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 * Function called by the GNUNET_TRANSPORT_TransmitFunction
812 * upon "completion" of a send request. This tells the API
813 * that it is now legal to send another message to the given
816 * @param cls closure, identifies the entry on the
817 * message queue that was transmitted and the
818 * client responsible for queueing the message
819 * @param rl identifies plugin used for the transmission for
820 * this neighbour; needs to be re-enabled for
821 * future transmissions
822 * @param target the peer receiving the message
823 * @param result GNUNET_OK on success, if the transmission
824 * failed, we should not tell the client to transmit
828 transmit_send_continuation (void *cls,
829 struct ReadyList *rl,
830 const struct GNUNET_PeerIdentity *target,
833 struct MessageQueue *mq = cls;
834 struct SendOkMessage send_ok_msg;
835 struct NeighbourList *n;
837 GNUNET_assert (mq != NULL);
839 GNUNET_assert (n != NULL);
841 memcmp (&n->id, target,
842 sizeof (struct GNUNET_PeerIdentity)));
846 while ((rl != NULL) && (rl->plugin != mq->plugin))
848 GNUNET_assert (rl != NULL);
850 if (result == GNUNET_OK)
852 rl->timeout = GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT);
856 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
857 "Transmission failed, marking connection as down.\n");
858 rl->connected = GNUNET_NO;
860 if (!mq->internal_msg)
861 rl->transmit_ready = GNUNET_YES;
862 if (mq->client != NULL)
864 send_ok_msg.header.size = htons (sizeof (send_ok_msg));
865 send_ok_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_SEND_OK);
866 send_ok_msg.success = htonl (result);
867 send_ok_msg.peer = n->id;
868 transmit_to_client (mq->client, &send_ok_msg.header, GNUNET_NO);
870 GNUNET_free (mq->message);
872 /* one plugin just became ready again, try transmitting
873 another message (if available) */
874 try_transmission_to_peer (n);
879 * Check the ready list for the given neighbour and
880 * if a plugin is ready for transmission (and if we
881 * have a message), do so!
884 try_transmission_to_peer (struct NeighbourList *neighbour)
886 struct ReadyList *pos;
887 struct GNUNET_TIME_Relative min_latency;
888 struct ReadyList *rl;
889 struct MessageQueue *mq;
890 struct GNUNET_TIME_Absolute now;
892 if (neighbour->messages == NULL)
893 return; /* nothing to do */
894 try_alternative_plugins (neighbour);
895 min_latency = GNUNET_TIME_UNIT_FOREVER_REL;
897 mq = neighbour->messages;
898 now = GNUNET_TIME_absolute_get ();
899 pos = neighbour->plugins;
902 /* set plugins that are inactive for a long time back to disconnected */
903 if ((pos->timeout.value < now.value) && (pos->connected == GNUNET_YES))
906 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
907 "Marking long-time inactive connection to `%4s' as down.\n",
908 GNUNET_i2s (&neighbour->id));
910 pos->connected = GNUNET_NO;
912 if (((GNUNET_YES == pos->transmit_ready) ||
913 (mq->internal_msg)) &&
914 (pos->connect_attempts < MAX_CONNECT_RETRY) &&
915 ((rl == NULL) || (min_latency.value > pos->latency.value)))
918 min_latency = pos->latency;
925 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
926 "No plugin ready to transmit message\n");
928 return; /* nobody ready */
930 if (GNUNET_NO == rl->connected)
932 rl->connect_attempts++;
933 rl->connected = GNUNET_YES;
935 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
936 "Establishing fresh connection with `%4s' via plugin `%s'\n",
937 GNUNET_i2s (&neighbour->id), rl->plugin->short_name);
940 neighbour->messages = mq->next;
941 mq->plugin = rl->plugin;
942 if (!mq->internal_msg)
943 rl->transmit_ready = GNUNET_NO;
945 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
946 "Giving message of type `%u' for `%4s' to plugin `%s'\n",
947 ntohs (mq->message->type),
948 GNUNET_i2s (&neighbour->id), rl->plugin->short_name);
951 = rl->plugin->api->send (rl->plugin->api->cls,
957 GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
958 &transmit_send_continuation, mq);
963 * Send the specified message to the specified peer.
965 * @param client source of the transmission request (can be NULL)
966 * @param priority how important is the message
967 * @param msg message to send
968 * @param is_internal is this an internal message
969 * @param neighbour handle to the neighbour for transmission
972 transmit_to_peer (struct TransportClient *client,
973 unsigned int priority,
974 const struct GNUNET_MessageHeader *msg,
975 int is_internal, struct NeighbourList *neighbour)
977 struct MessageQueue *mq;
978 struct MessageQueue *mqe;
979 struct GNUNET_MessageHeader *m;
982 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
983 _("Sending message of type %u to peer `%4s'\n"),
984 ntohs (msg->type), GNUNET_i2s (&neighbour->id));
988 /* check for duplicate submission */
989 mq = neighbour->messages;
992 if (mq->client == client)
994 /* client transmitted to same peer twice
995 before getting SendOk! */
1002 mq = GNUNET_malloc (sizeof (struct MessageQueue));
1003 mq->client = client;
1004 m = GNUNET_malloc (ntohs (msg->size));
1005 memcpy (m, msg, ntohs (msg->size));
1007 mq->neighbour = neighbour;
1008 mq->internal_msg = is_internal;
1009 mq->priority = priority;
1012 mqe = neighbour->messages;
1014 while (mqe->next != NULL)
1019 neighbour->messages = mq;
1020 try_transmission_to_peer (neighbour);
1030 struct GeneratorContext
1032 struct TransportPlugin *plug_pos;
1033 struct AddressList *addr_pos;
1034 struct GNUNET_TIME_Absolute expiration;
1039 address_generator (void *cls, size_t max, void *buf)
1041 struct GeneratorContext *gc = cls;
1044 while ((gc->addr_pos == NULL) && (gc->plug_pos != NULL))
1046 gc->plug_pos = gc->plug_pos->next;
1047 gc->addr_pos = (gc->plug_pos != NULL) ? gc->plug_pos->addresses : NULL;
1049 if (NULL == gc->plug_pos)
1051 ret = GNUNET_HELLO_add_address (gc->plug_pos->short_name,
1054 gc->addr_pos->addrlen, buf, max);
1055 gc->addr_pos = gc->addr_pos->next;
1061 * Construct our HELLO message from all of the addresses of
1062 * all of the transports.
1067 struct GNUNET_HELLO_Message *hello;
1068 struct TransportClient *cpos;
1069 struct NeighbourList *npos;
1070 struct GeneratorContext gc;
1073 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1074 "Refreshing my `%s'\n",
1077 gc.plug_pos = plugins;
1078 gc.addr_pos = plugins != NULL ? plugins->addresses : NULL;
1079 gc.expiration = GNUNET_TIME_relative_to_absolute (HELLO_ADDRESS_EXPIRATION);
1080 hello = GNUNET_HELLO_create (&my_public_key, &address_generator, &gc);
1082 while (cpos != NULL)
1084 transmit_to_client (cpos,
1085 (const struct GNUNET_MessageHeader *) hello,
1090 GNUNET_free_non_null (our_hello);
1092 our_hello_version++;
1094 while (npos != NULL)
1097 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1098 "Transmitting updated `%s' to neighbour `%4s'\n",
1100 GNUNET_i2s(&npos->id));
1102 transmit_to_peer (NULL, 0,
1103 (const struct GNUNET_MessageHeader *) our_hello,
1111 * Task used to clean up expired addresses for a plugin.
1113 * @param cls closure
1117 expire_address_task (void *cls,
1118 const struct GNUNET_SCHEDULER_TaskContext *tc);
1122 * Update the list of addresses for this plugin,
1123 * expiring those that are past their expiration date.
1125 * @param plugin addresses of which plugin should be recomputed?
1126 * @param fresh set to GNUNET_YES if a new address was added
1127 * and we need to regenerate the HELLO even if nobody
1131 update_addresses (struct TransportPlugin *plugin, int fresh)
1133 struct GNUNET_TIME_Relative min_remaining;
1134 struct GNUNET_TIME_Relative remaining;
1135 struct GNUNET_TIME_Absolute now;
1136 struct AddressList *pos;
1137 struct AddressList *prev;
1138 struct AddressList *next;
1141 if (plugin->address_update_task != GNUNET_SCHEDULER_NO_PREREQUISITE_TASK)
1142 GNUNET_SCHEDULER_cancel (plugin->env.sched, plugin->address_update_task);
1143 plugin->address_update_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
1144 now = GNUNET_TIME_absolute_get ();
1145 min_remaining = GNUNET_TIME_UNIT_FOREVER_REL;
1146 expired = GNUNET_NO;
1148 pos = plugin->addresses;
1152 if (pos->expires.value < now.value)
1154 expired = GNUNET_YES;
1156 plugin->addresses = pos->next;
1158 prev->next = pos->next;
1163 remaining = GNUNET_TIME_absolute_get_remaining (pos->expires);
1164 if (remaining.value < min_remaining.value)
1165 min_remaining = remaining;
1171 if (expired || fresh)
1173 if (min_remaining.value < GNUNET_TIME_UNIT_FOREVER_REL.value)
1174 plugin->address_update_task
1175 = GNUNET_SCHEDULER_add_delayed (plugin->env.sched,
1177 GNUNET_SCHEDULER_PRIORITY_IDLE,
1178 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
1180 &expire_address_task, plugin);
1186 * Task used to clean up expired addresses for a plugin.
1188 * @param cls closure
1192 expire_address_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1194 struct TransportPlugin *plugin = cls;
1195 plugin->address_update_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
1196 update_addresses (plugin, GNUNET_NO);
1201 * Function that must be called by each plugin to notify the
1202 * transport service about the addresses under which the transport
1203 * provided by the plugin can be reached.
1205 * @param cls closure
1206 * @param name name of the transport that generated the address
1207 * @param addr one of the addresses of the host, NULL for the last address
1208 * the specific address format depends on the transport
1209 * @param addrlen length of the address
1210 * @param expires when should this address automatically expire?
1213 plugin_env_notify_address (void *cls,
1217 struct GNUNET_TIME_Relative expires)
1219 struct TransportPlugin *p = cls;
1220 struct AddressList *al;
1221 struct GNUNET_TIME_Absolute abex;
1223 abex = GNUNET_TIME_relative_to_absolute (expires);
1224 GNUNET_assert (p == find_transport (name));
1229 if ((addrlen == al->addrlen) && (0 == memcmp (addr, &al[1], addrlen)))
1231 if (al->expires.value < abex.value)
1238 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1239 "Plugin `%s' informs us about a new address `%s'\n", name,
1240 GNUNET_a2s(addr, addrlen));
1242 al = GNUNET_malloc (sizeof (struct AddressList) + addrlen);
1244 al->next = p->addresses;
1247 al->addrlen = addrlen;
1248 memcpy (&al[1], addr, addrlen);
1249 update_addresses (p, GNUNET_YES);
1253 struct LookupHelloContext
1255 GNUNET_TRANSPORT_AddressCallback iterator;
1262 lookup_address_callback (void *cls,
1264 struct GNUNET_TIME_Absolute expiration,
1265 const void *addr, size_t addrlen)
1267 struct LookupHelloContext *lhc = cls;
1268 lhc->iterator (lhc->iterator_cls, tname, addr, addrlen);
1274 lookup_hello_callback (void *cls,
1275 const struct GNUNET_PeerIdentity *peer,
1276 const struct GNUNET_HELLO_Message *h, uint32_t trust)
1278 struct LookupHelloContext *lhc = cls;
1282 lhc->iterator (lhc->iterator_cls, NULL, NULL, 0);
1288 GNUNET_HELLO_iterate_addresses (h,
1289 GNUNET_NO, &lookup_address_callback, lhc);
1294 * Function that allows a transport to query the known
1295 * network addresses for a given peer.
1297 * @param cls closure
1298 * @param timeout after how long should we time out?
1299 * @param target which peer are we looking for?
1300 * @param iter function to call for each known address
1301 * @param iter_cls closure for iter
1304 plugin_env_lookup_address (void *cls,
1305 struct GNUNET_TIME_Relative timeout,
1306 const struct GNUNET_PeerIdentity *target,
1307 GNUNET_TRANSPORT_AddressCallback iter,
1310 struct LookupHelloContext *lhc;
1312 lhc = GNUNET_malloc (sizeof (struct LookupHelloContext));
1313 lhc->iterator = iter;
1314 lhc->iterator_cls = iter_cls;
1315 GNUNET_PEERINFO_for_all (cfg,
1317 target, 0, timeout, &lookup_hello_callback, &lhc);
1322 * Notify all of our clients about a peer connecting.
1325 notify_clients_connect (const struct GNUNET_PeerIdentity *peer,
1326 struct GNUNET_TIME_Relative latency)
1328 struct ConnectInfoMessage cim;
1329 struct TransportClient *cpos;
1332 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1333 "Informing clients about peer `%4s' connecting to us\n",
1336 cim.header.size = htons (sizeof (struct ConnectInfoMessage));
1337 cim.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT);
1338 cim.quota_out = htonl (GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT / (60*1000));
1339 cim.latency = GNUNET_TIME_relative_hton (latency);
1340 memcpy (&cim.id, peer, sizeof (struct GNUNET_PeerIdentity));
1342 while (cpos != NULL)
1344 transmit_to_client (cpos, &cim.header, GNUNET_NO);
1351 * Notify all of our clients about a peer disconnecting.
1354 notify_clients_disconnect (const struct GNUNET_PeerIdentity *peer)
1356 struct DisconnectInfoMessage dim;
1357 struct TransportClient *cpos;
1360 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1361 "Informing clients about peer `%4s' disconnecting\n",
1364 dim.header.size = htons (sizeof (struct DisconnectInfoMessage));
1365 dim.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT);
1366 dim.reserved = htonl (0);
1367 memcpy (&dim.peer, peer, sizeof (struct GNUNET_PeerIdentity));
1369 while (cpos != NULL)
1371 transmit_to_client (cpos, &dim.header, GNUNET_NO);
1378 * Copy any validated addresses to buf.
1380 * @return 0 once all addresses have been
1384 list_validated_addresses (void *cls, size_t max, void *buf)
1386 struct ValidationAddress **va = cls;
1389 while ((NULL != *va) && ((*va)->ok != GNUNET_YES))
1393 ret = GNUNET_HELLO_add_address ((*va)->transport_name,
1395 &(*va)[1], (*va)->addr_len, buf, max);
1402 * HELLO validation cleanup task.
1405 cleanup_validation (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1407 struct ValidationAddress *va;
1408 struct ValidationList *pos;
1409 struct ValidationList *prev;
1410 struct GNUNET_TIME_Absolute now;
1411 struct GNUNET_HELLO_Message *hello;
1412 struct GNUNET_PeerIdentity pid;
1413 struct NeighbourList *n;
1416 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1417 "HELLO validation cleanup background task running...\n");
1419 now = GNUNET_TIME_absolute_get ();
1421 pos = pending_validations;
1424 if (pos->timeout.value < now.value)
1427 pending_validations = pos->next;
1429 prev->next = pos->next;
1430 va = pos->addresses;
1431 hello = GNUNET_HELLO_create (&pos->publicKey,
1432 &list_validated_addresses, &va);
1433 GNUNET_CRYPTO_hash (&pos->publicKey,
1435 GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
1438 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1439 "Creating persistent `%s' message for peer `%4s' based on confirmed addresses.\n",
1440 "HELLO", GNUNET_i2s (&pid));
1442 GNUNET_PEERINFO_add_peer (cfg, sched, &pid, hello);
1443 n = find_neighbour (&pid);
1445 try_transmission_to_peer (n);
1446 GNUNET_free (hello);
1447 while (NULL != (va = pos->addresses))
1449 pos->addresses = va->next;
1450 GNUNET_free (va->transport_name);
1455 pos = pending_validations;
1464 /* finally, reschedule cleanup if needed; list is
1465 ordered by timeout, so we need the last element... */
1466 pos = pending_validations;
1467 while ((pos != NULL) && (pos->next != NULL))
1470 GNUNET_SCHEDULER_add_delayed (sched,
1472 GNUNET_SCHEDULER_PRIORITY_IDLE,
1473 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
1474 GNUNET_TIME_absolute_get_remaining
1475 (pos->timeout), &cleanup_validation, NULL);
1482 * Function that will be called if we receive a validation
1483 * of an address challenge that we transmitted to another
1484 * peer. Note that the validation should only be considered
1485 * acceptable if the challenge matches AND if the sender
1486 * address is at least a plausible address for this peer
1487 * (otherwise we may be seeing a MiM attack).
1489 * @param cls closure
1490 * @param name name of the transport that generated the address
1491 * @param peer who responded to our challenge
1492 * @param challenge the challenge number we presumably used
1493 * @param sender_addr string describing our sender address (as observed
1494 * by the other peer in human-readable format)
1497 plugin_env_notify_validation (void *cls,
1499 const struct GNUNET_PeerIdentity *peer,
1501 const char *sender_addr)
1505 struct ValidationList *pos;
1506 struct ValidationAddress *va;
1507 struct GNUNET_PeerIdentity id;
1509 pos = pending_validations;
1512 GNUNET_CRYPTO_hash (&pos->publicKey,
1514 GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
1517 memcmp (peer, &id, sizeof (struct GNUNET_PeerIdentity)))
1523 /* TODO: call statistics (unmatched PONG) */
1524 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1526 ("Received validation response but have no record of any validation request for `%4s'. Ignoring.\n"),
1530 all_done = GNUNET_YES;
1531 matched = GNUNET_NO;
1532 va = pos->addresses;
1535 if (va->challenge == challenge)
1538 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1539 "Confirmed validity of peer address.\n");
1541 GNUNET_log (GNUNET_ERROR_TYPE_INFO | GNUNET_ERROR_TYPE_BULK,
1542 _("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"),
1545 va->ok = GNUNET_YES;
1547 GNUNET_TIME_relative_to_absolute (HELLO_ADDRESS_EXPIRATION);
1548 matched = GNUNET_YES;
1550 if (va->ok != GNUNET_YES)
1551 all_done = GNUNET_NO;
1554 if (GNUNET_NO == matched)
1556 /* TODO: call statistics (unmatched PONG) */
1557 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1559 ("Received `%s' message but have no record of a matching `%s' message. Ignoring.\n"),
1562 if (GNUNET_YES == all_done)
1564 pos->timeout.value = 0;
1565 GNUNET_SCHEDULER_add_delayed (sched,
1567 GNUNET_SCHEDULER_PRIORITY_IDLE,
1568 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
1569 GNUNET_TIME_UNIT_ZERO,
1570 &cleanup_validation, NULL);
1575 struct CheckHelloValidatedContext
1578 * Plugin for which we are validating.
1580 struct TransportPlugin *plugin;
1583 * Hello that we are validating.
1585 struct GNUNET_HELLO_Message *hello;
1588 * Validation list being build.
1590 struct ValidationList *e;
1596 * Append the given address to the list of entries
1597 * that need to be validated.
1600 run_validation (void *cls,
1602 struct GNUNET_TIME_Absolute expiration,
1603 const void *addr, size_t addrlen)
1605 struct ValidationList *e = cls;
1606 struct TransportPlugin *tp;
1607 struct ValidationAddress *va;
1608 struct GNUNET_PeerIdentity id;
1610 tp = find_transport (tname);
1613 GNUNET_log (GNUNET_ERROR_TYPE_INFO |
1614 GNUNET_ERROR_TYPE_BULK,
1616 ("Transport `%s' not loaded, will not try to validate peer address using this transport.\n"),
1620 GNUNET_CRYPTO_hash (&e->publicKey,
1622 GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
1624 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1625 "Scheduling validation of address `%s' via `%s' for `%4s'\n",
1626 GNUNET_a2s(addr, addrlen),
1630 va = GNUNET_malloc (sizeof (struct ValidationAddress) + addrlen);
1631 va->next = e->addresses;
1633 va->transport_name = GNUNET_strdup (tname);
1634 va->addr_len = addrlen;
1635 va->challenge = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1637 memcpy (&va[1], addr, addrlen);
1643 * Check if addresses in validated hello "h" overlap with
1644 * those in "chvc->hello" and update "chvc->hello" accordingly,
1645 * removing those addresses that have already been validated.
1648 check_hello_validated (void *cls,
1649 const struct GNUNET_PeerIdentity *peer,
1650 const struct GNUNET_HELLO_Message *h,
1653 struct CheckHelloValidatedContext *chvc = cls;
1654 struct ValidationAddress *va;
1655 struct TransportPlugin *tp;
1657 struct GNUNET_PeerIdentity apeer;
1659 first_call = GNUNET_NO;
1660 if (chvc->e == NULL)
1662 first_call = GNUNET_YES;
1663 chvc->e = GNUNET_malloc (sizeof (struct ValidationList));
1664 GNUNET_assert (GNUNET_OK ==
1665 GNUNET_HELLO_get_key (h != NULL ? h : chvc->hello,
1666 &chvc->e->publicKey));
1668 GNUNET_TIME_relative_to_absolute (HELLO_VERIFICATION_TIMEOUT);
1669 chvc->e->next = pending_validations;
1670 pending_validations = chvc->e;
1674 GNUNET_HELLO_iterate_new_addresses (chvc->hello,
1676 GNUNET_TIME_absolute_get (),
1677 &run_validation, chvc->e);
1679 else if (GNUNET_YES == first_call)
1681 /* no existing HELLO, all addresses are new */
1682 GNUNET_HELLO_iterate_addresses (chvc->hello,
1683 GNUNET_NO, &run_validation, chvc->e);
1686 return; /* wait for next call */
1687 /* finally, transmit validation attempts */
1688 GNUNET_assert (GNUNET_OK ==
1689 GNUNET_HELLO_get_id (chvc->hello,
1691 va = chvc->e->addresses;
1695 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1696 "Establishing `%s' connection to validate `%s' of `%4s'\n",
1699 GNUNET_i2s (&apeer));
1701 tp = find_transport (va->transport_name);
1702 GNUNET_assert (tp != NULL);
1704 tp->api->validate (tp->api->cls,
1707 HELLO_VERIFICATION_TIMEOUT,
1710 va->ok = GNUNET_SYSERR;
1713 if (chvc->e->next == NULL)
1714 GNUNET_SCHEDULER_add_delayed (sched,
1716 GNUNET_SCHEDULER_PRIORITY_IDLE,
1717 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
1718 GNUNET_TIME_absolute_get_remaining
1719 (chvc->e->timeout), &cleanup_validation,
1726 * Process HELLO-message.
1728 * @param plugin transport involved, may be NULL
1729 * @param message the actual message
1730 * @return GNUNET_OK if the HELLO was well-formed, GNUNET_SYSERR otherwise
1733 process_hello (struct TransportPlugin *plugin,
1734 const struct GNUNET_MessageHeader *message)
1736 struct ValidationList *e;
1738 struct GNUNET_PeerIdentity target;
1739 const struct GNUNET_HELLO_Message *hello;
1740 struct CheckHelloValidatedContext *chvc;
1741 struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded publicKey;
1743 hsize = ntohs (message->size);
1744 if ((ntohs (message->type) != GNUNET_MESSAGE_TYPE_HELLO) ||
1745 (hsize < sizeof (struct GNUNET_MessageHeader)))
1748 return GNUNET_SYSERR;
1750 /* first, check if load is too high */
1751 if (GNUNET_OS_load_cpu_get (cfg) > 100)
1753 /* TODO: call to stats? */
1756 hello = (const struct GNUNET_HELLO_Message *) message;
1757 if (GNUNET_OK != GNUNET_HELLO_get_key (hello, &publicKey))
1759 GNUNET_break_op (0);
1760 return GNUNET_SYSERR;
1762 GNUNET_CRYPTO_hash (&publicKey,
1763 sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
1764 &target.hashPubKey);
1766 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1767 "Processing `%s' message for `%4s'\n",
1768 "HELLO", GNUNET_i2s (&target));
1770 /* check if a HELLO for this peer is already on the validation list */
1771 e = pending_validations;
1774 if (0 == memcmp (&e->publicKey,
1777 GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded)))
1779 /* TODO: call to stats? */
1781 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1782 "`%s' message for peer `%4s' is already pending; ignoring new message\n",
1783 "HELLO", GNUNET_i2s (&target));
1789 chvc = GNUNET_malloc (sizeof (struct CheckHelloValidatedContext) + hsize);
1790 chvc->plugin = plugin;
1791 chvc->hello = (struct GNUNET_HELLO_Message *) &chvc[1];
1792 memcpy (chvc->hello, hello, hsize);
1793 /* finally, check if HELLO was previously validated
1794 (continuation will then schedule actual validation) */
1795 GNUNET_PEERINFO_for_all (cfg,
1799 HELLO_VERIFICATION_TIMEOUT,
1800 &check_hello_validated, chvc);
1807 * The peer specified by the given neighbour has timed-out. Update
1808 * our state and do the necessary notifications. Also notifies
1809 * our clients that the neighbour is now officially gone.
1811 * @param n the neighbour list entry for the peer
1814 disconnect_neighbour (struct NeighbourList *n)
1816 struct ReadyList *rpos;
1817 struct NeighbourList *npos;
1818 struct NeighbourList *nprev;
1819 struct MessageQueue *mq;
1822 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1823 "Disconnecting from neighbour\n");
1825 /* remove n from neighbours list */
1828 while ((npos != NULL) && (npos != n))
1833 GNUNET_assert (npos != NULL);
1835 neighbours = n->next;
1837 nprev->next = n->next;
1839 /* notify all clients about disconnect */
1840 notify_clients_disconnect (&n->id);
1842 /* clean up all plugins, cancel connections & pending transmissions */
1843 while (NULL != (rpos = n->plugins))
1845 n->plugins = rpos->next;
1846 GNUNET_assert (rpos->neighbour == n);
1847 rpos->plugin->api->cancel (rpos->plugin->api->cls,
1848 rpos->plugin_handle, rpos, &n->id);
1852 /* free all messages on the queue */
1853 while (NULL != (mq = n->messages))
1855 n->messages = mq->next;
1856 GNUNET_assert (mq->neighbour == n);
1860 /* finally, free n itself */
1866 * Add an entry for each of our transport plugins
1867 * (that are able to send) to the list of plugins
1868 * for this neighbour.
1870 * @param neighbour to initialize
1873 add_plugins (struct NeighbourList *neighbour)
1875 struct TransportPlugin *tp;
1876 struct ReadyList *rl;
1878 neighbour->retry_plugins_time
1879 = GNUNET_TIME_relative_to_absolute (PLUGIN_RETRY_FREQUENCY);
1883 if (tp->api->send != NULL)
1885 rl = GNUNET_malloc (sizeof (struct ReadyList));
1886 rl->next = neighbour->plugins;
1887 neighbour->plugins = rl;
1889 rl->neighbour = neighbour;
1890 rl->transmit_ready = GNUNET_YES;
1898 neighbour_timeout_task (void *cls,
1899 const struct GNUNET_SCHEDULER_TaskContext *tc)
1901 struct NeighbourList *n = cls;
1904 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1905 "Neighbour has timed out!\n");
1907 n->timeout_task = GNUNET_SCHEDULER_NO_PREREQUISITE_TASK;
1908 disconnect_neighbour (n);
1914 * Create a fresh entry in our neighbour list for the given peer.
1915 * Will try to transmit our current HELLO to the new neighbour. Also
1916 * notifies our clients about the new "connection".
1918 * @param peer the peer for which we create the entry
1919 * @return the new neighbour list entry
1921 static struct NeighbourList *
1922 setup_new_neighbour (const struct GNUNET_PeerIdentity *peer)
1924 struct NeighbourList *n;
1927 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
1928 "Setting up new neighbour `%4s', sending our HELLO to introduce ourselves\n",
1931 GNUNET_assert (our_hello != NULL);
1932 n = GNUNET_malloc (sizeof (struct NeighbourList));
1933 n->next = neighbours;
1936 n->last_quota_update = GNUNET_TIME_absolute_get ();
1938 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT);
1939 n->quota_in = (GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT + 59999) / (60 * 1000);
1941 n->timeout_task = GNUNET_SCHEDULER_add_delayed (sched,
1943 GNUNET_SCHEDULER_PRIORITY_IDLE,
1944 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
1945 GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
1946 &neighbour_timeout_task, n);
1947 transmit_to_peer (NULL, 0,
1948 (const struct GNUNET_MessageHeader *) our_hello,
1950 notify_clients_connect (peer, GNUNET_TIME_UNIT_FOREVER_REL);
1956 * Function called by the plugin for each received message.
1957 * Update data volumes, possibly notify plugins about
1958 * reducing the rate at which they read from the socket
1959 * and generally forward to our receive callback.
1961 * @param plugin_context value to pass to this plugin
1962 * to respond to the given peer (use is optional,
1963 * but may speed up processing)
1964 * @param service_context value passed to the transport-service
1965 * to identify the neighbour; will be NULL on the first
1966 * call for a given peer
1967 * @param latency estimated latency for communicating with the
1969 * @param peer (claimed) identity of the other peer
1970 * @param message the message, NULL if peer was disconnected
1971 * @return the new service_context that the plugin should use
1972 * for future receive calls for messages from this
1975 static struct ReadyList *
1976 plugin_env_receive (void *cls,
1977 void *plugin_context,
1978 struct ReadyList *service_context,
1979 struct GNUNET_TIME_Relative latency,
1980 const struct GNUNET_PeerIdentity *peer,
1981 const struct GNUNET_MessageHeader *message)
1983 const struct GNUNET_MessageHeader ack = {
1984 htons (sizeof (struct GNUNET_MessageHeader)),
1985 htons (GNUNET_MESSAGE_TYPE_TRANSPORT_ACK)
1987 struct TransportPlugin *plugin = cls;
1988 struct TransportClient *cpos;
1989 struct InboundMessage *im;
1991 struct NeighbourList *n;
1993 if (service_context != NULL)
1995 n = service_context->neighbour;
1996 GNUNET_assert (n != NULL);
2000 n = find_neighbour (peer);
2003 if (message == NULL)
2004 return NULL; /* disconnect of peer already marked down */
2005 n = setup_new_neighbour (peer);
2007 service_context = n->plugins;
2008 while ((service_context != NULL) && (plugin != service_context->plugin))
2009 service_context = service_context->next;
2010 GNUNET_assert ((plugin->api->send == NULL) ||
2011 (service_context != NULL));
2013 if (message == NULL)
2015 if ((service_context != NULL) &&
2016 (service_context->plugin_handle == plugin_context))
2018 service_context->connected = GNUNET_NO;
2019 service_context->plugin_handle = NULL;
2021 /* TODO: call stats */
2025 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
2026 "Processing message of type `%u' received by plugin...\n",
2027 ntohs (message->type));
2029 if (service_context != NULL)
2031 if (service_context->connected == GNUNET_NO)
2033 service_context->connected = GNUNET_YES;
2034 service_context->transmit_ready = GNUNET_YES;
2035 service_context->connect_attempts++;
2037 service_context->timeout
2038 = GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT);
2039 service_context->plugin_handle = plugin_context;
2040 service_context->latency = latency;
2042 /* update traffic received amount ... */
2043 msize = ntohs (message->size);
2044 n->last_received += msize;
2045 GNUNET_SCHEDULER_cancel (sched, n->timeout_task);
2047 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT);
2049 GNUNET_SCHEDULER_add_delayed (sched, GNUNET_NO,
2050 GNUNET_SCHEDULER_PRIORITY_IDLE,
2051 GNUNET_SCHEDULER_NO_PREREQUISITE_TASK,
2052 GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
2053 &neighbour_timeout_task, n);
2055 if (n->quota_violation_count > QUOTA_VIOLATION_DROP_THRESHOLD)
2057 /* dropping message due to frequent inbound volume violations! */
2058 GNUNET_log (GNUNET_ERROR_TYPE_WARNING |
2059 GNUNET_ERROR_TYPE_BULK,
2061 ("Dropping incoming message due to repeated bandwidth quota violations.\n"));
2062 /* TODO: call stats */
2063 GNUNET_assert (NULL != service_context->neighbour);
2064 return service_context;
2066 switch (ntohs (message->type))
2068 case GNUNET_MESSAGE_TYPE_HELLO:
2070 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2071 "Receiving `%s' message from `%4s'.\n", "HELLO",
2074 process_hello (plugin, message);
2076 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2077 "Sending `%s' message to connecting peer `%4s'.\n", "ACK",
2080 transmit_to_peer (NULL, 0, &ack, GNUNET_YES, n);
2082 case GNUNET_MESSAGE_TYPE_TRANSPORT_ACK:
2083 n->saw_ack = GNUNET_YES;
2084 /* intentional fall-through! */
2087 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2088 "Received message of type %u from `%4s', sending to all clients.\n",
2089 ntohs (message->type),
2092 /* transmit message to all clients */
2093 im = GNUNET_malloc (sizeof (struct InboundMessage) + msize);
2094 im->header.size = htons (sizeof (struct InboundMessage) + msize);
2095 im->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_RECV);
2096 im->latency = GNUNET_TIME_relative_hton (latency);
2098 memcpy (&im[1], message, msize);
2101 while (cpos != NULL)
2103 transmit_to_client (cpos, &im->header, GNUNET_YES);
2108 GNUNET_assert (NULL != service_context->neighbour);
2109 return service_context;
2114 * Handle START-message. This is the first message sent to us
2115 * by any client which causes us to add it to our list.
2117 * @param cls closure (always NULL)
2118 * @param client identification of the client
2119 * @param message the actual message
2122 handle_start (void *cls,
2123 struct GNUNET_SERVER_Client *client,
2124 const struct GNUNET_MessageHeader *message)
2126 struct TransportClient *c;
2127 struct ConnectInfoMessage cim;
2128 struct NeighbourList *n;
2129 struct InboundMessage *im;
2130 struct GNUNET_MessageHeader *ack;
2133 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2134 "Received `%s' request from client\n", "START");
2139 if (c->client == client)
2141 /* client already on our list! */
2143 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
2148 c = GNUNET_malloc (sizeof (struct TransportClient));
2152 if (our_hello != NULL)
2155 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2156 "Sending our own HELLO to new client\n");
2158 transmit_to_client (c,
2159 (const struct GNUNET_MessageHeader *) our_hello,
2161 /* tell new client about all existing connections */
2162 cim.header.size = htons (sizeof (struct ConnectInfoMessage));
2163 cim.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT);
2164 cim.quota_out = htonl (GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT / (60 * 1000));
2165 cim.latency = GNUNET_TIME_relative_hton (GNUNET_TIME_UNIT_ZERO); /* FIXME? */
2166 im = GNUNET_malloc (sizeof (struct InboundMessage) +
2167 sizeof (struct GNUNET_MessageHeader));
2168 im->header.size = htons (sizeof (struct InboundMessage) +
2169 sizeof (struct GNUNET_MessageHeader));
2170 im->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_RECV);
2171 im->latency = GNUNET_TIME_relative_hton (GNUNET_TIME_UNIT_ZERO); /* FIXME? */
2172 ack = (struct GNUNET_MessageHeader *) &im[1];
2173 ack->size = htons (sizeof (struct GNUNET_MessageHeader));
2174 ack->type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_ACK);
2175 for (n = neighbours; n != NULL; n = n->next)
2178 transmit_to_client (c, &cim.header, GNUNET_NO);
2182 transmit_to_client (c, &im->header, GNUNET_NO);
2187 GNUNET_SERVER_receive_done (client, GNUNET_OK);
2192 * Handle HELLO-message.
2194 * @param cls closure (always NULL)
2195 * @param client identification of the client
2196 * @param message the actual message
2199 handle_hello (void *cls,
2200 struct GNUNET_SERVER_Client *client,
2201 const struct GNUNET_MessageHeader *message)
2206 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2207 "Received `%s' request from client\n", "HELLO");
2209 ret = process_hello (NULL, message);
2210 GNUNET_SERVER_receive_done (client, ret);
2215 * Handle SEND-message.
2217 * @param cls closure (always NULL)
2218 * @param client identification of the client
2219 * @param message the actual message
2222 handle_send (void *cls,
2223 struct GNUNET_SERVER_Client *client,
2224 const struct GNUNET_MessageHeader *message)
2226 struct TransportClient *tc;
2227 struct NeighbourList *n;
2228 const struct OutboundMessage *obm;
2229 const struct GNUNET_MessageHeader *obmm;
2233 size = ntohs (message->size);
2235 sizeof (struct OutboundMessage) + sizeof (struct GNUNET_MessageHeader))
2238 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
2241 obm = (const struct OutboundMessage *) message;
2243 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2244 "Received `%s' request from client with target `%4s'\n",
2245 "SEND", GNUNET_i2s (&obm->peer));
2247 obmm = (const struct GNUNET_MessageHeader *) &obm[1];
2248 msize = ntohs (obmm->size);
2249 if (size != msize + sizeof (struct OutboundMessage))
2252 GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
2255 n = find_neighbour (&obm->peer);
2257 n = setup_new_neighbour (&obm->peer);
2259 while ((tc != NULL) && (tc->client != client))
2263 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2264 "Client asked to transmit %u-byte message of type %u to `%4s'\n",
2266 ntohs (obmm->type), GNUNET_i2s (&obm->peer));
2268 transmit_to_peer (tc, ntohl(obm->priority), obmm, GNUNET_NO, n);
2269 GNUNET_SERVER_receive_done (client, GNUNET_OK);
2274 * Handle SET_QUOTA-message.
2276 * @param cls closure (always NULL)
2277 * @param client identification of the client
2278 * @param message the actual message
2281 handle_set_quota (void *cls,
2282 struct GNUNET_SERVER_Client *client,
2283 const struct GNUNET_MessageHeader *message)
2285 const struct QuotaSetMessage *qsm =
2286 (const struct QuotaSetMessage *) message;
2287 struct NeighbourList *n;
2288 struct TransportPlugin *p;
2289 struct ReadyList *rl;
2292 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2293 "Received `%s' request from client for peer `%4s'\n",
2294 "SET_QUOTA", GNUNET_i2s (&qsm->peer));
2296 n = find_neighbour (&qsm->peer);
2299 GNUNET_SERVER_receive_done (client, GNUNET_OK);
2303 if (n->quota_in < ntohl (qsm->quota_in))
2304 n->last_quota_update = GNUNET_TIME_absolute_get ();
2305 n->quota_in = ntohl (qsm->quota_in);
2310 p->api->set_receive_quota (p->api->cls,
2311 &qsm->peer, ntohl (qsm->quota_in));
2314 GNUNET_SERVER_receive_done (client, GNUNET_OK);
2319 * Handle TRY_CONNECT-message.
2321 * @param cls closure (always NULL)
2322 * @param client identification of the client
2323 * @param message the actual message
2326 handle_try_connect (void *cls,
2327 struct GNUNET_SERVER_Client *client,
2328 const struct GNUNET_MessageHeader *message)
2330 const struct TryConnectMessage *tcm;
2332 tcm = (const struct TryConnectMessage *) message;
2334 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2335 "Received `%s' request from client asking to connect to `%4s'\n",
2336 "TRY_CONNECT", GNUNET_i2s (&tcm->peer));
2338 if (NULL == find_neighbour (&tcm->peer))
2339 setup_new_neighbour (&tcm->peer);
2340 GNUNET_SERVER_receive_done (client, GNUNET_OK);
2345 * List of handlers for the messages understood by this
2348 static struct GNUNET_SERVER_MessageHandler handlers[] = {
2349 {&handle_start, NULL,
2350 GNUNET_MESSAGE_TYPE_TRANSPORT_START, 0},
2351 {&handle_hello, NULL,
2352 GNUNET_MESSAGE_TYPE_HELLO, 0},
2353 {&handle_send, NULL,
2354 GNUNET_MESSAGE_TYPE_TRANSPORT_SEND, 0},
2355 {&handle_set_quota, NULL,
2356 GNUNET_MESSAGE_TYPE_TRANSPORT_SET_QUOTA, sizeof (struct QuotaSetMessage)},
2357 {&handle_try_connect, NULL,
2358 GNUNET_MESSAGE_TYPE_TRANSPORT_TRY_CONNECT,
2359 sizeof (struct TryConnectMessage)},
2365 * Setup the environment for this plugin.
2368 create_environment (struct TransportPlugin *plug)
2370 plug->env.cfg = cfg;
2371 plug->env.sched = sched;
2372 plug->env.my_public_key = &my_public_key;
2373 plug->env.my_private_key = my_private_key;
2374 plug->env.my_identity = &my_identity;
2375 plug->env.cls = plug;
2376 plug->env.receive = &plugin_env_receive;
2377 plug->env.lookup = &plugin_env_lookup_address;
2378 plug->env.notify_address = &plugin_env_notify_address;
2379 plug->env.notify_validation = &plugin_env_notify_validation;
2380 plug->env.default_quota_in = (GNUNET_CONSTANTS_DEFAULT_BPM_IN_OUT + 59999) / (60 * 1000);
2381 plug->env.max_connections = max_connect_per_transport;
2386 * Start the specified transport (load the plugin).
2389 start_transport (struct GNUNET_SERVER_Handle *server, const char *name)
2391 struct TransportPlugin *plug;
2394 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2395 _("Loading `%s' transport plugin\n"), name);
2396 GNUNET_asprintf (&libname, "libgnunet_plugin_transport_%s", name);
2397 plug = GNUNET_malloc (sizeof (struct TransportPlugin));
2398 create_environment (plug);
2399 plug->short_name = GNUNET_strdup (name);
2400 plug->lib_name = libname;
2401 plug->next = plugins;
2403 plug->api = GNUNET_PLUGIN_load (libname, &plug->env);
2404 if (plug->api == NULL)
2406 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2407 _("Failed to load transport plugin for `%s'\n"), name);
2408 GNUNET_free (plug->short_name);
2409 plugins = plug->next;
2410 GNUNET_free (libname);
2417 * Called whenever a client is disconnected. Frees our
2418 * resources associated with that client.
2420 * @param cls closure
2421 * @param client identification of the client
2424 client_disconnect_notification (void *cls,
2425 struct GNUNET_SERVER_Client *client)
2427 struct TransportClient *pos;
2428 struct TransportClient *prev;
2429 struct ClientMessageQueueEntry *mqe;
2432 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
2433 "Client disconnected, cleaning up.\n");
2437 while ((pos != NULL) && (pos->client != client))
2444 while (NULL != (mqe = pos->message_queue_head))
2446 pos->message_queue_head = mqe->next;
2449 pos->message_queue_head = NULL;
2451 clients = pos->next;
2453 prev->next = pos->next;
2454 if (GNUNET_YES == pos->tcs_pending)
2464 * Initiate transport service.
2466 * @param cls closure
2467 * @param s scheduler to use
2468 * @param serv the initialized server
2469 * @param c configuration to use
2473 struct GNUNET_SCHEDULER_Handle *s,
2474 struct GNUNET_SERVER_Handle *serv, struct GNUNET_CONFIGURATION_Handle *c)
2479 unsigned long long tneigh;
2484 /* parse configuration */
2486 GNUNET_CONFIGURATION_get_value_number (c,
2491 GNUNET_CONFIGURATION_get_value_filename (c,
2493 "HOSTKEY", &keyfile)))
2495 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2497 ("Transport service is lacking key configuration settings. Exiting.\n"));
2498 GNUNET_SCHEDULER_shutdown (s);
2501 max_connect_per_transport = (uint32_t) tneigh;
2502 my_private_key = GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
2503 GNUNET_free (keyfile);
2504 if (my_private_key == NULL)
2506 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
2508 ("Transport service could not access hostkey. Exiting.\n"));
2509 GNUNET_SCHEDULER_shutdown (s);
2512 GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &my_public_key);
2513 GNUNET_CRYPTO_hash (&my_public_key,
2514 sizeof (my_public_key), &my_identity.hashPubKey);
2515 /* setup notification */
2517 GNUNET_SERVER_disconnect_notify (server,
2518 &client_disconnect_notification, NULL);
2519 /* load plugins... */
2522 GNUNET_CONFIGURATION_get_value_string (c,
2523 "TRANSPORT", "PLUGINS", &plugs))
2525 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2526 _("Starting transport plugins `%s'\n"), plugs);
2527 pos = strtok (plugs, " ");
2530 start_transport (server, pos);
2532 pos = strtok (NULL, " ");
2534 GNUNET_free (plugs);
2539 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
2540 _("Transport service ready.\n"));
2542 /* process client requests */
2543 GNUNET_SERVER_add_handlers (server, handlers);
2548 * Function called when the service shuts
2549 * down. Unloads our plugins.
2551 * @param cls closure
2552 * @param cfg configuration to use
2555 unload_plugins (void *cls, struct GNUNET_CONFIGURATION_Handle *cfg)
2557 struct TransportPlugin *plug;
2558 struct AddressList *al;
2561 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2562 "Transport service is unloading plugins...\n");
2564 while (NULL != (plug = plugins))
2566 plugins = plug->next;
2567 GNUNET_break (NULL == GNUNET_PLUGIN_unload (plug->lib_name, plug->api));
2568 GNUNET_free (plug->lib_name);
2569 GNUNET_free (plug->short_name);
2570 while (NULL != (al = plug->addresses))
2572 plug->addresses = al->next;
2577 if (my_private_key != NULL)
2578 GNUNET_CRYPTO_rsa_key_free (my_private_key);
2583 * The main function for the transport service.
2585 * @param argc number of arguments from the command line
2586 * @param argv command line arguments
2587 * @return 0 ok, 1 on error
2590 main (int argc, char *const *argv)
2592 return (GNUNET_OK ==
2593 GNUNET_SERVICE_run (argc,
2596 &run, NULL, &unload_plugins, NULL)) ? 0 : 1;
2599 /* end of gnunet-service-transport.c */