1 /* -*- mode: C; c-file-style: "gnu" -*- */
2 /* dbus-transport.c DBusTransport object (internal to D-Bus implementation)
3 *
4 * Copyright (C) 2002, 2003 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 *
22 */
23
24 #include "dbus-transport-protected.h"
25 #include "dbus-transport-unix.h"
26 #include "dbus-transport-socket.h"
27 #include "dbus-connection-internal.h"
28 #include "dbus-watch.h"
29 #include "dbus-auth.h"
30 #include "dbus-address.h"
31 #ifdef DBUS_BUILD_TESTS
32 #include "dbus-server-debug-pipe.h"
33 #endif
34
35 /**
36 * @defgroup DBusTransport DBusTransport object
37 * @ingroup DBusInternals
38 * @brief "Backend" for a DBusConnection.
39 *
40 * Types and functions related to DBusTransport. A transport is an
41 * abstraction that can send and receive data via various kinds of
42 * network connections or other IPC mechanisms.
43 *
44 * @{
45 */
46
47 /**
48 * @typedef DBusTransport
49 *
50 * Opaque object representing a way message stream.
51 * DBusTransport abstracts various kinds of actual
52 * transport mechanism, such as different network protocols,
53 * or encryption schemes.
54 */
55
56 static void
live_messages_size_notify(DBusCounter * counter,void * user_data)57 live_messages_size_notify (DBusCounter *counter,
58 void *user_data)
59 {
60 DBusTransport *transport = user_data;
61
62 _dbus_transport_ref (transport);
63
64 #if 0
65 _dbus_verbose ("Counter value is now %d\n",
66 (int) _dbus_counter_get_value (counter));
67 #endif
68
69 /* disable or re-enable the read watch for the transport if
70 * required.
71 */
72 if (transport->vtable->live_messages_changed)
73 (* transport->vtable->live_messages_changed) (transport);
74
75 _dbus_transport_unref (transport);
76 }
77
78 /**
79 * Initializes the base class members of DBusTransport. Chained up to
80 * by subclasses in their constructor. The server GUID is the
81 * globally unique ID for the server creating this connection
82 * and will be #NULL for the client side of a connection. The GUID
83 * is in hex format.
84 *
85 * @param transport the transport being created.
86 * @param vtable the subclass vtable.
87 * @param server_guid non-#NULL if this transport is on the server side of a connection
88 * @param address the address of the transport
89 * @returns #TRUE on success.
90 */
91 dbus_bool_t
_dbus_transport_init_base(DBusTransport * transport,const DBusTransportVTable * vtable,const DBusString * server_guid,const DBusString * address)92 _dbus_transport_init_base (DBusTransport *transport,
93 const DBusTransportVTable *vtable,
94 const DBusString *server_guid,
95 const DBusString *address)
96 {
97 DBusMessageLoader *loader;
98 DBusAuth *auth;
99 DBusCounter *counter;
100 char *address_copy;
101
102 loader = _dbus_message_loader_new ();
103 if (loader == NULL)
104 return FALSE;
105
106 if (server_guid)
107 auth = _dbus_auth_server_new (server_guid);
108 else
109 auth = _dbus_auth_client_new ();
110 if (auth == NULL)
111 {
112 _dbus_message_loader_unref (loader);
113 return FALSE;
114 }
115
116 counter = _dbus_counter_new ();
117 if (counter == NULL)
118 {
119 _dbus_auth_unref (auth);
120 _dbus_message_loader_unref (loader);
121 return FALSE;
122 }
123
124 if (server_guid)
125 {
126 _dbus_assert (address == NULL);
127 address_copy = NULL;
128 }
129 else
130 {
131 _dbus_assert (address != NULL);
132
133 if (!_dbus_string_copy_data (address, &address_copy))
134 {
135 _dbus_counter_unref (counter);
136 _dbus_auth_unref (auth);
137 _dbus_message_loader_unref (loader);
138 return FALSE;
139 }
140 }
141
142 transport->refcount = 1;
143 transport->vtable = vtable;
144 transport->loader = loader;
145 transport->auth = auth;
146 transport->live_messages_size = counter;
147 transport->authenticated = FALSE;
148 transport->disconnected = FALSE;
149 transport->is_server = (server_guid != NULL);
150 transport->send_credentials_pending = !transport->is_server;
151 transport->receive_credentials_pending = transport->is_server;
152 transport->address = address_copy;
153
154 transport->unix_user_function = NULL;
155 transport->unix_user_data = NULL;
156 transport->free_unix_user_data = NULL;
157
158 transport->expected_guid = NULL;
159
160 /* Try to default to something that won't totally hose the system,
161 * but doesn't impose too much of a limitation.
162 */
163 transport->max_live_messages_size = _DBUS_ONE_MEGABYTE * 63;
164
165 transport->credentials.pid = -1;
166 transport->credentials.uid = -1;
167 transport->credentials.gid = -1;
168
169 _dbus_counter_set_notify (transport->live_messages_size,
170 transport->max_live_messages_size,
171 live_messages_size_notify,
172 transport);
173
174 if (transport->address)
175 _dbus_verbose ("Initialized transport on address %s\n", transport->address);
176
177 return TRUE;
178 }
179
180 /**
181 * Finalizes base class members of DBusTransport.
182 * Chained up to from subclass finalizers.
183 *
184 * @param transport the transport.
185 */
186 void
_dbus_transport_finalize_base(DBusTransport * transport)187 _dbus_transport_finalize_base (DBusTransport *transport)
188 {
189 if (!transport->disconnected)
190 _dbus_transport_disconnect (transport);
191
192 if (transport->free_unix_user_data != NULL)
193 (* transport->free_unix_user_data) (transport->unix_user_data);
194
195 _dbus_message_loader_unref (transport->loader);
196 _dbus_auth_unref (transport->auth);
197 _dbus_counter_set_notify (transport->live_messages_size,
198 0, NULL, NULL);
199 _dbus_counter_unref (transport->live_messages_size);
200 dbus_free (transport->address);
201 dbus_free (transport->expected_guid);
202 }
203
204
205 /**
206 * Verifies if a given D-Bus address is a valid address
207 * by attempting to connect to it. If it is, returns the
208 * opened DBusTransport object. If it isn't, returns #NULL
209 * and sets @p error.
210 *
211 * @param error address where an error can be returned.
212 * @returns a new transport, or #NULL on failure.
213 */
214 static DBusTransport*
check_address(const char * address,DBusError * error)215 check_address (const char *address, DBusError *error)
216 {
217 DBusAddressEntry **entries;
218 DBusTransport *transport = NULL;
219 int len, i;
220
221 _dbus_assert (address != NULL);
222 _dbus_assert (*address != '\0');
223
224 if (!dbus_parse_address (address, &entries, &len, error))
225 return FALSE; /* not a valid address */
226
227 for (i = 0; i < len; i++)
228 {
229 transport = _dbus_transport_open (entries[i], error);
230 if (transport != NULL)
231 break;
232 }
233
234 dbus_address_entries_free (entries);
235 return transport;
236 }
237
238 /**
239 * Creates a new transport for the "autostart" method.
240 * This creates a client-side of a transport.
241 *
242 * @param error address where an error can be returned.
243 * @returns a new transport, or #NULL on failure.
244 */
245 static DBusTransport*
_dbus_transport_new_for_autolaunch(DBusError * error)246 _dbus_transport_new_for_autolaunch (DBusError *error)
247 {
248 DBusString address;
249 DBusTransport *result = NULL;
250
251 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
252
253 if (!_dbus_string_init (&address))
254 {
255 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
256 return NULL;
257 }
258
259 if (!_dbus_get_autolaunch_address (&address, error))
260 {
261 _DBUS_ASSERT_ERROR_IS_SET (error);
262 goto out;
263 }
264
265 result = check_address (_dbus_string_get_const_data (&address), error);
266 if (result == NULL)
267 _DBUS_ASSERT_ERROR_IS_SET (error);
268 else
269 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
270
271 out:
272 _dbus_string_free (&address);
273 return result;
274 }
275
276 static DBusTransportOpenResult
_dbus_transport_open_autolaunch(DBusAddressEntry * entry,DBusTransport ** transport_p,DBusError * error)277 _dbus_transport_open_autolaunch (DBusAddressEntry *entry,
278 DBusTransport **transport_p,
279 DBusError *error)
280 {
281 const char *method;
282
283 method = dbus_address_entry_get_method (entry);
284 _dbus_assert (method != NULL);
285
286 if (strcmp (method, "autolaunch") == 0)
287 {
288 *transport_p = _dbus_transport_new_for_autolaunch (error);
289
290 if (*transport_p == NULL)
291 {
292 _DBUS_ASSERT_ERROR_IS_SET (error);
293 return DBUS_TRANSPORT_OPEN_DID_NOT_CONNECT;
294 }
295 else
296 {
297 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
298 return DBUS_TRANSPORT_OPEN_OK;
299 }
300 }
301 else
302 {
303 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
304 return DBUS_TRANSPORT_OPEN_NOT_HANDLED;
305 }
306 }
307
308 static const struct {
309 DBusTransportOpenResult (* func) (DBusAddressEntry *entry,
310 DBusTransport **transport_p,
311 DBusError *error);
312 } open_funcs[] = {
313 { _dbus_transport_open_socket },
314 { _dbus_transport_open_platform_specific },
315 { _dbus_transport_open_autolaunch }
316 #ifdef DBUS_BUILD_TESTS
317 , { _dbus_transport_open_debug_pipe }
318 #endif
319 };
320
321 /**
322 * Try to open a new transport for the given address entry. (This
323 * opens a client-side-of-the-connection transport.)
324 *
325 * @param entry the address entry
326 * @param error location to store reason for failure.
327 * @returns new transport of #NULL on failure.
328 */
329 DBusTransport*
_dbus_transport_open(DBusAddressEntry * entry,DBusError * error)330 _dbus_transport_open (DBusAddressEntry *entry,
331 DBusError *error)
332 {
333 DBusTransport *transport;
334 const char *expected_guid_orig;
335 char *expected_guid;
336 int i;
337 DBusError tmp_error;
338
339 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
340
341 transport = NULL;
342 expected_guid_orig = dbus_address_entry_get_value (entry, "guid");
343 expected_guid = _dbus_strdup (expected_guid_orig);
344
345 if (expected_guid_orig != NULL && expected_guid == NULL)
346 {
347 _DBUS_SET_OOM (error);
348 return NULL;
349 }
350
351 dbus_error_init (&tmp_error);
352 for (i = 0; i < (int) _DBUS_N_ELEMENTS (open_funcs); ++i)
353 {
354 DBusTransportOpenResult result;
355
356 _DBUS_ASSERT_ERROR_IS_CLEAR (&tmp_error);
357 result = (* open_funcs[i].func) (entry, &transport, &tmp_error);
358
359 switch (result)
360 {
361 case DBUS_TRANSPORT_OPEN_OK:
362 _DBUS_ASSERT_ERROR_IS_CLEAR (&tmp_error);
363 goto out;
364 break;
365 case DBUS_TRANSPORT_OPEN_NOT_HANDLED:
366 _DBUS_ASSERT_ERROR_IS_CLEAR (&tmp_error);
367 /* keep going through the loop of open funcs */
368 break;
369 case DBUS_TRANSPORT_OPEN_BAD_ADDRESS:
370 _DBUS_ASSERT_ERROR_IS_SET (&tmp_error);
371 goto out;
372 break;
373 case DBUS_TRANSPORT_OPEN_DID_NOT_CONNECT:
374 _DBUS_ASSERT_ERROR_IS_SET (&tmp_error);
375 goto out;
376 break;
377 }
378 }
379
380 out:
381
382 if (transport == NULL)
383 {
384 if (!dbus_error_is_set (&tmp_error))
385 _dbus_set_bad_address (&tmp_error,
386 NULL, NULL,
387 "Unknown address type (examples of valid types are \"tcp\" and on UNIX \"unix\")");
388
389 _DBUS_ASSERT_ERROR_IS_SET (&tmp_error);
390 dbus_move_error(&tmp_error, error);
391 dbus_free (expected_guid);
392 }
393 else
394 {
395 _DBUS_ASSERT_ERROR_IS_CLEAR (&tmp_error);
396 transport->expected_guid = expected_guid;
397 }
398
399 return transport;
400 }
401
402 /**
403 * Increments the reference count for the transport.
404 *
405 * @param transport the transport.
406 * @returns the transport.
407 */
408 DBusTransport *
_dbus_transport_ref(DBusTransport * transport)409 _dbus_transport_ref (DBusTransport *transport)
410 {
411 _dbus_assert (transport->refcount > 0);
412
413 transport->refcount += 1;
414
415 return transport;
416 }
417
418 /**
419 * Decrements the reference count for the transport.
420 * Disconnects and finalizes the transport if
421 * the reference count reaches zero.
422 *
423 * @param transport the transport.
424 */
425 void
_dbus_transport_unref(DBusTransport * transport)426 _dbus_transport_unref (DBusTransport *transport)
427 {
428 _dbus_assert (transport != NULL);
429 _dbus_assert (transport->refcount > 0);
430
431 transport->refcount -= 1;
432 if (transport->refcount == 0)
433 {
434 _dbus_verbose ("%s: finalizing\n", _DBUS_FUNCTION_NAME);
435
436 _dbus_assert (transport->vtable->finalize != NULL);
437
438 (* transport->vtable->finalize) (transport);
439 }
440 }
441
442 /**
443 * Closes our end of the connection to a remote application. Further
444 * attempts to use this transport will fail. Only the first call to
445 * _dbus_transport_disconnect() will have an effect.
446 *
447 * @param transport the transport.
448 *
449 */
450 void
_dbus_transport_disconnect(DBusTransport * transport)451 _dbus_transport_disconnect (DBusTransport *transport)
452 {
453 _dbus_verbose ("%s start\n", _DBUS_FUNCTION_NAME);
454
455 _dbus_assert (transport->vtable->disconnect != NULL);
456
457 if (transport->disconnected)
458 return;
459
460 (* transport->vtable->disconnect) (transport);
461
462 transport->disconnected = TRUE;
463
464 _dbus_verbose ("%s end\n", _DBUS_FUNCTION_NAME);
465 }
466
467 /**
468 * Returns #TRUE if the transport has not been disconnected.
469 * Disconnection can result from _dbus_transport_disconnect()
470 * or because the server drops its end of the connection.
471 *
472 * @param transport the transport.
473 * @returns whether we're connected
474 */
475 dbus_bool_t
_dbus_transport_get_is_connected(DBusTransport * transport)476 _dbus_transport_get_is_connected (DBusTransport *transport)
477 {
478 return !transport->disconnected;
479 }
480
481 /**
482 * Returns #TRUE if we have been authenticated. Will return #TRUE
483 * even if the transport is disconnected.
484 *
485 * @todo we drop connection->mutex when calling the unix_user_function,
486 * which may not be safe really.
487 *
488 * @param transport the transport
489 * @returns whether we're authenticated
490 */
491 dbus_bool_t
_dbus_transport_get_is_authenticated(DBusTransport * transport)492 _dbus_transport_get_is_authenticated (DBusTransport *transport)
493 {
494 /* We don't want to run unix_user_function on Windows, but it
495 * can exist, which allows application code to just unconditionally
496 * set it and have it only be invoked when appropriate.
497 */
498 dbus_bool_t on_windows = FALSE;
499 #ifdef DBUS_WIN
500 on_windows = TRUE;
501 #endif
502
503 if (transport->authenticated)
504 return TRUE;
505 else
506 {
507 dbus_bool_t maybe_authenticated;
508
509 if (transport->disconnected)
510 return FALSE;
511
512 /* paranoia ref since we call user callbacks sometimes */
513 _dbus_connection_ref_unlocked (transport->connection);
514
515 maybe_authenticated =
516 (!(transport->send_credentials_pending ||
517 transport->receive_credentials_pending));
518
519 if (maybe_authenticated)
520 {
521 switch (_dbus_auth_do_work (transport->auth))
522 {
523 case DBUS_AUTH_STATE_AUTHENTICATED:
524 /* leave as maybe_authenticated */
525 break;
526 default:
527 maybe_authenticated = FALSE;
528 }
529 }
530
531 if (maybe_authenticated && !transport->is_server)
532 {
533 const char *server_guid;
534
535 server_guid = _dbus_auth_get_guid_from_server (transport->auth);
536 _dbus_assert (server_guid != NULL);
537
538 if (transport->expected_guid &&
539 strcmp (transport->expected_guid, server_guid) != 0)
540 {
541 _dbus_verbose ("Client expected GUID '%s' and we got '%s' from the server\n",
542 transport->expected_guid, server_guid);
543 _dbus_transport_disconnect (transport);
544 _dbus_connection_unref_unlocked (transport->connection);
545 return FALSE;
546 }
547
548 if (transport->expected_guid == NULL)
549 {
550 transport->expected_guid = _dbus_strdup (server_guid);
551
552 if (transport->expected_guid == NULL)
553 {
554 _dbus_verbose ("No memory to complete auth in %s\n", _DBUS_FUNCTION_NAME);
555 return FALSE;
556 }
557 }
558 }
559
560 /* If we've authenticated as some identity, check that the auth
561 * identity is the same as our own identity. In the future, we
562 * may have API allowing applications to specify how this is
563 * done, for example they may allow connection as any identity,
564 * but then impose restrictions on certain identities.
565 * Or they may give certain identities extra privileges.
566 */
567
568 if (maybe_authenticated && transport->is_server)
569 {
570 DBusCredentials auth_identity;
571
572 _dbus_auth_get_identity (transport->auth, &auth_identity);
573
574 if (transport->unix_user_function != NULL && !on_windows)
575 {
576 dbus_bool_t allow;
577 DBusConnection *connection;
578 DBusAllowUnixUserFunction unix_user_function;
579 void *unix_user_data;
580
581 /* Dropping the lock here probably isn't that safe. */
582
583 connection = transport->connection;
584 unix_user_function = transport->unix_user_function;
585 unix_user_data = transport->unix_user_data;
586
587 _dbus_verbose ("unlock %s\n", _DBUS_FUNCTION_NAME);
588 _dbus_connection_unlock (connection);
589
590 allow = (* unix_user_function) (connection,
591 auth_identity.uid,
592 unix_user_data);
593
594 _dbus_verbose ("lock %s post unix user function\n", _DBUS_FUNCTION_NAME);
595 _dbus_connection_lock (connection);
596
597 if (allow)
598 {
599 _dbus_verbose ("Client UID "DBUS_UID_FORMAT" authorized\n", auth_identity.uid);
600 }
601 else
602 {
603 _dbus_verbose ("Client UID "DBUS_UID_FORMAT
604 " was rejected, disconnecting\n",
605 auth_identity.uid);
606 _dbus_transport_disconnect (transport);
607 _dbus_connection_unref_unlocked (connection);
608 return FALSE;
609 }
610 }
611 else
612 {
613 DBusCredentials our_identity;
614
615 _dbus_credentials_from_current_process (&our_identity);
616
617 if (!_dbus_credentials_match (&our_identity,
618 &auth_identity))
619 {
620 _dbus_verbose ("Client authorized as UID "DBUS_UID_FORMAT
621 " but our UID is "DBUS_UID_FORMAT", disconnecting\n",
622 auth_identity.uid, our_identity.uid);
623 _dbus_transport_disconnect (transport);
624 _dbus_connection_unref_unlocked (transport->connection);
625 return FALSE;
626 }
627 else
628 {
629 _dbus_verbose ("Client authorized as UID "DBUS_UID_FORMAT
630 " matching our UID "DBUS_UID_FORMAT"\n",
631 auth_identity.uid, our_identity.uid);
632 }
633 }
634 }
635
636 transport->authenticated = maybe_authenticated;
637
638 _dbus_connection_unref_unlocked (transport->connection);
639 return maybe_authenticated;
640 }
641 }
642
643 /**
644 * Gets the address of a transport. It will be
645 * #NULL for a server-side transport.
646 *
647 * @param transport the transport
648 * @returns transport's address
649 */
650 const char*
_dbus_transport_get_address(DBusTransport * transport)651 _dbus_transport_get_address (DBusTransport *transport)
652 {
653 return transport->address;
654 }
655
656 /**
657 * Handles a watch by reading data, writing data, or disconnecting
658 * the transport, as appropriate for the given condition.
659 *
660 * @param transport the transport.
661 * @param watch the watch.
662 * @param condition the current state of the watched file descriptor.
663 * @returns #FALSE if not enough memory to fully handle the watch
664 */
665 dbus_bool_t
_dbus_transport_handle_watch(DBusTransport * transport,DBusWatch * watch,unsigned int condition)666 _dbus_transport_handle_watch (DBusTransport *transport,
667 DBusWatch *watch,
668 unsigned int condition)
669 {
670 dbus_bool_t retval;
671
672 _dbus_assert (transport->vtable->handle_watch != NULL);
673
674 if (transport->disconnected)
675 return TRUE;
676
677 if (dbus_watch_get_fd (watch) < 0)
678 {
679 _dbus_warn_check_failed ("Tried to handle an invalidated watch; this watch should have been removed\n");
680 return TRUE;
681 }
682
683 _dbus_watch_sanitize_condition (watch, &condition);
684
685 _dbus_transport_ref (transport);
686 _dbus_watch_ref (watch);
687 retval = (* transport->vtable->handle_watch) (transport, watch, condition);
688 _dbus_watch_unref (watch);
689 _dbus_transport_unref (transport);
690
691 return retval;
692 }
693
694 /**
695 * Sets the connection using this transport. Allows the transport
696 * to add watches to the connection, queue incoming messages,
697 * and pull outgoing messages.
698 *
699 * @param transport the transport.
700 * @param connection the connection.
701 * @returns #FALSE if not enough memory
702 */
703 dbus_bool_t
_dbus_transport_set_connection(DBusTransport * transport,DBusConnection * connection)704 _dbus_transport_set_connection (DBusTransport *transport,
705 DBusConnection *connection)
706 {
707 _dbus_assert (transport->vtable->connection_set != NULL);
708 _dbus_assert (transport->connection == NULL);
709
710 transport->connection = connection;
711
712 _dbus_transport_ref (transport);
713 if (!(* transport->vtable->connection_set) (transport))
714 transport->connection = NULL;
715 _dbus_transport_unref (transport);
716
717 return transport->connection != NULL;
718 }
719
720 /**
721 * Get the socket file descriptor, if any.
722 *
723 * @param transport the transport
724 * @param fd_p pointer to fill in with the descriptor
725 * @returns #TRUE if a descriptor was available
726 */
727 dbus_bool_t
_dbus_transport_get_socket_fd(DBusTransport * transport,int * fd_p)728 _dbus_transport_get_socket_fd (DBusTransport *transport,
729 int *fd_p)
730 {
731 dbus_bool_t retval;
732
733 if (transport->vtable->get_socket_fd == NULL)
734 return FALSE;
735
736 if (transport->disconnected)
737 return FALSE;
738
739 _dbus_transport_ref (transport);
740
741 retval = (* transport->vtable->get_socket_fd) (transport,
742 fd_p);
743
744 _dbus_transport_unref (transport);
745
746 return retval;
747 }
748
749 /**
750 * Performs a single poll()/select() on the transport's file
751 * descriptors and then reads/writes data as appropriate,
752 * queueing incoming messages and sending outgoing messages.
753 * This is the backend for _dbus_connection_do_iteration().
754 * See _dbus_connection_do_iteration() for full details.
755 *
756 * @param transport the transport.
757 * @param flags indicates whether to read or write, and whether to block.
758 * @param timeout_milliseconds if blocking, timeout or -1 for no timeout.
759 */
760 void
_dbus_transport_do_iteration(DBusTransport * transport,unsigned int flags,int timeout_milliseconds)761 _dbus_transport_do_iteration (DBusTransport *transport,
762 unsigned int flags,
763 int timeout_milliseconds)
764 {
765 _dbus_assert (transport->vtable->do_iteration != NULL);
766
767 _dbus_verbose ("Transport iteration flags 0x%x timeout %d connected = %d\n",
768 flags, timeout_milliseconds, !transport->disconnected);
769
770 if ((flags & (DBUS_ITERATION_DO_WRITING |
771 DBUS_ITERATION_DO_READING)) == 0)
772 return; /* Nothing to do */
773
774 if (transport->disconnected)
775 return;
776
777 _dbus_transport_ref (transport);
778 (* transport->vtable->do_iteration) (transport, flags,
779 timeout_milliseconds);
780 _dbus_transport_unref (transport);
781
782 _dbus_verbose ("%s end\n", _DBUS_FUNCTION_NAME);
783 }
784
785 static dbus_bool_t
recover_unused_bytes(DBusTransport * transport)786 recover_unused_bytes (DBusTransport *transport)
787 {
788 if (_dbus_auth_needs_decoding (transport->auth))
789 {
790 DBusString plaintext;
791 const DBusString *encoded;
792 DBusString *buffer;
793 int orig_len;
794
795 if (!_dbus_string_init (&plaintext))
796 goto nomem;
797
798 _dbus_auth_get_unused_bytes (transport->auth,
799 &encoded);
800
801 if (!_dbus_auth_decode_data (transport->auth,
802 encoded, &plaintext))
803 {
804 _dbus_string_free (&plaintext);
805 goto nomem;
806 }
807
808 _dbus_message_loader_get_buffer (transport->loader,
809 &buffer);
810
811 orig_len = _dbus_string_get_length (buffer);
812
813 if (!_dbus_string_move (&plaintext, 0, buffer,
814 orig_len))
815 {
816 _dbus_string_free (&plaintext);
817 goto nomem;
818 }
819
820 _dbus_verbose (" %d unused bytes sent to message loader\n",
821 _dbus_string_get_length (buffer) -
822 orig_len);
823
824 _dbus_message_loader_return_buffer (transport->loader,
825 buffer,
826 _dbus_string_get_length (buffer) -
827 orig_len);
828
829 _dbus_auth_delete_unused_bytes (transport->auth);
830
831 _dbus_string_free (&plaintext);
832 }
833 else
834 {
835 const DBusString *bytes;
836 DBusString *buffer;
837 int orig_len;
838 dbus_bool_t succeeded;
839
840 _dbus_message_loader_get_buffer (transport->loader,
841 &buffer);
842
843 orig_len = _dbus_string_get_length (buffer);
844
845 _dbus_auth_get_unused_bytes (transport->auth,
846 &bytes);
847
848 succeeded = TRUE;
849 if (!_dbus_string_copy (bytes, 0, buffer, _dbus_string_get_length (buffer)))
850 succeeded = FALSE;
851
852 _dbus_verbose (" %d unused bytes sent to message loader\n",
853 _dbus_string_get_length (buffer) -
854 orig_len);
855
856 _dbus_message_loader_return_buffer (transport->loader,
857 buffer,
858 _dbus_string_get_length (buffer) -
859 orig_len);
860
861 if (succeeded)
862 _dbus_auth_delete_unused_bytes (transport->auth);
863 else
864 goto nomem;
865 }
866
867 return TRUE;
868
869 nomem:
870 _dbus_verbose ("Not enough memory to transfer unused bytes from auth conversation\n");
871 return FALSE;
872 }
873
874 /**
875 * Reports our current dispatch status (whether there's buffered
876 * data to be queued as messages, or not, or we need memory).
877 *
878 * @param transport the transport
879 * @returns current status
880 */
881 DBusDispatchStatus
_dbus_transport_get_dispatch_status(DBusTransport * transport)882 _dbus_transport_get_dispatch_status (DBusTransport *transport)
883 {
884 if (_dbus_counter_get_value (transport->live_messages_size) >= transport->max_live_messages_size)
885 return DBUS_DISPATCH_COMPLETE; /* complete for now */
886
887 if (!_dbus_transport_get_is_authenticated (transport))
888 {
889 if (_dbus_auth_do_work (transport->auth) ==
890 DBUS_AUTH_STATE_WAITING_FOR_MEMORY)
891 return DBUS_DISPATCH_NEED_MEMORY;
892 else if (!_dbus_transport_get_is_authenticated (transport))
893 return DBUS_DISPATCH_COMPLETE;
894 }
895
896 if (!transport->unused_bytes_recovered &&
897 !recover_unused_bytes (transport))
898 return DBUS_DISPATCH_NEED_MEMORY;
899
900 transport->unused_bytes_recovered = TRUE;
901
902 if (!_dbus_message_loader_queue_messages (transport->loader))
903 return DBUS_DISPATCH_NEED_MEMORY;
904
905 if (_dbus_message_loader_peek_message (transport->loader) != NULL)
906 return DBUS_DISPATCH_DATA_REMAINS;
907 else
908 return DBUS_DISPATCH_COMPLETE;
909 }
910
911 /**
912 * Processes data we've read while handling a watch, potentially
913 * converting some of it to messages and queueing those messages on
914 * the connection.
915 *
916 * @param transport the transport
917 * @returns #TRUE if we had enough memory to queue all messages
918 */
919 dbus_bool_t
_dbus_transport_queue_messages(DBusTransport * transport)920 _dbus_transport_queue_messages (DBusTransport *transport)
921 {
922 DBusDispatchStatus status;
923
924 #if 0
925 _dbus_verbose ("_dbus_transport_queue_messages()\n");
926 #endif
927
928 /* Queue any messages */
929 while ((status = _dbus_transport_get_dispatch_status (transport)) == DBUS_DISPATCH_DATA_REMAINS)
930 {
931 DBusMessage *message;
932 DBusList *link;
933
934 link = _dbus_message_loader_pop_message_link (transport->loader);
935 _dbus_assert (link != NULL);
936
937 message = link->data;
938
939 _dbus_verbose ("queueing received message %p\n", message);
940
941 if (!_dbus_message_add_size_counter (message, transport->live_messages_size))
942 {
943 _dbus_message_loader_putback_message_link (transport->loader,
944 link);
945 status = DBUS_DISPATCH_NEED_MEMORY;
946 break;
947 }
948 else
949 {
950 /* pass ownership of link and message ref to connection */
951 _dbus_connection_queue_received_message_link (transport->connection,
952 link);
953 }
954 }
955
956 if (_dbus_message_loader_get_is_corrupted (transport->loader))
957 {
958 _dbus_verbose ("Corrupted message stream, disconnecting\n");
959 _dbus_transport_disconnect (transport);
960 }
961
962 return status != DBUS_DISPATCH_NEED_MEMORY;
963 }
964
965 /**
966 * See dbus_connection_set_max_message_size().
967 *
968 * @param transport the transport
969 * @param size the max size of a single message
970 */
971 void
_dbus_transport_set_max_message_size(DBusTransport * transport,long size)972 _dbus_transport_set_max_message_size (DBusTransport *transport,
973 long size)
974 {
975 _dbus_message_loader_set_max_message_size (transport->loader, size);
976 }
977
978 /**
979 * See dbus_connection_get_max_message_size().
980 *
981 * @param transport the transport
982 * @returns max message size
983 */
984 long
_dbus_transport_get_max_message_size(DBusTransport * transport)985 _dbus_transport_get_max_message_size (DBusTransport *transport)
986 {
987 return _dbus_message_loader_get_max_message_size (transport->loader);
988 }
989
990 /**
991 * See dbus_connection_set_max_received_size().
992 *
993 * @param transport the transport
994 * @param size the max size of all incoming messages
995 */
996 void
_dbus_transport_set_max_received_size(DBusTransport * transport,long size)997 _dbus_transport_set_max_received_size (DBusTransport *transport,
998 long size)
999 {
1000 transport->max_live_messages_size = size;
1001 _dbus_counter_set_notify (transport->live_messages_size,
1002 transport->max_live_messages_size,
1003 live_messages_size_notify,
1004 transport);
1005 }
1006
1007
1008 /**
1009 * See dbus_connection_get_max_received_size().
1010 *
1011 * @param transport the transport
1012 * @returns max bytes for all live messages
1013 */
1014 long
_dbus_transport_get_max_received_size(DBusTransport * transport)1015 _dbus_transport_get_max_received_size (DBusTransport *transport)
1016 {
1017 return transport->max_live_messages_size;
1018 }
1019
1020 /**
1021 * See dbus_connection_get_unix_user().
1022 *
1023 * @param transport the transport
1024 * @param uid return location for the user ID
1025 * @returns #TRUE if uid is filled in with a valid user ID
1026 */
1027 dbus_bool_t
_dbus_transport_get_unix_user(DBusTransport * transport,unsigned long * uid)1028 _dbus_transport_get_unix_user (DBusTransport *transport,
1029 unsigned long *uid)
1030 {
1031 DBusCredentials auth_identity;
1032
1033 *uid = _DBUS_INT32_MAX; /* better than some root or system user in
1034 * case of bugs in the caller. Caller should
1035 * never use this value on purpose, however.
1036 */
1037
1038 if (!transport->authenticated)
1039 return FALSE;
1040
1041 _dbus_auth_get_identity (transport->auth, &auth_identity);
1042
1043 if (auth_identity.uid != DBUS_UID_UNSET)
1044 {
1045 *uid = auth_identity.uid;
1046 return TRUE;
1047 }
1048 else
1049 return FALSE;
1050 }
1051
1052 /**
1053 * See dbus_connection_get_unix_process_id().
1054 *
1055 * @param transport the transport
1056 * @param pid return location for the process ID
1057 * @returns #TRUE if uid is filled in with a valid process ID
1058 */
1059 dbus_bool_t
_dbus_transport_get_unix_process_id(DBusTransport * transport,unsigned long * pid)1060 _dbus_transport_get_unix_process_id (DBusTransport *transport,
1061 unsigned long *pid)
1062 {
1063 DBusCredentials auth_identity;
1064
1065 *pid = DBUS_PID_UNSET; /* Caller should never use this value on purpose,
1066 * but we set it to a safe number, INT_MAX,
1067 * just to root out possible bugs in bad callers.
1068 */
1069
1070 if (!transport->authenticated)
1071 return FALSE;
1072
1073 _dbus_auth_get_identity (transport->auth, &auth_identity);
1074
1075 if (auth_identity.pid != DBUS_PID_UNSET)
1076 {
1077 *pid = auth_identity.pid;
1078 return TRUE;
1079 }
1080 else
1081 return FALSE;
1082 }
1083
1084 /**
1085 * See dbus_connection_set_unix_user_function().
1086 *
1087 * @param transport the transport
1088 * @param function the predicate
1089 * @param data data to pass to the predicate
1090 * @param free_data_function function to free the data
1091 * @param old_data the old user data to be freed
1092 * @param old_free_data_function old free data function to free it with
1093 */
1094 void
_dbus_transport_set_unix_user_function(DBusTransport * transport,DBusAllowUnixUserFunction function,void * data,DBusFreeFunction free_data_function,void ** old_data,DBusFreeFunction * old_free_data_function)1095 _dbus_transport_set_unix_user_function (DBusTransport *transport,
1096 DBusAllowUnixUserFunction function,
1097 void *data,
1098 DBusFreeFunction free_data_function,
1099 void **old_data,
1100 DBusFreeFunction *old_free_data_function)
1101 {
1102 *old_data = transport->unix_user_data;
1103 *old_free_data_function = transport->free_unix_user_data;
1104
1105 transport->unix_user_function = function;
1106 transport->unix_user_data = data;
1107 transport->free_unix_user_data = free_data_function;
1108 }
1109
1110 /**
1111 * Sets the SASL authentication mechanisms supported by this transport.
1112 *
1113 * @param transport the transport
1114 * @param mechanisms the #NULL-terminated array of mechanisms
1115 *
1116 * @returns #FALSE if no memory
1117 */
1118 dbus_bool_t
_dbus_transport_set_auth_mechanisms(DBusTransport * transport,const char ** mechanisms)1119 _dbus_transport_set_auth_mechanisms (DBusTransport *transport,
1120 const char **mechanisms)
1121 {
1122 return _dbus_auth_set_mechanisms (transport->auth, mechanisms);
1123 }
1124
1125
1126 /** @} */
1127