D-Bus  1.13.7
dbus-server-socket.c
1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
2 /* dbus-server-socket.c Server implementation for sockets
3  *
4  * Copyright (C) 2002, 2003, 2004, 2006 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 <config.h>
25 #include "dbus-internals.h"
26 #include "dbus-server-socket.h"
27 #include "dbus-transport-socket.h"
28 #include "dbus-connection-internal.h"
29 #include "dbus-memory.h"
30 #include "dbus-nonce.h"
31 #include "dbus-string.h"
32 
45 
51 {
53  int n_fds;
56  char *socket_name;
58 };
59 
60 static void
61 socket_finalize (DBusServer *server)
62 {
63  DBusServerSocket *socket_server = (DBusServerSocket*) server;
64  int i;
65 
67 
68  for (i = 0 ; i < socket_server->n_fds ; i++)
69  if (socket_server->watch[i])
70  {
71  _dbus_watch_unref (socket_server->watch[i]);
72  socket_server->watch[i] = NULL;
73  }
74 
75  dbus_free (socket_server->fds);
76  dbus_free (socket_server->watch);
77  dbus_free (socket_server->socket_name);
78  _dbus_noncefile_delete (&socket_server->noncefile, NULL);
79  dbus_free (server);
80 }
81 
82 /* Return value is just for memory, not other failures. */
83 static dbus_bool_t
84 handle_new_client_fd_and_unlock (DBusServer *server,
85  DBusSocket client_fd)
86 {
87  DBusConnection *connection;
88  DBusTransport *transport;
89  DBusNewConnectionFunction new_connection_function;
90  void *new_connection_data;
91 
92  _dbus_verbose ("Creating new client connection with fd %" DBUS_SOCKET_FORMAT "\n",
93  _dbus_socket_printable (client_fd));
94 
95  HAVE_LOCK_CHECK (server);
96 
97  if (!_dbus_set_socket_nonblocking (client_fd, NULL))
98  {
99  SERVER_UNLOCK (server);
100  return TRUE;
101  }
102 
103  transport = _dbus_transport_new_for_socket (client_fd, &server->guid_hex, NULL);
104  if (transport == NULL)
105  {
106  _dbus_close_socket (client_fd, NULL);
107  SERVER_UNLOCK (server);
108  return FALSE;
109  }
110 
111  if (!_dbus_transport_set_auth_mechanisms (transport,
112  (const char **) server->auth_mechanisms))
113  {
114  _dbus_transport_unref (transport);
115  SERVER_UNLOCK (server);
116  return FALSE;
117  }
118 
119  /* note that client_fd is now owned by the transport, and will be
120  * closed on transport disconnection/finalization
121  */
122 
123  connection = _dbus_connection_new_for_transport (transport);
124  _dbus_transport_unref (transport);
125  transport = NULL; /* now under the connection lock */
126 
127  if (connection == NULL)
128  {
129  SERVER_UNLOCK (server);
130  return FALSE;
131  }
132 
133  /* See if someone wants to handle this new connection, self-referencing
134  * for paranoia.
135  */
136  new_connection_function = server->new_connection_function;
137  new_connection_data = server->new_connection_data;
138 
139  _dbus_server_ref_unlocked (server);
140  SERVER_UNLOCK (server);
141 
142  if (new_connection_function)
143  {
144  (* new_connection_function) (server, connection,
145  new_connection_data);
146  }
147  dbus_server_unref (server);
148 
149  /* If no one grabbed a reference, the connection will die. */
151  dbus_connection_unref (connection);
152 
153  return TRUE;
154 }
155 
156 static dbus_bool_t
157 socket_handle_watch (DBusWatch *watch,
158  unsigned int flags,
159  void *data)
160 {
161  DBusServer *server = data;
162  DBusServerSocket *socket_server = data;
163 
164 #ifndef DBUS_DISABLE_ASSERT
165  int i;
166  dbus_bool_t found = FALSE;
167 #endif
168 
169  SERVER_LOCK (server);
170 
171 #ifndef DBUS_DISABLE_ASSERT
172  for (i = 0 ; i < socket_server->n_fds ; i++)
173  {
174  if (socket_server->watch[i] == watch)
175  found = TRUE;
176  }
177  _dbus_assert (found);
178 #endif
179 
180  _dbus_verbose ("Handling client connection, flags 0x%x\n", flags);
181 
182  if (flags & DBUS_WATCH_READABLE)
183  {
184  DBusSocket client_fd;
185  DBusSocket listen_fd;
186  int saved_errno;
187 
188  listen_fd = _dbus_watch_get_socket (watch);
189 
190  if (socket_server->noncefile)
191  client_fd = _dbus_accept_with_noncefile (listen_fd, socket_server->noncefile);
192  else
193  client_fd = _dbus_accept (listen_fd);
194 
195  saved_errno = _dbus_save_socket_errno ();
196 
197  if (!_dbus_socket_is_valid (client_fd))
198  {
199  /* EINTR handled for us */
200 
202  _dbus_verbose ("No client available to accept after all\n");
203  else
204  _dbus_verbose ("Failed to accept a client connection: %s\n",
205  _dbus_strerror (saved_errno));
206 
207  SERVER_UNLOCK (server);
208  }
209  else
210  {
211  if (!handle_new_client_fd_and_unlock (server, client_fd))
212  _dbus_verbose ("Rejected client connection due to lack of memory\n");
213  }
214  }
215 
216  if (flags & DBUS_WATCH_ERROR)
217  _dbus_verbose ("Error on server listening socket\n");
218 
219  if (flags & DBUS_WATCH_HANGUP)
220  _dbus_verbose ("Hangup on server listening socket\n");
221 
222  return TRUE;
223 }
224 
225 static void
226 socket_disconnect (DBusServer *server)
227 {
228  DBusServerSocket *socket_server = (DBusServerSocket*) server;
229  int i;
230 
231  HAVE_LOCK_CHECK (server);
232 
233  for (i = 0 ; i < socket_server->n_fds ; i++)
234  {
235  if (socket_server->watch[i])
236  {
238  socket_server->watch[i]);
239  _dbus_watch_invalidate (socket_server->watch[i]);
240  _dbus_watch_unref (socket_server->watch[i]);
241  socket_server->watch[i] = NULL;
242  }
243 
244  if (_dbus_socket_is_valid (socket_server->fds[i]))
245  {
246  _dbus_close_socket (socket_server->fds[i], NULL);
247  _dbus_socket_invalidate (&socket_server->fds[i]);
248  }
249  }
250 
251  if (socket_server->socket_name != NULL)
252  {
253  DBusString tmp;
254  _dbus_string_init_const (&tmp, socket_server->socket_name);
255  _dbus_delete_file (&tmp, NULL);
256  }
257 
258  if (server->published_address)
259  _dbus_daemon_unpublish_session_bus_address();
260 
261  HAVE_LOCK_CHECK (server);
262 }
263 
264 static const DBusServerVTable socket_vtable = {
265  socket_finalize,
266  socket_disconnect
267 };
268 
285 DBusServer*
287  int n_fds,
288  const DBusString *address,
290  DBusError *error)
291 {
292  DBusServerSocket *socket_server;
293  DBusServer *server;
294  int i;
295 
296  socket_server = dbus_new0 (DBusServerSocket, 1);
297  if (socket_server == NULL)
298  goto failed;
299 
300  socket_server->noncefile = noncefile;
301 
302  socket_server->fds = dbus_new (DBusSocket, n_fds);
303  if (!socket_server->fds)
304  goto failed;
305 
306  socket_server->watch = dbus_new0 (DBusWatch *, n_fds);
307  if (!socket_server->watch)
308  goto failed;
309 
310  for (i = 0 ; i < n_fds ; i++)
311  {
312  DBusWatch *watch;
313 
314  watch = _dbus_watch_new (_dbus_socket_get_pollable (fds[i]),
316  TRUE,
317  socket_handle_watch, socket_server,
318  NULL);
319  if (watch == NULL)
320  goto failed;
321 
322  socket_server->n_fds++;
323  socket_server->fds[i] = fds[i];
324  socket_server->watch[i] = watch;
325  }
326 
327  if (!_dbus_server_init_base (&socket_server->base,
328  &socket_vtable, address,
329  error))
330  goto failed;
331 
332  server = (DBusServer*)socket_server;
333 
334  SERVER_LOCK (server);
335 
336  for (i = 0 ; i < n_fds ; i++)
337  {
338  if (!_dbus_server_add_watch (&socket_server->base,
339  socket_server->watch[i]))
340  {
341  int j;
342 
343  /* The caller is still responsible for closing the fds until
344  * we return successfully, so don't let socket_disconnect()
345  * close them */
346  for (j = 0; j < n_fds; j++)
347  _dbus_socket_invalidate (&socket_server->fds[j]);
348 
349  /* socket_disconnect() will try to remove all the watches;
350  * make sure it doesn't see the ones that weren't even added
351  * yet */
352  for (j = i; j < n_fds; j++)
353  {
354  _dbus_watch_invalidate (socket_server->watch[j]);
355  _dbus_watch_unref (socket_server->watch[j]);
356  socket_server->watch[j] = NULL;
357  }
358 
359  _dbus_server_disconnect_unlocked (server);
360  SERVER_UNLOCK (server);
361  _dbus_server_finalize_base (&socket_server->base);
362  goto failed;
363  }
364  }
365 
366  SERVER_UNLOCK (server);
367 
368  _dbus_server_trace_ref (&socket_server->base, 0, 1, "new_for_socket");
369  return (DBusServer*) socket_server;
370 
371 failed:
372  if (socket_server != NULL)
373  {
374  if (socket_server->watch != NULL)
375  {
376  for (i = 0; i < n_fds; i++)
377  {
378  if (socket_server->watch[i] != NULL)
379  {
380  _dbus_watch_invalidate (socket_server->watch[i]);
381  _dbus_watch_unref (socket_server->watch[i]);
382  socket_server->watch[i] = NULL;
383  }
384  }
385  }
386 
387  dbus_free (socket_server->watch);
388  dbus_free (socket_server->fds);
389  dbus_free (socket_server);
390  }
391 
392  if (error != NULL && !dbus_error_is_set (error))
393  _DBUS_SET_OOM (error);
394 
395  return NULL;
396 }
397 
417 DBusServer*
419  const char *bind,
420  const char *port,
421  const char *family,
422  DBusError *error,
423  dbus_bool_t use_nonce)
424 {
425  DBusServer *server = NULL;
426  DBusSocket *listen_fds = NULL;
427  int nlisten_fds = 0, i;
428  DBusString address = _DBUS_STRING_INIT_INVALID;
429  DBusString host_str; /* Initialized as const later, not freed */
430  DBusString port_str = _DBUS_STRING_INIT_INVALID;
432  const char *family_used = NULL;
433 
434  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
435 
436  if (!_dbus_string_init (&address))
437  {
439  goto failed;
440  }
441 
442  if (!_dbus_string_init (&port_str))
443  {
445  goto failed;
446  }
447 
448  if (host == NULL)
449  host = "localhost";
450 
451  if (port == NULL)
452  port = "0";
453 
454  if (bind == NULL)
455  bind = host;
456  else if (strcmp (bind, "*") == 0)
457  bind = NULL;
458 
459  nlisten_fds =_dbus_listen_tcp_socket (bind, port, family,
460  &port_str,
461  &family_used,
462  &listen_fds, error);
463  if (nlisten_fds <= 0)
464  {
465  _DBUS_ASSERT_ERROR_IS_SET(error);
466  goto failed;
467  }
468 
469  _dbus_string_init_const (&host_str, host);
470  if (!_dbus_string_append (&address, use_nonce ? "nonce-tcp:host=" : "tcp:host=") ||
471  !_dbus_address_append_escaped (&address, &host_str) ||
472  !_dbus_string_append (&address, ",port=") ||
473  !_dbus_string_append (&address, _dbus_string_get_const_data(&port_str)))
474  {
476  goto failed;
477  }
478  if (family_used &&
479  (!_dbus_string_append (&address, ",family=") ||
480  !_dbus_string_append (&address, family_used)))
481  {
483  goto failed;
484  }
485 
486  if (use_nonce)
487  {
488  if (!_dbus_noncefile_create (&noncefile, error))
489  goto failed;
490 
491  if (!_dbus_string_append (&address, ",noncefile=") ||
492  !_dbus_address_append_escaped (&address, _dbus_noncefile_get_path (noncefile)))
493  {
495  goto failed;
496  }
497  }
498 
499  server = _dbus_server_new_for_socket (listen_fds, nlisten_fds, &address, noncefile, error);
500  if (server == NULL)
501  goto failed;
502 
503  /* server has taken ownership of noncefile and the fds in listen_fds */
504  _dbus_string_free (&port_str);
505  _dbus_string_free (&address);
506  dbus_free(listen_fds);
507 
508  return server;
509 
510 failed:
511  _dbus_noncefile_delete (&noncefile, NULL);
512 
513  if (listen_fds != NULL)
514  {
515  for (i = 0; i < nlisten_fds; i++)
516  _dbus_close_socket (listen_fds[i], NULL);
517  dbus_free (listen_fds);
518  }
519 
520  _dbus_string_free (&port_str);
521  _dbus_string_free (&address);
522  return NULL;
523 }
524 
537 DBusServerListenResult
539  DBusServer **server_p,
540  DBusError *error)
541 {
542  const char *method;
543 
544  *server_p = NULL;
545 
546  method = dbus_address_entry_get_method (entry);
547 
548  if (strcmp (method, "tcp") == 0 || strcmp (method, "nonce-tcp") == 0)
549  {
550  const char *host;
551  const char *port;
552  const char *bind;
553  const char *family;
554 
555  host = dbus_address_entry_get_value (entry, "host");
556  bind = dbus_address_entry_get_value (entry, "bind");
557  port = dbus_address_entry_get_value (entry, "port");
558  family = dbus_address_entry_get_value (entry, "family");
559 
560  *server_p = _dbus_server_new_for_tcp_socket (host, bind, port,
561  family, error, strcmp (method, "nonce-tcp") == 0 ? TRUE : FALSE);
562 
563  if (*server_p)
564  {
565  _DBUS_ASSERT_ERROR_IS_CLEAR(error);
566  return DBUS_SERVER_LISTEN_OK;
567  }
568  else
569  {
570  _DBUS_ASSERT_ERROR_IS_SET(error);
571  return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
572  }
573  }
574  else
575  {
576  _DBUS_ASSERT_ERROR_IS_CLEAR(error);
577  return DBUS_SERVER_LISTEN_NOT_HANDLED;
578  }
579 }
580 
590 void
592  char *filename)
593 {
594  DBusServerSocket *socket_server = (DBusServerSocket*) server;
595 
596  socket_server->socket_name = filename;
597 }
598 
599 
dbus_bool_t _dbus_string_append(DBusString *str, const char *buffer)
Appends a nul-terminated C-style string to a DBusString.
Definition: dbus-string.c:952
dbus_bool_t _dbus_server_add_watch(DBusServer *server, DBusWatch *watch)
Adds a watch for this server, chaining out to application-provided watch handlers.
Definition: dbus-server.c:296
DBusWatch * _dbus_watch_new(DBusPollable fd, unsigned int flags, dbus_bool_t enabled, DBusWatchHandler handler, void *data, DBusFreeFunction free_data_function)
Creates a new DBusWatch.
Definition: dbus-watch.c:88
DBusNonceFile * noncefile
Nonce file used to authenticate clients.
Implementation of DBusWatch.
Definition: dbus-watch.c:40
#define NULL
A null pointer, defined appropriately for C or C++.
void dbus_free(void *memory)
Frees a block of memory previously allocated by dbus_malloc() or dbus_malloc0().
Definition: dbus-memory.c:703
#define dbus_new(type, count)
Safe macro for using dbus_malloc().
Definition: dbus-memory.h:57
Internals of DBusServer object.
#define _dbus_assert(condition)
Aborts with an error message if the condition is false.
const char * dbus_address_entry_get_method(DBusAddressEntry *entry)
Returns the method string of an address entry.
Definition: dbus-address.c:228
void _dbus_connection_close_if_only_one_ref(DBusConnection *connection)
Used internally to handle the semantics of dbus_server_set_new_connection_function().
Implementation details of DBusConnection.
dbus_bool_t _dbus_string_init(DBusString *str)
Initializes a string.
Definition: dbus-string.c:175
DBUS_PRIVATE_EXPORT void _dbus_server_ref_unlocked(DBusServer *server)
Like dbus_server_ref() but does not acquire the lock (must already be held)
Definition: dbus-server.c:456
void(* DBusNewConnectionFunction)(DBusServer *server, DBusConnection *new_connection, void *data)
Called when a new connection to the server is available.
Definition: dbus-server.h:48
DBusNewConnectionFunction new_connection_function
Callback to invoke when a new connection is created.
dbus_bool_t _dbus_close_socket(DBusSocket fd, DBusError *error)
Closes a socket.
DBusServer * _dbus_server_new_for_tcp_socket(const char *host, const char *bind, const char *port, const char *family, DBusError *error, dbus_bool_t use_nonce)
Creates a new server listening on TCP.
char ** auth_mechanisms
Array of allowed authentication mechanisms.
dbus_bool_t _dbus_delete_file(const DBusString *filename, DBusError *error)
Deletes the given file.
dbus_bool_t _dbus_transport_set_auth_mechanisms(DBusTransport *transport, const char **mechanisms)
Sets the SASL authentication mechanisms supported by this transport.
DBusServer * _dbus_server_new_for_socket(DBusSocket *fds, int n_fds, const DBusString *address, DBusNonceFile *noncefile, DBusError *error)
Creates a new server listening on the given file descriptor.
Socket interface.
Definition: dbus-sysdeps.h:178
const char * dbus_address_entry_get_value(DBusAddressEntry *entry, const char *key)
Returns a value from a key of an entry.
Definition: dbus-address.c:245
Implementation details of DBusServerSocket.
DBusTransport * _dbus_transport_new_for_socket(DBusSocket fd, const DBusString *server_guid, const DBusString *address)
Creates a new transport for the given socket file descriptor.
#define dbus_new0(type, count)
Safe macro for using dbus_malloc0().
Definition: dbus-memory.h:58
dbus_bool_t _dbus_get_is_errno_eagain_or_ewouldblock(int e)
See if errno is EAGAIN or EWOULDBLOCK (this has to be done differently for Winsock so is abstracted) ...
dbus_uint32_t dbus_bool_t
A boolean, valid values are TRUE and FALSE.
Definition: dbus-types.h:35
void _dbus_string_init_const(DBusString *str, const char *value)
Initializes a constant string.
Definition: dbus-string.c:190
void _dbus_server_socket_own_filename(DBusServer *server, char *filename)
This is a bad hack since it&#39;s really unix domain socket specific.
DBusSocket _dbus_accept(DBusSocket listen_fd)
Accepts a connection on a listening socket.
Internals of DBusAddressEntry.
Definition: dbus-address.c:44
void _dbus_server_remove_watch(DBusServer *server, DBusWatch *watch)
Removes a watch previously added with _dbus_server_remove_watch().
Definition: dbus-server.c:312
void _dbus_watch_invalidate(DBusWatch *watch)
Clears the file descriptor from a now-invalid watch object so that no one tries to use it...
Definition: dbus-watch.c:169
Object representing an exception.
Definition: dbus-errors.h:48
dbus_bool_t _dbus_address_append_escaped(DBusString *escaped, const DBusString *unescaped)
Appends an escaped version of one string to another string, using the D-Bus address escaping mechanis...
Definition: dbus-address.c:105
DBusSocket * fds
File descriptor or DBUS_SOCKET_INVALID if disconnected.
void dbus_set_error(DBusError *error, const char *name, const char *format,...)
Assigns an error name and message to a DBusError.
Definition: dbus-errors.c:354
void _dbus_server_finalize_base(DBusServer *server)
Finalizes the members of the DBusServer base class.
Definition: dbus-server.c:201
Virtual table to be implemented by all server "subclasses".
void dbus_server_unref(DBusServer *server)
Decrements the reference count of a DBusServer.
Definition: dbus-server.c:733
As in POLLERR (can&#39;t watch for this, but can be present in current state passed to dbus_watch_handle(...
DBusConnection * _dbus_connection_new_for_transport(DBusTransport *transport)
Creates a new connection for the given transport.
void _dbus_string_free(DBusString *str)
Frees a string created by _dbus_string_init(), and fills it with the same contents as #_DBUS_STRING_I...
Definition: dbus-string.c:264
#define TRUE
Expands to "1".
As in POLLHUP (can&#39;t watch for it, but can be present in current state passed to dbus_watch_handle())...
dbus_bool_t published_address
flag which indicates that server has published its bus address.
Object representing a transport such as a socket.
void * new_connection_data
Data for new connection callback.
DBusServerListenResult _dbus_server_listen_socket(DBusAddressEntry *entry, DBusServer **server_p, DBusError *error)
Tries to interpret the address entry for various socket-related addresses (well, currently only tcp a...
DBusServer base
Parent class members.
dbus_bool_t _dbus_server_init_base(DBusServer *server, const DBusServerVTable *vtable, const DBusString *address, DBusError *error)
Initializes the members of the DBusServer base class.
Definition: dbus-server.c:112
char * socket_name
Name of domain socket, to unlink if appropriate.
void _dbus_watch_unref(DBusWatch *watch)
Decrements the reference count of a DBusWatch object and finalizes the object if the count reaches ze...
Definition: dbus-watch.c:138
dbus_bool_t _dbus_set_socket_nonblocking(DBusSocket fd, DBusError *error)
Sets a file descriptor to be nonblocking.
DBusString guid_hex
Hex-encoded version of GUID.
#define DBUS_ERROR_NO_MEMORY
There was not enough memory to complete an operation.
#define FALSE
Expands to "0".
int n_fds
Number of active file handles.
As in POLLIN.
void dbus_connection_unref(DBusConnection *connection)
Decrements the reference count of a DBusConnection, and finalizes it if the count reaches zero...
int _dbus_listen_tcp_socket(const char *host, const char *port, const char *family, DBusString *retport, const char **retfamily, DBusSocket **fds_p, DBusError *error)
Creates a socket and binds it to the given path, then listens on the socket.
dbus_bool_t dbus_error_is_set(const DBusError *error)
Checks whether an error occurred (the error is set).
Definition: dbus-errors.c:329
void _dbus_transport_unref(DBusTransport *transport)
Decrements the reference count for the transport.
DBusWatch ** watch
File descriptor watch.