2 This file is part of GNUnet.
3 (C) 2009, 2010, 2011 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 3, or (at your
8 option) any later version.
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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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22 * @file dht/gnunet-service-dht_neighbours.c
23 * @brief GNUnet DHT service's bucket and neighbour management code
24 * @author Christian Grothoff
25 * @author Nathan Evans
29 #include "gnunet_block_lib.h"
30 #include "gnunet_util_lib.h"
31 #include "gnunet_hello_lib.h"
32 #include "gnunet_constants.h"
33 #include "gnunet_protocols.h"
34 #include "gnunet_nse_service.h"
35 #include "gnunet_core_service.h"
36 #include "gnunet_datacache_lib.h"
37 #include "gnunet_transport_service.h"
38 #include "gnunet_hello_lib.h"
39 #include "gnunet_dht_service.h"
40 #include "gnunet_statistics_service.h"
42 #include "gnunet-service-dht.h"
43 #include "gnunet-service-dht_clients.h"
44 #include "gnunet-service-dht_datacache.h"
45 #include "gnunet-service-dht_hello.h"
46 #include "gnunet-service-dht_neighbours.h"
47 #include "gnunet-service-dht_nse.h"
48 #include "gnunet-service-dht_routing.h"
52 * How many buckets will we allow total.
54 #define MAX_BUCKETS sizeof (GNUNET_HashCode) * 8
57 * What is the maximum number of peers in a given bucket.
59 #define DEFAULT_BUCKET_SIZE 4
62 * Size of the bloom filter the DHT uses to filter peers.
64 #define DHT_BLOOM_SIZE 128
67 * Desired replication level for FIND PEER requests
69 #define FIND_PEER_REPLICATION_LEVEL 4
72 * Maximum allowed replication level for all requests.
74 #define MAXIMUM_REPLICATION_LEVEL 16
77 * How often to update our preference levels for peers in our routing tables.
79 #define DHT_DEFAULT_PREFERENCE_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 2)
82 * How long at least to wait before sending another find peer request.
84 #define DHT_MINIMUM_FIND_PEER_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 2)
87 * How long at most to wait before sending another find peer request.
89 #define DHT_MAXIMUM_FIND_PEER_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 8)
92 * How long at most to wait for transmission of a GET request to another peer?
94 #define GET_TIMEOUT GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 2)
100 struct PeerPutMessage
103 * Type: GNUNET_MESSAGE_TYPE_DHT_P2P_PUT
105 struct GNUNET_MessageHeader header;
110 uint32_t options GNUNET_PACKED;
115 uint32_t type GNUNET_PACKED;
120 uint32_t hop_count GNUNET_PACKED;
123 * Replication level for this message
125 uint32_t desired_replication_level GNUNET_PACKED;
128 * Length of the PUT path that follows (if tracked).
130 uint32_t put_path_length GNUNET_PACKED;
133 * When does the content expire?
135 struct GNUNET_TIME_AbsoluteNBO expiration_time;
138 * Bloomfilter (for peer identities) to stop circular routes
140 char bloomfilter[DHT_BLOOM_SIZE];
143 * The key we are storing under.
147 /* put path (if tracked) */
157 struct PeerResultMessage
160 * Type: GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT
162 struct GNUNET_MessageHeader header;
167 uint32_t type GNUNET_PACKED;
170 * Length of the PUT path that follows (if tracked).
172 uint32_t put_path_length GNUNET_PACKED;
175 * Length of the GET path that follows (if tracked).
177 uint32_t get_path_length GNUNET_PACKED;
180 * When does the content expire?
182 struct GNUNET_TIME_AbsoluteNBO expiration_time;
185 * The key of the corresponding GET request.
189 /* put path (if tracked) */
191 /* get path (if tracked) */
201 struct PeerGetMessage
204 * Type: GNUNET_MESSAGE_TYPE_DHT_P2P_GET
206 struct GNUNET_MessageHeader header;
211 uint32_t options GNUNET_PACKED;
214 * Desired content type.
216 uint32_t type GNUNET_PACKED;
221 uint32_t hop_count GNUNET_PACKED;
224 * Desired replication level for this request.
226 uint32_t desired_replication_level GNUNET_PACKED;
229 * Size of the extended query.
231 uint32_t xquery_size;
234 * Bloomfilter mutator.
239 * Bloomfilter (for peer identities) to stop circular routes
241 char bloomfilter[DHT_BLOOM_SIZE];
244 * The key we are looking for.
250 /* result bloomfilter */
256 * Linked list of messages to send to a particular other peer.
258 struct P2PPendingMessage
261 * Pointer to next item in the list
263 struct P2PPendingMessage *next;
266 * Pointer to previous item in the list
268 struct P2PPendingMessage *prev;
271 * Message importance level. FIXME: used? useful?
273 unsigned int importance;
276 * When does this message time out?
278 struct GNUNET_TIME_Absolute timeout;
281 * Actual message to be sent, allocated at the end of the struct:
282 * // msg = (cast) &pm[1];
283 * // memcpy (&pm[1], data, len);
285 const struct GNUNET_MessageHeader *msg;
291 * Entry for a peer in a bucket.
296 * Next peer entry (DLL)
298 struct PeerInfo *next;
301 * Prev peer entry (DLL)
303 struct PeerInfo *prev;
306 * Count of outstanding messages for peer. FIXME: NEEDED?
307 * FIXME: bound queue size!?
309 unsigned int pending_count;
312 * Head of pending messages to be sent to this peer.
314 struct P2PPendingMessage *head;
317 * Tail of pending messages to be sent to this peer.
319 struct P2PPendingMessage *tail;
322 * Core handle for sending messages to this peer.
324 struct GNUNET_CORE_TransmitHandle *th;
327 * Preference update context
329 struct GNUNET_CORE_InformationRequestContext *info_ctx;
332 * Task for scheduling preference updates
334 GNUNET_SCHEDULER_TaskIdentifier preference_task;
337 * What is the identity of the peer?
339 struct GNUNET_PeerIdentity id;
343 * What is the average latency for replies received?
345 struct GNUNET_TIME_Relative latency;
348 * Transport level distance to peer.
350 unsigned int distance;
357 * Peers are grouped into buckets.
364 struct PeerInfo *head;
369 struct PeerInfo *tail;
372 * Number of peers in the bucket.
374 unsigned int peers_size;
379 * The lowest currently used bucket, initially 0 (for 0-bits matching bucket).
381 static unsigned int closest_bucket;
384 * How many peers have we added since we sent out our last
387 static unsigned int newly_found_peers;
390 * The buckets. Array of size MAX_BUCKET_SIZE. Offset 0 means 0 bits matching.
392 static struct PeerBucket k_buckets[MAX_BUCKETS];
395 * Hash map of all known peers, for easy removal from k_buckets on disconnect.
397 static struct GNUNET_CONTAINER_MultiHashMap *all_known_peers;
400 * Maximum size for each bucket.
402 static unsigned int bucket_size = DEFAULT_BUCKET_SIZE;
405 * Task that sends FIND PEER requests.
407 static GNUNET_SCHEDULER_TaskIdentifier find_peer_task;
410 * Identity of this peer.
412 static struct GNUNET_PeerIdentity my_identity;
415 * Handle to GNUnet core.
417 static struct GNUNET_CORE_Handle *coreAPI;
421 * Find the optimal bucket for this key.
423 * @param hc the hashcode to compare our identity to
424 * @return the proper bucket index, or GNUNET_SYSERR
425 * on error (same hashcode)
428 find_bucket (const GNUNET_HashCode * hc)
432 bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, hc);
433 if (bits == MAX_BUCKETS)
435 /* How can all bits match? Got my own ID? */
437 return GNUNET_SYSERR;
439 return MAX_BUCKETS - bits - 1;
444 * Let GNUnet core know that we like the given peer.
446 * @param cls the 'struct PeerInfo' of the peer
447 * @param tc scheduler context.
450 update_core_preference (void *cls,
451 const struct GNUNET_SCHEDULER_TaskContext *tc);
455 * Function called with statistics about the given peer.
458 * @param peer identifies the peer
459 * @param bpm_out set to the current bandwidth limit (sending) for this peer
460 * @param amount set to the amount that was actually reserved or unreserved;
461 * either the full requested amount or zero (no partial reservations)
462 * @param res_delay if the reservation could not be satisfied (amount was 0), how
463 * long should the client wait until re-trying?
464 * @param preference current traffic preference for the given peer
467 update_core_preference_finish (void *cls,
468 const struct GNUNET_PeerIdentity *peer,
469 struct GNUNET_BANDWIDTH_Value32NBO bpm_out,
471 struct GNUNET_TIME_Relative res_delay,
474 struct PeerInfo *peer_info = cls;
476 peer_info->info_ctx = NULL;
477 peer_info->preference_task
478 = GNUNET_SCHEDULER_add_delayed (DHT_DEFAULT_PREFERENCE_INTERVAL,
479 &update_core_preference, peer_info);
484 * Let GNUnet core know that we like the given peer.
486 * @param cls the 'struct PeerInfo' of the peer
487 * @param tc scheduler context.
490 update_core_preference (void *cls,
491 const struct GNUNET_SCHEDULER_TaskContext *tc)
493 struct PeerInfo *peer = cls;
495 unsigned int matching;
498 peer->preference_task = GNUNET_SCHEDULER_NO_TASK;
499 if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
502 GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey,
503 &peer->id.hashPubKey);
506 bucket = find_bucket(&peer->id.hashPubKey);
507 if (bucket == GNUNET_SYSERR)
510 preference = (1LL << matching) / k_buckets[bucket].peers_size;
513 peer->preference_task
514 = GNUNET_SCHEDULER_add_delayed (DHT_DEFAULT_PREFERENCE_INTERVAL,
515 &update_core_preference, peer);
519 GNUNET_CORE_peer_change_preference (coreAPI, &peer->id,
520 GNUNET_TIME_UNIT_FOREVER_REL,
521 GNUNET_BANDWIDTH_VALUE_MAX, 0,
523 &update_core_preference_finish, peer);
528 * Closure for 'add_known_to_bloom'.
530 struct BloomConstructorContext
533 * Bloom filter under construction.
535 struct GNUNET_CONTAINER_BloomFilter *bloom;
545 * Add each of the peers we already know to the bloom filter of
546 * the request so that we don't get duplicate HELLOs.
548 * @param cls the 'struct BloomConstructorContext'.
549 * @param key peer identity to add to the bloom filter
550 * @param value value the peer information (unused)
551 * @return GNUNET_YES (we should continue to iterate)
554 add_known_to_bloom (void *cls, const GNUNET_HashCode * key, void *value)
556 struct BloomConstructorContext *ctx = cls;
559 GNUNET_BLOCK_mingle_hash (key, ctx->bf_mutator, &mh);
560 GNUNET_CONTAINER_bloomfilter_add (ctx->bloom, &mh);
566 * Task to send a find peer message for our own peer identifier
567 * so that we can find the closest peers in the network to ourselves
568 * and attempt to connect to them.
570 * @param cls closure for this task
571 * @param tc the context under which the task is running
574 send_find_peer_message (void *cls,
575 const struct GNUNET_SCHEDULER_TaskContext *tc)
577 struct GNUNET_TIME_Relative next_send_time;
578 struct BloomConstructorContext bcc;
580 find_peer_task = GNUNET_SCHEDULER_NO_TASK;
581 if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
583 if (newly_found_peers > bucket_size)
585 /* If we are finding many peers already, no need to send out our request right now! */
586 find_peer_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES,
587 &send_find_peer_message, NULL);
588 newly_found_peers = 0;
591 bcc.bf_mutator = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, UINT32_MAX);
593 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K);
594 GNUNET_CONTAINER_multihashmap_iterate (all_known_peers,
597 // FIXME: pass priority!?
598 GDS_NEIGHBOURS_handle_get (GNUNET_BLOCK_TYPE_DHT_HELLO,
599 GNUNET_DHT_RO_FIND_PEER,
600 FIND_PEER_REPLICATION_LEVEL,
602 &my_identity.hashPubKey,
604 bcc.bloom, bcc.bf_mutator, NULL);
605 GNUNET_CONTAINER_bloomfilter_free (bcc.bloom);
606 /* schedule next round */
607 newly_found_peers = 0;
608 next_send_time.rel_value =
609 (DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value / 2) +
610 GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_STRONG,
611 DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value / 2);
612 find_peer_task = GNUNET_SCHEDULER_add_delayed (next_send_time,
613 &send_find_peer_message,
619 * Method called whenever a peer connects.
622 * @param peer peer identity this notification is about
623 * @param atsi performance data
626 handle_core_connect (void *cls, const struct GNUNET_PeerIdentity *peer,
627 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
629 struct PeerInfo *ret;
632 /* Check for connect to self message */
633 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
636 GNUNET_CONTAINER_multihashmap_contains (all_known_peers,
642 peer_bucket = find_bucket (&peer->hashPubKey);
643 GNUNET_assert ( (peer_bucket >= 0) && (peer_bucket < MAX_BUCKETS) );
644 ret = GNUNET_malloc (sizeof (struct PeerInfo));
646 ret->latency = latency;
647 ret->distance = distance;
650 GNUNET_CONTAINER_DLL_insert_tail (k_buckets[peer_bucket].head,
651 k_buckets[peer_bucket].tail, ret);
652 k_buckets[peer_bucket].peers_size++;
653 closest_bucket = GNUNET_MAX (closest_bucket,
655 if ( (peer_bucket > 0) &&
656 (k_buckets[peer_bucket].peers_size <= bucket_size) )
657 ret->preference_task = GNUNET_SCHEDULER_add_now (&update_core_preference, ret);
659 GNUNET_assert (GNUNET_OK ==
660 GNUNET_CONTAINER_multihashmap_put (all_known_peers,
661 &peer->hashPubKey, ret,
662 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
663 if (1 == GNUNET_CONTAINER_multihashmap_size (all_known_peers))
665 /* got a first connection, good time to start with FIND PEER requests... */
666 find_peer_task = GNUNET_SCHEDULER_add_now (&send_find_peer_message,
673 * Method called whenever a peer disconnects.
676 * @param peer peer identity this notification is about
679 handle_core_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer)
681 struct PeerInfo *to_remove;
683 struct P2PPendingMessage *pos;
685 /* Check for disconnect from self message */
686 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
689 GNUNET_CONTAINER_multihashmap_get (all_known_peers, &peer->hashPubKey);
690 if (NULL == to_remove)
695 GNUNET_assert (GNUNET_YES ==
696 GNUNET_CONTAINER_multihashmap_remove (all_known_peers,
699 if (NULL != to_remove->info_ctx)
701 GNUNET_CORE_peer_change_preference_cancel (to_remove->info_ctx);
702 to_remove->info_ctx = NULL;
704 current_bucket = find_bucket (&to_remove->id.hashPubKey);
705 GNUNET_CONTAINER_DLL_remove (k_buckets[current_bucket].head,
706 k_buckets[current_bucket].tail,
708 GNUNET_assert (k_buckets[current_bucket].peers_size > 0);
709 k_buckets[current_bucket].peers_size--;
710 while ( (closest_bucket > 0) &&
711 (k_buckets[closest_bucket].peers_size == 0) )
714 if (to_remove->th != NULL)
716 GNUNET_CORE_notify_transmit_ready_cancel (to_remove->th);
717 to_remove->th = NULL;
719 while (NULL != (pos = to_remove->head))
721 GNUNET_CONTAINER_DLL_remove (to_remove->head,
730 * Called when core is ready to send a message we asked for
731 * out to the destination.
733 * @param cls the 'struct PeerInfo' of the target peer
734 * @param size number of bytes available in buf
735 * @param buf where the callee should write the message
736 * @return number of bytes written to buf
739 core_transmit_notify (void *cls, size_t size, void *buf)
741 struct PeerInfo *peer = cls;
743 struct P2PPendingMessage *pending;
750 /* client disconnected */
753 if (peer->head == NULL)
755 /* no messages pending */
759 while ( (NULL != (pending = peer->head)) &&
760 (size - off >= (msize = ntohs (pending->msg->size))) )
762 memcpy (&cbuf[off], pending->msg, msize);
764 peer->pending_count--;
765 GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, pending);
766 GNUNET_free (pending);
768 if (peer->head != NULL)
770 = GNUNET_CORE_notify_transmit_ready (coreAPI, GNUNET_YES,
772 GNUNET_TIME_absolute_get_remaining (pending->timeout),
774 &core_transmit_notify, peer);
780 * Transmit all messages in the peer's message queue.
782 * @param peer message queue to process
785 process_peer_queue (struct PeerInfo *peer)
787 struct P2PPendingMessage *pending;
789 if (NULL != (pending = peer->head))
791 if (NULL != peer->th)
794 = GNUNET_CORE_notify_transmit_ready (coreAPI, GNUNET_YES,
796 GNUNET_TIME_absolute_get_remaining (pending->timeout),
798 ntohs (pending->msg->size),
799 &core_transmit_notify, peer);
804 * To how many peers should we (on average) forward the request to
805 * obtain the desired target_replication count (on average).
807 * @param hop_count number of hops the message has traversed
808 * @param target_replication the number of total paths desired
809 * @return Some number of peers to forward the message to
812 get_forward_count (uint32_t hop_count,
813 uint32_t target_replication)
815 uint32_t random_value;
816 uint32_t forward_count;
819 if (hop_count > GDS_NSE_get () * 4.0)
821 /* forcefully terminate */
824 if (hop_count > GDS_NSE_get () * 2.0)
826 /* Once we have reached our ideal number of hops, only forward to 1 peer */
829 /* bound by system-wide maximum */
830 target_replication = GNUNET_MIN (MAXIMUM_REPLICATION_LEVEL,
833 1 + (target_replication - 1.0) / (GDS_NSE_get () +
834 ((float) (target_replication - 1.0) *
836 /* Set forward count to floor of target_value */
837 forward_count = (uint32_t) target_value;
838 /* Subtract forward_count (floor) from target_value (yields value between 0 and 1) */
839 target_value = target_value - forward_count;
841 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_STRONG, UINT32_MAX);
842 if (random_value < (target_value * UINT32_MAX))
844 return forward_count;
849 * Compute the distance between have and target as a 32-bit value.
850 * Differences in the lower bits must count stronger than differences
851 * in the higher bits.
853 * @return 0 if have==target, otherwise a number
854 * that is larger as the distance between
855 * the two hash codes increases
858 get_distance (const GNUNET_HashCode * target, const GNUNET_HashCode * have)
865 /* We have to represent the distance between two 2^9 (=512)-bit
866 * numbers as a 2^5 (=32)-bit number with "0" being used for the
867 * two numbers being identical; furthermore, we need to
868 * guarantee that a difference in the number of matching
869 * bits is always represented in the result.
871 * We use 2^32/2^9 numerical values to distinguish between
872 * hash codes that have the same LSB bit distance and
873 * use the highest 2^9 bits of the result to signify the
874 * number of (mis)matching LSB bits; if we have 0 matching
875 * and hence 512 mismatching LSB bits we return -1 (since
876 * 512 itself cannot be represented with 9 bits) */
878 /* first, calculate the most significant 9 bits of our
879 * result, aka the number of LSBs */
880 bucket = GNUNET_CRYPTO_hash_matching_bits (target, have);
881 /* bucket is now a value between 0 and 512 */
883 return 0; /* perfect match */
885 return (unsigned int) -1; /* LSB differs; use max (if we did the bit-shifting
886 * below, we'd end up with max+1 (overflow)) */
888 /* calculate the most significant bits of the final result */
889 msb = (512 - bucket) << (32 - 9);
890 /* calculate the 32-9 least significant bits of the final result by
891 * looking at the differences in the 32-9 bits following the
892 * mismatching bit at 'bucket' */
895 (i < sizeof (GNUNET_HashCode) * 8) && (i < bucket + 1 + 32 - 9); i++)
897 if (GNUNET_CRYPTO_hash_get_bit (target, i) !=
898 GNUNET_CRYPTO_hash_get_bit (have, i))
899 lsb |= (1 << (bucket + 32 - 9 - i)); /* first bit set will be 10,
900 * last bit set will be 31 -- if
901 * i does not reach 512 first... */
908 * Check whether my identity is closer than any known peers. If a
909 * non-null bloomfilter is given, check if this is the closest peer
910 * that hasn't already been routed to.
912 * @param key hash code to check closeness to
913 * @param bloom bloomfilter, exclude these entries from the decision
914 * @return GNUNET_YES if node location is closest,
915 * GNUNET_NO otherwise.
918 am_closest_peer (const GNUNET_HashCode *key,
919 const struct GNUNET_CONTAINER_BloomFilter *bloom)
925 struct PeerInfo *pos;
926 unsigned int my_distance;
928 if (0 == memcmp (&my_identity.hashPubKey, key, sizeof (GNUNET_HashCode)))
930 bucket_num = find_bucket (key);
931 bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, key);
932 my_distance = get_distance (&my_identity.hashPubKey, key);
933 pos = k_buckets[bucket_num].head;
935 while ((pos != NULL) && (count < bucket_size))
937 if ((bloom != NULL) &&
939 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)))
942 continue; /* Skip already checked entries */
944 other_bits = GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey, key);
945 if (other_bits > bits)
947 if (other_bits == bits) /* We match the same number of bits */
951 /* No peers closer, we are the closest! */
957 * Select a peer from the routing table that would be a good routing
958 * destination for sending a message for "key". The resulting peer
959 * must not be in the set of blocked peers.<p>
961 * Note that we should not ALWAYS select the closest peer to the
962 * target, peers further away from the target should be chosen with
963 * exponentially declining probability.
965 * FIXME: double-check that this is fine
968 * @param key the key we are selecting a peer to route to
969 * @param bloom a bloomfilter containing entries this request has seen already
970 * @param hops how many hops has this message traversed thus far
971 * @return Peer to route to, or NULL on error
973 static struct PeerInfo *
974 select_peer (const GNUNET_HashCode *key,
975 const struct GNUNET_CONTAINER_BloomFilter *bloom,
980 unsigned int selected;
981 struct PeerInfo *pos;
983 unsigned int smallest_distance;
984 struct PeerInfo *chosen;
986 if (hops >= GDS_NSE_get ())
988 /* greedy selection (closest peer that is not in bloomfilter) */
989 smallest_distance = UINT_MAX;
991 for (bc = closest_bucket; bc < MAX_BUCKETS; bc++)
993 pos = k_buckets[bc].head;
995 while ((pos != NULL) && (count < bucket_size))
998 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey))
1000 dist = get_distance (key, &pos->id.hashPubKey);
1001 if (dist < smallest_distance)
1004 smallest_distance = dist;
1014 /* select "random" peer */
1015 /* count number of peers that are available and not filtered */
1017 for (bc = closest_bucket; bc < MAX_BUCKETS; bc++)
1019 pos = k_buckets[bc].head;
1020 while ((pos != NULL) && (count < bucket_size))
1023 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey))
1026 continue; /* Ignore bloomfiltered peers */
1032 if (count == 0) /* No peers to select from! */
1036 /* Now actually choose a peer */
1037 selected = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, count);
1039 for (bc = closest_bucket; bc < MAX_BUCKETS; bc++)
1041 pos = k_buckets[bc].head;
1042 while ((pos != NULL) && (count < bucket_size))
1045 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey))
1048 continue; /* Ignore bloomfiltered peers */
1050 if (0 == selected--)
1061 * Compute the set of peers that the given request should be
1064 * @param key routing key
1065 * @param bloom bloom filter excluding peers as targets, all selected
1066 * peers will be added to the bloom filter
1067 * @param hop_count number of hops the request has traversed so far
1068 * @param target_replication desired number of replicas
1069 * @param targets where to store an array of target peers (to be
1070 * free'd by the caller)
1071 * @return number of peers returned in 'targets'.
1074 get_target_peers (const GNUNET_HashCode *key,
1075 struct GNUNET_CONTAINER_BloomFilter *bloom,
1077 uint32_t target_replication,
1078 struct PeerInfo ***targets)
1082 struct PeerInfo **rtargets;
1083 struct PeerInfo *nxt;
1085 ret = get_forward_count (hop_count, target_replication);
1091 rtargets = GNUNET_malloc (sizeof (struct PeerInfo*) * ret);
1095 nxt = select_peer (key, bloom, hop_count);
1098 rtargets[off++] = nxt;
1099 GNUNET_CONTAINER_bloomfilter_add (bloom, &nxt->id.hashPubKey);
1103 GNUNET_free (rtargets);
1107 *targets = rtargets;
1113 * Perform a PUT operation. Forwards the given request to other
1114 * peers. Does not store the data locally. Does not give the
1115 * data to local clients. May do nothing if this is the only
1116 * peer in the network (or if we are the closest peer in the
1119 * @param type type of the block
1120 * @param options routing options
1121 * @param desired_replication_level desired replication count
1122 * @param expiration_time when does the content expire
1123 * @param hop_count how many hops has this message traversed so far
1124 * @param bf Bloom filter of peers this PUT has already traversed
1125 * @param key key for the content
1126 * @param put_path_length number of entries in put_path
1127 * @param put_path peers this request has traversed so far (if tracked)
1128 * @param data payload to store
1129 * @param data_size number of bytes in data
1132 GDS_NEIGHBOURS_handle_put (enum GNUNET_BLOCK_Type type,
1133 enum GNUNET_DHT_RouteOption options,
1134 uint32_t desired_replication_level,
1135 struct GNUNET_TIME_Absolute expiration_time,
1137 struct GNUNET_CONTAINER_BloomFilter *bf,
1138 const GNUNET_HashCode *key,
1139 unsigned int put_path_length,
1140 struct GNUNET_PeerIdentity *put_path,
1144 unsigned int target_count;
1146 struct PeerInfo **targets;
1147 struct PeerInfo *target;
1148 struct P2PPendingMessage *pending;
1150 struct PeerPutMessage *ppm;
1151 struct GNUNET_PeerIdentity *pp;
1153 target_count = get_target_peers (key, bf, hop_count,
1154 desired_replication_level,
1156 if (0 == target_count)
1158 msize = put_path_length * sizeof (struct GNUNET_PeerIdentity) + data_size + sizeof (struct PeerPutMessage);
1159 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1161 put_path_length = 0;
1162 msize = data_size + sizeof (struct PeerPutMessage);
1164 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1169 for (i=0;i<target_count;i++)
1171 target = targets[i];
1172 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1173 pending->importance = 0; /* FIXME */
1174 pending->timeout = expiration_time;
1175 ppm = (struct PeerPutMessage*) &pending[1];
1176 pending->msg = &ppm->header;
1177 ppm->header.size = htons (msize);
1178 ppm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_PUT);
1179 ppm->options = htonl (options);
1180 ppm->type = htonl (type);
1181 ppm->hop_count = htonl (hop_count + 1);
1182 ppm->desired_replication_level = htonl (desired_replication_level);
1183 ppm->put_path_length = htonl (put_path_length);
1184 ppm->expiration_time = GNUNET_TIME_absolute_hton (expiration_time);
1185 GNUNET_assert (GNUNET_OK ==
1186 GNUNET_CONTAINER_bloomfilter_get_raw_data (bf,
1190 pp = (struct GNUNET_PeerIdentity*) &ppm[1];
1191 memcpy (pp, put_path, sizeof (struct GNUNET_PeerIdentity) * put_path_length);
1192 memcpy (&pp[put_path_length], data, data_size);
1193 GNUNET_CONTAINER_DLL_insert_tail (target->head,
1196 target->pending_count++;
1197 process_peer_queue (target);
1199 GNUNET_free (targets);
1204 * Perform a GET operation. Forwards the given request to other
1205 * peers. Does not lookup the key locally. May do nothing if this is
1206 * the only peer in the network (or if we are the closest peer in the
1209 * @param type type of the block
1210 * @param options routing options
1211 * @param desired_replication_level desired replication count
1212 * @param hop_count how many hops did this request traverse so far?
1213 * @param key key for the content
1214 * @param xquery extended query
1215 * @param xquery_size number of bytes in xquery
1216 * @param reply_bf bloomfilter to filter duplicates
1217 * @param reply_bf_mutator mutator for reply_bf
1218 * @param peer_bf filter for peers not to select (again)
1221 GDS_NEIGHBOURS_handle_get (enum GNUNET_BLOCK_Type type,
1222 enum GNUNET_DHT_RouteOption options,
1223 uint32_t desired_replication_level,
1225 const GNUNET_HashCode *key,
1228 const struct GNUNET_CONTAINER_BloomFilter *reply_bf,
1229 uint32_t reply_bf_mutator,
1230 struct GNUNET_CONTAINER_BloomFilter *peer_bf)
1232 unsigned int target_count;
1234 struct PeerInfo **targets;
1235 struct PeerInfo *target;
1236 struct P2PPendingMessage *pending;
1238 struct PeerGetMessage *pgm;
1240 size_t reply_bf_size;
1242 target_count = get_target_peers (key, peer_bf, hop_count,
1243 desired_replication_level,
1245 if (0 == target_count)
1247 reply_bf_size = GNUNET_CONTAINER_bloomfilter_get_size (reply_bf);
1248 msize = xquery_size + sizeof (struct PeerGetMessage) + reply_bf_size;
1249 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1254 /* forward request */
1255 for (i=0;i<target_count;i++)
1257 target = targets[i];
1258 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1259 pending->importance = 0; /* FIXME */
1260 pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
1261 pgm = (struct PeerGetMessage*) &pending[1];
1262 pending->msg = &pgm->header;
1263 pgm->header.size = htons (msize);
1264 pgm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_GET);
1265 pgm->options = htonl (options);
1266 pgm->type = htonl (type);
1267 pgm->hop_count = htonl (hop_count + 1);
1268 pgm->desired_replication_level = htonl (desired_replication_level);
1269 pgm->xquery_size = htonl (xquery_size);
1270 pgm->bf_mutator = reply_bf_mutator;
1271 GNUNET_assert (GNUNET_OK ==
1272 GNUNET_CONTAINER_bloomfilter_get_raw_data (peer_bf,
1276 xq = (char *) &pgm[1];
1277 memcpy (xq, xquery, xquery_size);
1278 GNUNET_assert (GNUNET_OK ==
1279 GNUNET_CONTAINER_bloomfilter_get_raw_data (reply_bf,
1282 GNUNET_CONTAINER_DLL_insert_tail (target->head,
1285 target->pending_count++;
1286 process_peer_queue (target);
1288 GNUNET_free (targets);
1293 * Handle a reply (route to origin). Only forwards the reply back to
1294 * the given peer. Does not do local caching or forwarding to local
1297 * @param target neighbour that should receive the block (if still connected)
1298 * @param type type of the block
1299 * @param expiration_time when does the content expire
1300 * @param key key for the content
1301 * @param put_path_length number of entries in put_path
1302 * @param put_path peers the original PUT traversed (if tracked)
1303 * @param get_path_length number of entries in put_path
1304 * @param get_path peers this reply has traversed so far (if tracked)
1305 * @param data payload of the reply
1306 * @param data_size number of bytes in data
1309 GDS_NEIGHBOURS_handle_reply (const struct GNUNET_PeerIdentity *target,
1310 enum GNUNET_BLOCK_Type type,
1311 struct GNUNET_TIME_Absolute expiration_time,
1312 const GNUNET_HashCode *key,
1313 unsigned int put_path_length,
1314 const struct GNUNET_PeerIdentity *put_path,
1315 unsigned int get_path_length,
1316 const struct GNUNET_PeerIdentity *get_path,
1320 struct PeerInfo *pi;
1321 struct P2PPendingMessage *pending;
1323 struct PeerResultMessage *prm;
1324 struct GNUNET_PeerIdentity *paths;
1326 msize = data_size + sizeof (struct PeerResultMessage) +
1327 (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity);
1328 if ( (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE) ||
1329 (get_path_length > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
1330 (put_path_length > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
1331 (data_size > GNUNET_SERVER_MAX_MESSAGE_SIZE) )
1336 pi = GNUNET_CONTAINER_multihashmap_get (all_known_peers,
1337 &target->hashPubKey);
1340 /* peer disconnected in the meantime, drop reply */
1343 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1344 pending->importance = 0; /* FIXME */
1345 pending->timeout = expiration_time;
1346 prm = (struct PeerResultMessage*) &pending[1];
1347 pending->msg = &prm->header;
1348 prm->header.size = htons (msize);
1349 prm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT);
1350 prm->type = htonl (type);
1351 prm->put_path_length = htonl (put_path_length);
1352 prm->get_path_length = htonl (get_path_length);
1353 prm->expiration_time = GNUNET_TIME_absolute_hton (expiration_time);
1355 paths = (struct GNUNET_PeerIdentity*) &prm[1];
1356 memcpy (paths, put_path, put_path_length * sizeof (struct GNUNET_PeerIdentity));
1357 memcpy (&paths[put_path_length],
1358 get_path, get_path_length * sizeof (struct GNUNET_PeerIdentity));
1359 memcpy (&paths[put_path_length + get_path_length],
1361 GNUNET_CONTAINER_DLL_insert (pi->head,
1364 pi->pending_count++;
1365 process_peer_queue (pi);
1370 * To be called on core init/fail.
1372 * @param cls service closure
1373 * @param server handle to the server for this service
1374 * @param identity the public identity of this peer
1375 * @param publicKey the public key of this peer
1378 core_init (void *cls, struct GNUNET_CORE_Handle *server,
1379 const struct GNUNET_PeerIdentity *identity,
1380 const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *publicKey)
1382 GNUNET_assert (server != NULL);
1383 my_identity = *identity;
1388 * Core handler for p2p put requests.
1390 * @param cls closure
1391 * @param peer sender of the request
1392 * @param message message
1393 * @param peer peer identity this notification is about
1394 * @param atsi performance data
1395 * @return GNUNET_OK to keep the connection open,
1396 * GNUNET_SYSERR to close it (signal serious error)
1399 handle_dht_p2p_put (void *cls,
1400 const struct GNUNET_PeerIdentity *peer,
1401 const struct GNUNET_MessageHeader *message,
1402 const struct GNUNET_TRANSPORT_ATS_Information
1405 const struct PeerPutMessage *put;
1406 const struct GNUNET_PeerIdentity *put_path;
1407 const void *payload;
1410 size_t payload_size;
1411 enum GNUNET_DHT_RouteOption options;
1412 struct GNUNET_CONTAINER_BloomFilter *bf;
1413 GNUNET_HashCode test_key;
1415 msize = ntohs (message->size);
1416 if (msize < sizeof (struct PeerPutMessage))
1418 GNUNET_break_op (0);
1421 put = (const struct PeerPutMessage*) message;
1422 putlen = ntohl (put->put_path_length);
1423 if ( (msize < sizeof (struct PeerPutMessage) + putlen * sizeof (struct GNUNET_PeerIdentity)) ||
1424 (putlen > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) )
1426 GNUNET_break_op (0);
1429 put_path = (const struct GNUNET_PeerIdentity*) &put[1];
1430 payload = &put_path[putlen];
1431 options = ntohl (put->options);
1432 payload_size = msize - (sizeof (struct PeerPutMessage) +
1433 putlen * sizeof (struct GNUNET_PeerIdentity));
1434 switch (GNUNET_BLOCK_get_key (GDS_block_context,
1436 payload, payload_size,
1440 if (0 != memcmp (&test_key, &put->key, sizeof (GNUNET_HashCode)))
1442 GNUNET_break_op (0);
1447 GNUNET_break_op (0);
1450 /* cannot verify, good luck */
1453 bf = GNUNET_CONTAINER_bloomfilter_init (put->bloomfilter,
1457 struct GNUNET_PeerIdentity pp[putlen+1];
1459 /* extend 'put path' by sender */
1460 if (0 != (options & GNUNET_DHT_RO_RECORD_ROUTE))
1462 memcpy (pp, put_path, putlen * sizeof (struct GNUNET_PeerIdentity));
1469 /* give to local clients */
1470 GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (put->expiration_time),
1479 if ( (0 != (options & GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE)) ||
1480 (am_closest_peer (&put->key,
1482 GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (put->expiration_time),
1488 /* route to other peers */
1489 GDS_NEIGHBOURS_handle_put (ntohl (put->type),
1491 ntohl (put->desired_replication_level),
1492 GNUNET_TIME_absolute_ntoh (put->expiration_time),
1493 ntohl (put->hop_count) + 1 /* who adds +1? */,
1500 GNUNET_CONTAINER_bloomfilter_free (bf);
1506 * We have received a FIND PEER request. Send matching
1509 * @param sender sender of the FIND PEER request
1510 * @param key peers close to this key are desired
1511 * @param bf peers matching this bf are excluded
1512 * @param bf_mutator mutator for bf
1515 handle_find_peer (const struct GNUNET_PeerIdentity *sender,
1516 const GNUNET_HashCode *key,
1517 struct GNUNET_CONTAINER_BloomFilter *bf,
1518 uint32_t bf_mutator)
1521 struct PeerBucket *bucket;
1522 struct PeerInfo *peer;
1523 unsigned int choice;
1524 GNUNET_HashCode mhash;
1525 const struct GNUNET_HELLO_Message *hello;
1527 /* first, check about our own HELLO */
1528 if (NULL != GDS_my_hello)
1530 GNUNET_BLOCK_mingle_hash (&my_identity.hashPubKey, bf_mutator, &mhash);
1531 if (GNUNET_YES != GNUNET_CONTAINER_bloomfilter_test (bf, &mhash))
1533 GDS_NEIGHBOURS_handle_reply (sender,
1534 GNUNET_BLOCK_TYPE_DHT_HELLO,
1535 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_HELLO_ADDRESS_EXPIRATION),
1540 GNUNET_HELLO_size ((const struct GNUNET_HELLO_Message*) GDS_my_hello));
1543 /* then, also consider sending a random HELLO from the closest bucket */
1544 bucket_idx = find_bucket (key);
1545 if (bucket_idx == GNUNET_SYSERR)
1547 bucket = &k_buckets[bucket_idx];
1548 if (bucket->peers_size == 0)
1550 choice = GNUNET_CRYPTO_random_u32 (bucket->peers_size,
1551 GNUNET_CRYPTO_QUALITY_WEAK);
1552 peer = bucket->head;
1555 GNUNET_assert (peer != NULL);
1558 choice = bucket->peers_size;
1563 return; /* no non-masked peer available */
1565 peer = bucket->head;
1566 GNUNET_BLOCK_mingle_hash (&peer->id.hashPubKey, bf_mutator, &mhash);
1567 hello = GDS_HELLO_get (&peer->id);
1569 while ( (hello == NULL) ||
1570 (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bf, &mhash)) );
1571 GDS_NEIGHBOURS_handle_reply (sender,
1572 GNUNET_BLOCK_TYPE_DHT_HELLO,
1573 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_HELLO_ADDRESS_EXPIRATION),
1578 GNUNET_HELLO_size (hello));
1583 * Core handler for p2p get requests.
1585 * @param cls closure
1586 * @param peer sender of the request
1587 * @param message message
1588 * @param peer peer identity this notification is about
1589 * @param atsi performance data
1590 * @return GNUNET_OK to keep the connection open,
1591 * GNUNET_SYSERR to close it (signal serious error)
1594 handle_dht_p2p_get (void *cls, const struct GNUNET_PeerIdentity *peer,
1595 const struct GNUNET_MessageHeader *message,
1596 const struct GNUNET_TRANSPORT_ATS_Information
1599 struct PeerGetMessage *get;
1600 uint32_t xquery_size;
1601 size_t reply_bf_size;
1603 enum GNUNET_BLOCK_Type type;
1604 enum GNUNET_DHT_RouteOption options;
1605 enum GNUNET_BLOCK_EvaluationResult eval;
1606 struct GNUNET_CONTAINER_BloomFilter *reply_bf;
1607 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
1610 /* parse and validate message */
1611 msize = ntohs (message->size);
1612 if (msize < sizeof (struct PeerGetMessage))
1614 GNUNET_break_op (0);
1617 get = (struct PeerGetMessage *) message;
1618 xquery_size = ntohl (get->xquery_size);
1619 if (msize < sizeof (struct PeerGetMessage) + xquery_size)
1621 GNUNET_break_op (0);
1624 reply_bf_size = msize - (sizeof (struct PeerGetMessage) + xquery_size);
1625 type = ntohl (get->type);
1626 options = ntohl (get->options);
1627 xquery = (const char*) &get[1];
1629 if (reply_bf_size > 0)
1630 reply_bf = GNUNET_CONTAINER_bloomfilter_init (&xquery[xquery_size],
1632 GNUNET_DHT_GET_BLOOMFILTER_K);
1633 eval = GNUNET_BLOCK_evaluate (GDS_block_context,
1638 xquery, xquery_size,
1640 if (eval != GNUNET_BLOCK_EVALUATION_REQUEST_VALID)
1642 /* request invalid or block type not supported */
1643 GNUNET_break_op (eval == GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED);
1644 if (NULL != reply_bf)
1645 GNUNET_CONTAINER_bloomfilter_free (reply_bf);
1649 GNUNET_CONTAINER_bloomfilter_init (get->bloomfilter,
1653 /* remember request for routing replies */
1654 GDS_ROUTING_add (peer,
1658 xquery, xquery_size,
1659 reply_bf, get->bf_mutator);
1661 /* local lookup (this may update the reply_bf) */
1662 if ( (0 != (options & GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE)) ||
1663 (am_closest_peer (&get->key,
1666 if ( (0 != (options & GNUNET_DHT_RO_FIND_PEER)))
1668 handle_find_peer (peer,
1675 eval = GDS_DATACACHE_handle_get (&get->key,
1677 xquery, xquery_size,
1683 /* P2P forwarding */
1684 if (eval != GNUNET_BLOCK_EVALUATION_OK_LAST)
1685 GDS_NEIGHBOURS_handle_get (type,
1687 ntohl (get->desired_replication_level),
1688 ntohl (get->hop_count) + 1, /* CHECK: where (else) do we do +1? */
1690 xquery, xquery_size,
1695 if (NULL != reply_bf)
1696 GNUNET_CONTAINER_bloomfilter_free (reply_bf);
1697 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
1703 * Core handler for p2p result messages.
1705 * @param cls closure
1706 * @param message message
1707 * @param peer peer identity this notification is about
1708 * @param atsi performance data
1709 * @return GNUNET_YES (do not cut p2p connection)
1712 handle_dht_p2p_result (void *cls, const struct GNUNET_PeerIdentity *peer,
1713 const struct GNUNET_MessageHeader *message,
1714 const struct GNUNET_TRANSPORT_ATS_Information
1717 const struct PeerResultMessage *prm;
1718 const struct GNUNET_PeerIdentity *put_path;
1719 const struct GNUNET_PeerIdentity *get_path;
1721 uint32_t get_path_length;
1722 uint32_t put_path_length;
1725 enum GNUNET_BLOCK_Type type;
1727 /* parse and validate message */
1728 msize = ntohs (message->size);
1729 if (msize < sizeof (struct PeerResultMessage))
1731 GNUNET_break_op (0);
1734 prm = (struct PeerResultMessage *) message;
1735 put_path_length = ntohl (prm->put_path_length);
1736 get_path_length = ntohl (prm->get_path_length);
1737 if ( (msize < sizeof (struct PeerResultMessage) +
1738 (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity)) ||
1739 (get_path_length > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
1740 (put_path_length > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) )
1742 GNUNET_break_op (0);
1745 put_path = (const struct GNUNET_PeerIdentity*) &prm[1];
1746 get_path = &put_path[put_path_length];
1747 type = ntohl (prm->type);
1748 data = (const void*) &get_path[get_path_length];
1749 data_size = msize - (sizeof (struct PeerResultMessage) +
1750 (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity));
1752 /* if we got a HELLO, consider it for our own routing table */
1753 if (type == GNUNET_BLOCK_TYPE_DHT_HELLO)
1755 const struct GNUNET_MessageHeader *h;
1756 struct GNUNET_PeerIdentity pid;
1759 /* Should be a HELLO, validate and consider using it! */
1760 if (data_size < sizeof (struct GNUNET_MessageHeader))
1762 GNUNET_break_op (0);
1766 if (data_size != ntohs (h->size))
1768 GNUNET_break_op (0);
1772 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message*) h,
1775 GNUNET_break_op (0);
1778 bucket = find_bucket (&pid.hashPubKey);
1779 if ( (bucket >= 0) &&
1780 (k_buckets[bucket].peers_size < bucket_size) )
1782 if (NULL != GDS_transport_handle)
1783 GNUNET_TRANSPORT_offer_hello (GDS_transport_handle,
1785 (void) GNUNET_CORE_peer_request_connect (coreAPI,
1791 /* append 'peer' to 'get_path' */
1793 struct GNUNET_PeerIdentity xget_path[get_path_length+1];
1795 memcpy (xget_path, get_path, get_path_length * sizeof (struct GNUNET_PeerIdentity));
1796 xget_path[get_path_length] = *peer;
1799 /* forward to local clients */
1800 GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (prm->expiration_time),
1810 /* forward to other peers */
1811 GDS_ROUTING_process (type,
1812 GNUNET_TIME_absolute_ntoh (prm->expiration_time),
1826 * Initialize neighbours subsystem.
1828 * @return GNUNET_OK on success, GNUNET_SYSERR on error
1831 GDS_NEIGHBOURS_init ()
1833 static struct GNUNET_CORE_MessageHandler core_handlers[] = {
1834 {&handle_dht_p2p_get, GNUNET_MESSAGE_TYPE_DHT_P2P_GET, 0},
1835 {&handle_dht_p2p_put, GNUNET_MESSAGE_TYPE_DHT_P2P_PUT, 0},
1836 {&handle_dht_p2p_result, GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT, 0},
1839 unsigned long long temp_config_num;
1842 GNUNET_CONFIGURATION_get_value_number (GDS_cfg, "DHT", "bucket_size",
1844 bucket_size = (unsigned int) temp_config_num;
1845 coreAPI = GNUNET_CORE_connect (GDS_cfg,
1849 &handle_core_connect,
1850 &handle_core_disconnect,
1851 NULL, /* Do we care about "status" updates? */
1855 if (coreAPI == NULL)
1856 return GNUNET_SYSERR;
1857 all_known_peers = GNUNET_CONTAINER_multihashmap_create (256);
1863 * Shutdown neighbours subsystem.
1866 GDS_NEIGHBOURS_done ()
1868 if (coreAPI == NULL)
1870 GNUNET_CORE_disconnect (coreAPI);
1872 GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (all_known_peers));
1873 GNUNET_CONTAINER_multihashmap_destroy (all_known_peers);
1874 all_known_peers = NULL;
1875 if (GNUNET_SCHEDULER_NO_TASK != find_peer_task)
1877 GNUNET_SCHEDULER_cancel (find_peer_task);
1878 find_peer_task = GNUNET_SCHEDULER_NO_TASK;
1883 /* end of gnunet-service-dht_neighbours.c */