2 This file is part of GNUnet.
3 (C) 2009, 2012 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 2, or (at your
8 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 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
23 * @brief library for building GNUnet network servers
24 * @author Christian Grothoff
28 #include "gnunet_common.h"
29 #include "gnunet_util_lib.h"
30 #include "gnunet_protocols.h"
32 #define LOG(kind,...) GNUNET_log_from (kind, "util", __VA_ARGS__)
34 #define LOG_STRERROR(kind,syscall) GNUNET_log_from_strerror (kind, "util", syscall)
36 #define LOG_STRERROR_FILE(kind,syscall,filename) GNUNET_log_from_strerror_file (kind, "util", syscall, filename)
40 * List of arrays of message handlers.
45 * This is a linked list.
47 struct HandlerList *next;
50 * NULL-terminated array of handlers.
52 const struct GNUNET_SERVER_MessageHandler *handlers;
57 * List of arrays of message handlers.
62 * This is a doubly linked list.
64 struct NotifyList *next;
67 * This is a doubly linked list.
69 struct NotifyList *prev;
74 GNUNET_SERVER_DisconnectCallback callback;
77 * Closure for callback.
84 * @brief handle for a server
86 struct GNUNET_SERVER_Handle
89 * List of handlers for incoming messages.
91 struct HandlerList *handlers;
94 * Head of list of our current clients.
96 struct GNUNET_SERVER_Client *clients_head;
99 * Head of list of our current clients.
101 struct GNUNET_SERVER_Client *clients_tail;
104 * Head of linked list of functions to call on disconnects by clients.
106 struct NotifyList *disconnect_notify_list_head;
109 * Tail of linked list of functions to call on disconnects by clients.
111 struct NotifyList *disconnect_notify_list_tail;
114 * Function to call for access control.
116 GNUNET_CONNECTION_AccessCheck access;
119 * Closure for access.
124 * NULL-terminated array of sockets used to listen for new
127 struct GNUNET_NETWORK_Handle **listen_sockets;
130 * After how long should an idle connection time
133 struct GNUNET_TIME_Relative idle_timeout;
136 * Task scheduled to do the listening.
138 GNUNET_SCHEDULER_TaskIdentifier listen_task;
141 * Alternative function to create a MST instance.
143 GNUNET_SERVER_MstCreateCallback mst_create;
146 * Alternative function to destroy a MST instance.
148 GNUNET_SERVER_MstDestroyCallback mst_destroy;
151 * Alternative function to give data to a MST instance.
153 GNUNET_SERVER_MstReceiveCallback mst_receive;
156 * Closure for 'mst_'-callbacks.
161 * Do we ignore messages of types that we do not understand or do we
162 * require that a handler is found (and if not kill the connection)?
167 * Set to GNUNET_YES once we are in 'soft' shutdown where we wait for
168 * all non-monitor clients to disconnect before we call
169 * GNUNET_SERVER_destroy. See 'test_monitor_clients'. Set to
170 * GNUNET_SYSERR once the final destroy task has been scheduled
171 * (we cannot run it in the same task).
173 int in_soft_shutdown;
178 * Handle server returns for aborting transmission to a client.
180 struct GNUNET_SERVER_TransmitHandle
183 * Function to call to get the message.
185 GNUNET_CONNECTION_TransmitReadyNotify callback;
188 * Closure for 'callback'
193 * Active connection transmission handle.
195 struct GNUNET_CONNECTION_TransmitHandle *cth;
201 * @brief handle for a client of the server
203 struct GNUNET_SERVER_Client
207 * This is a doubly linked list.
209 struct GNUNET_SERVER_Client *next;
212 * This is a doubly linked list.
214 struct GNUNET_SERVER_Client *prev;
217 * Processing of incoming data.
222 * Server that this client belongs to.
224 struct GNUNET_SERVER_Handle *server;
227 * Client closure for callbacks.
229 struct GNUNET_CONNECTION_Handle *connection;
232 * ID of task used to restart processing.
234 GNUNET_SCHEDULER_TaskIdentifier restart_task;
237 * Task that warns about missing calls to 'GNUNET_SERVER_receive_done'.
239 GNUNET_SCHEDULER_TaskIdentifier warn_task;
242 * Time when the warn task was started.
244 struct GNUNET_TIME_Absolute warn_start;
247 * Last activity on this socket (used to time it out
248 * if reference_count == 0).
250 struct GNUNET_TIME_Absolute last_activity;
253 * Transmission handle we return for this client from
254 * GNUNET_SERVER_notify_transmit_ready.
256 struct GNUNET_SERVER_TransmitHandle th;
259 * After how long should an idle connection time
262 struct GNUNET_TIME_Relative idle_timeout;
265 * Number of external entities with a reference to
266 * this client object.
268 unsigned int reference_count;
271 * Was processing if incoming messages suspended while
272 * we were still processing data already received?
273 * This is a counter saying how often processing was
274 * suspended (once per handler invoked).
276 unsigned int suspended;
279 * Are we currently in the "process_client_buffer" function (and
280 * will hence restart the receive job on exit if suspended == 0 once
281 * we are done?). If this is set, then "receive_done" will
282 * essentially only decrement suspended; if this is not set, then
283 * "receive_done" may need to restart the receive process (either
284 * from the side-buffer or via select/recv).
286 int in_process_client_buffer;
289 * We're about to close down this client due to some serious
295 * Are we currently trying to receive? (YES if we are, NO if we are not,
296 * SYSERR if data is already available in MST).
301 * Finish pending write when disconnecting?
303 int finish_pending_write;
306 * Persist the file handle for this client no matter what happens,
307 * force the OS to close once the process actually dies. Should only
308 * be used in special cases!
313 * Is this client a 'monitor' client that should not be counted
314 * when deciding on destroying the server during soft shutdown?
315 * (see also GNUNET_SERVICE_start)
320 * Type of last message processed (for warn_no_receive_done).
327 * Scheduler says our listen socket is ready. Process it!
329 * @param cls handle to our server for which we are processing the listen
331 * @param tc reason why we are running right now
334 process_listen_socket (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
336 struct GNUNET_SERVER_Handle *server = cls;
337 struct GNUNET_CONNECTION_Handle *sock;
338 struct GNUNET_SERVER_Client *client;
339 struct GNUNET_NETWORK_FDSet *r;
342 server->listen_task = GNUNET_SCHEDULER_NO_TASK;
343 r = GNUNET_NETWORK_fdset_create ();
345 while (NULL != server->listen_sockets[i])
346 GNUNET_NETWORK_fdset_set (r, server->listen_sockets[i++]);
347 if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
349 /* ignore shutdown, someone else will take care of it! */
350 server->listen_task =
351 GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_HIGH,
352 GNUNET_TIME_UNIT_FOREVER_REL, r, NULL,
353 &process_listen_socket, server);
354 GNUNET_NETWORK_fdset_destroy (r);
358 while (NULL != server->listen_sockets[i])
360 if (GNUNET_NETWORK_fdset_isset (tc->read_ready, server->listen_sockets[i]))
363 GNUNET_CONNECTION_create_from_accept (server->access,
365 server->listen_sockets[i]);
368 LOG (GNUNET_ERROR_TYPE_DEBUG, "Server accepted incoming connection.\n");
369 client = GNUNET_SERVER_connect_socket (server, sock);
370 /* decrement reference count, we don't keep "client" alive */
371 GNUNET_SERVER_client_drop (client);
376 /* listen for more! */
377 server->listen_task =
378 GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_HIGH,
379 GNUNET_TIME_UNIT_FOREVER_REL, r, NULL,
380 &process_listen_socket, server);
381 GNUNET_NETWORK_fdset_destroy (r);
386 * Create and initialize a listen socket for the server.
388 * @param serverAddr address to listen on
389 * @param socklen length of address
390 * @return NULL on error, otherwise the listen socket
392 static struct GNUNET_NETWORK_Handle *
393 open_listen_socket (const struct sockaddr *serverAddr, socklen_t socklen)
395 const static int on = 1;
396 struct GNUNET_NETWORK_Handle *sock;
400 switch (serverAddr->sa_family)
403 port = ntohs (((const struct sockaddr_in *) serverAddr)->sin_port);
406 port = ntohs (((const struct sockaddr_in6 *) serverAddr)->sin6_port);
416 sock = GNUNET_NETWORK_socket_create (serverAddr->sa_family, SOCK_STREAM, 0);
419 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "socket");
425 if (GNUNET_NETWORK_socket_setsockopt
426 (sock, SOL_SOCKET, SO_REUSEADDR, &on, sizeof (on)) != GNUNET_OK)
427 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
430 if ((AF_INET6 == serverAddr->sa_family) &&
431 (GNUNET_NETWORK_socket_setsockopt
432 (sock, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof (on)) != GNUNET_OK))
433 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR | GNUNET_ERROR_TYPE_BULK,
437 /* bind the socket */
438 if (GNUNET_OK != GNUNET_NETWORK_socket_bind (sock, serverAddr, socklen))
441 if (EADDRINUSE != errno)
443 /* we don't log 'EADDRINUSE' here since an IPv4 bind may
444 * fail if we already took the port on IPv6; if both IPv4 and
445 * IPv6 binds fail, then our caller will log using the
446 * errno preserved in 'eno' */
447 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "bind");
449 LOG (GNUNET_ERROR_TYPE_ERROR, _("`%s' failed for port %d (%s).\n"),
451 (AF_INET == serverAddr->sa_family) ? "IPv4" : "IPv6");
457 LOG (GNUNET_ERROR_TYPE_WARNING,
458 _("`%s' failed for port %d (%s): address already in use\n"),
460 (AF_INET == serverAddr->sa_family) ? "IPv4" : "IPv6");
461 else if (AF_UNIX == serverAddr->sa_family)
462 LOG (GNUNET_ERROR_TYPE_WARNING,
463 _("`%s' failed for `%s': address already in use\n"), "bind",
464 ((const struct sockaddr_un *) serverAddr)->sun_path);
467 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (sock));
471 if (GNUNET_OK != GNUNET_NETWORK_socket_listen (sock, 5))
473 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "listen");
474 GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_close (sock));
479 LOG (GNUNET_ERROR_TYPE_DEBUG, "Server starts to listen on port %u.\n",
486 * Create a new server.
488 * @param access function for access control
489 * @param access_cls closure for access
490 * @param lsocks NULL-terminated array of listen sockets
491 * @param idle_timeout after how long should we timeout idle connections?
492 * @param require_found if YES, connections sending messages of unknown type
494 * @return handle for the new server, NULL on error
495 * (typically, "port" already in use)
497 struct GNUNET_SERVER_Handle *
498 GNUNET_SERVER_create_with_sockets (GNUNET_CONNECTION_AccessCheck access,
500 struct GNUNET_NETWORK_Handle **lsocks,
501 struct GNUNET_TIME_Relative idle_timeout,
504 struct GNUNET_SERVER_Handle *server;
505 struct GNUNET_NETWORK_FDSet *r;
508 server = GNUNET_malloc (sizeof (struct GNUNET_SERVER_Handle));
509 server->idle_timeout = idle_timeout;
510 server->listen_sockets = lsocks;
511 server->access = access;
512 server->access_cls = access_cls;
513 server->require_found = require_found;
516 r = GNUNET_NETWORK_fdset_create ();
518 while (NULL != server->listen_sockets[i])
519 GNUNET_NETWORK_fdset_set (r, server->listen_sockets[i++]);
520 server->listen_task =
521 GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_HIGH,
522 GNUNET_TIME_UNIT_FOREVER_REL, r, NULL,
523 &process_listen_socket, server);
524 GNUNET_NETWORK_fdset_destroy (r);
531 * Create a new server.
533 * @param access function for access control
534 * @param access_cls closure for access
535 * @param serverAddr address to listen on (including port), NULL terminated array
536 * @param socklen length of serverAddr
537 * @param idle_timeout after how long should we timeout idle connections?
538 * @param require_found if YES, connections sending messages of unknown type
540 * @return handle for the new server, NULL on error
541 * (typically, "port" already in use)
543 struct GNUNET_SERVER_Handle *
544 GNUNET_SERVER_create (GNUNET_CONNECTION_AccessCheck access, void *access_cls,
545 struct sockaddr *const *serverAddr,
546 const socklen_t * socklen,
547 struct GNUNET_TIME_Relative idle_timeout,
550 struct GNUNET_NETWORK_Handle **lsocks;
557 while (NULL != serverAddr[i])
561 lsocks = GNUNET_malloc (sizeof (struct GNUNET_NETWORK_Handle *) * (i + 1));
564 while (NULL != serverAddr[i])
568 if ( (socklen[k] == socklen[i]) &&
569 (0 == memcmp (serverAddr[k], serverAddr[i], socklen[i])) )
576 /* duplicate address, skip */
580 lsocks[j] = open_listen_socket (serverAddr[i], socklen[i]);
581 if (NULL != lsocks[j])
588 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "bind");
589 GNUNET_free (lsocks);
597 return GNUNET_SERVER_create_with_sockets (access, access_cls, lsocks,
598 idle_timeout, require_found);
603 * Set the 'monitor' flag on this client. Clients which have been
604 * marked as 'monitors' won't prevent the server from shutting down
605 * once 'GNUNET_SERVER_stop_listening' has been invoked. The idea is
606 * that for "normal" clients we likely want to allow them to process
607 * their requests; however, monitor-clients are likely to 'never'
608 * disconnect during shutdown and thus will not be considered when
609 * determining if the server should continue to exist after
610 * 'GNUNET_SERVER_destroy' has been called.
612 * @param client the client to set the 'monitor' flag on
615 GNUNET_SERVER_client_mark_monitor (struct GNUNET_SERVER_Client *client)
617 client->is_monitor = GNUNET_YES;
622 * Helper function for 'test_monitor_clients' to trigger
623 * 'GNUNET_SERVER_destroy' after the stack has unwound.
625 * @param cls the 'struct GNUNET_SERVER_Handle' to destroy
629 do_destroy (void *cls,
630 const struct GNUNET_SCHEDULER_TaskContext *tc)
632 struct GNUNET_SERVER_Handle *server = cls;
633 GNUNET_SERVER_destroy (server);
638 * Check if only 'monitor' clients are left. If so, destroy the
641 * @param server server to test for full shutdown
644 test_monitor_clients (struct GNUNET_SERVER_Handle *server)
646 struct GNUNET_SERVER_Client *client;
648 if (GNUNET_YES != server->in_soft_shutdown)
650 for (client = server->clients_head; NULL != client; client = client->next)
651 if (GNUNET_NO == client->is_monitor)
652 return; /* not done yet */
653 server->in_soft_shutdown = GNUNET_SYSERR;
654 GNUNET_SCHEDULER_add_continuation (&do_destroy, server,
655 GNUNET_SCHEDULER_REASON_PREREQ_DONE);
660 * Stop the listen socket and get ready to shutdown the server
661 * once only 'monitor' clients are left.
663 * @param server server to stop listening on
666 GNUNET_SERVER_stop_listening (struct GNUNET_SERVER_Handle *server)
670 LOG (GNUNET_ERROR_TYPE_DEBUG, "Server in soft shutdown\n");
671 if (GNUNET_SCHEDULER_NO_TASK != server->listen_task)
673 GNUNET_SCHEDULER_cancel (server->listen_task);
674 server->listen_task = GNUNET_SCHEDULER_NO_TASK;
676 if (NULL != server->listen_sockets)
679 while (NULL != server->listen_sockets[i])
680 GNUNET_break (GNUNET_OK ==
681 GNUNET_NETWORK_socket_close (server->listen_sockets[i++]));
682 GNUNET_free (server->listen_sockets);
683 server->listen_sockets = NULL;
685 if (GNUNET_NO == server->in_soft_shutdown)
686 server->in_soft_shutdown = GNUNET_YES;
687 test_monitor_clients (server);
692 * Free resources held by this server.
694 * @param server server to destroy
697 GNUNET_SERVER_destroy (struct GNUNET_SERVER_Handle *server)
699 struct HandlerList *hpos;
700 struct NotifyList *npos;
703 LOG (GNUNET_ERROR_TYPE_DEBUG, "Server shutting down.\n");
704 if (GNUNET_SCHEDULER_NO_TASK != server->listen_task)
706 GNUNET_SCHEDULER_cancel (server->listen_task);
707 server->listen_task = GNUNET_SCHEDULER_NO_TASK;
709 if (NULL != server->listen_sockets)
712 while (NULL != server->listen_sockets[i])
713 GNUNET_break (GNUNET_OK ==
714 GNUNET_NETWORK_socket_close (server->listen_sockets[i++]));
715 GNUNET_free (server->listen_sockets);
716 server->listen_sockets = NULL;
718 while (NULL != server->clients_head)
719 GNUNET_SERVER_client_disconnect (server->clients_head);
720 while (NULL != (hpos = server->handlers))
722 server->handlers = hpos->next;
725 while (NULL != (npos = server->disconnect_notify_list_head))
727 npos->callback (npos->callback_cls, NULL);
728 GNUNET_CONTAINER_DLL_remove (server->disconnect_notify_list_head,
729 server->disconnect_notify_list_tail,
733 GNUNET_free (server);
738 * Add additional handlers to an existing server.
740 * @param server the server to add handlers to
741 * @param handlers array of message handlers for
742 * incoming messages; the last entry must
743 * have "NULL" for the "callback"; multiple
744 * entries for the same type are allowed,
745 * they will be called in order of occurence.
746 * These handlers can be removed later;
747 * the handlers array must exist until removed
748 * (or server is destroyed).
751 GNUNET_SERVER_add_handlers (struct GNUNET_SERVER_Handle *server,
752 const struct GNUNET_SERVER_MessageHandler *handlers)
754 struct HandlerList *p;
756 p = GNUNET_malloc (sizeof (struct HandlerList));
757 p->handlers = handlers;
758 p->next = server->handlers;
759 server->handlers = p;
764 * Change functions used by the server to tokenize the message stream.
765 * (very rarely used).
767 * @param server server to modify
768 * @param create new tokenizer initialization function
769 * @param destroy new tokenizer destruction function
770 * @param receive new tokenizer receive function
771 * @param cls closure for 'create', 'receive', 'destroy'
774 GNUNET_SERVER_set_callbacks (struct GNUNET_SERVER_Handle *server,
775 GNUNET_SERVER_MstCreateCallback create,
776 GNUNET_SERVER_MstDestroyCallback destroy,
777 GNUNET_SERVER_MstReceiveCallback receive,
780 server->mst_create = create;
781 server->mst_destroy = destroy;
782 server->mst_receive = receive;
783 server->mst_cls = cls;
788 * Task run to warn about missing calls to 'GNUNET_SERVER_receive_done'.
790 * @param cls our 'struct GNUNET_SERVER_Client*' to process more requests from
791 * @param tc scheduler context (unused)
794 warn_no_receive_done (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
796 struct GNUNET_SERVER_Client *client = cls;
799 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES,
800 &warn_no_receive_done, client);
801 if (0 == (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
802 LOG (GNUNET_ERROR_TYPE_WARNING,
804 ("Processing code for message of type %u did not call GNUNET_SERVER_receive_done after %llums\n"),
805 (unsigned int) client->warn_type,
807 GNUNET_TIME_absolute_get_duration (client->warn_start).rel_value);
812 * Disable the warning the server issues if a message is not acknowledged
813 * in a timely fashion. Use this call if a client is intentionally delayed
814 * for a while. Only applies to the current message.
816 * @param client client for which to disable the warning
819 GNUNET_SERVER_disable_receive_done_warning (struct GNUNET_SERVER_Client *client)
821 if (GNUNET_SCHEDULER_NO_TASK != client->warn_task)
823 GNUNET_SCHEDULER_cancel (client->warn_task);
824 client->warn_task = GNUNET_SCHEDULER_NO_TASK;
830 * Inject a message into the server, pretend it came
831 * from the specified client. Delivery of the message
832 * will happen instantly (if a handler is installed;
833 * otherwise the call does nothing).
835 * @param server the server receiving the message
836 * @param sender the "pretended" sender of the message
838 * @param message message to transmit
839 * @return GNUNET_OK if the message was OK and the
840 * connection can stay open
841 * GNUNET_SYSERR if the connection to the
842 * client should be shut down
845 GNUNET_SERVER_inject (struct GNUNET_SERVER_Handle *server,
846 struct GNUNET_SERVER_Client *sender,
847 const struct GNUNET_MessageHeader *message)
849 struct HandlerList *pos;
850 const struct GNUNET_SERVER_MessageHandler *mh;
856 type = ntohs (message->type);
857 size = ntohs (message->size);
858 LOG (GNUNET_ERROR_TYPE_DEBUG,
859 "Server schedules transmission of %u-byte message of type %u to client.\n",
862 for (pos = server->handlers; NULL != pos; pos = pos->next)
865 while (pos->handlers[i].callback != NULL)
867 mh = &pos->handlers[i];
868 if ((mh->type == type) || (mh->type == GNUNET_MESSAGE_TYPE_ALL))
870 if ((0 != mh->expected_size) && (mh->expected_size != size))
872 #if GNUNET8_NETWORK_IS_DEAD
873 LOG (GNUNET_ERROR_TYPE_WARNING,
874 "Expected %u bytes for message of type %u, got %u\n",
875 mh->expected_size, mh->type, size);
878 return GNUNET_SYSERR;
882 if (0 == sender->suspended)
884 sender->warn_start = GNUNET_TIME_absolute_get ();
886 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES,
887 &warn_no_receive_done, sender);
888 sender->warn_type = type;
892 mh->callback (mh->callback_cls, sender, message);
898 if (GNUNET_NO == found)
900 LOG (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
901 "Received message of unknown type %d\n", type);
902 if (GNUNET_YES == server->require_found)
903 return GNUNET_SYSERR;
910 * We are receiving an incoming message. Process it.
912 * @param cls our closure (handle for the client)
913 * @param buf buffer with data received from network
914 * @param available number of bytes available in buf
915 * @param addr address of the sender
916 * @param addrlen length of addr
917 * @param errCode code indicating errors receiving, 0 for success
920 process_incoming (void *cls, const void *buf, size_t available,
921 const struct sockaddr *addr, socklen_t addrlen, int errCode);
925 * Process messages from the client's message tokenizer until either
926 * the tokenizer is empty (and then schedule receiving more), or
927 * until some handler is not immediately done (then wait for restart_processing)
930 * @param client the client to process, RC must have already been increased
931 * using GNUNET_SERVER_client_keep and will be decreased by one in this
933 * @param ret GNUNET_NO to start processing from the buffer,
934 * GNUNET_OK if the mst buffer is drained and we should instantly go back to receiving
935 * GNUNET_SYSERR if we should instantly abort due to error in a previous step
938 process_mst (struct GNUNET_SERVER_Client *client, int ret)
940 while ((GNUNET_SYSERR != ret) && (NULL != client->server) &&
941 (GNUNET_YES != client->shutdown_now) && (0 == client->suspended))
943 if (GNUNET_OK == ret)
945 LOG (GNUNET_ERROR_TYPE_DEBUG,
946 "Server re-enters receive loop, timeout: %llu.\n",
947 client->idle_timeout.rel_value);
948 client->receive_pending = GNUNET_YES;
949 GNUNET_CONNECTION_receive (client->connection,
950 GNUNET_SERVER_MAX_MESSAGE_SIZE - 1,
951 client->idle_timeout, &process_incoming,
955 LOG (GNUNET_ERROR_TYPE_DEBUG,
956 "Server processes additional messages instantly.\n");
957 if (NULL != client->server->mst_receive)
959 client->server->mst_receive (client->server->mst_cls, client->mst,
960 client, NULL, 0, GNUNET_NO, GNUNET_YES);
963 GNUNET_SERVER_mst_receive (client->mst, client, NULL, 0, GNUNET_NO,
966 LOG (GNUNET_ERROR_TYPE_DEBUG,
967 "Server leaves instant processing loop: ret = %d, server = %p, shutdown = %d, suspended = %u\n",
968 ret, client->server, client->shutdown_now, client->suspended);
969 if (GNUNET_NO == ret)
971 LOG (GNUNET_ERROR_TYPE_DEBUG,
972 "Server has more data pending but is suspended.\n");
973 client->receive_pending = GNUNET_SYSERR; /* data pending */
975 if ((GNUNET_SYSERR == ret) || (GNUNET_YES == client->shutdown_now))
976 GNUNET_SERVER_client_disconnect (client);
981 * We are receiving an incoming message. Process it.
983 * @param cls our closure (handle for the client)
984 * @param buf buffer with data received from network
985 * @param available number of bytes available in buf
986 * @param addr address of the sender
987 * @param addrlen length of addr
988 * @param errCode code indicating errors receiving, 0 for success
991 process_incoming (void *cls, const void *buf, size_t available,
992 const struct sockaddr *addr, socklen_t addrlen, int errCode)
994 struct GNUNET_SERVER_Client *client = cls;
995 struct GNUNET_SERVER_Handle *server = client->server;
996 struct GNUNET_TIME_Absolute end;
997 struct GNUNET_TIME_Absolute now;
1000 GNUNET_assert (GNUNET_YES == client->receive_pending);
1001 client->receive_pending = GNUNET_NO;
1002 now = GNUNET_TIME_absolute_get ();
1003 end = GNUNET_TIME_absolute_add (client->last_activity, client->idle_timeout);
1005 if ((NULL == buf) && (0 == available) && (NULL == addr) && (0 == errCode) &&
1006 (GNUNET_YES != client->shutdown_now) && (NULL != server) &&
1007 (GNUNET_YES == GNUNET_CONNECTION_check (client->connection)) &&
1008 (end.abs_value > now.abs_value))
1010 /* wait longer, timeout changed (i.e. due to us sending) */
1011 LOG (GNUNET_ERROR_TYPE_DEBUG,
1012 "Receive time out, but no disconnect due to sending (%p)\n",
1013 GNUNET_a2s (addr, addrlen));
1014 client->receive_pending = GNUNET_YES;
1015 GNUNET_CONNECTION_receive (client->connection,
1016 GNUNET_SERVER_MAX_MESSAGE_SIZE - 1,
1017 GNUNET_TIME_absolute_get_remaining (end),
1018 &process_incoming, client);
1021 if ((NULL == buf) || (0 == available) || (0 != errCode) || (NULL == server) ||
1022 (GNUNET_YES == client->shutdown_now) ||
1023 (GNUNET_YES != GNUNET_CONNECTION_check (client->connection)))
1025 /* other side closed connection, error connecting, etc. */
1026 GNUNET_SERVER_client_disconnect (client);
1029 LOG (GNUNET_ERROR_TYPE_DEBUG, "Server receives %u bytes from `%s'.\n",
1030 (unsigned int) available, GNUNET_a2s (addr, addrlen));
1031 GNUNET_SERVER_client_keep (client);
1032 client->last_activity = now;
1034 if (NULL != server->mst_receive)
1036 client->server->mst_receive (client->server->mst_cls, client->mst,
1037 client, buf, available, GNUNET_NO, GNUNET_YES);
1040 GNUNET_SERVER_mst_receive (client->mst, client, buf, available, GNUNET_NO,
1042 process_mst (client, ret);
1043 GNUNET_SERVER_client_drop (client);
1048 * Task run to start again receiving from the network
1049 * and process requests.
1051 * @param cls our 'struct GNUNET_SERVER_Client*' to process more requests from
1052 * @param tc scheduler context (unused)
1055 restart_processing (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1057 struct GNUNET_SERVER_Client *client = cls;
1059 GNUNET_assert (GNUNET_YES != client->shutdown_now);
1060 client->restart_task = GNUNET_SCHEDULER_NO_TASK;
1061 if (GNUNET_NO == client->receive_pending)
1063 LOG (GNUNET_ERROR_TYPE_DEBUG, "Server begins to read again from client.\n");
1064 client->receive_pending = GNUNET_YES;
1065 GNUNET_CONNECTION_receive (client->connection,
1066 GNUNET_SERVER_MAX_MESSAGE_SIZE - 1,
1067 client->idle_timeout, &process_incoming, client);
1070 LOG (GNUNET_ERROR_TYPE_DEBUG,
1071 "Server continues processing messages still in the buffer.\n");
1072 GNUNET_SERVER_client_keep (client);
1073 client->receive_pending = GNUNET_NO;
1074 process_mst (client, GNUNET_NO);
1075 GNUNET_SERVER_client_drop (client);
1080 * This function is called whenever our inbound message tokenizer has
1081 * received a complete message.
1083 * @param cls closure (struct GNUNET_SERVER_Handle)
1084 * @param client identification of the client (struct GNUNET_SERVER_Client*)
1085 * @param message the actual message
1088 client_message_tokenizer_callback (void *cls, void *client,
1089 const struct GNUNET_MessageHeader *message)
1091 struct GNUNET_SERVER_Handle *server = cls;
1092 struct GNUNET_SERVER_Client *sender = client;
1095 LOG (GNUNET_ERROR_TYPE_DEBUG,
1096 "Tokenizer gives server message of type %u from client\n",
1097 ntohs (message->type));
1098 sender->in_process_client_buffer = GNUNET_YES;
1099 ret = GNUNET_SERVER_inject (server, sender, message);
1100 sender->in_process_client_buffer = GNUNET_NO;
1101 if (GNUNET_OK != ret)
1102 GNUNET_SERVER_client_disconnect (sender);
1107 * Add a TCP socket-based connection to the set of handles managed by
1108 * this server. Use this function for outgoing (P2P) connections that
1109 * we initiated (and where this server should process incoming
1112 * @param server the server to use
1113 * @param connection the connection to manage (client must
1114 * stop using this connection from now on)
1115 * @return the client handle (client should call
1116 * "client_drop" on the return value eventually)
1118 struct GNUNET_SERVER_Client *
1119 GNUNET_SERVER_connect_socket (struct GNUNET_SERVER_Handle *server,
1120 struct GNUNET_CONNECTION_Handle *connection)
1122 struct GNUNET_SERVER_Client *client;
1124 client = GNUNET_malloc (sizeof (struct GNUNET_SERVER_Client));
1125 client->connection = connection;
1126 client->reference_count = 1;
1127 client->server = server;
1128 client->last_activity = GNUNET_TIME_absolute_get ();
1129 client->idle_timeout = server->idle_timeout;
1130 GNUNET_CONTAINER_DLL_insert (server->clients_head,
1131 server->clients_tail,
1133 if (NULL != server->mst_create)
1135 server->mst_create (server->mst_cls, client);
1138 GNUNET_SERVER_mst_create (&client_message_tokenizer_callback, server);
1139 client->receive_pending = GNUNET_YES;
1140 GNUNET_CONNECTION_receive (client->connection,
1141 GNUNET_SERVER_MAX_MESSAGE_SIZE - 1,
1142 client->idle_timeout, &process_incoming, client);
1148 * Change the timeout for a particular client. Decreasing the timeout
1149 * may not go into effect immediately (only after the previous timeout
1150 * times out or activity happens on the socket).
1152 * @param client the client to update
1153 * @param timeout new timeout for activities on the socket
1156 GNUNET_SERVER_client_set_timeout (struct GNUNET_SERVER_Client *client,
1157 struct GNUNET_TIME_Relative timeout)
1159 client->idle_timeout = timeout;
1164 * Notify the server that the given client handle should
1165 * be kept (keeps the connection up if possible, increments
1166 * the internal reference counter).
1168 * @param client the client to keep
1171 GNUNET_SERVER_client_keep (struct GNUNET_SERVER_Client *client)
1173 client->reference_count++;
1178 * Notify the server that the given client handle is no
1179 * longer required. Decrements the reference counter. If
1180 * that counter reaches zero an inactive connection maybe
1183 * @param client the client to drop
1186 GNUNET_SERVER_client_drop (struct GNUNET_SERVER_Client *client)
1188 GNUNET_assert (client->reference_count > 0);
1189 client->reference_count--;
1190 if ((GNUNET_YES == client->shutdown_now) && (0 == client->reference_count))
1191 GNUNET_SERVER_client_disconnect (client);
1196 * Obtain the network address of the other party.
1198 * @param client the client to get the address for
1199 * @param addr where to store the address
1200 * @param addrlen where to store the length of the address
1201 * @return GNUNET_OK on success
1204 GNUNET_SERVER_client_get_address (struct GNUNET_SERVER_Client *client,
1205 void **addr, size_t * addrlen)
1207 return GNUNET_CONNECTION_get_address (client->connection, addr, addrlen);
1212 * Ask the server to notify us whenever a client disconnects.
1213 * This function is called whenever the actual network connection
1214 * is closed; the reference count may be zero or larger than zero
1217 * @param server the server manageing the clients
1218 * @param callback function to call on disconnect
1219 * @param callback_cls closure for callback
1222 GNUNET_SERVER_disconnect_notify (struct GNUNET_SERVER_Handle *server,
1223 GNUNET_SERVER_DisconnectCallback callback,
1226 struct NotifyList *n;
1228 n = GNUNET_malloc (sizeof (struct NotifyList));
1229 n->callback = callback;
1230 n->callback_cls = callback_cls;
1231 GNUNET_CONTAINER_DLL_insert (server->disconnect_notify_list_head,
1232 server->disconnect_notify_list_tail,
1238 * Ask the server to stop notifying us whenever a client disconnects.
1240 * @param server the server manageing the clients
1241 * @param callback function to call on disconnect
1242 * @param callback_cls closure for callback
1245 GNUNET_SERVER_disconnect_notify_cancel (struct GNUNET_SERVER_Handle *server,
1246 GNUNET_SERVER_DisconnectCallback
1247 callback, void *callback_cls)
1249 struct NotifyList *pos;
1251 for (pos = server->disconnect_notify_list_head; NULL != pos; pos = pos->next)
1252 if ((pos->callback == callback) && (pos->callback_cls == callback_cls))
1259 GNUNET_CONTAINER_DLL_remove (server->disconnect_notify_list_head,
1260 server->disconnect_notify_list_tail,
1267 * Destroy the connection that is passed in via 'cls'. Used
1268 * as calling 'GNUNET_CONNECTION_destroy' from within a function
1269 * that was itself called from within 'process_notify' of
1270 * 'connection.c' is not allowed (see #2329).
1272 * @param cls connection to destroy
1273 * @param tc scheduler context (unused)
1276 destroy_connection (void *cls,
1277 const struct GNUNET_SCHEDULER_TaskContext *tc)
1279 struct GNUNET_CONNECTION_Handle *connection = cls;
1281 GNUNET_CONNECTION_destroy (connection);
1286 * Ask the server to disconnect from the given client.
1287 * This is the same as returning GNUNET_SYSERR from a message
1288 * handler, except that it allows dropping of a client even
1289 * when not handling a message from that client.
1291 * @param client the client to disconnect from
1294 GNUNET_SERVER_client_disconnect (struct GNUNET_SERVER_Client *client)
1296 struct GNUNET_SERVER_Handle *server = client->server;
1297 struct GNUNET_SERVER_Client *pos;
1298 struct NotifyList *n;
1300 LOG (GNUNET_ERROR_TYPE_DEBUG,
1301 "Client is being disconnected from the server.\n");
1302 if (GNUNET_SCHEDULER_NO_TASK != client->restart_task)
1304 GNUNET_SCHEDULER_cancel (client->restart_task);
1305 client->restart_task = GNUNET_SCHEDULER_NO_TASK;
1307 if (GNUNET_SCHEDULER_NO_TASK != client->warn_task)
1309 GNUNET_SCHEDULER_cancel (client->warn_task);
1310 client->warn_task = GNUNET_SCHEDULER_NO_TASK;
1312 if (GNUNET_YES == client->receive_pending)
1314 GNUNET_CONNECTION_receive_cancel (client->connection);
1315 client->receive_pending = GNUNET_NO;
1318 client->reference_count++; /* make sure nobody else clean up client... */
1319 if ( (GNUNET_YES != client->shutdown_now) &&
1322 client->shutdown_now = GNUNET_YES;
1323 pos = server->clients_head;
1324 while ((NULL != pos) && (pos != client))
1326 GNUNET_assert (NULL != pos);
1327 GNUNET_CONTAINER_DLL_remove (server->clients_head,
1328 server->clients_tail,
1330 if (GNUNET_SCHEDULER_NO_TASK != client->restart_task)
1332 GNUNET_SCHEDULER_cancel (client->restart_task);
1333 client->restart_task = GNUNET_SCHEDULER_NO_TASK;
1335 if (GNUNET_SCHEDULER_NO_TASK != client->warn_task)
1337 GNUNET_SCHEDULER_cancel (client->warn_task);
1338 client->warn_task = GNUNET_SCHEDULER_NO_TASK;
1340 for (n = server->disconnect_notify_list_head; NULL != n; n = n->next)
1341 n->callback (n->callback_cls, client);
1342 if (NULL != server->mst_destroy)
1343 server->mst_destroy (server->mst_cls, client->mst);
1345 GNUNET_SERVER_mst_destroy (client->mst);
1348 client->reference_count--;
1349 if (client->reference_count > 0)
1351 LOG (GNUNET_ERROR_TYPE_DEBUG,
1352 "RC still positive, not destroying everything.\n");
1353 client->server = NULL;
1356 if (GNUNET_YES == client->in_process_client_buffer)
1358 LOG (GNUNET_ERROR_TYPE_DEBUG,
1359 "Still processing inputs, not destroying everything.\n");
1362 if (GNUNET_YES == client->persist)
1363 GNUNET_CONNECTION_persist_ (client->connection);
1364 if (NULL != client->th.cth)
1365 GNUNET_SERVER_notify_transmit_ready_cancel (&client->th);
1366 (void) GNUNET_SCHEDULER_add_now (&destroy_connection,
1367 client->connection);
1368 GNUNET_free (client);
1369 /* we might be in soft-shutdown, test if we're done */
1371 test_monitor_clients (server);
1376 * Disable the "CORK" feature for communication with the given client,
1377 * forcing the OS to immediately flush the buffer on transmission
1378 * instead of potentially buffering multiple messages.
1380 * @param client handle to the client
1381 * @return GNUNET_OK on success
1384 GNUNET_SERVER_client_disable_corking (struct GNUNET_SERVER_Client *client)
1386 return GNUNET_CONNECTION_disable_corking (client->connection);
1391 * Wrapper for transmission notification that calls the original
1392 * callback and update the last activity time for our connection.
1394 * @param cls the 'struct GNUNET_SERVER_Client'
1395 * @param size number of bytes we can transmit
1396 * @param buf where to copy the message
1397 * @return number of bytes actually transmitted
1400 transmit_ready_callback_wrapper (void *cls, size_t size, void *buf)
1402 struct GNUNET_SERVER_Client *client = cls;
1403 GNUNET_CONNECTION_TransmitReadyNotify callback;
1405 client->th.cth = NULL;
1406 callback = client->th.callback;
1407 client->th.callback = NULL;
1408 client->last_activity = GNUNET_TIME_absolute_get ();
1409 return callback (client->th.callback_cls, size, buf);
1414 * Notify us when the server has enough space to transmit
1415 * a message of the given size to the given client.
1417 * @param client client to transmit message to
1418 * @param size requested amount of buffer space
1419 * @param timeout after how long should we give up (and call
1420 * notify with buf NULL and size 0)?
1421 * @param callback function to call when space is available
1422 * @param callback_cls closure for callback
1423 * @return non-NULL if the notify callback was queued; can be used
1424 * to cancel the request using
1425 * GNUNET_SERVER_notify_transmit_ready_cancel.
1426 * NULL if we are already going to notify someone else (busy)
1428 struct GNUNET_SERVER_TransmitHandle *
1429 GNUNET_SERVER_notify_transmit_ready (struct GNUNET_SERVER_Client *client,
1431 struct GNUNET_TIME_Relative timeout,
1432 GNUNET_CONNECTION_TransmitReadyNotify
1433 callback, void *callback_cls)
1435 if (NULL != client->th.callback)
1437 client->th.callback_cls = callback_cls;
1438 client->th.callback = callback;
1439 client->th.cth = GNUNET_CONNECTION_notify_transmit_ready (client->connection, size,
1441 &transmit_ready_callback_wrapper,
1448 * Abort transmission request.
1450 * @param th request to abort
1453 GNUNET_SERVER_notify_transmit_ready_cancel (struct GNUNET_SERVER_TransmitHandle *th)
1455 GNUNET_CONNECTION_notify_transmit_ready_cancel (th->cth);
1457 th->callback = NULL;
1462 * Set the persistent flag on this client, used to setup client connection
1463 * to only be killed when the service it's connected to is actually dead.
1465 * @param client the client to set the persistent flag on
1468 GNUNET_SERVER_client_persist_ (struct GNUNET_SERVER_Client *client)
1470 client->persist = GNUNET_YES;
1475 * Resume receiving from this client, we are done processing the
1476 * current request. This function must be called from within each
1477 * GNUNET_SERVER_MessageCallback (or its respective continuations).
1479 * @param client client we were processing a message of
1480 * @param success GNUNET_OK to keep the connection open and
1481 * continue to receive
1482 * GNUNET_NO to close the connection (normal behavior)
1483 * GNUNET_SYSERR to close the connection (signal
1487 GNUNET_SERVER_receive_done (struct GNUNET_SERVER_Client *client, int success)
1491 GNUNET_assert (client->suspended > 0);
1492 client->suspended--;
1493 if (GNUNET_OK != success)
1495 LOG (GNUNET_ERROR_TYPE_DEBUG,
1496 "GNUNET_SERVER_receive_done called with failure indication\n");
1497 if ( (client->reference_count > 0) || (client->suspended > 0) )
1498 client->shutdown_now = GNUNET_YES;
1500 GNUNET_SERVER_client_disconnect (client);
1503 if (client->suspended > 0)
1505 LOG (GNUNET_ERROR_TYPE_DEBUG,
1506 "GNUNET_SERVER_receive_done called, but more clients pending\n");
1509 if (GNUNET_SCHEDULER_NO_TASK != client->warn_task)
1511 GNUNET_SCHEDULER_cancel (client->warn_task);
1512 client->warn_task = GNUNET_SCHEDULER_NO_TASK;
1514 if (GNUNET_YES == client->in_process_client_buffer)
1516 LOG (GNUNET_ERROR_TYPE_DEBUG,
1517 "GNUNET_SERVER_receive_done called while still in processing loop\n");
1520 if ((NULL == client->server) || (GNUNET_YES == client->shutdown_now))
1522 GNUNET_SERVER_client_disconnect (client);
1525 LOG (GNUNET_ERROR_TYPE_DEBUG,
1526 "GNUNET_SERVER_receive_done causes restart in reading from the socket\n");
1527 GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == client->restart_task);
1528 client->restart_task = GNUNET_SCHEDULER_add_now (&restart_processing, client);
1532 /* end of server.c */