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
16 along with GNUnet; see the file COPYING. If not, write to the
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 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
696 "Peer `%s' disconnected!\n",
698 /* Check for disconnect from self message */
699 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
702 GNUNET_CONTAINER_multihashmap_get (all_known_peers, &peer->hashPubKey);
703 if (NULL == to_remove)
708 GNUNET_STATISTICS_update (GDS_stats,
709 gettext_noop ("# Peers connected"), -1,
711 GNUNET_assert (GNUNET_YES ==
712 GNUNET_CONTAINER_multihashmap_remove (all_known_peers,
715 if (NULL != to_remove->info_ctx)
717 GNUNET_CORE_peer_change_preference_cancel (to_remove->info_ctx);
718 to_remove->info_ctx = NULL;
720 if (GNUNET_SCHEDULER_NO_TASK != to_remove->preference_task)
722 GNUNET_SCHEDULER_cancel (to_remove->preference_task);
723 to_remove->preference_task = GNUNET_SCHEDULER_NO_TASK;
725 current_bucket = find_bucket (&to_remove->id.hashPubKey);
726 GNUNET_CONTAINER_DLL_remove (k_buckets[current_bucket].head,
727 k_buckets[current_bucket].tail,
729 GNUNET_assert (k_buckets[current_bucket].peers_size > 0);
730 k_buckets[current_bucket].peers_size--;
731 while ( (closest_bucket > 0) &&
732 (k_buckets[closest_bucket].peers_size == 0) )
735 if (to_remove->th != NULL)
737 GNUNET_CORE_notify_transmit_ready_cancel (to_remove->th);
738 to_remove->th = NULL;
740 while (NULL != (pos = to_remove->head))
742 GNUNET_CONTAINER_DLL_remove (to_remove->head,
751 * Called when core is ready to send a message we asked for
752 * out to the destination.
754 * @param cls the 'struct PeerInfo' of the target peer
755 * @param size number of bytes available in buf
756 * @param buf where the callee should write the message
757 * @return number of bytes written to buf
760 core_transmit_notify (void *cls, size_t size, void *buf)
762 struct PeerInfo *peer = cls;
764 struct P2PPendingMessage *pending;
771 /* client disconnected */
774 if (peer->head == NULL)
776 /* no messages pending */
780 while ( (NULL != (pending = peer->head)) &&
781 (size - off >= (msize = ntohs (pending->msg->size))) )
783 GNUNET_STATISTICS_update (GDS_stats,
784 gettext_noop ("# Bytes transmitted to other peers"), msize,
786 memcpy (&cbuf[off], pending->msg, msize);
788 peer->pending_count--;
789 GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, pending);
790 GNUNET_free (pending);
792 if (peer->head != NULL)
795 = GNUNET_CORE_notify_transmit_ready (coreAPI, GNUNET_YES,
797 GNUNET_TIME_absolute_get_remaining (pending->timeout),
799 &core_transmit_notify, peer);
806 * Transmit all messages in the peer's message queue.
808 * @param peer message queue to process
811 process_peer_queue (struct PeerInfo *peer)
813 struct P2PPendingMessage *pending;
815 if (NULL == (pending = peer->head))
817 if (NULL != peer->th)
819 GNUNET_STATISTICS_update (GDS_stats,
820 gettext_noop ("# Bytes of bandwdith requested from core"),
821 ntohs (pending->msg->size),
824 = GNUNET_CORE_notify_transmit_ready (coreAPI, GNUNET_YES,
826 GNUNET_TIME_absolute_get_remaining (pending->timeout),
828 ntohs (pending->msg->size),
829 &core_transmit_notify, peer);
834 * To how many peers should we (on average) forward the request to
835 * obtain the desired target_replication count (on average).
837 * @param hop_count number of hops the message has traversed
838 * @param target_replication the number of total paths desired
839 * @return Some number of peers to forward the message to
842 get_forward_count (uint32_t hop_count,
843 uint32_t target_replication)
845 uint32_t random_value;
846 uint32_t forward_count;
849 if (hop_count > GDS_NSE_get () * 4.0)
851 /* forcefully terminate */
854 if (hop_count > GDS_NSE_get () * 2.0)
856 /* Once we have reached our ideal number of hops, only forward to 1 peer */
859 /* bound by system-wide maximum */
860 target_replication = GNUNET_MIN (MAXIMUM_REPLICATION_LEVEL,
863 1 + (target_replication - 1.0) / (GDS_NSE_get () +
864 ((float) (target_replication - 1.0) *
866 /* Set forward count to floor of target_value */
867 forward_count = (uint32_t) target_value;
868 /* Subtract forward_count (floor) from target_value (yields value between 0 and 1) */
869 target_value = target_value - forward_count;
871 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, UINT32_MAX);
872 if (random_value < (target_value * UINT32_MAX))
874 return forward_count;
879 * Compute the distance between have and target as a 32-bit value.
880 * Differences in the lower bits must count stronger than differences
881 * in the higher bits.
883 * @return 0 if have==target, otherwise a number
884 * that is larger as the distance between
885 * the two hash codes increases
888 get_distance (const GNUNET_HashCode * target, const GNUNET_HashCode * have)
895 /* We have to represent the distance between two 2^9 (=512)-bit
896 * numbers as a 2^5 (=32)-bit number with "0" being used for the
897 * two numbers being identical; furthermore, we need to
898 * guarantee that a difference in the number of matching
899 * bits is always represented in the result.
901 * We use 2^32/2^9 numerical values to distinguish between
902 * hash codes that have the same LSB bit distance and
903 * use the highest 2^9 bits of the result to signify the
904 * number of (mis)matching LSB bits; if we have 0 matching
905 * and hence 512 mismatching LSB bits we return -1 (since
906 * 512 itself cannot be represented with 9 bits) */
908 /* first, calculate the most significant 9 bits of our
909 * result, aka the number of LSBs */
910 bucket = GNUNET_CRYPTO_hash_matching_bits (target, have);
911 /* bucket is now a value between 0 and 512 */
913 return 0; /* perfect match */
915 return (unsigned int) -1; /* LSB differs; use max (if we did the bit-shifting
916 * below, we'd end up with max+1 (overflow)) */
918 /* calculate the most significant bits of the final result */
919 msb = (512 - bucket) << (32 - 9);
920 /* calculate the 32-9 least significant bits of the final result by
921 * looking at the differences in the 32-9 bits following the
922 * mismatching bit at 'bucket' */
925 (i < sizeof (GNUNET_HashCode) * 8) && (i < bucket + 1 + 32 - 9); i++)
927 if (GNUNET_CRYPTO_hash_get_bit (target, i) !=
928 GNUNET_CRYPTO_hash_get_bit (have, i))
929 lsb |= (1 << (bucket + 32 - 9 - i)); /* first bit set will be 10,
930 * last bit set will be 31 -- if
931 * i does not reach 512 first... */
938 * Check whether my identity is closer than any known peers. If a
939 * non-null bloomfilter is given, check if this is the closest peer
940 * that hasn't already been routed to.
942 * @param key hash code to check closeness to
943 * @param bloom bloomfilter, exclude these entries from the decision
944 * @return GNUNET_YES if node location is closest,
945 * GNUNET_NO otherwise.
948 am_closest_peer (const GNUNET_HashCode *key,
949 const struct GNUNET_CONTAINER_BloomFilter *bloom)
955 struct PeerInfo *pos;
957 if (0 == memcmp (&my_identity.hashPubKey, key, sizeof (GNUNET_HashCode)))
959 bucket_num = find_bucket (key);
960 bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, key);
961 pos = k_buckets[bucket_num].head;
963 while ((pos != NULL) && (count < bucket_size))
965 if ((bloom != NULL) &&
967 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)))
970 continue; /* Skip already checked entries */
972 other_bits = GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey, key);
973 if (other_bits > bits)
975 if (other_bits == bits) /* We match the same number of bits */
979 /* No peers closer, we are the closest! */
985 * Select a peer from the routing table that would be a good routing
986 * destination for sending a message for "key". The resulting peer
987 * must not be in the set of blocked peers.<p>
989 * Note that we should not ALWAYS select the closest peer to the
990 * target, peers further away from the target should be chosen with
991 * exponentially declining probability.
993 * FIXME: double-check that this is fine
996 * @param key the key we are selecting a peer to route to
997 * @param bloom a bloomfilter containing entries this request has seen already
998 * @param hops how many hops has this message traversed thus far
999 * @return Peer to route to, or NULL on error
1001 static struct PeerInfo *
1002 select_peer (const GNUNET_HashCode *key,
1003 const struct GNUNET_CONTAINER_BloomFilter *bloom,
1008 unsigned int selected;
1009 struct PeerInfo *pos;
1011 unsigned int smallest_distance;
1012 struct PeerInfo *chosen;
1014 if (hops >= GDS_NSE_get ())
1016 /* greedy selection (closest peer that is not in bloomfilter) */
1017 smallest_distance = UINT_MAX;
1019 for (bc = closest_bucket; bc < MAX_BUCKETS; bc++)
1021 pos = k_buckets[bc].head;
1023 while ((pos != NULL) && (count < bucket_size))
1026 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey))
1028 dist = get_distance (key, &pos->id.hashPubKey);
1029 if (dist < smallest_distance)
1032 smallest_distance = dist;
1037 GNUNET_STATISTICS_update (GDS_stats,
1038 gettext_noop ("# Peers excluded from routing due to Bloomfilter"), 1,
1046 GNUNET_STATISTICS_update (GDS_stats,
1047 gettext_noop ("# Peer selection failed"), 1,
1052 /* select "random" peer */
1053 /* count number of peers that are available and not filtered */
1055 for (bc = closest_bucket; bc < MAX_BUCKETS; bc++)
1057 pos = k_buckets[bc].head;
1058 while ((pos != NULL) && (count < bucket_size))
1060 if ( (bloom != NULL) &&
1062 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)) )
1064 GNUNET_STATISTICS_update (GDS_stats,
1065 gettext_noop ("# Peers excluded from routing due to Bloomfilter"), 1,
1068 continue; /* Ignore bloomfiltered peers */
1074 if (count == 0) /* No peers to select from! */
1076 GNUNET_STATISTICS_update (GDS_stats,
1077 gettext_noop ("# Peer selection failed"), 1,
1081 /* Now actually choose a peer */
1082 selected = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, count);
1084 for (bc = closest_bucket; bc < MAX_BUCKETS; bc++)
1086 pos = k_buckets[bc].head;
1087 while ((pos != NULL) && (count < bucket_size))
1089 if ( (bloom != NULL) &&
1091 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)) )
1094 continue; /* Ignore bloomfiltered peers */
1096 if (0 == selected--)
1107 * Compute the set of peers that the given request should be
1110 * @param key routing key
1111 * @param bloom bloom filter excluding peers as targets, all selected
1112 * peers will be added to the bloom filter
1113 * @param hop_count number of hops the request has traversed so far
1114 * @param target_replication desired number of replicas
1115 * @param targets where to store an array of target peers (to be
1116 * free'd by the caller)
1117 * @return number of peers returned in 'targets'.
1120 get_target_peers (const GNUNET_HashCode *key,
1121 struct GNUNET_CONTAINER_BloomFilter *bloom,
1123 uint32_t target_replication,
1124 struct PeerInfo ***targets)
1128 struct PeerInfo **rtargets;
1129 struct PeerInfo *nxt;
1131 GNUNET_assert (NULL != bloom);
1132 ret = get_forward_count (hop_count, target_replication);
1138 rtargets = GNUNET_malloc (sizeof (struct PeerInfo*) * ret);
1142 nxt = select_peer (key, bloom, hop_count);
1145 rtargets[off++] = nxt;
1146 GNUNET_break (GNUNET_NO ==
1147 GNUNET_CONTAINER_bloomfilter_test (bloom, &nxt->id.hashPubKey));
1148 GNUNET_CONTAINER_bloomfilter_add (bloom, &nxt->id.hashPubKey);
1152 GNUNET_free (rtargets);
1156 *targets = rtargets;
1162 * Perform a PUT operation. Forwards the given request to other
1163 * peers. Does not store the data locally. Does not give the
1164 * data to local clients. May do nothing if this is the only
1165 * peer in the network (or if we are the closest peer in the
1168 * @param type type of the block
1169 * @param options routing options
1170 * @param desired_replication_level desired replication count
1171 * @param expiration_time when does the content expire
1172 * @param hop_count how many hops has this message traversed so far
1173 * @param bf Bloom filter of peers this PUT has already traversed
1174 * @param key key for the content
1175 * @param put_path_length number of entries in put_path
1176 * @param put_path peers this request has traversed so far (if tracked)
1177 * @param data payload to store
1178 * @param data_size number of bytes in data
1181 GDS_NEIGHBOURS_handle_put (enum GNUNET_BLOCK_Type type,
1182 enum GNUNET_DHT_RouteOption options,
1183 uint32_t desired_replication_level,
1184 struct GNUNET_TIME_Absolute expiration_time,
1186 struct GNUNET_CONTAINER_BloomFilter *bf,
1187 const GNUNET_HashCode *key,
1188 unsigned int put_path_length,
1189 struct GNUNET_PeerIdentity *put_path,
1193 unsigned int target_count;
1195 struct PeerInfo **targets;
1196 struct PeerInfo *target;
1197 struct P2PPendingMessage *pending;
1199 struct PeerPutMessage *ppm;
1200 struct GNUNET_PeerIdentity *pp;
1202 GNUNET_assert (NULL != bf);
1203 GNUNET_CONTAINER_bloomfilter_add (bf, &my_identity.hashPubKey);
1204 GNUNET_STATISTICS_update (GDS_stats,
1205 gettext_noop ("# PUT requests routed"), 1,
1207 target_count = get_target_peers (key, bf, hop_count,
1208 desired_replication_level,
1210 if (0 == target_count)
1212 msize = put_path_length * sizeof (struct GNUNET_PeerIdentity) + data_size + sizeof (struct PeerPutMessage);
1213 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1215 put_path_length = 0;
1216 msize = data_size + sizeof (struct PeerPutMessage);
1218 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1223 GNUNET_STATISTICS_update (GDS_stats,
1224 gettext_noop ("# Peers selected as targets for PUT requests"), target_count,
1226 for (i=0;i<target_count;i++)
1228 target = targets[i];
1229 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1230 pending->importance = 0; /* FIXME */
1231 pending->timeout = expiration_time;
1232 ppm = (struct PeerPutMessage*) &pending[1];
1233 pending->msg = &ppm->header;
1234 ppm->header.size = htons (msize);
1235 ppm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_PUT);
1236 ppm->options = htonl (options);
1237 ppm->type = htonl (type);
1238 ppm->hop_count = htonl (hop_count + 1);
1239 ppm->desired_replication_level = htonl (desired_replication_level);
1240 ppm->put_path_length = htonl (put_path_length);
1241 ppm->expiration_time = GNUNET_TIME_absolute_hton (expiration_time);
1242 GNUNET_break (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bf, &target->id.hashPubKey));
1243 GNUNET_assert (GNUNET_OK ==
1244 GNUNET_CONTAINER_bloomfilter_get_raw_data (bf,
1248 pp = (struct GNUNET_PeerIdentity*) &ppm[1];
1249 memcpy (pp, put_path, sizeof (struct GNUNET_PeerIdentity) * put_path_length);
1250 memcpy (&pp[put_path_length], data, data_size);
1251 GNUNET_CONTAINER_DLL_insert_tail (target->head,
1254 target->pending_count++;
1255 process_peer_queue (target);
1257 GNUNET_free (targets);
1262 * Perform a GET operation. Forwards the given request to other
1263 * peers. Does not lookup the key locally. May do nothing if this is
1264 * the only peer in the network (or if we are the closest peer in the
1267 * @param type type of the block
1268 * @param options routing options
1269 * @param desired_replication_level desired replication count
1270 * @param hop_count how many hops did this request traverse so far?
1271 * @param key key for the content
1272 * @param xquery extended query
1273 * @param xquery_size number of bytes in xquery
1274 * @param reply_bf bloomfilter to filter duplicates
1275 * @param reply_bf_mutator mutator for reply_bf
1276 * @param peer_bf filter for peers not to select (again)
1279 GDS_NEIGHBOURS_handle_get (enum GNUNET_BLOCK_Type type,
1280 enum GNUNET_DHT_RouteOption options,
1281 uint32_t desired_replication_level,
1283 const GNUNET_HashCode *key,
1286 const struct GNUNET_CONTAINER_BloomFilter *reply_bf,
1287 uint32_t reply_bf_mutator,
1288 struct GNUNET_CONTAINER_BloomFilter *peer_bf)
1290 unsigned int target_count;
1292 struct PeerInfo **targets;
1293 struct PeerInfo *target;
1294 struct P2PPendingMessage *pending;
1296 struct PeerGetMessage *pgm;
1298 size_t reply_bf_size;
1300 GNUNET_assert (NULL != peer_bf);
1301 GNUNET_CONTAINER_bloomfilter_add (peer_bf, &my_identity.hashPubKey);
1302 GNUNET_STATISTICS_update (GDS_stats,
1303 gettext_noop ("# GET requests routed"), 1,
1305 target_count = get_target_peers (key, peer_bf, hop_count,
1306 desired_replication_level,
1308 if (0 == target_count)
1310 reply_bf_size = GNUNET_CONTAINER_bloomfilter_get_size (reply_bf);
1311 msize = xquery_size + sizeof (struct PeerGetMessage) + reply_bf_size;
1312 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1317 GNUNET_STATISTICS_update (GDS_stats,
1318 gettext_noop ("# Peers selected as targets for GET requests"), target_count,
1320 /* forward request */
1321 for (i=0;i<target_count;i++)
1323 target = targets[i];
1324 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1325 pending->importance = 0; /* FIXME */
1326 pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
1327 pgm = (struct PeerGetMessage*) &pending[1];
1328 pending->msg = &pgm->header;
1329 pgm->header.size = htons (msize);
1330 pgm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_GET);
1331 pgm->options = htonl (options);
1332 pgm->type = htonl (type);
1333 pgm->hop_count = htonl (hop_count + 1);
1334 pgm->desired_replication_level = htonl (desired_replication_level);
1335 pgm->xquery_size = htonl (xquery_size);
1336 pgm->bf_mutator = reply_bf_mutator;
1337 GNUNET_break (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (peer_bf, &target->id.hashPubKey));
1338 GNUNET_assert (GNUNET_OK ==
1339 GNUNET_CONTAINER_bloomfilter_get_raw_data (peer_bf,
1343 xq = (char *) &pgm[1];
1344 memcpy (xq, xquery, xquery_size);
1345 if (NULL != reply_bf)
1346 GNUNET_assert (GNUNET_OK ==
1347 GNUNET_CONTAINER_bloomfilter_get_raw_data (reply_bf,
1350 GNUNET_CONTAINER_DLL_insert_tail (target->head,
1353 target->pending_count++;
1354 process_peer_queue (target);
1356 GNUNET_free (targets);
1361 * Handle a reply (route to origin). Only forwards the reply back to
1362 * the given peer. Does not do local caching or forwarding to local
1365 * @param target neighbour that should receive the block (if still connected)
1366 * @param type type of the block
1367 * @param expiration_time when does the content expire
1368 * @param key key for the content
1369 * @param put_path_length number of entries in put_path
1370 * @param put_path peers the original PUT traversed (if tracked)
1371 * @param get_path_length number of entries in put_path
1372 * @param get_path peers this reply has traversed so far (if tracked)
1373 * @param data payload of the reply
1374 * @param data_size number of bytes in data
1377 GDS_NEIGHBOURS_handle_reply (const struct GNUNET_PeerIdentity *target,
1378 enum GNUNET_BLOCK_Type type,
1379 struct GNUNET_TIME_Absolute expiration_time,
1380 const GNUNET_HashCode *key,
1381 unsigned int put_path_length,
1382 const struct GNUNET_PeerIdentity *put_path,
1383 unsigned int get_path_length,
1384 const struct GNUNET_PeerIdentity *get_path,
1388 struct PeerInfo *pi;
1389 struct P2PPendingMessage *pending;
1391 struct PeerResultMessage *prm;
1392 struct GNUNET_PeerIdentity *paths;
1394 msize = data_size + sizeof (struct PeerResultMessage) +
1395 (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity);
1396 if ( (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE) ||
1397 (get_path_length > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
1398 (put_path_length > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
1399 (data_size > GNUNET_SERVER_MAX_MESSAGE_SIZE) )
1404 pi = GNUNET_CONTAINER_multihashmap_get (all_known_peers,
1405 &target->hashPubKey);
1408 /* peer disconnected in the meantime, drop reply */
1411 GNUNET_STATISTICS_update (GDS_stats,
1412 gettext_noop ("# REPLIES routed"), 1,
1414 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1415 pending->importance = 0; /* FIXME */
1416 pending->timeout = expiration_time;
1417 prm = (struct PeerResultMessage*) &pending[1];
1418 pending->msg = &prm->header;
1419 prm->header.size = htons (msize);
1420 prm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT);
1421 prm->type = htonl (type);
1422 prm->put_path_length = htonl (put_path_length);
1423 prm->get_path_length = htonl (get_path_length);
1424 prm->expiration_time = GNUNET_TIME_absolute_hton (expiration_time);
1426 paths = (struct GNUNET_PeerIdentity*) &prm[1];
1427 memcpy (paths, put_path, put_path_length * sizeof (struct GNUNET_PeerIdentity));
1428 memcpy (&paths[put_path_length],
1429 get_path, get_path_length * sizeof (struct GNUNET_PeerIdentity));
1430 memcpy (&paths[put_path_length + get_path_length],
1432 GNUNET_CONTAINER_DLL_insert (pi->head,
1435 pi->pending_count++;
1436 process_peer_queue (pi);
1441 * To be called on core init/fail.
1443 * @param cls service closure
1444 * @param server handle to the server for this service
1445 * @param identity the public identity of this peer
1446 * @param publicKey the public key of this peer
1449 core_init (void *cls, struct GNUNET_CORE_Handle *server,
1450 const struct GNUNET_PeerIdentity *identity,
1451 const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *publicKey)
1453 GNUNET_assert (server != NULL);
1454 my_identity = *identity;
1459 * Core handler for p2p put requests.
1461 * @param cls closure
1462 * @param peer sender of the request
1463 * @param message message
1464 * @param peer peer identity this notification is about
1465 * @param atsi performance data
1466 * @return GNUNET_OK to keep the connection open,
1467 * GNUNET_SYSERR to close it (signal serious error)
1470 handle_dht_p2p_put (void *cls,
1471 const struct GNUNET_PeerIdentity *peer,
1472 const struct GNUNET_MessageHeader *message,
1473 const struct GNUNET_TRANSPORT_ATS_Information
1476 const struct PeerPutMessage *put;
1477 const struct GNUNET_PeerIdentity *put_path;
1478 const void *payload;
1481 size_t payload_size;
1482 enum GNUNET_DHT_RouteOption options;
1483 struct GNUNET_CONTAINER_BloomFilter *bf;
1484 GNUNET_HashCode test_key;
1486 msize = ntohs (message->size);
1487 if (msize < sizeof (struct PeerPutMessage))
1489 GNUNET_break_op (0);
1492 put = (const struct PeerPutMessage*) message;
1493 putlen = ntohl (put->put_path_length);
1494 if ( (msize < sizeof (struct PeerPutMessage) + putlen * sizeof (struct GNUNET_PeerIdentity)) ||
1495 (putlen > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) )
1497 GNUNET_break_op (0);
1500 GNUNET_STATISTICS_update (GDS_stats,
1501 gettext_noop ("# P2P PUT requests received"), 1,
1503 put_path = (const struct GNUNET_PeerIdentity*) &put[1];
1504 payload = &put_path[putlen];
1505 options = ntohl (put->options);
1506 payload_size = msize - (sizeof (struct PeerPutMessage) +
1507 putlen * sizeof (struct GNUNET_PeerIdentity));
1508 switch (GNUNET_BLOCK_get_key (GDS_block_context,
1510 payload, payload_size,
1514 if (0 != memcmp (&test_key, &put->key, sizeof (GNUNET_HashCode)))
1516 GNUNET_break_op (0);
1521 GNUNET_break_op (0);
1524 /* cannot verify, good luck */
1527 bf = GNUNET_CONTAINER_bloomfilter_init (put->bloomfilter,
1529 GNUNET_CONSTANTS_BLOOMFILTER_K);
1530 GNUNET_break_op (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bf, &peer->hashPubKey));
1532 struct GNUNET_PeerIdentity pp[putlen+1];
1534 /* extend 'put path' by sender */
1535 if (0 != (options & GNUNET_DHT_RO_RECORD_ROUTE))
1537 memcpy (pp, put_path, putlen * sizeof (struct GNUNET_PeerIdentity));
1544 /* give to local clients */
1545 GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (put->expiration_time),
1554 if ( (0 != (options & GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE)) ||
1555 (am_closest_peer (&put->key,
1557 GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (put->expiration_time),
1563 /* route to other peers */
1564 GDS_NEIGHBOURS_handle_put (ntohl (put->type),
1566 ntohl (put->desired_replication_level),
1567 GNUNET_TIME_absolute_ntoh (put->expiration_time),
1568 ntohl (put->hop_count) + 1 /* who adds +1? */,
1575 GNUNET_CONTAINER_bloomfilter_free (bf);
1581 * We have received a FIND PEER request. Send matching
1584 * @param sender sender of the FIND PEER request
1585 * @param key peers close to this key are desired
1586 * @param bf peers matching this bf are excluded
1587 * @param bf_mutator mutator for bf
1590 handle_find_peer (const struct GNUNET_PeerIdentity *sender,
1591 const GNUNET_HashCode *key,
1592 struct GNUNET_CONTAINER_BloomFilter *bf,
1593 uint32_t bf_mutator)
1596 struct PeerBucket *bucket;
1597 struct PeerInfo *peer;
1598 unsigned int choice;
1599 GNUNET_HashCode mhash;
1600 const struct GNUNET_HELLO_Message *hello;
1602 /* first, check about our own HELLO */
1603 if (NULL != GDS_my_hello)
1605 GNUNET_BLOCK_mingle_hash (&my_identity.hashPubKey, bf_mutator, &mhash);
1606 if ( (NULL == bf) ||
1607 (GNUNET_YES != GNUNET_CONTAINER_bloomfilter_test (bf, &mhash)) )
1609 GDS_NEIGHBOURS_handle_reply (sender,
1610 GNUNET_BLOCK_TYPE_DHT_HELLO,
1611 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_HELLO_ADDRESS_EXPIRATION),
1616 GNUNET_HELLO_size ((const struct GNUNET_HELLO_Message*) GDS_my_hello));
1620 GNUNET_STATISTICS_update (GDS_stats,
1621 gettext_noop ("# FIND PEER requests ignored due to Bloomfilter"), 1,
1627 GNUNET_STATISTICS_update (GDS_stats,
1628 gettext_noop ("# FIND PEER requests ignored due to lack of HELLO"), 1,
1632 /* then, also consider sending a random HELLO from the closest bucket */
1633 if (0 == memcmp (&my_identity.hashPubKey, key, sizeof (GNUNET_HashCode)))
1634 bucket_idx = closest_bucket;
1636 bucket_idx = GNUNET_MIN (closest_bucket, find_bucket (key));
1637 if (bucket_idx == GNUNET_SYSERR)
1639 bucket = &k_buckets[bucket_idx];
1640 if (bucket->peers_size == 0)
1642 choice = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
1643 bucket->peers_size);
1644 peer = bucket->head;
1647 GNUNET_assert (peer != NULL);
1650 choice = bucket->peers_size;
1655 return; /* no non-masked peer available */
1657 peer = bucket->head;
1658 GNUNET_BLOCK_mingle_hash (&peer->id.hashPubKey, bf_mutator, &mhash);
1659 hello = GDS_HELLO_get (&peer->id);
1661 while ( (hello == NULL) ||
1662 (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bf, &mhash)) );
1663 GDS_NEIGHBOURS_handle_reply (sender,
1664 GNUNET_BLOCK_TYPE_DHT_HELLO,
1665 GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_HELLO_ADDRESS_EXPIRATION),
1670 GNUNET_HELLO_size (hello));
1675 * Core handler for p2p get requests.
1677 * @param cls closure
1678 * @param peer sender of the request
1679 * @param message message
1680 * @param peer peer identity this notification is about
1681 * @param atsi performance data
1682 * @return GNUNET_OK to keep the connection open,
1683 * GNUNET_SYSERR to close it (signal serious error)
1686 handle_dht_p2p_get (void *cls, const struct GNUNET_PeerIdentity *peer,
1687 const struct GNUNET_MessageHeader *message,
1688 const struct GNUNET_TRANSPORT_ATS_Information
1691 struct PeerGetMessage *get;
1692 uint32_t xquery_size;
1693 size_t reply_bf_size;
1695 enum GNUNET_BLOCK_Type type;
1696 enum GNUNET_DHT_RouteOption options;
1697 enum GNUNET_BLOCK_EvaluationResult eval;
1698 struct GNUNET_CONTAINER_BloomFilter *reply_bf;
1699 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
1702 GNUNET_break (0 != memcmp (peer, &my_identity, sizeof (struct GNUNET_PeerIdentity)));
1703 /* parse and validate message */
1704 msize = ntohs (message->size);
1705 if (msize < sizeof (struct PeerGetMessage))
1707 GNUNET_break_op (0);
1710 get = (struct PeerGetMessage *) message;
1711 xquery_size = ntohl (get->xquery_size);
1712 if (msize < sizeof (struct PeerGetMessage) + xquery_size)
1714 GNUNET_break_op (0);
1717 GNUNET_STATISTICS_update (GDS_stats,
1718 gettext_noop ("# P2P GET requests received"), 1,
1720 reply_bf_size = msize - (sizeof (struct PeerGetMessage) + xquery_size);
1721 type = ntohl (get->type);
1722 options = ntohl (get->options);
1723 xquery = (const char*) &get[1];
1725 if (reply_bf_size > 0)
1726 reply_bf = GNUNET_CONTAINER_bloomfilter_init (&xquery[xquery_size],
1728 GNUNET_CONSTANTS_BLOOMFILTER_K);
1729 eval = GNUNET_BLOCK_evaluate (GDS_block_context,
1734 xquery, xquery_size,
1736 if (eval != GNUNET_BLOCK_EVALUATION_REQUEST_VALID)
1738 /* request invalid or block type not supported */
1739 GNUNET_break_op (eval == GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED);
1740 if (NULL != reply_bf)
1741 GNUNET_CONTAINER_bloomfilter_free (reply_bf);
1745 GNUNET_CONTAINER_bloomfilter_init (get->bloomfilter,
1747 GNUNET_CONSTANTS_BLOOMFILTER_K);
1748 GNUNET_break_op (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (peer_bf, &peer->hashPubKey));
1749 /* remember request for routing replies */
1750 GDS_ROUTING_add (peer,
1754 xquery, xquery_size,
1755 reply_bf, get->bf_mutator);
1757 /* local lookup (this may update the reply_bf) */
1758 if ( (0 != (options & GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE)) ||
1759 (am_closest_peer (&get->key,
1762 if ( (0 != (options & GNUNET_DHT_RO_FIND_PEER)))
1764 GNUNET_STATISTICS_update (GDS_stats,
1765 gettext_noop ("# P2P FIND PEER requests processed"), 1,
1767 handle_find_peer (peer,
1774 eval = GDS_DATACACHE_handle_get (&get->key,
1776 xquery, xquery_size,
1783 GNUNET_STATISTICS_update (GDS_stats,
1784 gettext_noop ("# P2P GET requests ONLY routed"), 1,
1788 /* P2P forwarding */
1789 if (eval != GNUNET_BLOCK_EVALUATION_OK_LAST)
1790 GDS_NEIGHBOURS_handle_get (type,
1792 ntohl (get->desired_replication_level),
1793 ntohl (get->hop_count) + 1, /* CHECK: where (else) do we do +1? */
1795 xquery, xquery_size,
1800 if (NULL != reply_bf)
1801 GNUNET_CONTAINER_bloomfilter_free (reply_bf);
1802 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
1808 * Core handler for p2p result messages.
1810 * @param cls closure
1811 * @param message message
1812 * @param peer peer identity this notification is about
1813 * @param atsi performance data
1814 * @return GNUNET_YES (do not cut p2p connection)
1817 handle_dht_p2p_result (void *cls, const struct GNUNET_PeerIdentity *peer,
1818 const struct GNUNET_MessageHeader *message,
1819 const struct GNUNET_TRANSPORT_ATS_Information
1822 const struct PeerResultMessage *prm;
1823 const struct GNUNET_PeerIdentity *put_path;
1824 const struct GNUNET_PeerIdentity *get_path;
1826 uint32_t get_path_length;
1827 uint32_t put_path_length;
1830 enum GNUNET_BLOCK_Type type;
1832 /* parse and validate message */
1833 msize = ntohs (message->size);
1834 if (msize < sizeof (struct PeerResultMessage))
1836 GNUNET_break_op (0);
1839 prm = (struct PeerResultMessage *) message;
1840 put_path_length = ntohl (prm->put_path_length);
1841 get_path_length = ntohl (prm->get_path_length);
1842 if ( (msize < sizeof (struct PeerResultMessage) +
1843 (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity)) ||
1844 (get_path_length > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
1845 (put_path_length > GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) )
1847 GNUNET_break_op (0);
1850 GNUNET_STATISTICS_update (GDS_stats,
1851 gettext_noop ("# P2P RESULTS received"), 1,
1853 put_path = (const struct GNUNET_PeerIdentity*) &prm[1];
1854 get_path = &put_path[put_path_length];
1855 type = ntohl (prm->type);
1856 data = (const void*) &get_path[get_path_length];
1857 data_size = msize - (sizeof (struct PeerResultMessage) +
1858 (get_path_length + put_path_length) * sizeof (struct GNUNET_PeerIdentity));
1860 /* if we got a HELLO, consider it for our own routing table */
1861 if (type == GNUNET_BLOCK_TYPE_DHT_HELLO)
1863 const struct GNUNET_MessageHeader *h;
1864 struct GNUNET_PeerIdentity pid;
1867 /* Should be a HELLO, validate and consider using it! */
1868 if (data_size < sizeof (struct GNUNET_MessageHeader))
1870 GNUNET_break_op (0);
1874 if (data_size != ntohs (h->size))
1876 GNUNET_break_op (0);
1880 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message*) h,
1883 GNUNET_break_op (0);
1886 if (0 != memcmp (&my_identity, &pid, sizeof (struct GNUNET_PeerIdentity)))
1888 bucket = find_bucket (&pid.hashPubKey);
1889 if ( (bucket >= 0) &&
1890 (k_buckets[bucket].peers_size < bucket_size) )
1892 if (NULL != GDS_transport_handle)
1893 GNUNET_TRANSPORT_offer_hello (GDS_transport_handle,
1895 (void) GNUNET_CORE_peer_request_connect (coreAPI,
1902 /* append 'peer' to 'get_path' */
1904 struct GNUNET_PeerIdentity xget_path[get_path_length+1];
1906 memcpy (xget_path, get_path, get_path_length * sizeof (struct GNUNET_PeerIdentity));
1907 xget_path[get_path_length] = *peer;
1910 /* forward to local clients */
1911 GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (prm->expiration_time),
1921 /* forward to other peers */
1922 GDS_ROUTING_process (type,
1923 GNUNET_TIME_absolute_ntoh (prm->expiration_time),
1937 * Initialize neighbours subsystem.
1939 * @return GNUNET_OK on success, GNUNET_SYSERR on error
1942 GDS_NEIGHBOURS_init ()
1944 static struct GNUNET_CORE_MessageHandler core_handlers[] = {
1945 {&handle_dht_p2p_get, GNUNET_MESSAGE_TYPE_DHT_P2P_GET, 0},
1946 {&handle_dht_p2p_put, GNUNET_MESSAGE_TYPE_DHT_P2P_PUT, 0},
1947 {&handle_dht_p2p_result, GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT, 0},
1950 unsigned long long temp_config_num;
1953 GNUNET_CONFIGURATION_get_value_number (GDS_cfg, "DHT", "bucket_size",
1955 bucket_size = (unsigned int) temp_config_num;
1956 coreAPI = GNUNET_CORE_connect (GDS_cfg,
1960 &handle_core_connect,
1961 &handle_core_disconnect,
1962 NULL, /* Do we care about "status" updates? */
1966 if (coreAPI == NULL)
1967 return GNUNET_SYSERR;
1968 all_known_peers = GNUNET_CONTAINER_multihashmap_create (256);
1974 * Shutdown neighbours subsystem.
1977 GDS_NEIGHBOURS_done ()
1979 if (coreAPI == NULL)
1981 GNUNET_CORE_disconnect (coreAPI);
1983 GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (all_known_peers));
1984 GNUNET_CONTAINER_multihashmap_destroy (all_known_peers);
1985 all_known_peers = NULL;
1986 if (GNUNET_SCHEDULER_NO_TASK != find_peer_task)
1988 GNUNET_SCHEDULER_cancel (find_peer_task);
1989 find_peer_task = GNUNET_SCHEDULER_NO_TASK;
1994 /* end of gnunet-service-dht_neighbours.c */