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3 (C) 2010,2011 Christian Grothoff (and other contributing authors)
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22 * @file transport/gnunet-service-transport_neighbours.c
23 * @brief neighbour management
24 * @author Christian Grothoff
27 #include "gnunet_ats_service.h"
28 #include "gnunet-service-transport_neighbours.h"
29 #include "gnunet-service-transport_validation.h"
30 #include "gnunet-service-transport.h"
31 #include "gnunet_peerinfo_service.h"
32 #include "gnunet_constants.h"
33 #include "transport.h"
37 * Size of the neighbour hash map.
39 #define NEIGHBOUR_TABLE_SIZE 256
44 // - have a way to access the currently 'connected' session
45 // (for sending and to notice disconnect of it!)
46 // - have a way to access/update bandwidth/quota information per peer
47 // (for CostReport/TrafficReport callbacks)
50 struct NeighbourMapEntry;
53 * For each neighbour we keep a list of messages
54 * that we still want to transmit to the neighbour.
60 * This is a doubly linked list.
62 struct MessageQueue *next;
65 * This is a doubly linked list.
67 struct MessageQueue *prev;
70 * The message(s) we want to transmit, GNUNET_MessageHeader(s)
71 * stuck together in memory. Allocated at the end of this struct.
73 const char *message_buf;
76 * Size of the message buf
78 size_t message_buf_size;
81 * Client responsible for queueing the message; used to check that a
82 * client has no two messages pending for the same target and to
83 * notify the client of a successful transmission; NULL if this is
84 * an internal message.
86 struct TransportClient *client;
89 * At what time should we fail?
91 struct GNUNET_TIME_Absolute timeout;
94 * Internal message of the transport system that should not be
95 * included in the usual SEND-SEND_OK transmission confirmation
96 * traffic management scheme. Typically, "internal_msg" will
97 * be set whenever "client" is NULL (but it is not strictly
103 * How important is the message?
105 unsigned int priority;
111 * Entry in neighbours.
113 struct NeighbourMapEntry
117 * Head of list of messages we would like to send to this peer;
118 * must contain at most one message per client.
120 struct MessageQueue *messages_head;
123 * Tail of list of messages we would like to send to this peer; must
124 * contain at most one message per client.
126 struct MessageQueue *messages_tail;
129 * Context for address suggestion.
130 * NULL after we are connected.
132 struct GNUNET_ATS_SuggestionContext *asc;
135 * Performance data for the peer.
137 struct GNUNET_TRANSPORT_ATS_Information *ats;
140 * Active session for communicating with the peer.
142 struct Session *session;
145 * Name of the plugin we currently use.
150 * Address used for communicating with the peer, NULL for inbound connections.
155 * Number of bytes in 'addr'.
160 * Public key for this peer. Valid only if the respective flag is set below.
162 struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded public_key;
165 * Identity of this neighbour.
167 struct GNUNET_PeerIdentity id;
170 * ID of task scheduled to run when this peer is about to
171 * time out (will free resources associated with the peer).
173 GNUNET_SCHEDULER_TaskIdentifier timeout_task;
176 * ID of task scheduled to run when we should retry transmitting
177 * the head of the message queue. Actually triggered when the
178 * transmission is timing out (we trigger instantly when we have
179 * a chance of success).
181 GNUNET_SCHEDULER_TaskIdentifier retry_task;
184 * How long until we should consider this peer dead (if we don't
185 * receive another message in the meantime)?
187 struct GNUNET_TIME_Absolute peer_timeout;
190 * Tracker for inbound bandwidth.
192 struct GNUNET_BANDWIDTH_Tracker in_tracker;
195 * How often has the other peer (recently) violated the inbound
196 * traffic limit? Incremented by 10 per violation, decremented by 1
197 * per non-violation (for each time interval).
199 unsigned int quota_violation_count;
202 * Number of values in 'ats' array.
204 unsigned int ats_count;
207 * Have we seen an PONG from this neighbour in the past (and
208 * not had a disconnect since)?
213 * Do we have a valid public key for this neighbour?
215 int public_key_valid;
218 * Are we already in the process of disconnecting this neighbour?
223 * Do we currently consider this neighbour connected? (as far as
224 * the connect/disconnect callbacks are concerned)?
232 * All known neighbours and their HELLOs.
234 static struct GNUNET_CONTAINER_MultiHashMap *neighbours;
237 * Closure for connect_notify_cb and disconnect_notify_cb
239 static void *callback_cls;
242 * Function to call when we connected to a neighbour.
244 static GNUNET_TRANSPORT_NotifyConnect connect_notify_cb;
247 * Function to call when we disconnected from a neighbour.
249 static GNUNET_TRANSPORT_NotifyDisconnect disconnect_notify_cb;
253 * Lookup a neighbour entry in the neighbours hash map.
255 * @param pid identity of the peer to look up
256 * @return the entry, NULL if there is no existing record
258 static struct NeighbourMapEntry *
259 lookup_neighbour (const struct GNUNET_PeerIdentity *pid)
261 return GNUNET_CONTAINER_multihashmap_get (neighbours,
268 * Check the ready list for the given neighbour and if a plugin is
269 * ready for transmission (and if we have a message), do so!
271 * @param neighbour target peer for which to transmit
274 try_transmission_to_peer (struct NeighbourMapEntry *n)
276 struct MessageQueue *mq;
277 struct GNUNET_TIME_Relative timeout;
280 if (n->messages_head == NULL)
283 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
284 "Transmission queue for `%4s' is empty\n",
285 GNUNET_i2s (&n->id));
287 return; /* nothing to do */
289 mq = n->messages_head;
290 GNUNET_CONTAINER_DLL_remove (n->messages_head,
293 ret = papi->send (papi->cls,
296 mq->message_buf_size,
298 GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
303 &transmit_send_continuation, mq);
306 /* failure, but 'send' would not call continuation in this case,
307 so we need to do it here! */
308 transmit_send_continuation (mq,
317 * Initialize the neighbours subsystem.
319 * @param cls closure for callbacks
320 * @param connect_cb function to call if we connect to a peer
321 * @param disconnect_cb function to call if we disconnect from a peer
324 GST_neighbours_start (void *cls,
325 GNUNET_TRANSPORT_NotifyConnect connect_cb,
326 GNUNET_TRANSPORT_NotifyDisconnect disconnect_cb)
329 connect_notify_cb = connect_cb;
330 disconnect_notify_cb = disconnect_cb;
331 neighbours = GNUNET_CONTAINER_multihashmap_create (NEIGHBOUR_TABLE_SIZE);
336 * Disconnect from the given neighbour, clean up the record.
338 * @param n neighbour to disconnect from
341 disconnect_neighbour (struct NeighbourMapEntry *n)
343 struct MessageQueue *mq;
347 disconnect_notify_cb (callback_cls,
349 n->is_connected = GNUNET_NO;
351 GNUNET_assert (GNUNET_YES ==
352 GNUNET_CONTAINER_multihashmap_remove (neighbours,
355 while (NULL != (mq = n->messages_head))
357 GNUNET_CONTAINER_DLL_remove (n->messages_head,
364 GNUNET_ATS_suggest_address_cancel (n->asc);
367 GNUNET_array_grow (n->ats,
370 if (NULL != n->plugin_name)
372 GNUNET_free (n->plugin_name);
373 n->plugin_name = NULL;
377 GNUNET_free (n->addr);
387 * Disconnect from the given neighbour.
390 * @param key hash of neighbour's public key (not used)
391 * @param value the 'struct NeighbourMapEntry' of the neighbour
394 disconnect_all_neighbours (void *cls,
395 const GNUNET_HashCode *key,
398 struct NeighbourMapEntry *n = value;
401 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
402 "Disconnecting peer `%4s', %s\n",
406 disconnect_neighbour (n);
412 * Cleanup the neighbours subsystem.
415 GST_neighbours_stop ()
417 GNUNET_CONTAINER_multihashmap_iterate (neighbours,
418 &disconnect_all_neighbours,
420 GNUNET_CONTAINER_multihashmap_destroy (neighbours);
423 connect_notify_cb = NULL;
424 disconnect_notify_cb = NULL;
429 * For an existing neighbour record, set the active connection to
432 * @param plugin_name name of transport that delivered the PONG
433 * @param address address of the other peer, NULL if other peer
435 * @param address_len number of bytes in address
436 * @param ats performance data
437 * @param ats_count number of entries in ats (excluding 0-termination)
440 GST_neighbours_switch_to_address (const struct GNUNET_PeerIdentity *peer,
441 const char *plugin_name,
444 struct Session *session,
445 const struct GNUNET_TRANSPORT_ATS_Information *ats,
448 struct NeighbourMapEntry *n;
450 n = lookup_neighbour (peer);
456 GNUNET_free_non_null (n->addr);
457 n->addr = GNUNET_malloc (address_len);
458 memcpy (n->addr, address, address_len);
459 n->addrlen = address_len;
460 n->session = session;
461 GNUNET_array_grow (n->ats,
466 ats_count * sizeof (struct GNUNET_TRANSPORT_ATS_Information));
467 GNUNET_free_non_null (n->plugin_name);
468 n->plugin_name = GNUNET_strdup (plugin_name);
473 * Try to connect to the target peer using the given address
476 * @param cls the 'struct NeighbourMapEntry' of the target
477 * @param public_key public key for the peer, never NULL
478 * @param target identity of the target peer
479 * @param plugin_name name of the plugin
480 * @param plugin_address binary address
481 * @param plugin_address_len length of address
482 * @param bandwidth available bandwidth
483 * @param ats performance data for the address (as far as known)
484 * @param ats_count number of performance records in 'ats'
487 try_connect_using_address (void *cls,
488 const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *public_key,
489 const struct GNUNET_PeerIdentity *target,
490 const char *plugin_name,
491 const void *plugin_address,
492 size_t plugin_address_len,
493 struct GNUNET_BANDWIDTH_Value32NBO bandwidth,
494 const struct GNUNET_TRANSPORT_ATS_Information *ats,
497 struct NeighbourMapEntry *n = cls;
500 if (n->public_key_valid == GNUNET_NO)
502 n->public_key = *public_key;
503 n->public_key_valid = GNUNET_YES;
505 GST_neighbours_switch_to_address (target,
511 if (GNUNET_YES == n->is_connected)
513 n->is_connected = GNUNET_YES;
514 connect_notify_cb (callback_cls,
522 * We've tried to connect but waited long enough and failed. Clean up.
524 * @param cls the 'struct NeighbourMapEntry' of the neighbour that failed to connect
525 * @param tc scheduler context
528 neighbour_connect_timeout_task (void *cls,
529 const struct GNUNET_SCHEDULER_TaskContext *tc)
531 struct NeighbourMapEntry *n = cls;
533 n->timeout_task = GNUNET_SCHEDULER_NO_TASK;
534 GNUNET_assert (GNUNET_YES ==
535 GNUNET_CONTAINER_multihashmap_remove (neighbours,
538 GNUNET_assert (NULL == n->messages_head);
539 GNUNET_assert (NULL == n->ats);
545 * Try to create a connection to the given target (eventually).
547 * @param target peer to try to connect to
550 GST_neighbours_try_connect (const struct GNUNET_PeerIdentity *target)
552 struct NeighbourMapEntry *n;
554 GNUNET_assert (0 != memcmp (target,
556 sizeof (struct GNUNET_PeerIdentity)));
557 n = lookup_neighbour (target);
559 (GNUNET_YES == n->is_connected) )
560 return; /* already connected */
563 n = GNUNET_malloc (sizeof (struct NeighbourMapEntry));
565 GNUNET_BANDWIDTH_tracker_init (&n->in_tracker,
566 GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT,
567 MAX_BANDWIDTH_CARRY_S);
568 n->timeout_task = GNUNET_SCHEDULER_add_delayed (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
569 &neighbour_connect_timeout_task, n);
570 GNUNET_assert (GNUNET_OK ==
571 GNUNET_CONTAINER_multihashmap_put (neighbours,
574 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
577 return; /* already trying */
578 n->asc = GNUNET_ATS_suggest_address (GST_ats,
580 &try_connect_using_address,
586 * Test if we're connected to the given peer.
588 * @param target peer to test
589 * @return GNUNET_YES if we are connected, GNUNET_NO if not
592 GST_neighbours_test_connected (const struct GNUNET_PeerIdentity *target)
594 struct NeighbourMapEntry *n;
596 n = lookup_neighbour (target);
598 (GNUNET_TIME_absolute_get_remaining (n->peer_timeout).rel_value == 0) )
599 return GNUNET_NO; /* not connected */
605 * Transmit a message to the given target using the active connection.
607 * @param target destination
608 * @param msg message to send
609 * @param msg_size number of bytes in msg
610 * @param timeout when to fail with timeout
611 * @param cont function to call when done
612 * @param cont_cls closure for 'cont'
615 GST_neighbours_send (const struct GNUNET_PeerIdentity *target,
618 struct GNUNET_TIME_Relative timeout,
619 GST_NeighbourSendContinuation cont,
622 struct NeighbourMapEntry *n;
623 struct MessageQueue *mq;
625 n = lookup_neighbour (target);
627 (GNUNET_TIME_absolute_get_remaining (n->peer_timeout).rel_value == 0) )
629 GNUNET_STATISTICS_update (GST_stats,
630 gettext_noop ("# SET QUOTA messages ignored (no such peer)"),
638 GNUNET_assert (msg_size >= sizeof (struct GNUNET_MessageHeader));
639 GNUNET_STATISTICS_update (GST_stats,
640 gettext_noop ("# bytes in message queue for other peers"),
643 mq = GNUNET_malloc (sizeof (struct MessageQueue) + msg_size);
644 /* FIXME: this memcpy can be up to 7% of our total runtime! */
645 memcpy (&mq[1], msg, msg_size);
646 mq->message_buf = (const char*) &mq[1];
647 mq->message_buf_size = msg_size;
648 mq->timeout = GNUNET_TIME_relative_to_absolute (timeout);
649 GNUNET_CONTAINER_DLL_insert_tail (n->messages_head,
652 // try_transmission_to_peer (n);
657 * Change the incoming quota for the given peer.
659 * @param neighbour identity of peer to change qutoa for
660 * @param quota new quota
663 GST_neighbours_set_incoming_quota (const struct GNUNET_PeerIdentity *neighbour,
664 struct GNUNET_BANDWIDTH_Value32NBO quota)
666 struct NeighbourMapEntry *n;
668 n = lookup_neighbour (neighbour);
671 GNUNET_STATISTICS_update (GST_stats,
672 gettext_noop ("# SET QUOTA messages ignored (no such peer)"),
677 GNUNET_BANDWIDTH_tracker_update_quota (&n->in_tracker,
679 if (0 != ntohl (quota.value__))
682 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
683 "Disconnecting peer `%4s' due to `%s'\n",
687 GNUNET_STATISTICS_update (GST_stats,
688 gettext_noop ("# disconnects due to quota of 0"),
691 disconnect_neighbour (n);
696 * Closure for the neighbours_iterate function.
698 struct IteratorContext
701 * Function to call on each connected neighbour.
703 GST_NeighbourIterator cb;
713 * Call the callback from the closure for each connected neighbour.
715 * @param cls the 'struct IteratorContext'
716 * @param key the hash of the public key of the neighbour
717 * @param value the 'struct NeighbourMapEntry'
718 * @return GNUNET_OK (continue to iterate)
721 neighbours_iterate (void *cls,
722 const GNUNET_HashCode *key,
725 struct IteratorContext *ic = cls;
726 struct NeighbourMapEntry *n = value;
728 if (GNUNET_TIME_absolute_get_remaining (n->peer_timeout).rel_value == 0)
729 return GNUNET_OK; /* not connected */
730 GNUNET_assert (n->ats_count > 0);
740 * Iterate over all connected neighbours.
742 * @param cb function to call
743 * @param cb_cls closure for cb
746 GST_neighbours_iterate (GST_NeighbourIterator cb,
749 struct IteratorContext ic;
753 GNUNET_CONTAINER_multihashmap_iterate (neighbours,
760 * Peer has been idle for too long. Disconnect.
762 * @param cls the 'struct NeighbourMapEntry' of the neighbour that went idle
763 * @param tc scheduler context
766 neighbour_idle_timeout_task (void *cls,
767 const struct GNUNET_SCHEDULER_TaskContext *tc)
769 struct NeighbourMapEntry *n = cls;
771 n->timeout_task = GNUNET_SCHEDULER_NO_TASK;
772 disconnect_neighbour (n);
777 * We have received a CONNECT. Set the peer to connected.
779 * @param sender peer sending the PONG
780 * @param hdr the PONG message (presumably)
781 * @param plugin_name name of transport that delivered the PONG
782 * @param sender_address address of the other peer, NULL if other peer
784 * @param sender_address_len number of bytes in sender_address
785 * @param bandwidth bandwidth for the connection
786 * @param ats performance data
787 * @param ats_count number of entries in ats (excluding 0-termination)
788 * @return GNUNET_OK if the message was well-formed, GNUNET_SYSERR if not
791 GST_neighbours_handle_connect (const struct GNUNET_PeerIdentity *sender,
792 const struct GNUNET_MessageHeader *hdr,
793 const char *plugin_name,
794 const void *sender_address,
795 size_t sender_address_len,
796 struct Session *session,
797 const struct GNUNET_TRANSPORT_ATS_Information *ats,
800 struct NeighbourMapEntry *n;
802 if (0 == memcmp (sender,
804 sizeof (struct GNUNET_PeerIdentity)))
807 return GNUNET_SYSERR;
809 n = lookup_neighbour (sender);
811 (n->is_connected == GNUNET_YES) )
812 return GNUNET_OK; /* ats will consider switching and tell us */
815 n = GNUNET_malloc (sizeof (struct NeighbourMapEntry));
817 GNUNET_BANDWIDTH_tracker_init (&n->in_tracker,
818 GNUNET_CONSTANTS_DEFAULT_BW_IN_OUT,
819 MAX_BANDWIDTH_CARRY_S);
820 n->timeout_task = GNUNET_SCHEDULER_add_delayed (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
821 &neighbour_connect_timeout_task, n);
822 GNUNET_assert (GNUNET_OK ==
823 GNUNET_CONTAINER_multihashmap_put (neighbours,
826 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
828 GST_neighbours_switch_to_address (sender,
836 /* inbound bi-directional connection, just use it */
837 n->is_connected = GNUNET_YES;
838 connect_notify_cb (callback_cls,
842 n->peer_timeout = GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT);
843 if (GNUNET_SCHEDULER_NO_TASK != n->timeout_task)
844 GNUNET_SCHEDULER_cancel (n->timeout_task);
845 n->timeout_task = GNUNET_SCHEDULER_add_delayed (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT,
846 &neighbour_idle_timeout_task,
851 /* try to establish our connection back to the initiator */
852 GST_neighbours_try_connect (sender);
859 * If we have an active connection to the given target, it must be shutdown.
861 * @param target peer to disconnect from
864 GST_neighbours_force_disconnect (const struct GNUNET_PeerIdentity *target)
866 struct NeighbourMapEntry *n;
868 n = lookup_neighbour (target);
869 /* FIXME: send disconnect message to target... */
870 disconnect_neighbour (n);
875 * We have received a DISCONNECT. Set the peer to disconnected.
877 * @param sender peer sending the PONG
878 * @param hdr the PONG message (presumably)
879 * @param plugin_name name of transport that delivered the PONG
880 * @param sender_address address of the other peer, NULL if other peer
882 * @param sender_address_len number of bytes in sender_address
883 * @return GNUNET_OK if the message was well-formed, GNUNET_SYSERR if not
886 GST_neighbours_handle_disconnect (const struct GNUNET_PeerIdentity *sender,
887 const struct GNUNET_MessageHeader *hdr,
888 const char *plugin_name,
889 const void *sender_address,
890 size_t sender_address_len)
892 struct NeighbourMapEntry *n;
894 n = lookup_neighbour (sender);
895 /* FIXME: should disconnects have a signature that we should check here? */
896 disconnect_neighbour (n);
901 /* end of file gnunet-service-transport_neighbours.c */