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.
15 You should have received a copy of the GNU General Public License
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17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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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"
41 #include "gnunet-service-dht.h"
42 #include "gnunet-service-dht_clients.h"
43 #include "gnunet-service-dht_datacache.h"
44 #include "gnunet-service-dht_hello.h"
45 #include "gnunet-service-dht_neighbours.h"
46 #include "gnunet-service-dht_nse.h"
47 #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 * Desired replication level for FIND PEER requests
64 #define FIND_PEER_REPLICATION_LEVEL 4
67 * Maximum allowed replication level for all requests.
69 #define MAXIMUM_REPLICATION_LEVEL 16
72 * How often to update our preference levels for peers in our routing tables.
74 #define DHT_DEFAULT_PREFERENCE_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 2)
77 * How long at least to wait before sending another find peer request.
79 #define DHT_MINIMUM_FIND_PEER_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 2)
82 * How long at most to wait before sending another find peer request.
84 #define DHT_MAXIMUM_FIND_PEER_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 8)
87 * How long at most to wait for transmission of a GET request to another peer?
89 #define GET_TIMEOUT GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 2)
98 * Type: GNUNET_MESSAGE_TYPE_DHT_P2P_PUT
100 struct GNUNET_MessageHeader header;
105 uint32_t options GNUNET_PACKED;
110 uint32_t type GNUNET_PACKED;
115 uint32_t hop_count GNUNET_PACKED;
118 * Replication level for this message
120 uint32_t desired_replication_level GNUNET_PACKED;
123 * Length of the PUT path that follows (if tracked).
125 uint32_t put_path_length GNUNET_PACKED;
128 * When does the content expire?
130 struct GNUNET_TIME_AbsoluteNBO expiration_time;
133 * Bloomfilter (for peer identities) to stop circular routes
135 char bloomfilter[DHT_BLOOM_SIZE];
138 * The key we are storing under.
142 /* put path (if tracked) */
152 struct PeerResultMessage
155 * Type: GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT
157 struct GNUNET_MessageHeader header;
162 uint32_t type GNUNET_PACKED;
165 * Length of the PUT path that follows (if tracked).
167 uint32_t put_path_length GNUNET_PACKED;
170 * Length of the GET path that follows (if tracked).
172 uint32_t get_path_length GNUNET_PACKED;
175 * When does the content expire?
177 struct GNUNET_TIME_AbsoluteNBO expiration_time;
180 * The key of the corresponding GET request.
184 /* put path (if tracked) */
186 /* get path (if tracked) */
196 struct PeerGetMessage
199 * Type: GNUNET_MESSAGE_TYPE_DHT_P2P_GET
201 struct GNUNET_MessageHeader header;
206 uint32_t options GNUNET_PACKED;
209 * Desired content type.
211 uint32_t type GNUNET_PACKED;
216 uint32_t hop_count GNUNET_PACKED;
219 * Desired replication level for this request.
221 uint32_t desired_replication_level GNUNET_PACKED;
224 * Size of the extended query.
226 uint32_t xquery_size;
229 * Bloomfilter mutator.
234 * Bloomfilter (for peer identities) to stop circular routes
236 char bloomfilter[DHT_BLOOM_SIZE];
239 * The key we are looking for.
245 /* result bloomfilter */
251 * Linked list of messages to send to a particular other peer.
253 struct P2PPendingMessage
256 * Pointer to next item in the list
258 struct P2PPendingMessage *next;
261 * Pointer to previous item in the list
263 struct P2PPendingMessage *prev;
266 * Message importance level. FIXME: used? useful?
268 unsigned int importance;
271 * When does this message time out?
273 struct GNUNET_TIME_Absolute timeout;
276 * Actual message to be sent, allocated at the end of the struct:
277 * // msg = (cast) &pm[1];
278 * // memcpy (&pm[1], data, len);
280 const struct GNUNET_MessageHeader *msg;
286 * Entry for a peer in a bucket.
291 * Next peer entry (DLL)
293 struct PeerInfo *next;
296 * Prev peer entry (DLL)
298 struct PeerInfo *prev;
301 * Count of outstanding messages for peer. FIXME: NEEDED?
302 * FIXME: bound queue size!?
304 unsigned int pending_count;
307 * Head of pending messages to be sent to this peer.
309 struct P2PPendingMessage *head;
312 * Tail of pending messages to be sent to this peer.
314 struct P2PPendingMessage *tail;
317 * Core handle for sending messages to this peer.
319 struct GNUNET_CORE_TransmitHandle *th;
322 * Preference update context
324 struct GNUNET_CORE_InformationRequestContext *info_ctx;
327 * Task for scheduling preference updates
329 GNUNET_SCHEDULER_TaskIdentifier preference_task;
332 * What is the identity of the peer?
334 struct GNUNET_PeerIdentity id;
338 * What is the average latency for replies received?
340 struct GNUNET_TIME_Relative latency;
343 * Transport level distance to peer.
345 unsigned int distance;
352 * Peers are grouped into buckets.
359 struct PeerInfo *head;
364 struct PeerInfo *tail;
367 * Number of peers in the bucket.
369 unsigned int peers_size;
374 * The lowest currently used bucket, initially 0 (for 0-bits matching bucket).
376 static unsigned int closest_bucket;
379 * How many peers have we added since we sent out our last
382 static unsigned int newly_found_peers;
385 * The buckets. Array of size MAX_BUCKET_SIZE. Offset 0 means 0 bits matching.
387 static struct PeerBucket k_buckets[MAX_BUCKETS];
390 * Hash map of all known peers, for easy removal from k_buckets on disconnect.
392 static struct GNUNET_CONTAINER_MultiHashMap *all_known_peers;
395 * Maximum size for each bucket.
397 static unsigned int bucket_size = DEFAULT_BUCKET_SIZE;
400 * Task that sends FIND PEER requests.
402 static GNUNET_SCHEDULER_TaskIdentifier find_peer_task;
405 * Identity of this peer.
407 static struct GNUNET_PeerIdentity my_identity;
410 * Handle to GNUnet core.
412 static struct GNUNET_CORE_Handle *coreAPI;
416 * Find the optimal bucket for this key.
418 * @param hc the hashcode to compare our identity to
419 * @return the proper bucket index, or GNUNET_SYSERR
420 * on error (same hashcode)
423 find_bucket (const GNUNET_HashCode * hc)
427 bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, hc);
428 if (bits == MAX_BUCKETS)
430 /* How can all bits match? Got my own ID? */
432 return GNUNET_SYSERR;
434 return MAX_BUCKETS - bits - 1;
439 * Let GNUnet core know that we like the given peer.
441 * @param cls the 'struct PeerInfo' of the peer
442 * @param tc scheduler context.
445 update_core_preference (void *cls,
446 const struct GNUNET_SCHEDULER_TaskContext *tc);
450 * Function called with statistics about the given peer.
453 * @param peer identifies the peer
454 * @param bpm_out set to the current bandwidth limit (sending) for this peer
455 * @param amount set to the amount that was actually reserved or unreserved;
456 * either the full requested amount or zero (no partial reservations)
457 * @param res_delay if the reservation could not be satisfied (amount was 0), how
458 * long should the client wait until re-trying?
459 * @param preference current traffic preference for the given peer
462 update_core_preference_finish (void *cls,
463 const struct GNUNET_PeerIdentity *peer,
464 struct GNUNET_BANDWIDTH_Value32NBO bpm_out,
466 struct GNUNET_TIME_Relative res_delay,
469 struct PeerInfo *peer_info = cls;
471 peer_info->info_ctx = NULL;
472 peer_info->preference_task
473 = GNUNET_SCHEDULER_add_delayed (DHT_DEFAULT_PREFERENCE_INTERVAL,
474 &update_core_preference, peer_info);
479 * Let GNUnet core know that we like the given peer.
481 * @param cls the 'struct PeerInfo' of the peer
482 * @param tc scheduler context.
485 update_core_preference (void *cls,
486 const struct GNUNET_SCHEDULER_TaskContext *tc)
488 struct PeerInfo *peer = cls;
490 unsigned int matching;
493 peer->preference_task = GNUNET_SCHEDULER_NO_TASK;
494 if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
497 GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey,
498 &peer->id.hashPubKey);
501 bucket = find_bucket (&peer->id.hashPubKey);
502 if (bucket == GNUNET_SYSERR)
505 preference = (1LL << matching) / k_buckets[bucket].peers_size;
508 peer->preference_task
509 = GNUNET_SCHEDULER_add_delayed (DHT_DEFAULT_PREFERENCE_INTERVAL,
510 &update_core_preference, peer);
513 GNUNET_STATISTICS_update (GDS_stats,
514 gettext_noop ("# Preference updates given to core"), 1,
517 GNUNET_CORE_peer_change_preference (coreAPI, &peer->id,
518 GNUNET_TIME_UNIT_FOREVER_REL,
519 GNUNET_BANDWIDTH_VALUE_MAX, 0,
521 &update_core_preference_finish, peer);
526 * Closure for 'add_known_to_bloom'.
528 struct BloomConstructorContext
531 * Bloom filter under construction.
533 struct GNUNET_CONTAINER_BloomFilter *bloom;
543 * Add each of the peers we already know to the bloom filter of
544 * the request so that we don't get duplicate HELLOs.
546 * @param cls the 'struct BloomConstructorContext'.
547 * @param key peer identity to add to the bloom filter
548 * @param value value the peer information (unused)
549 * @return GNUNET_YES (we should continue to iterate)
552 add_known_to_bloom (void *cls, const GNUNET_HashCode * key, void *value)
554 struct BloomConstructorContext *ctx = cls;
557 GNUNET_BLOCK_mingle_hash (key, ctx->bf_mutator, &mh);
558 GNUNET_CONTAINER_bloomfilter_add (ctx->bloom, &mh);
564 * Task to send a find peer message for our own peer identifier
565 * so that we can find the closest peers in the network to ourselves
566 * and attempt to connect to them.
568 * @param cls closure for this task
569 * @param tc the context under which the task is running
572 send_find_peer_message (void *cls,
573 const struct GNUNET_SCHEDULER_TaskContext *tc)
575 struct GNUNET_TIME_Relative next_send_time;
576 struct BloomConstructorContext bcc;
577 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
579 find_peer_task = GNUNET_SCHEDULER_NO_TASK;
580 if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
582 if (newly_found_peers > bucket_size)
584 /* If we are finding many peers already, no need to send out our request right now! */
585 find_peer_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES,
586 &send_find_peer_message, NULL);
587 newly_found_peers = 0;
590 bcc.bf_mutator = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, UINT32_MAX);
592 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, GNUNET_CONSTANTS_BLOOMFILTER_K);
593 GNUNET_CONTAINER_multihashmap_iterate (all_known_peers,
596 GNUNET_STATISTICS_update (GDS_stats,
597 gettext_noop ("# FIND PEER messages initiated"), 1,
599 peer_bf = GNUNET_CONTAINER_bloomfilter_init (NULL,
601 GNUNET_CONSTANTS_BLOOMFILTER_K);
602 // FIXME: pass priority!?
603 GDS_NEIGHBOURS_handle_get (GNUNET_BLOCK_TYPE_DHT_HELLO,
604 GNUNET_DHT_RO_FIND_PEER,
605 FIND_PEER_REPLICATION_LEVEL,
607 &my_identity.hashPubKey,
609 bcc.bloom, bcc.bf_mutator,
611 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
612 GNUNET_CONTAINER_bloomfilter_free (bcc.bloom);
613 /* schedule next round */
614 newly_found_peers = 0;
615 next_send_time.rel_value =
616 (DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value / 2) +
617 GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_STRONG,
618 DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value / 2);
619 find_peer_task = GNUNET_SCHEDULER_add_delayed (next_send_time,
620 &send_find_peer_message,
626 * Method called whenever a peer connects.
629 * @param peer peer identity this notification is about
630 * @param atsi performance data
633 handle_core_connect (void *cls, const struct GNUNET_PeerIdentity *peer,
634 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
636 struct PeerInfo *ret;
639 /* Check for connect to self message */
640 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
643 GNUNET_CONTAINER_multihashmap_contains (all_known_peers,
649 GNUNET_STATISTICS_update (GDS_stats,
650 gettext_noop ("# Peers connected"), 1,
652 peer_bucket = find_bucket (&peer->hashPubKey);
653 GNUNET_assert ( (peer_bucket >= 0) && (peer_bucket < MAX_BUCKETS) );
654 ret = GNUNET_malloc (sizeof (struct PeerInfo));
656 ret->latency = latency;
657 ret->distance = distance;
660 GNUNET_CONTAINER_DLL_insert_tail (k_buckets[peer_bucket].head,
661 k_buckets[peer_bucket].tail, ret);
662 k_buckets[peer_bucket].peers_size++;
663 closest_bucket = GNUNET_MAX (closest_bucket,
665 if ( (peer_bucket > 0) &&
666 (k_buckets[peer_bucket].peers_size <= bucket_size) )
667 ret->preference_task = GNUNET_SCHEDULER_add_now (&update_core_preference, ret);
669 GNUNET_assert (GNUNET_OK ==
670 GNUNET_CONTAINER_multihashmap_put (all_known_peers,
671 &peer->hashPubKey, ret,
672 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
673 if (1 == GNUNET_CONTAINER_multihashmap_size (all_known_peers))
675 /* got a first connection, good time to start with FIND PEER requests... */
676 find_peer_task = GNUNET_SCHEDULER_add_now (&send_find_peer_message,
683 * Method called whenever a peer disconnects.
686 * @param peer peer identity this notification is about
689 handle_core_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer)
691 struct PeerInfo *to_remove;
693 struct P2PPendingMessage *pos;
695 /* Check for disconnect from self message */
696 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
699 GNUNET_CONTAINER_multihashmap_get (all_known_peers, &peer->hashPubKey);
700 if (NULL == to_remove)
705 GNUNET_STATISTICS_update (GDS_stats,
706 gettext_noop ("# Peers connected"), -1,
708 GNUNET_assert (GNUNET_YES ==
709 GNUNET_CONTAINER_multihashmap_remove (all_known_peers,
712 if (NULL != to_remove->info_ctx)
714 GNUNET_CORE_peer_change_preference_cancel (to_remove->info_ctx);
715 to_remove->info_ctx = NULL;
717 if (GNUNET_SCHEDULER_NO_TASK != to_remove->preference_task)
719 GNUNET_SCHEDULER_cancel (to_remove->preference_task);
720 to_remove->preference_task = GNUNET_SCHEDULER_NO_TASK;
722 current_bucket = find_bucket (&to_remove->id.hashPubKey);
723 GNUNET_CONTAINER_DLL_remove (k_buckets[current_bucket].head,
724 k_buckets[current_bucket].tail,
726 GNUNET_assert (k_buckets[current_bucket].peers_size > 0);
727 k_buckets[current_bucket].peers_size--;
728 while ( (closest_bucket > 0) &&
729 (k_buckets[closest_bucket].peers_size == 0) )
732 if (to_remove->th != NULL)
734 GNUNET_CORE_notify_transmit_ready_cancel (to_remove->th);
735 to_remove->th = NULL;
737 while (NULL != (pos = to_remove->head))
739 GNUNET_CONTAINER_DLL_remove (to_remove->head,
748 * Called when core is ready to send a message we asked for
749 * out to the destination.
751 * @param cls the 'struct PeerInfo' of the target peer
752 * @param size number of bytes available in buf
753 * @param buf where the callee should write the message
754 * @return number of bytes written to buf
757 core_transmit_notify (void *cls, size_t size, void *buf)
759 struct PeerInfo *peer = cls;
761 struct P2PPendingMessage *pending;
768 /* client disconnected */
771 if (peer->head == NULL)
773 /* no messages pending */
777 while ( (NULL != (pending = peer->head)) &&
778 (size - off >= (msize = ntohs (pending->msg->size))) )
780 GNUNET_STATISTICS_update (GDS_stats,
781 gettext_noop ("# Bytes transmitted to other peers"), msize,
783 memcpy (&cbuf[off], pending->msg, msize);
785 peer->pending_count--;
786 GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, pending);
787 GNUNET_free (pending);
789 if (peer->head != NULL)
792 = GNUNET_CORE_notify_transmit_ready (coreAPI, GNUNET_YES,
794 GNUNET_TIME_absolute_get_remaining (pending->timeout),
796 &core_transmit_notify, peer);
803 * Transmit all messages in the peer's message queue.
805 * @param peer message queue to process
808 process_peer_queue (struct PeerInfo *peer)
810 struct P2PPendingMessage *pending;
812 if (NULL == (pending = peer->head))
814 if (NULL != peer->th)
816 GNUNET_STATISTICS_update (GDS_stats,
817 gettext_noop ("# Bytes of bandwdith requested from core"),
818 ntohs (pending->msg->size),
821 = GNUNET_CORE_notify_transmit_ready (coreAPI, GNUNET_YES,
823 GNUNET_TIME_absolute_get_remaining (pending->timeout),
825 ntohs (pending->msg->size),
826 &core_transmit_notify, peer);
831 * To how many peers should we (on average) forward the request to
832 * obtain the desired target_replication count (on average).
834 * @param hop_count number of hops the message has traversed
835 * @param target_replication the number of total paths desired
836 * @return Some number of peers to forward the message to
839 get_forward_count (uint32_t hop_count,
840 uint32_t target_replication)
842 uint32_t random_value;
843 uint32_t forward_count;
846 if (hop_count > GDS_NSE_get () * 4.0)
848 /* forcefully terminate */
851 if (hop_count > GDS_NSE_get () * 2.0)
853 /* Once we have reached our ideal number of hops, only forward to 1 peer */
856 /* bound by system-wide maximum */
857 target_replication = GNUNET_MIN (MAXIMUM_REPLICATION_LEVEL,
860 1 + (target_replication - 1.0) / (GDS_NSE_get () +
861 ((float) (target_replication - 1.0) *
863 /* Set forward count to floor of target_value */
864 forward_count = (uint32_t) target_value;
865 /* Subtract forward_count (floor) from target_value (yields value between 0 and 1) */
866 target_value = target_value - forward_count;
868 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, UINT32_MAX);
869 if (random_value < (target_value * UINT32_MAX))
871 return forward_count;
876 * Compute the distance between have and target as a 32-bit value.
877 * Differences in the lower bits must count stronger than differences
878 * in the higher bits.
880 * @return 0 if have==target, otherwise a number
881 * that is larger as the distance between
882 * the two hash codes increases
885 get_distance (const GNUNET_HashCode * target, const GNUNET_HashCode * have)
892 /* We have to represent the distance between two 2^9 (=512)-bit
893 * numbers as a 2^5 (=32)-bit number with "0" being used for the
894 * two numbers being identical; furthermore, we need to
895 * guarantee that a difference in the number of matching
896 * bits is always represented in the result.
898 * We use 2^32/2^9 numerical values to distinguish between
899 * hash codes that have the same LSB bit distance and
900 * use the highest 2^9 bits of the result to signify the
901 * number of (mis)matching LSB bits; if we have 0 matching
902 * and hence 512 mismatching LSB bits we return -1 (since
903 * 512 itself cannot be represented with 9 bits) */
905 /* first, calculate the most significant 9 bits of our
906 * result, aka the number of LSBs */
907 bucket = GNUNET_CRYPTO_hash_matching_bits (target, have);
908 /* bucket is now a value between 0 and 512 */
910 return 0; /* perfect match */
912 return (unsigned int) -1; /* LSB differs; use max (if we did the bit-shifting
913 * below, we'd end up with max+1 (overflow)) */
915 /* calculate the most significant bits of the final result */
916 msb = (512 - bucket) << (32 - 9);
917 /* calculate the 32-9 least significant bits of the final result by
918 * looking at the differences in the 32-9 bits following the
919 * mismatching bit at 'bucket' */
922 (i < sizeof (GNUNET_HashCode) * 8) && (i < bucket + 1 + 32 - 9); i++)
924 if (GNUNET_CRYPTO_hash_get_bit (target, i) !=
925 GNUNET_CRYPTO_hash_get_bit (have, i))
926 lsb |= (1 << (bucket + 32 - 9 - i)); /* first bit set will be 10,
927 * last bit set will be 31 -- if
928 * i does not reach 512 first... */
935 * Check whether my identity is closer than any known peers. If a
936 * non-null bloomfilter is given, check if this is the closest peer
937 * that hasn't already been routed to.
939 * @param key hash code to check closeness to
940 * @param bloom bloomfilter, exclude these entries from the decision
941 * @return GNUNET_YES if node location is closest,
942 * GNUNET_NO otherwise.
945 am_closest_peer (const GNUNET_HashCode *key,
946 const struct GNUNET_CONTAINER_BloomFilter *bloom)
952 struct PeerInfo *pos;
954 if (0 == memcmp (&my_identity.hashPubKey, key, sizeof (GNUNET_HashCode)))
956 bucket_num = find_bucket (key);
957 bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, key);
958 pos = k_buckets[bucket_num].head;
960 while ((pos != NULL) && (count < bucket_size))
962 if ((bloom != NULL) &&
964 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)))
967 continue; /* Skip already checked entries */
969 other_bits = GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey, key);
970 if (other_bits > bits)
972 if (other_bits == bits) /* We match the same number of bits */
976 /* No peers closer, we are the closest! */
982 * Select a peer from the routing table that would be a good routing
983 * destination for sending a message for "key". The resulting peer
984 * must not be in the set of blocked peers.<p>
986 * Note that we should not ALWAYS select the closest peer to the
987 * target, peers further away from the target should be chosen with
988 * exponentially declining probability.
990 * FIXME: double-check that this is fine
993 * @param key the key we are selecting a peer to route to
994 * @param bloom a bloomfilter containing entries this request has seen already
995 * @param hops how many hops has this message traversed thus far
996 * @return Peer to route to, or NULL on error
998 static struct PeerInfo *
999 select_peer (const GNUNET_HashCode *key,
1000 const struct GNUNET_CONTAINER_BloomFilter *bloom,
1005 unsigned int selected;
1006 struct PeerInfo *pos;
1008 unsigned int smallest_distance;
1009 struct PeerInfo *chosen;
1011 if (hops >= GDS_NSE_get ())
1013 /* greedy selection (closest peer that is not in bloomfilter) */
1014 smallest_distance = UINT_MAX;
1016 for (bc = closest_bucket; bc < MAX_BUCKETS; bc++)
1018 pos = k_buckets[bc].head;
1020 while ((pos != NULL) && (count < bucket_size))
1023 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey))
1025 dist = get_distance (key, &pos->id.hashPubKey);
1026 if (dist < smallest_distance)
1029 smallest_distance = dist;
1034 GNUNET_STATISTICS_update (GDS_stats,
1035 gettext_noop ("# Peers excluded from routing due to Bloomfilter"), 1,
1043 GNUNET_STATISTICS_update (GDS_stats,
1044 gettext_noop ("# Peer selection failed"), 1,
1049 /* select "random" peer */
1050 /* count number of peers that are available and not filtered */
1052 for (bc = closest_bucket; bc < MAX_BUCKETS; bc++)
1054 pos = k_buckets[bc].head;
1055 while ((pos != NULL) && (count < bucket_size))
1057 if ( (bloom != NULL) &&
1059 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)) )
1061 GNUNET_STATISTICS_update (GDS_stats,
1062 gettext_noop ("# Peers excluded from routing due to Bloomfilter"), 1,
1065 continue; /* Ignore bloomfiltered peers */
1071 if (count == 0) /* No peers to select from! */
1073 GNUNET_STATISTICS_update (GDS_stats,
1074 gettext_noop ("# Peer selection failed"), 1,
1078 /* Now actually choose a peer */
1079 selected = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, count);
1081 for (bc = closest_bucket; bc < MAX_BUCKETS; bc++)
1083 pos = k_buckets[bc].head;
1084 while ((pos != NULL) && (count < bucket_size))
1086 if ( (bloom != NULL) &&
1088 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)) )
1091 continue; /* Ignore bloomfiltered peers */
1093 if (0 == selected--)
1104 * Compute the set of peers that the given request should be
1107 * @param key routing key
1108 * @param bloom bloom filter excluding peers as targets, all selected
1109 * peers will be added to the bloom filter
1110 * @param hop_count number of hops the request has traversed so far
1111 * @param target_replication desired number of replicas
1112 * @param targets where to store an array of target peers (to be
1113 * free'd by the caller)
1114 * @return number of peers returned in 'targets'.
1117 get_target_peers (const GNUNET_HashCode *key,
1118 struct GNUNET_CONTAINER_BloomFilter *bloom,
1120 uint32_t target_replication,
1121 struct PeerInfo ***targets)
1125 struct PeerInfo **rtargets;
1126 struct PeerInfo *nxt;
1128 GNUNET_assert (NULL != bloom);
1129 ret = get_forward_count (hop_count, target_replication);
1135 rtargets = GNUNET_malloc (sizeof (struct PeerInfo*) * ret);
1139 nxt = select_peer (key, bloom, hop_count);
1142 rtargets[off++] = nxt;
1143 GNUNET_break (GNUNET_NO ==
1144 GNUNET_CONTAINER_bloomfilter_test (bloom, &nxt->id.hashPubKey));
1145 GNUNET_CONTAINER_bloomfilter_add (bloom, &nxt->id.hashPubKey);
1149 GNUNET_free (rtargets);
1153 *targets = rtargets;
1159 * Perform a PUT operation. Forwards the given request to other
1160 * peers. Does not store the data locally. Does not give the
1161 * data to local clients. May do nothing if this is the only
1162 * peer in the network (or if we are the closest peer in the
1165 * @param type type of the block
1166 * @param options routing options
1167 * @param desired_replication_level desired replication count
1168 * @param expiration_time when does the content expire
1169 * @param hop_count how many hops has this message traversed so far
1170 * @param bf Bloom filter of peers this PUT has already traversed
1171 * @param key key for the content
1172 * @param put_path_length number of entries in put_path
1173 * @param put_path peers this request has traversed so far (if tracked)
1174 * @param data payload to store
1175 * @param data_size number of bytes in data
1178 GDS_NEIGHBOURS_handle_put (enum GNUNET_BLOCK_Type type,
1179 enum GNUNET_DHT_RouteOption options,
1180 uint32_t desired_replication_level,
1181 struct GNUNET_TIME_Absolute expiration_time,
1183 struct GNUNET_CONTAINER_BloomFilter *bf,
1184 const GNUNET_HashCode *key,
1185 unsigned int put_path_length,
1186 struct GNUNET_PeerIdentity *put_path,
1190 unsigned int target_count;
1192 struct PeerInfo **targets;
1193 struct PeerInfo *target;
1194 struct P2PPendingMessage *pending;
1196 struct PeerPutMessage *ppm;
1197 struct GNUNET_PeerIdentity *pp;
1199 GNUNET_assert (NULL != bf);
1200 GNUNET_CONTAINER_bloomfilter_add (bf, &my_identity.hashPubKey);
1201 GNUNET_STATISTICS_update (GDS_stats,
1202 gettext_noop ("# PUT requests routed"), 1,
1204 target_count = get_target_peers (key, bf, hop_count,
1205 desired_replication_level,
1207 if (0 == target_count)
1209 msize = put_path_length * sizeof (struct GNUNET_PeerIdentity) + data_size + sizeof (struct PeerPutMessage);
1210 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1212 put_path_length = 0;
1213 msize = data_size + sizeof (struct PeerPutMessage);
1215 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1220 GNUNET_STATISTICS_update (GDS_stats,
1221 gettext_noop ("# Peers selected as targets for PUT requests"), target_count,
1223 for (i=0;i<target_count;i++)
1225 target = targets[i];
1226 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1227 pending->importance = 0; /* FIXME */
1228 pending->timeout = expiration_time;
1229 ppm = (struct PeerPutMessage*) &pending[1];
1230 pending->msg = &ppm->header;
1231 ppm->header.size = htons (msize);
1232 ppm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_PUT);
1233 ppm->options = htonl (options);
1234 ppm->type = htonl (type);
1235 ppm->hop_count = htonl (hop_count + 1);
1236 ppm->desired_replication_level = htonl (desired_replication_level);
1237 ppm->put_path_length = htonl (put_path_length);
1238 ppm->expiration_time = GNUNET_TIME_absolute_hton (expiration_time);
1239 GNUNET_break (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bf, &target->id.hashPubKey));
1240 GNUNET_assert (GNUNET_OK ==
1241 GNUNET_CONTAINER_bloomfilter_get_raw_data (bf,
1245 pp = (struct GNUNET_PeerIdentity*) &ppm[1];
1246 memcpy (pp, put_path, sizeof (struct GNUNET_PeerIdentity) * put_path_length);
1247 memcpy (&pp[put_path_length], data, data_size);
1248 GNUNET_CONTAINER_DLL_insert_tail (target->head,
1251 target->pending_count++;
1252 process_peer_queue (target);
1254 GNUNET_free (targets);
1259 * Perform a GET operation. Forwards the given request to other
1260 * peers. Does not lookup the key locally. May do nothing if this is
1261 * the only peer in the network (or if we are the closest peer in the
1264 * @param type type of the block
1265 * @param options routing options
1266 * @param desired_replication_level desired replication count
1267 * @param hop_count how many hops did this request traverse so far?
1268 * @param key key for the content
1269 * @param xquery extended query
1270 * @param xquery_size number of bytes in xquery
1271 * @param reply_bf bloomfilter to filter duplicates
1272 * @param reply_bf_mutator mutator for reply_bf
1273 * @param peer_bf filter for peers not to select (again)
1276 GDS_NEIGHBOURS_handle_get (enum GNUNET_BLOCK_Type type,
1277 enum GNUNET_DHT_RouteOption options,
1278 uint32_t desired_replication_level,
1280 const GNUNET_HashCode *key,
1283 const struct GNUNET_CONTAINER_BloomFilter *reply_bf,
1284 uint32_t reply_bf_mutator,
1285 struct GNUNET_CONTAINER_BloomFilter *peer_bf)
1287 unsigned int target_count;
1289 struct PeerInfo **targets;
1290 struct PeerInfo *target;
1291 struct P2PPendingMessage *pending;
1293 struct PeerGetMessage *pgm;
1295 size_t reply_bf_size;
1297 GNUNET_assert (NULL != peer_bf);
1298 GNUNET_CONTAINER_bloomfilter_add (peer_bf, &my_identity.hashPubKey);
1299 GNUNET_STATISTICS_update (GDS_stats,
1300 gettext_noop ("# GET requests routed"), 1,
1302 target_count = get_target_peers (key, peer_bf, hop_count,
1303 desired_replication_level,
1305 if (0 == target_count)
1307 reply_bf_size = GNUNET_CONTAINER_bloomfilter_get_size (reply_bf);
1308 msize = xquery_size + sizeof (struct PeerGetMessage) + reply_bf_size;
1309 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1314 GNUNET_STATISTICS_update (GDS_stats,
1315 gettext_noop ("# Peers selected as targets for GET requests"), target_count,
1317 /* forward request */
1318 for (i=0;i<target_count;i++)
1320 target = targets[i];
1321 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1322 pending->importance = 0; /* FIXME */
1323 pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
1324 pgm = (struct PeerGetMessage*) &pending[1];
1325 pending->msg = &pgm->header;
1326 pgm->header.size = htons (msize);
1327 pgm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_GET);
1328 pgm->options = htonl (options);
1329 pgm->type = htonl (type);
1330 pgm->hop_count = htonl (hop_count + 1);
1331 pgm->desired_replication_level = htonl (desired_replication_level);
1332 pgm->xquery_size = htonl (xquery_size);
1333 pgm->bf_mutator = reply_bf_mutator;
1334 GNUNET_break (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (peer_bf, &target->id.hashPubKey));
1335 GNUNET_assert (GNUNET_OK ==
1336 GNUNET_CONTAINER_bloomfilter_get_raw_data (peer_bf,
1340 xq = (char *) &pgm[1];
1341 memcpy (xq, xquery, xquery_size);
1342 if (NULL != reply_bf)
1343 GNUNET_assert (GNUNET_OK ==
1344 GNUNET_CONTAINER_bloomfilter_get_raw_data (reply_bf,
1347 GNUNET_CONTAINER_DLL_insert_tail (target->head,
1350 target->pending_count++;
1351 process_peer_queue (target);
1353 GNUNET_free (targets);
1358 * Handle a reply (route to origin). Only forwards the reply back to
1359 * the given peer. Does not do local caching or forwarding to local
1362 * @param target neighbour that should receive the block (if still connected)
1363 * @param type type of the block
1364 * @param expiration_time when does the content expire
1365 * @param key key for the content
1366 * @param put_path_length number of entries in put_path
1367 * @param put_path peers the original PUT traversed (if tracked)
1368 * @param get_path_length number of entries in put_path
1369 * @param get_path peers this reply has traversed so far (if tracked)
1370 * @param data payload of the reply
1371 * @param data_size number of bytes in data
1374 GDS_NEIGHBOURS_handle_reply (const struct GNUNET_PeerIdentity *target,
1375 enum GNUNET_BLOCK_Type type,
1376 struct GNUNET_TIME_Absolute expiration_time,
1377 const GNUNET_HashCode *key,
1378 unsigned int put_path_length,
1379 const struct GNUNET_PeerIdentity *put_path,
1380 unsigned int get_path_length,
1381 const struct GNUNET_PeerIdentity *get_path,
1385 struct PeerInfo *pi;
1386 struct P2PPendingMessage *pending;
1388 struct PeerResultMessage *prm;
1389 struct GNUNET_PeerIdentity *paths;
1391 msize = data_size + sizeof (struct PeerResultMessage) +
1392 (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity);
1393 if ( (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE) ||
1394 (get_path_length > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
1395 (put_path_length > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
1396 (data_size > GNUNET_SERVER_MAX_MESSAGE_SIZE) )
1401 pi = GNUNET_CONTAINER_multihashmap_get (all_known_peers,
1402 &target->hashPubKey);
1405 /* peer disconnected in the meantime, drop reply */
1408 GNUNET_STATISTICS_update (GDS_stats,
1409 gettext_noop ("# REPLIES routed"), 1,
1411 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1412 pending->importance = 0; /* FIXME */
1413 pending->timeout = expiration_time;
1414 prm = (struct PeerResultMessage*) &pending[1];
1415 pending->msg = &prm->header;
1416 prm->header.size = htons (msize);
1417 prm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT);
1418 prm->type = htonl (type);
1419 prm->put_path_length = htonl (put_path_length);
1420 prm->get_path_length = htonl (get_path_length);
1421 prm->expiration_time = GNUNET_TIME_absolute_hton (expiration_time);
1423 paths = (struct GNUNET_PeerIdentity*) &prm[1];
1424 memcpy (paths, put_path, put_path_length * sizeof (struct GNUNET_PeerIdentity));
1425 memcpy (&paths[put_path_length],
1426 get_path, get_path_length * sizeof (struct GNUNET_PeerIdentity));
1427 memcpy (&paths[put_path_length + get_path_length],
1429 GNUNET_CONTAINER_DLL_insert (pi->head,
1432 pi->pending_count++;
1433 process_peer_queue (pi);
1438 * To be called on core init/fail.
1440 * @param cls service closure
1441 * @param server handle to the server for this service
1442 * @param identity the public identity of this peer
1443 * @param publicKey the public key of this peer
1446 core_init (void *cls, struct GNUNET_CORE_Handle *server,
1447 const struct GNUNET_PeerIdentity *identity,
1448 const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *publicKey)
1450 GNUNET_assert (server != NULL);
1451 my_identity = *identity;
1456 * Core handler for p2p put requests.
1458 * @param cls closure
1459 * @param peer sender of the request
1460 * @param message message
1461 * @param peer peer identity this notification is about
1462 * @param atsi performance data
1463 * @return GNUNET_OK to keep the connection open,
1464 * GNUNET_SYSERR to close it (signal serious error)
1467 handle_dht_p2p_put (void *cls,
1468 const struct GNUNET_PeerIdentity *peer,
1469 const struct GNUNET_MessageHeader *message,
1470 const struct GNUNET_TRANSPORT_ATS_Information
1473 const struct PeerPutMessage *put;
1474 const struct GNUNET_PeerIdentity *put_path;
1475 const void *payload;
1478 size_t payload_size;
1479 enum GNUNET_DHT_RouteOption options;
1480 struct GNUNET_CONTAINER_BloomFilter *bf;
1481 GNUNET_HashCode test_key;
1483 msize = ntohs (message->size);
1484 if (msize < sizeof (struct PeerPutMessage))
1486 GNUNET_break_op (0);
1489 put = (const struct PeerPutMessage*) message;
1490 putlen = ntohl (put->put_path_length);
1491 if ( (msize < sizeof (struct PeerPutMessage) + putlen * sizeof (struct GNUNET_PeerIdentity)) ||
1492 (putlen > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) )
1494 GNUNET_break_op (0);
1497 GNUNET_STATISTICS_update (GDS_stats,
1498 gettext_noop ("# P2P PUT requests received"), 1,
1500 put_path = (const struct GNUNET_PeerIdentity*) &put[1];
1501 payload = &put_path[putlen];
1502 options = ntohl (put->options);
1503 payload_size = msize - (sizeof (struct PeerPutMessage) +
1504 putlen * sizeof (struct GNUNET_PeerIdentity));
1505 switch (GNUNET_BLOCK_get_key (GDS_block_context,
1507 payload, payload_size,
1511 if (0 != memcmp (&test_key, &put->key, sizeof (GNUNET_HashCode)))
1513 GNUNET_break_op (0);
1518 GNUNET_break_op (0);
1521 /* cannot verify, good luck */
1524 bf = GNUNET_CONTAINER_bloomfilter_init (put->bloomfilter,
1526 GNUNET_CONSTANTS_BLOOMFILTER_K);
1527 GNUNET_break_op (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bf, &peer->hashPubKey));
1529 struct GNUNET_PeerIdentity pp[putlen+1];
1531 /* extend 'put path' by sender */
1532 if (0 != (options & GNUNET_DHT_RO_RECORD_ROUTE))
1534 memcpy (pp, put_path, putlen * sizeof (struct GNUNET_PeerIdentity));
1541 /* give to local clients */
1542 GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (put->expiration_time),
1551 if ( (0 != (options & GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE)) ||
1552 (am_closest_peer (&put->key,
1554 GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (put->expiration_time),
1560 /* route to other peers */
1561 GDS_NEIGHBOURS_handle_put (ntohl (put->type),
1563 ntohl (put->desired_replication_level),
1564 GNUNET_TIME_absolute_ntoh (put->expiration_time),
1565 ntohl (put->hop_count) + 1 /* who adds +1? */,
1572 GNUNET_CONTAINER_bloomfilter_free (bf);
1578 * We have received a FIND PEER request. Send matching
1581 * @param sender sender of the FIND PEER request
1582 * @param key peers close to this key are desired
1583 * @param bf peers matching this bf are excluded
1584 * @param bf_mutator mutator for bf
1587 handle_find_peer (const struct GNUNET_PeerIdentity *sender,
1588 const GNUNET_HashCode *key,
1589 struct GNUNET_CONTAINER_BloomFilter *bf,
1590 uint32_t bf_mutator)
1593 struct PeerBucket *bucket;
1594 struct PeerInfo *peer;
1595 unsigned int choice;
1596 GNUNET_HashCode mhash;
1597 const struct GNUNET_HELLO_Message *hello;
1599 /* first, check about our own HELLO */
1600 if (NULL != GDS_my_hello)
1602 GNUNET_BLOCK_mingle_hash (&my_identity.hashPubKey, bf_mutator, &mhash);
1603 if ( (NULL == bf) ||
1604 (GNUNET_YES != GNUNET_CONTAINER_bloomfilter_test (bf, &mhash)) )
1606 GDS_NEIGHBOURS_handle_reply (sender,
1607 GNUNET_BLOCK_TYPE_DHT_HELLO,
1608 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_HELLO_ADDRESS_EXPIRATION),
1613 GNUNET_HELLO_size ((const struct GNUNET_HELLO_Message*) GDS_my_hello));
1617 GNUNET_STATISTICS_update (GDS_stats,
1618 gettext_noop ("# FIND PEER requests ignored due to Bloomfilter"), 1,
1624 GNUNET_STATISTICS_update (GDS_stats,
1625 gettext_noop ("# FIND PEER requests ignored due to lack of HELLO"), 1,
1629 /* then, also consider sending a random HELLO from the closest bucket */
1630 if (0 == memcmp (&my_identity.hashPubKey, key, sizeof (GNUNET_HashCode)))
1631 bucket_idx = closest_bucket;
1633 bucket_idx = GNUNET_MIN (closest_bucket, find_bucket (key));
1634 if (bucket_idx == GNUNET_SYSERR)
1636 bucket = &k_buckets[bucket_idx];
1637 if (bucket->peers_size == 0)
1639 choice = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1640 bucket->peers_size);
1641 peer = bucket->head;
1644 GNUNET_assert (peer != NULL);
1647 choice = bucket->peers_size;
1652 return; /* no non-masked peer available */
1654 peer = bucket->head;
1655 GNUNET_BLOCK_mingle_hash (&peer->id.hashPubKey, bf_mutator, &mhash);
1656 hello = GDS_HELLO_get (&peer->id);
1658 while ( (hello == NULL) ||
1659 (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bf, &mhash)) );
1660 GDS_NEIGHBOURS_handle_reply (sender,
1661 GNUNET_BLOCK_TYPE_DHT_HELLO,
1662 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_HELLO_ADDRESS_EXPIRATION),
1667 GNUNET_HELLO_size (hello));
1672 * Core handler for p2p get requests.
1674 * @param cls closure
1675 * @param peer sender of the request
1676 * @param message message
1677 * @param peer peer identity this notification is about
1678 * @param atsi performance data
1679 * @return GNUNET_OK to keep the connection open,
1680 * GNUNET_SYSERR to close it (signal serious error)
1683 handle_dht_p2p_get (void *cls, const struct GNUNET_PeerIdentity *peer,
1684 const struct GNUNET_MessageHeader *message,
1685 const struct GNUNET_TRANSPORT_ATS_Information
1688 struct PeerGetMessage *get;
1689 uint32_t xquery_size;
1690 size_t reply_bf_size;
1692 enum GNUNET_BLOCK_Type type;
1693 enum GNUNET_DHT_RouteOption options;
1694 enum GNUNET_BLOCK_EvaluationResult eval;
1695 struct GNUNET_CONTAINER_BloomFilter *reply_bf;
1696 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
1699 GNUNET_break (0 != memcmp (peer, &my_identity, sizeof (struct GNUNET_PeerIdentity)));
1700 /* parse and validate message */
1701 msize = ntohs (message->size);
1702 if (msize < sizeof (struct PeerGetMessage))
1704 GNUNET_break_op (0);
1707 get = (struct PeerGetMessage *) message;
1708 xquery_size = ntohl (get->xquery_size);
1709 if (msize < sizeof (struct PeerGetMessage) + xquery_size)
1711 GNUNET_break_op (0);
1714 GNUNET_STATISTICS_update (GDS_stats,
1715 gettext_noop ("# P2P GET requests received"), 1,
1717 reply_bf_size = msize - (sizeof (struct PeerGetMessage) + xquery_size);
1718 type = ntohl (get->type);
1719 options = ntohl (get->options);
1720 xquery = (const char*) &get[1];
1722 if (reply_bf_size > 0)
1723 reply_bf = GNUNET_CONTAINER_bloomfilter_init (&xquery[xquery_size],
1725 GNUNET_CONSTANTS_BLOOMFILTER_K);
1726 eval = GNUNET_BLOCK_evaluate (GDS_block_context,
1731 xquery, xquery_size,
1733 if (eval != GNUNET_BLOCK_EVALUATION_REQUEST_VALID)
1735 /* request invalid or block type not supported */
1736 GNUNET_break_op (eval == GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED);
1737 if (NULL != reply_bf)
1738 GNUNET_CONTAINER_bloomfilter_free (reply_bf);
1742 GNUNET_CONTAINER_bloomfilter_init (get->bloomfilter,
1744 GNUNET_CONSTANTS_BLOOMFILTER_K);
1745 GNUNET_break_op (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (peer_bf, &peer->hashPubKey));
1746 /* remember request for routing replies */
1747 GDS_ROUTING_add (peer,
1751 xquery, xquery_size,
1752 reply_bf, get->bf_mutator);
1754 /* local lookup (this may update the reply_bf) */
1755 if ( (0 != (options & GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE)) ||
1756 (am_closest_peer (&get->key,
1759 if ( (0 != (options & GNUNET_DHT_RO_FIND_PEER)))
1761 GNUNET_STATISTICS_update (GDS_stats,
1762 gettext_noop ("# P2P FIND PEER requests processed"), 1,
1764 handle_find_peer (peer,
1771 eval = GDS_DATACACHE_handle_get (&get->key,
1773 xquery, xquery_size,
1780 GNUNET_STATISTICS_update (GDS_stats,
1781 gettext_noop ("# P2P GET requests ONLY routed"), 1,
1785 /* P2P forwarding */
1786 if (eval != GNUNET_BLOCK_EVALUATION_OK_LAST)
1787 GDS_NEIGHBOURS_handle_get (type,
1789 ntohl (get->desired_replication_level),
1790 ntohl (get->hop_count) + 1, /* CHECK: where (else) do we do +1? */
1792 xquery, xquery_size,
1797 if (NULL != reply_bf)
1798 GNUNET_CONTAINER_bloomfilter_free (reply_bf);
1799 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
1805 * Core handler for p2p result messages.
1807 * @param cls closure
1808 * @param message message
1809 * @param peer peer identity this notification is about
1810 * @param atsi performance data
1811 * @return GNUNET_YES (do not cut p2p connection)
1814 handle_dht_p2p_result (void *cls, const struct GNUNET_PeerIdentity *peer,
1815 const struct GNUNET_MessageHeader *message,
1816 const struct GNUNET_TRANSPORT_ATS_Information
1819 const struct PeerResultMessage *prm;
1820 const struct GNUNET_PeerIdentity *put_path;
1821 const struct GNUNET_PeerIdentity *get_path;
1823 uint32_t get_path_length;
1824 uint32_t put_path_length;
1827 enum GNUNET_BLOCK_Type type;
1829 /* parse and validate message */
1830 msize = ntohs (message->size);
1831 if (msize < sizeof (struct PeerResultMessage))
1833 GNUNET_break_op (0);
1836 prm = (struct PeerResultMessage *) message;
1837 put_path_length = ntohl (prm->put_path_length);
1838 get_path_length = ntohl (prm->get_path_length);
1839 if ( (msize < sizeof (struct PeerResultMessage) +
1840 (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity)) ||
1841 (get_path_length > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
1842 (put_path_length > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) )
1844 GNUNET_break_op (0);
1847 GNUNET_STATISTICS_update (GDS_stats,
1848 gettext_noop ("# P2P RESULTS received"), 1,
1850 put_path = (const struct GNUNET_PeerIdentity*) &prm[1];
1851 get_path = &put_path[put_path_length];
1852 type = ntohl (prm->type);
1853 data = (const void*) &get_path[get_path_length];
1854 data_size = msize - (sizeof (struct PeerResultMessage) +
1855 (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity));
1857 /* if we got a HELLO, consider it for our own routing table */
1858 if (type == GNUNET_BLOCK_TYPE_DHT_HELLO)
1860 const struct GNUNET_MessageHeader *h;
1861 struct GNUNET_PeerIdentity pid;
1864 /* Should be a HELLO, validate and consider using it! */
1865 if (data_size < sizeof (struct GNUNET_MessageHeader))
1867 GNUNET_break_op (0);
1871 if (data_size != ntohs (h->size))
1873 GNUNET_break_op (0);
1877 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message*) h,
1880 GNUNET_break_op (0);
1883 if (0 != memcmp (&my_identity, &pid, sizeof (struct GNUNET_PeerIdentity)))
1885 bucket = find_bucket (&pid.hashPubKey);
1886 if ( (bucket >= 0) &&
1887 (k_buckets[bucket].peers_size < bucket_size) )
1889 if (NULL != GDS_transport_handle)
1890 GNUNET_TRANSPORT_offer_hello (GDS_transport_handle,
1892 (void) GNUNET_CORE_peer_request_connect (coreAPI,
1899 /* append 'peer' to 'get_path' */
1901 struct GNUNET_PeerIdentity xget_path[get_path_length+1];
1903 memcpy (xget_path, get_path, get_path_length * sizeof (struct GNUNET_PeerIdentity));
1904 xget_path[get_path_length] = *peer;
1907 /* forward to local clients */
1908 GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (prm->expiration_time),
1918 /* forward to other peers */
1919 GDS_ROUTING_process (type,
1920 GNUNET_TIME_absolute_ntoh (prm->expiration_time),
1934 * Initialize neighbours subsystem.
1936 * @return GNUNET_OK on success, GNUNET_SYSERR on error
1939 GDS_NEIGHBOURS_init ()
1941 static struct GNUNET_CORE_MessageHandler core_handlers[] = {
1942 {&handle_dht_p2p_get, GNUNET_MESSAGE_TYPE_DHT_P2P_GET, 0},
1943 {&handle_dht_p2p_put, GNUNET_MESSAGE_TYPE_DHT_P2P_PUT, 0},
1944 {&handle_dht_p2p_result, GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT, 0},
1947 unsigned long long temp_config_num;
1950 GNUNET_CONFIGURATION_get_value_number (GDS_cfg, "DHT", "bucket_size",
1952 bucket_size = (unsigned int) temp_config_num;
1953 coreAPI = GNUNET_CORE_connect (GDS_cfg,
1957 &handle_core_connect,
1958 &handle_core_disconnect,
1959 NULL, /* Do we care about "status" updates? */
1963 if (coreAPI == NULL)
1964 return GNUNET_SYSERR;
1965 all_known_peers = GNUNET_CONTAINER_multihashmap_create (256);
1971 * Shutdown neighbours subsystem.
1974 GDS_NEIGHBOURS_done ()
1976 if (coreAPI == NULL)
1978 GNUNET_CORE_disconnect (coreAPI);
1980 GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (all_known_peers));
1981 GNUNET_CONTAINER_multihashmap_destroy (all_known_peers);
1982 all_known_peers = NULL;
1983 if (GNUNET_SCHEDULER_NO_TASK != find_peer_task)
1985 GNUNET_SCHEDULER_cancel (find_peer_task);
1986 find_peer_task = GNUNET_SCHEDULER_NO_TASK;
1991 /* end of gnunet-service-dht_neighbours.c */