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         switch (a) {
 200         case ACTION_HALT:
 201                 log_struct(LOG_INFO,
 202                            LOG_MESSAGE("Halt action called."),
 203                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 204                            NULL);
 205                 break;
 206         case ACTION_POWEROFF:
 207                 log_struct(LOG_INFO,
 208                            LOG_MESSAGE("Poweroff action called."),
 209                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 210                            NULL);
 211                 break;
 212         case ACTION_REBOOT:
 213                 log_struct(LOG_INFO,
 214                            LOG_MESSAGE("Reboot action called."),
 215                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 216                            NULL);
 217                 break;
 218         case ACTION_KEXEC:
 219                 log_struct(LOG_INFO,
 220                            LOG_MESSAGE("KExec action called."),
 221                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 222                            NULL);
 223                 break;
 224         case ACTION_SUSPEND:
 225                 log_struct(LOG_INFO,
 226                            LOG_MESSAGE("Suspend action called."),
 227                            LOG_MESSAGE_ID(SD_MESSAGE_SLEEP_START),
 228                            NULL);
 229                 break;
 230         case ACTION_HIBERNATE:
 231                 log_struct(LOG_INFO,
 232                            LOG_MESSAGE("Hibernate action called."),
 233                            LOG_MESSAGE_ID(SD_MESSAGE_SLEEP_START),
 234                            NULL);
 235         case ACTION_HYBRID_SLEEP:
 236                 log_struct(LOG_INFO,
 237                            LOG_MESSAGE("Hybrid-Sleep action called."),
 238                            LOG_MESSAGE_ID(SD_MESSAGE_SLEEP_START),
 239                            NULL);
 240         case ACTION_CANCEL_SHUTDOWN:
 241                 log_struct(LOG_INFO,
 242                            LOG_MESSAGE("Cancel Shutdown called."),
 243                            LOG_MESSAGE_ID(SD_MESSAGE_SHUTDOWN),
 244                            NULL);
 245                 break;
 246         default:
 247                 break;
 248         }
 249 }
 250
 251 static int elogind_reboot(sd_bus *bus, enum elogind_action a) {
 252         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 253         const char *method  = NULL;
 254         int r;
 255         static const char *table[_ACTION_MAX] = {
 256                 [ACTION_REBOOT]          = "The system is going down for reboot NOW!",
 257                 [ACTION_POWEROFF]        = "The system is going down for power-off NOW!"
 258         };
 259
 260         if (!bus)
 261                 return -EIO;
 262
 263         polkit_agent_open_if_enabled();
 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         r = elogind_set_wall_message(bus, table[a]);
 292
 293         if (r < 0) {
 294                 log_warning_errno(r, "Failed to set wall message, ignoring: %s",
 295                                   bus_error_message(&error, r));
 296                 sd_bus_error_free(&error);
 297         }
 298
 299         /* Now call elogind itself to request the operation */
 300         r = sd_bus_call_method(
 301                         bus,
 302                         "org.freedesktop.login1",
 303                         "/org/freedesktop/login1",
 304                         "org.freedesktop.login1.Manager",
 305                         method,
 306                         &error,
 307                         NULL,
 308                         "b",
 309                         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         polkit_agent_open_if_enabled();
 326
 327         switch (a) {
 328
 329         case ACTION_POWEROFF:
 330                 method = "poweroff";
 331                 break;
 332
 333         case ACTION_REBOOT:
 334                 method = "reboot";
 335                 break;
 336
 337         default:
 338                 return -EINVAL;
 339         }
 340
 341         r = elogind_set_wall_message(bus, NULL);
 342
 343         if (r < 0) {
 344                 log_warning_errno(r, "Failed to set wall message, ignoring: %s",
 345                                   bus_error_message(&error, r));
 346                 sd_bus_error_free(&error);
 347         }
 348
 349         r = sd_bus_call_method(
 350                         bus,
 351                         "org.freedesktop.login1",
 352                         "/org/freedesktop/login1",
 353                         "org.freedesktop.login1.Manager",
 354                         "ScheduleShutdown",
 355                         &error,
 356                         NULL,
 357                         "st",
 358                         method,
 359                         arg_when);
 360
 361         if (r < 0)
 362                 log_error("Failed to execute operation: %s", bus_error_message(&error, r));
 363
 364         return r;
 365 }
 366
 367 static int elogind_set_wall_message(sd_bus* bus, const char* msg) {
 368         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 369         _cleanup_free_ char *m = NULL;
 370         int r;
 371
 372         if (strv_extend(&arg_wall, msg) < 0)
 373                 return log_oom();
 374
 375         m = strv_join(arg_wall, " ");
 376         if (!m)
 377                 return log_oom();
 378
 379         r = sd_bus_call_method(
 380                         bus,
 381                         "org.freedesktop.login1",
 382                         "/org/freedesktop/login1",
 383                         "org.freedesktop.login1.Manager",
 384                         "SetWallMessage",
 385                         &error,
 386                         NULL,
 387                         "sb",
 388                         m,
 389                         !arg_no_wall);
 390
 391         if (r < 0)
 392                 return log_warning_errno(r, "Failed to set wall message, ignoring: %s", bus_error_message(&error, r));
 393
 394         return 0;
 395 }
 396
 397 static int parse_shutdown_time_spec(const char *t, usec_t *_u) {
 398         assert(t);
 399         assert(_u);
 400
 401         if (streq(t, "now"))
 402                 *_u = 0;
 403         else if (!strchr(t, ':')) {
 404                 uint64_t u;
 405
 406                 if (safe_atou64(t, &u) < 0)
 407                         return -EINVAL;
 408
 409                 *_u = now(CLOCK_REALTIME) + USEC_PER_MINUTE * u;
 410         } else {
 411                 char *e = NULL;
 412                 long hour, minute;
 413                 struct tm tm = {};
 414                 time_t s;
 415                 usec_t n;
 416
 417                 errno = 0;
 418                 hour = strtol(t, &e, 10);
 419                 if (errno > 0 || *e != ':' || hour < 0 || hour > 23)
 420                         return -EINVAL;
 421
 422                 minute = strtol(e+1, &e, 10);
 423                 if (errno > 0 || *e != 0 || minute < 0 || minute > 59)
 424                         return -EINVAL;
 425
 426                 n = now(CLOCK_REALTIME);
 427                 s = (time_t) (n / USEC_PER_SEC);
 428
 429                 assert_se(localtime_r(&s, &tm));
 430
 431                 tm.tm_hour = (int) hour;
 432                 tm.tm_min = (int) minute;
 433                 tm.tm_sec = 0;
 434
 435                 assert_se(s = mktime(&tm));
 436
 437                 *_u = (usec_t) s * USEC_PER_SEC;
 438
 439                 while (*_u <= n)
 440                         *_u += USEC_PER_DAY;
 441         }
 442
 443         return 0;
 444 }
 445
 446 void polkit_agent_open_if_enabled(void) {
 447
 448         /* Open the polkit agent as a child process if necessary */
 449
 450         if (!arg_ask_password)
 451                 return;
 452
 453         if (arg_transport != BUS_TRANSPORT_LOCAL)
 454                 return;
 455
 456         polkit_agent_open();
 457 }
 458
 459 int start_special(int argc, char *argv[], void *userdata) {
 460         sd_bus *bus = userdata;
 461         enum elogind_action a;
 462         int r;
 463         char** wall = NULL;
 464
 465         assert(argv);
 466
 467         a = verb_to_action(argv[0]);
 468
 469         elogind_log_special(a);
 470
 471         /* Switch to cancel shutdown, if a shutdown action was requested,
 472            and the option to cancel it was set: */
 473         if ( IN_SET(a, ACTION_POWEROFF, ACTION_REBOOT)
 474           && (arg_action == ACTION_CANCEL_SHUTDOWN) )
 475                 return elogind_cancel_shutdown(bus);
 476
 477         r = check_inhibitors(bus, a);
 478         if (r < 0)
 479                 return r;
 480
 481         /* No power off actions in chroot environments */
 482         if ((a == ACTION_POWEROFF ||
 483              a == ACTION_REBOOT) &&
 484             (running_in_chroot() > 0) ) {
 485                 log_info("Running in chroot, ignoring request.");
 486                 return 0;
 487         }
 488
 489         /* Check time arguments */
 490         if ( IN_SET(a, ACTION_POWEROFF, ACTION_REBOOT)
 491           && (argc > 1)
 492           && (arg_action != ACTION_CANCEL_SHUTDOWN) ) {
 493                 r = parse_shutdown_time_spec(argv[1], &arg_when);
 494                 if (r < 0) {
 495                         log_error("Failed to parse time specification: %s", argv[optind]);
 496                         return r;
 497                 }
 498         } else
 499                 arg_when = now(CLOCK_REALTIME) + USEC_PER_MINUTE;
 500
 501         /* The optional user wall message must be set */
 502         if ((argc > 1) && (arg_action == ACTION_CANCEL_SHUTDOWN) )
 503                 /* No time argument for shutdown cancel */
 504                 wall = argv + 1;
 505         else if (argc > 2)
 506                 /* We skip the time argument */
 507                 wall = argv + 2;
 508
 509         if (wall) {
 510                 arg_wall = strv_copy(wall);
 511                 if (!arg_wall)
 512                         return log_oom();
 513         }
 514
 515         /* Perform requested action */
 516         if (IN_SET(a,
 517                    ACTION_POWEROFF,
 518                    ACTION_REBOOT,
 519                    ACTION_SUSPEND,
 520                    ACTION_HIBERNATE,
 521                    ACTION_HYBRID_SLEEP)) {
 522                 if (arg_when > 0)
 523                         return elogind_schedule_shutdown(bus, a);
 524                 else
 525                         return elogind_reboot(bus, a);
 526         }
 527
 528         return -EOPNOTSUPP;
 529 }
 530