user_stop_delay))
 844                 return;
 845
 846         if (sd_event_get_state(u->manager->event) == SD_EVENT_FINISHED) {
 847                 log_debug("Not allocating user stop timeout, since we are already exiting.");
 848                 return;
 849         }
 850
 851         r = sd_event_add_time(u->manager->event,
 852                               &u->timer_event_source,
 853                               CLOCK_MONOTONIC,
 854                               usec_add(u->last_session_timestamp, user_stop_delay), 0,
 855                               user_stop_timeout_callback, u);
 856         if (r < 0)
 857                 log_warning_errno(r, "Failed to enqueue user stop event source, ignoring: %m");
 858
 859         if (DEBUG_LOGGING)
 860                 log_debug("Last session of user '%s' logged out, terminating user context in %s.",
 861                           u->user_record->user_name,
 862                           FORMAT_TIMESPAN(user_stop_delay, USEC_PER_MSEC));
 863 }
 864
 865 static const char* const user_state_table[_USER_STATE_MAX] = {
 866         [USER_OFFLINE]   = "offline",
 867         [USER_OPENING]   = "opening",
 868         [USER_LINGERING] = "lingering",
 869         [USER_ONLINE]    = "online",
 870         [USER_ACTIVE]    = "active",
 871         [USER_CLOSING]   = "closing"
 872 };
 873
 874 DEFINE_STRING_TABLE_LOOKUP(user_state, UserState);
 875
 876 int config_parse_tmpfs_size(
 877                 const char* unit,
 878                 const char *filename,
 879                 unsigned line,
 880                 const char *section,
 881                 unsigned section_line,
 882                 const char *lvalue,
 883                 int ltype,
 884                 const char *rvalue,
 885                 void *data,
 886                 void *userdata) {
 887
 888         uint64_t *sz = ASSERT_PTR(data);
 889         int r;
 890
 891         assert(filename);
 892         assert(lvalue);
 893         assert(rvalue);
 894
 895         /* First, try to parse as percentage */
 896         r = parse_permyriad(rvalue);
 897         if (r > 0)
 898                 *sz = physical_memory_scale(r, 10000U);
 899         else {
 900                 uint64_t k;
 901
 902                 /* If the passed argument was not a percentage, or out of range, parse as byte size */
 903
 904                 r = parse_size(rvalue, 1024, &k);
 905                 if (r >= 0 && (k <= 0 || (uint64_t) (size_t) k != k))
 906                         r = -ERANGE;
 907                 if (r < 0) {
 908                         log_syntax(unit, LOG_WARNING, filename, line, r, "Failed to parse size value '%s', ignoring: %m", rvalue);
 909                         return 0;
 910                 }
 911
 912                 *sz = PAGE_ALIGN((size_t) k);
 913         }
 914
 915         return 0;
 916 }
 917
 918 int config_parse_compat_user_tasks_max(
 919                 const char *unit,
 920                 const char *filename,
 921                 unsigned line,
 922                 const char *section,
 923                 unsigned section_line,
 924                 const char *lvalue,
 925                 int ltype,
 926                 const char *rvalue,
 927                 void *data,
 928                 void *userdata) {
 929
 930         assert(filename);
 931         assert(lvalue);
 932         assert(rvalue);
 933
 934         log_syntax(unit, LOG_NOTICE, filename, line, 0,
 935                    "Support for option %s= has been removed.",
 936                    lvalue);
 937         log_info("Hint: try creating /etc/systemd/system/user-.slice.d/50-limits.conf with:\n"
 938                  "        [Slice]\n"
 939                  "        TasksMax=%s",
 940                  rvalue);
 941         return 0;
 942 }