2 This file is part of GNUnet.
3 (C) 2010-2014 Christian Grothoff (and other contributing authors)
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6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
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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.
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17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file transport/gnunet-service-transport_clients.c
23 * @brief plugin management API
24 * @author Christian Grothoff
27 #include "gnunet-service-transport_blacklist.h"
28 #include "gnunet-service-transport_clients.h"
29 #include "gnunet-service-transport_hello.h"
30 #include "gnunet-service-transport_neighbours.h"
31 #include "gnunet-service-transport_plugins.h"
32 #include "gnunet-service-transport_validation.h"
33 #include "gnunet-service-transport_manipulation.h"
34 #include "gnunet-service-transport.h"
35 #include "transport.h"
39 * How many messages can we have pending for a given client process
40 * before we start to drop incoming messages? We typically should
41 * have only one client and so this would be the primary buffer for
42 * messages, so the number should be chosen rather generously.
44 * The expectation here is that most of the time the queue is large
45 * enough so that a drop is virtually never required. Note that
46 * this value must be about as large as 'TOTAL_MSGS' in the
47 * 'test_transport_api_reliability.c', otherwise that testcase may
50 #define MAX_PENDING (128 * 1024)
54 * Linked list of messages to be transmitted to the client. Each
55 * entry is followed by the actual message.
57 struct ClientMessageQueueEntry
60 * This is a doubly-linked list.
62 struct ClientMessageQueueEntry *next;
65 * This is a doubly-linked list.
67 struct ClientMessageQueueEntry *prev;
72 * Client connected to the transport service.
74 struct TransportClient
78 * This is a doubly-linked list.
80 struct TransportClient *next;
83 * This is a doubly-linked list.
85 struct TransportClient *prev;
88 * Handle to the client.
90 struct GNUNET_SERVER_Client *client;
93 * Linked list of messages yet to be transmitted to
96 struct ClientMessageQueueEntry *message_queue_head;
99 * Tail of linked list of messages yet to be transmitted to the
102 struct ClientMessageQueueEntry *message_queue_tail;
105 * Current transmit request handle.
107 struct GNUNET_SERVER_TransmitHandle *th;
110 * Length of the list of messages pending for this client.
112 unsigned int message_count;
115 * Is this client interested in payload messages?
122 * Context for address to string operations
124 struct AddressToStringContext
127 * This is a doubly-linked list.
129 struct AddressToStringContext *next;
132 * This is a doubly-linked list.
134 struct AddressToStringContext *prev;
137 * Transmission context
139 struct GNUNET_SERVER_TransmitContext* tc;
144 * Client monitoring changes of active addresses or validations
145 * of our neighbours. Which type is being monitored depends on the
146 * DLL this struct is in.
148 struct MonitoringClient
151 * This is a doubly-linked list.
153 struct MonitoringClient *next;
156 * This is a doubly-linked list.
158 struct MonitoringClient *prev;
161 * Handle to the client.
163 struct GNUNET_SERVER_Client *client;
166 * Peer identity to monitor the addresses of.
167 * Zero to monitor all neighrours.
169 struct GNUNET_PeerIdentity peer;
175 * Head of linked list of all clients to this service.
177 static struct TransportClient *clients_head;
180 * Tail of linked list of all clients to this service.
182 static struct TransportClient *clients_tail;
185 * Head of linked list of all pending address iterations
187 static struct AddressToStringContext *a2s_head;
190 * Tail of linked list of all pending address iterations
192 static struct AddressToStringContext *a2s_tail;
195 * Head of linked list of monitoring clients.
197 static struct MonitoringClient *peer_monitoring_clients_head;
200 * Tail of linked list of monitoring clients.
202 static struct MonitoringClient *peer_monitoring_clients_tail;
205 * Head of linked list of validation monitoring clients.
207 static struct MonitoringClient *val_monitoring_clients_head;
210 * Tail of linked list of validation monitoring clients.
212 static struct MonitoringClient *val_monitoring_clients_tail;
215 * Notification context, to send updates on changes to active addresses
218 static struct GNUNET_SERVER_NotificationContext *peer_nc;
221 * Notification context, to send updates on changes to active addresses
224 static struct GNUNET_SERVER_NotificationContext *val_nc;
227 * Notification context, to send updates on changes to active plugin
230 static struct GNUNET_SERVER_NotificationContext *plugin_nc;
233 * Plugin monitoring client we are currently syncing, NULL if all
234 * monitoring clients are in sync.
236 static struct GNUNET_SERVER_Client *sync_client;
239 * Peer identity that is all zeros, used as a way to indicate
240 * "all peers". Used for comparissons.
242 static struct GNUNET_PeerIdentity all_zeros;
246 * Find the internal handle associated with the given client handle.
248 * @param client server's client handle to look up
249 * @return internal client handle
251 static struct TransportClient *
252 lookup_client (struct GNUNET_SERVER_Client *client)
254 return GNUNET_SERVER_client_get_user_context (client,
255 struct TransportClient);
260 * Create the internal handle for the given server client handle.
262 * @param client server's client handle to create our internal handle for
263 * @return fresh internal client handle
265 static struct TransportClient *
266 setup_client (struct GNUNET_SERVER_Client *client)
268 struct TransportClient *tc;
270 GNUNET_assert (NULL == lookup_client (client));
271 tc = GNUNET_new (struct TransportClient);
273 GNUNET_SERVER_client_set_user_context (client, tc);
274 GNUNET_CONTAINER_DLL_insert (clients_head,
277 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
278 "Client %p connected\n",
285 * Find the handle to the monitoring client associated with the given
288 * @param head the head of the client queue to look in
289 * @param client server's client handle to look up
290 * @return handle to the monitoring client
292 static struct MonitoringClient *
293 lookup_monitoring_client (struct MonitoringClient *head,
294 struct GNUNET_SERVER_Client *client)
296 struct MonitoringClient *mc;
298 for (mc = head; NULL != mc; mc = mc->next)
299 if (mc->client == client)
306 * Setup a new monitoring client using the given server client handle and
309 * @param client server's client handle to create our internal handle for
310 * @param peer identity of the peer to monitor the addresses of,
311 * zero to monitor all neighrours.
312 * @return handle to the new monitoring client
314 static struct MonitoringClient *
315 setup_peer_monitoring_client (struct GNUNET_SERVER_Client *client,
316 const struct GNUNET_PeerIdentity *peer)
318 struct MonitoringClient *mc;
320 GNUNET_assert (NULL ==
321 lookup_monitoring_client (peer_monitoring_clients_head,
323 mc = GNUNET_new (struct MonitoringClient);
326 GNUNET_CONTAINER_DLL_insert (peer_monitoring_clients_head,
327 peer_monitoring_clients_tail,
329 GNUNET_SERVER_client_mark_monitor (client);
330 GNUNET_SERVER_notification_context_add (peer_nc,
332 if (0 != memcmp (peer,
334 sizeof (struct GNUNET_PeerIdentity)))
335 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
336 "Client %p started monitoring of the peer `%s'\n",
340 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
341 "Client %p started monitoring all peers\n",
348 * Setup a new monitoring client using the given server client handle and
351 * @param client server's client handle to create our internal handle for
352 * @param peer identity of the peer to monitor the addresses of,
353 * zero to monitor all neighrours.
354 * @return handle to the new monitoring client
356 static struct MonitoringClient *
357 setup_val_monitoring_client (struct GNUNET_SERVER_Client *client,
358 struct GNUNET_PeerIdentity *peer)
360 struct MonitoringClient *mc;
362 GNUNET_assert (NULL ==
363 lookup_monitoring_client (val_monitoring_clients_head,
365 mc = GNUNET_new (struct MonitoringClient);
368 GNUNET_CONTAINER_DLL_insert (val_monitoring_clients_head,
369 val_monitoring_clients_tail,
371 GNUNET_SERVER_notification_context_add (val_nc, client);
373 if (0 != memcmp (peer,
375 sizeof (struct GNUNET_PeerIdentity)))
376 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
377 "Client %p started monitoring of the peer `%s'\n",
381 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
382 "Client %p started monitoring all peers\n",
389 * Function called to notify a client about the socket being ready to
390 * queue more data. @a buf will be NULL and @a size zero if the socket
391 * was closed for writing in the meantime.
394 * @param size number of bytes available in @a buf
395 * @param buf where the callee should write the message
396 * @return number of bytes written to @a buf
399 transmit_to_client_callback (void *cls,
403 struct TransportClient *tc = cls;
404 struct ClientMessageQueueEntry *q;
405 const struct GNUNET_MessageHeader *msg;
413 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
414 "Transmission to client failed, closing connection.\n");
419 while (NULL != (q = tc->message_queue_head))
421 msg = (const struct GNUNET_MessageHeader *) &q[1];
422 msize = ntohs (msg->size);
423 if (msize + tsize > size)
425 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
426 "Transmitting message of type %u to client %p.\n",
429 GNUNET_CONTAINER_DLL_remove (tc->message_queue_head,
430 tc->message_queue_tail,
433 memcpy (&cbuf[tsize], msg, msize);
439 GNUNET_assert (msize >= sizeof (struct GNUNET_MessageHeader));
441 GNUNET_SERVER_notify_transmit_ready (tc->client, msize,
442 GNUNET_TIME_UNIT_FOREVER_REL,
443 &transmit_to_client_callback, tc);
444 GNUNET_assert (NULL != tc->th);
451 * Queue the given message for transmission to the given client
453 * @param tc target of the message
454 * @param msg message to transmit
455 * @param may_drop #GNUNET_YES if the message can be dropped
458 unicast (struct TransportClient *tc,
459 const struct GNUNET_MessageHeader *msg,
462 struct ClientMessageQueueEntry *q;
470 if ( (tc->message_count >= MAX_PENDING) &&
471 (GNUNET_YES == may_drop) )
473 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
474 "Dropping message of type %u and size %u, have %u/%u messages pending\n",
479 GNUNET_STATISTICS_update (GST_stats,
481 ("# messages dropped due to slow client"), 1,
485 msize = ntohs (msg->size);
486 GNUNET_assert (msize >= sizeof (struct GNUNET_MessageHeader));
487 q = GNUNET_malloc (sizeof (struct ClientMessageQueueEntry) + msize);
488 memcpy (&q[1], msg, msize);
489 GNUNET_CONTAINER_DLL_insert_tail (tc->message_queue_head,
490 tc->message_queue_tail,
496 GNUNET_SERVER_notify_transmit_ready (tc->client, msize,
497 GNUNET_TIME_UNIT_FOREVER_REL,
498 &transmit_to_client_callback, tc);
499 GNUNET_assert (NULL != tc->th);
504 * Called whenever a client is disconnected. Frees our
505 * resources associated with that client.
507 * @param cls closure, NULL
508 * @param client identification of the client
511 client_disconnect_notification (void *cls,
512 struct GNUNET_SERVER_Client *client)
514 struct TransportClient *tc;
515 struct MonitoringClient *mc;
516 struct ClientMessageQueueEntry *mqe;
520 mc = lookup_monitoring_client (peer_monitoring_clients_head,
524 GNUNET_CONTAINER_DLL_remove (peer_monitoring_clients_head,
525 peer_monitoring_clients_tail,
529 mc = lookup_monitoring_client (val_monitoring_clients_head,
533 GNUNET_CONTAINER_DLL_remove (val_monitoring_clients_head,
534 val_monitoring_clients_tail,
538 tc = lookup_client (client);
541 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
542 "Client %p disconnected, cleaning up.\n",
544 while (NULL != (mqe = tc->message_queue_head))
546 GNUNET_CONTAINER_DLL_remove (tc->message_queue_head,
547 tc->message_queue_tail,
552 GNUNET_CONTAINER_DLL_remove (clients_head, clients_tail, tc);
553 GNUNET_SERVER_client_set_user_context (client, NULL);
556 GNUNET_SERVER_notify_transmit_ready_cancel (tc->th);
559 GNUNET_break (0 == tc->message_count);
565 * Function called for each of our connected neighbours. Notify the
566 * client about the existing neighbour.
568 * @param cls the `struct TransportClient *` to notify
569 * @param peer identity of the neighbour
570 * @param address the address
571 * @param state the current state of the peer
572 * @param state_timeout the time out for the state
573 * @param bandwidth_in inbound bandwidth in NBO
574 * @param bandwidth_out outbound bandwidth in NBO
577 notify_client_about_neighbour (void *cls,
578 const struct GNUNET_PeerIdentity *peer,
579 const struct GNUNET_HELLO_Address *address,
580 enum GNUNET_TRANSPORT_PeerState state,
581 struct GNUNET_TIME_Absolute state_timeout,
582 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
583 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out)
585 struct TransportClient *tc = cls;
586 struct ConnectInfoMessage cim;
588 if (GNUNET_NO == GST_neighbours_test_connected (peer))
590 cim.header.size = htons (sizeof (struct ConnectInfoMessage));
591 cim.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT);
593 cim.quota_in = bandwidth_in;
594 cim.quota_out = bandwidth_out;
595 unicast (tc, &cim.header, GNUNET_NO);
600 * Initialize a normal client. We got a start message from this
601 * client, add him to the list of clients for broadcasting of inbound
605 * @param client the client
606 * @param message the start message that was sent
609 clients_handle_start (void *cls,
610 struct GNUNET_SERVER_Client *client,
611 const struct GNUNET_MessageHeader *message)
613 const struct StartMessage *start;
614 struct TransportClient *tc;
617 tc = lookup_client (client);
618 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
619 "Client %p sent START\n", tc);
622 /* got 'start' twice from the same client, not allowed */
624 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
627 start = (const struct StartMessage *) message;
628 options = ntohl (start->options);
629 if ((0 != (1 & options)) &&
631 memcmp (&start->self, &GST_my_identity,
632 sizeof (struct GNUNET_PeerIdentity))))
634 /* client thinks this is a different peer, reject */
636 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
639 tc = setup_client (client);
640 tc->send_payload = (0 != (2 & options));
644 GST_neighbours_iterate (¬ify_client_about_neighbour, tc);
645 GNUNET_SERVER_receive_done (client, GNUNET_OK);
650 * Client sent us a HELLO. Process the request.
653 * @param client the client
654 * @param message the HELLO message
657 clients_handle_hello (void *cls,
658 struct GNUNET_SERVER_Client *client,
659 const struct GNUNET_MessageHeader *message)
661 GST_validation_handle_hello (message);
662 GNUNET_SERVER_receive_done (client, GNUNET_OK);
667 * Closure for #handle_send_transmit_continuation()
669 struct SendTransmitContinuationContext
672 * Client that made the request.
674 struct GNUNET_SERVER_Client *client;
677 * Peer that was the target.
679 struct GNUNET_PeerIdentity target;
684 * Function called after the transmission is done. Notify the client that it is
685 * OK to send the next message.
688 * @param success #GNUNET_OK on success, #GNUNET_NO on failure, #GNUNET_SYSERR if we're not connected
689 * @param bytes_payload bytes payload sent
690 * @param bytes_on_wire bytes sent on wire
693 handle_send_transmit_continuation (void *cls,
695 size_t bytes_payload,
696 size_t bytes_on_wire)
698 struct SendTransmitContinuationContext *stcc = cls;
699 struct SendOkMessage send_ok_msg;
701 if (GNUNET_OK == success)
702 GST_neighbours_notify_payload_sent (&stcc->target,
704 send_ok_msg.header.size = htons (sizeof (send_ok_msg));
705 send_ok_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK);
706 send_ok_msg.bytes_msg = htonl (bytes_payload);
707 send_ok_msg.bytes_physical = htonl (bytes_on_wire);
708 send_ok_msg.success = htonl (success);
709 send_ok_msg.peer = stcc->target;
710 GST_clients_unicast (stcc->client,
713 GNUNET_SERVER_client_drop (stcc->client);
719 * Client asked for transmission to a peer. Process the request.
722 * @param client the client
723 * @param message the send message that was sent
726 clients_handle_send (void *cls,
727 struct GNUNET_SERVER_Client *client,
728 const struct GNUNET_MessageHeader *message)
730 const struct OutboundMessage *obm;
731 const struct GNUNET_MessageHeader *obmm;
732 struct SendTransmitContinuationContext *stcc;
735 struct TransportClient *tc;
737 tc = lookup_client (client);
740 /* client asked for transmission before 'START' */
742 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
746 size = ntohs (message->size);
748 sizeof (struct OutboundMessage) + sizeof (struct GNUNET_MessageHeader))
751 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
754 obm = (const struct OutboundMessage *) message;
755 obmm = (const struct GNUNET_MessageHeader *) &obm[1];
756 msize = size - sizeof (struct OutboundMessage);
757 if (msize < sizeof (struct GNUNET_MessageHeader))
760 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
764 if (GNUNET_NO == GST_neighbours_test_connected (&obm->peer))
766 /* not connected, not allowed to send; can happen due to asynchronous operations */
767 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
768 "Could not send message to peer `%s': not connected\n",
769 GNUNET_i2s (&obm->peer));
770 GNUNET_STATISTICS_update (GST_stats,
772 ("# bytes payload dropped (other peer was not connected)"),
774 GNUNET_SERVER_receive_done (client, GNUNET_OK);
777 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
778 "Received `%s' request from client with target `%4s' and first message of type %u and total size %u\n",
780 GNUNET_i2s (&obm->peer),
783 GNUNET_SERVER_receive_done (client, GNUNET_OK);
784 stcc = GNUNET_new (struct SendTransmitContinuationContext);
785 stcc->target = obm->peer;
786 stcc->client = client;
787 GNUNET_SERVER_client_keep (client);
788 GST_manipulation_send (&obm->peer, obmm, msize,
789 GNUNET_TIME_relative_ntoh (obm->timeout),
790 &handle_send_transmit_continuation, stcc);
795 * Try to initiate a connection to the given peer if the blacklist
798 * @param cls closure (unused, NULL)
799 * @param peer identity of peer that was tested
800 * @param result #GNUNET_OK if the connection is allowed,
804 try_connect_if_allowed (void *cls,
805 const struct GNUNET_PeerIdentity *peer,
808 if (GNUNET_OK != result)
810 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
811 _("Blacklist refuses connection attempt to peer `%s'\n"),
813 return; /* not allowed */
815 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
816 "Blacklist allows connection attempt to peer `%s'\n",
819 GST_neighbours_try_connect (peer);
824 * Handle request connect message
826 * @param cls closure (always NULL)
827 * @param client identification of the client
828 * @param message the actual message
831 clients_handle_request_connect (void *cls,
832 struct GNUNET_SERVER_Client *client,
833 const struct GNUNET_MessageHeader *message)
835 const struct TransportRequestConnectMessage *trcm;
837 trcm = (const struct TransportRequestConnectMessage *) message;
838 GNUNET_break (0 == ntohl (trcm->reserved));
839 GNUNET_STATISTICS_update (GST_stats,
841 ("# REQUEST CONNECT messages received"), 1,
843 if (0 == memcmp (&trcm->peer,
845 sizeof (struct GNUNET_PeerIdentity)))
848 GNUNET_SERVER_receive_done (client, GNUNET_OK);
851 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
852 "Received a request connect message for peer `%s'\n",
853 GNUNET_i2s (&trcm->peer));
854 (void) GST_blacklist_test_allowed (&trcm->peer,
856 &try_connect_if_allowed,
858 GNUNET_SERVER_receive_done (client, GNUNET_OK);
863 * Handle request disconnect message
865 * @param cls closure (always NULL)
866 * @param client identification of the client
867 * @param message the actual message
870 clients_handle_request_disconnect (void *cls,
871 struct GNUNET_SERVER_Client *client,
872 const struct GNUNET_MessageHeader *message)
874 const struct TransportRequestDisconnectMessage *trdm;
876 trdm = (const struct TransportRequestDisconnectMessage *) message;
877 GNUNET_break (0 == ntohl (trdm->reserved));
878 GNUNET_STATISTICS_update (GST_stats,
880 ("# REQUEST DISCONNECT messages received"), 1,
882 if (0 == memcmp (&trdm->peer,
884 sizeof (struct GNUNET_PeerIdentity)))
887 GNUNET_SERVER_receive_done (client, GNUNET_OK);
890 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
891 "Received a request disconnect message for peer `%s'\n",
892 GNUNET_i2s (&trdm->peer));
893 (void) GST_neighbours_force_disconnect (&trdm->peer);
894 GNUNET_SERVER_receive_done (client, GNUNET_OK);
899 * Take the given address and append it to the set of results sent back to
900 * the client. This function may be called serveral times for a single
901 * conversion. The last invocation will be with a @a address of
902 * NULL and a @a res of #GNUNET_OK. Thus, to indicate conversion
903 * errors, the callback might be called first with @a address NULL and
904 * @a res being #GNUNET_SYSERR. In that case, there will still be a
905 * subsequent call later with @a address NULL and @a res #GNUNET_OK.
907 * @param cls the transmission context used (`struct GNUNET_SERVER_TransmitContext *`)
908 * @param buf text to transmit (contains the human-readable address, or NULL)
909 * @param res #GNUNET_OK if conversion was successful, #GNUNET_SYSERR on error,
913 transmit_address_to_client (void *cls,
917 struct AddressToStringContext *actx = cls;
918 struct AddressToStringResultMessage *atsm;
922 GNUNET_assert ( (GNUNET_OK == res) ||
923 (GNUNET_SYSERR == res) );
926 len = sizeof (struct AddressToStringResultMessage);
927 atsm = GNUNET_malloc (len);
928 atsm->header.size = ntohs (len);
929 atsm->header.type = ntohs (GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_TO_STRING_REPLY);
930 if (GNUNET_OK == res)
932 /* this was the last call, transmit */
933 atsm->res = htonl (GNUNET_OK);
934 atsm->addr_len = htonl (0);
935 GNUNET_SERVER_transmit_context_append_message (actx->tc,
936 (const struct GNUNET_MessageHeader *) atsm);
937 GNUNET_SERVER_transmit_context_run (actx->tc,
938 GNUNET_TIME_UNIT_FOREVER_REL);
939 GNUNET_CONTAINER_DLL_remove (a2s_head,
946 if (GNUNET_SYSERR == res)
948 /* address conversion failed, but there will be more callbacks */
949 atsm->res = htonl (GNUNET_SYSERR);
950 atsm->addr_len = htonl (0);
951 GNUNET_SERVER_transmit_context_append_message (actx->tc,
952 (const struct GNUNET_MessageHeader *) atsm);
957 GNUNET_assert (GNUNET_OK == res);
958 /* succesful conversion, append*/
959 slen = strlen (buf) + 1;
960 len = sizeof (struct AddressToStringResultMessage) + slen;
961 atsm = GNUNET_malloc (len);
962 atsm->header.size = ntohs (len);
963 atsm->header.type = ntohs (GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_TO_STRING_REPLY);
964 atsm->res = htonl (GNUNET_YES);
965 atsm->addr_len = htonl (slen);
969 GNUNET_SERVER_transmit_context_append_message (actx->tc,
970 (const struct GNUNET_MessageHeader *) atsm);
976 * Client asked to resolve an address. Process the request.
979 * @param client the client
980 * @param message the resolution request
983 clients_handle_address_to_string (void *cls,
984 struct GNUNET_SERVER_Client *client,
985 const struct GNUNET_MessageHeader *message)
987 const struct AddressLookupMessage *alum;
988 struct GNUNET_TRANSPORT_PluginFunctions *papi;
989 const char *plugin_name;
991 uint32_t address_len;
993 struct GNUNET_SERVER_TransmitContext *tc;
994 struct AddressToStringContext *actx;
995 struct AddressToStringResultMessage atsm;
996 struct GNUNET_TIME_Relative rtimeout;
999 size = ntohs (message->size);
1000 if (size < sizeof (struct AddressLookupMessage))
1003 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1006 alum = (const struct AddressLookupMessage *) message;
1007 address_len = ntohs (alum->addrlen);
1008 if (size <= sizeof (struct AddressLookupMessage) + address_len)
1011 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1014 address = (const char *) &alum[1];
1015 plugin_name = (const char *) &address[address_len];
1016 if ('\0' != plugin_name[size - sizeof (struct AddressLookupMessage) - address_len - 1])
1019 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1022 rtimeout = GNUNET_TIME_relative_ntoh (alum->timeout);
1023 numeric = ntohs (alum->numeric_only);
1024 tc = GNUNET_SERVER_transmit_context_create (client);
1025 papi = GST_plugins_printer_find (plugin_name);
1028 atsm.header.size = ntohs (sizeof (struct AddressToStringResultMessage));
1029 atsm.header.type = ntohs (GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_TO_STRING_REPLY);
1030 atsm.res = htonl (GNUNET_SYSERR);
1031 atsm.addr_len = htonl (0);
1032 GNUNET_SERVER_transmit_context_append_message (tc,
1034 atsm.header.size = ntohs (sizeof (struct AddressToStringResultMessage));
1035 atsm.header.type = ntohs (GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_TO_STRING_REPLY);
1036 atsm.res = htonl (GNUNET_OK);
1037 atsm.addr_len = htonl (0);
1038 GNUNET_SERVER_transmit_context_append_message (tc,
1040 GNUNET_SERVER_transmit_context_run (tc, GNUNET_TIME_UNIT_FOREVER_REL);
1043 actx = GNUNET_new (struct AddressToStringContext);
1045 GNUNET_CONTAINER_DLL_insert (a2s_head, a2s_tail, actx);
1046 GNUNET_SERVER_disable_receive_done_warning (client);
1047 papi->address_pretty_printer (papi->cls,
1049 address, address_len,
1052 &transmit_address_to_client,
1058 * Compose #PeerIterateResponseMessage using the given peer and address.
1060 * @param peer identity of the peer
1061 * @param address the address, NULL on disconnect
1062 * @return composed message
1064 static struct PeerIterateResponseMessage *
1065 compose_address_iterate_response_message (const struct GNUNET_PeerIdentity *peer,
1066 const struct GNUNET_HELLO_Address *address)
1068 struct PeerIterateResponseMessage *msg;
1074 GNUNET_assert (NULL != peer);
1075 if (NULL != address)
1077 tlen = strlen (address->transport_name) + 1;
1078 alen = address->address_length;
1082 size = (sizeof (struct PeerIterateResponseMessage) + alen + tlen);
1083 msg = GNUNET_malloc (size);
1084 msg->header.size = htons (size);
1086 htons (GNUNET_MESSAGE_TYPE_TRANSPORT_MONITOR_PEER_RESPONSE);
1087 msg->reserved = htonl (0);
1089 msg->addrlen = htonl (alen);
1090 msg->pluginlen = htonl (tlen);
1092 if (NULL != address)
1094 msg->local_address_info = htonl((uint32_t) address->local_info);
1095 addr = (char *) &msg[1];
1096 memcpy (addr, address->address, alen);
1097 memcpy (&addr[alen], address->transport_name, tlen);
1104 * Compose #PeerIterateResponseMessage using the given peer and address.
1106 * @param peer identity of the peer
1107 * @param address the address, NULL on disconnect
1108 * @return composed message
1110 static struct ValidationIterateResponseMessage *
1111 compose_validation_iterate_response_message (const struct GNUNET_PeerIdentity *peer,
1112 const struct GNUNET_HELLO_Address *address)
1114 struct ValidationIterateResponseMessage *msg;
1120 GNUNET_assert (NULL != peer);
1121 if (NULL != address)
1123 tlen = strlen (address->transport_name) + 1;
1124 alen = address->address_length;
1131 size = (sizeof (struct ValidationIterateResponseMessage) + alen + tlen);
1132 msg = GNUNET_malloc (size);
1133 msg->header.size = htons (size);
1135 htons (GNUNET_MESSAGE_TYPE_TRANSPORT_MONITOR_VALIDATION_RESPONSE);
1136 msg->reserved = htonl (0);
1138 msg->addrlen = htonl (alen);
1139 msg->pluginlen = htonl (tlen);
1141 if (NULL != address)
1143 msg->local_address_info = htonl((uint32_t) address->local_info);
1144 addr = (char *) &msg[1];
1145 memcpy (addr, address->address, alen);
1146 memcpy (&addr[alen], address->transport_name, tlen);
1153 * Context for #send_validation_information() and
1154 * #send_peer_information().
1156 struct IterationContext
1159 * Context to use for the transmission.
1161 struct GNUNET_SERVER_TransmitContext *tc;
1164 * Which peers do we care about?
1166 struct GNUNET_PeerIdentity id;
1169 * #GNUNET_YES if @e id should be ignored because we want all peers.
1176 * Output information of validation entries to the given client.
1178 * @param cls the `struct IterationContext *`
1179 * @param peer identity of the neighbour
1180 * @param address the address
1181 * @param last_validation point in time when last validation was performed
1182 * @param valid_until point in time how long address is valid
1183 * @param next_validation point in time when next validation will be performed
1184 * @param state state of validation notification
1187 send_validation_information (void *cls,
1188 const struct GNUNET_PeerIdentity *peer,
1189 const struct GNUNET_HELLO_Address *address,
1190 struct GNUNET_TIME_Absolute last_validation,
1191 struct GNUNET_TIME_Absolute valid_until,
1192 struct GNUNET_TIME_Absolute next_validation,
1193 enum GNUNET_TRANSPORT_ValidationState state)
1195 struct IterationContext *pc = cls;
1196 struct ValidationIterateResponseMessage *msg;
1198 if ( (GNUNET_YES != pc->all) &&
1199 (0 != memcmp (peer, &pc->id, sizeof (pc->id))) )
1201 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1202 "Sending information about for validation entry for peer `%s' using address `%s'\n",
1204 (NULL != address) ? GST_plugins_a2s (address) : "<none>");
1205 msg = compose_validation_iterate_response_message (peer, address);
1206 msg->last_validation = GNUNET_TIME_absolute_hton(last_validation);
1207 msg->valid_until = GNUNET_TIME_absolute_hton(valid_until);
1208 msg->next_validation = GNUNET_TIME_absolute_hton(next_validation);
1209 msg->state = htonl ((uint32_t) state);
1210 GNUNET_SERVER_transmit_context_append_message (pc->tc, &msg->header);
1216 * Output information of neighbours to the given client.
1218 * @param cls the `struct PeerIterationContext *`
1219 * @param peer identity of the neighbour
1220 * @param address the address
1221 * @param state current state this peer is in
1222 * @param state_timeout timeout for the current state of the peer
1223 * @param bandwidth_in inbound quota in NBO
1224 * @param bandwidth_out outbound quota in NBO
1227 send_peer_information (void *cls,
1228 const struct GNUNET_PeerIdentity *peer,
1229 const struct GNUNET_HELLO_Address *address,
1230 enum GNUNET_TRANSPORT_PeerState state,
1231 struct GNUNET_TIME_Absolute state_timeout,
1232 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
1233 struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out)
1235 struct IterationContext *pc = cls;
1236 struct PeerIterateResponseMessage *msg;
1238 if ( (GNUNET_YES != pc->all) &&
1239 (0 != memcmp (peer, &pc->id, sizeof (pc->id))) )
1241 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1242 "Sending information about `%s' using address `%s' in state `%s'\n",
1244 (NULL != address) ? GST_plugins_a2s (address) : "<none>",
1245 GNUNET_TRANSPORT_ps2s (state));
1246 msg = compose_address_iterate_response_message (peer, address);
1247 msg->state = htonl (state);
1248 msg->state_timeout = GNUNET_TIME_absolute_hton(state_timeout);
1249 GNUNET_SERVER_transmit_context_append_message (pc->tc, &msg->header);
1255 * Client asked to obtain information about a specific or all peers
1256 * Process the request.
1259 * @param client the client
1260 * @param message the peer address information request
1263 clients_handle_monitor_peers (void *cls,
1264 struct GNUNET_SERVER_Client *client,
1265 const struct GNUNET_MessageHeader *message)
1267 struct GNUNET_SERVER_TransmitContext *tc;
1268 const struct PeerMonitorMessage *msg;
1269 struct IterationContext pc;
1271 msg = (const struct PeerMonitorMessage *) message;
1272 if ( (GNUNET_YES != ntohl (msg->one_shot)) &&
1273 (NULL != lookup_monitoring_client (peer_monitoring_clients_head,
1277 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1280 GNUNET_SERVER_disable_receive_done_warning (client);
1281 GNUNET_SERVER_client_mark_monitor (client);
1282 pc.tc = tc = GNUNET_SERVER_transmit_context_create (client);
1284 /* Send initial list */
1285 if (0 == memcmp (&msg->peer,
1287 sizeof (struct GNUNET_PeerIdentity)))
1289 /* iterate over all neighbours */
1290 pc.all = GNUNET_YES;
1295 /* just return one neighbour */
1299 GST_neighbours_iterate (&send_peer_information, &pc);
1301 if (GNUNET_YES != ntohl (msg->one_shot))
1303 setup_peer_monitoring_client (client, &msg->peer);
1307 GNUNET_SERVER_transmit_context_append_data (tc, NULL, 0,
1308 GNUNET_MESSAGE_TYPE_TRANSPORT_MONITOR_PEER_RESPONSE);
1311 GNUNET_SERVER_transmit_context_run (tc, GNUNET_TIME_UNIT_FOREVER_REL);
1316 * Client asked to obtain information about a specific or all validation
1320 * @param client the client
1321 * @param message the peer address information request
1324 clients_handle_monitor_validation (void *cls,
1325 struct GNUNET_SERVER_Client *client,
1326 const struct GNUNET_MessageHeader *message)
1328 struct GNUNET_SERVER_TransmitContext *tc;
1329 struct PeerMonitorMessage *msg;
1330 struct IterationContext pc;
1332 if (ntohs (message->type) != GNUNET_MESSAGE_TYPE_TRANSPORT_MONITOR_VALIDATION_REQUEST)
1335 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1338 if (ntohs (message->size) != sizeof (struct ValidationMonitorMessage))
1341 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1344 msg = (struct PeerMonitorMessage *) message;
1345 if ( (GNUNET_YES != ntohl (msg->one_shot)) &&
1346 (NULL != lookup_monitoring_client (val_monitoring_clients_head, client)) )
1349 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
1352 GNUNET_SERVER_disable_receive_done_warning (client);
1353 GNUNET_SERVER_client_mark_monitor (client);
1354 pc.tc = tc = GNUNET_SERVER_transmit_context_create (client);
1356 /* Send initial list */
1357 if (0 == memcmp (&msg->peer,
1359 sizeof (struct GNUNET_PeerIdentity)))
1361 /* iterate over all neighbours */
1362 pc.all = GNUNET_YES;
1367 /* just return one neighbour */
1371 GST_validation_iterate (&send_validation_information,
1374 if (GNUNET_YES != ntohl (msg->one_shot))
1376 setup_val_monitoring_client (client, &msg->peer);
1380 GNUNET_SERVER_transmit_context_append_data (tc, NULL, 0,
1381 GNUNET_MESSAGE_TYPE_TRANSPORT_MONITOR_VALIDATION_RESPONSE);
1383 GNUNET_SERVER_transmit_context_run (tc, GNUNET_TIME_UNIT_FOREVER_REL);
1388 * Function called by the plugin with information about the
1389 * current sessions managed by the plugin (for monitoring).
1391 * @param cls closure
1392 * @param session session handle this information is about,
1393 * NULL to indicate that we are "in sync" (initial
1394 * iteration complete)
1395 * @param info information about the state of the session,
1396 * NULL if @a session is also NULL and we are
1397 * merely signalling that the initial iteration is over
1400 plugin_session_info_cb (void *cls,
1401 struct Session *session,
1402 const struct GNUNET_TRANSPORT_SessionInfo *info)
1404 struct TransportPluginMonitorMessage *msg;
1405 struct GNUNET_MessageHeader sync;
1412 if (0 == GNUNET_SERVER_notification_context_get_size (plugin_nc))
1414 fprintf (stderr, "UNSUB!\n");
1415 GST_plugins_monitor_subscribe (NULL, NULL);
1418 if ( (NULL == info) &&
1421 /* end of initial iteration */
1422 if (NULL != sync_client)
1424 sync.size = htons (sizeof (struct GNUNET_MessageHeader));
1425 sync.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_MONITOR_PLUGIN_SYNC);
1426 GNUNET_SERVER_notification_context_unicast (plugin_nc,
1434 GNUNET_assert (NULL != info);
1435 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1436 "Plugin event for peer %s on transport %s\n",
1437 GNUNET_i2s (&info->address->peer),
1438 info->address->transport_name);
1439 slen = strlen (info->address->transport_name) + 1;
1440 alen = info->address->address_length;
1441 size = sizeof (struct TransportPluginMonitorMessage) + slen + alen;
1442 if (size > UINT16_MAX)
1447 msg = GNUNET_malloc (size);
1448 msg->header.size = htons (size);
1449 msg->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_MONITOR_PLUGIN_EVENT);
1450 msg->session_state = htons ((uint16_t) info->state);
1451 msg->is_inbound = htons ((int16_t) info->is_inbound);
1452 msg->msgs_pending = htonl (info->num_msg_pending);
1453 msg->bytes_pending = htonl (info->num_bytes_pending);
1454 msg->timeout = GNUNET_TIME_absolute_hton (info->session_timeout);
1455 msg->delay = GNUNET_TIME_absolute_hton (info->receive_delay);
1456 msg->peer = info->address->peer;
1457 msg->session_id = (uint64_t) (intptr_t) session;
1458 msg->plugin_name_len = htons (slen);
1459 msg->plugin_address_len = htons (alen);
1460 name = (char *) &msg[1];
1461 memcpy (name, info->address->transport_name, slen);
1462 addr = &name[slen + 1];
1463 memcpy (addr, info->address->address, alen);
1464 if (NULL != sync_client)
1465 GNUNET_SERVER_notification_context_unicast (plugin_nc,
1470 GNUNET_SERVER_notification_context_broadcast (plugin_nc,
1478 * Client asked to obtain information about all plugin connections.
1481 * @param client the client
1482 * @param message the peer address information request
1485 clients_handle_monitor_plugins (void *cls,
1486 struct GNUNET_SERVER_Client *client,
1487 const struct GNUNET_MessageHeader *message)
1489 GNUNET_SERVER_client_mark_monitor (client);
1490 GNUNET_SERVER_disable_receive_done_warning (client);
1491 GNUNET_SERVER_notification_context_add (plugin_nc, client);
1492 sync_client = client;
1493 GST_plugins_monitor_subscribe (&plugin_session_info_cb, NULL);
1498 * Start handling requests from clients.
1500 * @param server server used to accept clients from.
1503 GST_clients_start (struct GNUNET_SERVER_Handle *server)
1505 static const struct GNUNET_SERVER_MessageHandler handlers[] = {
1506 {&clients_handle_start, NULL,
1507 GNUNET_MESSAGE_TYPE_TRANSPORT_START, sizeof (struct StartMessage)},
1508 {&clients_handle_hello, NULL,
1509 GNUNET_MESSAGE_TYPE_HELLO, 0},
1510 {&clients_handle_send, NULL,
1511 GNUNET_MESSAGE_TYPE_TRANSPORT_SEND, 0},
1512 {&clients_handle_request_connect, NULL,
1513 GNUNET_MESSAGE_TYPE_TRANSPORT_REQUEST_CONNECT,
1514 sizeof (struct TransportRequestConnectMessage)},
1515 {&clients_handle_request_disconnect, NULL,
1516 GNUNET_MESSAGE_TYPE_TRANSPORT_REQUEST_DISCONNECT,
1517 sizeof (struct TransportRequestDisconnectMessage)},
1518 {&clients_handle_address_to_string, NULL,
1519 GNUNET_MESSAGE_TYPE_TRANSPORT_ADDRESS_TO_STRING, 0},
1520 {&clients_handle_monitor_peers, NULL,
1521 GNUNET_MESSAGE_TYPE_TRANSPORT_MONITOR_PEER_REQUEST,
1522 sizeof (struct PeerMonitorMessage)},
1523 {&clients_handle_monitor_validation, NULL,
1524 GNUNET_MESSAGE_TYPE_TRANSPORT_MONITOR_VALIDATION_REQUEST,
1525 sizeof (struct ValidationMonitorMessage)},
1526 {&GST_blacklist_handle_init, NULL,
1527 GNUNET_MESSAGE_TYPE_TRANSPORT_BLACKLIST_INIT,
1528 sizeof (struct GNUNET_MessageHeader)},
1529 {&GST_blacklist_handle_reply, NULL,
1530 GNUNET_MESSAGE_TYPE_TRANSPORT_BLACKLIST_REPLY,
1531 sizeof (struct BlacklistMessage)},
1532 {&GST_manipulation_set_metric, NULL,
1533 GNUNET_MESSAGE_TYPE_TRANSPORT_TRAFFIC_METRIC, 0},
1534 {&clients_handle_monitor_plugins, NULL,
1535 GNUNET_MESSAGE_TYPE_TRANSPORT_MONITOR_PLUGIN_START,
1536 sizeof (struct GNUNET_MessageHeader) },
1539 peer_nc = GNUNET_SERVER_notification_context_create (server, 0);
1540 val_nc = GNUNET_SERVER_notification_context_create (server, 0);
1541 plugin_nc = GNUNET_SERVER_notification_context_create (server, 0);
1542 GNUNET_SERVER_add_handlers (server, handlers);
1543 GNUNET_SERVER_disconnect_notify (server,
1544 &client_disconnect_notification,
1550 * Stop processing clients.
1555 struct AddressToStringContext *cur;
1557 while (NULL != (cur = a2s_head))
1559 GNUNET_SERVER_transmit_context_destroy (cur->tc, GNUNET_NO);
1560 GNUNET_CONTAINER_DLL_remove (a2s_head, a2s_tail, cur);
1563 if (NULL != peer_nc)
1565 GNUNET_SERVER_notification_context_destroy (peer_nc);
1570 GNUNET_SERVER_notification_context_destroy (val_nc);
1573 if (NULL != plugin_nc)
1575 GNUNET_SERVER_notification_context_destroy (plugin_nc);
1582 * Broadcast the given message to all of our clients.
1584 * @param msg message to broadcast
1585 * @param may_drop #GNUNET_YES if the message can be dropped / is payload
1588 GST_clients_broadcast (const struct GNUNET_MessageHeader *msg,
1591 struct TransportClient *tc;
1593 for (tc = clients_head; NULL != tc; tc = tc->next)
1595 if ( (GNUNET_YES == may_drop) &&
1596 (GNUNET_YES != tc->send_payload) )
1597 continue; /* skip, this client does not care about payload */
1598 unicast (tc, msg, may_drop);
1604 * Send the given message to a particular client
1606 * @param client target of the message
1607 * @param msg message to transmit
1608 * @param may_drop #GNUNET_YES if the message can be dropped
1611 GST_clients_unicast (struct GNUNET_SERVER_Client *client,
1612 const struct GNUNET_MessageHeader *msg,
1615 struct TransportClient *tc;
1617 tc = lookup_client (client);
1619 return; /* client got disconnected in the meantime, drop message */
1620 unicast (tc, msg, may_drop);
1625 * Broadcast the new active address to all clients monitoring the peer.
1627 * @param peer peer this update is about (never NULL)
1628 * @param address address, NULL on disconnect
1629 * @param state the current state of the peer
1630 * @param state_timeout the time out for the state
1633 GST_clients_broadcast_peer_notification (const struct GNUNET_PeerIdentity *peer,
1634 const struct GNUNET_HELLO_Address *address,
1635 enum GNUNET_TRANSPORT_PeerState state,
1636 struct GNUNET_TIME_Absolute state_timeout)
1638 struct PeerIterateResponseMessage *msg;
1639 struct MonitoringClient *mc;
1641 msg = compose_address_iterate_response_message (peer, address);
1642 msg->state = htonl (state);
1643 msg->state_timeout = GNUNET_TIME_absolute_hton (state_timeout);
1644 for (mc = peer_monitoring_clients_head; NULL != mc; mc = mc->next)
1645 if ((0 == memcmp (&mc->peer, &all_zeros,
1646 sizeof (struct GNUNET_PeerIdentity))) ||
1647 (0 == memcmp (&mc->peer, peer,
1648 sizeof (struct GNUNET_PeerIdentity))))
1649 GNUNET_SERVER_notification_context_unicast (peer_nc,
1658 * Broadcast the new validation changes to all clients monitoring the peer.
1660 * @param peer peer this update is about (never NULL)
1661 * @param address address, NULL on disconnect
1662 * @param last_validation point in time when last validation was performed
1663 * @param valid_until point in time how long address is valid
1664 * @param next_validation point in time when next validation will be performed
1665 * @param state state of validation notification
1668 GST_clients_broadcast_validation_notification (const struct GNUNET_PeerIdentity *peer,
1669 const struct GNUNET_HELLO_Address *address,
1670 struct GNUNET_TIME_Absolute last_validation,
1671 struct GNUNET_TIME_Absolute valid_until,
1672 struct GNUNET_TIME_Absolute next_validation,
1673 enum GNUNET_TRANSPORT_ValidationState state)
1675 struct ValidationIterateResponseMessage *msg;
1676 struct MonitoringClient *mc;
1678 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1679 "Sending information about for validation entry for peer `%s' using address `%s'\n",
1681 (address != NULL) ? GST_plugins_a2s (address) : "<none>");
1682 msg = compose_validation_iterate_response_message (peer, address);
1683 msg->last_validation = GNUNET_TIME_absolute_hton(last_validation);
1684 msg->valid_until = GNUNET_TIME_absolute_hton(valid_until);
1685 msg->next_validation = GNUNET_TIME_absolute_hton(next_validation);
1686 msg->state = htonl ((uint32_t) state);
1687 for (mc = val_monitoring_clients_head; NULL != mc; mc = mc->next)
1688 if ((0 == memcmp (&mc->peer, &all_zeros,
1689 sizeof (struct GNUNET_PeerIdentity))) ||
1690 (0 == memcmp (&mc->peer, peer,
1691 sizeof (struct GNUNET_PeerIdentity))))
1692 GNUNET_SERVER_notification_context_unicast (val_nc,
1700 /* end of file gnunet-service-transport_clients.c */