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13 General Public License for more details.
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23 * @brief library for building GNUnet network servers
24 * @author Christian Grothoff
28 #include "gnunet_util_lib.h"
29 #include "gnunet_protocols.h"
31 #define LOG_STRERROR_FILE(kind,syscall,filename) GNUNET_log_from_strerror_file (kind, "util-server", syscall, filename)
35 * List of arrays of message handlers.
40 * This is a linked list.
42 struct HandlerList *next;
45 * NULL-terminated array of handlers.
47 const struct GNUNET_SERVER_MessageHandler *handlers;
52 * List of arrays of message handlers.
57 * This is a doubly linked list.
59 struct NotifyList *next;
62 * This is a doubly linked list.
64 struct NotifyList *prev;
69 GNUNET_SERVER_DisconnectCallback callback;
72 * Closure for callback.
79 * @brief handle for a server
81 struct GNUNET_SERVER_Handle
84 * List of handlers for incoming messages.
86 struct HandlerList *handlers;
89 * Head of list of our current clients.
91 struct GNUNET_SERVER_Client *clients_head;
94 * Head of list of our current clients.
96 struct GNUNET_SERVER_Client *clients_tail;
99 * Head of linked list of functions to call on disconnects by clients.
101 struct NotifyList *disconnect_notify_list_head;
104 * Tail of linked list of functions to call on disconnects by clients.
106 struct NotifyList *disconnect_notify_list_tail;
109 * Head of linked list of functions to call on connects by clients.
111 struct NotifyList *connect_notify_list_head;
114 * Tail of linked list of functions to call on connects by clients.
116 struct NotifyList *connect_notify_list_tail;
119 * Function to call for access control.
121 GNUNET_CONNECTION_AccessCheck access_cb;
124 * Closure for @e access_cb.
129 * NULL-terminated array of sockets used to listen for new
132 struct GNUNET_NETWORK_Handle **listen_sockets;
135 * After how long should an idle connection time
138 struct GNUNET_TIME_Relative idle_timeout;
141 * Task scheduled to do the listening.
143 struct GNUNET_SCHEDULER_Task * listen_task;
146 * Alternative function to create a MST instance.
148 GNUNET_SERVER_MstCreateCallback mst_create;
151 * Alternative function to destroy a MST instance.
153 GNUNET_SERVER_MstDestroyCallback mst_destroy;
156 * Alternative function to give data to a MST instance.
158 GNUNET_SERVER_MstReceiveCallback mst_receive;
161 * Closure for 'mst_'-callbacks.
166 * Do we ignore messages of types that we do not understand or do we
167 * require that a handler is found (and if not kill the connection)?
172 * Set to #GNUNET_YES once we are in 'soft' shutdown where we wait for
173 * all non-monitor clients to disconnect before we call
174 * #GNUNET_SERVER_destroy. See test_monitor_clients(). Set to
175 * #GNUNET_SYSERR once the final destroy task has been scheduled
176 * (we cannot run it in the same task).
178 int in_soft_shutdown;
183 * Handle server returns for aborting transmission to a client.
185 struct GNUNET_SERVER_TransmitHandle
188 * Function to call to get the message.
190 GNUNET_CONNECTION_TransmitReadyNotify callback;
193 * Closure for @e callback
198 * Active connection transmission handle.
200 struct GNUNET_CONNECTION_TransmitHandle *cth;
206 * @brief handle for a client of the server
208 struct GNUNET_SERVER_Client
212 * This is a doubly linked list.
214 struct GNUNET_SERVER_Client *next;
217 * This is a doubly linked list.
219 struct GNUNET_SERVER_Client *prev;
222 * Processing of incoming data.
227 * Server that this client belongs to.
229 struct GNUNET_SERVER_Handle *server;
232 * Client closure for callbacks.
234 struct GNUNET_CONNECTION_Handle *connection;
237 * User context value, manipulated using
238 * 'GNUNET_SERVER_client_{get/set}_user_context' functions.
243 * ID of task used to restart processing.
245 struct GNUNET_SCHEDULER_Task * restart_task;
248 * Task that warns about missing calls to #GNUNET_SERVER_receive_done.
250 struct GNUNET_SCHEDULER_Task * warn_task;
253 * Time when the warn task was started.
255 struct GNUNET_TIME_Absolute warn_start;
258 * Last activity on this socket (used to time it out
259 * if reference_count == 0).
261 struct GNUNET_TIME_Absolute last_activity;
264 * Transmission handle we return for this client from
265 * #GNUNET_SERVER_notify_transmit_ready.
267 struct GNUNET_SERVER_TransmitHandle th;
270 * After how long should an idle connection time
273 struct GNUNET_TIME_Relative idle_timeout;
276 * Number of external entities with a reference to
277 * this client object.
279 unsigned int reference_count;
282 * Was processing if incoming messages suspended while
283 * we were still processing data already received?
284 * This is a counter saying how often processing was
285 * suspended (once per handler invoked).
287 unsigned int suspended;
290 * Last size given when user context was initialized; used for
293 size_t user_context_size;
296 * Are we currently in the "process_client_buffer" function (and
297 * will hence restart the receive job on exit if suspended == 0 once
298 * we are done?). If this is set, then "receive_done" will
299 * essentially only decrement suspended; if this is not set, then
300 * "receive_done" may need to restart the receive process (either
301 * from the side-buffer or via select/recv).
303 int in_process_client_buffer;
306 * We're about to close down this client.
311 * Are we currently trying to receive? (#GNUNET_YES if we are,
312 * #GNUNET_NO if we are not, #GNUNET_SYSERR if data is already
318 * Persist the file handle for this client no matter what happens,
319 * force the OS to close once the process actually dies. Should only
320 * be used in special cases!
325 * Is this client a 'monitor' client that should not be counted
326 * when deciding on destroying the server during soft shutdown?
327 * (see also #GNUNET_SERVICE_start)
332 * Type of last message processed (for warn_no_receive_done).
340 * Return user context associated with the given client.
341 * Note: you should probably use the macro (call without the underscore).
343 * @param client client to query
344 * @param size number of bytes in user context struct (for verification only)
345 * @return pointer to user context
348 GNUNET_SERVER_client_get_user_context_ (struct GNUNET_SERVER_Client *client,
351 if ((0 == client->user_context_size) &&
352 (NULL == client->user_context))
353 return NULL; /* never set */
354 GNUNET_assert (size == client->user_context_size);
355 return client->user_context;
360 * Set user context to be associated with the given client.
361 * Note: you should probably use the macro (call without the underscore).
363 * @param client client to query
364 * @param ptr pointer to user context
365 * @param size number of bytes in user context struct (for verification only)
368 GNUNET_SERVER_client_set_user_context_ (struct GNUNET_SERVER_Client *client,
374 client->user_context_size = 0;
375 client->user_context = ptr;
378 client->user_context_size = size;
379 client->user_context = ptr;
384 * Scheduler says our listen socket is ready. Process it!
386 * @param cls handle to our server for which we are processing the listen
390 process_listen_socket (void *cls)
392 struct GNUNET_SERVER_Handle *server = cls;
393 const struct GNUNET_SCHEDULER_TaskContext *tc;
394 struct GNUNET_CONNECTION_Handle *sock;
397 server->listen_task = NULL;
398 tc = GNUNET_SCHEDULER_get_task_context ();
399 for (i = 0; NULL != server->listen_sockets[i]; i++)
401 if (GNUNET_NETWORK_fdset_isset (tc->read_ready,
402 server->listen_sockets[i]))
405 GNUNET_CONNECTION_create_from_accept (server->access_cb,
406 server->access_cb_cls,
407 server->listen_sockets[i]);
410 LOG (GNUNET_ERROR_TYPE_DEBUG,
411 "Server accepted incoming connection.\n");
412 (void) GNUNET_SERVER_connect_socket (server,
417 /* listen for more! */
418 GNUNET_SERVER_resume (server);
423 * Create and initialize a listen socket for the server.
425 * @param server_addr address to listen on
426 * @param socklen length of @a server_addr
427 * @return NULL on error, otherwise the listen socket
429 static struct GNUNET_NETWORK_Handle *
430 open_listen_socket (const struct sockaddr *server_addr,
433 struct GNUNET_NETWORK_Handle *sock;
437 switch (server_addr->sa_family)
440 port = ntohs (((const struct sockaddr_in *) server_addr)->sin_port);
443 port = ntohs (((const struct sockaddr_in6 *) server_addr)->sin6_port);
453 sock = GNUNET_NETWORK_socket_create (server_addr->sa_family, SOCK_STREAM, 0);
456 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "socket");
460 /* bind the socket */
461 if (GNUNET_OK != GNUNET_NETWORK_socket_bind (sock, server_addr, socklen))
464 if (EADDRINUSE != errno)
466 /* we don't log 'EADDRINUSE' here since an IPv4 bind may
467 * fail if we already took the port on IPv6; if both IPv4 and
468 * IPv6 binds fail, then our caller will log using the
469 * errno preserved in 'eno' */
470 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR,
473 LOG (GNUNET_ERROR_TYPE_ERROR,
474 _("`%s' failed for port %d (%s).\n"),
477 (AF_INET == server_addr->sa_family) ? "IPv4" : "IPv6");
483 LOG (GNUNET_ERROR_TYPE_WARNING,
484 _("`%s' failed for port %d (%s): address already in use\n"),
486 (AF_INET == server_addr->sa_family) ? "IPv4" : "IPv6");
487 else if (AF_UNIX == server_addr->sa_family)
489 LOG (GNUNET_ERROR_TYPE_WARNING,
490 _("`%s' failed for `%s': address already in use\n"),
492 GNUNET_a2s (server_addr, socklen));
495 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (sock));
499 if (GNUNET_OK != GNUNET_NETWORK_socket_listen (sock, 5))
501 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR,
503 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (sock));
508 LOG (GNUNET_ERROR_TYPE_DEBUG,
509 "Server starts to listen on port %u.\n",
516 * Create a new server.
518 * @param access_cb function for access control
519 * @param access_cb_cls closure for @a access_cb
520 * @param lsocks NULL-terminated array of listen sockets
521 * @param idle_timeout after how long should we timeout idle connections?
522 * @param require_found if #GNUNET_YES, connections sending messages of unknown type
524 * @return handle for the new server, NULL on error
525 * (typically, "port" already in use)
527 struct GNUNET_SERVER_Handle *
528 GNUNET_SERVER_create_with_sockets (GNUNET_CONNECTION_AccessCheck access_cb,
530 struct GNUNET_NETWORK_Handle **lsocks,
531 struct GNUNET_TIME_Relative idle_timeout,
534 struct GNUNET_SERVER_Handle *server;
536 server = GNUNET_new (struct GNUNET_SERVER_Handle);
537 server->idle_timeout = idle_timeout;
538 server->listen_sockets = lsocks;
539 server->access_cb = access_cb;
540 server->access_cb_cls = access_cb_cls;
541 server->require_found = require_found;
543 GNUNET_SERVER_resume (server);
549 * Create a new server.
551 * @param access_cb function for access control
552 * @param access_cb_cls closure for @a access_cb
553 * @param server_addr address to listen on (including port), NULL terminated array
554 * @param socklen length of server_addr
555 * @param idle_timeout after how long should we timeout idle connections?
556 * @param require_found if YES, connections sending messages of unknown type
558 * @return handle for the new server, NULL on error
559 * (typically, "port" already in use)
561 struct GNUNET_SERVER_Handle *
562 GNUNET_SERVER_create (GNUNET_CONNECTION_AccessCheck access_cb,
564 struct sockaddr *const *server_addr,
565 const socklen_t * socklen,
566 struct GNUNET_TIME_Relative idle_timeout,
569 struct GNUNET_NETWORK_Handle **lsocks;
576 while (NULL != server_addr[i])
580 lsocks = GNUNET_malloc (sizeof (struct GNUNET_NETWORK_Handle *) * (i + 1));
583 while (NULL != server_addr[i])
587 if ( (socklen[k] == socklen[i]) &&
588 (0 == memcmp (server_addr[k], server_addr[i], socklen[i])) )
595 /* duplicate address, skip */
599 lsocks[j] = open_listen_socket (server_addr[i], socklen[i]);
600 if (NULL != lsocks[j])
607 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "bind");
608 GNUNET_free (lsocks);
616 return GNUNET_SERVER_create_with_sockets (access_cb,
625 * Set the 'monitor' flag on this client. Clients which have been
626 * marked as 'monitors' won't prevent the server from shutting down
627 * once '#GNUNET_SERVER_stop_listening()' has been invoked. The idea is
628 * that for "normal" clients we likely want to allow them to process
629 * their requests; however, monitor-clients are likely to 'never'
630 * disconnect during shutdown and thus will not be considered when
631 * determining if the server should continue to exist after
632 * #GNUNET_SERVER_destroy() has been called.
634 * @param client the client to set the 'monitor' flag on
637 GNUNET_SERVER_client_mark_monitor (struct GNUNET_SERVER_Client *client)
639 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
640 "Marking client as monitor!\n");
641 client->is_monitor = GNUNET_YES;
646 * Helper function for #test_monitor_clients() to trigger
647 * #GNUNET_SERVER_destroy() after the stack has unwound.
649 * @param cls the `struct GNUNET_SERVER_Handle *` to destroy
652 do_destroy (void *cls)
654 struct GNUNET_SERVER_Handle *server = cls;
656 GNUNET_SERVER_destroy (server);
661 * Check if only 'monitor' clients are left. If so, destroy the
664 * @param server server to test for full shutdown
667 test_monitor_clients (struct GNUNET_SERVER_Handle *server)
669 struct GNUNET_SERVER_Client *client;
671 if (GNUNET_YES != server->in_soft_shutdown)
673 for (client = server->clients_head; NULL != client; client = client->next)
674 if (GNUNET_NO == client->is_monitor)
675 return; /* not done yet */
676 server->in_soft_shutdown = GNUNET_SYSERR;
677 (void) GNUNET_SCHEDULER_add_now (&do_destroy, server);
682 * Suspend accepting connections from the listen socket temporarily.
684 * @param server server to stop accepting connections.
687 GNUNET_SERVER_suspend (struct GNUNET_SERVER_Handle *server)
689 if (NULL != server->listen_task)
691 GNUNET_SCHEDULER_cancel (server->listen_task);
692 server->listen_task = NULL;
698 * Resume accepting connections from the listen socket.
700 * @param server server to stop accepting connections.
703 GNUNET_SERVER_resume (struct GNUNET_SERVER_Handle *server)
705 struct GNUNET_NETWORK_FDSet *r;
708 if (NULL == server->listen_sockets)
710 if (NULL == server->listen_sockets[0])
711 return; /* nothing to do, no listen sockets! */
712 if (NULL == server->listen_sockets[1])
714 /* simplified method: no fd set needed; this is then much simpler
715 and much more efficient */
716 server->listen_task =
717 GNUNET_SCHEDULER_add_read_net_with_priority (GNUNET_TIME_UNIT_FOREVER_REL,
718 GNUNET_SCHEDULER_PRIORITY_HIGH,
719 server->listen_sockets[0],
720 &process_listen_socket, server);
723 r = GNUNET_NETWORK_fdset_create ();
725 while (NULL != server->listen_sockets[i])
726 GNUNET_NETWORK_fdset_set (r, server->listen_sockets[i++]);
727 server->listen_task =
728 GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_HIGH,
729 GNUNET_TIME_UNIT_FOREVER_REL, r, NULL,
730 &process_listen_socket, server);
731 GNUNET_NETWORK_fdset_destroy (r);
736 * Stop the listen socket and get ready to shutdown the server
737 * once only 'monitor' clients are left.
739 * @param server server to stop listening on
742 GNUNET_SERVER_stop_listening (struct GNUNET_SERVER_Handle *server)
746 LOG (GNUNET_ERROR_TYPE_DEBUG,
747 "Server in soft shutdown\n");
748 if (NULL != server->listen_task)
750 GNUNET_SCHEDULER_cancel (server->listen_task);
751 server->listen_task = NULL;
753 if (NULL != server->listen_sockets)
756 while (NULL != server->listen_sockets[i])
757 GNUNET_break (GNUNET_OK ==
758 GNUNET_NETWORK_socket_close (server->listen_sockets[i++]));
759 GNUNET_free (server->listen_sockets);
760 server->listen_sockets = NULL;
762 if (GNUNET_NO == server->in_soft_shutdown)
763 server->in_soft_shutdown = GNUNET_YES;
764 test_monitor_clients (server);
769 * Free resources held by this server.
771 * @param server server to destroy
774 GNUNET_SERVER_destroy (struct GNUNET_SERVER_Handle *server)
776 struct HandlerList *hpos;
777 struct NotifyList *npos;
780 LOG (GNUNET_ERROR_TYPE_DEBUG,
781 "Server shutting down.\n");
782 if (NULL != server->listen_task)
784 GNUNET_SCHEDULER_cancel (server->listen_task);
785 server->listen_task = NULL;
787 if (NULL != server->listen_sockets)
790 while (NULL != server->listen_sockets[i])
791 GNUNET_break (GNUNET_OK ==
792 GNUNET_NETWORK_socket_close (server->listen_sockets[i++]));
793 GNUNET_free (server->listen_sockets);
794 server->listen_sockets = NULL;
796 while (NULL != server->clients_head)
797 GNUNET_SERVER_client_disconnect (server->clients_head);
798 while (NULL != (hpos = server->handlers))
800 server->handlers = hpos->next;
803 while (NULL != (npos = server->disconnect_notify_list_head))
805 npos->callback (npos->callback_cls,
807 GNUNET_CONTAINER_DLL_remove (server->disconnect_notify_list_head,
808 server->disconnect_notify_list_tail,
812 while (NULL != (npos = server->connect_notify_list_head))
814 npos->callback (npos->callback_cls,
816 GNUNET_CONTAINER_DLL_remove (server->connect_notify_list_head,
817 server->connect_notify_list_tail,
821 GNUNET_free (server);
826 * Add additional handlers to an existing server.
828 * @param server the server to add handlers to
829 * @param handlers array of message handlers for
830 * incoming messages; the last entry must
831 * have "NULL" for the "callback"; multiple
832 * entries for the same type are allowed,
833 * they will be called in order of occurence.
834 * These handlers can be removed later;
835 * the handlers array must exist until removed
836 * (or server is destroyed).
839 GNUNET_SERVER_add_handlers (struct GNUNET_SERVER_Handle *server,
840 const struct GNUNET_SERVER_MessageHandler *handlers)
842 struct HandlerList *p;
844 p = GNUNET_new (struct HandlerList);
845 p->handlers = handlers;
846 p->next = server->handlers;
847 server->handlers = p;
852 * Change functions used by the server to tokenize the message stream.
853 * (very rarely used).
855 * @param server server to modify
856 * @param create new tokenizer initialization function
857 * @param destroy new tokenizer destruction function
858 * @param receive new tokenizer receive function
859 * @param cls closure for @a create, @a receive, @a destroy
862 GNUNET_SERVER_set_callbacks (struct GNUNET_SERVER_Handle *server,
863 GNUNET_SERVER_MstCreateCallback create,
864 GNUNET_SERVER_MstDestroyCallback destroy,
865 GNUNET_SERVER_MstReceiveCallback receive,
868 server->mst_create = create;
869 server->mst_destroy = destroy;
870 server->mst_receive = receive;
871 server->mst_cls = cls;
876 * Task run to warn about missing calls to #GNUNET_SERVER_receive_done.
878 * @param cls our `struct GNUNET_SERVER_Client *` to process more requests from
881 warn_no_receive_done (void *cls)
883 struct GNUNET_SERVER_Client *client = cls;
885 GNUNET_break (0 != client->warn_type); /* type should never be 0 here, as we don't use 0 */
887 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES,
888 &warn_no_receive_done, client);
889 LOG (GNUNET_ERROR_TYPE_WARNING,
890 _("Processing code for message of type %u did not call `GNUNET_SERVER_receive_done' after %s\n"),
891 (unsigned int) client->warn_type,
892 GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_duration (client->warn_start),
898 * Disable the warning the server issues if a message is not acknowledged
899 * in a timely fashion. Use this call if a client is intentionally delayed
900 * for a while. Only applies to the current message.
902 * @param client client for which to disable the warning
905 GNUNET_SERVER_disable_receive_done_warning (struct GNUNET_SERVER_Client *client)
907 if (NULL != client->warn_task)
909 GNUNET_SCHEDULER_cancel (client->warn_task);
910 client->warn_task = NULL;
916 * Inject a message into the server, pretend it came
917 * from the specified client. Delivery of the message
918 * will happen instantly (if a handler is installed;
919 * otherwise the call does nothing).
921 * @param server the server receiving the message
922 * @param sender the "pretended" sender of the message
924 * @param message message to transmit
925 * @return #GNUNET_OK if the message was OK and the
926 * connection can stay open
927 * #GNUNET_SYSERR if the connection to the
928 * client should be shut down
931 GNUNET_SERVER_inject (struct GNUNET_SERVER_Handle *server,
932 struct GNUNET_SERVER_Client *sender,
933 const struct GNUNET_MessageHeader *message)
935 struct HandlerList *pos;
936 const struct GNUNET_SERVER_MessageHandler *mh;
942 type = ntohs (message->type);
943 size = ntohs (message->size);
944 LOG (GNUNET_ERROR_TYPE_INFO,
945 "Received message of type %u and size %u from client\n",
948 for (pos = server->handlers; NULL != pos; pos = pos->next)
951 while (pos->handlers[i].callback != NULL)
953 mh = &pos->handlers[i];
954 if ((mh->type == type) || (mh->type == GNUNET_MESSAGE_TYPE_ALL))
956 if ((0 != mh->expected_size) && (mh->expected_size != size))
958 #if GNUNET8_NETWORK_IS_DEAD
959 LOG (GNUNET_ERROR_TYPE_WARNING,
960 "Expected %u bytes for message of type %u, got %u\n",
961 mh->expected_size, mh->type, size);
964 LOG (GNUNET_ERROR_TYPE_DEBUG,
965 "Expected %u bytes for message of type %u, got %u\n",
966 mh->expected_size, mh->type, size);
968 return GNUNET_SYSERR;
972 if ( (0 == sender->suspended) &&
973 (NULL == sender->warn_task) )
975 GNUNET_break (0 != type); /* type should never be 0 here, as we don't use 0 */
976 sender->warn_start = GNUNET_TIME_absolute_get ();
978 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES,
979 &warn_no_receive_done,
981 sender->warn_type = type;
985 mh->callback (mh->callback_cls, sender, message);
991 if (GNUNET_NO == found)
993 LOG (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
994 "Received message of unknown type %d\n", type);
995 if (GNUNET_YES == server->require_found)
996 return GNUNET_SYSERR;
1003 * We are receiving an incoming message. Process it.
1005 * @param cls our closure (handle for the client)
1006 * @param buf buffer with data received from network
1007 * @param available number of bytes available in buf
1008 * @param addr address of the sender
1009 * @param addrlen length of @a addr
1010 * @param errCode code indicating errors receiving, 0 for success
1013 process_incoming (void *cls,
1016 const struct sockaddr *addr,
1022 * Process messages from the client's message tokenizer until either
1023 * the tokenizer is empty (and then schedule receiving more), or
1024 * until some handler is not immediately done (then wait for restart_processing)
1027 * @param client the client to process, RC must have already been increased
1028 * using #GNUNET_SERVER_client_keep and will be decreased by one in this
1030 * @param ret #GNUNET_NO to start processing from the buffer,
1031 * #GNUNET_OK if the mst buffer is drained and we should instantly go back to receiving
1032 * #GNUNET_SYSERR if we should instantly abort due to error in a previous step
1035 process_mst (struct GNUNET_SERVER_Client *client,
1038 while ((GNUNET_SYSERR != ret) && (NULL != client->server) &&
1039 (GNUNET_YES != client->shutdown_now) && (0 == client->suspended))
1041 if (GNUNET_OK == ret)
1043 LOG (GNUNET_ERROR_TYPE_DEBUG,
1044 "Server re-enters receive loop, timeout: %s.\n",
1045 GNUNET_STRINGS_relative_time_to_string (client->idle_timeout, GNUNET_YES));
1046 client->receive_pending = GNUNET_YES;
1047 GNUNET_CONNECTION_receive (client->connection,
1048 GNUNET_SERVER_MAX_MESSAGE_SIZE - 1,
1049 client->idle_timeout,
1054 LOG (GNUNET_ERROR_TYPE_DEBUG,
1055 "Server processes additional messages instantly.\n");
1056 if (NULL != client->server->mst_receive)
1058 client->server->mst_receive (client->server->mst_cls, client->mst,
1059 client, NULL, 0, GNUNET_NO, GNUNET_YES);
1062 GNUNET_SERVER_mst_receive (client->mst, client, NULL, 0, GNUNET_NO,
1065 LOG (GNUNET_ERROR_TYPE_DEBUG,
1066 "Server leaves instant processing loop: ret = %d, server = %p, shutdown = %d, suspended = %u\n",
1067 ret, client->server,
1068 client->shutdown_now,
1070 if (GNUNET_NO == ret)
1072 LOG (GNUNET_ERROR_TYPE_DEBUG,
1073 "Server has more data pending but is suspended.\n");
1074 client->receive_pending = GNUNET_SYSERR; /* data pending */
1076 if ( (GNUNET_SYSERR == ret) ||
1077 (GNUNET_YES == client->shutdown_now) )
1078 GNUNET_SERVER_client_disconnect (client);
1083 * We are receiving an incoming message. Process it.
1085 * @param cls our closure (handle for the client)
1086 * @param buf buffer with data received from network
1087 * @param available number of bytes available in buf
1088 * @param addr address of the sender
1089 * @param addrlen length of @a addr
1090 * @param errCode code indicating errors receiving, 0 for success
1093 process_incoming (void *cls,
1096 const struct sockaddr *addr,
1100 struct GNUNET_SERVER_Client *client = cls;
1101 struct GNUNET_SERVER_Handle *server = client->server;
1102 struct GNUNET_TIME_Absolute end;
1103 struct GNUNET_TIME_Absolute now;
1106 GNUNET_assert (GNUNET_YES == client->receive_pending);
1107 client->receive_pending = GNUNET_NO;
1108 now = GNUNET_TIME_absolute_get ();
1109 end = GNUNET_TIME_absolute_add (client->last_activity,
1110 client->idle_timeout);
1112 if ( (NULL == buf) &&
1116 (GNUNET_YES != client->shutdown_now) &&
1118 (GNUNET_YES == GNUNET_CONNECTION_check (client->connection)) &&
1119 (end.abs_value_us > now.abs_value_us) )
1121 /* wait longer, timeout changed (i.e. due to us sending) */
1122 LOG (GNUNET_ERROR_TYPE_DEBUG,
1123 "Receive time out, but no disconnect due to sending (%p)\n",
1125 client->receive_pending = GNUNET_YES;
1126 GNUNET_CONNECTION_receive (client->connection,
1127 GNUNET_SERVER_MAX_MESSAGE_SIZE - 1,
1128 GNUNET_TIME_absolute_get_remaining (end),
1133 if ( (NULL == buf) ||
1137 (GNUNET_YES == client->shutdown_now) ||
1138 (GNUNET_YES != GNUNET_CONNECTION_check (client->connection)) )
1140 /* other side closed connection, error connecting, etc. */
1141 LOG (GNUNET_ERROR_TYPE_DEBUG,
1142 "Failed to connect or other side closed connection (%p)\n",
1144 GNUNET_SERVER_client_disconnect (client);
1147 LOG (GNUNET_ERROR_TYPE_DEBUG,
1148 "Server receives %u bytes from `%s'.\n",
1149 (unsigned int) available,
1150 GNUNET_a2s (addr, addrlen));
1151 GNUNET_SERVER_client_keep (client);
1152 client->last_activity = now;
1154 if (NULL != server->mst_receive)
1156 ret = client->server->mst_receive (client->server->mst_cls,
1164 else if (NULL != client->mst)
1167 GNUNET_SERVER_mst_receive (client->mst,
1179 process_mst (client,
1181 GNUNET_SERVER_client_drop (client);
1186 * Task run to start again receiving from the network
1187 * and process requests.
1189 * @param cls our `struct GNUNET_SERVER_Client *` to process more requests from
1192 restart_processing (void *cls)
1194 struct GNUNET_SERVER_Client *client = cls;
1196 GNUNET_assert (GNUNET_YES != client->shutdown_now);
1197 client->restart_task = NULL;
1198 if (GNUNET_NO == client->receive_pending)
1200 LOG (GNUNET_ERROR_TYPE_DEBUG, "Server begins to read again from client.\n");
1201 client->receive_pending = GNUNET_YES;
1202 GNUNET_CONNECTION_receive (client->connection,
1203 GNUNET_SERVER_MAX_MESSAGE_SIZE - 1,
1204 client->idle_timeout,
1209 LOG (GNUNET_ERROR_TYPE_DEBUG,
1210 "Server continues processing messages still in the buffer.\n");
1211 GNUNET_SERVER_client_keep (client);
1212 client->receive_pending = GNUNET_NO;
1213 process_mst (client,
1215 GNUNET_SERVER_client_drop (client);
1220 * This function is called whenever our inbound message tokenizer has
1221 * received a complete message.
1223 * @param cls closure (struct GNUNET_SERVER_Handle)
1224 * @param client identification of the client (`struct GNUNET_SERVER_Client *`)
1225 * @param message the actual message
1227 * @return #GNUNET_OK on success, #GNUNET_SYSERR to stop further processing
1230 client_message_tokenizer_callback (void *cls,
1232 const struct GNUNET_MessageHeader *message)
1234 struct GNUNET_SERVER_Handle *server = cls;
1235 struct GNUNET_SERVER_Client *sender = client;
1238 LOG (GNUNET_ERROR_TYPE_DEBUG,
1239 "Tokenizer gives server message of type %u and size %u from client\n",
1240 ntohs (message->type), ntohs (message->size));
1241 sender->in_process_client_buffer = GNUNET_YES;
1242 ret = GNUNET_SERVER_inject (server, sender, message);
1243 sender->in_process_client_buffer = GNUNET_NO;
1244 if ( (GNUNET_OK != ret) || (GNUNET_YES == sender->shutdown_now) )
1246 GNUNET_SERVER_client_disconnect (sender);
1247 return GNUNET_SYSERR;
1254 * Add a TCP socket-based connection to the set of handles managed by
1255 * this server. Use this function for outgoing (P2P) connections that
1256 * we initiated (and where this server should process incoming
1259 * @param server the server to use
1260 * @param connection the connection to manage (client must
1261 * stop using this connection from now on)
1262 * @return the client handle
1264 struct GNUNET_SERVER_Client *
1265 GNUNET_SERVER_connect_socket (struct GNUNET_SERVER_Handle *server,
1266 struct GNUNET_CONNECTION_Handle *connection)
1268 struct GNUNET_SERVER_Client *client;
1269 struct NotifyList *n;
1271 client = GNUNET_new (struct GNUNET_SERVER_Client);
1272 client->connection = connection;
1273 client->server = server;
1274 client->last_activity = GNUNET_TIME_absolute_get ();
1275 client->idle_timeout = server->idle_timeout;
1276 GNUNET_CONTAINER_DLL_insert (server->clients_head,
1277 server->clients_tail,
1279 if (NULL != server->mst_create)
1281 server->mst_create (server->mst_cls, client);
1284 GNUNET_SERVER_mst_create (&client_message_tokenizer_callback,
1286 GNUNET_assert (NULL != client->mst);
1287 for (n = server->connect_notify_list_head; NULL != n; n = n->next)
1288 n->callback (n->callback_cls, client);
1289 client->receive_pending = GNUNET_YES;
1290 GNUNET_CONNECTION_receive (client->connection,
1291 GNUNET_SERVER_MAX_MESSAGE_SIZE - 1,
1292 client->idle_timeout,
1300 * Change the timeout for a particular client. Decreasing the timeout
1301 * may not go into effect immediately (only after the previous timeout
1302 * times out or activity happens on the socket).
1304 * @param client the client to update
1305 * @param timeout new timeout for activities on the socket
1308 GNUNET_SERVER_client_set_timeout (struct GNUNET_SERVER_Client *client,
1309 struct GNUNET_TIME_Relative timeout)
1311 client->idle_timeout = timeout;
1316 * Notify the server that the given client handle should
1317 * be kept (keeps the connection up if possible, increments
1318 * the internal reference counter).
1320 * @param client the client to keep
1323 GNUNET_SERVER_client_keep (struct GNUNET_SERVER_Client *client)
1325 client->reference_count++;
1330 * Notify the server that the given client handle is no
1331 * longer required. Decrements the reference counter. If
1332 * that counter reaches zero an inactive connection maybe
1335 * @param client the client to drop
1338 GNUNET_SERVER_client_drop (struct GNUNET_SERVER_Client *client)
1340 GNUNET_assert (client->reference_count > 0);
1341 client->reference_count--;
1342 if ((GNUNET_YES == client->shutdown_now) && (0 == client->reference_count))
1343 GNUNET_SERVER_client_disconnect (client);
1348 * Obtain the network address of the other party.
1350 * @param client the client to get the address for
1351 * @param addr where to store the address
1352 * @param addrlen where to store the length of the @a addr
1353 * @return #GNUNET_OK on success
1356 GNUNET_SERVER_client_get_address (struct GNUNET_SERVER_Client *client,
1357 void **addr, size_t * addrlen)
1359 return GNUNET_CONNECTION_get_address (client->connection, addr, addrlen);
1364 * Ask the server to notify us whenever a client disconnects.
1365 * This function is called whenever the actual network connection
1366 * is closed; the reference count may be zero or larger than zero
1369 * @param server the server manageing the clients
1370 * @param callback function to call on disconnect
1371 * @param callback_cls closure for @a callback
1374 GNUNET_SERVER_disconnect_notify (struct GNUNET_SERVER_Handle *server,
1375 GNUNET_SERVER_DisconnectCallback callback,
1378 struct NotifyList *n;
1380 n = GNUNET_new (struct NotifyList);
1381 n->callback = callback;
1382 n->callback_cls = callback_cls;
1383 GNUNET_CONTAINER_DLL_insert (server->disconnect_notify_list_head,
1384 server->disconnect_notify_list_tail,
1390 * Ask the server to notify us whenever a client connects.
1391 * This function is called whenever the actual network connection
1392 * is opened. If the server is destroyed before this
1393 * notification is explicitly cancelled, the 'callback' will
1394 * once be called with a 'client' argument of NULL to indicate
1395 * that the server itself is now gone (and that the callback
1396 * won't be called anymore and also can no longer be cancelled).
1398 * @param server the server manageing the clients
1399 * @param callback function to call on sconnect
1400 * @param callback_cls closure for @a callback
1403 GNUNET_SERVER_connect_notify (struct GNUNET_SERVER_Handle *server,
1404 GNUNET_SERVER_ConnectCallback callback,
1407 struct NotifyList *n;
1408 struct GNUNET_SERVER_Client *client;
1410 n = GNUNET_new (struct NotifyList);
1411 n->callback = callback;
1412 n->callback_cls = callback_cls;
1413 GNUNET_CONTAINER_DLL_insert (server->connect_notify_list_head,
1414 server->connect_notify_list_tail,
1416 for (client = server->clients_head; NULL != client; client = client->next)
1417 callback (callback_cls, client);
1422 * Ask the server to stop notifying us whenever a client connects.
1424 * @param server the server manageing the clients
1425 * @param callback function to call on connect
1426 * @param callback_cls closure for @a callback
1429 GNUNET_SERVER_disconnect_notify_cancel (struct GNUNET_SERVER_Handle *server,
1430 GNUNET_SERVER_DisconnectCallback callback,
1433 struct NotifyList *pos;
1435 for (pos = server->disconnect_notify_list_head; NULL != pos; pos = pos->next)
1436 if ((pos->callback == callback) && (pos->callback_cls == callback_cls))
1443 GNUNET_CONTAINER_DLL_remove (server->disconnect_notify_list_head,
1444 server->disconnect_notify_list_tail,
1451 * Ask the server to stop notifying us whenever a client disconnects.
1453 * @param server the server manageing the clients
1454 * @param callback function to call on disconnect
1455 * @param callback_cls closure for @a callback
1458 GNUNET_SERVER_connect_notify_cancel (struct GNUNET_SERVER_Handle *server,
1459 GNUNET_SERVER_ConnectCallback callback,
1462 struct NotifyList *pos;
1464 for (pos = server->connect_notify_list_head; NULL != pos; pos = pos->next)
1465 if ((pos->callback == callback) && (pos->callback_cls == callback_cls))
1472 GNUNET_CONTAINER_DLL_remove (server->connect_notify_list_head,
1473 server->connect_notify_list_tail,
1480 * Destroy the connection that is passed in via @a cls. Used
1481 * as calling #GNUNET_CONNECTION_destroy from within a function
1482 * that was itself called from within process_notify() of
1483 * 'connection.c' is not allowed (see #2329).
1485 * @param cls connection to destroy
1488 destroy_connection (void *cls)
1490 struct GNUNET_CONNECTION_Handle *connection = cls;
1492 GNUNET_CONNECTION_destroy (connection);
1497 * Ask the server to disconnect from the given client.
1498 * This is the same as returning #GNUNET_SYSERR from a message
1499 * handler, except that it allows dropping of a client even
1500 * when not handling a message from that client.
1502 * @param client the client to disconnect from
1505 GNUNET_SERVER_client_disconnect (struct GNUNET_SERVER_Client *client)
1507 struct GNUNET_SERVER_Handle *server = client->server;
1508 struct NotifyList *n;
1510 LOG (GNUNET_ERROR_TYPE_DEBUG,
1511 "Client is being disconnected from the server.\n");
1512 if (NULL != client->restart_task)
1514 GNUNET_SCHEDULER_cancel (client->restart_task);
1515 client->restart_task = NULL;
1517 if (NULL != client->warn_task)
1519 GNUNET_SCHEDULER_cancel (client->warn_task);
1520 client->warn_task = NULL;
1522 if (GNUNET_YES == client->receive_pending)
1524 GNUNET_CONNECTION_receive_cancel (client->connection);
1525 client->receive_pending = GNUNET_NO;
1527 client->shutdown_now = GNUNET_YES;
1528 client->reference_count++; /* make sure nobody else clean up client... */
1529 if ( (NULL != client->mst) &&
1532 GNUNET_CONTAINER_DLL_remove (server->clients_head,
1533 server->clients_tail,
1535 if (NULL != server->mst_destroy)
1536 server->mst_destroy (server->mst_cls,
1539 GNUNET_SERVER_mst_destroy (client->mst);
1541 for (n = server->disconnect_notify_list_head; NULL != n; n = n->next)
1542 n->callback (n->callback_cls,
1545 client->reference_count--;
1546 if (client->reference_count > 0)
1548 LOG (GNUNET_ERROR_TYPE_DEBUG,
1549 "RC of %p still positive, not destroying everything.\n",
1551 client->server = NULL;
1554 if (GNUNET_YES == client->in_process_client_buffer)
1556 LOG (GNUNET_ERROR_TYPE_DEBUG,
1557 "Still processing inputs of %p, not destroying everything.\n",
1561 LOG (GNUNET_ERROR_TYPE_DEBUG,
1562 "RC of %p now zero, destroying everything.\n",
1564 if (GNUNET_YES == client->persist)
1565 GNUNET_CONNECTION_persist_ (client->connection);
1566 if (NULL != client->th.cth)
1567 GNUNET_SERVER_notify_transmit_ready_cancel (&client->th);
1568 (void) GNUNET_SCHEDULER_add_now (&destroy_connection,
1569 client->connection);
1570 /* need to cancel again, as it might have been re-added
1571 in the meantime (i.e. during callbacks) */
1572 if (NULL != client->warn_task)
1574 GNUNET_SCHEDULER_cancel (client->warn_task);
1575 client->warn_task = NULL;
1577 if (GNUNET_YES == client->receive_pending)
1579 GNUNET_CONNECTION_receive_cancel (client->connection);
1580 client->receive_pending = GNUNET_NO;
1582 GNUNET_free (client);
1583 /* we might be in soft-shutdown, test if we're done */
1585 test_monitor_clients (server);
1590 * Disable the "CORK" feature for communication with the given client,
1591 * forcing the OS to immediately flush the buffer on transmission
1592 * instead of potentially buffering multiple messages.
1594 * @param client handle to the client
1595 * @return #GNUNET_OK on success
1598 GNUNET_SERVER_client_disable_corking (struct GNUNET_SERVER_Client *client)
1600 return GNUNET_CONNECTION_disable_corking (client->connection);
1605 * Wrapper for transmission notification that calls the original
1606 * callback and update the last activity time for our connection.
1608 * @param cls the `struct GNUNET_SERVER_Client *`
1609 * @param size number of bytes we can transmit
1610 * @param buf where to copy the message
1611 * @return number of bytes actually transmitted
1614 transmit_ready_callback_wrapper (void *cls, size_t size, void *buf)
1616 struct GNUNET_SERVER_Client *client = cls;
1617 GNUNET_CONNECTION_TransmitReadyNotify callback;
1619 client->th.cth = NULL;
1620 callback = client->th.callback;
1621 client->th.callback = NULL;
1622 client->last_activity = GNUNET_TIME_absolute_get ();
1623 return callback (client->th.callback_cls, size, buf);
1628 * Notify us when the server has enough space to transmit
1629 * a message of the given size to the given client.
1631 * @param client client to transmit message to
1632 * @param size requested amount of buffer space
1633 * @param timeout after how long should we give up (and call
1634 * notify with buf NULL and size 0)?
1635 * @param callback function to call when space is available
1636 * @param callback_cls closure for @a callback
1637 * @return non-NULL if the notify callback was queued; can be used
1638 * to cancel the request using
1639 * #GNUNET_SERVER_notify_transmit_ready_cancel().
1640 * NULL if we are already going to notify someone else (busy)
1642 struct GNUNET_SERVER_TransmitHandle *
1643 GNUNET_SERVER_notify_transmit_ready (struct GNUNET_SERVER_Client *client,
1645 struct GNUNET_TIME_Relative timeout,
1646 GNUNET_CONNECTION_TransmitReadyNotify callback,
1649 if (NULL != client->th.callback)
1651 client->th.callback_cls = callback_cls;
1652 client->th.callback = callback;
1653 client->th.cth = GNUNET_CONNECTION_notify_transmit_ready (client->connection, size,
1655 &transmit_ready_callback_wrapper,
1662 * Abort transmission request.
1664 * @param th request to abort
1667 GNUNET_SERVER_notify_transmit_ready_cancel (struct GNUNET_SERVER_TransmitHandle *th)
1669 GNUNET_CONNECTION_notify_transmit_ready_cancel (th->cth);
1671 th->callback = NULL;
1676 * Set the persistent flag on this client, used to setup client connection
1677 * to only be killed when the service it's connected to is actually dead.
1679 * @param client the client to set the persistent flag on
1682 GNUNET_SERVER_client_persist_ (struct GNUNET_SERVER_Client *client)
1684 client->persist = GNUNET_YES;
1689 * Resume receiving from this client, we are done processing the
1690 * current request. This function must be called from within each
1691 * GNUNET_SERVER_MessageCallback (or its respective continuations).
1693 * @param client client we were processing a message of
1694 * @param success #GNUNET_OK to keep the connection open and
1695 * continue to receive
1696 * #GNUNET_NO to close the connection (normal behavior)
1697 * #GNUNET_SYSERR to close the connection (signal
1701 GNUNET_SERVER_receive_done (struct GNUNET_SERVER_Client *client,
1706 GNUNET_assert (client->suspended > 0);
1707 client->suspended--;
1708 if (GNUNET_OK != success)
1710 LOG (GNUNET_ERROR_TYPE_DEBUG,
1711 "GNUNET_SERVER_receive_done called with failure indication\n");
1712 if ( (client->reference_count > 0) || (client->suspended > 0) )
1713 client->shutdown_now = GNUNET_YES;
1715 GNUNET_SERVER_client_disconnect (client);
1718 if (client->suspended > 0)
1720 LOG (GNUNET_ERROR_TYPE_DEBUG,
1721 "GNUNET_SERVER_receive_done called, but more clients pending\n");
1724 if (NULL != client->warn_task)
1726 GNUNET_SCHEDULER_cancel (client->warn_task);
1727 client->warn_task = NULL;
1729 if (GNUNET_YES == client->in_process_client_buffer)
1731 LOG (GNUNET_ERROR_TYPE_DEBUG,
1732 "GNUNET_SERVER_receive_done called while still in processing loop\n");
1735 if ((NULL == client->server) || (GNUNET_YES == client->shutdown_now))
1737 GNUNET_SERVER_client_disconnect (client);
1740 LOG (GNUNET_ERROR_TYPE_DEBUG,
1741 "GNUNET_SERVER_receive_done causes restart in reading from the socket\n");
1742 GNUNET_assert (NULL == client->restart_task);
1743 client->restart_task = GNUNET_SCHEDULER_add_now (&restart_processing,
1748 /* end of server.c */