1 /* -*- mode: C; c-file-style: "gnu" -*- */
2 /* dbus-transport.c DBusTransport object (internal to D-BUS implementation)
4 * Copyright (C) 2002, 2003 Red Hat Inc.
6 * Licensed under the Academic Free License version 1.2
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.
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.
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
24 #include "dbus-transport-protected.h"
25 #include "dbus-transport-unix.h"
26 #include "dbus-connection-internal.h"
27 #include "dbus-watch.h"
28 #include "dbus-auth.h"
31 * @defgroup DBusTransport DBusTransport object
32 * @ingroup DBusInternals
33 * @brief "Backend" for a DBusConnection.
35 * Types and functions related to DBusTransport. A transport is an
36 * abstraction that can send and receive data via various kinds of
37 * network connections or other IPC mechanisms.
43 * @typedef DBusTransport
45 * Opaque object representing a way message stream.
46 * DBusTransport abstracts various kinds of actual
47 * transport mechanism, such as different network protocols,
48 * or encryption schemes.
52 * Refs a transport and associated connection for reentrancy.
54 * @todo this macro reflects a design mistake, which is that the
55 * transport has a pointer to its connection. Ownership should move in
56 * only one direction; the connection should push/pull from the
57 * transport, rather than vice versa. Then the connection would take
58 * care of referencing itself when needed.
60 #define DBUS_TRANSPORT_HOLD_REF(t) \
61 _dbus_transport_ref (t); if ((t)->connection) dbus_connection_ref ((t)->connection)
64 * Inverse of DBUS_TRANSPORT_HOLD_REF().
66 #define DBUS_TRANSPORT_RELEASE_REF(t) \
67 if ((t)->connection) dbus_connection_unref ((t)->connection); _dbus_transport_unref (t)
70 live_messages_size_notify (DBusCounter *counter,
73 DBusTransport *transport = user_data;
75 DBUS_TRANSPORT_HOLD_REF (transport);
78 _dbus_verbose ("Counter value is now %d\n",
79 (int) _dbus_counter_get_value (counter));
82 /* disable or re-enable the read watch for the transport if
85 if (* transport->vtable->live_messages_changed)
86 (* transport->vtable->live_messages_changed) (transport);
88 DBUS_TRANSPORT_RELEASE_REF (transport);
92 * Initializes the base class members of DBusTransport.
93 * Chained up to by subclasses in their constructor.
95 * @param transport the transport being created.
96 * @param vtable the subclass vtable.
97 * @param server #TRUE if this transport is on the server side of a connection
98 * @returns #TRUE on success.
101 _dbus_transport_init_base (DBusTransport *transport,
102 const DBusTransportVTable *vtable,
105 DBusMessageLoader *loader;
107 DBusCounter *counter;
109 loader = _dbus_message_loader_new ();
114 auth = _dbus_auth_server_new ();
116 auth = _dbus_auth_client_new ();
119 _dbus_message_loader_unref (loader);
123 counter = _dbus_counter_new ();
126 _dbus_auth_unref (auth);
127 _dbus_message_loader_unref (loader);
131 transport->refcount = 1;
132 transport->vtable = vtable;
133 transport->loader = loader;
134 transport->auth = auth;
135 transport->live_messages_size = counter;
136 transport->authenticated = FALSE;
137 transport->messages_need_sending = FALSE;
138 transport->disconnected = FALSE;
139 transport->send_credentials_pending = !server;
140 transport->receive_credentials_pending = server;
141 transport->is_server = server;
143 /* Try to default to something that won't totally hose the system,
144 * but doesn't impose too much of a limitation.
146 transport->max_live_messages_size = _DBUS_ONE_MEGABYTE * 63;
148 transport->credentials.pid = -1;
149 transport->credentials.uid = -1;
150 transport->credentials.gid = -1;
152 _dbus_counter_set_notify (transport->live_messages_size,
153 transport->max_live_messages_size,
154 live_messages_size_notify,
161 * Finalizes base class members of DBusTransport.
162 * Chained up to from subclass finalizers.
164 * @param transport the transport.
167 _dbus_transport_finalize_base (DBusTransport *transport)
169 if (!transport->disconnected)
170 _dbus_transport_disconnect (transport);
172 _dbus_message_loader_unref (transport->loader);
173 _dbus_auth_unref (transport->auth);
174 _dbus_counter_set_notify (transport->live_messages_size,
176 _dbus_counter_unref (transport->live_messages_size);
180 * Opens a new transport for the given address. (This opens a
181 * client-side-of-the-connection transport.)
183 * @todo right now the address is just a Unix domain socket path.
185 * @param address the address.
186 * @param result location to store reason for failure.
187 * @returns new transport of #NULL on failure.
190 _dbus_transport_open (const char *address,
191 DBusResultCode *result)
193 DBusTransport *transport;
195 /* FIXME parse the address - whatever format
196 * we decide addresses are in - and find the
197 * appropriate transport.
200 /* Pretend it's just a unix domain socket name for now */
201 transport = _dbus_transport_new_for_domain_socket (address,
209 * Increments the reference count for the transport.
211 * @param transport the transport.
214 _dbus_transport_ref (DBusTransport *transport)
216 transport->refcount += 1;
220 * Decrements the reference count for the transport.
221 * Disconnects and finalizes the transport if
222 * the reference count reaches zero.
224 * @param transport the transport.
227 _dbus_transport_unref (DBusTransport *transport)
229 _dbus_assert (transport != NULL);
230 _dbus_assert (transport->refcount > 0);
232 transport->refcount -= 1;
233 if (transport->refcount == 0)
235 _dbus_assert (transport->vtable->finalize != NULL);
237 (* transport->vtable->finalize) (transport);
242 * Closes our end of the connection to a remote application. Further
243 * attempts to use this transport will fail. Only the first call to
244 * _dbus_transport_disconnect() will have an effect.
246 * @param transport the transport.
250 _dbus_transport_disconnect (DBusTransport *transport)
252 _dbus_assert (transport->vtable->disconnect != NULL);
254 if (transport->disconnected)
257 DBUS_TRANSPORT_HOLD_REF (transport);
258 (* transport->vtable->disconnect) (transport);
260 transport->disconnected = TRUE;
262 _dbus_connection_notify_disconnected (transport->connection);
264 DBUS_TRANSPORT_RELEASE_REF (transport);
268 * Returns #TRUE if the transport has not been disconnected.
269 * Disconnection can result from _dbus_transport_disconnect()
270 * or because the server drops its end of the connection.
272 * @param transport the transport.
273 * @returns whether we're connected
276 _dbus_transport_get_is_connected (DBusTransport *transport)
278 return !transport->disconnected;
282 * Returns #TRUE if we have been authenticated. Will return #TRUE
283 * even if the transport is disconnected.
285 * @param transport the transport
286 * @returns whether we're authenticated
289 _dbus_transport_get_is_authenticated (DBusTransport *transport)
291 if (transport->authenticated)
295 if (transport->disconnected)
298 transport->authenticated =
299 (!(transport->send_credentials_pending ||
300 transport->receive_credentials_pending)) &&
301 _dbus_auth_do_work (transport->auth) == DBUS_AUTH_STATE_AUTHENTICATED;
303 /* If we've authenticated as some identity, check that the auth
304 * identity is the same as our own identity. In the future, we
305 * may have API allowing applications to specify how this is
306 * done, for example they may allow connection as any identity,
307 * but then impose restrictions on certain identities.
308 * Or they may give certain identities extra privileges.
311 if (transport->authenticated && transport->is_server)
313 DBusCredentials auth_identity;
314 DBusCredentials our_identity;
316 _dbus_credentials_from_current_process (&our_identity);
317 _dbus_auth_get_identity (transport->auth, &auth_identity);
319 if (!_dbus_credentials_match (&our_identity,
322 _dbus_verbose ("Client authorized as UID %d but our UID is %d, disconnecting\n",
323 auth_identity.uid, our_identity.uid);
324 _dbus_transport_disconnect (transport);
329 _dbus_verbose ("Client authorized as UID %d matching our UID %d\n",
330 auth_identity.uid, our_identity.uid);
334 return transport->authenticated;
339 * Handles a watch by reading data, writing data, or disconnecting
340 * the transport, as appropriate for the given condition.
342 * @param transport the transport.
343 * @param watch the watch.
344 * @param condition the current state of the watched file descriptor.
347 _dbus_transport_handle_watch (DBusTransport *transport,
349 unsigned int condition)
351 _dbus_assert (transport->vtable->handle_watch != NULL);
353 if (transport->disconnected)
356 if (dbus_watch_get_fd (watch) < 0)
358 _dbus_warn ("Tried to handle an invalidated watch; this watch should have been removed\n");
362 _dbus_watch_sanitize_condition (watch, &condition);
364 DBUS_TRANSPORT_HOLD_REF (transport);
365 _dbus_watch_ref (watch);
366 (* transport->vtable->handle_watch) (transport, watch, condition);
367 _dbus_watch_unref (watch);
368 DBUS_TRANSPORT_RELEASE_REF (transport);
372 * Sets the connection using this transport. Allows the transport
373 * to add watches to the connection, queue incoming messages,
374 * and pull outgoing messages.
376 * @param transport the transport.
377 * @param connection the connection.
380 _dbus_transport_set_connection (DBusTransport *transport,
381 DBusConnection *connection)
383 _dbus_assert (transport->vtable->connection_set != NULL);
384 _dbus_assert (transport->connection == NULL);
386 transport->connection = connection;
388 DBUS_TRANSPORT_HOLD_REF (transport);
389 (* transport->vtable->connection_set) (transport);
390 DBUS_TRANSPORT_RELEASE_REF (transport);
394 * Notifies the transport when the outgoing message queue goes from
395 * empty to non-empty or vice versa. Typically causes the transport to
396 * add or remove its DBUS_WATCH_WRITABLE watch.
398 * @param transport the transport.
399 * @param queue_length the length of the outgoing message queue.
403 _dbus_transport_messages_pending (DBusTransport *transport,
406 _dbus_assert (transport->vtable->messages_pending != NULL);
408 if (transport->disconnected)
411 transport->messages_need_sending = queue_length > 0;
413 DBUS_TRANSPORT_HOLD_REF (transport);
414 (* transport->vtable->messages_pending) (transport,
416 DBUS_TRANSPORT_RELEASE_REF (transport);
420 * Performs a single poll()/select() on the transport's file
421 * descriptors and then reads/writes data as appropriate,
422 * queueing incoming messages and sending outgoing messages.
423 * This is the backend for _dbus_connection_do_iteration().
424 * See _dbus_connection_do_iteration() for full details.
426 * @param transport the transport.
427 * @param flags indicates whether to read or write, and whether to block.
428 * @param timeout_milliseconds if blocking, timeout or -1 for no timeout.
431 _dbus_transport_do_iteration (DBusTransport *transport,
433 int timeout_milliseconds)
435 _dbus_assert (transport->vtable->do_iteration != NULL);
437 if ((flags & (DBUS_ITERATION_DO_WRITING |
438 DBUS_ITERATION_DO_READING)) == 0)
439 return; /* Nothing to do */
441 if (transport->disconnected)
444 DBUS_TRANSPORT_HOLD_REF (transport);
445 (* transport->vtable->do_iteration) (transport, flags,
446 timeout_milliseconds);
447 DBUS_TRANSPORT_RELEASE_REF (transport);
451 * See dbus_connection_set_max_message_size().
453 * @param transport the transport
454 * @param size the max size of a single message
457 _dbus_transport_set_max_message_size (DBusTransport *transport,
460 _dbus_message_loader_set_max_message_size (transport->loader, size);
464 * See dbus_connection_get_max_message_size().
466 * @param transport the transport
467 * @returns max message size
470 _dbus_transport_get_max_message_size (DBusTransport *transport)
472 return _dbus_message_loader_get_max_message_size (transport->loader);
476 * See dbus_connection_set_max_live_messages_size().
478 * @param transport the transport
479 * @param size the max size of all incoming messages
482 _dbus_transport_set_max_live_messages_size (DBusTransport *transport,
485 transport->max_live_messages_size = size;
486 _dbus_counter_set_notify (transport->live_messages_size,
487 transport->max_live_messages_size,
488 live_messages_size_notify,
494 * See dbus_connection_get_max_live_messages_size().
496 * @param transport the transport
497 * @returns max bytes for all live messages
500 _dbus_transport_get_max_live_messages_size (DBusTransport *transport)
502 return transport->max_live_messages_size;