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 = sd_bus_call_method(
 180                         bus,
 181                         "org.freedesktop.login1",
 182                         "/org/freedesktop/login1",
 183                         "org.freedesktop.login1.Manager",
 184                         "CancelScheduledShutdown",
 185                         &error,
 186                         NULL, NULL);
 187         if (r < 0)
 188                 return log_warning_errno(r, "Failed to talk to elogind, shutdown hasn't been cancelled: %s", bus_error_message(&error, r));
 189
 190         return 0;
 191 }
 192
 193 void elogind_cleanup(void) {
 194         polkit_agent_close();
 195         strv_free(arg_wall);
 196 }
 197
 198 static void elogind_log_special(enum elogind_action a) {
 199 #ifdef ENABLE_DEBUG_ELOGIND
 200         switch (a) {
 201         case ACTION_HALT:
 202                 log_struct(LOG_INFO,
 203                            LOG_MESSAGE("Halt action called."),
 204                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 205                            NULL);
 206                 break;
 207         case ACTION_POWEROFF:
 208                 log_struct(LOG_INFO,
 209                            LOG_MESSAGE("Poweroff action called."),
 210                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 211                            NULL);
 212                 break;
 213         case ACTION_REBOOT:
 214                 log_struct(LOG_INFO,
 215                            LOG_MESSAGE("Reboot action called."),
 216                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 217                            NULL);
 218                 break;
 219         case ACTION_KEXEC:
 220                 log_struct(LOG_INFO,
 221                            LOG_MESSAGE("KExec action called."),
 222                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 223                            NULL);
 224                 break;
 225         case ACTION_SUSPEND:
 226                 log_struct(LOG_INFO,
 227                            LOG_MESSAGE("Suspend action called."),
 228                            LOG_MESSAGE_ID(SD_MESSAGE_SLEEP_START),
 229                            NULL);
 230                 break;
 231         case ACTION_HIBERNATE:
 232                 log_struct(LOG_INFO,
 233                            LOG_MESSAGE("Hibernate action called."),
 234                            LOG_MESSAGE_ID(SD_MESSAGE_SLEEP_START),
 235                            NULL);
 236         case ACTION_HYBRID_SLEEP:
 237                 log_struct(LOG_INFO,
 238                            LOG_MESSAGE("Hybrid-Sleep action called."),
 239                            LOG_MESSAGE_ID(SD_MESSAGE_SLEEP_START),
 240                            NULL);
 241         case ACTION_CANCEL_SHUTDOWN:
 242                 log_struct(LOG_INFO,
 243                            LOG_MESSAGE("Cancel Shutdown called."),
 244                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 245                            NULL);
 246                 break;
 247         default:
 248                 break;
 249         }
 250 #endif // ENABLE_DEBUG_ELOGIND
 251 }
 252
 253 static int elogind_reboot(sd_bus *bus, enum elogind_action a) {
 254         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 255         const char *method  = NULL;
 256         int r;
 257         static const char *table[_ACTION_MAX] = {
 258                 [ACTION_REBOOT]          = "The system is going down for reboot NOW!",
 259                 [ACTION_POWEROFF]        = "The system is going down for power-off NOW!"
 260         };
 261
 262         if (!bus)
 263                 return -EIO;
 264
 265         switch (a) {
 266
 267         case ACTION_POWEROFF:
 268                 method = "PowerOff";
 269                 break;
 270
 271         case ACTION_REBOOT:
 272                 method = "Reboot";
 273                 break;
 274
 275         case ACTION_SUSPEND:
 276                 method = "Suspend";
 277                 break;
 278
 279         case ACTION_HIBERNATE:
 280                 method = "Hibernate";
 281                 break;
 282
 283         case ACTION_HYBRID_SLEEP:
 284                 method = "HybridSleep";
 285                 break;
 286
 287         default:
 288                 return -EINVAL;
 289         }
 290
 291         polkit_agent_open_if_enabled();
 292         r = elogind_set_wall_message(bus, table[a]);
 293
 294         if (r < 0) {
 295                 log_warning_errno(r, "Failed to set wall message, ignoring: %s",
 296                                   bus_error_message(&error, r));
 297                 sd_bus_error_free(&error);
 298         }
 299
 300         /* Now call elogind itself to request the operation */
 301         r = sd_bus_call_method(
 302                         bus,
 303                         "org.freedesktop.login1",
 304                         "/org/freedesktop/login1",
 305                         "org.freedesktop.login1.Manager",
 306                         method,
 307                         &error,
 308                         NULL,
 309                         "b", arg_ask_password);
 310
 311         if (r < 0)
 312                 log_error("Failed to execute operation: %s", bus_error_message(&error, r));
 313
 314         return r;
 315 }
 316
 317 static int elogind_schedule_shutdown(sd_bus *bus, enum elogind_action a) {
 318         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 319         const char *method  = NULL;
 320         int r;
 321
 322         if (!bus)
 323                 return -EIO;
 324
 325         switch (a) {
 326
 327         case ACTION_POWEROFF:
 328                 method = "poweroff";
 329                 break;
 330
 331         case ACTION_REBOOT:
 332                 method = "reboot";
 333                 break;
 334
 335         default:
 336                 return -EINVAL;
 337         }
 338
 339         r = elogind_set_wall_message(bus, NULL);
 340
 341         if (r < 0) {
 342                 log_warning_errno(r, "Failed to set wall message, ignoring: %s",
 343                                   bus_error_message(&error, r));
 344                 sd_bus_error_free(&error);
 345         }
 346
 347         r = sd_bus_call_method(
 348                         bus,
 349                         "org.freedesktop.login1",
 350                         "/org/freedesktop/login1",
 351                         "org.freedesktop.login1.Manager",
 352                         "ScheduleShutdown",
 353                         &error,
 354                         NULL,
 355                         "st",
 356                         method,
 357                         arg_when);
 358
 359         if (r < 0)
 360                 log_error("Failed to execute operation: %s", bus_error_message(&error, r));
 361
 362         return r;
 363 }
 364
 365 static int elogind_set_wall_message(sd_bus* bus, const char* msg) {
 366         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 367         _cleanup_free_ char *m = NULL;
 368         int r;
 369
 370         if (strv_extend(&arg_wall, msg) < 0)
 371                 return log_oom();
 372
 373         m = strv_join(arg_wall, " ");
 374         if (!m)
 375                 return log_oom();
 376
 377         r = sd_bus_call_method(
 378                         bus,
 379                         "org.freedesktop.login1",
 380                         "/org/freedesktop/login1",
 381                         "org.freedesktop.login1.Manager",
 382                         "SetWallMessage",
 383                         &error,
 384                         NULL,
 385                         "sb",
 386                         m,
 387                         !arg_no_wall);
 388
 389         if (r < 0)
 390                 return log_warning_errno(r, "Failed to set wall message, ignoring: %s", bus_error_message(&error, r));
 391
 392         return 0;
 393 }
 394
 395 static int parse_shutdown_time_spec(const char *t, usec_t *_u) {
 396         assert(t);
 397         assert(_u);
 398
 399         if (streq(t, "now"))
 400                 *_u = 0;
 401         else if (!strchr(t, ':')) {
 402                 uint64_t u;
 403
 404                 if (safe_atou64(t, &u) < 0)
 405                         return -EINVAL;
 406
 407                 *_u = now(CLOCK_REALTIME) + USEC_PER_MINUTE * u;
 408         } else {
 409                 char *e = NULL;
 410                 long hour, minute;
 411                 struct tm tm = {};
 412                 time_t s;
 413                 usec_t n;
 414
 415                 errno = 0;
 416                 hour = strtol(t, &e, 10);
 417                 if (errno > 0 || *e != ':' || hour < 0 || hour > 23)
 418                         return -EINVAL;
 419
 420                 minute = strtol(e+1, &e, 10);
 421                 if (errno > 0 || *e != 0 || minute < 0 || minute > 59)
 422                         return -EINVAL;
 423
 424                 n = now(CLOCK_REALTIME);
 425                 s = (time_t) (n / USEC_PER_SEC);
 426
 427                 assert_se(localtime_r(&s, &tm));
 428
 429                 tm.tm_hour = (int) hour;
 430                 tm.tm_min = (int) minute;
 431                 tm.tm_sec = 0;
 432
 433                 assert_se(s = mktime(&tm));
 434
 435                 *_u = (usec_t) s * USEC_PER_SEC;
 436
 437                 while (*_u <= n)
 438                         *_u += USEC_PER_DAY;
 439         }
 440
 441         return 0;
 442 }
 443
 444 void polkit_agent_open_if_enabled(void) {
 445
 446         /* Open the polkit agent as a child process if necessary */
 447
 448         if (!arg_ask_password)
 449                 return;
 450
 451         if (arg_transport != BUS_TRANSPORT_LOCAL)
 452                 return;
 453
 454         polkit_agent_open();
 455 }
 456
 457 int start_special(int argc, char *argv[], void *userdata) {
 458         sd_bus *bus = userdata;
 459         enum elogind_action a;
 460         int r;
 461         char** wall = NULL;
 462
 463         assert(argv);
 464
 465         a = verb_to_action(argv[0]);
 466
 467         elogind_log_special(a);
 468
 469         /* No power off actions in chroot environments */
 470         if ( IN_SET(a, ACTION_POWEROFF, ACTION_REBOOT)
 471           && (running_in_chroot() > 0) ) {
 472                 log_info("Running in chroot, ignoring request.");
 473                 return 0;
 474         }
 475
 476         /* Check time arguments */
 477         if ( IN_SET(a, ACTION_POWEROFF, ACTION_REBOOT)
 478           && (argc > 1)
 479           && (arg_action != ACTION_CANCEL_SHUTDOWN) ) {
 480                 r = parse_shutdown_time_spec(argv[1], &arg_when);
 481                 if (r < 0) {
 482                         log_error("Failed to parse time specification: %s", argv[optind]);
 483                         return r;
 484                 }
 485         } else
 486                 arg_when = now(CLOCK_REALTIME) + USEC_PER_MINUTE;
 487
 488         /* The optional user wall message must be set */
 489         if ((argc > 1) && (arg_action == ACTION_CANCEL_SHUTDOWN) )
 490                 /* No time argument for shutdown cancel */
 491                 wall = argv + 1;
 492         else if (argc > 2)
 493                 /* We skip the time argument */
 494                 wall = argv + 2;
 495
 496         if (wall) {
 497                 arg_wall = strv_copy(wall);
 498                 if (!arg_wall)
 499                         return log_oom();
 500         }
 501
 502         /* Switch to cancel shutdown, if a shutdown action was requested,
 503            and the option to cancel it was set: */
 504         if ( IN_SET(a, ACTION_POWEROFF, ACTION_REBOOT)
 505           && (arg_action == ACTION_CANCEL_SHUTDOWN) )
 506                 return elogind_cancel_shutdown(bus);
 507
 508         r = check_inhibitors(bus, a);
 509         if (r < 0)
 510                 return r;
 511
 512         /* Perform requested action */
 513         if (IN_SET(a,
 514                    ACTION_POWEROFF,
 515                    ACTION_REBOOT,
 516                    ACTION_SUSPEND,
 517                    ACTION_HIBERNATE,
 518                    ACTION_HYBRID_SLEEP)) {
 519                 if (arg_when > 0)
 520                         return elogind_schedule_shutdown(bus, a);
 521                 else
 522                         return elogind_reboot(bus, a);
 523         }
 524
 525         return -EOPNOTSUPP;
 526 }
 527