src/login/eloginctl.c

   1 /***
   2   This file is part of elogind.
   3
   4   Copyright 2017 Sven Eden
   5
   6   elogind 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   elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20
  21 #include "bus-error.h"
  22 #include "bus-util.h"
  23 #include "eloginctl.h"
  24 #include "logind-action.h"
  25 #include "parse-util.h"
  26 #include "process-util.h"
  27 #include "sd-login.h"
  28 #include "sd-messages.h"
  29 #include "spawn-polkit-agent.h"
  30 #include "string-util.h"
  31 #include "strv.h"
  32 #include "terminal-util.h"
  33 #include "user-util.h"
  34 #include "virt.h"
  35
  36
  37 elogind_action arg_action            = _ACTION_INVALID;
  38 bool           arg_ask_password      = true;
  39 bool           arg_ignore_inhibitors = false;
  40 bool           arg_no_wall           = false;
  41 BusTransport   arg_transport         = BUS_TRANSPORT_LOCAL;
  42 char**         arg_wall              = NULL;
  43 usec_t         arg_when              = 0;
  44
  45 static const struct {
  46         HandleAction action;
  47         const char*  verb;
  48 } action_table[_ACTION_MAX] = {
  49         [ACTION_POWEROFF]     = { HANDLE_POWEROFF,     "poweroff",    },
  50         [ACTION_REBOOT]       = { HANDLE_REBOOT,       "reboot",      },
  51         [ACTION_SUSPEND]      = { HANDLE_SUSPEND,      "suspend",     },
  52         [ACTION_HIBERNATE]    = { HANDLE_HIBERNATE,    "hibernate",   },
  53         [ACTION_HYBRID_SLEEP] = { HANDLE_HYBRID_SLEEP, "hybrid-sleep" },
  54 };
  55
  56 static int elogind_set_wall_message(sd_bus* bus, const char* msg);
  57
  58 static enum elogind_action verb_to_action(const char *verb) {
  59         enum elogind_action i;
  60
  61         for (i = _ACTION_INVALID; i < _ACTION_MAX; i++)
  62                 if (streq_ptr(action_table[i].verb, verb))
  63                         return i;
  64
  65         return _ACTION_INVALID;
  66 }
  67
  68 static int check_inhibitors(sd_bus* bus, enum elogind_action a) {
  69         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
  70         _cleanup_strv_free_ char **sessions = NULL;
  71         const char *what, *who, *why, *mode;
  72         uint32_t uid, pid;
  73         unsigned c = 0;
  74         char **s;
  75         int r;
  76
  77         if (arg_ignore_inhibitors)
  78                 return 0;
  79
  80         if (arg_when > 0)
  81                 return 0;
  82
  83         if (geteuid() == 0)
  84                 return 0;
  85
  86         if (!on_tty())
  87                 return 0;
  88
  89         r = sd_bus_call_method(
  90                         bus,
  91                         "org.freedesktop.login1",
  92                         "/org/freedesktop/login1",
  93                         "org.freedesktop.login1.Manager",
  94                         "ListInhibitors",
  95                         NULL,
  96                         &reply,
  97                         NULL);
  98         if (r < 0)
  99                 /* If logind is not around, then there are no inhibitors... */
 100                 return 0;
 101
 102         r = sd_bus_message_enter_container(reply, SD_BUS_TYPE_ARRAY, "(ssssuu)");
 103         if (r < 0)
 104                 return bus_log_parse_error(r);
 105
 106         while ((r = sd_bus_message_read(reply, "(ssssuu)", &what, &who, &why, &mode, &uid, &pid)) > 0) {
 107                 _cleanup_free_ char *comm = NULL, *user = NULL;
 108                 _cleanup_strv_free_ char **sv = NULL;
 109
 110                 if (!streq(mode, "block"))
 111                         continue;
 112
 113                 sv = strv_split(what, ":");
 114                 if (!sv)
 115                         return log_oom();
 116
 117                 if ((pid_t) pid < 0)
 118                         return log_error_errno(ERANGE, "Bad PID %"PRIu32": %m", pid);
 119
 120                 if (!strv_contains(sv,
 121                                    IN_SET(a,
 122                                           ACTION_HALT,
 123                                           ACTION_POWEROFF,
 124                                           ACTION_REBOOT,
 125                                           ACTION_KEXEC) ? "shutdown" : "sleep"))
 126                         continue;
 127
 128                 get_process_comm(pid, &comm);
 129                 user = uid_to_name(uid);
 130
 131                 log_warning("Operation inhibited by \"%s\" (PID "PID_FMT" \"%s\", user %s), reason is \"%s\".",
 132                             who, (pid_t) pid, strna(comm), strna(user), why);
 133
 134                 c++;
 135         }
 136         if (r < 0)
 137                 return bus_log_parse_error(r);
 138
 139         r = sd_bus_message_exit_container(reply);
 140         if (r < 0)
 141                 return bus_log_parse_error(r);
 142
 143         /* Check for current sessions */
 144         sd_get_sessions(&sessions);
 145         STRV_FOREACH(s, sessions) {
 146                 _cleanup_free_ char *type = NULL, *tty = NULL, *seat = NULL, *user = NULL, *service = NULL, *class = NULL;
 147
 148                 if (sd_session_get_uid(*s, &uid) < 0 || uid == getuid())
 149                         continue;
 150
 151                 if (sd_session_get_class(*s, &class) < 0 || !streq(class, "user"))
 152                         continue;
 153
 154                 if (sd_session_get_type(*s, &type) < 0 || (!streq(type, "x11") && !streq(type, "tty")))
 155                         continue;
 156
 157                 sd_session_get_tty(*s, &tty);
 158                 sd_session_get_seat(*s, &seat);
 159                 sd_session_get_service(*s, &service);
 160                 user = uid_to_name(uid);
 161
 162                 log_warning("User %s is logged in on %s.", strna(user), isempty(tty) ? (isempty(seat) ? strna(service) : seat) : tty);
 163                 c++;
 164         }
 165
 166         if (c <= 0)
 167                 return 0;
 168
 169         log_error("Please retry operation after closing inhibitors and logging out other users.\nAlternatively, ignore inhibitors and users with 'loginctl -i %s'.",
 170                   action_table[a].verb);
 171
 172         return -EPERM;
 173 }
 174
 175 int elogind_cancel_shutdown(sd_bus *bus) {
 176         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 177         int r;
 178
 179         r = elogind_set_wall_message(bus, NULL);
 180
 181         if (r < 0) {
 182                 log_warning_errno(r, "Failed to set wall message, ignoring: %s",
 183                                   bus_error_message(&error, r));
 184                 sd_bus_error_free(&error);
 185         }
 186
 187         r = sd_bus_call_method(
 188                         bus,
 189                         "org.freedesktop.login1",
 190                         "/org/freedesktop/login1",
 191                         "org.freedesktop.login1.Manager",
 192                         "CancelScheduledShutdown",
 193                         &error,
 194                         NULL, NULL);
 195         if (r < 0)
 196                 return log_warning_errno(r, "Failed to talk to elogind, shutdown hasn't been cancelled: %s", bus_error_message(&error, r));
 197
 198         return 0;
 199 }
 200
 201 void elogind_cleanup(void) {
 202         polkit_agent_close();
 203         strv_free(arg_wall);
 204 }
 205
 206 static void elogind_log_special(enum elogind_action a) {
 207 #ifdef ENABLE_DEBUG_ELOGIND
 208         switch (a) {
 209         case ACTION_HALT:
 210                 log_struct(LOG_INFO,
 211                            LOG_MESSAGE("Halt action called."),
 212                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 213                            NULL);
 214                 break;
 215         case ACTION_POWEROFF:
 216                 log_struct(LOG_INFO,
 217                            LOG_MESSAGE("Poweroff action called."),
 218                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 219                            NULL);
 220                 break;
 221         case ACTION_REBOOT:
 222                 log_struct(LOG_INFO,
 223                            LOG_MESSAGE("Reboot action called."),
 224                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 225                            NULL);
 226                 break;
 227         case ACTION_KEXEC:
 228                 log_struct(LOG_INFO,
 229                            LOG_MESSAGE("KExec action called."),
 230                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 231                            NULL);
 232                 break;
 233         case ACTION_SUSPEND:
 234                 log_struct(LOG_INFO,
 235                            LOG_MESSAGE("Suspend action called."),
 236                            LOG_MESSAGE_ID(SD_MESSAGE_SLEEP_START),
 237                            NULL);
 238                 break;
 239         case ACTION_HIBERNATE:
 240                 log_struct(LOG_INFO,
 241                            LOG_MESSAGE("Hibernate action called."),
 242                            LOG_MESSAGE_ID(SD_MESSAGE_SLEEP_START),
 243                            NULL);
 244                 break;
 245         case ACTION_HYBRID_SLEEP:
 246                 log_struct(LOG_INFO,
 247                            LOG_MESSAGE("Hybrid-Sleep action called."),
 248                            LOG_MESSAGE_ID(SD_MESSAGE_SLEEP_START),
 249                            NULL);
 250                 break;
 251         case ACTION_CANCEL_SHUTDOWN:
 252                 log_struct(LOG_INFO,
 253                            LOG_MESSAGE("Cancel Shutdown called."),
 254                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 255                            NULL);
 256                 break;
 257         default:
 258                 break;
 259         }
 260 #endif // ENABLE_DEBUG_ELOGIND
 261 }
 262
 263 static int elogind_reboot(sd_bus *bus, enum elogind_action a) {
 264         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 265         const char *method  = NULL;
 266         int r;
 267         static const char *table[_ACTION_MAX] = {
 268                 [ACTION_REBOOT]          = "The system is going down for reboot NOW!",
 269                 [ACTION_POWEROFF]        = "The system is going down for power-off NOW!"
 270         };
 271
 272         if (!bus)
 273                 return -EIO;
 274
 275         switch (a) {
 276
 277         case ACTION_POWEROFF:
 278                 method = "PowerOff";
 279                 break;
 280
 281         case ACTION_REBOOT:
 282                 method = "Reboot";
 283                 break;
 284
 285         case ACTION_SUSPEND:
 286                 method = "Suspend";
 287                 break;
 288
 289         case ACTION_HIBERNATE:
 290                 method = "Hibernate";
 291                 break;
 292
 293         case ACTION_HYBRID_SLEEP:
 294                 method = "HybridSleep";
 295                 break;
 296
 297         default:
 298                 return -EINVAL;
 299         }
 300
 301         polkit_agent_open_if_enabled();
 302         r = elogind_set_wall_message(bus, table[a]);
 303
 304         if (r < 0) {
 305                 log_warning_errno(r, "Failed to set wall message, ignoring: %s",
 306                                   bus_error_message(&error, r));
 307                 sd_bus_error_free(&error);
 308         }
 309
 310         /* Now call elogind itself to request the operation */
 311         r = sd_bus_call_method(
 312                         bus,
 313                         "org.freedesktop.login1",
 314                         "/org/freedesktop/login1",
 315                         "org.freedesktop.login1.Manager",
 316                         method,
 317                         &error,
 318                         NULL,
 319                         "b", arg_ask_password);
 320
 321         if (r < 0)
 322                 log_error("Failed to execute operation: %s", bus_error_message(&error, r));
 323
 324         return r;
 325 }
 326
 327 static int elogind_schedule_shutdown(sd_bus *bus, enum elogind_action a) {
 328         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 329         const char *method  = NULL;
 330         int r;
 331
 332         if (!bus)
 333                 return -EIO;
 334
 335         switch (a) {
 336
 337         case ACTION_POWEROFF:
 338                 method = "poweroff";
 339                 break;
 340
 341         case ACTION_REBOOT:
 342                 method = "reboot";
 343                 break;
 344
 345         default:
 346                 return -EINVAL;
 347         }
 348
 349         r = elogind_set_wall_message(bus, NULL);
 350
 351         if (r < 0) {
 352                 log_warning_errno(r, "Failed to set wall message, ignoring: %s",
 353                                   bus_error_message(&error, r));
 354                 sd_bus_error_free(&error);
 355         }
 356
 357         r = sd_bus_call_method(
 358                         bus,
 359                         "org.freedesktop.login1",
 360                         "/org/freedesktop/login1",
 361                         "org.freedesktop.login1.Manager",
 362                         "ScheduleShutdown",
 363                         &error,
 364                         NULL,
 365                         "st",
 366                         method,
 367                         arg_when);
 368
 369         if (r < 0)
 370                 log_error("Failed to execute operation: %s", bus_error_message(&error, r));
 371
 372         return r;
 373 }
 374
 375 static int elogind_set_wall_message(sd_bus* bus, const char* msg) {
 376         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 377         _cleanup_free_ char *m = NULL;
 378         int r;
 379
 380         if (strv_extend(&arg_wall, msg) < 0)
 381                 return log_oom();
 382
 383         m = strv_join(arg_wall, " ");
 384         if (!m)
 385                 return log_oom();
 386
 387         r = sd_bus_call_method(
 388                         bus,
 389                         "org.freedesktop.login1",
 390                         "/org/freedesktop/login1",
 391                         "org.freedesktop.login1.Manager",
 392                         "SetWallMessage",
 393                         &error,
 394                         NULL,
 395                         "sb",
 396                         m,
 397                         !arg_no_wall);
 398
 399         if (r < 0)
 400                 return log_warning_errno(r, "Failed to set wall message, ignoring: %s", bus_error_message(&error, r));
 401
 402         return 0;
 403 }
 404
 405 static int parse_shutdown_time_spec(const char *t, usec_t *_u) {
 406         assert(t);
 407         assert(_u);
 408
 409         if (streq(t, "now"))
 410                 *_u = 0;
 411         else if (!strchr(t, ':')) {
 412                 uint64_t u;
 413
 414                 if (safe_atou64(t, &u) < 0)
 415                         return -EINVAL;
 416
 417                 *_u = now(CLOCK_REALTIME) + USEC_PER_MINUTE * u;
 418         } else {
 419                 char *e = NULL;
 420                 long hour, minute;
 421                 struct tm tm = {};
 422                 time_t s;
 423                 usec_t n;
 424
 425                 errno = 0;
 426                 hour = strtol(t, &e, 10);
 427                 if (errno > 0 || *e != ':' || hour < 0 || hour > 23)
 428                         return -EINVAL;
 429
 430                 minute = strtol(e+1, &e, 10);
 431                 if (errno > 0 || *e != 0 || minute < 0 || minute > 59)
 432                         return -EINVAL;
 433
 434                 n = now(CLOCK_REALTIME);
 435                 s = (time_t) (n / USEC_PER_SEC);
 436
 437                 assert_se(localtime_r(&s, &tm));
 438
 439                 tm.tm_hour = (int) hour;
 440                 tm.tm_min = (int) minute;
 441                 tm.tm_sec = 0;
 442
 443                 assert_se(s = mktime(&tm));
 444
 445                 *_u = (usec_t) s * USEC_PER_SEC;
 446
 447                 while (*_u <= n)
 448                         *_u += USEC_PER_DAY;
 449         }
 450
 451         return 0;
 452 }
 453
 454 void polkit_agent_open_if_enabled(void) {
 455
 456         /* Open the polkit agent as a child process if necessary */
 457
 458         if (!arg_ask_password)
 459                 return;
 460
 461         if (arg_transport != BUS_TRANSPORT_LOCAL)
 462                 return;
 463
 464         polkit_agent_open();
 465 }
 466
 467 int start_special(int argc, char *argv[], void *userdata) {
 468         sd_bus *bus = userdata;
 469         enum elogind_action a;
 470         int r;
 471         char** wall = NULL;
 472
 473         assert(argv);
 474
 475         a = verb_to_action(argv[0]);
 476
 477         elogind_log_special(a);
 478
 479         /* For poweroff and reboot, some extra checks are performed: */
 480         if ( IN_SET(a, ACTION_POWEROFF, ACTION_REBOOT) ) {
 481
 482                 /* No power off actions in chroot environments */
 483                 if ( running_in_chroot() > 0 ) {
 484                         log_info("Running in chroot, ignoring request.");
 485                         return 0;
 486                 }
 487
 488                 /* Check time argument */
 489                 if ( (argc > 1) && (ACTION_CANCEL_SHUTDOWN != arg_action)) {
 490                         r = parse_shutdown_time_spec(argv[1], &arg_when);
 491                         if (r < 0) {
 492                                 log_error("Failed to parse time specification: %s", argv[optind]);
 493                                 return r;
 494                         }
 495                 }
 496
 497                 /* The optional user wall message must be set */
 498                 if ( (argc > 1)
 499                   && ( (arg_action == ACTION_CANCEL_SHUTDOWN)
 500                     || (0 == arg_when) ) )
 501                         /* No time argument for shutdown cancel, or no
 502                          * time argument given. */
 503                         wall = argv + 1;
 504                 else if (argc > 2)
 505                         /* We skip the time argument */
 506                         wall = argv + 2;
 507
 508                 if (wall) {
 509                         arg_wall = strv_copy(wall);
 510                         if (!arg_wall)
 511                                 return log_oom();
 512                 }
 513         }
 514
 515         /* Switch to cancel shutdown, if a shutdown action was requested,
 516            and the option to cancel it was set: */
 517         if ( IN_SET(a, ACTION_POWEROFF, ACTION_REBOOT)
 518           && (arg_action == ACTION_CANCEL_SHUTDOWN) )
 519                 return elogind_cancel_shutdown(bus);
 520
 521         r = check_inhibitors(bus, a);
 522         if (r < 0)
 523                 return r;
 524
 525         /* Perform requested action */
 526         if (IN_SET(a,
 527                    ACTION_POWEROFF,
 528                    ACTION_REBOOT,
 529                    ACTION_SUSPEND,
 530                    ACTION_HIBERNATE,
 531                    ACTION_HYBRID_SLEEP)) {
 532                 if (arg_when > 0)
 533                         return elogind_schedule_shutdown(bus, a);
 534                 else
 535                         return elogind_reboot(bus, a);
 536         }
 537
 538         return -EOPNOTSUPP;
 539 }
 540