bus.c 37.1 KB
Newer Older
1 2 3
/* -*- mode: C; c-file-style: "gnu" -*- */
/* bus.c  message bus context object
 *
4
 * Copyright (C) 2003, 2004 Red Hat, Inc.
5
 *
6
 * Licensed under the Academic Free License version 2.1
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include "bus.h"
#include "activation.h"
#include "connection.h"
#include "services.h"
#include "utils.h"
29
#include "policy.h"
30
#include "config-parser.h"
31
#include "signals.h"
32
#include "selinux.h"
33
#include "dir-watch.h"
34 35
#include <dbus/dbus-list.h>
#include <dbus/dbus-hash.h>
36 37 38 39 40
#include <dbus/dbus-internals.h>

struct BusContext
{
  int refcount;
41
  char *config_file;
42
  char *type;
43
  char *address;
44
  char *pidfile;
45
  char *user;
46
  DBusLoop *loop;
47
  DBusList *servers;
48 49 50
  BusConnections *connections;
  BusActivation *activation;
  BusRegistry *registry;
51
  BusPolicy *policy;
52
  BusMatchmaker *matchmaker;
53
  DBusUserDatabase *user_database;
54
  BusLimits limits;
55
  unsigned int fork : 1;
56 57
};

58
static dbus_int32_t server_data_slot = -1;
59 60 61 62 63 64 65 66 67 68 69 70 71 72

typedef struct
{
  BusContext *context;
} BusServerData;

#define BUS_SERVER_DATA(server) (dbus_server_get_data ((server), server_data_slot))

static BusContext*
server_get_context (DBusServer *server)
{
  BusContext *context;
  BusServerData *bd;
  
73
  if (!dbus_server_allocate_data_slot (&server_data_slot))
74 75 76 77
    return NULL;

  bd = BUS_SERVER_DATA (server);
  if (bd == NULL)
78
    {
79
      dbus_server_free_data_slot (&server_data_slot);
80 81
      return NULL;
    }
82 83 84

  context = bd->context;

85
  dbus_server_free_data_slot (&server_data_slot);
86 87 88 89

  return context;
}

90
static dbus_bool_t
91 92 93 94
server_watch_callback (DBusWatch     *watch,
                       unsigned int   condition,
                       void          *data)
{
95 96 97 98 99 100
  /* FIXME this can be done in dbus-mainloop.c
   * if the code in activation.c for the babysitter
   * watch handler is fixed.
   */
  
  return dbus_watch_handle (watch, condition);
101 102
}

103
static dbus_bool_t
104
add_server_watch (DBusWatch  *watch,
105
                  void       *data)
106
{
107 108 109 110 111
  DBusServer *server = data;
  BusContext *context;
  
  context = server_get_context (server);
  
112 113 114
  return _dbus_loop_add_watch (context->loop,
                               watch, server_watch_callback, server,
                               NULL);
115 116 117 118
}

static void
remove_server_watch (DBusWatch  *watch,
119
                     void       *data)
120
{
121 122 123 124 125
  DBusServer *server = data;
  BusContext *context;
  
  context = server_get_context (server);
  
126 127
  _dbus_loop_remove_watch (context->loop,
                           watch, server_watch_callback, server);
128 129
}

130

131 132 133 134
static void
server_timeout_callback (DBusTimeout   *timeout,
                         void          *data)
{
135
  /* can return FALSE on OOM but we just let it fire again later */
136 137 138 139 140
  dbus_timeout_handle (timeout);
}

static dbus_bool_t
add_server_timeout (DBusTimeout *timeout,
141
                    void        *data)
142
{
143 144 145 146 147
  DBusServer *server = data;
  BusContext *context;
  
  context = server_get_context (server);

148 149
  return _dbus_loop_add_timeout (context->loop,
                                 timeout, server_timeout_callback, server, NULL);
150 151 152 153
}

static void
remove_server_timeout (DBusTimeout *timeout,
154
                       void        *data)
155
{
156 157 158 159 160
  DBusServer *server = data;
  BusContext *context;
  
  context = server_get_context (server);
  
161 162
  _dbus_loop_remove_timeout (context->loop,
                             timeout, server_timeout_callback, server);
163 164
}

165 166 167 168 169 170 171 172
static void
new_connection_callback (DBusServer     *server,
                         DBusConnection *new_connection,
                         void           *data)
{
  BusContext *context = data;
  
  if (!bus_connections_setup_connection (context->connections, new_connection))
173 174
    {
      _dbus_verbose ("No memory to setup new connection\n");
175

176 177 178 179 180
      /* if we don't do this, it will get unref'd without
       * being disconnected... kind of strange really
       * that we have to do this, people won't get it right
       * in general.
       */
181
      dbus_connection_close (new_connection);
182
    }
183 184

  dbus_connection_set_max_received_size (new_connection,
185
                                         context->limits.max_incoming_bytes);
186 187

  dbus_connection_set_max_message_size (new_connection,
188
                                        context->limits.max_message_size);
189
  
190
  /* on OOM, we won't have ref'd the connection so it will die. */
191 192
}

193 194 195 196 197 198 199 200
static void
free_server_data (void *data)
{
  BusServerData *bd = data;  
  
  dbus_free (bd);
}

201 202 203
static dbus_bool_t
setup_server (BusContext *context,
              DBusServer *server,
204
              char      **auth_mechanisms,
205
              DBusError  *error)
206
{
207
  BusServerData *bd;
208 209 210 211 212 213 214 215 216 217 218 219

  bd = dbus_new0 (BusServerData, 1);
  if (!dbus_server_set_data (server,
                             server_data_slot,
                             bd, free_server_data))
    {
      dbus_free (bd);
      BUS_SET_OOM (error);
      return FALSE;
    }

  bd->context = context;
220
  
221 222 223 224 225 226
  if (!dbus_server_set_auth_mechanisms (server, (const char**) auth_mechanisms))
    {
      BUS_SET_OOM (error);
      return FALSE;
    }
  
227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250
  dbus_server_set_new_connection_function (server,
                                           new_connection_callback,
                                           context, NULL);
  
  if (!dbus_server_set_watch_functions (server,
                                        add_server_watch,
                                        remove_server_watch,
                                        NULL,
                                        server,
                                        NULL))
    {
      BUS_SET_OOM (error);
      return FALSE;
    }

  if (!dbus_server_set_timeout_functions (server,
                                          add_server_timeout,
                                          remove_server_timeout,
                                          NULL,
                                          server, NULL))
    {
      BUS_SET_OOM (error);
      return FALSE;
    }
251
  
252 253 254
  return TRUE;
}

255 256 257 258 259 260 261
/* This code only gets executed the first time the
   config files are parsed.  It is not executed
   when config files are reloaded.*/
static dbus_bool_t
process_config_first_time_only (BusContext      *context,
				BusConfigParser *parser,
				DBusError       *error)
262
{
263 264
  DBusList *link;
  DBusList **addresses;
265
  const char *user, *pidfile;
266 267 268
  char **auth_mechanisms;
  DBusList **auth_mechanisms_list;
  int len;
269
  dbus_bool_t retval;
270

271
  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
272

273
  retval = FALSE;
274
  auth_mechanisms = NULL;
275 276 277 278 279 280 281 282 283 284 285 286 287 288

  /* Check for an existing pid file. Of course this is a race;
   * we'd have to use fcntl() locks on the pid file to
   * avoid that. But we want to check for the pid file
   * before overwriting any existing sockets, etc.
   */
  pidfile = bus_config_parser_get_pidfile (parser);
  if (pidfile != NULL)
    {
      DBusString u;
      DBusStat stbuf;
      
      _dbus_string_init_const (&u, pidfile);
      
289
      if (_dbus_stat (&u, &stbuf, NULL))
290 291 292 293 294 295 296
	{
	  dbus_set_error (error, DBUS_ERROR_FAILED,
			  "The pid file \"%s\" exists, if the message bus is not running, remove this file",
			  pidfile);
	  goto failed;
	}
    }
297
  
298 299
  /* keep around the pid filename so we can delete it later */
  context->pidfile = _dbus_strdup (pidfile);
300 301 302 303 304 305 306 307 308 309 310 311

  /* Build an array of auth mechanisms */
  
  auth_mechanisms_list = bus_config_parser_get_mechanisms (parser);
  len = _dbus_list_get_length (auth_mechanisms_list);

  if (len > 0)
    {
      int i;

      auth_mechanisms = dbus_new0 (char*, len + 1);
      if (auth_mechanisms == NULL)
312 313 314 315
	{
	  BUS_SET_OOM (error);
	  goto failed;
	}
316 317 318 319 320 321 322
      
      i = 0;
      link = _dbus_list_get_first_link (auth_mechanisms_list);
      while (link != NULL)
        {
          auth_mechanisms[i] = _dbus_strdup (link->data);
          if (auth_mechanisms[i] == NULL)
323 324 325 326
	    {
	      BUS_SET_OOM (error);
	      goto failed;
	    }
327 328 329 330 331 332 333 334 335
          link = _dbus_list_get_next_link (auth_mechanisms_list, link);
        }
    }
  else
    {
      auth_mechanisms = NULL;
    }

  /* Listen on our addresses */
336 337 338 339 340 341 342 343 344 345
  
  addresses = bus_config_parser_get_addresses (parser);  
  
  link = _dbus_list_get_first_link (addresses);
  while (link != NULL)
    {
      DBusServer *server;
      
      server = dbus_server_listen (link->data, error);
      if (server == NULL)
346 347 348 349
	{
	  _DBUS_ASSERT_ERROR_IS_SET (error);
	  goto failed;
	}
350
      else if (!setup_server (context, server, auth_mechanisms, error))
351 352 353 354
	{
	  _DBUS_ASSERT_ERROR_IS_SET (error);
	  goto failed;
	}
355 356 357 358 359 360 361 362 363 364

      if (!_dbus_list_append (&context->servers, server))
        {
          BUS_SET_OOM (error);
          goto failed;
        }          
      
      link = _dbus_list_get_next_link (addresses, link);
    }

365 366
  /* note that type may be NULL */
  context->type = _dbus_strdup (bus_config_parser_get_type (parser));
367 368 369 370 371
  if (bus_config_parser_get_type (parser) != NULL && context->type == NULL)
    {
      BUS_SET_OOM (error);
      goto failed;
    }
372 373 374 375 376 377 378 379 380 381 382 383 384

  user = bus_config_parser_get_user (parser);
  if (user != NULL)
    {
      context->user = _dbus_strdup (user);
      if (context->user == NULL)
	{
	  BUS_SET_OOM (error);
	  goto failed;
	}
    }

  context->fork = bus_config_parser_get_fork (parser);
385
  
386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423
  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
  retval = TRUE;

 failed:
  dbus_free_string_array (auth_mechanisms);
  return retval;
}

/* This code gets executed every time the config files
   are parsed: both during BusContext construction
   and on reloads. */
static dbus_bool_t
process_config_every_time (BusContext      *context,
			   BusConfigParser *parser,
			   dbus_bool_t      is_reload,
			   DBusError       *error)
{
  DBusString full_address;
  DBusList *link;
  
  dbus_bool_t retval;

  _DBUS_ASSERT_ERROR_IS_CLEAR (error);

  retval = FALSE;

  if (!_dbus_string_init (&full_address))
    {
      BUS_SET_OOM (error);
      return FALSE;
    }

  /* get our limits and timeout lengths */
  bus_config_parser_get_limits (parser, &context->limits);

  context->policy = bus_config_parser_steal_policy (parser);
  _dbus_assert (context->policy != NULL);

424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446
  /* We have to build the address backward, so that
   * <listen> later in the config file have priority
   */
  link = _dbus_list_get_last_link (&context->servers);
  while (link != NULL)
    {
      char *addr;
      
      addr = dbus_server_get_address (link->data);
      if (addr == NULL)
        {
          BUS_SET_OOM (error);
          goto failed;
        }

      if (_dbus_string_get_length (&full_address) > 0)
        {
          if (!_dbus_string_append (&full_address, ";"))
            {
              BUS_SET_OOM (error);
              goto failed;
            }
        }
447

448 449 450 451 452 453 454 455 456 457 458
      if (!_dbus_string_append (&full_address, addr))
        {
          BUS_SET_OOM (error);
          goto failed;
        }

      dbus_free (addr);

      link = _dbus_list_get_prev_link (&context->servers, link);
    }

459 460 461
  if (is_reload)
    dbus_free (context->address);

462
  if (!_dbus_string_copy_data (&full_address, &context->address))
463 464 465 466
    {
      BUS_SET_OOM (error);
      goto failed;
    }
467

468 469 470 471 472 473 474 475 476 477 478 479 480 481
  /* Create activation subsystem */
  
  if (is_reload)
    bus_activation_unref (context->activation);
  
  context->activation = bus_activation_new (context, &full_address,
                                            bus_config_parser_get_service_dirs (parser),
                                            error);
  if (context->activation == NULL)
    {
      _DBUS_ASSERT_ERROR_IS_SET (error);
      goto failed;
    }

482
  /* Drop existing conf-dir watches (if applicable) */
483 484 485 486

  if (is_reload)
    bus_drop_all_directory_watches ();

487 488 489 490 491 492 493 494 495
  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
  retval = TRUE;

 failed:
  _dbus_string_free (&full_address);
  return retval;
}

static dbus_bool_t
496
process_config_postinit (BusContext      *context,
497
			 BusConfigParser *parser,
498
			 DBusError       *error)
499
{
500
  DBusHashTable *service_context_table;
501

502 503 504
  service_context_table = bus_config_parser_steal_service_context_table (parser);
  if (!bus_registry_set_service_context_table (context->registry,
					       service_context_table))
505
    {
506 507
      BUS_SET_OOM (error);
      return FALSE;
508 509
    }

510
  _dbus_hash_table_unref (service_context_table);
511 512 513 514 515 516

  /* Watch all conf directories */
  _dbus_list_foreach (bus_config_parser_get_conf_dirs (parser),
		      (DBusForeachFunction) bus_watch_directory,
		      NULL);

517
  return TRUE;
518 519 520 521
}

BusContext*
bus_context_new (const DBusString *config_file,
522
                 ForceForkSetting  force_fork,
523 524 525 526 527
                 int               print_addr_fd,
                 int               print_pid_fd,
                 DBusError        *error)
{
  BusContext *context;
528
  BusConfigParser *parser;
529 530 531
  
  _DBUS_ASSERT_ERROR_IS_CLEAR (error);

532 533 534
  context = NULL;
  parser = NULL;

535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561
  if (!dbus_server_allocate_data_slot (&server_data_slot))
    {
      BUS_SET_OOM (error);
      return NULL;
    }

  context = dbus_new0 (BusContext, 1);
  if (context == NULL)
    {
      BUS_SET_OOM (error);
      goto failed;
    }
  context->refcount = 1;

  if (!_dbus_string_copy_data (config_file, &context->config_file))
    {
      BUS_SET_OOM (error);
      goto failed;
    }

  context->loop = _dbus_loop_new ();
  if (context->loop == NULL)
    {
      BUS_SET_OOM (error);
      goto failed;
    }

562 563 564 565 566 567
  context->registry = bus_registry_new (context);
  if (context->registry == NULL)
    {
      BUS_SET_OOM (error);
      goto failed;
    }
568 569 570 571 572 573 574

  parser = bus_config_load (config_file, TRUE, NULL, error);
  if (parser == NULL)
    {
      _DBUS_ASSERT_ERROR_IS_SET (error);
      goto failed;
    }
575
  
576 577 578 579 580 581
  if (!process_config_first_time_only (context, parser, error))
    {
      _DBUS_ASSERT_ERROR_IS_SET (error);
      goto failed;
    }
  if (!process_config_every_time (context, parser, FALSE, error))
582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599
    {
      _DBUS_ASSERT_ERROR_IS_SET (error);
      goto failed;
    }
  
  /* we need another ref of the server data slot for the context
   * to own
   */
  if (!dbus_server_allocate_data_slot (&server_data_slot))
    _dbus_assert_not_reached ("second ref of server data slot failed");

  context->user_database = _dbus_user_database_new ();
  if (context->user_database == NULL)
    {
      BUS_SET_OOM (error);
      goto failed;
    }
  
600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641
  /* Note that we don't know whether the print_addr_fd is
   * one of the sockets we're using to listen on, or some
   * other random thing. But I think the answer is "don't do
   * that then"
   */
  if (print_addr_fd >= 0)
    {
      DBusString addr;
      const char *a = bus_context_get_address (context);
      int bytes;
      
      _dbus_assert (a != NULL);
      if (!_dbus_string_init (&addr))
        {
          BUS_SET_OOM (error);
          goto failed;
        }
      
      if (!_dbus_string_append (&addr, a) ||
          !_dbus_string_append (&addr, "\n"))
        {
          _dbus_string_free (&addr);
          BUS_SET_OOM (error);
          goto failed;
        }

      bytes = _dbus_string_get_length (&addr);
      if (_dbus_write (print_addr_fd, &addr, 0, bytes) != bytes)
        {
          dbus_set_error (error, DBUS_ERROR_FAILED,
                          "Printing message bus address: %s\n",
                          _dbus_strerror (errno));
          _dbus_string_free (&addr);
          goto failed;
        }

      if (print_addr_fd > 2)
        _dbus_close (print_addr_fd, NULL);

      _dbus_string_free (&addr);
    }
  
642 643 644 645 646 647 648
  context->connections = bus_connections_new (context);
  if (context->connections == NULL)
    {
      BUS_SET_OOM (error);
      goto failed;
    }

649 650 651 652 653 654 655
  context->matchmaker = bus_matchmaker_new ();
  if (context->matchmaker == NULL)
    {
      BUS_SET_OOM (error);
      goto failed;
    }
  
656
  /* Now become a daemon if appropriate */
657
  if ((force_fork != FORK_NEVER && context->fork) || force_fork == FORK_ALWAYS)
658
    {
659 660
      DBusString u;

661 662
      if (context->pidfile)
        _dbus_string_init_const (&u, context->pidfile);
663
      
664 665 666
      if (!_dbus_become_daemon (context->pidfile ? &u : NULL, 
				print_pid_fd,
				error))
667 668 669 670
	{
	  _DBUS_ASSERT_ERROR_IS_SET (error);
	  goto failed;
	}
671
    }
672 673 674
  else
    {
      /* Need to write PID file for ourselves, not for the child process */
675
      if (context->pidfile != NULL)
676 677 678
        {
          DBusString u;

679
          _dbus_string_init_const (&u, context->pidfile);
680 681
          
          if (!_dbus_write_pid_file (&u, _dbus_getpid (), error))
682 683 684 685
	    {
	      _DBUS_ASSERT_ERROR_IS_SET (error);
	      goto failed;
	    }
686 687
        }
    }
688

689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723
  /* Write PID if requested */
  if (print_pid_fd >= 0)
    {
      DBusString pid;
      int bytes;

      if (!_dbus_string_init (&pid))
        {
          BUS_SET_OOM (error);
          goto failed;
        }
      
      if (!_dbus_string_append_int (&pid, _dbus_getpid ()) ||
          !_dbus_string_append (&pid, "\n"))
        {
          _dbus_string_free (&pid);
          BUS_SET_OOM (error);
          goto failed;
        }

      bytes = _dbus_string_get_length (&pid);
      if (_dbus_write (print_pid_fd, &pid, 0, bytes) != bytes)
        {
          dbus_set_error (error, DBUS_ERROR_FAILED,
                          "Printing message bus PID: %s\n",
                          _dbus_strerror (errno));
          _dbus_string_free (&pid);
          goto failed;
        }

      if (print_pid_fd > 2)
        _dbus_close (print_pid_fd, NULL);
      
      _dbus_string_free (&pid);
    }
724 725 726 727 728 729 730 731 732 733 734

  if (!bus_selinux_full_init ())
    {
      _dbus_warn ("SELinux initialization failed\n");
    }

  if (!process_config_postinit (context, parser, error))
    {
      _DBUS_ASSERT_ERROR_IS_SET (error);
      goto failed;
    }
735

736
  if (parser != NULL)
737 738 739 740
    {
      bus_config_parser_unref (parser);
      parser = NULL;
    }
741
  
742 743 744
  /* Here we change our credentials if required,
   * as soon as we've set up our sockets and pidfile
   */
745
  if (context->user != NULL)
746 747 748 749
    {
      DBusCredentials creds;
      DBusString u;

750
      _dbus_string_init_const (&u, context->user);
751 752 753 754 755 756 757

      if (!_dbus_credentials_from_username (&u, &creds) ||
          creds.uid < 0 ||
          creds.gid < 0)
        {
          dbus_set_error (error, DBUS_ERROR_FAILED,
                          "Could not get UID and GID for username \"%s\"",
758
                          context->user);
759 760 761 762
          goto failed;
        }
      
      if (!_dbus_change_identity (creds.uid, creds.gid, error))
763 764 765 766
	{
	  _DBUS_ASSERT_ERROR_IS_SET (error);
	  goto failed;
	}
767
    }
768
  
769
  dbus_server_free_data_slot (&server_data_slot);
770 771 772
  
  return context;
  
773
 failed:  
774 775
  if (parser != NULL)
    bus_config_parser_unref (parser);
776 777 778
  if (context != NULL)
    bus_context_unref (context);

779 780
  if (server_data_slot >= 0)
    dbus_server_free_data_slot (&server_data_slot);
781
  
782 783 784
  return NULL;
}

785 786 787 788
dbus_bool_t
bus_context_reload_config (BusContext *context,
			   DBusError  *error)
{
789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817
  BusConfigParser *parser;
  DBusString config_file;
  dbus_bool_t ret;

  ret = FALSE;
  _dbus_string_init_const (&config_file, context->config_file);
  parser = bus_config_load (&config_file, TRUE, NULL, error);
  if (parser == NULL)
    {
      _DBUS_ASSERT_ERROR_IS_SET (error);
      goto failed;
    }
  
  if (!process_config_every_time (context, parser, TRUE, error))
    {
      _DBUS_ASSERT_ERROR_IS_SET (error);
      goto failed;
    }
  if (!process_config_postinit (context, parser, error))
    {
      _DBUS_ASSERT_ERROR_IS_SET (error);
      goto failed;
    }
  ret = TRUE;

 failed:  
  if (parser != NULL)
    bus_config_parser_unref (parser);
  return ret;
818 819
}

820 821 822
static void
shutdown_server (BusContext *context,
                 DBusServer *server)
823
{
824 825
  if (server == NULL ||
      !dbus_server_get_is_connected (server))
826 827
    return;
  
828
  if (!dbus_server_set_watch_functions (server,
829
                                        NULL, NULL, NULL,
830 831 832 833
                                        context,
                                        NULL))
    _dbus_assert_not_reached ("setting watch functions to NULL failed");
  
834
  if (!dbus_server_set_timeout_functions (server,
835
                                          NULL, NULL, NULL,
836 837 838 839
                                          context,
                                          NULL))
    _dbus_assert_not_reached ("setting timeout functions to NULL failed");
  
840 841 842 843 844 845 846 847 848 849 850 851 852 853 854
  dbus_server_disconnect (server);
}

void
bus_context_shutdown (BusContext  *context)
{
  DBusList *link;

  link = _dbus_list_get_first_link (&context->servers);
  while (link != NULL)
    {
      shutdown_server (context, link->data);

      link = _dbus_list_get_next_link (&context->servers, link);
    }
855 856
}

857
BusContext *
858 859 860 861
bus_context_ref (BusContext *context)
{
  _dbus_assert (context->refcount > 0);
  context->refcount += 1;
862 863

  return context;
864 865 866 867 868 869 870 871 872 873
}

void
bus_context_unref (BusContext *context)
{
  _dbus_assert (context->refcount > 0);
  context->refcount -= 1;

  if (context->refcount == 0)
    {
874 875
      DBusList *link;
      
876 877
      _dbus_verbose ("Finalizing bus context %p\n", context);
      
878
      bus_context_shutdown (context);
879 880 881 882 883 884

      if (context->connections)
        {
          bus_connections_unref (context->connections);
          context->connections = NULL;
        }
885
      
886
      if (context->registry)
887 888 889 890 891
        {
          bus_registry_unref (context->registry);
          context->registry = NULL;
        }
      
892
      if (context->activation)
893 894 895 896
        {
          bus_activation_unref (context->activation);
          context->activation = NULL;
        }
897 898 899

      link = _dbus_list_get_first_link (&context->servers);
      while (link != NULL)
900
        {
901 902 903
          dbus_server_unref (link->data);
          
          link = _dbus_list_get_next_link (&context->servers, link);
904
        }
905
      _dbus_list_clear (&context->servers);
906

907
      if (context->policy)
908
        {
909 910
          bus_policy_unref (context->policy);
          context->policy = NULL;
911
        }
912
      
913 914
      if (context->loop)
        {
915
          _dbus_loop_unref (context->loop);
916 917
          context->loop = NULL;
        }
918 919 920 921 922 923

      if (context->matchmaker)
        {
          bus_matchmaker_unref (context->matchmaker);
          context->matchmaker = NULL;
        }
924
      
925
      dbus_free (context->config_file);
926
      dbus_free (context->type);
927
      dbus_free (context->address);
928
      dbus_free (context->user);
929 930 931 932 933 934 935 936 937 938 939 940 941 942

      if (context->pidfile)
	{
          DBusString u;
          _dbus_string_init_const (&u, context->pidfile);

          /* Deliberately ignore errors here, since there's not much
	   * we can do about it, and we're exiting anyways.
	   */
	  _dbus_delete_file (&u, NULL);

          dbus_free (context->pidfile); 
	}

943 944
      if (context->user_database != NULL)
	_dbus_user_database_unref (context->user_database);
945
      
946
      dbus_free (context);
947

948
      dbus_server_free_data_slot (&server_data_slot);
949 950 951
    }
}

952 953 954 955 956 957 958
/* type may be NULL */
const char*
bus_context_get_type (BusContext *context)
{
  return context->type;
}

959 960 961 962 963 964
const char*
bus_context_get_address (BusContext *context)
{
  return context->address;
}

965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981
BusRegistry*
bus_context_get_registry (BusContext  *context)
{
  return context->registry;
}

BusConnections*
bus_context_get_connections (BusContext  *context)
{
  return context->connections;
}

BusActivation*
bus_context_get_activation (BusContext  *context)
{
  return context->activation;
}
982

983 984 985 986 987 988
BusMatchmaker*
bus_context_get_matchmaker (BusContext  *context)
{
  return context->matchmaker;
}

989
DBusLoop*
990 991 992 993 994
bus_context_get_loop (BusContext *context)
{
  return context->loop;
}

995 996 997 998 999 1000
DBusUserDatabase*
bus_context_get_user_database (BusContext *context)
{
  return context->user_database;
}

1001 1002 1003 1004
dbus_bool_t
bus_context_allow_user (BusContext   *context,
                        unsigned long uid)
{
1005 1006 1007
  return bus_policy_allow_user (context->policy,
                                context->user_database,
                                uid);
1008 1009
}

1010 1011 1012 1013 1014 1015
BusPolicy *
bus_context_get_policy (BusContext *context)
{
  return context->policy;
}

1016 1017
BusClientPolicy*
bus_context_create_client_policy (BusContext      *context,
1018 1019
                                  DBusConnection  *connection,
                                  DBusError       *error)
1020
{
1021 1022 1023
  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
  return bus_policy_create_client_policy (context->policy, connection,
                                          error);
1024
}
1025 1026 1027 1028 1029

int
bus_context_get_activation_timeout (BusContext *context)
{
  
1030
  return context->limits.activation_timeout;
1031
}
1032

1033 1034 1035
int
bus_context_get_auth_timeout (BusContext *context)
{
1036
  return context->limits.auth_timeout;
1037 1038 1039 1040 1041
}

int
bus_context_get_max_completed_connections (BusContext *context)
{
1042
  return context->limits.max_completed_connections;
1043 1044 1045 1046 1047
}

int
bus_context_get_max_incomplete_connections (BusContext *context)
{
1048
  return context->limits.max_incomplete_connections;
1049 1050 1051 1052 1053
}

int
bus_context_get_max_connections_per_user (BusContext *context)
{
1054
  return context->limits.max_connections_per_user;
1055 1056
}

1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068
int
bus_context_get_max_pending_activations (BusContext *context)
{
  return context->limits.max_pending_activations;
}

int
bus_context_get_max_services_per_connection (BusContext *context)
{
  return context->limits.max_services_per_connection;
}

1069 1070 1071 1072 1073 1074
int
bus_context_get_max_match_rules_per_connection (BusContext *context)
{
  return context->limits.max_match_rules_per_connection;
}

1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086
int
bus_context_get_max_replies_per_connection (BusContext *context)
{
  return context->limits.max_replies_per_connection;
}

int
bus_context_get_reply_timeout (BusContext *context)
{
  return context->limits.reply_timeout;
}

1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099
/*
 * addressed_recipient is the recipient specified in the message.
 *
 * proposed_recipient is the recipient we're considering sending
 * to right this second, and may be an eavesdropper.
 *
 * sender is the sender of the message.
 *
 * NULL for proposed_recipient or sender definitely means the bus driver.
 *
 * NULL for addressed_recipient may mean the bus driver, or may mean
 * no destination was specified in the message (e.g. a signal).
 */
1100 1101
dbus_bool_t
bus_context_check_security_policy (BusContext     *context,
1102
                                   BusTransaction *transaction,
1103
                                   DBusConnection *sender,
1104 1105
                                   DBusConnection *addressed_recipient,
                                   DBusConnection *proposed_recipient,
1106 1107 1108 1109 1110
                                   DBusMessage    *message,
                                   DBusError      *error)
{
  BusClientPolicy *sender_policy;
  BusClientPolicy *recipient_policy;
1111
  int type;
1112
  dbus_bool_t requested_reply;
1113 1114 1115 1116 1117
  
  type = dbus_message_get_type (message);
  
  /* dispatch.c was supposed to ensure these invariants */
  _dbus_assert (dbus_message_get_destination (message) != NULL ||
1118 1119
                type == DBUS_MESSAGE_TYPE_SIGNAL ||
                (sender == NULL && !bus_connection_is_active (proposed_recipient)));
1120 1121
  _dbus_assert (type == DBUS_MESSAGE_TYPE_SIGNAL ||
                addressed_recipient != NULL ||
1122
                strcmp (dbus_message_get_destination (message), DBUS_SERVICE_DBUS) == 0);
1123
  
1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143
  switch (type)
    {
    case DBUS_MESSAGE_TYPE_METHOD_CALL:
    case DBUS_MESSAGE_TYPE_SIGNAL:
    case DBUS_MESSAGE_TYPE_METHOD_RETURN:
    case DBUS_MESSAGE_TYPE_ERROR:
      break;
      
    default:
      _dbus_verbose ("security check disallowing message of unknown type %d\n",
                     type);

      dbus_set_error (error, DBUS_ERROR_ACCESS_DENIED,
                      "Message bus will not accept messages of unknown type\n");
              
      return FALSE;
    }

  requested_reply = FALSE;
  
1144 1145
  if (sender != NULL)
    {
1146 1147 1148 1149
      const char *dest;

      dest = dbus_message_get_destination (message);
	
1150 1151 1152
      /* First verify the SELinux access controls.  If allowed then
       * go on with the standard checks.
       */
1153 1154 1155 1156 1157
      if (!bus_selinux_allows_send (sender, proposed_recipient,
				    dbus_message_type_to_string (dbus_message_get_type (message)),
				    dbus_message_get_interface (message),
				    dbus_message_get_member (message),
				    dbus_message_get_error_name (message),
1158
				    dest ? dest : DBUS_SERVICE_DBUS, error))
1159
        {
1160 1161 1162 1163 1164 1165 1166 1167

	  if (dbus_error_is_set (error) &&
	      dbus_error_has_name (error, DBUS_ERROR_NO_MEMORY))
	    {
	      return FALSE;
	    }
	  

1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178
          dbus_set_error (error, DBUS_ERROR_ACCESS_DENIED,
                          "An SELinux policy prevents this sender "
                          "from sending this message to this recipient "
                          "(rejected message had interface \"%s\" "
                          "member \"%s\" error name \"%s\" destination \"%s\")",
                          dbus_message_get_interface (message) ?
                          dbus_message_get_interface (message) : "(unset)",
                          dbus_message_get_member (message) ?
                          dbus_message_get_member (message) : "(unset)",
                          dbus_message_get_error_name (message) ?
                          dbus_message_get_error_name (message) : "(unset)",
1179
                          dest ? dest : DBUS_SERVICE_DBUS);
1180 1181 1182 1183
          _dbus_verbose ("SELinux security check denying send to service\n");
          return FALSE;
        }
       
1184
      if (bus_connection_is_active (sender))
1185
        {
1186 1187
          sender_policy = bus_connection_get_policy (sender);
          _dbus_assert (sender_policy != NULL);
1188 1189 1190 1191 1192
          
          /* Fill in requested_reply variable with TRUE if this is a
           * reply and the reply was pending.
           */
          if (dbus_message_get_reply_serial (message) != 0)
1193 1194
            {
              if (proposed_recipient != NULL /* not to the bus driver */ &&
1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209
                  addressed_recipient == proposed_recipient /* not eavesdropping */)
                {
                  DBusError error2;                  
                  
                  dbus_error_init (&error2);
                  requested_reply = bus_connections_check_reply (bus_connection_get_connections (sender),
                                                                 transaction,
                                                                 sender, addressed_recipient, message,
                                                                 &error2);
                  if (dbus_error_is_set (&error2))
                    {
                      dbus_move_error (&error2, error);
                      return FALSE;
                    }
                }
1210
            }
1211 1212 1213 1214 1215 1216
        }
      else
        {
          /* Policy for inactive connections is that they can only send
           * the hello message to the bus driver
           */
1217
          if (proposed_recipient == NULL &&
1218
              dbus_message_is_method_call (message,
1219
                                           DBUS_INTERFACE_DBUS,
1220
                                           "Hello"))
1221 1222
            {
              _dbus_verbose ("security check allowing %s message\n",
1223
                             "Hello");
1224 1225 1226 1227 1228
              return TRUE;
            }
          else
            {
              _dbus_verbose ("security check disallowing non-%s message\n",
1229
                             "Hello");
1230 1231 1232

              dbus_set_error (error, DBUS_ERROR_ACCESS_DENIED,
                              "Client tried to send a message other than %s without being registered",
1233
                              "Hello");
1234 1235 1236
              
              return FALSE;
            }
1237
        }
1238 1239
    }
  else
1240 1241 1242 1243 1244 1245 1246 1247 1248 1249
    {
      sender_policy = NULL;

      /* If the sender is the bus driver, we assume any reply was a
       * requested reply as bus driver won't send bogus ones
       */
      if (addressed_recipient == proposed_recipient /* not eavesdropping */ &&
          dbus_message_get_reply_serial (message) != 0)
        requested_reply = TRUE;
    }
1250

1251 1252 1253
  _dbus_assert ((sender != NULL && sender_policy != NULL) ||
                (sender == NULL && sender_policy == NULL));
  
1254
  if (proposed_recipient != NULL)
1255
    {
1256 1257 1258 1259
      /* only the bus driver can send to an inactive recipient (as it
       * owns no services, so other apps can't address it). Inactive
       * recipients can receive any message.
       */
1260
      if (bus_connection_is_active (proposed_recipient))
1261
        {
1262
          recipient_policy = bus_connection_get_policy (proposed_recipient);
1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273
          _dbus_assert (recipient_policy != NULL);
        }
      else if (sender == NULL)
        {
          _dbus_verbose ("security check using NULL recipient policy for message from bus\n");
          recipient_policy = NULL;
        }
      else
        {
          _dbus_assert_not_reached ("a message was somehow sent to an inactive recipient from a source other than the message bus\n");
          recipient_policy = NULL;
1274
        }
1275 1276 1277
    }
  else
    recipient_policy = NULL;
1278
  
1279 1280 1281
  _dbus_assert ((proposed_recipient != NULL && recipient_policy != NULL) ||
                (proposed_recipient != NULL && sender == NULL && recipient_policy == NULL) ||
                (proposed_recipient == NULL && recipient_policy == NULL));
1282 1283
  
  if (sender_policy &&
1284
      !bus_client_policy_check_can_send (sender_policy,
1285 1286 1287
                                         context->registry,
                                         requested_reply,
                                         proposed_recipient,
1288 1289
                                         message))
    {
1290 1291 1292
      const char *dest;

      dest = dbus_message_get_destination (message);
1293 1294 1295 1296
      dbus_set_error (error, DBUS_ERROR_ACCESS_DENIED,
                      "A security policy in place prevents this sender "
                      "from sending this message to this recipient, "
                      "see message bus configuration file (rejected message "
1297 1298 1299 1300 1301 1302 1303
                      "had interface \"%s\" member \"%s\" error name \"%s\" destination \"%s\")",
                      dbus_message_get_interface (message) ?
                      dbus_message_get_interface (message) : "(unset)",
                      dbus_message_get_member (message) ?
                      dbus_message_get_member (message) : "(unset)",
                      dbus_message_get_error_name (message) ?
                      dbus_message_get_error_name (message) : "(unset)",
1304
                      dest ? dest : DBUS_SERVICE_DBUS);
1305
      _dbus_verbose ("security policy disallowing message due to sender policy\n");
1306 1307 1308
      return FALSE;
    }

1309
  if (recipient_policy &&
1310
      !bus_client_policy_check_can_receive (recipient_policy,
1311 1312 1313
                                            context->registry,
                                            requested_reply,
                                            sender,
1314
                                            addressed_recipient, proposed_recipient,
1315 1316
                                            message))
    {
1317 1318 1319
      const char *dest;

      dest = dbus_message_get_destination (message);
1320 1321 1322 1323
      dbus_set_error (error, DBUS_ERROR_ACCESS_DENIED,
                      "A security policy in place prevents this recipient "
                      "from receiving this message from this sender, "
                      "see message bus configuration file (rejected message "
1324
                      "had interface \"%s\" member \"%s\" error name \"%s\" destination \"%s\" reply serial %u requested_reply=%d)",
1325 1326 1327 1328 1329 1330
                      dbus_message_get_interface (message) ?
                      dbus_message_get_interface (message) : "(unset)",
                      dbus_message_get_member (message) ?
                      dbus_message_get_member (message) : "(unset)",
                      dbus_message_get_error_name (message) ?
                      dbus_message_get_error_name (message) : "(unset)",
1331
                      dest ? dest : DBUS_SERVICE_DBUS,
1332 1333
                      dbus_message_get_reply_serial (message),
                      requested_reply);
1334
      _dbus_verbose ("security policy disallowing message due to recipient policy\n");
1335 1336 1337
      return FALSE;
    }

1338
  /* See if limits on size have been exceeded */
1339 1340
  if (proposed_recipient &&
      dbus_connection_get_outgoing_size (proposed_recipient) >
1341
      context->limits.max_outgoing_bytes)
1342
    {
1343 1344 1345
      const char *dest;

      dest = dbus_message_get_destination (message);
1346 1347
      dbus_set_error (error, DBUS_ERROR_LIMITS_EXCEEDED,
                      "The destination service \"%s\" has a full message queue",
1348 1349
                      dest ? dest : (proposed_recipient ?
                                     bus_connection_get_name (proposed_recipient) : 
1350
                                     DBUS_SERVICE_DBUS));
1351
      _dbus_verbose ("security policy disallowing message due to full message queue\n");
1352 1353
      return FALSE;
    }
1354

1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371
  if (type == DBUS_MESSAGE_TYPE_METHOD_CALL)
    {
      /* Record that we will allow a reply here in the future (don't
       * bother if the recipient is the bus). Only the addressed recipient
       * may reply.
       */
      if (sender && addressed_recipient &&
          !bus_connections_expect_reply (bus_connection_get_connections (sender),
                                         transaction,
                                         sender, addressed_recipient,
                                         message, error))
        {
          _dbus_verbose ("Failed to record reply expectation or problem with the message expecting a reply\n");
          return FALSE;
        }
    }
  
1372
  _dbus_verbose ("security policy allowing message\n");
1373 1374
  return TRUE;
}