bus.c revision c4371e4bc8a561cf91516d22f00c9512dc7e8e53 
1/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
2/* bus.c  message bus context object
3 *
4 * Copyright (C) 2003, 2004 Red Hat, Inc.
5 *
6 * Licensed under the Academic Free License version 2.1
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
21 *
22 */
23
24#include "bus.h"
25#include "activation.h"
26#include "connection.h"
27#include "services.h"
28#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#include <dbus/dbus-list.h>
35#include <dbus/dbus-hash.h>
36#include <dbus/dbus-credentials.h>
37#include <dbus/dbus-internals.h>
38
39struct BusContext
40{
41  int refcount;
42  DBusGUID uuid;
43  char *config_file;
44  char *type;
45  char *servicehelper;
46  char *address;
47  char *pidfile;
48  char *user;
49  char *log_prefix;
50  DBusLoop *loop;
51  DBusList *servers;
52  BusConnections *connections;
53  BusActivation *activation;
54  BusRegistry *registry;
55  BusPolicy *policy;
56  BusMatchmaker *matchmaker;
57  BusLimits limits;
58  unsigned int fork : 1;
59  unsigned int syslog : 1;
60  unsigned int keep_umask : 1;
61};
62
63static dbus_int32_t server_data_slot = -1;
64
65typedef struct
66{
67  BusContext *context;
68} BusServerData;
69
70#define BUS_SERVER_DATA(server) (dbus_server_get_data ((server), server_data_slot))
71
72static BusContext*
73server_get_context (DBusServer *server)
74{
75  BusContext *context;
76  BusServerData *bd;
77
78  if (!dbus_server_allocate_data_slot (&server_data_slot))
79    return NULL;
80
81  bd = BUS_SERVER_DATA (server);
82  if (bd == NULL)
83    {
84      dbus_server_free_data_slot (&server_data_slot);
85      return NULL;
86    }
87
88  context = bd->context;
89
90  dbus_server_free_data_slot (&server_data_slot);
91
92  return context;
93}
94
95static dbus_bool_t
96server_watch_callback (DBusWatch     *watch,
97                       unsigned int   condition,
98                       void          *data)
99{
100  /* FIXME this can be done in dbus-mainloop.c
101   * if the code in activation.c for the babysitter
102   * watch handler is fixed.
103   */
104
105  return dbus_watch_handle (watch, condition);
106}
107
108static dbus_bool_t
109add_server_watch (DBusWatch  *watch,
110                  void       *data)
111{
112  DBusServer *server = data;
113  BusContext *context;
114
115  context = server_get_context (server);
116
117  return _dbus_loop_add_watch (context->loop,
118                               watch, server_watch_callback, server,
119                               NULL);
120}
121
122static void
123remove_server_watch (DBusWatch  *watch,
124                     void       *data)
125{
126  DBusServer *server = data;
127  BusContext *context;
128
129  context = server_get_context (server);
130
131  _dbus_loop_remove_watch (context->loop,
132                           watch, server_watch_callback, server);
133}
134
135
136static void
137server_timeout_callback (DBusTimeout   *timeout,
138                         void          *data)
139{
140  /* can return FALSE on OOM but we just let it fire again later */
141  dbus_timeout_handle (timeout);
142}
143
144static dbus_bool_t
145add_server_timeout (DBusTimeout *timeout,
146                    void        *data)
147{
148  DBusServer *server = data;
149  BusContext *context;
150
151  context = server_get_context (server);
152
153  return _dbus_loop_add_timeout (context->loop,
154                                 timeout, server_timeout_callback, server, NULL);
155}
156
157static void
158remove_server_timeout (DBusTimeout *timeout,
159                       void        *data)
160{
161  DBusServer *server = data;
162  BusContext *context;
163
164  context = server_get_context (server);
165
166  _dbus_loop_remove_timeout (context->loop,
167                             timeout, server_timeout_callback, server);
168}
169
170static void
171new_connection_callback (DBusServer     *server,
172                         DBusConnection *new_connection,
173                         void           *data)
174{
175  BusContext *context = data;
176
177  if (!bus_connections_setup_connection (context->connections, new_connection))
178    {
179      _dbus_verbose ("No memory to setup new connection\n");
180
181      /* if we don't do this, it will get unref'd without
182       * being disconnected... kind of strange really
183       * that we have to do this, people won't get it right
184       * in general.
185       */
186      dbus_connection_close (new_connection);
187    }
188
189  dbus_connection_set_max_received_size (new_connection,
190                                         context->limits.max_incoming_bytes);
191
192  dbus_connection_set_max_message_size (new_connection,
193                                        context->limits.max_message_size);
194
195  /* on OOM, we won't have ref'd the connection so it will die. */
196}
197
198static void
199free_server_data (void *data)
200{
201  BusServerData *bd = data;
202
203  dbus_free (bd);
204}
205
206static dbus_bool_t
207setup_server (BusContext *context,
208              DBusServer *server,
209              char      **auth_mechanisms,
210              DBusError  *error)
211{
212  BusServerData *bd;
213
214  bd = dbus_new0 (BusServerData, 1);
215  if (bd == NULL || !dbus_server_set_data (server,
216                                           server_data_slot,
217                                           bd, free_server_data))
218    {
219      dbus_free (bd);
220      BUS_SET_OOM (error);
221      return FALSE;
222    }
223
224  bd->context = context;
225
226  if (!dbus_server_set_auth_mechanisms (server, (const char**) auth_mechanisms))
227    {
228      BUS_SET_OOM (error);
229      return FALSE;
230    }
231
232  dbus_server_set_new_connection_function (server,
233                                           new_connection_callback,
234                                           context, NULL);
235
236  if (!dbus_server_set_watch_functions (server,
237                                        add_server_watch,
238                                        remove_server_watch,
239                                        NULL,
240                                        server,
241                                        NULL))
242    {
243      BUS_SET_OOM (error);
244      return FALSE;
245    }
246
247  if (!dbus_server_set_timeout_functions (server,
248                                          add_server_timeout,
249                                          remove_server_timeout,
250                                          NULL,
251                                          server, NULL))
252    {
253      BUS_SET_OOM (error);
254      return FALSE;
255    }
256
257  return TRUE;
258}
259
260/* This code only gets executed the first time the
261 * config files are parsed.  It is not executed
262 * when config files are reloaded.
263 */
264static dbus_bool_t
265process_config_first_time_only (BusContext      *context,
266				BusConfigParser *parser,
267				DBusError       *error)
268{
269  DBusString log_prefix;
270  DBusList *link;
271  DBusList **addresses;
272  const char *user, *pidfile;
273  char **auth_mechanisms;
274  DBusList **auth_mechanisms_list;
275  int len;
276  dbus_bool_t retval;
277
278  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
279
280  retval = FALSE;
281  auth_mechanisms = NULL;
282
283  /* Check for an existing pid file. Of course this is a race;
284   * we'd have to use fcntl() locks on the pid file to
285   * avoid that. But we want to check for the pid file
286   * before overwriting any existing sockets, etc.
287   */
288  pidfile = bus_config_parser_get_pidfile (parser);
289  if (pidfile != NULL)
290    {
291      DBusString u;
292      DBusStat stbuf;
293
294      _dbus_string_init_const (&u, pidfile);
295
296      if (_dbus_stat (&u, &stbuf, NULL))
297        {
298          dbus_set_error (error, DBUS_ERROR_FAILED,
299		                  "The pid file \"%s\" exists, if the message bus is not running, remove this file",
300                          pidfile);
301	      goto failed;
302        }
303    }
304
305  /* keep around the pid filename so we can delete it later */
306  context->pidfile = _dbus_strdup (pidfile);
307
308  /* note that type may be NULL */
309  context->type = _dbus_strdup (bus_config_parser_get_type (parser));
310  if (bus_config_parser_get_type (parser) != NULL && context->type == NULL)
311    goto oom;
312
313  user = bus_config_parser_get_user (parser);
314  if (user != NULL)
315    {
316      context->user = _dbus_strdup (user);
317      if (context->user == NULL)
318        goto oom;
319    }
320
321  /* Set up the prefix for syslog messages */
322  if (!_dbus_string_init (&log_prefix))
323    goto oom;
324  if (context->type && !strcmp (context->type, "system"))
325    {
326      if (!_dbus_string_append (&log_prefix, "[system] "))
327        goto oom;
328    }
329  else if (context->type && !strcmp (context->type, "session"))
330    {
331      DBusCredentials *credentials;
332
333      credentials = _dbus_credentials_new_from_current_process ();
334      if (!credentials)
335        goto oom;
336      if (!_dbus_string_append (&log_prefix, "[session "))
337        goto oom;
338      if (!_dbus_credentials_to_string_append (credentials, &log_prefix))
339        goto oom;
340      if (!_dbus_string_append (&log_prefix, "] "))
341        goto oom;
342      _dbus_credentials_unref (credentials);
343    }
344  if (!_dbus_string_steal_data (&log_prefix, &context->log_prefix))
345    goto oom;
346  _dbus_string_free (&log_prefix);
347
348  /* Build an array of auth mechanisms */
349
350  auth_mechanisms_list = bus_config_parser_get_mechanisms (parser);
351  len = _dbus_list_get_length (auth_mechanisms_list);
352
353  if (len > 0)
354    {
355      int i;
356
357      auth_mechanisms = dbus_new0 (char*, len + 1);
358      if (auth_mechanisms == NULL)
359        goto oom;
360
361      i = 0;
362      link = _dbus_list_get_first_link (auth_mechanisms_list);
363      while (link != NULL)
364        {
365          auth_mechanisms[i] = _dbus_strdup (link->data);
366          if (auth_mechanisms[i] == NULL)
367            goto oom;
368          link = _dbus_list_get_next_link (auth_mechanisms_list, link);
369        }
370    }
371  else
372    {
373      auth_mechanisms = NULL;
374    }
375
376  /* Listen on our addresses */
377
378  addresses = bus_config_parser_get_addresses (parser);
379
380  link = _dbus_list_get_first_link (addresses);
381  while (link != NULL)
382    {
383      DBusServer *server;
384
385      server = dbus_server_listen (link->data, error);
386      if (server == NULL)
387	{
388	  _DBUS_ASSERT_ERROR_IS_SET (error);
389	  goto failed;
390	}
391      else if (!setup_server (context, server, auth_mechanisms, error))
392	{
393	  _DBUS_ASSERT_ERROR_IS_SET (error);
394	  goto failed;
395	}
396
397      if (!_dbus_list_append (&context->servers, server))
398        goto oom;
399
400      link = _dbus_list_get_next_link (addresses, link);
401    }
402
403  context->fork = bus_config_parser_get_fork (parser);
404  context->syslog = bus_config_parser_get_syslog (parser);
405  context->keep_umask = bus_config_parser_get_keep_umask (parser);
406
407  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
408  retval = TRUE;
409
410 failed:
411  dbus_free_string_array (auth_mechanisms);
412  return retval;
413
414 oom:
415  BUS_SET_OOM (error);
416  dbus_free_string_array (auth_mechanisms);
417  return FALSE;
418}
419
420/* This code gets executed every time the config files
421 * are parsed: both during BusContext construction
422 * and on reloads. This function is slightly screwy
423 * since it can do a "half reload" in out-of-memory
424 * situations. Realistically, unlikely to ever matter.
425 */
426static dbus_bool_t
427process_config_every_time (BusContext      *context,
428			   BusConfigParser *parser,
429			   dbus_bool_t      is_reload,
430			   DBusError       *error)
431{
432  DBusString full_address;
433  DBusList *link;
434  DBusList **dirs;
435  BusActivation *new_activation;
436  char *addr;
437  const char *servicehelper;
438  char *s;
439
440  dbus_bool_t retval;
441
442  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
443
444  addr = NULL;
445  retval = FALSE;
446
447  if (!_dbus_string_init (&full_address))
448    {
449      BUS_SET_OOM (error);
450      return FALSE;
451    }
452
453  /* get our limits and timeout lengths */
454  bus_config_parser_get_limits (parser, &context->limits);
455
456  if (context->policy)
457    bus_policy_unref (context->policy);
458  context->policy = bus_config_parser_steal_policy (parser);
459  _dbus_assert (context->policy != NULL);
460
461  /* We have to build the address backward, so that
462   * <listen> later in the config file have priority
463   */
464  link = _dbus_list_get_last_link (&context->servers);
465  while (link != NULL)
466    {
467      addr = dbus_server_get_address (link->data);
468      if (addr == NULL)
469        {
470          BUS_SET_OOM (error);
471          goto failed;
472        }
473
474      if (_dbus_string_get_length (&full_address) > 0)
475        {
476          if (!_dbus_string_append (&full_address, ";"))
477            {
478              BUS_SET_OOM (error);
479              goto failed;
480            }
481        }
482
483      if (!_dbus_string_append (&full_address, addr))
484        {
485          BUS_SET_OOM (error);
486          goto failed;
487        }
488
489      dbus_free (addr);
490      addr = NULL;
491
492      link = _dbus_list_get_prev_link (&context->servers, link);
493    }
494
495  if (is_reload)
496    dbus_free (context->address);
497
498  if (!_dbus_string_copy_data (&full_address, &context->address))
499    {
500      BUS_SET_OOM (error);
501      goto failed;
502    }
503
504  /* get the service directories */
505  dirs = bus_config_parser_get_service_dirs (parser);
506
507  /* and the service helper */
508  servicehelper = bus_config_parser_get_servicehelper (parser);
509
510  s = _dbus_strdup(servicehelper);
511  if (s == NULL && servicehelper != NULL)
512    {
513      BUS_SET_OOM (error);
514      goto failed;
515    }
516  else
517    {
518      dbus_free(context->servicehelper);
519      context->servicehelper = s;
520    }
521
522  /* Create activation subsystem */
523  if (context->activation)
524    {
525      if (!bus_activation_reload (context->activation, &full_address, dirs, error))
526        goto failed;
527    }
528  else
529    {
530      context->activation = bus_activation_new (context, &full_address, dirs, error);
531    }
532
533  if (context->activation == NULL)
534    {
535      _DBUS_ASSERT_ERROR_IS_SET (error);
536      goto failed;
537    }
538
539  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
540  retval = TRUE;
541
542 failed:
543  _dbus_string_free (&full_address);
544
545  if (addr)
546    dbus_free (addr);
547
548  return retval;
549}
550
551static dbus_bool_t
552list_concat_new (DBusList **a,
553                 DBusList **b,
554                 DBusList **result)
555{
556  DBusList *link;
557
558  *result = NULL;
559
560  link = _dbus_list_get_first_link (a);
561  for (link = _dbus_list_get_first_link (a); link; link = _dbus_list_get_next_link (a, link))
562    {
563      if (!_dbus_list_append (result, link->data))
564        goto oom;
565    }
566  for (link = _dbus_list_get_first_link (b); link; link = _dbus_list_get_next_link (b, link))
567    {
568      if (!_dbus_list_append (result, link->data))
569        goto oom;
570    }
571
572  return TRUE;
573oom:
574  _dbus_list_clear (result);
575  return FALSE;
576}
577
578static dbus_bool_t
579process_config_postinit (BusContext      *context,
580			 BusConfigParser *parser,
581			 DBusError       *error)
582{
583  DBusHashTable *service_context_table;
584  DBusList *watched_dirs = NULL;
585
586  service_context_table = bus_config_parser_steal_service_context_table (parser);
587  if (!bus_registry_set_service_context_table (context->registry,
588					       service_context_table))
589    {
590      BUS_SET_OOM (error);
591      return FALSE;
592    }
593
594  _dbus_hash_table_unref (service_context_table);
595
596  /* We need to monitor both the configuration directories and directories
597   * containing .service files.
598   */
599  if (!list_concat_new (bus_config_parser_get_conf_dirs (parser),
600                        bus_config_parser_get_service_dirs (parser),
601                        &watched_dirs))
602    {
603      BUS_SET_OOM (error);
604      return FALSE;
605    }
606
607  bus_set_watched_dirs (context, &watched_dirs);
608
609  _dbus_list_clear (&watched_dirs);
610
611  return TRUE;
612}
613
614BusContext*
615bus_context_new (const DBusString *config_file,
616                 ForceForkSetting  force_fork,
617                 DBusPipe         *print_addr_pipe,
618                 DBusPipe         *print_pid_pipe,
619                 DBusError        *error)
620{
621  DBusString log_prefix;
622  BusContext *context;
623  BusConfigParser *parser;
624
625  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
626
627  context = NULL;
628  parser = NULL;
629
630  if (!dbus_server_allocate_data_slot (&server_data_slot))
631    {
632      BUS_SET_OOM (error);
633      return NULL;
634    }
635
636  context = dbus_new0 (BusContext, 1);
637  if (context == NULL)
638    {
639      BUS_SET_OOM (error);
640      goto failed;
641    }
642  context->refcount = 1;
643
644  _dbus_generate_uuid (&context->uuid);
645
646  if (!_dbus_string_copy_data (config_file, &context->config_file))
647    {
648      BUS_SET_OOM (error);
649      goto failed;
650    }
651
652  context->loop = _dbus_loop_new ();
653  if (context->loop == NULL)
654    {
655      BUS_SET_OOM (error);
656      goto failed;
657    }
658
659  context->registry = bus_registry_new (context);
660  if (context->registry == NULL)
661    {
662      BUS_SET_OOM (error);
663      goto failed;
664    }
665
666  parser = bus_config_load (config_file, TRUE, NULL, error);
667  if (parser == NULL)
668    {
669      _DBUS_ASSERT_ERROR_IS_SET (error);
670      goto failed;
671    }
672
673  if (!process_config_first_time_only (context, parser, error))
674    {
675      _DBUS_ASSERT_ERROR_IS_SET (error);
676      goto failed;
677    }
678  if (!process_config_every_time (context, parser, FALSE, error))
679    {
680      _DBUS_ASSERT_ERROR_IS_SET (error);
681      goto failed;
682    }
683
684  /* we need another ref of the server data slot for the context
685   * to own
686   */
687  if (!dbus_server_allocate_data_slot (&server_data_slot))
688    _dbus_assert_not_reached ("second ref of server data slot failed");
689
690  /* Note that we don't know whether the print_addr_pipe is
691   * one of the sockets we're using to listen on, or some
692   * other random thing. But I think the answer is "don't do
693   * that then"
694   */
695  if (print_addr_pipe != NULL && _dbus_pipe_is_valid (print_addr_pipe))
696    {
697      DBusString addr;
698      const char *a = bus_context_get_address (context);
699      int bytes;
700
701      _dbus_assert (a != NULL);
702      if (!_dbus_string_init (&addr))
703        {
704          BUS_SET_OOM (error);
705          goto failed;
706        }
707
708      if (!_dbus_string_append (&addr, a) ||
709          !_dbus_string_append (&addr, "\n"))
710        {
711          _dbus_string_free (&addr);
712          BUS_SET_OOM (error);
713          goto failed;
714        }
715
716      bytes = _dbus_string_get_length (&addr);
717      if (_dbus_pipe_write (print_addr_pipe, &addr, 0, bytes, error) != bytes)
718        {
719          /* pipe write returns an error on failure but not short write */
720          if (error != NULL && !dbus_error_is_set (error))
721            {
722              dbus_set_error (error, DBUS_ERROR_FAILED,
723                              "Printing message bus address: did not write all bytes\n");
724            }
725          _dbus_string_free (&addr);
726          goto failed;
727        }
728
729      if (!_dbus_pipe_is_stdout_or_stderr (print_addr_pipe))
730        _dbus_pipe_close (print_addr_pipe, NULL);
731
732      _dbus_string_free (&addr);
733    }
734
735  context->connections = bus_connections_new (context);
736  if (context->connections == NULL)
737    {
738      BUS_SET_OOM (error);
739      goto failed;
740    }
741
742  context->matchmaker = bus_matchmaker_new ();
743  if (context->matchmaker == NULL)
744    {
745      BUS_SET_OOM (error);
746      goto failed;
747    }
748
749  /* check user before we fork */
750  if (context->user != NULL)
751    {
752      if (!_dbus_verify_daemon_user (context->user))
753        {
754          dbus_set_error (error, DBUS_ERROR_FAILED,
755                          "Could not get UID and GID for username \"%s\"",
756                          context->user);
757          goto failed;
758        }
759    }
760
761  /* Now become a daemon if appropriate and write out pid file in any case */
762  {
763    DBusString u;
764
765    if (context->pidfile)
766      _dbus_string_init_const (&u, context->pidfile);
767
768    if ((force_fork != FORK_NEVER && context->fork) || force_fork == FORK_ALWAYS)
769      {
770        _dbus_verbose ("Forking and becoming daemon\n");
771
772        if (!_dbus_become_daemon (context->pidfile ? &u : NULL,
773                                  print_pid_pipe,
774                                  error,
775                                  context->keep_umask))
776          {
777            _DBUS_ASSERT_ERROR_IS_SET (error);
778            goto failed;
779          }
780      }
781    else
782      {
783        _dbus_verbose ("Fork not requested\n");
784
785        /* Need to write PID file and to PID pipe for ourselves,
786         * not for the child process. This is a no-op if the pidfile
787         * is NULL and print_pid_pipe is NULL.
788         */
789        if (!_dbus_write_pid_to_file_and_pipe (context->pidfile ? &u : NULL,
790                                               print_pid_pipe,
791                                               _dbus_getpid (),
792                                               error))
793          {
794            _DBUS_ASSERT_ERROR_IS_SET (error);
795            goto failed;
796          }
797      }
798  }
799
800  if (print_pid_pipe && _dbus_pipe_is_valid (print_pid_pipe) &&
801      !_dbus_pipe_is_stdout_or_stderr (print_pid_pipe))
802    _dbus_pipe_close (print_pid_pipe, NULL);
803
804  if (!bus_selinux_full_init ())
805    {
806      bus_context_log (context, DBUS_SYSTEM_LOG_FATAL, "SELinux enabled but AVC initialization failed; check system log\n");
807    }
808
809  if (!process_config_postinit (context, parser, error))
810    {
811      _DBUS_ASSERT_ERROR_IS_SET (error);
812      goto failed;
813    }
814
815  if (parser != NULL)
816    {
817      bus_config_parser_unref (parser);
818      parser = NULL;
819    }
820
821  /* Here we change our credentials if required,
822   * as soon as we've set up our sockets and pidfile
823   */
824  if (context->user != NULL)
825    {
826      if (!_dbus_change_to_daemon_user (context->user, error))
827	{
828	  _DBUS_ASSERT_ERROR_IS_SET (error);
829	  goto failed;
830	}
831
832#ifdef HAVE_SELINUX
833      /* FIXME - why not just put this in full_init() below? */
834      bus_selinux_audit_init ();
835#endif
836    }
837
838  dbus_server_free_data_slot (&server_data_slot);
839
840  return context;
841
842 failed:
843  if (parser != NULL)
844    bus_config_parser_unref (parser);
845  if (context != NULL)
846    bus_context_unref (context);
847
848  if (server_data_slot >= 0)
849    dbus_server_free_data_slot (&server_data_slot);
850
851  return NULL;
852}
853
854dbus_bool_t
855bus_context_get_id (BusContext       *context,
856                    DBusString       *uuid)
857{
858  return _dbus_uuid_encode (&context->uuid, uuid);
859}
860
861dbus_bool_t
862bus_context_reload_config (BusContext *context,
863			   DBusError  *error)
864{
865  BusConfigParser *parser;
866  DBusString config_file;
867  dbus_bool_t ret;
868
869  /* Flush the user database cache */
870  _dbus_flush_caches ();
871
872  ret = FALSE;
873  _dbus_string_init_const (&config_file, context->config_file);
874  parser = bus_config_load (&config_file, TRUE, NULL, error);
875  if (parser == NULL)
876    {
877      _DBUS_ASSERT_ERROR_IS_SET (error);
878      goto failed;
879    }
880
881  if (!process_config_every_time (context, parser, TRUE, error))
882    {
883      _DBUS_ASSERT_ERROR_IS_SET (error);
884      goto failed;
885    }
886  if (!process_config_postinit (context, parser, error))
887    {
888      _DBUS_ASSERT_ERROR_IS_SET (error);
889      goto failed;
890    }
891  ret = TRUE;
892
893  bus_context_log (context, DBUS_SYSTEM_LOG_INFO, "Reloaded configuration");
894 failed:
895  if (!ret)
896    bus_context_log (context, DBUS_SYSTEM_LOG_INFO, "Unable to reload configuration: %s", error->message);
897  if (parser != NULL)
898    bus_config_parser_unref (parser);
899  return ret;
900}
901
902static void
903shutdown_server (BusContext *context,
904                 DBusServer *server)
905{
906  if (server == NULL ||
907      !dbus_server_get_is_connected (server))
908    return;
909
910  if (!dbus_server_set_watch_functions (server,
911                                        NULL, NULL, NULL,
912                                        context,
913                                        NULL))
914    _dbus_assert_not_reached ("setting watch functions to NULL failed");
915
916  if (!dbus_server_set_timeout_functions (server,
917                                          NULL, NULL, NULL,
918                                          context,
919                                          NULL))
920    _dbus_assert_not_reached ("setting timeout functions to NULL failed");
921
922  dbus_server_disconnect (server);
923}
924
925void
926bus_context_shutdown (BusContext  *context)
927{
928  DBusList *link;
929
930  link = _dbus_list_get_first_link (&context->servers);
931  while (link != NULL)
932    {
933      shutdown_server (context, link->data);
934
935      link = _dbus_list_get_next_link (&context->servers, link);
936    }
937}
938
939BusContext *
940bus_context_ref (BusContext *context)
941{
942  _dbus_assert (context->refcount > 0);
943  context->refcount += 1;
944
945  return context;
946}
947
948void
949bus_context_unref (BusContext *context)
950{
951  _dbus_assert (context->refcount > 0);
952  context->refcount -= 1;
953
954  if (context->refcount == 0)
955    {
956      DBusList *link;
957
958      _dbus_verbose ("Finalizing bus context %p\n", context);
959
960      bus_context_shutdown (context);
961
962      if (context->connections)
963        {
964          bus_connections_unref (context->connections);
965          context->connections = NULL;
966        }
967
968      if (context->registry)
969        {
970          bus_registry_unref (context->registry);
971          context->registry = NULL;
972        }
973
974      if (context->activation)
975        {
976          bus_activation_unref (context->activation);
977          context->activation = NULL;
978        }
979
980      link = _dbus_list_get_first_link (&context->servers);
981      while (link != NULL)
982        {
983          dbus_server_unref (link->data);
984
985          link = _dbus_list_get_next_link (&context->servers, link);
986        }
987      _dbus_list_clear (&context->servers);
988
989      if (context->policy)
990        {
991          bus_policy_unref (context->policy);
992          context->policy = NULL;
993        }
994
995      if (context->loop)
996        {
997          _dbus_loop_unref (context->loop);
998          context->loop = NULL;
999        }
1000
1001      if (context->matchmaker)
1002        {
1003          bus_matchmaker_unref (context->matchmaker);
1004          context->matchmaker = NULL;
1005        }
1006
1007      dbus_free (context->config_file);
1008      dbus_free (context->log_prefix);
1009      dbus_free (context->type);
1010      dbus_free (context->address);
1011      dbus_free (context->user);
1012      dbus_free (context->servicehelper);
1013
1014      if (context->pidfile)
1015	{
1016          DBusString u;
1017          _dbus_string_init_const (&u, context->pidfile);
1018
1019          /* Deliberately ignore errors here, since there's not much
1020	   * we can do about it, and we're exiting anyways.
1021	   */
1022	  _dbus_delete_file (&u, NULL);
1023
1024          dbus_free (context->pidfile);
1025	}
1026      dbus_free (context);
1027
1028      dbus_server_free_data_slot (&server_data_slot);
1029    }
1030}
1031
1032/* type may be NULL */
1033const char*
1034bus_context_get_type (BusContext *context)
1035{
1036  return context->type;
1037}
1038
1039const char*
1040bus_context_get_address (BusContext *context)
1041{
1042  return context->address;
1043}
1044
1045const char*
1046bus_context_get_servicehelper (BusContext *context)
1047{
1048  return context->servicehelper;
1049}
1050
1051BusRegistry*
1052bus_context_get_registry (BusContext  *context)
1053{
1054  return context->registry;
1055}
1056
1057BusConnections*
1058bus_context_get_connections (BusContext  *context)
1059{
1060  return context->connections;
1061}
1062
1063BusActivation*
1064bus_context_get_activation (BusContext  *context)
1065{
1066  return context->activation;
1067}
1068
1069BusMatchmaker*
1070bus_context_get_matchmaker (BusContext  *context)
1071{
1072  return context->matchmaker;
1073}
1074
1075DBusLoop*
1076bus_context_get_loop (BusContext *context)
1077{
1078  return context->loop;
1079}
1080
1081dbus_bool_t
1082bus_context_allow_unix_user (BusContext   *context,
1083                             unsigned long uid)
1084{
1085  return bus_policy_allow_unix_user (context->policy,
1086                                     uid);
1087}
1088
1089/* For now this is never actually called because the default
1090 * DBusConnection behavior of 'same user that owns the bus can connect'
1091 * is all it would do.
1092 */
1093dbus_bool_t
1094bus_context_allow_windows_user (BusContext       *context,
1095                                const char       *windows_sid)
1096{
1097  return bus_policy_allow_windows_user (context->policy,
1098                                        windows_sid);
1099}
1100
1101BusPolicy *
1102bus_context_get_policy (BusContext *context)
1103{
1104  return context->policy;
1105}
1106
1107BusClientPolicy*
1108bus_context_create_client_policy (BusContext      *context,
1109                                  DBusConnection  *connection,
1110                                  DBusError       *error)
1111{
1112  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
1113  return bus_policy_create_client_policy (context->policy, connection,
1114                                          error);
1115}
1116
1117int
1118bus_context_get_activation_timeout (BusContext *context)
1119{
1120
1121  return context->limits.activation_timeout;
1122}
1123
1124int
1125bus_context_get_auth_timeout (BusContext *context)
1126{
1127  return context->limits.auth_timeout;
1128}
1129
1130int
1131bus_context_get_max_completed_connections (BusContext *context)
1132{
1133  return context->limits.max_completed_connections;
1134}
1135
1136int
1137bus_context_get_max_incomplete_connections (BusContext *context)
1138{
1139  return context->limits.max_incomplete_connections;
1140}
1141
1142int
1143bus_context_get_max_connections_per_user (BusContext *context)
1144{
1145  return context->limits.max_connections_per_user;
1146}
1147
1148int
1149bus_context_get_max_pending_activations (BusContext *context)
1150{
1151  return context->limits.max_pending_activations;
1152}
1153
1154int
1155bus_context_get_max_services_per_connection (BusContext *context)
1156{
1157  return context->limits.max_services_per_connection;
1158}
1159
1160int
1161bus_context_get_max_match_rules_per_connection (BusContext *context)
1162{
1163  return context->limits.max_match_rules_per_connection;
1164}
1165
1166int
1167bus_context_get_max_replies_per_connection (BusContext *context)
1168{
1169  return context->limits.max_replies_per_connection;
1170}
1171
1172int
1173bus_context_get_reply_timeout (BusContext *context)
1174{
1175  return context->limits.reply_timeout;
1176}
1177
1178void
1179bus_context_log (BusContext *context, DBusSystemLogSeverity severity, const char *msg, ...)
1180{
1181  va_list args;
1182
1183  if (!context->syslog)
1184    return;
1185
1186  va_start (args, msg);
1187
1188  if (context->log_prefix)
1189    {
1190      DBusString full_msg;
1191
1192      if (!_dbus_string_init (&full_msg))
1193        goto out;
1194      if (!_dbus_string_append (&full_msg, context->log_prefix))
1195        goto oom_out;
1196      if (!_dbus_string_append_printf_valist (&full_msg, msg, args))
1197        goto oom_out;
1198
1199      _dbus_system_log (severity, "%s", _dbus_string_get_const_data (&full_msg));
1200    oom_out:
1201      _dbus_string_free (&full_msg);
1202    }
1203  else
1204    _dbus_system_logv (severity, msg, args);
1205
1206out:
1207  va_end (args);
1208}
1209
1210/*
1211 * addressed_recipient is the recipient specified in the message.
1212 *
1213 * proposed_recipient is the recipient we're considering sending
1214 * to right this second, and may be an eavesdropper.
1215 *
1216 * sender is the sender of the message.
1217 *
1218 * NULL for proposed_recipient or sender definitely means the bus driver.
1219 *
1220 * NULL for addressed_recipient may mean the bus driver, or may mean
1221 * no destination was specified in the message (e.g. a signal).
1222 */
1223dbus_bool_t
1224bus_context_check_security_policy (BusContext     *context,
1225                                   BusTransaction *transaction,
1226                                   DBusConnection *sender,
1227                                   DBusConnection *addressed_recipient,
1228                                   DBusConnection *proposed_recipient,
1229                                   DBusMessage    *message,
1230                                   DBusError      *error)
1231{
1232  const char *dest;
1233  BusClientPolicy *sender_policy;
1234  BusClientPolicy *recipient_policy;
1235  dbus_int32_t toggles;
1236  dbus_bool_t log;
1237  int type;
1238  dbus_bool_t requested_reply;
1239  const char *sender_name;
1240  const char *sender_loginfo;
1241  const char *proposed_recipient_loginfo;
1242
1243  type = dbus_message_get_type (message);
1244  dest = dbus_message_get_destination (message);
1245
1246  /* dispatch.c was supposed to ensure these invariants */
1247  _dbus_assert (dest != NULL ||
1248                type == DBUS_MESSAGE_TYPE_SIGNAL ||
1249                (sender == NULL && !bus_connection_is_active (proposed_recipient)));
1250  _dbus_assert (type == DBUS_MESSAGE_TYPE_SIGNAL ||
1251                addressed_recipient != NULL ||
1252                strcmp (dest, DBUS_SERVICE_DBUS) == 0);
1253
1254  /* Used in logging below */
1255  if (sender != NULL)
1256    {
1257      sender_name = bus_connection_get_name (sender);
1258      sender_loginfo = bus_connection_get_loginfo (sender);
1259    }
1260  else
1261    {
1262      sender_name = NULL;
1263      sender_loginfo = "(bus)";
1264    }
1265
1266  if (proposed_recipient != NULL)
1267    proposed_recipient_loginfo = bus_connection_get_loginfo (proposed_recipient);
1268  else
1269    proposed_recipient_loginfo = "bus";
1270
1271  switch (type)
1272    {
1273    case DBUS_MESSAGE_TYPE_METHOD_CALL:
1274    case DBUS_MESSAGE_TYPE_SIGNAL:
1275    case DBUS_MESSAGE_TYPE_METHOD_RETURN:
1276    case DBUS_MESSAGE_TYPE_ERROR:
1277      break;
1278
1279    default:
1280      _dbus_verbose ("security check disallowing message of unknown type %d\n",
1281                     type);
1282
1283      dbus_set_error (error, DBUS_ERROR_ACCESS_DENIED,
1284                      "Message bus will not accept messages of unknown type\n");
1285
1286      return FALSE;
1287    }
1288
1289  requested_reply = FALSE;
1290
1291  if (sender != NULL)
1292    {
1293      /* First verify the SELinux access controls.  If allowed then
1294       * go on with the standard checks.
1295       */
1296      if (!bus_selinux_allows_send (sender, proposed_recipient,
1297				    dbus_message_type_to_string (dbus_message_get_type (message)),
1298				    dbus_message_get_interface (message),
1299				    dbus_message_get_member (message),
1300				    dbus_message_get_error_name (message),
1301				    dest ? dest : DBUS_SERVICE_DBUS, error))
1302        {
1303          if (error != NULL && !dbus_error_is_set (error))
1304            {
1305              dbus_set_error (error, DBUS_ERROR_ACCESS_DENIED,
1306                              "An SELinux policy prevents this sender "
1307                              "from sending this message to this recipient "
1308                              "(rejected message had sender \"%s\" interface \"%s\" "
1309                              "member \"%s\" error name \"%s\" destination \"%s\")",
1310                              sender_name ? sender_name : "(unset)",
1311                              dbus_message_get_interface (message) ?
1312                              dbus_message_get_interface (message) : "(unset)",
1313                              dbus_message_get_member (message) ?
1314                              dbus_message_get_member (message) : "(unset)",
1315                              dbus_message_get_error_name (message) ?
1316                              dbus_message_get_error_name (message) : "(unset)",
1317                              dest ? dest : DBUS_SERVICE_DBUS);
1318              _dbus_verbose ("SELinux security check denying send to service\n");
1319            }
1320
1321          return FALSE;
1322        }
1323
1324      if (bus_connection_is_active (sender))
1325        {
1326          sender_policy = bus_connection_get_policy (sender);
1327          _dbus_assert (sender_policy != NULL);
1328
1329          /* Fill in requested_reply variable with TRUE if this is a
1330           * reply and the reply was pending.
1331           */
1332          if (dbus_message_get_reply_serial (message) != 0)
1333            {
1334              if (proposed_recipient != NULL /* not to the bus driver */ &&
1335                  addressed_recipient == proposed_recipient /* not eavesdropping */)
1336                {
1337                  DBusError error2;
1338
1339                  dbus_error_init (&error2);
1340                  requested_reply = bus_connections_check_reply (bus_connection_get_connections (sender),
1341                                                                 transaction,
1342                                                                 sender, addressed_recipient, message,
1343                                                                 &error2);
1344                  if (dbus_error_is_set (&error2))
1345                    {
1346                      dbus_move_error (&error2, error);
1347                      return FALSE;
1348                    }
1349                }
1350            }
1351        }
1352      else
1353        {
1354          /* Policy for inactive connections is that they can only send
1355           * the hello message to the bus driver
1356           */
1357          if (proposed_recipient == NULL &&
1358              dbus_message_is_method_call (message,
1359                                           DBUS_INTERFACE_DBUS,
1360                                           "Hello"))
1361            {
1362              _dbus_verbose ("security check allowing %s message\n",
1363                             "Hello");
1364              return TRUE;
1365            }
1366          else
1367            {
1368              _dbus_verbose ("security check disallowing non-%s message\n",
1369                             "Hello");
1370
1371              dbus_set_error (error, DBUS_ERROR_ACCESS_DENIED,
1372                              "Client tried to send a message other than %s without being registered",
1373                              "Hello");
1374
1375              return FALSE;
1376            }
1377        }
1378    }
1379  else
1380    {
1381      sender_policy = NULL;
1382
1383      /* If the sender is the bus driver, we assume any reply was a
1384       * requested reply as bus driver won't send bogus ones
1385       */
1386      if (addressed_recipient == proposed_recipient /* not eavesdropping */ &&
1387          dbus_message_get_reply_serial (message) != 0)
1388        requested_reply = TRUE;
1389    }
1390
1391  _dbus_assert ((sender != NULL && sender_policy != NULL) ||
1392                (sender == NULL && sender_policy == NULL));
1393
1394  if (proposed_recipient != NULL)
1395    {
1396      /* only the bus driver can send to an inactive recipient (as it
1397       * owns no services, so other apps can't address it). Inactive
1398       * recipients can receive any message.
1399       */
1400      if (bus_connection_is_active (proposed_recipient))
1401        {
1402          recipient_policy = bus_connection_get_policy (proposed_recipient);
1403          _dbus_assert (recipient_policy != NULL);
1404        }
1405      else if (sender == NULL)
1406        {
1407          _dbus_verbose ("security check using NULL recipient policy for message from bus\n");
1408          recipient_policy = NULL;
1409        }
1410      else
1411        {
1412          _dbus_assert_not_reached ("a message was somehow sent to an inactive recipient from a source other than the message bus\n");
1413          recipient_policy = NULL;
1414        }
1415    }
1416  else
1417    recipient_policy = NULL;
1418
1419  _dbus_assert ((proposed_recipient != NULL && recipient_policy != NULL) ||
1420                (proposed_recipient != NULL && sender == NULL && recipient_policy == NULL) ||
1421                (proposed_recipient == NULL && recipient_policy == NULL));
1422
1423  log = FALSE;
1424  if (sender_policy &&
1425      !bus_client_policy_check_can_send (sender_policy,
1426                                         context->registry,
1427                                         requested_reply,
1428                                         proposed_recipient,
1429                                         message, &toggles, &log))
1430    {
1431      const char *msg = "Rejected send message, %d matched rules; "
1432                        "type=\"%s\", sender=\"%s\" (%s) interface=\"%s\" member=\"%s\" error name=\"%s\" requested_reply=%d destination=\"%s\" (%s))";
1433
1434      dbus_set_error (error, DBUS_ERROR_ACCESS_DENIED, msg,
1435                      toggles,
1436                      dbus_message_type_to_string (dbus_message_get_type (message)),
1437                      sender_name ? sender_name : "(unset)",
1438                      sender_loginfo,
1439                      dbus_message_get_interface (message) ?
1440                      dbus_message_get_interface (message) : "(unset)",
1441                      dbus_message_get_member (message) ?
1442                      dbus_message_get_member (message) : "(unset)",
1443                      dbus_message_get_error_name (message) ?
1444                      dbus_message_get_error_name (message) : "(unset)",
1445                      requested_reply,
1446                      dest ? dest : DBUS_SERVICE_DBUS,
1447                      proposed_recipient_loginfo);
1448      /* Needs to be duplicated to avoid calling malloc and having to handle OOM */
1449      if (addressed_recipient == proposed_recipient)
1450        bus_context_log (context, DBUS_SYSTEM_LOG_SECURITY, msg,
1451                                  toggles,
1452                                  dbus_message_type_to_string (dbus_message_get_type (message)),
1453                                  sender_name ? sender_name : "(unset)",
1454                                  sender_loginfo,
1455                                  dbus_message_get_interface (message) ?
1456                                  dbus_message_get_interface (message) : "(unset)",
1457                                  dbus_message_get_member (message) ?
1458                                  dbus_message_get_member (message) : "(unset)",
1459                                  dbus_message_get_error_name (message) ?
1460                                  dbus_message_get_error_name (message) : "(unset)",
1461                                  requested_reply,
1462                                  dest ? dest : DBUS_SERVICE_DBUS,
1463                                  proposed_recipient_loginfo);
1464      _dbus_verbose ("security policy disallowing message due to sender policy\n");
1465      return FALSE;
1466    }
1467
1468  if (log)
1469    bus_context_log (context, DBUS_SYSTEM_LOG_SECURITY,
1470                              "Would reject message, %d matched rules; "
1471                              "type=\"%s\", sender=\"%s\" (%s) interface=\"%s\" member=\"%s\" error name=\"%s\" requested_reply=%d destination=\"%s\" (%s))",
1472                              toggles,
1473                              dbus_message_type_to_string (dbus_message_get_type (message)),
1474                              sender_name ? sender_name : "(unset)",
1475                              sender_loginfo,
1476                              dbus_message_get_interface (message) ?
1477                              dbus_message_get_interface (message) : "(unset)",
1478                              dbus_message_get_member (message) ?
1479                              dbus_message_get_member (message) : "(unset)",
1480                              dbus_message_get_error_name (message) ?
1481                              dbus_message_get_error_name (message) : "(unset)",
1482                              requested_reply,
1483                              dest ? dest : DBUS_SERVICE_DBUS,
1484                              proposed_recipient_loginfo);
1485
1486  if (recipient_policy &&
1487      !bus_client_policy_check_can_receive (recipient_policy,
1488                                            context->registry,
1489                                            requested_reply,
1490                                            sender,
1491                                            addressed_recipient, proposed_recipient,
1492                                            message, &toggles))
1493    {
1494      const char *msg = "Rejected receive message, %d matched rules; "
1495                        "type=\"%s\" sender=\"%s\" (%s) interface=\"%s\" member=\"%s\" error name=\"%s\" reply serial=%u requested_reply=%d destination=\"%s\" (%s))";
1496
1497      dbus_set_error (error, DBUS_ERROR_ACCESS_DENIED, msg,
1498                      toggles,
1499                      dbus_message_type_to_string (dbus_message_get_type (message)),
1500                      sender_name ? sender_name : "(unset)",
1501                      sender_loginfo,
1502                      dbus_message_get_interface (message) ?
1503                      dbus_message_get_interface (message) : "(unset)",
1504                      dbus_message_get_member (message) ?
1505                      dbus_message_get_member (message) : "(unset)",
1506                      dbus_message_get_error_name (message) ?
1507                      dbus_message_get_error_name (message) : "(unset)",
1508                      dbus_message_get_reply_serial (message),
1509                      requested_reply,
1510                      dest ? dest : DBUS_SERVICE_DBUS,
1511                      proposed_recipient_loginfo);
1512      /* Needs to be duplicated to avoid calling malloc and having to handle OOM */
1513      if (addressed_recipient == proposed_recipient)
1514        bus_context_log (context, DBUS_SYSTEM_LOG_SECURITY, msg,
1515                                  toggles,
1516                                  dbus_message_type_to_string (dbus_message_get_type (message)),
1517                                  sender_name ? sender_name : "(unset)",
1518                                  sender_loginfo,
1519                                  dbus_message_get_interface (message) ?
1520                                  dbus_message_get_interface (message) : "(unset)",
1521                                  dbus_message_get_member (message) ?
1522                                  dbus_message_get_member (message) : "(unset)",
1523                                  dbus_message_get_error_name (message) ?
1524                                  dbus_message_get_error_name (message) : "(unset)",
1525                                  dbus_message_get_reply_serial (message),
1526                                  requested_reply,
1527                                  dest ? dest : DBUS_SERVICE_DBUS,
1528                                  proposed_recipient_loginfo);
1529      _dbus_verbose ("security policy disallowing message due to recipient policy\n");
1530      return FALSE;
1531    }
1532
1533  /* See if limits on size have been exceeded */
1534  if (proposed_recipient &&
1535      dbus_connection_get_outgoing_size (proposed_recipient) >
1536      context->limits.max_outgoing_bytes)
1537    {
1538      dbus_set_error (error, DBUS_ERROR_LIMITS_EXCEEDED,
1539                      "The destination service \"%s\" has a full message queue",
1540                      dest ? dest : (proposed_recipient ?
1541                                     bus_connection_get_name (proposed_recipient) :
1542                                     DBUS_SERVICE_DBUS));
1543      _dbus_verbose ("security policy disallowing message due to full message queue\n");
1544      return FALSE;
1545    }
1546
1547  /* Record that we will allow a reply here in the future (don't
1548   * bother if the recipient is the bus or this is an eavesdropping
1549   * connection). Only the addressed recipient may reply.
1550   */
1551  if (type == DBUS_MESSAGE_TYPE_METHOD_CALL &&
1552      sender &&
1553      addressed_recipient &&
1554      addressed_recipient == proposed_recipient && /* not eavesdropping */
1555      !bus_connections_expect_reply (bus_connection_get_connections (sender),
1556                                     transaction,
1557                                     sender, addressed_recipient,
1558                                     message, error))
1559    {
1560      _dbus_verbose ("Failed to record reply expectation or problem with the message expecting a reply\n");
1561      return FALSE;
1562    }
1563
1564  _dbus_verbose ("security policy allowing message\n");
1565  return TRUE;
1566}
1567