1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
2 /* dbus-transport-socket.c Socket subclasses of DBusTransport
4 * Copyright (C) 2002, 2003, 2004, 2006 Red Hat Inc.
6 * Licensed under the Academic Free License version 2.1
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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 #include "dbus-internals.h"
26 #include "dbus-connection-internal.h"
27 #include "dbus-nonce.h"
28 #include "dbus-transport-socket.h"
29 #include "dbus-transport-protected.h"
30 #include "dbus-watch.h"
31 #include "dbus-credentials.h"
34 * @defgroup DBusTransportSocket DBusTransport implementations for sockets
35 * @ingroup DBusInternals
36 * @brief Implementation details of DBusTransport on sockets
42 * Opaque object representing a socket file descriptor transport.
44 typedef struct DBusTransportSocket DBusTransportSocket;
47 * Implementation details of DBusTransportSocket. All members are private.
49 struct DBusTransportSocket
51 DBusTransport base; /**< Parent instance */
52 DBusSocket fd; /**< File descriptor. */
53 DBusWatch *read_watch; /**< Watch for readability. */
54 DBusWatch *write_watch; /**< Watch for writability. */
56 int max_bytes_read_per_iteration; /**< To avoid blocking too long. */
57 int max_bytes_written_per_iteration; /**< To avoid blocking too long. */
59 int message_bytes_written; /**< Number of bytes of current
60 * outgoing message that have
63 DBusString encoded_outgoing; /**< Encoded version of current
66 DBusString encoded_incoming; /**< Encoded version of current
72 free_watches (DBusTransport *transport)
74 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
76 _dbus_verbose ("start\n");
78 if (socket_transport->read_watch)
80 if (transport->connection)
81 _dbus_connection_remove_watch_unlocked (transport->connection,
82 socket_transport->read_watch);
83 _dbus_watch_invalidate (socket_transport->read_watch);
84 _dbus_watch_unref (socket_transport->read_watch);
85 socket_transport->read_watch = NULL;
88 if (socket_transport->write_watch)
90 if (transport->connection)
91 _dbus_connection_remove_watch_unlocked (transport->connection,
92 socket_transport->write_watch);
93 _dbus_watch_invalidate (socket_transport->write_watch);
94 _dbus_watch_unref (socket_transport->write_watch);
95 socket_transport->write_watch = NULL;
98 _dbus_verbose ("end\n");
102 socket_finalize (DBusTransport *transport)
104 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
106 _dbus_verbose ("\n");
108 free_watches (transport);
110 _dbus_string_free (&socket_transport->encoded_outgoing);
111 _dbus_string_free (&socket_transport->encoded_incoming);
113 _dbus_transport_finalize_base (transport);
115 _dbus_assert (socket_transport->read_watch == NULL);
116 _dbus_assert (socket_transport->write_watch == NULL);
118 dbus_free (transport);
122 check_write_watch (DBusTransport *transport)
124 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
127 if (transport->connection == NULL)
130 if (transport->disconnected)
132 _dbus_assert (socket_transport->write_watch == NULL);
136 _dbus_transport_ref (transport);
138 if (_dbus_transport_try_to_authenticate (transport))
139 needed = _dbus_connection_has_messages_to_send_unlocked (transport->connection);
142 if (transport->send_credentials_pending)
146 DBusAuthState auth_state;
148 auth_state = _dbus_auth_do_work (transport->auth);
150 /* If we need memory we install the write watch just in case,
151 * if there's no need for it, it will get de-installed
152 * next time we try reading.
154 if (auth_state == DBUS_AUTH_STATE_HAVE_BYTES_TO_SEND ||
155 auth_state == DBUS_AUTH_STATE_WAITING_FOR_MEMORY)
162 _dbus_verbose ("check_write_watch(): needed = %d on connection %p watch %p fd = %" DBUS_SOCKET_FORMAT " outgoing messages exist %d\n",
163 needed, transport->connection, socket_transport->write_watch,
164 _dbus_socket_printable (socket_transport->fd),
165 _dbus_connection_has_messages_to_send_unlocked (transport->connection));
167 _dbus_connection_toggle_watch_unlocked (transport->connection,
168 socket_transport->write_watch,
171 _dbus_transport_unref (transport);
175 check_read_watch (DBusTransport *transport)
177 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
178 dbus_bool_t need_read_watch;
180 _dbus_verbose ("fd = %" DBUS_SOCKET_FORMAT "\n",
181 _dbus_socket_printable (socket_transport->fd));
183 if (transport->connection == NULL)
186 if (transport->disconnected)
188 _dbus_assert (socket_transport->read_watch == NULL);
192 _dbus_transport_ref (transport);
194 if (_dbus_transport_try_to_authenticate (transport))
196 (_dbus_counter_get_size_value (transport->live_messages) < transport->max_live_messages_size) &&
197 (_dbus_counter_get_unix_fd_value (transport->live_messages) < transport->max_live_messages_unix_fds);
200 if (transport->receive_credentials_pending)
201 need_read_watch = TRUE;
204 /* The reason to disable need_read_watch when not WAITING_FOR_INPUT
205 * is to avoid spinning on the file descriptor when we're waiting
206 * to write or for some other part of the auth process
208 DBusAuthState auth_state;
210 auth_state = _dbus_auth_do_work (transport->auth);
212 /* If we need memory we install the read watch just in case,
213 * if there's no need for it, it will get de-installed
214 * next time we try reading. If we're authenticated we
215 * install it since we normally have it installed while
218 if (auth_state == DBUS_AUTH_STATE_WAITING_FOR_INPUT ||
219 auth_state == DBUS_AUTH_STATE_WAITING_FOR_MEMORY ||
220 auth_state == DBUS_AUTH_STATE_AUTHENTICATED)
221 need_read_watch = TRUE;
223 need_read_watch = FALSE;
227 _dbus_verbose (" setting read watch enabled = %d\n", need_read_watch);
228 _dbus_connection_toggle_watch_unlocked (transport->connection,
229 socket_transport->read_watch,
232 _dbus_transport_unref (transport);
236 do_io_error (DBusTransport *transport)
238 _dbus_transport_ref (transport);
239 _dbus_transport_disconnect (transport);
240 _dbus_transport_unref (transport);
243 /* return value is whether we successfully read any new data. */
245 read_data_into_auth (DBusTransport *transport,
248 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
255 _dbus_auth_get_buffer (transport->auth, &buffer);
257 bytes_read = _dbus_read_socket (socket_transport->fd,
258 buffer, socket_transport->max_bytes_read_per_iteration);
259 saved_errno = _dbus_save_socket_errno ();
261 _dbus_auth_return_buffer (transport->auth, buffer);
265 _dbus_verbose (" read %d bytes in auth phase\n", bytes_read);
269 else if (bytes_read < 0)
271 /* EINTR already handled for us */
273 if (_dbus_get_is_errno_enomem (saved_errno))
277 else if (_dbus_get_is_errno_eagain_or_ewouldblock (saved_errno))
278 ; /* do nothing, just return FALSE below */
281 _dbus_verbose ("Error reading from remote app: %s\n",
282 _dbus_strerror (saved_errno));
283 do_io_error (transport);
290 _dbus_assert (bytes_read == 0);
292 _dbus_verbose ("Disconnected from remote app\n");
293 do_io_error (transport);
299 /* Return value is whether we successfully wrote any bytes */
301 write_data_from_auth (DBusTransport *transport)
303 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
306 const DBusString *buffer;
308 if (!_dbus_auth_get_bytes_to_send (transport->auth,
312 bytes_written = _dbus_write_socket (socket_transport->fd,
314 0, _dbus_string_get_length (buffer));
315 saved_errno = _dbus_save_socket_errno ();
317 if (bytes_written > 0)
319 _dbus_auth_bytes_sent (transport->auth, bytes_written);
322 else if (bytes_written < 0)
324 /* EINTR already handled for us */
326 if (_dbus_get_is_errno_eagain_or_ewouldblock (saved_errno))
330 _dbus_verbose ("Error writing to remote app: %s\n",
331 _dbus_strerror (saved_errno));
332 do_io_error (transport);
341 exchange_credentials (DBusTransport *transport,
342 dbus_bool_t do_reading,
343 dbus_bool_t do_writing)
345 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
346 DBusError error = DBUS_ERROR_INIT;
348 _dbus_verbose ("exchange_credentials: do_reading = %d, do_writing = %d\n",
349 do_reading, do_writing);
351 if (do_writing && transport->send_credentials_pending)
353 if (_dbus_send_credentials_socket (socket_transport->fd,
356 transport->send_credentials_pending = FALSE;
360 _dbus_verbose ("Failed to write credentials: %s\n", error.message);
361 dbus_error_free (&error);
362 do_io_error (transport);
366 if (do_reading && transport->receive_credentials_pending)
368 /* FIXME this can fail due to IO error _or_ OOM, broken
369 * (somewhat tricky to fix since the OOM error can be set after
370 * we already read the credentials byte, so basically we need to
371 * separate reading the byte and storing it in the
372 * transport->credentials). Does not really matter for now
373 * because storing in credentials never actually fails on unix.
375 if (_dbus_read_credentials_socket (socket_transport->fd,
376 transport->credentials,
379 transport->receive_credentials_pending = FALSE;
383 _dbus_verbose ("Failed to read credentials %s\n", error.message);
384 dbus_error_free (&error);
385 do_io_error (transport);
389 if (!(transport->send_credentials_pending ||
390 transport->receive_credentials_pending))
392 if (!_dbus_auth_set_credentials (transport->auth,
393 transport->credentials))
401 do_authentication (DBusTransport *transport,
402 dbus_bool_t do_reading,
403 dbus_bool_t do_writing,
404 dbus_bool_t *auth_completed)
407 dbus_bool_t orig_auth_state;
411 orig_auth_state = _dbus_transport_try_to_authenticate (transport);
413 /* This is essential to avoid the check_write_watch() at the end,
414 * we don't want to add a write watch in do_iteration before
415 * we try writing and get EAGAIN
420 *auth_completed = FALSE;
424 _dbus_transport_ref (transport);
426 while (!_dbus_transport_try_to_authenticate (transport) &&
427 _dbus_transport_get_is_connected (transport))
429 if (!exchange_credentials (transport, do_reading, do_writing))
436 if (transport->send_credentials_pending ||
437 transport->receive_credentials_pending)
439 _dbus_verbose ("send_credentials_pending = %d receive_credentials_pending = %d\n",
440 transport->send_credentials_pending,
441 transport->receive_credentials_pending);
445 #define TRANSPORT_SIDE(t) ((t)->is_server ? "server" : "client")
446 switch (_dbus_auth_do_work (transport->auth))
448 case DBUS_AUTH_STATE_WAITING_FOR_INPUT:
449 _dbus_verbose (" %s auth state: waiting for input\n",
450 TRANSPORT_SIDE (transport));
451 if (!do_reading || !read_data_into_auth (transport, &oom))
455 case DBUS_AUTH_STATE_WAITING_FOR_MEMORY:
456 _dbus_verbose (" %s auth state: waiting for memory\n",
457 TRANSPORT_SIDE (transport));
462 case DBUS_AUTH_STATE_HAVE_BYTES_TO_SEND:
463 _dbus_verbose (" %s auth state: bytes to send\n",
464 TRANSPORT_SIDE (transport));
465 if (!do_writing || !write_data_from_auth (transport))
469 case DBUS_AUTH_STATE_NEED_DISCONNECT:
470 _dbus_verbose (" %s auth state: need to disconnect\n",
471 TRANSPORT_SIDE (transport));
472 do_io_error (transport);
475 case DBUS_AUTH_STATE_AUTHENTICATED:
476 _dbus_verbose (" %s auth state: authenticated\n",
477 TRANSPORT_SIDE (transport));
480 _dbus_assert_not_reached ("invalid auth state");
486 *auth_completed = (orig_auth_state != _dbus_transport_try_to_authenticate (transport));
488 check_read_watch (transport);
489 check_write_watch (transport);
490 _dbus_transport_unref (transport);
498 /* returns false on oom */
500 do_writing (DBusTransport *transport)
503 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
506 /* No messages without authentication! */
507 if (!_dbus_transport_try_to_authenticate (transport))
509 _dbus_verbose ("Not authenticated, not writing anything\n");
513 if (transport->disconnected)
515 _dbus_verbose ("Not connected, not writing anything\n");
520 _dbus_verbose ("do_writing(), have_messages = %d, fd = %" DBUS_SOCKET_FORMAT "\n",
521 _dbus_connection_has_messages_to_send_unlocked (transport->connection),
522 _dbus_socket_printable (socket_transport->fd));
528 while (!transport->disconnected &&
529 _dbus_connection_has_messages_to_send_unlocked (transport->connection))
532 DBusMessage *message;
533 const DBusString *header;
534 const DBusString *body;
535 int header_len, body_len;
536 int total_bytes_to_write;
539 if (total > socket_transport->max_bytes_written_per_iteration)
541 _dbus_verbose ("%d bytes exceeds %d bytes written per iteration, returning\n",
542 total, socket_transport->max_bytes_written_per_iteration);
546 message = _dbus_connection_get_message_to_send (transport->connection);
547 _dbus_assert (message != NULL);
548 dbus_message_lock (message);
551 _dbus_verbose ("writing message %p\n", message);
554 _dbus_message_get_network_data (message,
557 header_len = _dbus_string_get_length (header);
558 body_len = _dbus_string_get_length (body);
560 if (_dbus_auth_needs_encoding (transport->auth))
562 /* Does fd passing even make sense with encoded data? */
563 _dbus_assert(!DBUS_TRANSPORT_CAN_SEND_UNIX_FD(transport));
565 if (_dbus_string_get_length (&socket_transport->encoded_outgoing) == 0)
567 if (!_dbus_auth_encode_data (transport->auth,
568 header, &socket_transport->encoded_outgoing))
574 if (!_dbus_auth_encode_data (transport->auth,
575 body, &socket_transport->encoded_outgoing))
577 _dbus_string_set_length (&socket_transport->encoded_outgoing, 0);
583 total_bytes_to_write = _dbus_string_get_length (&socket_transport->encoded_outgoing);
586 _dbus_verbose ("encoded message is %d bytes\n",
587 total_bytes_to_write);
591 _dbus_write_socket (socket_transport->fd,
592 &socket_transport->encoded_outgoing,
593 socket_transport->message_bytes_written,
594 total_bytes_to_write - socket_transport->message_bytes_written);
595 saved_errno = _dbus_save_socket_errno ();
599 total_bytes_to_write = header_len + body_len;
602 _dbus_verbose ("message is %d bytes\n",
603 total_bytes_to_write);
606 #ifdef HAVE_UNIX_FD_PASSING
607 if (socket_transport->message_bytes_written <= 0 && DBUS_TRANSPORT_CAN_SEND_UNIX_FD(transport))
609 /* Send the fds along with the first byte of the message */
613 _dbus_message_get_unix_fds(message, &unix_fds, &n);
616 _dbus_write_socket_with_unix_fds_two (socket_transport->fd,
618 socket_transport->message_bytes_written,
619 header_len - socket_transport->message_bytes_written,
624 saved_errno = _dbus_save_socket_errno ();
626 if (bytes_written > 0 && n > 0)
627 _dbus_verbose("Wrote %i unix fds\n", n);
632 if (socket_transport->message_bytes_written < header_len)
635 _dbus_write_socket_two (socket_transport->fd,
637 socket_transport->message_bytes_written,
638 header_len - socket_transport->message_bytes_written,
645 _dbus_write_socket (socket_transport->fd,
647 (socket_transport->message_bytes_written - header_len),
649 (socket_transport->message_bytes_written - header_len));
652 saved_errno = _dbus_save_socket_errno ();
656 if (bytes_written < 0)
658 /* EINTR already handled for us */
660 /* If the other end closed the socket with close() or shutdown(), we
661 * receive EPIPE here but we must not close the socket yet: there
662 * might still be some data to read. See:
663 * http://lists.freedesktop.org/archives/dbus/2008-March/009526.html
666 if (_dbus_get_is_errno_eagain_or_ewouldblock (saved_errno) || _dbus_get_is_errno_epipe (saved_errno))
669 /* Since Linux commit 25888e (from 2.6.37-rc4, Nov 2010), sendmsg()
670 * on Unix sockets returns -1 errno=ETOOMANYREFS when the passfd
671 * mechanism (SCM_RIGHTS) is used recursively with a recursion level
672 * of maximum 4. The kernel does not have an API to check whether
673 * the passed fds can be forwarded and it can change asynchronously.
675 * https://bugs.freedesktop.org/show_bug.cgi?id=80163
678 else if (_dbus_get_is_errno_etoomanyrefs (saved_errno))
680 /* We only send fds in the first byte of the message.
681 * ETOOMANYREFS cannot happen after.
683 _dbus_assert (socket_transport->message_bytes_written == 0);
685 _dbus_verbose (" discard message of %d bytes due to ETOOMANYREFS\n",
686 total_bytes_to_write);
688 socket_transport->message_bytes_written = 0;
689 _dbus_string_set_length (&socket_transport->encoded_outgoing, 0);
690 _dbus_string_compact (&socket_transport->encoded_outgoing, 2048);
692 /* The message was not actually sent but it needs to be removed
693 * from the outgoing queue
695 _dbus_connection_message_sent_unlocked (transport->connection,
700 _dbus_verbose ("Error writing to remote app: %s\n",
701 _dbus_strerror (saved_errno));
702 do_io_error (transport);
708 _dbus_verbose (" wrote %d bytes of %d\n", bytes_written,
709 total_bytes_to_write);
711 total += bytes_written;
712 socket_transport->message_bytes_written += bytes_written;
714 _dbus_assert (socket_transport->message_bytes_written <=
715 total_bytes_to_write);
717 if (socket_transport->message_bytes_written == total_bytes_to_write)
719 socket_transport->message_bytes_written = 0;
720 _dbus_string_set_length (&socket_transport->encoded_outgoing, 0);
721 _dbus_string_compact (&socket_transport->encoded_outgoing, 2048);
723 _dbus_connection_message_sent_unlocked (transport->connection,
736 /* returns false on out-of-memory */
738 do_reading (DBusTransport *transport)
740 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
747 _dbus_verbose ("fd = %" DBUS_SOCKET_FORMAT "\n",
748 _dbus_socket_printable (socket_transport->fd));
750 /* No messages without authentication! */
751 if (!_dbus_transport_try_to_authenticate (transport))
760 /* See if we've exceeded max messages and need to disable reading */
761 check_read_watch (transport);
763 if (total > socket_transport->max_bytes_read_per_iteration)
765 _dbus_verbose ("%d bytes exceeds %d bytes read per iteration, returning\n",
766 total, socket_transport->max_bytes_read_per_iteration);
770 _dbus_assert (socket_transport->read_watch != NULL ||
771 transport->disconnected);
773 if (transport->disconnected)
776 if (!dbus_watch_get_enabled (socket_transport->read_watch))
779 if (_dbus_auth_needs_decoding (transport->auth))
781 /* Does fd passing even make sense with encoded data? */
782 _dbus_assert(!DBUS_TRANSPORT_CAN_SEND_UNIX_FD(transport));
784 if (_dbus_string_get_length (&socket_transport->encoded_incoming) > 0)
785 bytes_read = _dbus_string_get_length (&socket_transport->encoded_incoming);
787 bytes_read = _dbus_read_socket (socket_transport->fd,
788 &socket_transport->encoded_incoming,
789 socket_transport->max_bytes_read_per_iteration);
791 saved_errno = _dbus_save_socket_errno ();
793 _dbus_assert (_dbus_string_get_length (&socket_transport->encoded_incoming) ==
798 _dbus_message_loader_get_buffer (transport->loader,
803 if (!_dbus_auth_decode_data (transport->auth,
804 &socket_transport->encoded_incoming,
807 _dbus_verbose ("Out of memory decoding incoming data\n");
808 _dbus_message_loader_return_buffer (transport->loader,
815 _dbus_message_loader_return_buffer (transport->loader,
818 _dbus_string_set_length (&socket_transport->encoded_incoming, 0);
819 _dbus_string_compact (&socket_transport->encoded_incoming, 2048);
824 int max_to_read = DBUS_MAXIMUM_MESSAGE_LENGTH;
825 dbus_bool_t may_read_unix_fds = TRUE;
827 _dbus_message_loader_get_buffer (transport->loader,
832 if (max_to_read > socket_transport->max_bytes_read_per_iteration)
833 max_to_read = socket_transport->max_bytes_read_per_iteration;
835 #ifdef HAVE_UNIX_FD_PASSING
836 if (DBUS_TRANSPORT_CAN_SEND_UNIX_FD(transport) && may_read_unix_fds)
841 if (!_dbus_message_loader_get_unix_fds(transport->loader, &fds, &n_fds))
843 _dbus_verbose ("Out of memory reading file descriptors\n");
844 _dbus_message_loader_return_buffer (transport->loader, buffer);
849 bytes_read = _dbus_read_socket_with_unix_fds(socket_transport->fd,
853 saved_errno = _dbus_save_socket_errno ();
855 if (bytes_read >= 0 && n_fds > 0)
856 _dbus_verbose("Read %i unix fds\n", n_fds);
858 _dbus_message_loader_return_unix_fds(transport->loader, fds, bytes_read < 0 ? 0 : n_fds);
863 bytes_read = _dbus_read_socket (socket_transport->fd,
864 buffer, max_to_read);
865 saved_errno = _dbus_save_socket_errno ();
868 _dbus_message_loader_return_buffer (transport->loader,
874 /* EINTR already handled for us */
876 if (_dbus_get_is_errno_enomem (saved_errno))
878 _dbus_verbose ("Out of memory in read()/do_reading()\n");
882 else if (_dbus_get_is_errno_eagain_or_ewouldblock (saved_errno))
886 _dbus_verbose ("Error reading from remote app: %s\n",
887 _dbus_strerror (saved_errno));
888 do_io_error (transport);
892 else if (bytes_read == 0)
894 _dbus_verbose ("Disconnected from remote app\n");
895 do_io_error (transport);
900 _dbus_verbose (" read %d bytes\n", bytes_read);
904 if (!_dbus_transport_queue_messages (transport))
907 _dbus_verbose (" out of memory when queueing messages we just read in the transport\n");
911 /* Try reading more data until we get EAGAIN and return, or
912 * exceed max bytes per iteration. If in blocking mode of
913 * course we'll block instead of returning.
926 unix_error_with_read_to_come (DBusTransport *itransport,
930 DBusTransportSocket *transport = (DBusTransportSocket *) itransport;
932 if (!(flags & DBUS_WATCH_HANGUP || flags & DBUS_WATCH_ERROR))
935 /* If we have a read watch enabled ...
936 we -might have data incoming ... => handle the HANGUP there */
937 if (watch != transport->read_watch &&
938 _dbus_watch_get_enabled (transport->read_watch))
945 socket_handle_watch (DBusTransport *transport,
949 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
951 _dbus_assert (watch == socket_transport->read_watch ||
952 watch == socket_transport->write_watch);
953 _dbus_assert (watch != NULL);
955 /* If we hit an error here on a write watch, don't disconnect the transport yet because data can
956 * still be in the buffer and do_reading may need several iteration to read
957 * it all (because of its max_bytes_read_per_iteration limit).
959 if (!(flags & DBUS_WATCH_READABLE) && unix_error_with_read_to_come (transport, watch, flags))
961 _dbus_verbose ("Hang up or error on watch\n");
962 _dbus_transport_disconnect (transport);
966 if (watch == socket_transport->read_watch &&
967 (flags & DBUS_WATCH_READABLE))
969 dbus_bool_t auth_finished;
971 _dbus_verbose ("handling read watch %p flags = %x\n",
974 if (!do_authentication (transport, TRUE, FALSE, &auth_finished))
977 /* We don't want to do a read immediately following
978 * a successful authentication. This is so we
979 * have a chance to propagate the authentication
980 * state further up. Specifically, we need to
981 * process any pending data from the auth object.
985 if (!do_reading (transport))
987 _dbus_verbose ("no memory to read\n");
993 _dbus_verbose ("Not reading anything since we just completed the authentication\n");
996 else if (watch == socket_transport->write_watch &&
997 (flags & DBUS_WATCH_WRITABLE))
1000 _dbus_verbose ("handling write watch, have_outgoing_messages = %d\n",
1001 _dbus_connection_has_messages_to_send_unlocked (transport->connection));
1003 if (!do_authentication (transport, FALSE, TRUE, NULL))
1006 if (!do_writing (transport))
1008 _dbus_verbose ("no memory to write\n");
1012 /* See if we still need the write watch */
1013 check_write_watch (transport);
1015 #ifdef DBUS_ENABLE_VERBOSE_MODE
1018 if (watch == socket_transport->read_watch)
1019 _dbus_verbose ("asked to handle read watch with non-read condition 0x%x\n",
1021 else if (watch == socket_transport->write_watch)
1022 _dbus_verbose ("asked to handle write watch with non-write condition 0x%x\n",
1025 _dbus_verbose ("asked to handle watch %p on fd %" DBUS_SOCKET_FORMAT " that we don't recognize\n",
1026 watch, dbus_watch_get_socket (watch));
1028 #endif /* DBUS_ENABLE_VERBOSE_MODE */
1034 socket_disconnect (DBusTransport *transport)
1036 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
1038 _dbus_verbose ("\n");
1040 free_watches (transport);
1042 _dbus_close_socket (socket_transport->fd, NULL);
1043 _dbus_socket_invalidate (&socket_transport->fd);
1047 socket_connection_set (DBusTransport *transport)
1049 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
1051 _dbus_watch_set_handler (socket_transport->write_watch,
1052 _dbus_connection_handle_watch,
1053 transport->connection, NULL);
1055 _dbus_watch_set_handler (socket_transport->read_watch,
1056 _dbus_connection_handle_watch,
1057 transport->connection, NULL);
1059 if (!_dbus_connection_add_watch_unlocked (transport->connection,
1060 socket_transport->write_watch))
1063 if (!_dbus_connection_add_watch_unlocked (transport->connection,
1064 socket_transport->read_watch))
1066 _dbus_connection_remove_watch_unlocked (transport->connection,
1067 socket_transport->write_watch);
1071 check_read_watch (transport);
1072 check_write_watch (transport);
1078 * @todo We need to have a way to wake up the select sleep if
1079 * a new iteration request comes in with a flag (read/write) that
1080 * we're not currently serving. Otherwise a call that just reads
1081 * could block a write call forever (if there are no incoming
1085 socket_do_iteration (DBusTransport *transport,
1087 int timeout_milliseconds)
1089 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
1094 _dbus_verbose (" iteration flags = %s%s timeout = %d read_watch = %p write_watch = %p fd = %" DBUS_SOCKET_FORMAT "\n",
1095 flags & DBUS_ITERATION_DO_READING ? "read" : "",
1096 flags & DBUS_ITERATION_DO_WRITING ? "write" : "",
1097 timeout_milliseconds,
1098 socket_transport->read_watch,
1099 socket_transport->write_watch,
1100 _dbus_socket_printable (socket_transport->fd));
1102 /* the passed in DO_READING/DO_WRITING flags indicate whether to
1103 * read/write messages, but regardless of those we may need to block
1104 * for reading/writing to do auth. But if we do reading for auth,
1105 * we don't want to read any messages yet if not given DO_READING.
1108 poll_fd.fd = _dbus_socket_get_pollable (socket_transport->fd);
1111 if (_dbus_transport_try_to_authenticate (transport))
1113 /* This is kind of a hack; if we have stuff to write, then try
1114 * to avoid the poll. This is probably about a 5% speedup on an
1115 * echo client/server.
1117 * If both reading and writing were requested, we want to avoid this
1118 * since it could have funky effects:
1119 * - both ends spinning waiting for the other one to read
1120 * data so they can finish writing
1121 * - prioritizing all writing ahead of reading
1123 if ((flags & DBUS_ITERATION_DO_WRITING) &&
1124 !(flags & (DBUS_ITERATION_DO_READING | DBUS_ITERATION_BLOCK)) &&
1125 !transport->disconnected &&
1126 _dbus_connection_has_messages_to_send_unlocked (transport->connection))
1128 do_writing (transport);
1130 if (transport->disconnected ||
1131 !_dbus_connection_has_messages_to_send_unlocked (transport->connection))
1135 /* If we get here, we decided to do the poll() after all */
1136 _dbus_assert (socket_transport->read_watch);
1137 if (flags & DBUS_ITERATION_DO_READING)
1138 poll_fd.events |= _DBUS_POLLIN;
1140 _dbus_assert (socket_transport->write_watch);
1141 if (flags & DBUS_ITERATION_DO_WRITING)
1142 poll_fd.events |= _DBUS_POLLOUT;
1146 DBusAuthState auth_state;
1148 auth_state = _dbus_auth_do_work (transport->auth);
1150 if (transport->receive_credentials_pending ||
1151 auth_state == DBUS_AUTH_STATE_WAITING_FOR_INPUT)
1152 poll_fd.events |= _DBUS_POLLIN;
1154 if (transport->send_credentials_pending ||
1155 auth_state == DBUS_AUTH_STATE_HAVE_BYTES_TO_SEND)
1156 poll_fd.events |= _DBUS_POLLOUT;
1163 if (flags & DBUS_ITERATION_BLOCK)
1164 poll_timeout = timeout_milliseconds;
1168 /* For blocking selects we drop the connection lock here
1169 * to avoid blocking out connection access during a potentially
1170 * indefinite blocking call. The io path is still protected
1171 * by the io_path_cond condvar, so we won't reenter this.
1173 if (flags & DBUS_ITERATION_BLOCK)
1175 _dbus_verbose ("unlock pre poll\n");
1176 _dbus_connection_unlock (transport->connection);
1180 poll_res = _dbus_poll (&poll_fd, 1, poll_timeout);
1181 saved_errno = _dbus_save_socket_errno ();
1183 if (poll_res < 0 && _dbus_get_is_errno_eintr (saved_errno))
1186 if (flags & DBUS_ITERATION_BLOCK)
1188 _dbus_verbose ("lock post poll\n");
1189 _dbus_connection_lock (transport->connection);
1195 poll_fd.revents = 0; /* some concern that posix does not guarantee this;
1196 * valgrind flags it as an error. though it probably
1197 * is guaranteed on linux at least.
1200 if (poll_fd.revents & _DBUS_POLLERR)
1201 do_io_error (transport);
1204 dbus_bool_t need_read = (poll_fd.revents & _DBUS_POLLIN) > 0;
1205 dbus_bool_t need_write = (poll_fd.revents & _DBUS_POLLOUT) > 0;
1206 dbus_bool_t authentication_completed;
1208 _dbus_verbose ("in iteration, need_read=%d need_write=%d\n",
1209 need_read, need_write);
1210 do_authentication (transport, need_read, need_write,
1211 &authentication_completed);
1213 /* See comment in socket_handle_watch. */
1214 if (authentication_completed)
1217 if (need_read && (flags & DBUS_ITERATION_DO_READING))
1218 do_reading (transport);
1219 if (need_write && (flags & DBUS_ITERATION_DO_WRITING))
1220 do_writing (transport);
1225 _dbus_verbose ("Error from _dbus_poll(): %s\n",
1226 _dbus_strerror (saved_errno));
1232 /* We need to install the write watch only if we did not
1233 * successfully write everything. Note we need to be careful that we
1234 * don't call check_write_watch *before* do_writing, since it's
1235 * inefficient to add the write watch, and we can avoid it most of
1236 * the time since we can write immediately.
1238 * However, we MUST always call check_write_watch(); DBusConnection code
1239 * relies on the fact that running an iteration will notice that
1240 * messages are pending.
1242 check_write_watch (transport);
1244 _dbus_verbose (" ... leaving do_iteration()\n");
1248 socket_live_messages_changed (DBusTransport *transport)
1250 /* See if we should look for incoming messages again */
1251 check_read_watch (transport);
1256 socket_get_socket_fd (DBusTransport *transport,
1259 DBusTransportSocket *socket_transport = (DBusTransportSocket*) transport;
1261 *fd_p = socket_transport->fd;
1266 static const DBusTransportVTable socket_vtable = {
1268 socket_handle_watch,
1270 socket_connection_set,
1271 socket_do_iteration,
1272 socket_live_messages_changed,
1273 socket_get_socket_fd
1277 * Creates a new transport for the given socket file descriptor. The file
1278 * descriptor must be nonblocking (use _dbus_set_fd_nonblocking() to
1279 * make it so). This function is shared by various transports that
1280 * boil down to a full duplex file descriptor.
1282 * @param fd the file descriptor.
1283 * @param server_guid non-#NULL if this transport is on the server side of a connection
1284 * @param address the transport's address
1285 * @returns the new transport, or #NULL if no memory.
1288 _dbus_transport_new_for_socket (DBusSocket fd,
1289 const DBusString *server_guid,
1290 const DBusString *address)
1292 DBusTransportSocket *socket_transport;
1294 socket_transport = dbus_new0 (DBusTransportSocket, 1);
1295 if (socket_transport == NULL)
1298 if (!_dbus_string_init (&socket_transport->encoded_outgoing))
1301 if (!_dbus_string_init (&socket_transport->encoded_incoming))
1304 socket_transport->write_watch = _dbus_watch_new (_dbus_socket_get_pollable (fd),
1305 DBUS_WATCH_WRITABLE,
1308 if (socket_transport->write_watch == NULL)
1311 socket_transport->read_watch = _dbus_watch_new (_dbus_socket_get_pollable (fd),
1312 DBUS_WATCH_READABLE,
1315 if (socket_transport->read_watch == NULL)
1318 if (!_dbus_transport_init_base (&socket_transport->base,
1320 server_guid, address))
1323 #ifdef HAVE_UNIX_FD_PASSING
1324 _dbus_auth_set_unix_fd_possible(socket_transport->base.auth, _dbus_socket_can_pass_unix_fd(fd));
1327 socket_transport->fd = fd;
1328 socket_transport->message_bytes_written = 0;
1330 /* These values should probably be tunable or something. */
1331 socket_transport->max_bytes_read_per_iteration = 2048;
1332 socket_transport->max_bytes_written_per_iteration = 2048;
1334 return (DBusTransport*) socket_transport;
1337 _dbus_watch_invalidate (socket_transport->read_watch);
1338 _dbus_watch_unref (socket_transport->read_watch);
1340 _dbus_watch_invalidate (socket_transport->write_watch);
1341 _dbus_watch_unref (socket_transport->write_watch);
1343 _dbus_string_free (&socket_transport->encoded_incoming);
1345 _dbus_string_free (&socket_transport->encoded_outgoing);
1347 dbus_free (socket_transport);
1352 * Creates a new transport for the given hostname and port.
1353 * If host is NULL, it will default to localhost
1355 * @param host the host to connect to
1356 * @param port the port to connect to
1357 * @param family the address family to connect to
1358 * @param noncefile path to nonce file
1359 * @param error location to store reason for failure.
1360 * @returns a new transport, or #NULL on failure.
1363 _dbus_transport_new_for_tcp_socket (const char *host,
1366 const char *noncefile,
1370 DBusTransport *transport;
1373 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
1375 if (!_dbus_string_init (&address))
1377 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
1384 if (!_dbus_string_append (&address, noncefile ? "nonce-tcp:" : "tcp:"))
1387 if (!_dbus_string_append (&address, "host=") ||
1388 !_dbus_string_append (&address, host))
1391 if (!_dbus_string_append (&address, ",port=") ||
1392 !_dbus_string_append (&address, port))
1395 if (family != NULL &&
1396 (!_dbus_string_append (&address, ",family=") ||
1397 !_dbus_string_append (&address, family)))
1400 if (noncefile != NULL &&
1401 (!_dbus_string_append (&address, ",noncefile=") ||
1402 !_dbus_string_append (&address, noncefile)))
1405 fd = _dbus_connect_tcp_socket_with_nonce (host, port, family, noncefile, error);
1406 if (!_dbus_socket_is_valid (fd))
1408 _DBUS_ASSERT_ERROR_IS_SET (error);
1409 _dbus_string_free (&address);
1413 _dbus_verbose ("Successfully connected to tcp socket %s:%s\n",
1416 transport = _dbus_transport_new_for_socket (fd, NULL, &address);
1417 _dbus_string_free (&address);
1418 if (transport == NULL)
1420 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
1421 _dbus_close_socket (fd, NULL);
1422 _dbus_socket_invalidate (&fd);
1428 _dbus_string_free (&address);
1429 dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
1434 * Opens a TCP socket transport.
1436 * @param entry the address entry to try opening as a tcp transport.
1437 * @param transport_p return location for the opened transport
1438 * @param error error to be set
1439 * @returns result of the attempt
1441 DBusTransportOpenResult
1442 _dbus_transport_open_socket(DBusAddressEntry *entry,
1443 DBusTransport **transport_p,
1448 dbus_bool_t isNonceTcp;
1450 method = dbus_address_entry_get_method (entry);
1451 _dbus_assert (method != NULL);
1453 isTcp = strcmp (method, "tcp") == 0;
1454 isNonceTcp = strcmp (method, "nonce-tcp") == 0;
1456 if (isTcp || isNonceTcp)
1458 const char *host = dbus_address_entry_get_value (entry, "host");
1459 const char *port = dbus_address_entry_get_value (entry, "port");
1460 const char *family = dbus_address_entry_get_value (entry, "family");
1461 const char *noncefile = dbus_address_entry_get_value (entry, "noncefile");
1463 if ((isNonceTcp == TRUE) != (noncefile != NULL)) {
1464 _dbus_set_bad_address (error, method, "noncefile", NULL);
1465 return DBUS_TRANSPORT_OPEN_BAD_ADDRESS;
1470 _dbus_set_bad_address (error, method, "port", NULL);
1471 return DBUS_TRANSPORT_OPEN_BAD_ADDRESS;
1474 *transport_p = _dbus_transport_new_for_tcp_socket (host, port, family, noncefile, error);
1475 if (*transport_p == NULL)
1477 _DBUS_ASSERT_ERROR_IS_SET (error);
1478 return DBUS_TRANSPORT_OPEN_DID_NOT_CONNECT;
1482 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
1483 return DBUS_TRANSPORT_OPEN_OK;
1488 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
1489 return DBUS_TRANSPORT_OPEN_NOT_HANDLED;