2 This file is part of GNUnet.
3 (C) 2009 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
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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.c
23 * @brief low-level P2P messaging
24 * @author Christian Grothoff
27 * - if we do not receive an ACK in response to our
28 * HELLO, retransmit HELLO!
31 #include "gnunet_client_lib.h"
32 #include "gnunet_constants.h"
33 #include "gnunet_getopt_lib.h"
34 #include "gnunet_hello_lib.h"
35 #include "gnunet_os_lib.h"
36 #include "gnunet_peerinfo_service.h"
37 #include "gnunet_plugin_lib.h"
38 #include "gnunet_protocols.h"
39 #include "gnunet_service_lib.h"
40 #include "gnunet_signatures.h"
41 #include "plugin_transport.h"
42 #include "transport.h"
45 * How many messages can we have pending for a given client process
46 * before we start to drop incoming messages? We typically should
47 * have only one client and so this would be the primary buffer for
48 * messages, so the number should be chosen rather generously.
50 * The expectation here is that most of the time the queue is large
51 * enough so that a drop is virtually never required.
53 #define MAX_PENDING 128
56 * How often should we try to reconnect to a peer using a particular
57 * transport plugin before giving up? Note that the plugin may be
58 * added back to the list after PLUGIN_RETRY_FREQUENCY expires.
60 #define MAX_CONNECT_RETRY 3
63 * How often must a peer violate bandwidth quotas before we start
64 * to simply drop its messages?
66 #define QUOTA_VIOLATION_DROP_THRESHOLD 100
69 * How long until a HELLO verification attempt should time out?
71 #define HELLO_VERIFICATION_TIMEOUT GNUNET_TIME_UNIT_MINUTES
74 * How often do we re-add (cheaper) plugins to our list of plugins
75 * to try for a given connected peer?
77 #define PLUGIN_RETRY_FREQUENCY GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 15)
80 * After how long do we expire an address in a HELLO
81 * that we just validated? This value is also used
82 * for our own addresses when we create a HELLO.
84 #define HELLO_ADDRESS_EXPIRATION GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 12)
88 * Entry in linked list of network addresses.
93 * This is a linked list.
95 struct AddressList *next;
98 * The address, actually a pointer to the end
99 * of this struct. Do not free!
104 * How long until we auto-expire this address (unless it is
105 * re-confirmed by the transport)?
107 struct GNUNET_TIME_Absolute expires;
118 * Entry in linked list of all of our plugins.
120 struct TransportPlugin
124 * This is a linked list.
126 struct TransportPlugin *next;
129 * API of the transport as returned by the plugin's
130 * initialization function.
132 struct GNUNET_TRANSPORT_PluginFunctions *api;
135 * Short name for the plugin (i.e. "tcp").
140 * Name of the library (i.e. "gnunet_plugin_transport_tcp").
145 * List of our known addresses for this transport.
147 struct AddressList *addresses;
150 * Environment this transport service is using
153 struct GNUNET_TRANSPORT_PluginEnvironment env;
156 * ID of task that is used to clean up expired addresses.
158 GNUNET_SCHEDULER_TaskIdentifier address_update_task;
162 * Set to GNUNET_YES if we need to scrap the existing
163 * list of "addresses" and start fresh when we receive
164 * the next address update from a transport. Set to
165 * GNUNET_NO if we should just add the new address
166 * to the list and wait for the commit call.
171 struct NeighbourList;
174 * For each neighbour we keep a list of messages
175 * that we still want to transmit to the neighbour.
181 * This is a linked list.
183 struct MessageQueue *next;
186 * The message we want to transmit.
188 struct GNUNET_MessageHeader *message;
191 * Client responsible for queueing the message;
192 * used to check that a client has not two messages
193 * pending for the same target. Can be NULL.
195 struct TransportClient *client;
198 * Neighbour this entry belongs to.
200 struct NeighbourList *neighbour;
203 * Plugin that we used for the transmission.
204 * NULL until we scheduled a transmission.
206 struct TransportPlugin *plugin;
209 * Internal message of the transport system that should not be
210 * included in the usual SEND-SEND_OK transmission confirmation
211 * traffic management scheme. Typically, "internal_msg" will
212 * be set whenever "client" is NULL (but it is not strictly
218 * How important is the message?
220 unsigned int priority;
226 * For a given Neighbour, which plugins are available
227 * to talk to this peer and what are their costs?
233 * This is a linked list.
235 struct ReadyList *next;
238 * Which of our transport plugins does this entry
241 struct TransportPlugin *plugin;
244 * Neighbour this entry belongs to.
246 struct NeighbourList *neighbour;
249 * Opaque handle (specific to the plugin) for the
250 * connection to our target; can be NULL.
255 * What was the last latency observed for this plugin
256 * and peer? Invalid if connected is GNUNET_NO.
258 struct GNUNET_TIME_Relative latency;
261 * If we did not successfully transmit a message to the
262 * given peer via this connection during the specified
263 * time, we should consider the connection to be dead.
264 * This is used in the case that a TCP transport simply
265 * stalls writing to the stream but does not formerly
266 * get a signal that the other peer died.
268 struct GNUNET_TIME_Absolute timeout;
271 * Is this plugin currently connected? The first time
272 * we transmit or send data to a peer via a particular
273 * plugin, we set this to GNUNET_YES. If we later get
274 * an error (disconnect notification or transmission
275 * failure), we set it back to GNUNET_NO. Each time the
276 * value is set to GNUNET_YES, we increment the
277 * "connect_attempts" counter. If that one reaches a
278 * particular threshold, we consider the plugin to not
279 * be working properly at this time for the given peer
280 * and remove it from the eligible list.
285 * How often have we tried to connect using this plugin?
287 unsigned int connect_attempts;
290 * Is this plugin ready to transmit to the specific
291 * target? GNUNET_NO if not. Initially, all plugins
292 * are marked ready. If a transmission is in progress,
293 * "transmit_ready" is set to GNUNET_NO.
301 * Entry in linked list of all of our current neighbours.
307 * This is a linked list.
309 struct NeighbourList *next;
312 * Which of our transports is connected to this peer
313 * and what is their status?
315 struct ReadyList *plugins;
318 * List of messages we would like to send to this peer;
319 * must contain at most one message per client.
321 struct MessageQueue *messages;
324 * Identity of this neighbour.
326 struct GNUNET_PeerIdentity id;
329 * ID of task scheduled to run when this peer is about to
330 * time out (will free resources associated with the peer).
332 GNUNET_SCHEDULER_TaskIdentifier timeout_task;
335 * How long until we should consider this peer dead
336 * (if we don't receive another message in the
339 struct GNUNET_TIME_Absolute peer_timeout;
342 * At what time did we reset last_received last?
344 struct GNUNET_TIME_Absolute last_quota_update;
347 * At what time should we try to again add plugins to
350 struct GNUNET_TIME_Absolute retry_plugins_time;
353 * How many bytes have we received since the "last_quota_update"
356 uint64_t last_received;
359 * Global quota for inbound traffic for the neighbour in bytes/ms.
364 * How often has the other peer (recently) violated the
365 * inbound traffic limit? Incremented by 10 per violation,
366 * decremented by 1 per non-violation (for each
369 unsigned int quota_violation_count;
372 * Have we seen an ACK from this neighbour in the past?
373 * (used to make up a fake ACK for clients connecting after
374 * the neighbour connected to us).
382 * Linked list of messages to be transmitted to
383 * the client. Each entry is followed by the
386 struct ClientMessageQueueEntry
389 * This is a linked list.
391 struct ClientMessageQueueEntry *next;
396 * Client connected to the transport service.
398 struct TransportClient
402 * This is a linked list.
404 struct TransportClient *next;
407 * Handle to the client.
409 struct GNUNET_SERVER_Client *client;
412 * Linked list of messages yet to be transmitted to
415 struct ClientMessageQueueEntry *message_queue_head;
418 * Tail of linked list of messages yet to be transmitted to the
421 struct ClientMessageQueueEntry *message_queue_tail;
424 * Is a call to "transmit_send_continuation" pending? If so, we
425 * must not free this struct (even if the corresponding client
426 * disconnects) and instead only remove it from the linked list and
427 * set the "client" field to NULL.
432 * Length of the list of messages pending for this client.
434 unsigned int message_count;
440 * For each HELLO, we may have to validate multiple addresses;
441 * each address gets its own request entry.
443 struct ValidationAddress
446 * This is a linked list.
448 struct ValidationAddress *next;
451 * Name of the transport.
453 char *transport_name;
456 * When should this validated address expire?
458 struct GNUNET_TIME_Absolute expiration;
461 * Length of the address we are validating.
466 * Challenge number we used.
471 * Set to GNUNET_YES if the challenge was met,
472 * GNUNET_SYSERR if we know it failed, GNUNET_NO
473 * if we are waiting on a response.
480 * Entry in linked list of all HELLOs awaiting validation.
482 struct ValidationList
486 * This is a linked list.
488 struct ValidationList *next;
491 * Linked list with one entry per address from the HELLO
492 * that needs to be validated.
494 struct ValidationAddress *addresses;
497 * The public key of the peer.
499 struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded publicKey;
502 * When does this record time-out? (assuming the
503 * challenge goes unanswered)
505 struct GNUNET_TIME_Absolute timeout;
511 * HELLOs awaiting validation.
513 static struct ValidationList *pending_validations;
518 static struct GNUNET_HELLO_Message *our_hello;
521 * "version" of "our_hello". Used to see if a given
522 * neighbour has already been sent the latest version
523 * of our HELLO message.
525 static unsigned int our_hello_version;
530 static struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded my_public_key;
535 static struct GNUNET_PeerIdentity my_identity;
540 static struct GNUNET_CRYPTO_RsaPrivateKey *my_private_key;
545 struct GNUNET_SCHEDULER_Handle *sched;
550 struct GNUNET_CONFIGURATION_Handle *cfg;
553 * Linked list of all clients to this service.
555 static struct TransportClient *clients;
558 * All loaded plugins.
560 static struct TransportPlugin *plugins;
565 static struct GNUNET_SERVER_Handle *server;
568 * All known neighbours and their HELLOs.
570 static struct NeighbourList *neighbours;
573 * Number of neighbours we'd like to have.
575 static uint32_t max_connect_per_transport;
579 * Find an entry in the neighbour list for a particular peer.
581 * @return NULL if not found.
583 static struct NeighbourList *
584 find_neighbour (const struct GNUNET_PeerIdentity *key)
586 struct NeighbourList *head = neighbours;
587 while ((head != NULL) &&
588 (0 != memcmp (key, &head->id, sizeof (struct GNUNET_PeerIdentity))))
595 * Find an entry in the transport list for a particular transport.
597 * @return NULL if not found.
599 static struct TransportPlugin *
600 find_transport (const char *short_name)
602 struct TransportPlugin *head = plugins;
603 while ((head != NULL) && (0 != strcmp (short_name, head->short_name)))
610 * Update the quota values for the given neighbour now.
613 update_quota (struct NeighbourList *n)
615 struct GNUNET_TIME_Relative delta;
619 delta = GNUNET_TIME_absolute_get_duration (n->last_quota_update);
620 if (delta.value < MIN_QUOTA_REFRESH_TIME)
621 return; /* not enough time passed for doing quota update */
622 allowed = delta.value * n->quota_in;
623 if (n->last_received < allowed)
625 remaining = allowed - n->last_received;
627 remaining /= n->quota_in;
630 if (remaining > MAX_BANDWIDTH_CARRY)
631 remaining = MAX_BANDWIDTH_CARRY;
632 n->last_received = 0;
633 n->last_quota_update = GNUNET_TIME_absolute_get ();
634 n->last_quota_update.value -= remaining;
635 if (n->quota_violation_count > 0)
636 n->quota_violation_count--;
640 n->last_received -= allowed;
641 n->last_quota_update = GNUNET_TIME_absolute_get ();
642 if (n->last_received > allowed)
644 /* more than twice the allowed rate! */
645 n->quota_violation_count += 10;
652 * Function called to notify a client about the socket
653 * being ready to queue more data. "buf" will be
654 * NULL and "size" zero if the socket was closed for
655 * writing in the meantime.
658 * @param size number of bytes available in buf
659 * @param buf where the callee should write the message
660 * @return number of bytes written to buf
663 transmit_to_client_callback (void *cls, size_t size, void *buf)
665 struct TransportClient *client = cls;
666 struct ClientMessageQueueEntry *q;
669 const struct GNUNET_MessageHeader *msg;
670 struct GNUNET_NETWORK_TransmitHandle *th;
675 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
676 "Transmission to client failed, closing connection.\n");
677 /* fatal error with client, free message queue! */
678 while (NULL != (q = client->message_queue_head))
680 client->message_queue_head = q->next;
683 client->message_queue_tail = NULL;
684 client->message_count = 0;
689 while (NULL != (q = client->message_queue_head))
691 msg = (const struct GNUNET_MessageHeader *) &q[1];
692 msize = ntohs (msg->size);
693 if (msize + tsize > size)
695 client->message_queue_head = q->next;
697 client->message_queue_tail = NULL;
698 memcpy (&cbuf[tsize], msg, msize);
701 client->message_count--;
703 GNUNET_assert (tsize > 0);
706 th = GNUNET_SERVER_notify_transmit_ready (client->client,
708 GNUNET_TIME_UNIT_FOREVER_REL,
709 &transmit_to_client_callback,
711 GNUNET_assert (th != NULL);
718 * Send the specified message to the specified client. Since multiple
719 * messages may be pending for the same client at a time, this code
720 * makes sure that no message is lost.
722 * @param client client to transmit the message to
723 * @param msg the message to send
724 * @param may_drop can this message be dropped if the
725 * message queue for this client is getting far too large?
728 transmit_to_client (struct TransportClient *client,
729 const struct GNUNET_MessageHeader *msg, int may_drop)
731 struct ClientMessageQueueEntry *q;
733 struct GNUNET_NETWORK_TransmitHandle *th;
735 if ((client->message_count >= MAX_PENDING) && (GNUNET_YES == may_drop))
737 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
739 ("Dropping message, have %u messages pending (%u is the soft limit)\n"),
740 client->message_count, MAX_PENDING);
741 /* TODO: call to statistics... */
744 client->message_count++;
745 msize = ntohs (msg->size);
746 q = GNUNET_malloc (sizeof (struct ClientMessageQueueEntry) + msize);
747 memcpy (&q[1], msg, msize);
748 /* append to message queue */
749 if (client->message_queue_tail == NULL)
751 client->message_queue_tail = q;
755 client->message_queue_tail->next = q;
756 client->message_queue_tail = q;
758 if (client->message_queue_head == NULL)
760 client->message_queue_head = q;
761 th = GNUNET_SERVER_notify_transmit_ready (client->client,
763 GNUNET_TIME_UNIT_FOREVER_REL,
764 &transmit_to_client_callback,
766 GNUNET_assert (th != NULL);
772 * Find alternative plugins for communication.
774 * @param neighbour for which neighbour should we try to find
778 try_alternative_plugins (struct NeighbourList *neighbour)
780 struct ReadyList *rl;
782 if ((neighbour->plugins != NULL) &&
783 (neighbour->retry_plugins_time.value >
784 GNUNET_TIME_absolute_get ().value))
785 return; /* don't try right now */
786 neighbour->retry_plugins_time
787 = GNUNET_TIME_relative_to_absolute (PLUGIN_RETRY_FREQUENCY);
789 rl = neighbour->plugins;
792 if (rl->connect_attempts > 0)
793 rl->connect_attempts--; /* amnesty */
801 * Check the ready list for the given neighbour and
802 * if a plugin is ready for transmission (and if we
803 * have a message), do so!
805 * @param neighbour target peer for which to check the plugins
807 static void try_transmission_to_peer (struct NeighbourList *neighbour);
811 * The peer specified by the given neighbour has timed-out. Update
812 * our state and do the necessary notifications. Also notifies
813 * our clients that the neighbour is now officially gone.
815 * @param n the neighbour list entry for the peer
818 disconnect_neighbour (struct NeighbourList *n);
822 * Function called by the GNUNET_TRANSPORT_TransmitFunction
823 * upon "completion" of a send request. This tells the API
824 * that it is now legal to send another message to the given
827 * @param cls closure, identifies the entry on the
828 * message queue that was transmitted and the
829 * client responsible for queueing the message
830 * @param rl identifies plugin used for the transmission for
831 * this neighbour; needs to be re-enabled for
832 * future transmissions
833 * @param target the peer receiving the message
834 * @param result GNUNET_OK on success, if the transmission
835 * failed, we should not tell the client to transmit
839 transmit_send_continuation (void *cls,
840 struct ReadyList *rl,
841 const struct GNUNET_PeerIdentity *target,
844 struct MessageQueue *mq = cls;
845 struct SendOkMessage send_ok_msg;
846 struct NeighbourList *n;
848 GNUNET_assert (mq != NULL);
850 GNUNET_assert (n != NULL);
852 memcmp (&n->id, target,
853 sizeof (struct GNUNET_PeerIdentity)));
857 while ((rl != NULL) && (rl->plugin != mq->plugin))
859 GNUNET_assert (rl != NULL);
861 if (result == GNUNET_OK)
863 rl->timeout = GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT);
867 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
868 "Transmission to peer `%s' failed, marking connection as down.\n",
870 rl->connected = GNUNET_NO;
872 if (!mq->internal_msg)
873 rl->transmit_ready = GNUNET_YES;
874 if (mq->client != NULL)
876 send_ok_msg.header.size = htons (sizeof (send_ok_msg));
877 send_ok_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK);
878 send_ok_msg.success = htonl (result);
879 send_ok_msg.peer = n->id;
880 transmit_to_client (mq->client, &send_ok_msg.header, GNUNET_NO);
882 GNUNET_free (mq->message);
884 /* one plugin just became ready again, try transmitting
885 another message (if available) */
886 if (result == GNUNET_OK)
887 try_transmission_to_peer (n);
889 disconnect_neighbour (n);
894 * Check the ready list for the given neighbour and
895 * if a plugin is ready for transmission (and if we
896 * have a message), do so!
899 try_transmission_to_peer (struct NeighbourList *neighbour)
901 struct ReadyList *pos;
902 struct GNUNET_TIME_Relative min_latency;
903 struct ReadyList *rl;
904 struct MessageQueue *mq;
905 struct GNUNET_TIME_Absolute now;
907 if (neighbour->messages == NULL)
908 return; /* nothing to do */
909 try_alternative_plugins (neighbour);
910 min_latency = GNUNET_TIME_UNIT_FOREVER_REL;
912 mq = neighbour->messages;
913 now = GNUNET_TIME_absolute_get ();
914 pos = neighbour->plugins;
917 /* set plugins that are inactive for a long time back to disconnected */
918 if ((pos->timeout.value < now.value) && (pos->connected == GNUNET_YES))
921 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
922 "Marking long-time inactive connection to `%4s' as down.\n",
923 GNUNET_i2s (&neighbour->id));
925 pos->connected = GNUNET_NO;
927 if (((GNUNET_YES == pos->transmit_ready) ||
928 (mq->internal_msg)) &&
929 (pos->connect_attempts < MAX_CONNECT_RETRY) &&
930 ((rl == NULL) || (min_latency.value > pos->latency.value)))
933 min_latency = pos->latency;
940 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
941 "No plugin ready to transmit message\n");
943 return; /* nobody ready */
945 if (GNUNET_NO == rl->connected)
947 rl->connect_attempts++;
948 rl->connected = GNUNET_YES;
950 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
951 "Establishing fresh connection with `%4s' via plugin `%s'\n",
952 GNUNET_i2s (&neighbour->id), rl->plugin->short_name);
955 neighbour->messages = mq->next;
956 mq->plugin = rl->plugin;
957 if (!mq->internal_msg)
958 rl->transmit_ready = GNUNET_NO;
960 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
961 "Giving message of type `%u' for `%4s' to plugin `%s'\n",
962 ntohs (mq->message->type),
963 GNUNET_i2s (&neighbour->id), rl->plugin->short_name);
966 = rl->plugin->api->send (rl->plugin->api->cls,
972 GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
973 &transmit_send_continuation, mq);
978 * Send the specified message to the specified peer.
980 * @param client source of the transmission request (can be NULL)
981 * @param priority how important is the message
982 * @param msg message to send
983 * @param is_internal is this an internal message
984 * @param neighbour handle to the neighbour for transmission
987 transmit_to_peer (struct TransportClient *client,
988 unsigned int priority,
989 const struct GNUNET_MessageHeader *msg,
990 int is_internal, struct NeighbourList *neighbour)
992 struct MessageQueue *mq;
993 struct MessageQueue *mqe;
994 struct GNUNET_MessageHeader *m;
997 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
998 _("Sending message of type %u to peer `%4s'\n"),
999 ntohs (msg->type), GNUNET_i2s (&neighbour->id));
1003 /* check for duplicate submission */
1004 mq = neighbour->messages;
1007 if (mq->client == client)
1009 /* client transmitted to same peer twice
1010 before getting SendOk! */
1017 mq = GNUNET_malloc (sizeof (struct MessageQueue));
1018 mq->client = client;
1019 m = GNUNET_malloc (ntohs (msg->size));
1020 memcpy (m, msg, ntohs (msg->size));
1022 mq->neighbour = neighbour;
1023 mq->internal_msg = is_internal;
1024 mq->priority = priority;
1027 mqe = neighbour->messages;
1029 while (mqe->next != NULL)
1034 neighbour->messages = mq;
1035 try_transmission_to_peer (neighbour);
1048 struct GeneratorContext
1050 struct TransportPlugin *plug_pos;
1051 struct AddressList *addr_pos;
1052 struct GNUNET_TIME_Absolute expiration;
1060 address_generator (void *cls, size_t max, void *buf)
1062 struct GeneratorContext *gc = cls;
1065 while ((gc->addr_pos == NULL) && (gc->plug_pos != NULL))
1067 gc->plug_pos = gc->plug_pos->next;
1068 gc->addr_pos = (gc->plug_pos != NULL) ? gc->plug_pos->addresses : NULL;
1070 if (NULL == gc->plug_pos)
1072 ret = GNUNET_HELLO_add_address (gc->plug_pos->short_name,
1075 gc->addr_pos->addrlen, buf, max);
1076 gc->addr_pos = gc->addr_pos->next;
1082 * Construct our HELLO message from all of the addresses of
1083 * all of the transports.
1088 struct GNUNET_HELLO_Message *hello;
1089 struct TransportClient *cpos;
1090 struct NeighbourList *npos;
1091 struct GeneratorContext gc;
1094 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1095 "Refreshing my `%s'\n",
1098 gc.plug_pos = plugins;
1099 gc.addr_pos = plugins != NULL ? plugins->addresses : NULL;
1100 gc.expiration = GNUNET_TIME_relative_to_absolute (HELLO_ADDRESS_EXPIRATION);
1101 hello = GNUNET_HELLO_create (&my_public_key, &address_generator, &gc);
1103 while (cpos != NULL)
1105 transmit_to_client (cpos,
1106 (const struct GNUNET_MessageHeader *) hello,
1111 GNUNET_free_non_null (our_hello);
1113 our_hello_version++;
1115 while (npos != NULL)
1118 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1119 "Transmitting updated `%s' to neighbour `%4s'\n",
1121 GNUNET_i2s(&npos->id));
1123 transmit_to_peer (NULL, 0,
1124 (const struct GNUNET_MessageHeader *) our_hello,
1132 * Task used to clean up expired addresses for a plugin.
1134 * @param cls closure
1138 expire_address_task (void *cls,
1139 const struct GNUNET_SCHEDULER_TaskContext *tc);
1143 * Update the list of addresses for this plugin,
1144 * expiring those that are past their expiration date.
1146 * @param plugin addresses of which plugin should be recomputed?
1147 * @param fresh set to GNUNET_YES if a new address was added
1148 * and we need to regenerate the HELLO even if nobody
1152 update_addresses (struct TransportPlugin *plugin, int fresh)
1154 struct GNUNET_TIME_Relative min_remaining;
1155 struct GNUNET_TIME_Relative remaining;
1156 struct GNUNET_TIME_Absolute now;
1157 struct AddressList *pos;
1158 struct AddressList *prev;
1159 struct AddressList *next;
1162 if (plugin->address_update_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
1163 GNUNET_SCHEDULER_cancel (plugin->env.sched, plugin->address_update_task);
1164 plugin->address_update_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
1165 now = GNUNET_TIME_absolute_get ();
1166 min_remaining = GNUNET_TIME_UNIT_FOREVER_REL;
1167 expired = GNUNET_NO;
1169 pos = plugin->addresses;
1173 if (pos->expires.value < now.value)
1175 expired = GNUNET_YES;
1177 plugin->addresses = pos->next;
1179 prev->next = pos->next;
1184 remaining = GNUNET_TIME_absolute_get_remaining (pos->expires);
1185 if (remaining.value < min_remaining.value)
1186 min_remaining = remaining;
1192 if (expired || fresh)
1194 if (min_remaining.value < GNUNET_TIME_UNIT_FOREVER_REL.value)
1195 plugin->address_update_task
1196 = GNUNET_SCHEDULER_add_delayed (plugin->env.sched,
1198 GNUNET_SCHEDULER_PRIORITY_IDLE,
1199 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
1201 &expire_address_task, plugin);
1207 * Task used to clean up expired addresses for a plugin.
1209 * @param cls closure
1213 expire_address_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1215 struct TransportPlugin *plugin = cls;
1216 plugin->address_update_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
1217 update_addresses (plugin, GNUNET_NO);
1222 * Function that must be called by each plugin to notify the
1223 * transport service about the addresses under which the transport
1224 * provided by the plugin can be reached.
1226 * @param cls closure
1227 * @param name name of the transport that generated the address
1228 * @param addr one of the addresses of the host, NULL for the last address
1229 * the specific address format depends on the transport
1230 * @param addrlen length of the address
1231 * @param expires when should this address automatically expire?
1234 plugin_env_notify_address (void *cls,
1238 struct GNUNET_TIME_Relative expires)
1240 struct TransportPlugin *p = cls;
1241 struct AddressList *al;
1242 struct GNUNET_TIME_Absolute abex;
1244 abex = GNUNET_TIME_relative_to_absolute (expires);
1245 GNUNET_assert (p == find_transport (name));
1250 if ((addrlen == al->addrlen) && (0 == memcmp (addr, &al[1], addrlen)))
1252 if (al->expires.value < abex.value)
1259 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1260 "Plugin `%s' informs us about a new address `%s'\n", name,
1261 GNUNET_a2s(addr, addrlen));
1263 al = GNUNET_malloc (sizeof (struct AddressList) + addrlen);
1265 al->next = p->addresses;
1268 al->addrlen = addrlen;
1269 memcpy (&al[1], addr, addrlen);
1270 update_addresses (p, GNUNET_YES);
1277 struct LookupHelloContext
1279 GNUNET_TRANSPORT_AddressCallback iterator;
1289 lookup_address_callback (void *cls,
1291 struct GNUNET_TIME_Absolute expiration,
1292 const void *addr, size_t addrlen)
1294 struct LookupHelloContext *lhc = cls;
1295 lhc->iterator (lhc->iterator_cls, tname, addr, addrlen);
1304 lookup_hello_callback (void *cls,
1305 const struct GNUNET_PeerIdentity *peer,
1306 const struct GNUNET_HELLO_Message *h, uint32_t trust)
1308 struct LookupHelloContext *lhc = cls;
1312 lhc->iterator (lhc->iterator_cls, NULL, NULL, 0);
1318 GNUNET_HELLO_iterate_addresses (h,
1319 GNUNET_NO, &lookup_address_callback, lhc);
1324 * Function that allows a transport to query the known
1325 * network addresses for a given peer.
1327 * @param cls closure
1328 * @param timeout after how long should we time out?
1329 * @param target which peer are we looking for?
1330 * @param iter function to call for each known address
1331 * @param iter_cls closure for iter
1334 plugin_env_lookup_address (void *cls,
1335 struct GNUNET_TIME_Relative timeout,
1336 const struct GNUNET_PeerIdentity *target,
1337 GNUNET_TRANSPORT_AddressCallback iter,
1340 struct LookupHelloContext *lhc;
1342 lhc = GNUNET_malloc (sizeof (struct LookupHelloContext));
1343 lhc->iterator = iter;
1344 lhc->iterator_cls = iter_cls;
1345 GNUNET_PEERINFO_for_all (cfg,
1347 target, 0, timeout, &lookup_hello_callback, &lhc);
1352 * Notify all of our clients about a peer connecting.
1355 notify_clients_connect (const struct GNUNET_PeerIdentity *peer,
1356 struct GNUNET_TIME_Relative latency)
1358 struct ConnectInfoMessage cim;
1359 struct TransportClient *cpos;
1362 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1363 "Informing clients about peer `%4s' connecting to us\n",
1366 cim.header.size = htons (sizeof (struct ConnectInfoMessage));
1367 cim.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT);
1368 cim.quota_out = htonl (GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT / (60*1000));
1369 cim.latency = GNUNET_TIME_relative_hton (latency);
1370 memcpy (&cim.id, peer, sizeof (struct GNUNET_PeerIdentity));
1372 while (cpos != NULL)
1374 transmit_to_client (cpos, &cim.header, GNUNET_NO);
1381 * Notify all of our clients about a peer disconnecting.
1384 notify_clients_disconnect (const struct GNUNET_PeerIdentity *peer)
1386 struct DisconnectInfoMessage dim;
1387 struct TransportClient *cpos;
1390 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1391 "Informing clients about peer `%4s' disconnecting\n",
1394 dim.header.size = htons (sizeof (struct DisconnectInfoMessage));
1395 dim.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT);
1396 dim.reserved = htonl (0);
1397 memcpy (&dim.peer, peer, sizeof (struct GNUNET_PeerIdentity));
1399 while (cpos != NULL)
1401 transmit_to_client (cpos, &dim.header, GNUNET_NO);
1408 * Copy any validated addresses to buf.
1410 * @return 0 once all addresses have been
1414 list_validated_addresses (void *cls, size_t max, void *buf)
1416 struct ValidationAddress **va = cls;
1419 while ((NULL != *va) && ((*va)->ok != GNUNET_YES))
1423 ret = GNUNET_HELLO_add_address ((*va)->transport_name,
1425 &(*va)[1], (*va)->addr_len, buf, max);
1432 * HELLO validation cleanup task.
1435 cleanup_validation (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1437 struct ValidationAddress *va;
1438 struct ValidationList *pos;
1439 struct ValidationList *prev;
1440 struct GNUNET_TIME_Absolute now;
1441 struct GNUNET_HELLO_Message *hello;
1442 struct GNUNET_PeerIdentity pid;
1443 struct NeighbourList *n;
1446 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1447 "HELLO validation cleanup background task running...\n");
1449 now = GNUNET_TIME_absolute_get ();
1451 pos = pending_validations;
1454 if (pos->timeout.value < now.value)
1457 pending_validations = pos->next;
1459 prev->next = pos->next;
1460 va = pos->addresses;
1461 hello = GNUNET_HELLO_create (&pos->publicKey,
1462 &list_validated_addresses, &va);
1463 GNUNET_CRYPTO_hash (&pos->publicKey,
1465 GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
1468 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1469 "Creating persistent `%s' message for peer `%4s' based on confirmed addresses.\n",
1470 "HELLO", GNUNET_i2s (&pid));
1472 GNUNET_PEERINFO_add_peer (cfg, sched, &pid, hello);
1473 n = find_neighbour (&pid);
1475 try_transmission_to_peer (n);
1476 GNUNET_free (hello);
1477 while (NULL != (va = pos->addresses))
1479 pos->addresses = va->next;
1480 GNUNET_free (va->transport_name);
1485 pos = pending_validations;
1494 /* finally, reschedule cleanup if needed; list is
1495 ordered by timeout, so we need the last element... */
1496 pos = pending_validations;
1497 while ((pos != NULL) && (pos->next != NULL))
1500 GNUNET_SCHEDULER_add_delayed (sched,
1502 GNUNET_SCHEDULER_PRIORITY_IDLE,
1503 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
1504 GNUNET_TIME_absolute_get_remaining
1505 (pos->timeout), &cleanup_validation, NULL);
1512 * Function that will be called if we receive a validation
1513 * of an address challenge that we transmitted to another
1514 * peer. Note that the validation should only be considered
1515 * acceptable if the challenge matches AND if the sender
1516 * address is at least a plausible address for this peer
1517 * (otherwise we may be seeing a MiM attack).
1519 * @param cls closure
1520 * @param name name of the transport that generated the address
1521 * @param peer who responded to our challenge
1522 * @param challenge the challenge number we presumably used
1523 * @param sender_addr string describing our sender address (as observed
1524 * by the other peer in human-readable format)
1527 plugin_env_notify_validation (void *cls,
1529 const struct GNUNET_PeerIdentity *peer,
1531 const char *sender_addr)
1535 struct ValidationList *pos;
1536 struct ValidationAddress *va;
1537 struct GNUNET_PeerIdentity id;
1539 pos = pending_validations;
1542 GNUNET_CRYPTO_hash (&pos->publicKey,
1544 GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
1547 memcmp (peer, &id, sizeof (struct GNUNET_PeerIdentity)))
1553 /* TODO: call statistics (unmatched PONG) */
1554 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1556 ("Received validation response but have no record of any validation request for `%4s'. Ignoring.\n"),
1560 all_done = GNUNET_YES;
1561 matched = GNUNET_NO;
1562 va = pos->addresses;
1565 if (va->challenge == challenge)
1568 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1569 "Confirmed validity of peer address.\n");
1571 GNUNET_log (GNUNET_ERROR_TYPE_INFO | GNUNET_ERROR_TYPE_BULK,
1572 _("Another peer saw us using the address `%s' via `%s'. If this is not plausible, this address should be listed in the configuration as implausible to avoid MiM attacks.\n"),
1575 va->ok = GNUNET_YES;
1577 GNUNET_TIME_relative_to_absolute (HELLO_ADDRESS_EXPIRATION);
1578 matched = GNUNET_YES;
1580 if (va->ok != GNUNET_YES)
1581 all_done = GNUNET_NO;
1584 if (GNUNET_NO == matched)
1586 /* TODO: call statistics (unmatched PONG) */
1587 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1589 ("Received `%s' message but have no record of a matching `%s' message. Ignoring.\n"),
1592 if (GNUNET_YES == all_done)
1594 pos->timeout.value = 0;
1595 GNUNET_SCHEDULER_add_delayed (sched,
1597 GNUNET_SCHEDULER_PRIORITY_IDLE,
1598 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
1599 GNUNET_TIME_UNIT_ZERO,
1600 &cleanup_validation, NULL);
1605 struct CheckHelloValidatedContext
1608 * Plugin for which we are validating.
1610 struct TransportPlugin *plugin;
1613 * Hello that we are validating.
1615 struct GNUNET_HELLO_Message *hello;
1618 * Validation list being build.
1620 struct ValidationList *e;
1626 * Append the given address to the list of entries
1627 * that need to be validated.
1630 run_validation (void *cls,
1632 struct GNUNET_TIME_Absolute expiration,
1633 const void *addr, size_t addrlen)
1635 struct ValidationList *e = cls;
1636 struct TransportPlugin *tp;
1637 struct ValidationAddress *va;
1638 struct GNUNET_PeerIdentity id;
1640 tp = find_transport (tname);
1643 GNUNET_log (GNUNET_ERROR_TYPE_INFO |
1644 GNUNET_ERROR_TYPE_BULK,
1646 ("Transport `%s' not loaded, will not try to validate peer address using this transport.\n"),
1650 GNUNET_CRYPTO_hash (&e->publicKey,
1652 GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
1654 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1655 "Scheduling validation of address `%s' via `%s' for `%4s'\n",
1656 GNUNET_a2s(addr, addrlen),
1660 va = GNUNET_malloc (sizeof (struct ValidationAddress) + addrlen);
1661 va->next = e->addresses;
1663 va->transport_name = GNUNET_strdup (tname);
1664 va->addr_len = addrlen;
1665 va->challenge = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1667 memcpy (&va[1], addr, addrlen);
1673 * Check if addresses in validated hello "h" overlap with
1674 * those in "chvc->hello" and update "chvc->hello" accordingly,
1675 * removing those addresses that have already been validated.
1678 check_hello_validated (void *cls,
1679 const struct GNUNET_PeerIdentity *peer,
1680 const struct GNUNET_HELLO_Message *h,
1683 struct CheckHelloValidatedContext *chvc = cls;
1684 struct ValidationAddress *va;
1685 struct TransportPlugin *tp;
1687 struct GNUNET_PeerIdentity apeer;
1689 first_call = GNUNET_NO;
1690 if (chvc->e == NULL)
1692 first_call = GNUNET_YES;
1693 chvc->e = GNUNET_malloc (sizeof (struct ValidationList));
1694 GNUNET_assert (GNUNET_OK ==
1695 GNUNET_HELLO_get_key (h != NULL ? h : chvc->hello,
1696 &chvc->e->publicKey));
1698 GNUNET_TIME_relative_to_absolute (HELLO_VERIFICATION_TIMEOUT);
1699 chvc->e->next = pending_validations;
1700 pending_validations = chvc->e;
1704 GNUNET_HELLO_iterate_new_addresses (chvc->hello,
1706 GNUNET_TIME_absolute_get (),
1707 &run_validation, chvc->e);
1709 else if (GNUNET_YES == first_call)
1711 /* no existing HELLO, all addresses are new */
1712 GNUNET_HELLO_iterate_addresses (chvc->hello,
1713 GNUNET_NO, &run_validation, chvc->e);
1716 return; /* wait for next call */
1717 /* finally, transmit validation attempts */
1718 GNUNET_assert (GNUNET_OK ==
1719 GNUNET_HELLO_get_id (chvc->hello,
1721 va = chvc->e->addresses;
1725 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1726 "Establishing `%s' connection to validate `%s' of `%4s'\n",
1729 GNUNET_i2s (&apeer));
1731 tp = find_transport (va->transport_name);
1732 GNUNET_assert (tp != NULL);
1734 tp->api->validate (tp->api->cls,
1737 HELLO_VERIFICATION_TIMEOUT,
1740 va->ok = GNUNET_SYSERR;
1743 if (chvc->e->next == NULL)
1744 GNUNET_SCHEDULER_add_delayed (sched,
1746 GNUNET_SCHEDULER_PRIORITY_IDLE,
1747 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
1748 GNUNET_TIME_absolute_get_remaining
1749 (chvc->e->timeout), &cleanup_validation,
1756 * Process HELLO-message.
1758 * @param plugin transport involved, may be NULL
1759 * @param message the actual message
1760 * @return GNUNET_OK if the HELLO was well-formed, GNUNET_SYSERR otherwise
1763 process_hello (struct TransportPlugin *plugin,
1764 const struct GNUNET_MessageHeader *message)
1766 struct ValidationList *e;
1768 struct GNUNET_PeerIdentity target;
1769 const struct GNUNET_HELLO_Message *hello;
1770 struct CheckHelloValidatedContext *chvc;
1771 struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded publicKey;
1773 hsize = ntohs (message->size);
1774 if ((ntohs (message->type) != GNUNET_MESSAGE_TYPE_HELLO) ||
1775 (hsize < sizeof (struct GNUNET_MessageHeader)))
1778 return GNUNET_SYSERR;
1780 /* first, check if load is too high */
1781 if (GNUNET_OS_load_cpu_get (cfg) > 100)
1783 /* TODO: call to stats? */
1786 hello = (const struct GNUNET_HELLO_Message *) message;
1787 if (GNUNET_OK != GNUNET_HELLO_get_key (hello, &publicKey))
1789 GNUNET_break_op (0);
1790 return GNUNET_SYSERR;
1792 GNUNET_CRYPTO_hash (&publicKey,
1793 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
1794 &target.hashPubKey);
1796 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1797 "Processing `%s' message for `%4s'\n",
1798 "HELLO", GNUNET_i2s (&target));
1800 /* check if a HELLO for this peer is already on the validation list */
1801 e = pending_validations;
1804 if (0 == memcmp (&e->publicKey,
1807 GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded)))
1809 /* TODO: call to stats? */
1811 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1812 "`%s' message for peer `%4s' is already pending; ignoring new message\n",
1813 "HELLO", GNUNET_i2s (&target));
1819 chvc = GNUNET_malloc (sizeof (struct CheckHelloValidatedContext) + hsize);
1820 chvc->plugin = plugin;
1821 chvc->hello = (struct GNUNET_HELLO_Message *) &chvc[1];
1822 memcpy (chvc->hello, hello, hsize);
1823 /* finally, check if HELLO was previously validated
1824 (continuation will then schedule actual validation) */
1825 GNUNET_PEERINFO_for_all (cfg,
1829 HELLO_VERIFICATION_TIMEOUT,
1830 &check_hello_validated, chvc);
1836 * The peer specified by the given neighbour has timed-out. Update
1837 * our state and do the necessary notifications. Also notifies
1838 * our clients that the neighbour is now officially gone.
1840 * @param n the neighbour list entry for the peer
1843 disconnect_neighbour (struct NeighbourList *n)
1845 struct ReadyList *rpos;
1846 struct NeighbourList *npos;
1847 struct NeighbourList *nprev;
1848 struct MessageQueue *mq;
1851 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1852 "Disconnecting from `%4s'\n",
1853 GNUNET_i2s(&n->id));
1855 /* remove n from neighbours list */
1858 while ((npos != NULL) && (npos != n))
1863 GNUNET_assert (npos != NULL);
1865 neighbours = n->next;
1867 nprev->next = n->next;
1869 /* notify all clients about disconnect */
1870 notify_clients_disconnect (&n->id);
1872 /* clean up all plugins, cancel connections & pending transmissions */
1873 while (NULL != (rpos = n->plugins))
1875 n->plugins = rpos->next;
1876 GNUNET_assert (rpos->neighbour == n);
1877 rpos->plugin->api->cancel (rpos->plugin->api->cls,
1878 rpos->plugin_handle, rpos, &n->id);
1882 /* free all messages on the queue */
1883 while (NULL != (mq = n->messages))
1885 n->messages = mq->next;
1886 GNUNET_assert (mq->neighbour == n);
1890 /* finally, free n itself */
1896 * Add an entry for each of our transport plugins
1897 * (that are able to send) to the list of plugins
1898 * for this neighbour.
1900 * @param neighbour to initialize
1903 add_plugins (struct NeighbourList *neighbour)
1905 struct TransportPlugin *tp;
1906 struct ReadyList *rl;
1908 neighbour->retry_plugins_time
1909 = GNUNET_TIME_relative_to_absolute (PLUGIN_RETRY_FREQUENCY);
1913 if (tp->api->send != NULL)
1915 rl = GNUNET_malloc (sizeof (struct ReadyList));
1916 rl->next = neighbour->plugins;
1917 neighbour->plugins = rl;
1919 rl->neighbour = neighbour;
1920 rl->transmit_ready = GNUNET_YES;
1928 neighbour_timeout_task (void *cls,
1929 const struct GNUNET_SCHEDULER_TaskContext *tc)
1931 struct NeighbourList *n = cls;
1934 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1935 "Neighbour `%4s' has timed out!\n",
1936 GNUNET_i2s(&n->id));
1938 n->timeout_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
1939 disconnect_neighbour (n);
1944 * Create a fresh entry in our neighbour list for the given peer.
1945 * Will try to transmit our current HELLO to the new neighbour. Also
1946 * notifies our clients about the new "connection".
1948 * @param peer the peer for which we create the entry
1949 * @return the new neighbour list entry
1951 static struct NeighbourList *
1952 setup_new_neighbour (const struct GNUNET_PeerIdentity *peer)
1954 struct NeighbourList *n;
1957 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1958 "Setting up new neighbour `%4s', sending our HELLO to introduce ourselves\n",
1961 GNUNET_assert (our_hello != NULL);
1962 n = GNUNET_malloc (sizeof (struct NeighbourList));
1963 n->next = neighbours;
1966 n->last_quota_update = GNUNET_TIME_absolute_get ();
1968 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT);
1969 n->quota_in = (GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT + 59999) / (60 * 1000);
1971 n->timeout_task = GNUNET_SCHEDULER_add_delayed (sched,
1973 GNUNET_SCHEDULER_PRIORITY_IDLE,
1974 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
1975 GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
1976 &neighbour_timeout_task, n);
1977 transmit_to_peer (NULL, 0,
1978 (const struct GNUNET_MessageHeader *) our_hello,
1980 notify_clients_connect (peer, GNUNET_TIME_UNIT_FOREVER_REL);
1986 * Function called by the plugin for each received message.
1987 * Update data volumes, possibly notify plugins about
1988 * reducing the rate at which they read from the socket
1989 * and generally forward to our receive callback.
1991 * @param plugin_context value to pass to this plugin
1992 * to respond to the given peer (use is optional,
1993 * but may speed up processing)
1994 * @param service_context value passed to the transport-service
1995 * to identify the neighbour; will be NULL on the first
1996 * call for a given peer
1997 * @param latency estimated latency for communicating with the
1999 * @param peer (claimed) identity of the other peer
2000 * @param message the message, NULL if peer was disconnected
2001 * @return the new service_context that the plugin should use
2002 * for future receive calls for messages from this
2005 static struct ReadyList *
2006 plugin_env_receive (void *cls,
2007 void *plugin_context,
2008 struct ReadyList *service_context,
2009 struct GNUNET_TIME_Relative latency,
2010 const struct GNUNET_PeerIdentity *peer,
2011 const struct GNUNET_MessageHeader *message)
2013 const struct GNUNET_MessageHeader ack = {
2014 htons (sizeof (struct GNUNET_MessageHeader)),
2015 htons (GNUNET_MESSAGE_TYPE_TRANSPORT_ACK)
2017 struct TransportPlugin *plugin = cls;
2018 struct TransportClient *cpos;
2019 struct InboundMessage *im;
2021 struct NeighbourList *n;
2023 if (service_context != NULL)
2025 n = service_context->neighbour;
2026 GNUNET_assert (n != NULL);
2030 n = find_neighbour (peer);
2033 if (message == NULL)
2034 return NULL; /* disconnect of peer already marked down */
2035 n = setup_new_neighbour (peer);
2037 service_context = n->plugins;
2038 while ((service_context != NULL) && (plugin != service_context->plugin))
2039 service_context = service_context->next;
2040 GNUNET_assert ((plugin->api->send == NULL) ||
2041 (service_context != NULL));
2043 if (message == NULL)
2045 if ((service_context != NULL) &&
2046 (service_context->plugin_handle == plugin_context))
2048 service_context->connected = GNUNET_NO;
2049 service_context->plugin_handle = NULL;
2051 /* TODO: call stats */
2055 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
2056 "Processing message of type `%u' received by plugin...\n",
2057 ntohs (message->type));
2059 if (service_context != NULL)
2061 if (service_context->connected == GNUNET_NO)
2063 service_context->connected = GNUNET_YES;
2064 service_context->transmit_ready = GNUNET_YES;
2065 service_context->connect_attempts++;
2067 service_context->timeout
2068 = GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT);
2069 service_context->plugin_handle = plugin_context;
2070 service_context->latency = latency;
2072 /* update traffic received amount ... */
2073 msize = ntohs (message->size);
2074 n->last_received += msize;
2075 GNUNET_SCHEDULER_cancel (sched, n->timeout_task);
2077 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT);
2079 GNUNET_SCHEDULER_add_delayed (sched, GNUNET_NO,
2080 GNUNET_SCHEDULER_PRIORITY_IDLE,
2081 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
2082 GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
2083 &neighbour_timeout_task, n);
2085 if (n->quota_violation_count > QUOTA_VIOLATION_DROP_THRESHOLD)
2087 /* dropping message due to frequent inbound volume violations! */
2088 GNUNET_log (GNUNET_ERROR_TYPE_WARNING |
2089 GNUNET_ERROR_TYPE_BULK,
2091 ("Dropping incoming message due to repeated bandwidth quota violations.\n"));
2092 /* TODO: call stats */
2093 GNUNET_assert (NULL != service_context->neighbour);
2094 return service_context;
2096 switch (ntohs (message->type))
2098 case GNUNET_MESSAGE_TYPE_HELLO:
2100 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2101 "Receiving `%s' message from `%4s'.\n", "HELLO",
2104 process_hello (plugin, message);
2106 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2107 "Sending `%s' message to connecting peer `%4s'.\n", "ACK",
2110 transmit_to_peer (NULL, 0, &ack, GNUNET_YES, n);
2112 case GNUNET_MESSAGE_TYPE_TRANSPORT_ACK:
2113 n->saw_ack = GNUNET_YES;
2114 /* intentional fall-through! */
2117 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2118 "Received message of type %u from `%4s', sending to all clients.\n",
2119 ntohs (message->type),
2122 /* transmit message to all clients */
2123 im = GNUNET_malloc (sizeof (struct InboundMessage) + msize);
2124 im->header.size = htons (sizeof (struct InboundMessage) + msize);
2125 im->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_RECV);
2126 im->latency = GNUNET_TIME_relative_hton (latency);
2128 memcpy (&im[1], message, msize);
2131 while (cpos != NULL)
2133 transmit_to_client (cpos, &im->header, GNUNET_YES);
2138 GNUNET_assert (NULL != service_context->neighbour);
2139 return service_context;
2144 * Handle START-message. This is the first message sent to us
2145 * by any client which causes us to add it to our list.
2147 * @param cls closure (always NULL)
2148 * @param client identification of the client
2149 * @param message the actual message
2152 handle_start (void *cls,
2153 struct GNUNET_SERVER_Client *client,
2154 const struct GNUNET_MessageHeader *message)
2156 struct TransportClient *c;
2157 struct ConnectInfoMessage cim;
2158 struct NeighbourList *n;
2159 struct InboundMessage *im;
2160 struct GNUNET_MessageHeader *ack;
2163 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2164 "Received `%s' request from client\n", "START");
2169 if (c->client == client)
2171 /* client already on our list! */
2173 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
2178 c = GNUNET_malloc (sizeof (struct TransportClient));
2182 if (our_hello != NULL)
2185 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2186 "Sending our own HELLO to new client\n");
2188 transmit_to_client (c,
2189 (const struct GNUNET_MessageHeader *) our_hello,
2191 /* tell new client about all existing connections */
2192 cim.header.size = htons (sizeof (struct ConnectInfoMessage));
2193 cim.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT);
2194 cim.quota_out = htonl (GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT / (60 * 1000));
2195 cim.latency = GNUNET_TIME_relative_hton (GNUNET_TIME_UNIT_ZERO); /* FIXME? */
2196 im = GNUNET_malloc (sizeof (struct InboundMessage) +
2197 sizeof (struct GNUNET_MessageHeader));
2198 im->header.size = htons (sizeof (struct InboundMessage) +
2199 sizeof (struct GNUNET_MessageHeader));
2200 im->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_RECV);
2201 im->latency = GNUNET_TIME_relative_hton (GNUNET_TIME_UNIT_ZERO); /* FIXME? */
2202 ack = (struct GNUNET_MessageHeader *) &im[1];
2203 ack->size = htons (sizeof (struct GNUNET_MessageHeader));
2204 ack->type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_ACK);
2205 for (n = neighbours; n != NULL; n = n->next)
2208 transmit_to_client (c, &cim.header, GNUNET_NO);
2212 transmit_to_client (c, &im->header, GNUNET_NO);
2217 GNUNET_SERVER_receive_done (client, GNUNET_OK);
2222 * Handle HELLO-message.
2224 * @param cls closure (always NULL)
2225 * @param client identification of the client
2226 * @param message the actual message
2229 handle_hello (void *cls,
2230 struct GNUNET_SERVER_Client *client,
2231 const struct GNUNET_MessageHeader *message)
2236 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2237 "Received `%s' request from client\n", "HELLO");
2239 ret = process_hello (NULL, message);
2240 GNUNET_SERVER_receive_done (client, ret);
2245 * Handle SEND-message.
2247 * @param cls closure (always NULL)
2248 * @param client identification of the client
2249 * @param message the actual message
2252 handle_send (void *cls,
2253 struct GNUNET_SERVER_Client *client,
2254 const struct GNUNET_MessageHeader *message)
2256 struct TransportClient *tc;
2257 struct NeighbourList *n;
2258 const struct OutboundMessage *obm;
2259 const struct GNUNET_MessageHeader *obmm;
2263 size = ntohs (message->size);
2265 sizeof (struct OutboundMessage) + sizeof (struct GNUNET_MessageHeader))
2268 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
2271 obm = (const struct OutboundMessage *) message;
2273 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2274 "Received `%s' request from client with target `%4s'\n",
2275 "SEND", GNUNET_i2s (&obm->peer));
2277 obmm = (const struct GNUNET_MessageHeader *) &obm[1];
2278 msize = ntohs (obmm->size);
2279 if (size != msize + sizeof (struct OutboundMessage))
2282 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
2285 n = find_neighbour (&obm->peer);
2287 n = setup_new_neighbour (&obm->peer);
2289 while ((tc != NULL) && (tc->client != client))
2293 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2294 "Client asked to transmit %u-byte message of type %u to `%4s'\n",
2296 ntohs (obmm->type), GNUNET_i2s (&obm->peer));
2298 transmit_to_peer (tc, ntohl(obm->priority), obmm, GNUNET_NO, n);
2299 GNUNET_SERVER_receive_done (client, GNUNET_OK);
2304 * Handle SET_QUOTA-message.
2306 * @param cls closure (always NULL)
2307 * @param client identification of the client
2308 * @param message the actual message
2311 handle_set_quota (void *cls,
2312 struct GNUNET_SERVER_Client *client,
2313 const struct GNUNET_MessageHeader *message)
2315 const struct QuotaSetMessage *qsm =
2316 (const struct QuotaSetMessage *) message;
2317 struct NeighbourList *n;
2318 struct TransportPlugin *p;
2319 struct ReadyList *rl;
2322 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2323 "Received `%s' request from client for peer `%4s'\n",
2324 "SET_QUOTA", GNUNET_i2s (&qsm->peer));
2326 n = find_neighbour (&qsm->peer);
2329 GNUNET_SERVER_receive_done (client, GNUNET_OK);
2333 if (n->quota_in < ntohl (qsm->quota_in))
2334 n->last_quota_update = GNUNET_TIME_absolute_get ();
2335 n->quota_in = ntohl (qsm->quota_in);
2340 p->api->set_receive_quota (p->api->cls,
2341 &qsm->peer, ntohl (qsm->quota_in));
2344 GNUNET_SERVER_receive_done (client, GNUNET_OK);
2349 * Handle TRY_CONNECT-message.
2351 * @param cls closure (always NULL)
2352 * @param client identification of the client
2353 * @param message the actual message
2356 handle_try_connect (void *cls,
2357 struct GNUNET_SERVER_Client *client,
2358 const struct GNUNET_MessageHeader *message)
2360 const struct TryConnectMessage *tcm;
2362 tcm = (const struct TryConnectMessage *) message;
2364 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2365 "Received `%s' request from client asking to connect to `%4s'\n",
2366 "TRY_CONNECT", GNUNET_i2s (&tcm->peer));
2368 if (NULL == find_neighbour (&tcm->peer))
2369 setup_new_neighbour (&tcm->peer);
2372 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2373 "Client asked to connect to `%4s', but connection already exists\n",
2375 GNUNET_i2s (&tcm->peer));
2377 GNUNET_SERVER_receive_done (client, GNUNET_OK);
2382 * List of handlers for the messages understood by this
2385 static struct GNUNET_SERVER_MessageHandler handlers[] = {
2386 {&handle_start, NULL,
2387 GNUNET_MESSAGE_TYPE_TRANSPORT_START, 0},
2388 {&handle_hello, NULL,
2389 GNUNET_MESSAGE_TYPE_HELLO, 0},
2390 {&handle_send, NULL,
2391 GNUNET_MESSAGE_TYPE_TRANSPORT_SEND, 0},
2392 {&handle_set_quota, NULL,
2393 GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA, sizeof (struct QuotaSetMessage)},
2394 {&handle_try_connect, NULL,
2395 GNUNET_MESSAGE_TYPE_TRANSPORT_TRY_CONNECT,
2396 sizeof (struct TryConnectMessage)},
2402 * Setup the environment for this plugin.
2405 create_environment (struct TransportPlugin *plug)
2407 plug->env.cfg = cfg;
2408 plug->env.sched = sched;
2409 plug->env.my_public_key = &my_public_key;
2410 plug->env.my_private_key = my_private_key;
2411 plug->env.my_identity = &my_identity;
2412 plug->env.cls = plug;
2413 plug->env.receive = &plugin_env_receive;
2414 plug->env.lookup = &plugin_env_lookup_address;
2415 plug->env.notify_address = &plugin_env_notify_address;
2416 plug->env.notify_validation = &plugin_env_notify_validation;
2417 plug->env.default_quota_in = (GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT + 59999) / (60 * 1000);
2418 plug->env.max_connections = max_connect_per_transport;
2423 * Start the specified transport (load the plugin).
2426 start_transport (struct GNUNET_SERVER_Handle *server, const char *name)
2428 struct TransportPlugin *plug;
2431 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2432 _("Loading `%s' transport plugin\n"), name);
2433 GNUNET_asprintf (&libname, "libgnunet_plugin_transport_%s", name);
2434 plug = GNUNET_malloc (sizeof (struct TransportPlugin));
2435 create_environment (plug);
2436 plug->short_name = GNUNET_strdup (name);
2437 plug->lib_name = libname;
2438 plug->next = plugins;
2440 plug->api = GNUNET_PLUGIN_load (libname, &plug->env);
2441 if (plug->api == NULL)
2443 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2444 _("Failed to load transport plugin for `%s'\n"), name);
2445 GNUNET_free (plug->short_name);
2446 plugins = plug->next;
2447 GNUNET_free (libname);
2454 * Called whenever a client is disconnected. Frees our
2455 * resources associated with that client.
2457 * @param cls closure
2458 * @param client identification of the client
2461 client_disconnect_notification (void *cls,
2462 struct GNUNET_SERVER_Client *client)
2464 struct TransportClient *pos;
2465 struct TransportClient *prev;
2466 struct ClientMessageQueueEntry *mqe;
2469 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
2470 "Client disconnected, cleaning up.\n");
2474 while ((pos != NULL) && (pos->client != client))
2481 while (NULL != (mqe = pos->message_queue_head))
2483 pos->message_queue_head = mqe->next;
2486 pos->message_queue_head = NULL;
2488 clients = pos->next;
2490 prev->next = pos->next;
2491 if (GNUNET_YES == pos->tcs_pending)
2501 * Initiate transport service.
2503 * @param cls closure
2504 * @param s scheduler to use
2505 * @param serv the initialized server
2506 * @param c configuration to use
2510 struct GNUNET_SCHEDULER_Handle *s,
2511 struct GNUNET_SERVER_Handle *serv, struct GNUNET_CONFIGURATION_Handle *c)
2516 unsigned long long tneigh;
2521 /* parse configuration */
2523 GNUNET_CONFIGURATION_get_value_number (c,
2528 GNUNET_CONFIGURATION_get_value_filename (c,
2530 "HOSTKEY", &keyfile)))
2532 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2534 ("Transport service is lacking key configuration settings. Exiting.\n"));
2535 GNUNET_SCHEDULER_shutdown (s);
2538 max_connect_per_transport = (uint32_t) tneigh;
2539 my_private_key = GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
2540 GNUNET_free (keyfile);
2541 if (my_private_key == NULL)
2543 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2545 ("Transport service could not access hostkey. Exiting.\n"));
2546 GNUNET_SCHEDULER_shutdown (s);
2549 GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &my_public_key);
2550 GNUNET_CRYPTO_hash (&my_public_key,
2551 sizeof (my_public_key), &my_identity.hashPubKey);
2552 /* setup notification */
2554 GNUNET_SERVER_disconnect_notify (server,
2555 &client_disconnect_notification, NULL);
2556 /* load plugins... */
2559 GNUNET_CONFIGURATION_get_value_string (c,
2560 "TRANSPORT", "PLUGINS", &plugs))
2562 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2563 _("Starting transport plugins `%s'\n"), plugs);
2564 pos = strtok (plugs, " ");
2567 start_transport (server, pos);
2569 pos = strtok (NULL, " ");
2571 GNUNET_free (plugs);
2576 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2577 _("Transport service ready.\n"));
2579 /* process client requests */
2580 GNUNET_SERVER_add_handlers (server, handlers);
2585 * Function called when the service shuts
2586 * down. Unloads our plugins.
2588 * @param cls closure
2589 * @param cfg configuration to use
2592 unload_plugins (void *cls, struct GNUNET_CONFIGURATION_Handle *cfg)
2594 struct TransportPlugin *plug;
2595 struct AddressList *al;
2598 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2599 "Transport service is unloading plugins...\n");
2601 while (NULL != (plug = plugins))
2603 plugins = plug->next;
2604 GNUNET_break (NULL == GNUNET_PLUGIN_unload (plug->lib_name, plug->api));
2605 GNUNET_free (plug->lib_name);
2606 GNUNET_free (plug->short_name);
2607 while (NULL != (al = plug->addresses))
2609 plug->addresses = al->next;
2614 if (my_private_key != NULL)
2615 GNUNET_CRYPTO_rsa_key_free (my_private_key);
2620 * The main function for the transport service.
2622 * @param argc number of arguments from the command line
2623 * @param argv command line arguments
2624 * @return 0 ok, 1 on error
2627 main (int argc, char *const *argv)
2629 return (GNUNET_OK ==
2630 GNUNET_SERVICE_run (argc,
2633 &run, NULL, &unload_plugins, NULL)) ? 0 : 1;
2636 /* end of gnunet-service-transport.c */