2 This file is part of GNUnet.
3 Copyright (C) 2009-2013 GNUnet e.V.
5 GNUnet is free software: you can redistribute it and/or modify it
6 under the terms of the GNU Affero General Public License as published
7 by the Free Software Foundation, either version 3 of the License,
8 or (at your option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Affero General Public License for more details.
15 You should have received a copy of the GNU Affero General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
18 SPDX-License-Identifier: AGPL3.0-or-later
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, \
32 filename) GNUNET_log_from_strerror_file (kind, \
39 * List of arrays of message handlers.
44 * This is a linked list.
46 struct HandlerList *next;
49 * NULL-terminated array of handlers.
51 const struct GNUNET_SERVER_MessageHandler *handlers;
56 * List of arrays of message handlers.
61 * This is a doubly linked list.
63 struct NotifyList *next;
66 * This is a doubly linked list.
68 struct NotifyList *prev;
73 GNUNET_SERVER_DisconnectCallback callback;
76 * Closure for callback.
83 * @brief handle for a server
85 struct GNUNET_SERVER_Handle
88 * List of handlers for incoming messages.
90 struct HandlerList *handlers;
93 * Head of list of our current clients.
95 struct GNUNET_SERVER_Client *clients_head;
98 * Head of list of our current clients.
100 struct GNUNET_SERVER_Client *clients_tail;
103 * Head of linked list of functions to call on disconnects by clients.
105 struct NotifyList *disconnect_notify_list_head;
108 * Tail of linked list of functions to call on disconnects by clients.
110 struct NotifyList *disconnect_notify_list_tail;
113 * Head of linked list of functions to call on connects by clients.
115 struct NotifyList *connect_notify_list_head;
118 * Tail of linked list of functions to call on connects by clients.
120 struct NotifyList *connect_notify_list_tail;
123 * Function to call for access control.
125 GNUNET_CONNECTION_AccessCheck access_cb;
128 * Closure for @e access_cb.
133 * NULL-terminated array of sockets used to listen for new
136 struct GNUNET_NETWORK_Handle **listen_sockets;
139 * After how long should an idle connection time
142 struct GNUNET_TIME_Relative idle_timeout;
145 * Task scheduled to do the listening.
147 struct GNUNET_SCHEDULER_Task *listen_task;
150 * Alternative function to create a MST instance.
152 GNUNET_SERVER_MstCreateCallback mst_create;
155 * Alternative function to destroy a MST instance.
157 GNUNET_SERVER_MstDestroyCallback mst_destroy;
160 * Alternative function to give data to a MST instance.
162 GNUNET_SERVER_MstReceiveCallback mst_receive;
165 * Closure for 'mst_'-callbacks.
170 * Do we ignore messages of types that we do not understand or do we
171 * require that a handler is found (and if not kill the connection)?
176 * Set to #GNUNET_YES once we are in 'soft' shutdown where we wait for
177 * all non-monitor clients to disconnect before we call
178 * #GNUNET_SERVER_destroy. See test_monitor_clients(). Set to
179 * #GNUNET_SYSERR once the final destroy task has been scheduled
180 * (we cannot run it in the same task).
182 int in_soft_shutdown;
187 * Handle server returns for aborting transmission to a client.
189 struct GNUNET_SERVER_TransmitHandle
192 * Function to call to get the message.
194 GNUNET_CONNECTION_TransmitReadyNotify callback;
197 * Closure for @e callback
202 * Active connection transmission handle.
204 struct GNUNET_CONNECTION_TransmitHandle *cth;
209 * @brief handle for a client of the server
211 struct GNUNET_SERVER_Client
214 * This is a doubly linked list.
216 struct GNUNET_SERVER_Client *next;
219 * This is a doubly linked list.
221 struct GNUNET_SERVER_Client *prev;
224 * Processing of incoming data.
229 * Server that this client belongs to.
231 struct GNUNET_SERVER_Handle *server;
234 * Client closure for callbacks.
236 struct GNUNET_CONNECTION_Handle *connection;
239 * User context value, manipulated using
240 * 'GNUNET_SERVER_client_{get/set}_user_context' functions.
245 * ID of task used to restart processing.
247 struct GNUNET_SCHEDULER_Task *restart_task;
250 * Task that warns about missing calls to #GNUNET_SERVER_receive_done.
252 struct GNUNET_SCHEDULER_Task *warn_task;
255 * Time when the warn task was started.
257 struct GNUNET_TIME_Absolute warn_start;
260 * Last activity on this socket (used to time it out
261 * if reference_count == 0).
263 struct GNUNET_TIME_Absolute last_activity;
266 * Transmission handle we return for this client from
267 * #GNUNET_SERVER_notify_transmit_ready.
269 struct GNUNET_SERVER_TransmitHandle th;
272 * After how long should an idle connection time
275 struct GNUNET_TIME_Relative idle_timeout;
278 * Number of external entities with a reference to
279 * this client object.
281 unsigned int reference_count;
284 * Was processing if incoming messages suspended while
285 * we were still processing data already received?
286 * This is a counter saying how often processing was
287 * suspended (once per handler invoked).
289 unsigned int suspended;
292 * Last size given when user context was initialized; used for
295 size_t user_context_size;
298 * Are we currently in the "process_client_buffer" function (and
299 * will hence restart the receive job on exit if suspended == 0 once
300 * we are done?). If this is set, then "receive_done" will
301 * essentially only decrement suspended; if this is not set, then
302 * "receive_done" may need to restart the receive process (either
303 * from the side-buffer or via select/recv).
305 int in_process_client_buffer;
308 * We're about to close down this client.
313 * Are we currently trying to receive? (#GNUNET_YES if we are,
314 * #GNUNET_NO if we are not, #GNUNET_SYSERR if data is already
320 * Persist the file handle for this client no matter what happens,
321 * force the OS to close once the process actually dies. Should only
322 * be used in special cases!
327 * Is this client a 'monitor' client that should not be counted
328 * when deciding on destroying the server during soft shutdown?
329 * (see also #GNUNET_SERVICE_start)
334 * Type of last message processed (for warn_no_receive_done).
342 * Return user context associated with the given client.
343 * Note: you should probably use the macro (call without the underscore).
345 * @param client client to query
346 * @param size number of bytes in user context struct (for verification only)
347 * @return pointer to user context
350 GNUNET_SERVER_client_get_user_context_ (struct GNUNET_SERVER_Client *client,
353 if ((0 == client->user_context_size) &&
354 (NULL == client->user_context))
355 return NULL; /* never set */
356 GNUNET_assert (size == client->user_context_size);
357 return client->user_context;
362 * Set user context to be associated with the given client.
363 * Note: you should probably use the macro (call without the underscore).
365 * @param client client to query
366 * @param ptr pointer to user context
367 * @param size number of bytes in user context struct (for verification only)
370 GNUNET_SERVER_client_set_user_context_ (struct GNUNET_SERVER_Client *client,
376 client->user_context_size = 0;
377 client->user_context = ptr;
380 client->user_context_size = size;
381 client->user_context = ptr;
386 * Scheduler says our listen socket is ready. Process it!
388 * @param cls handle to our server for which we are processing the listen
392 process_listen_socket (void *cls)
394 struct GNUNET_SERVER_Handle *server = cls;
395 const struct GNUNET_SCHEDULER_TaskContext *tc;
396 struct GNUNET_CONNECTION_Handle *sock;
399 server->listen_task = NULL;
400 tc = GNUNET_SCHEDULER_get_task_context ();
401 for (i = 0; NULL != server->listen_sockets[i]; i++)
403 if (GNUNET_NETWORK_fdset_isset (tc->read_ready,
404 server->listen_sockets[i]))
407 GNUNET_CONNECTION_create_from_accept (server->access_cb,
408 server->access_cb_cls,
409 server->listen_sockets[i]);
412 LOG (GNUNET_ERROR_TYPE_DEBUG,
413 "Server accepted incoming connection.\n");
414 (void) GNUNET_SERVER_connect_socket (server,
419 /* listen for more! */
420 GNUNET_SERVER_resume (server);
425 * Create and initialize a listen socket for the server.
427 * @param server_addr address to listen on
428 * @param socklen length of @a server_addr
429 * @return NULL on error, otherwise the listen socket
431 static struct GNUNET_NETWORK_Handle *
432 open_listen_socket (const struct sockaddr *server_addr,
435 struct GNUNET_NETWORK_Handle *sock;
439 switch (server_addr->sa_family)
442 port = ntohs (((const struct sockaddr_in *) server_addr)->sin_port);
446 port = ntohs (((const struct sockaddr_in6 *) server_addr)->sin6_port);
458 sock = GNUNET_NETWORK_socket_create (server_addr->sa_family, SOCK_STREAM, 0);
461 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "socket");
465 /* bind the socket */
466 if (GNUNET_OK != GNUNET_NETWORK_socket_bind (sock, server_addr, socklen))
469 if (EADDRINUSE != errno)
471 /* we don't log 'EADDRINUSE' here since an IPv4 bind may
472 * fail if we already took the port on IPv6; if both IPv4 and
473 * IPv6 binds fail, then our caller will log using the
474 * errno preserved in 'eno' */
475 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR,
478 LOG (GNUNET_ERROR_TYPE_ERROR,
479 _ ("`%s' failed for port %d (%s).\n"),
482 (AF_INET == server_addr->sa_family) ? "IPv4" : "IPv6");
488 LOG (GNUNET_ERROR_TYPE_WARNING,
489 _ ("`%s' failed for port %d (%s): address already in use\n"),
491 (AF_INET == server_addr->sa_family) ? "IPv4" : "IPv6");
492 else if (AF_UNIX == server_addr->sa_family)
494 LOG (GNUNET_ERROR_TYPE_WARNING,
495 _ ("`%s' failed for `%s': address already in use\n"),
497 GNUNET_a2s (server_addr, socklen));
500 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (sock));
504 if (GNUNET_OK != GNUNET_NETWORK_socket_listen (sock, 5))
506 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR,
508 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (sock));
513 LOG (GNUNET_ERROR_TYPE_DEBUG,
514 "Server starts to listen on port %u.\n",
521 * Create a new server.
523 * @param access_cb function for access control
524 * @param access_cb_cls closure for @a access_cb
525 * @param lsocks NULL-terminated array of listen sockets
526 * @param idle_timeout after how long should we timeout idle connections?
527 * @param require_found if #GNUNET_YES, connections sending messages of unknown type
529 * @return handle for the new server, NULL on error
530 * (typically, "port" already in use)
532 struct GNUNET_SERVER_Handle *
533 GNUNET_SERVER_create_with_sockets (GNUNET_CONNECTION_AccessCheck access_cb,
535 struct GNUNET_NETWORK_Handle **lsocks,
536 struct GNUNET_TIME_Relative idle_timeout,
539 struct GNUNET_SERVER_Handle *server;
541 server = GNUNET_new (struct GNUNET_SERVER_Handle);
542 server->idle_timeout = idle_timeout;
543 server->listen_sockets = lsocks;
544 server->access_cb = access_cb;
545 server->access_cb_cls = access_cb_cls;
546 server->require_found = require_found;
548 GNUNET_SERVER_resume (server);
554 * Create a new server.
556 * @param access_cb function for access control
557 * @param access_cb_cls closure for @a access_cb
558 * @param server_addr address to listen on (including port), NULL terminated array
559 * @param socklen length of server_addr
560 * @param idle_timeout after how long should we timeout idle connections?
561 * @param require_found if YES, connections sending messages of unknown type
563 * @return handle for the new server, NULL on error
564 * (typically, "port" already in use)
566 struct GNUNET_SERVER_Handle *
567 GNUNET_SERVER_create (GNUNET_CONNECTION_AccessCheck access_cb,
569 struct sockaddr *const *server_addr,
570 const socklen_t *socklen,
571 struct GNUNET_TIME_Relative idle_timeout,
574 struct GNUNET_NETWORK_Handle **lsocks;
581 while (NULL != server_addr[i])
585 lsocks = GNUNET_malloc (sizeof(struct GNUNET_NETWORK_Handle *) * (i + 1));
588 while (NULL != server_addr[i])
591 for (k = 0; k < i; k++)
592 if ((socklen[k] == socklen[i]) &&
593 (0 == memcmp (server_addr[k], server_addr[i], socklen[i])))
600 /* duplicate address, skip */
604 lsocks[j] = open_listen_socket (server_addr[i], socklen[i]);
605 if (NULL != lsocks[j])
612 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "bind");
613 GNUNET_free (lsocks);
621 return GNUNET_SERVER_create_with_sockets (access_cb,
630 * Set the 'monitor' flag on this client. Clients which have been
631 * marked as 'monitors' won't prevent the server from shutting down
632 * once '#GNUNET_SERVER_stop_listening()' has been invoked. The idea is
633 * that for "normal" clients we likely want to allow them to process
634 * their requests; however, monitor-clients are likely to 'never'
635 * disconnect during shutdown and thus will not be considered when
636 * determining if the server should continue to exist after
637 * #GNUNET_SERVER_destroy() has been called.
639 * @param client the client to set the 'monitor' flag on
642 GNUNET_SERVER_client_mark_monitor (struct GNUNET_SERVER_Client *client)
644 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
645 "Marking client as monitor!\n");
646 client->is_monitor = GNUNET_YES;
651 * Helper function for #test_monitor_clients() to trigger
652 * #GNUNET_SERVER_destroy() after the stack has unwound.
654 * @param cls the `struct GNUNET_SERVER_Handle *` to destroy
657 do_destroy (void *cls)
659 struct GNUNET_SERVER_Handle *server = cls;
661 GNUNET_SERVER_destroy (server);
666 * Check if only 'monitor' clients are left. If so, destroy the
669 * @param server server to test for full shutdown
672 test_monitor_clients (struct GNUNET_SERVER_Handle *server)
674 struct GNUNET_SERVER_Client *client;
676 if (GNUNET_YES != server->in_soft_shutdown)
678 for (client = server->clients_head; NULL != client; client = client->next)
679 if (GNUNET_NO == client->is_monitor)
682 server->in_soft_shutdown = GNUNET_SYSERR;
683 (void) GNUNET_SCHEDULER_add_now (&do_destroy, server);
688 * Suspend accepting connections from the listen socket temporarily.
690 * @param server server to stop accepting connections.
693 GNUNET_SERVER_suspend (struct GNUNET_SERVER_Handle *server)
695 if (NULL != server->listen_task)
697 GNUNET_SCHEDULER_cancel (server->listen_task);
698 server->listen_task = NULL;
704 * Resume accepting connections from the listen socket.
706 * @param server server to stop accepting connections.
709 GNUNET_SERVER_resume (struct GNUNET_SERVER_Handle *server)
711 struct GNUNET_NETWORK_FDSet *r;
714 if (NULL == server->listen_sockets)
716 if (NULL == server->listen_sockets[0])
717 return; /* nothing to do, no listen sockets! */
718 if (NULL == server->listen_sockets[1])
720 /* simplified method: no fd set needed; this is then much simpler
721 and much more efficient */
722 server->listen_task =
723 GNUNET_SCHEDULER_add_read_net_with_priority (GNUNET_TIME_UNIT_FOREVER_REL,
724 GNUNET_SCHEDULER_PRIORITY_HIGH,
725 server->listen_sockets[0],
726 &process_listen_socket,
730 r = GNUNET_NETWORK_fdset_create ();
732 while (NULL != server->listen_sockets[i])
733 GNUNET_NETWORK_fdset_set (r, server->listen_sockets[i++]);
734 server->listen_task =
735 GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_HIGH,
736 GNUNET_TIME_UNIT_FOREVER_REL, r, NULL,
737 &process_listen_socket, server);
738 GNUNET_NETWORK_fdset_destroy (r);
743 * Stop the listen socket and get ready to shutdown the server
744 * once only 'monitor' clients are left.
746 * @param server server to stop listening on
749 GNUNET_SERVER_stop_listening (struct GNUNET_SERVER_Handle *server)
753 LOG (GNUNET_ERROR_TYPE_DEBUG,
754 "Server in soft shutdown\n");
755 if (NULL != server->listen_task)
757 GNUNET_SCHEDULER_cancel (server->listen_task);
758 server->listen_task = NULL;
760 if (NULL != server->listen_sockets)
763 while (NULL != server->listen_sockets[i])
764 GNUNET_break (GNUNET_OK ==
765 GNUNET_NETWORK_socket_close (server->listen_sockets[i++]));
766 GNUNET_free (server->listen_sockets);
767 server->listen_sockets = NULL;
769 if (GNUNET_NO == server->in_soft_shutdown)
770 server->in_soft_shutdown = GNUNET_YES;
771 test_monitor_clients (server);
776 * Free resources held by this server.
778 * @param server server to destroy
781 GNUNET_SERVER_destroy (struct GNUNET_SERVER_Handle *server)
783 struct HandlerList *hpos;
784 struct NotifyList *npos;
787 LOG (GNUNET_ERROR_TYPE_DEBUG,
788 "Server shutting down.\n");
789 if (NULL != server->listen_task)
791 GNUNET_SCHEDULER_cancel (server->listen_task);
792 server->listen_task = NULL;
794 if (NULL != server->listen_sockets)
797 while (NULL != server->listen_sockets[i])
798 GNUNET_break (GNUNET_OK ==
799 GNUNET_NETWORK_socket_close (server->listen_sockets[i++]));
800 GNUNET_free (server->listen_sockets);
801 server->listen_sockets = NULL;
803 while (NULL != server->clients_head)
804 GNUNET_SERVER_client_disconnect (server->clients_head);
805 while (NULL != (hpos = server->handlers))
807 server->handlers = hpos->next;
810 while (NULL != (npos = server->disconnect_notify_list_head))
812 npos->callback (npos->callback_cls,
814 GNUNET_CONTAINER_DLL_remove (server->disconnect_notify_list_head,
815 server->disconnect_notify_list_tail,
819 while (NULL != (npos = server->connect_notify_list_head))
821 npos->callback (npos->callback_cls,
823 GNUNET_CONTAINER_DLL_remove (server->connect_notify_list_head,
824 server->connect_notify_list_tail,
828 GNUNET_free (server);
833 * Add additional handlers to an existing server.
835 * @param server the server to add handlers to
836 * @param handlers array of message handlers for
837 * incoming messages; the last entry must
838 * have "NULL" for the "callback"; multiple
839 * entries for the same type are allowed,
840 * they will be called in order of occurence.
841 * These handlers can be removed later;
842 * the handlers array must exist until removed
843 * (or server is destroyed).
846 GNUNET_SERVER_add_handlers (struct GNUNET_SERVER_Handle *server,
847 const struct GNUNET_SERVER_MessageHandler *handlers)
849 struct HandlerList *p;
851 p = GNUNET_new (struct HandlerList);
852 p->handlers = handlers;
853 p->next = server->handlers;
854 server->handlers = p;
859 * Change functions used by the server to tokenize the message stream.
860 * (very rarely used).
862 * @param server server to modify
863 * @param create new tokenizer initialization function
864 * @param destroy new tokenizer destruction function
865 * @param receive new tokenizer receive function
866 * @param cls closure for @a create, @a receive, @a destroy
869 GNUNET_SERVER_set_callbacks (struct GNUNET_SERVER_Handle *server,
870 GNUNET_SERVER_MstCreateCallback create,
871 GNUNET_SERVER_MstDestroyCallback destroy,
872 GNUNET_SERVER_MstReceiveCallback receive,
875 server->mst_create = create;
876 server->mst_destroy = destroy;
877 server->mst_receive = receive;
878 server->mst_cls = cls;
883 * Task run to warn about missing calls to #GNUNET_SERVER_receive_done.
885 * @param cls our `struct GNUNET_SERVER_Client *` to process more requests from
888 warn_no_receive_done (void *cls)
890 struct GNUNET_SERVER_Client *client = cls;
892 GNUNET_break (0 != client->warn_type); /* type should never be 0 here, as we don't use 0 */
894 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES,
895 &warn_no_receive_done, client);
896 LOG (GNUNET_ERROR_TYPE_WARNING,
898 "Processing code for message of type %u did not call `GNUNET_SERVER_receive_done' after %s\n"),
899 (unsigned int) client->warn_type,
900 GNUNET_STRINGS_relative_time_to_string (
901 GNUNET_TIME_absolute_get_duration (client->warn_start),
907 * Disable the warning the server issues if a message is not acknowledged
908 * in a timely fashion. Use this call if a client is intentionally delayed
909 * for a while. Only applies to the current message.
911 * @param client client for which to disable the warning
914 GNUNET_SERVER_disable_receive_done_warning (struct GNUNET_SERVER_Client *client)
916 if (NULL != client->warn_task)
918 GNUNET_SCHEDULER_cancel (client->warn_task);
919 client->warn_task = NULL;
925 * Inject a message into the server, pretend it came
926 * from the specified client. Delivery of the message
927 * will happen instantly (if a handler is installed;
928 * otherwise the call does nothing).
930 * @param server the server receiving the message
931 * @param sender the "pretended" sender of the message
933 * @param message message to transmit
934 * @return #GNUNET_OK if the message was OK and the
935 * connection can stay open
936 * #GNUNET_SYSERR if the connection to the
937 * client should be shut down
940 GNUNET_SERVER_inject (struct GNUNET_SERVER_Handle *server,
941 struct GNUNET_SERVER_Client *sender,
942 const struct GNUNET_MessageHeader *message)
944 struct HandlerList *pos;
945 const struct GNUNET_SERVER_MessageHandler *mh;
951 type = ntohs (message->type);
952 size = ntohs (message->size);
953 LOG (GNUNET_ERROR_TYPE_INFO,
954 "Received message of type %u and size %u from client\n",
957 for (pos = server->handlers; NULL != pos; pos = pos->next)
960 while (pos->handlers[i].callback != NULL)
962 mh = &pos->handlers[i];
963 if ((mh->type == type) || (mh->type == GNUNET_MESSAGE_TYPE_ALL))
965 if ((0 != mh->expected_size) && (mh->expected_size != size))
967 #if GNUNET8_NETWORK_IS_DEAD
968 LOG (GNUNET_ERROR_TYPE_WARNING,
969 "Expected %u bytes for message of type %u, got %u\n",
970 mh->expected_size, mh->type, size);
973 LOG (GNUNET_ERROR_TYPE_DEBUG,
974 "Expected %u bytes for message of type %u, got %u\n",
975 mh->expected_size, mh->type, size);
977 return GNUNET_SYSERR;
981 if ((0 == sender->suspended) &&
982 (NULL == sender->warn_task))
984 GNUNET_break (0 != type); /* type should never be 0 here, as we don't use 0 */
985 sender->warn_start = GNUNET_TIME_absolute_get ();
987 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES,
988 &warn_no_receive_done,
990 sender->warn_type = type;
994 mh->callback (mh->callback_cls, sender, message);
1000 if (GNUNET_NO == found)
1002 LOG (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1003 "Received message of unknown type %d\n", type);
1004 if (GNUNET_YES == server->require_found)
1005 return GNUNET_SYSERR;
1012 * We are receiving an incoming message. Process it.
1014 * @param cls our closure (handle for the client)
1015 * @param buf buffer with data received from network
1016 * @param available number of bytes available in buf
1017 * @param addr address of the sender
1018 * @param addrlen length of @a addr
1019 * @param errCode code indicating errors receiving, 0 for success
1022 process_incoming (void *cls,
1025 const struct sockaddr *addr,
1031 * Process messages from the client's message tokenizer until either
1032 * the tokenizer is empty (and then schedule receiving more), or
1033 * until some handler is not immediately done (then wait for restart_processing)
1036 * @param client the client to process, RC must have already been increased
1037 * using #GNUNET_SERVER_client_keep and will be decreased by one in this
1039 * @param ret #GNUNET_NO to start processing from the buffer,
1040 * #GNUNET_OK if the mst buffer is drained and we should instantly go back to receiving
1041 * #GNUNET_SYSERR if we should instantly abort due to error in a previous step
1044 process_mst (struct GNUNET_SERVER_Client *client,
1047 while ((GNUNET_SYSERR != ret) && (NULL != client->server) &&
1048 (GNUNET_YES != client->shutdown_now) && (0 == client->suspended))
1050 if (GNUNET_OK == ret)
1052 LOG (GNUNET_ERROR_TYPE_DEBUG,
1053 "Server re-enters receive loop, timeout: %s.\n",
1054 GNUNET_STRINGS_relative_time_to_string (client->idle_timeout,
1056 client->receive_pending = GNUNET_YES;
1058 GNUNET_CONNECTION_receive (client->connection,
1059 GNUNET_MAX_MESSAGE_SIZE - 1,
1060 client->idle_timeout,
1066 LOG (GNUNET_ERROR_TYPE_DEBUG,
1067 "Server processes additional messages instantly.\n");
1068 if (NULL != client->server->mst_receive)
1070 client->server->mst_receive (client->server->mst_cls, client->mst,
1071 client, NULL, 0, GNUNET_NO, GNUNET_YES);
1074 GNUNET_SERVER_mst_receive (client->mst, client, NULL, 0, GNUNET_NO,
1077 LOG (GNUNET_ERROR_TYPE_DEBUG,
1078 "Server leaves instant processing loop: ret = %d, server = %p, shutdown = %d, suspended = %u\n",
1079 ret, client->server,
1080 client->shutdown_now,
1082 if (GNUNET_NO == ret)
1084 LOG (GNUNET_ERROR_TYPE_DEBUG,
1085 "Server has more data pending but is suspended.\n");
1086 client->receive_pending = GNUNET_SYSERR; /* data pending */
1088 if ((GNUNET_SYSERR == ret) ||
1089 (GNUNET_YES == client->shutdown_now))
1090 GNUNET_SERVER_client_disconnect (client);
1095 * We are receiving an incoming message. Process it.
1097 * @param cls our closure (handle for the client)
1098 * @param buf buffer with data received from network
1099 * @param available number of bytes available in buf
1100 * @param addr address of the sender
1101 * @param addrlen length of @a addr
1102 * @param errCode code indicating errors receiving, 0 for success
1105 process_incoming (void *cls,
1108 const struct sockaddr *addr,
1112 struct GNUNET_SERVER_Client *client = cls;
1113 struct GNUNET_SERVER_Handle *server = client->server;
1114 struct GNUNET_TIME_Absolute end;
1115 struct GNUNET_TIME_Absolute now;
1118 GNUNET_assert (GNUNET_YES == client->receive_pending);
1119 client->receive_pending = GNUNET_NO;
1120 now = GNUNET_TIME_absolute_get ();
1121 end = GNUNET_TIME_absolute_add (client->last_activity,
1122 client->idle_timeout);
1124 if ((NULL == buf) &&
1128 (GNUNET_YES != client->shutdown_now) &&
1130 (GNUNET_YES == GNUNET_CONNECTION_check (client->connection)) &&
1131 (end.abs_value_us > now.abs_value_us))
1133 /* wait longer, timeout changed (i.e. due to us sending) */
1134 LOG (GNUNET_ERROR_TYPE_DEBUG,
1135 "Receive time out, but no disconnect due to sending (%p)\n",
1137 client->receive_pending = GNUNET_YES;
1138 GNUNET_CONNECTION_receive (client->connection,
1139 GNUNET_MAX_MESSAGE_SIZE - 1,
1140 GNUNET_TIME_absolute_get_remaining (end),
1145 if ((NULL == buf) ||
1149 (GNUNET_YES == client->shutdown_now) ||
1150 (GNUNET_YES != GNUNET_CONNECTION_check (client->connection)))
1152 /* other side closed connection, error connecting, etc. */
1153 LOG (GNUNET_ERROR_TYPE_DEBUG,
1154 "Failed to connect or other side closed connection (%p)\n",
1156 GNUNET_SERVER_client_disconnect (client);
1159 LOG (GNUNET_ERROR_TYPE_DEBUG,
1160 "Server receives %u bytes from `%s'.\n",
1161 (unsigned int) available,
1162 GNUNET_a2s (addr, addrlen));
1163 GNUNET_SERVER_client_keep (client);
1164 client->last_activity = now;
1166 if (NULL != server->mst_receive)
1168 ret = client->server->mst_receive (client->server->mst_cls,
1176 else if (NULL != client->mst)
1179 GNUNET_SERVER_mst_receive (client->mst,
1191 process_mst (client,
1193 GNUNET_SERVER_client_drop (client);
1198 * Task run to start again receiving from the network
1199 * and process requests.
1201 * @param cls our `struct GNUNET_SERVER_Client *` to process more requests from
1204 restart_processing (void *cls)
1206 struct GNUNET_SERVER_Client *client = cls;
1208 GNUNET_assert (GNUNET_YES != client->shutdown_now);
1209 client->restart_task = NULL;
1210 if (GNUNET_NO == client->receive_pending)
1212 LOG (GNUNET_ERROR_TYPE_DEBUG, "Server begins to read again from client.\n");
1213 client->receive_pending = GNUNET_YES;
1214 GNUNET_CONNECTION_receive (client->connection,
1215 GNUNET_MAX_MESSAGE_SIZE - 1,
1216 client->idle_timeout,
1221 LOG (GNUNET_ERROR_TYPE_DEBUG,
1222 "Server continues processing messages still in the buffer.\n");
1223 GNUNET_SERVER_client_keep (client);
1224 client->receive_pending = GNUNET_NO;
1225 process_mst (client,
1227 GNUNET_SERVER_client_drop (client);
1232 * This function is called whenever our inbound message tokenizer has
1233 * received a complete message.
1235 * @param cls closure (struct GNUNET_SERVER_Handle)
1236 * @param client identification of the client (`struct GNUNET_SERVER_Client *`)
1237 * @param message the actual message
1239 * @return #GNUNET_OK on success, #GNUNET_SYSERR to stop further processing
1242 client_message_tokenizer_callback (void *cls,
1244 const struct GNUNET_MessageHeader *message)
1246 struct GNUNET_SERVER_Handle *server = cls;
1247 struct GNUNET_SERVER_Client *sender = client;
1250 LOG (GNUNET_ERROR_TYPE_DEBUG,
1251 "Tokenizer gives server message of type %u and size %u from client\n",
1252 ntohs (message->type), ntohs (message->size));
1253 sender->in_process_client_buffer = GNUNET_YES;
1254 ret = GNUNET_SERVER_inject (server, sender, message);
1255 sender->in_process_client_buffer = GNUNET_NO;
1256 if ((GNUNET_OK != ret) || (GNUNET_YES == sender->shutdown_now))
1258 GNUNET_SERVER_client_disconnect (sender);
1259 return GNUNET_SYSERR;
1266 * Add a TCP socket-based connection to the set of handles managed by
1267 * this server. Use this function for outgoing (P2P) connections that
1268 * we initiated (and where this server should process incoming
1271 * @param server the server to use
1272 * @param connection the connection to manage (client must
1273 * stop using this connection from now on)
1274 * @return the client handle
1276 struct GNUNET_SERVER_Client *
1277 GNUNET_SERVER_connect_socket (struct GNUNET_SERVER_Handle *server,
1278 struct GNUNET_CONNECTION_Handle *connection)
1280 struct GNUNET_SERVER_Client *client;
1281 struct NotifyList *n;
1283 client = GNUNET_new (struct GNUNET_SERVER_Client);
1284 client->connection = connection;
1285 client->server = server;
1286 client->last_activity = GNUNET_TIME_absolute_get ();
1287 client->idle_timeout = server->idle_timeout;
1288 GNUNET_CONTAINER_DLL_insert (server->clients_head,
1289 server->clients_tail,
1291 if (NULL != server->mst_create)
1293 server->mst_create (server->mst_cls, client);
1296 GNUNET_SERVER_mst_create (&client_message_tokenizer_callback,
1298 GNUNET_assert (NULL != client->mst);
1299 for (n = server->connect_notify_list_head; NULL != n; n = n->next)
1300 n->callback (n->callback_cls, client);
1301 client->receive_pending = GNUNET_YES;
1302 if (GNUNET_SYSERR ==
1303 GNUNET_CONNECTION_receive (client->connection,
1304 GNUNET_MAX_MESSAGE_SIZE - 1,
1305 client->idle_timeout,
1314 * Change the timeout for a particular client. Decreasing the timeout
1315 * may not go into effect immediately (only after the previous timeout
1316 * times out or activity happens on the socket).
1318 * @param client the client to update
1319 * @param timeout new timeout for activities on the socket
1322 GNUNET_SERVER_client_set_timeout (struct GNUNET_SERVER_Client *client,
1323 struct GNUNET_TIME_Relative timeout)
1325 client->idle_timeout = timeout;
1330 * Notify the server that the given client handle should
1331 * be kept (keeps the connection up if possible, increments
1332 * the internal reference counter).
1334 * @param client the client to keep
1337 GNUNET_SERVER_client_keep (struct GNUNET_SERVER_Client *client)
1339 client->reference_count++;
1344 * Notify the server that the given client handle is no
1345 * longer required. Decrements the reference counter. If
1346 * that counter reaches zero an inactive connection maybe
1349 * @param client the client to drop
1352 GNUNET_SERVER_client_drop (struct GNUNET_SERVER_Client *client)
1354 GNUNET_assert (client->reference_count > 0);
1355 client->reference_count--;
1356 if ((GNUNET_YES == client->shutdown_now) && (0 == client->reference_count))
1357 GNUNET_SERVER_client_disconnect (client);
1362 * Obtain the network address of the other party.
1364 * @param client the client to get the address for
1365 * @param addr where to store the address
1366 * @param addrlen where to store the length of the @a addr
1367 * @return #GNUNET_OK on success
1370 GNUNET_SERVER_client_get_address (struct GNUNET_SERVER_Client *client,
1371 void **addr, size_t *addrlen)
1373 return GNUNET_CONNECTION_get_address (client->connection, addr, addrlen);
1378 * Ask the server to notify us whenever a client disconnects.
1379 * This function is called whenever the actual network connection
1380 * is closed; the reference count may be zero or larger than zero
1383 * @param server the server manageing the clients
1384 * @param callback function to call on disconnect
1385 * @param callback_cls closure for @a callback
1388 GNUNET_SERVER_disconnect_notify (struct GNUNET_SERVER_Handle *server,
1389 GNUNET_SERVER_DisconnectCallback callback,
1392 struct NotifyList *n;
1394 n = GNUNET_new (struct NotifyList);
1395 n->callback = callback;
1396 n->callback_cls = callback_cls;
1397 GNUNET_CONTAINER_DLL_insert (server->disconnect_notify_list_head,
1398 server->disconnect_notify_list_tail,
1404 * Ask the server to notify us whenever a client connects.
1405 * This function is called whenever the actual network connection
1406 * is opened. If the server is destroyed before this
1407 * notification is explicitly cancelled, the 'callback' will
1408 * once be called with a 'client' argument of NULL to indicate
1409 * that the server itself is now gone (and that the callback
1410 * won't be called anymore and also can no longer be cancelled).
1412 * @param server the server manageing the clients
1413 * @param callback function to call on sconnect
1414 * @param callback_cls closure for @a callback
1417 GNUNET_SERVER_connect_notify (struct GNUNET_SERVER_Handle *server,
1418 GNUNET_SERVER_ConnectCallback callback,
1421 struct NotifyList *n;
1422 struct GNUNET_SERVER_Client *client;
1424 n = GNUNET_new (struct NotifyList);
1425 n->callback = callback;
1426 n->callback_cls = callback_cls;
1427 GNUNET_CONTAINER_DLL_insert (server->connect_notify_list_head,
1428 server->connect_notify_list_tail,
1430 for (client = server->clients_head; NULL != client; client = client->next)
1431 callback (callback_cls, client);
1436 * Ask the server to stop notifying us whenever a client connects.
1438 * @param server the server manageing the clients
1439 * @param callback function to call on connect
1440 * @param callback_cls closure for @a callback
1443 GNUNET_SERVER_disconnect_notify_cancel (struct GNUNET_SERVER_Handle *server,
1444 GNUNET_SERVER_DisconnectCallback
1448 struct NotifyList *pos;
1450 for (pos = server->disconnect_notify_list_head; NULL != pos; pos = pos->next)
1451 if ((pos->callback == callback) && (pos->callback_cls == callback_cls))
1458 GNUNET_CONTAINER_DLL_remove (server->disconnect_notify_list_head,
1459 server->disconnect_notify_list_tail,
1466 * Ask the server to stop notifying us whenever a client disconnects.
1468 * @param server the server manageing the clients
1469 * @param callback function to call on disconnect
1470 * @param callback_cls closure for @a callback
1473 GNUNET_SERVER_connect_notify_cancel (struct GNUNET_SERVER_Handle *server,
1474 GNUNET_SERVER_ConnectCallback callback,
1477 struct NotifyList *pos;
1479 for (pos = server->connect_notify_list_head; NULL != pos; pos = pos->next)
1480 if ((pos->callback == callback) && (pos->callback_cls == callback_cls))
1487 GNUNET_CONTAINER_DLL_remove (server->connect_notify_list_head,
1488 server->connect_notify_list_tail,
1495 * Ask the server to disconnect from the given client.
1496 * This is the same as returning #GNUNET_SYSERR from a message
1497 * handler, except that it allows dropping of a client even
1498 * when not handling a message from that client.
1500 * @param client the client to disconnect from
1503 GNUNET_SERVER_client_disconnect (struct GNUNET_SERVER_Client *client)
1505 struct GNUNET_SERVER_Handle *server = client->server;
1506 struct NotifyList *n;
1508 LOG (GNUNET_ERROR_TYPE_DEBUG,
1509 "Client is being disconnected from the server.\n");
1510 if (NULL != client->restart_task)
1512 GNUNET_SCHEDULER_cancel (client->restart_task);
1513 client->restart_task = NULL;
1515 if (NULL != client->warn_task)
1517 GNUNET_SCHEDULER_cancel (client->warn_task);
1518 client->warn_task = NULL;
1520 if (GNUNET_YES == client->receive_pending)
1522 GNUNET_CONNECTION_receive_cancel (client->connection);
1523 client->receive_pending = GNUNET_NO;
1525 client->shutdown_now = GNUNET_YES;
1526 client->reference_count++; /* make sure nobody else clean up client... */
1527 if ((NULL != client->mst) &&
1530 GNUNET_CONTAINER_DLL_remove (server->clients_head,
1531 server->clients_tail,
1533 if (NULL != server->mst_destroy)
1534 server->mst_destroy (server->mst_cls,
1537 GNUNET_SERVER_mst_destroy (client->mst);
1539 for (n = server->disconnect_notify_list_head; NULL != n; n = n->next)
1540 n->callback (n->callback_cls,
1543 client->reference_count--;
1544 if (client->reference_count > 0)
1546 LOG (GNUNET_ERROR_TYPE_DEBUG,
1547 "RC of %p still positive, not destroying everything.\n",
1549 client->server = NULL;
1552 if (GNUNET_YES == client->in_process_client_buffer)
1554 LOG (GNUNET_ERROR_TYPE_DEBUG,
1555 "Still processing inputs of %p, not destroying everything.\n",
1559 LOG (GNUNET_ERROR_TYPE_DEBUG,
1560 "RC of %p now zero, destroying everything.\n",
1562 if (GNUNET_YES == client->persist)
1563 GNUNET_CONNECTION_persist_ (client->connection);
1564 if (NULL != client->th.cth)
1565 GNUNET_SERVER_notify_transmit_ready_cancel (&client->th);
1566 GNUNET_CONNECTION_destroy (client->connection);
1567 /* need to cancel again, as it might have been re-added
1568 in the meantime (i.e. during callbacks) */
1569 if (NULL != client->warn_task)
1571 GNUNET_SCHEDULER_cancel (client->warn_task);
1572 client->warn_task = NULL;
1574 if (GNUNET_YES == client->receive_pending)
1576 GNUNET_CONNECTION_receive_cancel (client->connection);
1577 client->receive_pending = GNUNET_NO;
1579 GNUNET_free (client);
1580 /* we might be in soft-shutdown, test if we're done */
1582 test_monitor_clients (server);
1587 * Disable the "CORK" feature for communication with the given client,
1588 * forcing the OS to immediately flush the buffer on transmission
1589 * instead of potentially buffering multiple messages.
1591 * @param client handle to the client
1592 * @return #GNUNET_OK on success
1595 GNUNET_SERVER_client_disable_corking (struct GNUNET_SERVER_Client *client)
1597 return GNUNET_CONNECTION_disable_corking (client->connection);
1602 * Wrapper for transmission notification that calls the original
1603 * callback and update the last activity time for our connection.
1605 * @param cls the `struct GNUNET_SERVER_Client *`
1606 * @param size number of bytes we can transmit
1607 * @param buf where to copy the message
1608 * @return number of bytes actually transmitted
1611 transmit_ready_callback_wrapper (void *cls, size_t size, void *buf)
1613 struct GNUNET_SERVER_Client *client = cls;
1614 GNUNET_CONNECTION_TransmitReadyNotify callback;
1616 client->th.cth = NULL;
1617 callback = client->th.callback;
1618 client->th.callback = NULL;
1619 client->last_activity = GNUNET_TIME_absolute_get ();
1620 return callback (client->th.callback_cls, size, buf);
1625 * Notify us when the server has enough space to transmit
1626 * a message of the given size to the given client.
1628 * @param client client to transmit message to
1629 * @param size requested amount of buffer space
1630 * @param timeout after how long should we give up (and call
1631 * notify with buf NULL and size 0)?
1632 * @param callback function to call when space is available
1633 * @param callback_cls closure for @a callback
1634 * @return non-NULL if the notify callback was queued; can be used
1635 * to cancel the request using
1636 * #GNUNET_SERVER_notify_transmit_ready_cancel().
1637 * NULL if we are already going to notify someone else (busy)
1639 struct GNUNET_SERVER_TransmitHandle *
1640 GNUNET_SERVER_notify_transmit_ready (struct GNUNET_SERVER_Client *client,
1642 struct GNUNET_TIME_Relative timeout,
1643 GNUNET_CONNECTION_TransmitReadyNotify
1647 if (NULL != client->th.callback)
1649 client->th.callback_cls = callback_cls;
1650 client->th.callback = callback;
1651 client->th.cth = GNUNET_CONNECTION_notify_transmit_ready (client->connection,
1655 transmit_ready_callback_wrapper,
1662 * Abort transmission request.
1664 * @param th request to abort
1667 GNUNET_SERVER_notify_transmit_ready_cancel (struct
1668 GNUNET_SERVER_TransmitHandle *th)
1670 GNUNET_CONNECTION_notify_transmit_ready_cancel (th->cth);
1672 th->callback = NULL;
1677 * Set the persistent flag on this client, used to setup client connection
1678 * to only be killed when the service it's connected to is actually dead.
1680 * @param client the client to set the persistent flag on
1683 GNUNET_SERVER_client_persist_ (struct GNUNET_SERVER_Client *client)
1685 client->persist = GNUNET_YES;
1690 * Resume receiving from this client, we are done processing the
1691 * current request. This function must be called from within each
1692 * GNUNET_SERVER_MessageCallback (or its respective continuations).
1694 * @param client client we were processing a message of
1695 * @param success #GNUNET_OK to keep the connection open and
1696 * continue to receive
1697 * #GNUNET_NO to close the connection (normal behavior)
1698 * #GNUNET_SYSERR to close the connection (signal
1702 GNUNET_SERVER_receive_done (struct GNUNET_SERVER_Client *client,
1707 GNUNET_assert (client->suspended > 0);
1708 client->suspended--;
1709 if (GNUNET_OK != success)
1711 LOG (GNUNET_ERROR_TYPE_DEBUG,
1712 "GNUNET_SERVER_receive_done called with failure indication\n");
1713 if ((client->reference_count > 0) || (client->suspended > 0))
1714 client->shutdown_now = GNUNET_YES;
1716 GNUNET_SERVER_client_disconnect (client);
1719 if (client->suspended > 0)
1721 LOG (GNUNET_ERROR_TYPE_DEBUG,
1722 "GNUNET_SERVER_receive_done called, but more clients pending\n");
1725 if (NULL != client->warn_task)
1727 GNUNET_SCHEDULER_cancel (client->warn_task);
1728 client->warn_task = NULL;
1730 if (GNUNET_YES == client->in_process_client_buffer)
1732 LOG (GNUNET_ERROR_TYPE_DEBUG,
1733 "GNUNET_SERVER_receive_done called while still in processing loop\n");
1736 if ((NULL == client->server) || (GNUNET_YES == client->shutdown_now))
1738 GNUNET_SERVER_client_disconnect (client);
1741 LOG (GNUNET_ERROR_TYPE_DEBUG,
1742 "GNUNET_SERVER_receive_done causes restart in reading from the socket\n");
1743 GNUNET_assert (NULL == client->restart_task);
1744 client->restart_task = GNUNET_SCHEDULER_add_now (&restart_processing,
1749 /* end of server.c */