Esempio n. 1
0
/**
 * Removes a link from the list. This is a constant-time operation.
 *
 * @param list address of the list head.
 * @param link the list link to remove.
 */
void
_dbus_list_remove_link (DBusList **list,
                        DBusList  *link)
{
  _dbus_list_unlink (list, link);
  free_link (link);
}
Esempio n. 2
0
/**
 * Removes the last link in the list and returns it.  This is a
 * constant-time operation.
 *
 * @param list address of the list head.
 * @returns the last link in the list, or #NULL for an empty list.
 */
DBusList*
_dbus_list_pop_last_link (DBusList **list)
{
  DBusList *link;
  
  link = _dbus_list_get_last_link (list);
  if (link == NULL)
    return NULL;

  _dbus_list_unlink (list, link);

  return link;
}
Esempio n. 3
0
EXPORT_C
#endif
DBusList*
_dbus_list_pop_first_link (DBusList **list)
{
  DBusList *link;
  
  link = _dbus_list_get_first_link (list);
  if (link == NULL)
    return NULL;

  _dbus_list_unlink (list, link);

  return link;
}
Esempio n. 4
0
/* this function is self-cancelling if you cancel the transaction */
dbus_bool_t
bus_service_add_owner (BusService     *service,
                       DBusConnection *connection,
                       dbus_uint32_t  flags,
                       BusTransaction *transaction,
                       DBusError      *error)
{
  BusOwner *bus_owner;
  DBusList *bus_owner_link;
  
  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
  
 /* Send service acquired message first, OOM will result
  * in cancelling the transaction
  */
  if (service->owners == NULL)
    {
      if (!bus_driver_send_service_acquired (connection, service->name, transaction, error))
        return FALSE;
    }
  
  bus_owner_link = _bus_service_find_owner_link (service, connection);
  
  if (bus_owner_link == NULL)
    {
      bus_owner = bus_owner_new (service, connection, flags);
      if (bus_owner == NULL)
        {
          BUS_SET_OOM (error);
          return FALSE;
        }

      bus_owner_set_flags (bus_owner, flags);
      if (!(flags & DBUS_NAME_FLAG_REPLACE_EXISTING) || service->owners == NULL)
        {
          if (!_dbus_list_append (&service->owners,
                                  bus_owner))
            {
              bus_owner_unref (bus_owner);
              BUS_SET_OOM (error);
              return FALSE;
            }
        }
      else
        {
          if (!_dbus_list_insert_after (&service->owners,
                                         _dbus_list_get_first_link (&service->owners),
                                         bus_owner))
            {
              bus_owner_unref (bus_owner);
              BUS_SET_OOM (error);
              return FALSE;
            }
        }      
    } 
  else 
    {
      /* Update the link since we are already in the queue
       * No need for operations that can produce OOM
       */

      bus_owner = (BusOwner *) bus_owner_link->data;
      if (flags & DBUS_NAME_FLAG_REPLACE_EXISTING)
        {
	  DBusList *link;
          _dbus_list_unlink (&service->owners, bus_owner_link);
	  link = _dbus_list_get_first_link (&service->owners);
	  _dbus_assert (link != NULL);
	  
          _dbus_list_insert_after_link (&service->owners, link, bus_owner_link);
        }
      
      bus_owner_set_flags (bus_owner, flags);
      return TRUE;
    }

  if (!add_cancel_ownership_to_transaction (transaction,
                                            service,
                                            bus_owner))
    {
      bus_service_unlink_owner (service, bus_owner);
      BUS_SET_OOM (error);
      return FALSE;
    }

  return TRUE;
}
Esempio n. 5
0
dbus_bool_t
bus_registry_acquire_service (BusRegistry      *registry,
                              DBusConnection   *connection,
                              const DBusString *service_name,
                              dbus_uint32_t     flags,
                              dbus_uint32_t    *result,
                              BusTransaction   *transaction,
                              DBusError        *error)
{
  dbus_bool_t retval;
  DBusConnection *old_owner_conn;
  BusClientPolicy *policy;
  BusService *service;
  BusActivation  *activation;
  BusSELinuxID *sid;
  BusOwner *primary_owner;
 
  retval = FALSE;

  if (!_dbus_validate_bus_name (service_name, 0,
                                _dbus_string_get_length (service_name)))
    {
      dbus_set_error (error, DBUS_ERROR_INVALID_ARGS,
                      "Requested bus name \"%s\" is not valid",
                      _dbus_string_get_const_data (service_name));
      
      _dbus_verbose ("Attempt to acquire invalid service name\n");
      
      goto out;
    }
  
  if (_dbus_string_get_byte (service_name, 0) == ':')
    {
      /* Not allowed; only base services can start with ':' */
      dbus_set_error (error, DBUS_ERROR_INVALID_ARGS,
                      "Cannot acquire a service starting with ':' such as \"%s\"",
                      _dbus_string_get_const_data (service_name));
      
      _dbus_verbose ("Attempt to acquire invalid base service name \"%s\"",
                     _dbus_string_get_const_data (service_name));
      
      goto out;
    }

  if (_dbus_string_equal_c_str (service_name, DBUS_SERVICE_DBUS))
    {
      dbus_set_error (error, DBUS_ERROR_INVALID_ARGS,
                      "Connection \"%s\" is not allowed to own the service \"%s\"because "
                      "it is reserved for D-Bus' use only",
                      bus_connection_is_active (connection) ?
                      bus_connection_get_name (connection) :
                      "(inactive)",
                      DBUS_SERVICE_DBUS);
      goto out;
    }

  policy = bus_connection_get_policy (connection);
  _dbus_assert (policy != NULL);

  /* Note that if sid is #NULL then the bus's own context gets used
   * in bus_connection_selinux_allows_acquire_service()
   */
  sid = bus_selinux_id_table_lookup (registry->service_sid_table,
                                     service_name);

  if (!bus_selinux_allows_acquire_service (connection, sid,
					   _dbus_string_get_const_data (service_name), error))
    {

      if (dbus_error_is_set (error) &&
	  dbus_error_has_name (error, DBUS_ERROR_NO_MEMORY))
	{
	  goto out;
	}

      dbus_set_error (error, DBUS_ERROR_ACCESS_DENIED,
                      "Connection \"%s\" is not allowed to own the service \"%s\" due "
                      "to SELinux policy",
                      bus_connection_is_active (connection) ?
                      bus_connection_get_name (connection) :
                      "(inactive)",
                      _dbus_string_get_const_data (service_name));
      goto out;
    }
  
  if (!bus_client_policy_check_can_own (policy, service_name))
    {
      dbus_set_error (error, DBUS_ERROR_ACCESS_DENIED,
                      "Connection \"%s\" is not allowed to own the service \"%s\" due "
                      "to security policies in the configuration file",
                      bus_connection_is_active (connection) ?
                      bus_connection_get_name (connection) :
                      "(inactive)",
                      _dbus_string_get_const_data (service_name));
      goto out;
    }

  if (bus_connection_get_n_services_owned (connection) >=
      bus_context_get_max_services_per_connection (registry->context))
    {
      dbus_set_error (error, DBUS_ERROR_LIMITS_EXCEEDED,
                      "Connection \"%s\" is not allowed to own more services "
                      "(increase limits in configuration file if required)",
                      bus_connection_is_active (connection) ?
                      bus_connection_get_name (connection) :
                      "(inactive)");
      goto out;
    }
  
  service = bus_registry_lookup (registry, service_name);

  if (service != NULL)
    {
      primary_owner = bus_service_get_primary_owner (service);
      if (primary_owner != NULL)
        old_owner_conn = primary_owner->conn;
      else
        old_owner_conn = NULL;
    }
  else
    old_owner_conn = NULL;
      
  if (service == NULL)
    {
      service = bus_registry_ensure (registry,
                                     service_name, connection, flags,
                                     transaction, error);
      if (service == NULL)
        goto out;
    }

  primary_owner = bus_service_get_primary_owner (service);
  if (primary_owner == NULL)
    goto out;

  if (old_owner_conn == NULL)
    {
      _dbus_assert (primary_owner->conn == connection);

      *result = DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER;      
    }
  else if (old_owner_conn == connection)
    {
      bus_owner_set_flags (primary_owner, flags);
      *result = DBUS_REQUEST_NAME_REPLY_ALREADY_OWNER;
    }
  else if (((flags & DBUS_NAME_FLAG_DO_NOT_QUEUE) &&
           !(bus_service_get_allow_replacement (service))) ||
	   ((flags & DBUS_NAME_FLAG_DO_NOT_QUEUE) &&
           !(flags & DBUS_NAME_FLAG_REPLACE_EXISTING))) 
    {
      DBusList *link;
      BusOwner *temp_owner;
    /* Since we can't be queued if we are already in the queue
       remove us */

      link = _bus_service_find_owner_link (service, connection);
      if (link != NULL)
        {
          _dbus_list_unlink (&service->owners, link);
          temp_owner = (BusOwner *)link->data;
          bus_owner_unref (temp_owner); 
          _dbus_list_free_link (link);
        }
      
      *result = DBUS_REQUEST_NAME_REPLY_EXISTS;
    }
  else if (!(flags & DBUS_NAME_FLAG_DO_NOT_QUEUE) &&
           (!(flags & DBUS_NAME_FLAG_REPLACE_EXISTING) ||
	    !(bus_service_get_allow_replacement (service))))
    {
      /* Queue the connection */
      if (!bus_service_add_owner (service, connection, 
                                  flags,
                                  transaction, error))
        goto out;
      
      *result = DBUS_REQUEST_NAME_REPLY_IN_QUEUE;
    }
  else
    {
      /* Replace the current owner */

      /* We enqueue the new owner and remove the first one because
       * that will cause NameAcquired and NameLost messages to
       * be sent.
       */
      
      if (!bus_service_add_owner (service, connection,
                                  flags,
                                  transaction, error))
        goto out;

      if (primary_owner->do_not_queue)
        {
          if (!bus_service_remove_owner (service, old_owner_conn,
                                         transaction, error))
            goto out;
        }
      else
        {
          if (!bus_service_swap_owner (service, old_owner_conn,
                                       transaction, error))
            goto out;
        }
        
    
      _dbus_assert (connection == bus_service_get_primary_owner (service)->conn);
      *result = DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER;
    }

  activation = bus_context_get_activation (registry->context);
  retval = bus_activation_send_pending_auto_activation_messages (activation,
								 service,
								 transaction);
  if (!retval)
    BUS_SET_OOM (error);
  
 out:
  return retval;
}
Esempio n. 6
0
/* this function is self-cancelling if you cancel the transaction */
dbus_bool_t
bus_service_remove_owner (BusService     *service,
                          DBusConnection *connection,
                          BusTransaction *transaction,
                          DBusError      *error)
{
  BusOwner *primary_owner;
  
  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
  
  /* We send out notifications before we do any work we
   * might have to undo if the notification-sending failed
   */
  
  /* Send service lost message */
  primary_owner = bus_service_get_primary_owner (service);
  if (primary_owner != NULL && primary_owner->conn == connection)
    {
      if (!bus_driver_send_service_lost (connection, service->name,
                                         transaction, error))
        return FALSE;
    }
  else
    {
      /* if we are not the primary owner then just remove us from the queue */
      DBusList *link;
      BusOwner *temp_owner;

      link = _bus_service_find_owner_link (service, connection);
      _dbus_list_unlink (&service->owners, link);
      temp_owner = (BusOwner *)link->data;
      bus_owner_unref (temp_owner); 
      _dbus_list_free_link (link);

      return TRUE; 
    }

  if (service->owners == NULL)
    {
      _dbus_assert_not_reached ("Tried to remove owner of a service that has no owners");
    }
  else if (_dbus_list_length_is_one (&service->owners))
    {
      if (!bus_driver_send_service_owner_changed (service->name,
 						  bus_connection_get_name (connection),
 						  NULL,
 						  transaction, error))
        return FALSE;
    }
  else
    {
      DBusList *link;
      BusOwner *new_owner;
      DBusConnection *new_owner_conn;
      link = _dbus_list_get_first_link (&service->owners);
      _dbus_assert (link != NULL);
      link = _dbus_list_get_next_link (&service->owners, link);
      _dbus_assert (link != NULL);

      new_owner = (BusOwner *)link->data;
      new_owner_conn = new_owner->conn;

      if (!bus_driver_send_service_owner_changed (service->name,
 						  bus_connection_get_name (connection),
 						  bus_connection_get_name (new_owner_conn),
 						  transaction, error))
        return FALSE;

      /* This will be our new owner */
      if (!bus_driver_send_service_acquired (new_owner_conn,
                                             service->name,
                                             transaction,
                                             error))
        return FALSE;
    }

  if (!add_restore_ownership_to_transaction (transaction, service, primary_owner))
    {
      BUS_SET_OOM (error);
      return FALSE;
    }
 
  bus_service_unlink_owner (service, primary_owner);

  if (service->owners == NULL)
    bus_service_unlink (service);

  return TRUE;
}
Esempio n. 7
0
dbus_bool_t
bus_service_swap_owner (BusService     *service,
                        DBusConnection *connection,
                        BusTransaction *transaction,
                        DBusError      *error)
{
  DBusList *swap_link;
  BusOwner *primary_owner;

  _DBUS_ASSERT_ERROR_IS_CLEAR (error);

  /* We send out notifications before we do any work we
   * might have to undo if the notification-sending failed
   */
  
  /* Send service lost message */
  primary_owner = bus_service_get_primary_owner (service);
  if (primary_owner == NULL || primary_owner->conn != connection)
    _dbus_assert_not_reached ("Tried to swap a non primary owner");

    
  if (!bus_driver_send_service_lost (connection, service->name,
                                     transaction, error))
    return FALSE;

  if (service->owners == NULL)
    {
      _dbus_assert_not_reached ("Tried to swap owner of a service that has no owners");
    }
  else if (_dbus_list_length_is_one (&service->owners))
    {
      _dbus_assert_not_reached ("Tried to swap owner of a service that has no other owners in the queue");
    }
  else
    {
      DBusList *link;
      BusOwner *new_owner;
      DBusConnection *new_owner_conn;
      link = _dbus_list_get_first_link (&service->owners);
      _dbus_assert (link != NULL);
      link = _dbus_list_get_next_link (&service->owners, link);
      _dbus_assert (link != NULL);

      new_owner = (BusOwner *)link->data;
      new_owner_conn = new_owner->conn;

      if (!bus_driver_send_service_owner_changed (service->name,
 						  bus_connection_get_name (connection),
 						  bus_connection_get_name (new_owner_conn),
 						  transaction, error))
        return FALSE;

      /* This will be our new owner */
      if (!bus_driver_send_service_acquired (new_owner_conn,
                                             service->name,
                                             transaction,
                                             error))
        return FALSE;
    }

  if (!add_restore_ownership_to_transaction (transaction, service, primary_owner))
    {
      BUS_SET_OOM (error);
      return FALSE;
    }

  /* unlink the primary and make it the second link */
  swap_link = _dbus_list_get_first_link (&service->owners);
  _dbus_list_unlink (&service->owners, swap_link);

  _dbus_list_insert_after_link (&service->owners,
                                _dbus_list_get_first_link (&service->owners),
				swap_link);

  return TRUE;
}
Esempio n. 8
0
void
bus_expire_list_unlink (BusExpireList *list,
                        DBusList      *link)
{
  _dbus_list_unlink (&list->items, link);
}