D-Bus  1.4.16
dbus-server-socket.c
00001 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
00002 /* dbus-server-socket.c Server implementation for sockets
00003  *
00004  * Copyright (C) 2002, 2003, 2004, 2006  Red Hat Inc.
00005  *
00006  * Licensed under the Academic Free License version 2.1
00007  *
00008  * This program is free software; you can redistribute it and/or modify
00009  * it under the terms of the GNU General Public License as published by
00010  * the Free Software Foundation; either version 2 of the License, or
00011  * (at your option) any later version.
00012  *
00013  * This program is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00016  * GNU General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU General Public License
00019  * along with this program; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
00021  *
00022  */
00023 
00024 #include <config.h>
00025 #include "dbus-internals.h"
00026 #include "dbus-server-socket.h"
00027 #include "dbus-transport-socket.h"
00028 #include "dbus-connection-internal.h"
00029 #include "dbus-memory.h"
00030 #include "dbus-nonce.h"
00031 #include "dbus-string.h"
00032 
00044 typedef struct DBusServerSocket DBusServerSocket;
00045 
00050 struct DBusServerSocket
00051 {
00052   DBusServer base;   
00053   int n_fds;         
00054   int *fds;          
00055   DBusWatch **watch; 
00056   char *socket_name; 
00057   DBusNonceFile *noncefile; 
00058 };
00059 
00060 static void
00061 socket_finalize (DBusServer *server)
00062 {
00063   DBusServerSocket *socket_server = (DBusServerSocket*) server;
00064   int i;
00065 
00066   _dbus_server_finalize_base (server);
00067 
00068   for (i = 0 ; i < socket_server->n_fds ; i++)
00069     if (socket_server->watch[i])
00070       {
00071         _dbus_watch_unref (socket_server->watch[i]);
00072         socket_server->watch[i] = NULL;
00073       }
00074 
00075   dbus_free (socket_server->fds);
00076   dbus_free (socket_server->watch);
00077   dbus_free (socket_server->socket_name);
00078   if (socket_server->noncefile)
00079         _dbus_noncefile_delete (socket_server->noncefile, NULL);
00080   dbus_free (socket_server->noncefile);
00081   dbus_free (server);
00082 }
00083 
00084 /* Return value is just for memory, not other failures. */
00085 static dbus_bool_t
00086 handle_new_client_fd_and_unlock (DBusServer *server,
00087                                  int         client_fd)
00088 {
00089   DBusConnection *connection;
00090   DBusTransport *transport;
00091   DBusNewConnectionFunction new_connection_function;
00092   DBusServerSocket* socket_server;
00093   void *new_connection_data;
00094 
00095   socket_server = (DBusServerSocket*)server;
00096   _dbus_verbose ("Creating new client connection with fd %d\n", client_fd);
00097 
00098   HAVE_LOCK_CHECK (server);
00099 
00100   if (!_dbus_set_fd_nonblocking (client_fd, NULL))
00101     {
00102       SERVER_UNLOCK (server);
00103       return TRUE;
00104     }
00105 
00106   transport = _dbus_transport_new_for_socket (client_fd, &server->guid_hex, FALSE);
00107   if (transport == NULL)
00108     {
00109       _dbus_close_socket (client_fd, NULL);
00110       SERVER_UNLOCK (server);
00111       return FALSE;
00112     }
00113 
00114   if (!_dbus_transport_set_auth_mechanisms (transport,
00115                                             (const char **) server->auth_mechanisms))
00116     {
00117       _dbus_transport_unref (transport);
00118       SERVER_UNLOCK (server);
00119       return FALSE;
00120     }
00121 
00122   /* note that client_fd is now owned by the transport, and will be
00123    * closed on transport disconnection/finalization
00124    */
00125 
00126   connection = _dbus_connection_new_for_transport (transport);
00127   _dbus_transport_unref (transport);
00128   transport = NULL; /* now under the connection lock */
00129 
00130   if (connection == NULL)
00131     {
00132       SERVER_UNLOCK (server);
00133       return FALSE;
00134     }
00135 
00136   /* See if someone wants to handle this new connection, self-referencing
00137    * for paranoia.
00138    */
00139   new_connection_function = server->new_connection_function;
00140   new_connection_data = server->new_connection_data;
00141 
00142   _dbus_server_ref_unlocked (server);
00143   SERVER_UNLOCK (server);
00144 
00145   if (new_connection_function)
00146     {
00147       (* new_connection_function) (server, connection,
00148                                    new_connection_data);
00149     }
00150   dbus_server_unref (server);
00151 
00152   /* If no one grabbed a reference, the connection will die. */
00153   _dbus_connection_close_if_only_one_ref (connection);
00154   dbus_connection_unref (connection);
00155 
00156   return TRUE;
00157 }
00158 
00159 static dbus_bool_t
00160 socket_handle_watch (DBusWatch    *watch,
00161                    unsigned int  flags,
00162                    void         *data)
00163 {
00164   DBusServer *server = data;
00165   DBusServerSocket *socket_server = data;
00166 
00167 #ifndef DBUS_DISABLE_ASSERT
00168   int i;
00169   dbus_bool_t found = FALSE;
00170 #endif
00171 
00172   SERVER_LOCK (server);
00173 
00174 #ifndef DBUS_DISABLE_ASSERT
00175   for (i = 0 ; i < socket_server->n_fds ; i++)
00176     {
00177       if (socket_server->watch[i] == watch)
00178         found = TRUE;
00179     }
00180   _dbus_assert (found);
00181 #endif
00182 
00183   _dbus_verbose ("Handling client connection, flags 0x%x\n", flags);
00184 
00185   if (flags & DBUS_WATCH_READABLE)
00186     {
00187       int client_fd;
00188       int listen_fd;
00189 
00190       listen_fd = dbus_watch_get_socket (watch);
00191 
00192       if (socket_server->noncefile)
00193           client_fd = _dbus_accept_with_noncefile (listen_fd, socket_server->noncefile);
00194       else 
00195           client_fd = _dbus_accept (listen_fd);
00196 
00197       if (client_fd < 0)
00198         {
00199           /* EINTR handled for us */
00200 
00201           if (_dbus_get_is_errno_eagain_or_ewouldblock ())
00202             _dbus_verbose ("No client available to accept after all\n");
00203           else
00204             _dbus_verbose ("Failed to accept a client connection: %s\n",
00205                            _dbus_strerror_from_errno ());
00206 
00207           SERVER_UNLOCK (server);
00208         }
00209       else
00210         {
00211           if (!handle_new_client_fd_and_unlock (server, client_fd))
00212             _dbus_verbose ("Rejected client connection due to lack of memory\n");
00213         }
00214     }
00215 
00216   if (flags & DBUS_WATCH_ERROR)
00217     _dbus_verbose ("Error on server listening socket\n");
00218 
00219   if (flags & DBUS_WATCH_HANGUP)
00220     _dbus_verbose ("Hangup on server listening socket\n");
00221 
00222   return TRUE;
00223 }
00224 
00225 static void
00226 socket_disconnect (DBusServer *server)
00227 {
00228   DBusServerSocket *socket_server = (DBusServerSocket*) server;
00229   int i;
00230 
00231   HAVE_LOCK_CHECK (server);
00232 
00233   for (i = 0 ; i < socket_server->n_fds ; i++)
00234     {
00235       if (socket_server->watch[i])
00236         {
00237           _dbus_server_remove_watch (server,
00238                                      socket_server->watch[i]);
00239           _dbus_watch_unref (socket_server->watch[i]);
00240           socket_server->watch[i] = NULL;
00241         }
00242 
00243       _dbus_close_socket (socket_server->fds[i], NULL);
00244       socket_server->fds[i] = -1;
00245     }
00246 
00247   if (socket_server->socket_name != NULL)
00248     {
00249       DBusString tmp;
00250       _dbus_string_init_const (&tmp, socket_server->socket_name);
00251       _dbus_delete_file (&tmp, NULL);
00252     }
00253 
00254   if (server->published_address)
00255       _dbus_daemon_unpublish_session_bus_address();
00256 
00257   HAVE_LOCK_CHECK (server);
00258 }
00259 
00260 static const DBusServerVTable socket_vtable = {
00261   socket_finalize,
00262   socket_disconnect
00263 };
00264 
00280 DBusServer*
00281 _dbus_server_new_for_socket (int              *fds,
00282                              int               n_fds,
00283                              const DBusString *address,
00284                              DBusNonceFile    *noncefile)
00285 {
00286   DBusServerSocket *socket_server;
00287   DBusServer *server;
00288   int i;
00289 
00290   socket_server = dbus_new0 (DBusServerSocket, 1);
00291   if (socket_server == NULL)
00292     return NULL;
00293 
00294   socket_server->noncefile = noncefile;
00295 
00296   socket_server->fds = dbus_new (int, n_fds);
00297   if (!socket_server->fds)
00298     goto failed_0;
00299 
00300   socket_server->watch = dbus_new0 (DBusWatch *, n_fds);
00301   if (!socket_server->watch)
00302     goto failed_1;
00303 
00304   for (i = 0 ; i < n_fds ; i++)
00305     {
00306       DBusWatch *watch;
00307 
00308       watch = _dbus_watch_new (fds[i],
00309                                DBUS_WATCH_READABLE,
00310                                TRUE,
00311                                socket_handle_watch, socket_server,
00312                                NULL);
00313       if (watch == NULL)
00314         goto failed_2;
00315 
00316       socket_server->n_fds++;
00317       socket_server->fds[i] = fds[i];
00318       socket_server->watch[i] = watch;
00319     }
00320 
00321   if (!_dbus_server_init_base (&socket_server->base,
00322                                &socket_vtable, address))
00323     goto failed_2;
00324 
00325   server = (DBusServer*)socket_server;
00326 
00327   SERVER_LOCK (server);
00328 
00329   for (i = 0 ; i < n_fds ; i++)
00330     {
00331       if (!_dbus_server_add_watch (&socket_server->base,
00332                                    socket_server->watch[i]))
00333         {
00334           int j;
00335           for (j = 0 ; j < i ; j++)
00336             _dbus_server_remove_watch (server,
00337                                        socket_server->watch[j]);
00338 
00339           SERVER_UNLOCK (server);
00340           _dbus_server_finalize_base (&socket_server->base);
00341           goto failed_2;
00342         }
00343     }
00344 
00345   SERVER_UNLOCK (server);
00346 
00347   return (DBusServer*) socket_server;
00348 
00349  failed_2:
00350   for (i = 0 ; i < n_fds ; i++)
00351     {
00352       if (socket_server->watch[i] != NULL)
00353         {
00354           _dbus_watch_unref (socket_server->watch[i]);
00355           socket_server->watch[i] = NULL;
00356         }
00357     }
00358   dbus_free (socket_server->watch);
00359 
00360  failed_1:
00361   dbus_free (socket_server->fds);
00362 
00363  failed_0:
00364   dbus_free (socket_server);
00365   return NULL;
00366 }
00367 
00387 DBusServer*
00388 _dbus_server_new_for_tcp_socket (const char     *host,
00389                                  const char     *bind,
00390                                  const char     *port,
00391                                  const char     *family,
00392                                  DBusError      *error,
00393                                  dbus_bool_t    use_nonce)
00394 {
00395   DBusServer *server;
00396   int *listen_fds = NULL;
00397   int nlisten_fds = 0, i;
00398   DBusString address;
00399   DBusString host_str;
00400   DBusString port_str;
00401   DBusNonceFile *noncefile;
00402   
00403   _DBUS_ASSERT_ERROR_IS_CLEAR (error);
00404 
00405   noncefile = NULL;
00406 
00407   if (!_dbus_string_init (&address))
00408     {
00409       dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
00410       return NULL;
00411     }
00412 
00413   if (!_dbus_string_init (&port_str))
00414     {
00415       dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
00416       goto failed_0;
00417     }
00418 
00419   if (host == NULL)
00420     host = "localhost";
00421 
00422   if (port == NULL)
00423     port = "0";
00424 
00425   if (bind == NULL)
00426     bind = host;
00427   else if (strcmp (bind, "*") == 0)
00428     bind = NULL;
00429 
00430   nlisten_fds =_dbus_listen_tcp_socket (bind, port, family,
00431                                         &port_str,
00432                                         &listen_fds, error);
00433   if (nlisten_fds <= 0)
00434     {
00435       _DBUS_ASSERT_ERROR_IS_SET(error);
00436       goto failed_1;
00437     }
00438 
00439   _dbus_string_init_const (&host_str, host);
00440   if (!_dbus_string_append (&address, use_nonce ? "nonce-tcp:host=" : "tcp:host=") ||
00441       !_dbus_address_append_escaped (&address, &host_str) ||
00442       !_dbus_string_append (&address, ",port=") ||
00443       !_dbus_string_append (&address, _dbus_string_get_const_data(&port_str)))
00444     {
00445       dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
00446       goto failed_2;
00447     }
00448   if (family &&
00449       (!_dbus_string_append (&address, ",family=") ||
00450        !_dbus_string_append (&address, family)))
00451     {
00452       dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
00453       goto failed_2;
00454     }
00455 
00456   if (use_nonce)
00457     {
00458       noncefile = dbus_new0 (DBusNonceFile, 1);
00459       if (noncefile == NULL)
00460         {
00461           dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
00462           goto failed_2;
00463         }
00464 
00465       if (!_dbus_noncefile_create (noncefile, error))
00466           goto failed_3;
00467 
00468       if (!_dbus_string_append (&address, ",noncefile=") ||
00469           !_dbus_address_append_escaped (&address, _dbus_noncefile_get_path (noncefile)))
00470         {
00471           dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
00472           goto failed_4;
00473         }
00474 
00475     }
00476 
00477   server = _dbus_server_new_for_socket (listen_fds, nlisten_fds, &address, noncefile);
00478   if (server == NULL)
00479     {
00480       dbus_set_error (error, DBUS_ERROR_NO_MEMORY, NULL);
00481       goto failed_4;
00482     }
00483 
00484   _dbus_string_free (&port_str);
00485   _dbus_string_free (&address);
00486   dbus_free(listen_fds);
00487 
00488   return server;
00489 
00490  failed_4:
00491   _dbus_noncefile_delete (noncefile, NULL);
00492 
00493  failed_3:
00494   dbus_free (noncefile);
00495 
00496  failed_2:
00497   for (i = 0 ; i < nlisten_fds ; i++)
00498     _dbus_close_socket (listen_fds[i], NULL);
00499   dbus_free(listen_fds);
00500 
00501  failed_1:
00502   _dbus_string_free (&port_str);
00503 
00504  failed_0:
00505   _dbus_string_free (&address);
00506 
00507   return NULL;
00508 }
00509 
00522 DBusServerListenResult
00523 _dbus_server_listen_socket (DBusAddressEntry *entry,
00524                             DBusServer      **server_p,
00525                             DBusError        *error)
00526 {
00527   const char *method;
00528 
00529   *server_p = NULL;
00530 
00531   method = dbus_address_entry_get_method (entry);
00532 
00533   if (strcmp (method, "tcp") == 0 || strcmp (method, "nonce-tcp") == 0)
00534     {
00535       const char *host;
00536       const char *port;
00537       const char *bind;
00538       const char *family;
00539 
00540       host = dbus_address_entry_get_value (entry, "host");
00541       bind = dbus_address_entry_get_value (entry, "bind");
00542       port = dbus_address_entry_get_value (entry, "port");
00543       family = dbus_address_entry_get_value (entry, "family");
00544 
00545       *server_p = _dbus_server_new_for_tcp_socket (host, bind, port,
00546                                                    family, error, strcmp (method, "nonce-tcp") == 0 ? TRUE : FALSE);
00547 
00548       if (*server_p)
00549         {
00550           _DBUS_ASSERT_ERROR_IS_CLEAR(error);
00551           return DBUS_SERVER_LISTEN_OK;
00552         }
00553       else
00554         {
00555           _DBUS_ASSERT_ERROR_IS_SET(error);
00556           return DBUS_SERVER_LISTEN_DID_NOT_CONNECT;
00557         }
00558     }
00559   else
00560     {
00561       _DBUS_ASSERT_ERROR_IS_CLEAR(error);
00562       return DBUS_SERVER_LISTEN_NOT_HANDLED;
00563     }
00564 }
00565 
00575 void
00576 _dbus_server_socket_own_filename (DBusServer *server,
00577                                   char       *filename)
00578 {
00579   DBusServerSocket *socket_server = (DBusServerSocket*) server;
00580 
00581   socket_server->socket_name = filename;
00582 }
00583 
00584