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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
28 #include "gnunet_util_lib.h"
29 #include "gnunet_block_lib.h"
30 #include "gnunet_hello_lib.h"
31 #include "gnunet_constants.h"
32 #include "gnunet_protocols.h"
33 #include "gnunet_nse_service.h"
34 #include "gnunet_ats_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"
50 #define LOG_TRAFFIC(kind,...) GNUNET_log_from (kind, "dht-traffic",__VA_ARGS__)
53 * How many buckets will we allow total.
55 #define MAX_BUCKETS sizeof (struct GNUNET_HashCode) * 8
58 * What is the maximum number of peers in a given bucket.
60 #define DEFAULT_BUCKET_SIZE 8
63 * Desired replication level for FIND PEER requests
65 #define FIND_PEER_REPLICATION_LEVEL 4
68 * Maximum allowed replication level for all requests.
70 #define MAXIMUM_REPLICATION_LEVEL 16
73 * Maximum allowed number of pending messages per peer.
75 #define MAXIMUM_PENDING_PER_PEER 64
78 * How long at least to wait before sending another find peer request.
80 #define DHT_MINIMUM_FIND_PEER_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 30)
83 * How long at most to wait before sending another find peer request.
85 #define DHT_MAXIMUM_FIND_PEER_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 10)
88 * How long at most to wait for transmission of a GET request to another peer?
90 #define GET_TIMEOUT GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 2)
93 * Hello address expiration
95 extern struct GNUNET_TIME_Relative hello_expiration;
98 GNUNET_NETWORK_STRUCT_BEGIN
103 struct PeerPutMessage
106 * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_PUT
108 struct GNUNET_MessageHeader header;
113 uint32_t options GNUNET_PACKED;
118 uint32_t type GNUNET_PACKED;
123 uint32_t hop_count GNUNET_PACKED;
126 * Replication level for this message
128 uint32_t desired_replication_level GNUNET_PACKED;
131 * Length of the PUT path that follows (if tracked).
133 uint32_t put_path_length GNUNET_PACKED;
136 * When does the content expire?
138 struct GNUNET_TIME_AbsoluteNBO expiration_time;
141 * Bloomfilter (for peer identities) to stop circular routes
143 char bloomfilter[DHT_BLOOM_SIZE];
146 * The key we are storing under.
148 struct GNUNET_HashCode key;
150 /* put path (if tracked) */
160 struct PeerResultMessage
163 * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT
165 struct GNUNET_MessageHeader header;
170 uint32_t type GNUNET_PACKED;
173 * Length of the PUT path that follows (if tracked).
175 uint32_t put_path_length GNUNET_PACKED;
178 * Length of the GET path that follows (if tracked).
180 uint32_t get_path_length GNUNET_PACKED;
183 * When does the content expire?
185 struct GNUNET_TIME_AbsoluteNBO expiration_time;
188 * The key of the corresponding GET request.
190 struct GNUNET_HashCode key;
192 /* put path (if tracked) */
194 /* get path (if tracked) */
204 struct PeerGetMessage
207 * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_GET
209 struct GNUNET_MessageHeader header;
214 uint32_t options GNUNET_PACKED;
217 * Desired content type.
219 uint32_t type GNUNET_PACKED;
224 uint32_t hop_count GNUNET_PACKED;
227 * Desired replication level for this request.
229 uint32_t desired_replication_level GNUNET_PACKED;
232 * Size of the extended query.
234 uint32_t xquery_size;
237 * Bloomfilter mutator.
242 * Bloomfilter (for peer identities) to stop circular routes
244 char bloomfilter[DHT_BLOOM_SIZE];
247 * The key we are looking for.
249 struct GNUNET_HashCode key;
253 /* result bloomfilter */
256 GNUNET_NETWORK_STRUCT_END
259 * Linked list of messages to send to a particular other peer.
261 struct P2PPendingMessage
264 * Pointer to next item in the list
266 struct P2PPendingMessage *next;
269 * Pointer to previous item in the list
271 struct P2PPendingMessage *prev;
274 * Message importance level. FIXME: used? useful?
276 unsigned int importance;
279 * When does this message time out?
281 struct GNUNET_TIME_Absolute timeout;
284 * Actual message to be sent, allocated at the end of the struct:
285 * // msg = (cast) &pm[1];
286 * // memcpy (&pm[1], data, len);
288 const struct GNUNET_MessageHeader *msg;
294 * Entry for a peer in a bucket.
299 * Next peer entry (DLL)
301 struct PeerInfo *next;
304 * Prev peer entry (DLL)
306 struct PeerInfo *prev;
309 * Count of outstanding messages for peer.
311 unsigned int pending_count;
314 * Head of pending messages to be sent to this peer.
316 struct P2PPendingMessage *head;
319 * Tail of pending messages to be sent to this peer.
321 struct P2PPendingMessage *tail;
324 * Core handle for sending messages to this peer.
326 struct GNUNET_CORE_TransmitHandle *th;
329 * What is the identity of the peer?
331 struct GNUNET_PeerIdentity id;
335 * What is the average latency for replies received?
337 struct GNUNET_TIME_Relative latency;
340 * Transport level distance to peer.
342 unsigned int distance;
349 * Peers are grouped into buckets.
356 struct PeerInfo *head;
361 struct PeerInfo *tail;
364 * Number of peers in the bucket.
366 unsigned int peers_size;
371 * Information about a peer that we would like to connect to.
377 * Handle to active HELLO offer operation, or NULL.
379 struct GNUNET_TRANSPORT_OfferHelloHandle *oh;
382 * Handle to active connectivity suggestion operation, or NULL.
384 struct GNUNET_ATS_ConnectivitySuggestHandle *sh;
387 * How much would we like to connect to this peer?
394 * Do we cache all results that we are routing in the local datacache?
396 static int cache_results;
399 * Should routing details be logged to stderr (for debugging)?
401 static int log_route_details_stderr;
404 * The lowest currently used bucket, initially 0 (for 0-bits matching bucket).
406 static unsigned int closest_bucket;
409 * How many peers have we added since we sent out our last
412 static unsigned int newly_found_peers;
415 * Option for testing that disables the 'connect' function of the DHT.
417 static int disable_try_connect;
420 * The buckets. Array of size #MAX_BUCKETS. Offset 0 means 0 bits matching.
422 static struct PeerBucket k_buckets[MAX_BUCKETS];
425 * Hash map of all CORE-connected peers, for easy removal from
426 * #k_buckets on disconnect. Values are of type `struct PeerInfo`.
428 static struct GNUNET_CONTAINER_MultiPeerMap *all_connected_peers;
431 * Hash map of all peers we would like to be connected to.
432 * Values are of type `struct ConnectInfo`.
434 static struct GNUNET_CONTAINER_MultiPeerMap *all_desired_peers;
437 * Maximum size for each bucket.
439 static unsigned int bucket_size = DEFAULT_BUCKET_SIZE;
442 * Task that sends FIND PEER requests.
444 static struct GNUNET_SCHEDULER_Task *find_peer_task;
447 * Identity of this peer.
449 static struct GNUNET_PeerIdentity my_identity;
452 * Hash of the identity of this peer.
454 static struct GNUNET_HashCode my_identity_hash;
459 static struct GNUNET_CORE_Handle *core_api;
462 * Handle to ATS connectivity.
464 static struct GNUNET_ATS_ConnectivityHandle *ats_ch;
468 * Find the optimal bucket for this key.
470 * @param hc the hashcode to compare our identity to
471 * @return the proper bucket index, or GNUNET_SYSERR
472 * on error (same hashcode)
475 find_bucket (const struct GNUNET_HashCode *hc)
479 bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity_hash, hc);
480 if (bits == MAX_BUCKETS)
482 /* How can all bits match? Got my own ID? */
484 return GNUNET_SYSERR;
486 return MAX_BUCKETS - bits - 1;
491 * Function called when #GNUNET_TRANSPORT_offer_hello() is done.
492 * Clean up the "oh" field in the @a cls
494 * @param cls a `struct ConnectInfo`
497 offer_hello_done (void *cls)
499 struct ConnectInfo *ci = cls;
506 * Function called for all entries in #all_desired_peers to clean up.
509 * @param peer peer the entry is for
510 * @param value the value to remove
511 * @return #GNUNET_YES
514 free_connect_info (void *cls,
515 const struct GNUNET_PeerIdentity *peer,
518 struct ConnectInfo *ci = value;
520 GNUNET_assert (GNUNET_YES ==
521 GNUNET_CONTAINER_multipeermap_remove (all_desired_peers,
526 GNUNET_ATS_connectivity_suggest_cancel (ci->sh);
531 GNUNET_TRANSPORT_offer_hello_cancel (ci->oh);
540 * Consider if we want to connect to a given peer, and if so
541 * let ATS know. If applicable, the HELLO is offered to the
544 * @param pid peer to consider connectivity requirements for
545 * @param h a HELLO message, or NULL
548 try_connect (const struct GNUNET_PeerIdentity *pid,
549 const struct GNUNET_MessageHeader *h)
552 struct GNUNET_HashCode pid_hash;
553 struct ConnectInfo *ci;
556 GNUNET_CRYPTO_hash (pid,
557 sizeof (struct GNUNET_PeerIdentity),
559 bucket = find_bucket (&pid_hash);
562 ci = GNUNET_CONTAINER_multipeermap_get (all_desired_peers,
565 if (k_buckets[bucket].peers_size < bucket_size)
566 strength = (bucket_size - k_buckets[bucket].peers_size) * bucket;
568 strength = bucket; /* minimum value of connectivity */
570 GNUNET_CONTAINER_multipeermap_contains (all_connected_peers,
572 strength *= 2; /* double for connected peers */
573 else if (k_buckets[bucket].peers_size > bucket_size)
574 strength = 0; /* bucket full, we really do not care about more */
576 if ( (0 == strength) &&
579 /* release request */
580 GNUNET_assert (GNUNET_YES ==
581 free_connect_info (NULL,
588 ci = GNUNET_new (struct ConnectInfo);
589 GNUNET_assert (GNUNET_OK ==
590 GNUNET_CONTAINER_multipeermap_put (all_desired_peers,
593 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
595 if ( (NULL != GDS_transport_handle) &&
598 GNUNET_TRANSPORT_offer_hello_cancel (ci->oh);
599 if ( (NULL != GDS_transport_handle) &&
601 ci->oh = GNUNET_TRANSPORT_offer_hello (GDS_transport_handle,
605 if ( (NULL != ci->sh) &&
606 (ci->strength != strength) )
607 GNUNET_ATS_connectivity_suggest_cancel (ci->sh);
608 if (ci->strength != strength)
609 ci->sh = GNUNET_ATS_connectivity_suggest (ats_ch,
612 ci->strength = strength;
617 * Function called for each peer in #all_desired_peers during
618 * #update_connect_preferences() if we have reason to adjust
619 * the strength of our desire to keep connections to certain
620 * peers. Calls #try_connect() to update the calculations for
624 * @param pid peer to update
625 * @param value unused
626 * @return #GNUNET_YES (continue to iterate)
629 update_desire_strength (void *cls,
630 const struct GNUNET_PeerIdentity *pid,
633 try_connect (pid, NULL);
639 * Update our preferences for connectivity as given to ATS.
641 * @param cls the `struct PeerInfo` of the peer
642 * @param tc scheduler context.
645 update_connect_preferences ()
647 GNUNET_CONTAINER_multipeermap_iterate (all_desired_peers,
648 &update_desire_strength,
654 * Closure for #add_known_to_bloom().
656 struct BloomConstructorContext
659 * Bloom filter under construction.
661 struct GNUNET_CONTAINER_BloomFilter *bloom;
671 * Add each of the peers we already know to the bloom filter of
672 * the request so that we don't get duplicate HELLOs.
674 * @param cls the 'struct BloomConstructorContext'.
675 * @param key peer identity to add to the bloom filter
676 * @param value value the peer information (unused)
677 * @return #GNUNET_YES (we should continue to iterate)
680 add_known_to_bloom (void *cls,
681 const struct GNUNET_PeerIdentity *key,
684 struct BloomConstructorContext *ctx = cls;
685 struct GNUNET_HashCode key_hash;
686 struct GNUNET_HashCode mh;
688 GNUNET_CRYPTO_hash (key,
689 sizeof (struct GNUNET_PeerIdentity),
691 GNUNET_BLOCK_mingle_hash (&key_hash,
694 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
695 "Adding known peer (%s) to bloomfilter for FIND PEER with mutation %u\n",
696 GNUNET_i2s (key), ctx->bf_mutator);
697 GNUNET_CONTAINER_bloomfilter_add (ctx->bloom, &mh);
703 * Task to send a find peer message for our own peer identifier
704 * so that we can find the closest peers in the network to ourselves
705 * and attempt to connect to them.
707 * @param cls closure for this task
710 send_find_peer_message (void *cls)
712 struct GNUNET_TIME_Relative next_send_time;
713 struct BloomConstructorContext bcc;
714 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
716 find_peer_task = NULL;
717 if (newly_found_peers > bucket_size)
719 /* If we are finding many peers already, no need to send out our request right now! */
721 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES,
722 &send_find_peer_message,
724 newly_found_peers = 0;
728 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK,
731 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
732 GNUNET_CONSTANTS_BLOOMFILTER_K);
733 GNUNET_CONTAINER_multipeermap_iterate (all_connected_peers,
736 GNUNET_STATISTICS_update (GDS_stats,
737 gettext_noop ("# FIND PEER messages initiated"),
741 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
742 GNUNET_CONSTANTS_BLOOMFILTER_K);
743 // FIXME: pass priority!?
744 GDS_NEIGHBOURS_handle_get (GNUNET_BLOCK_TYPE_DHT_HELLO,
745 GNUNET_DHT_RO_FIND_PEER,
746 FIND_PEER_REPLICATION_LEVEL, 0,
747 &my_identity_hash, NULL, 0, bcc.bloom,
748 bcc.bf_mutator, peer_bf);
749 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
750 GNUNET_CONTAINER_bloomfilter_free (bcc.bloom);
751 /* schedule next round */
752 next_send_time.rel_value_us =
753 DHT_MINIMUM_FIND_PEER_INTERVAL.rel_value_us +
754 GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK,
755 DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value_us /
756 (newly_found_peers + 1));
757 newly_found_peers = 0;
758 GNUNET_assert (NULL == find_peer_task);
760 GNUNET_SCHEDULER_add_delayed (next_send_time,
761 &send_find_peer_message,
767 * Method called whenever a peer connects.
770 * @param peer peer identity this notification is about
773 handle_core_connect (void *cls,
774 const struct GNUNET_PeerIdentity *peer)
776 struct PeerInfo *ret;
777 struct GNUNET_HashCode phash;
780 /* Check for connect to self message */
781 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
783 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
787 GNUNET_CONTAINER_multipeermap_contains (all_connected_peers,
793 GNUNET_STATISTICS_update (GDS_stats,
794 gettext_noop ("# peers connected"),
797 GNUNET_CRYPTO_hash (peer,
798 sizeof (struct GNUNET_PeerIdentity),
800 peer_bucket = find_bucket (&phash);
801 GNUNET_assert ((peer_bucket >= 0) && (peer_bucket < MAX_BUCKETS));
802 ret = GNUNET_new (struct PeerInfo);
804 ret->latency = latency;
805 ret->distance = distance;
808 GNUNET_CONTAINER_DLL_insert_tail (k_buckets[peer_bucket].head,
809 k_buckets[peer_bucket].tail,
811 k_buckets[peer_bucket].peers_size++;
812 closest_bucket = GNUNET_MAX (closest_bucket,
814 GNUNET_assert (GNUNET_OK ==
815 GNUNET_CONTAINER_multipeermap_put (all_connected_peers,
818 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
819 if ( (peer_bucket > 0) &&
820 (k_buckets[peer_bucket].peers_size <= bucket_size))
822 update_connect_preferences ();
825 if ( (1 == GNUNET_CONTAINER_multipeermap_size (all_connected_peers)) &&
826 (GNUNET_YES != disable_try_connect))
828 /* got a first connection, good time to start with FIND PEER requests... */
829 GNUNET_assert (NULL == find_peer_task);
830 find_peer_task = GNUNET_SCHEDULER_add_now (&send_find_peer_message,
837 * Method called whenever a peer disconnects.
840 * @param peer peer identity this notification is about
843 handle_core_disconnect (void *cls,
844 const struct GNUNET_PeerIdentity *peer)
846 struct PeerInfo *to_remove;
848 struct P2PPendingMessage *pos;
849 unsigned int discarded;
850 struct GNUNET_HashCode phash;
852 /* Check for disconnect from self message */
853 if (0 == memcmp (&my_identity,
855 sizeof (struct GNUNET_PeerIdentity)))
857 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
861 GNUNET_CONTAINER_multipeermap_get (all_connected_peers,
863 if (NULL == to_remove)
868 GNUNET_STATISTICS_update (GDS_stats,
869 gettext_noop ("# peers connected"),
872 GNUNET_assert (GNUNET_YES ==
873 GNUNET_CONTAINER_multipeermap_remove (all_connected_peers,
876 if ( (0 == GNUNET_CONTAINER_multipeermap_size (all_connected_peers) &&
877 (GNUNET_YES != disable_try_connect)) )
879 GNUNET_SCHEDULER_cancel (find_peer_task);
880 find_peer_task = NULL;
882 GNUNET_CRYPTO_hash (peer,
883 sizeof (struct GNUNET_PeerIdentity),
885 current_bucket = find_bucket (&phash);
886 GNUNET_assert (current_bucket >= 0);
887 GNUNET_CONTAINER_DLL_remove (k_buckets[current_bucket].head,
888 k_buckets[current_bucket].tail,
890 GNUNET_assert (k_buckets[current_bucket].peers_size > 0);
891 k_buckets[current_bucket].peers_size--;
892 while ( (closest_bucket > 0) &&
893 (0 == k_buckets[closest_bucket].peers_size) )
895 if (NULL != to_remove->th)
897 GNUNET_CORE_notify_transmit_ready_cancel (to_remove->th);
898 to_remove->th = NULL;
901 while (NULL != (pos = to_remove->head))
903 GNUNET_CONTAINER_DLL_remove (to_remove->head,
906 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
907 "Dropping message of type %u due to disconnect\n",
908 ntohs (pos->msg->type));
912 if (k_buckets[current_bucket].peers_size < bucket_size)
913 update_connect_preferences ();
914 GNUNET_STATISTICS_update (GDS_stats,
915 gettext_noop ("# Queued messages discarded (peer disconnected)"),
918 GNUNET_free (to_remove);
923 * Called when core is ready to send a message we asked for
924 * out to the destination.
926 * @param cls the 'struct PeerInfo' of the target peer
927 * @param size number of bytes available in @a buf
928 * @param buf where the callee should write the message
929 * @return number of bytes written to @a buf
932 core_transmit_notify (void *cls,
936 struct PeerInfo *peer = cls;
938 struct P2PPendingMessage *pending;
942 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
943 "DHT ctn called with buffer of %u bytes\n",
944 (unsigned int) size);
946 while ((NULL != (pending = peer->head)) &&
947 (0 == GNUNET_TIME_absolute_get_remaining (pending->timeout).rel_value_us))
949 GNUNET_STATISTICS_update (GDS_stats,
951 ("# Messages dropped (CORE timeout)"),
954 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
955 "Dropping message of type %u due to timeout\n",
956 ntohs (pending->msg->type));
957 peer->pending_count--;
958 GNUNET_CONTAINER_DLL_remove (peer->head,
961 GNUNET_free (pending);
965 /* no messages pending */
966 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
967 "No messages pending\n");
972 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
973 "Got NULL buffer, trying again\n");
975 GNUNET_CORE_notify_transmit_ready (core_api, GNUNET_NO,
976 GNUNET_CORE_PRIO_BEST_EFFORT,
977 GNUNET_TIME_absolute_get_remaining
980 ntohs (pending->msg->size),
981 &core_transmit_notify,
983 GNUNET_break (NULL != peer->th);
987 while ((NULL != (pending = peer->head)) &&
988 (size - off >= (msize = ntohs (pending->msg->size))))
990 GNUNET_STATISTICS_update (GDS_stats,
992 ("# Bytes transmitted to other peers"), msize,
994 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
995 "Transmitting message of type %u to %s\n",
996 ntohs (pending->msg->type),
997 GNUNET_i2s (&peer->id));
1002 peer->pending_count--;
1003 GNUNET_CONTAINER_DLL_remove (peer->head,
1006 GNUNET_free (pending);
1008 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1009 "%u bytes fit in %u bytes available, next message is %u bytes\n",
1011 (unsigned int) size,
1012 (NULL != peer->head) ? ntohs (peer->head->msg->size) : 0);
1013 if (NULL != (pending = peer->head))
1015 /* technically redundant, but easier to read and
1016 avoids bogus gcc warning... */
1017 msize = ntohs (pending->msg->size);
1019 GNUNET_CORE_notify_transmit_ready (core_api,
1021 GNUNET_CORE_PRIO_BEST_EFFORT,
1022 GNUNET_TIME_absolute_get_remaining (pending->timeout),
1025 &core_transmit_notify,
1027 GNUNET_break (NULL != peer->th);
1034 * Transmit all messages in the peer's message queue.
1036 * @param peer message queue to process
1039 process_peer_queue (struct PeerInfo *peer)
1041 struct P2PPendingMessage *pending;
1043 if (NULL == (pending = peer->head))
1045 if (NULL != peer->th)
1047 GNUNET_CORE_notify_transmit_ready_cancel (peer->th);
1050 GNUNET_STATISTICS_update (GDS_stats,
1052 ("# Bytes of bandwidth requested from core"),
1053 ntohs (pending->msg->size), GNUNET_NO);
1055 GNUNET_CORE_notify_transmit_ready (core_api, GNUNET_NO,
1056 GNUNET_CORE_PRIO_BEST_EFFORT,
1057 GNUNET_TIME_absolute_get_remaining
1060 ntohs (pending->msg->size),
1061 &core_transmit_notify,
1063 GNUNET_break (NULL != peer->th);
1068 * To how many peers should we (on average) forward the request to
1069 * obtain the desired target_replication count (on average).
1071 * @param hop_count number of hops the message has traversed
1072 * @param target_replication the number of total paths desired
1073 * @return Some number of peers to forward the message to
1076 get_forward_count (uint32_t hop_count, uint32_t target_replication)
1078 uint32_t random_value;
1079 uint32_t forward_count;
1082 if (hop_count > GDS_NSE_get () * 4.0)
1084 /* forcefully terminate */
1085 GNUNET_STATISTICS_update (GDS_stats,
1086 gettext_noop ("# requests TTL-dropped"),
1090 if (hop_count > GDS_NSE_get () * 2.0)
1092 /* Once we have reached our ideal number of hops, only forward to 1 peer */
1095 /* bound by system-wide maximum */
1096 target_replication =
1097 GNUNET_MIN (MAXIMUM_REPLICATION_LEVEL, target_replication);
1099 1 + (target_replication - 1.0) / (GDS_NSE_get () +
1100 ((float) (target_replication - 1.0) *
1102 /* Set forward count to floor of target_value */
1103 forward_count = (uint32_t) target_value;
1104 /* Subtract forward_count (floor) from target_value (yields value between 0 and 1) */
1105 target_value = target_value - forward_count;
1107 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, UINT32_MAX);
1108 if (random_value < (target_value * UINT32_MAX))
1110 return forward_count;
1115 * Compute the distance between have and target as a 32-bit value.
1116 * Differences in the lower bits must count stronger than differences
1117 * in the higher bits.
1121 * @return 0 if have==target, otherwise a number
1122 * that is larger as the distance between
1123 * the two hash codes increases
1126 get_distance (const struct GNUNET_HashCode *target,
1127 const struct GNUNET_HashCode *have)
1129 unsigned int bucket;
1134 /* We have to represent the distance between two 2^9 (=512)-bit
1135 * numbers as a 2^5 (=32)-bit number with "0" being used for the
1136 * two numbers being identical; furthermore, we need to
1137 * guarantee that a difference in the number of matching
1138 * bits is always represented in the result.
1140 * We use 2^32/2^9 numerical values to distinguish between
1141 * hash codes that have the same LSB bit distance and
1142 * use the highest 2^9 bits of the result to signify the
1143 * number of (mis)matching LSB bits; if we have 0 matching
1144 * and hence 512 mismatching LSB bits we return -1 (since
1145 * 512 itself cannot be represented with 9 bits) */
1147 /* first, calculate the most significant 9 bits of our
1148 * result, aka the number of LSBs */
1149 bucket = GNUNET_CRYPTO_hash_matching_bits (target, have);
1150 /* bucket is now a value between 0 and 512 */
1152 return 0; /* perfect match */
1154 return (unsigned int) -1; /* LSB differs; use max (if we did the bit-shifting
1155 * below, we'd end up with max+1 (overflow)) */
1157 /* calculate the most significant bits of the final result */
1158 msb = (512 - bucket) << (32 - 9);
1159 /* calculate the 32-9 least significant bits of the final result by
1160 * looking at the differences in the 32-9 bits following the
1161 * mismatching bit at 'bucket' */
1163 for (i = bucket + 1;
1164 (i < sizeof (struct GNUNET_HashCode) * 8) && (i < bucket + 1 + 32 - 9); i++)
1166 if (GNUNET_CRYPTO_hash_get_bit (target, i) !=
1167 GNUNET_CRYPTO_hash_get_bit (have, i))
1168 lsb |= (1 << (bucket + 32 - 9 - i)); /* first bit set will be 10,
1169 * last bit set will be 31 -- if
1170 * i does not reach 512 first... */
1177 * Check whether my identity is closer than any known peers. If a
1178 * non-null bloomfilter is given, check if this is the closest peer
1179 * that hasn't already been routed to.
1181 * @param key hash code to check closeness to
1182 * @param bloom bloomfilter, exclude these entries from the decision
1183 * @return #GNUNET_YES if node location is closest,
1184 * #GNUNET_NO otherwise.
1187 am_closest_peer (const struct GNUNET_HashCode *key,
1188 const struct GNUNET_CONTAINER_BloomFilter *bloom)
1194 struct PeerInfo *pos;
1195 struct GNUNET_HashCode phash;
1197 if (0 == memcmp (&my_identity_hash, key, sizeof (struct GNUNET_HashCode)))
1199 bucket_num = find_bucket (key);
1200 GNUNET_assert (bucket_num >= 0);
1201 bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity_hash, key);
1202 pos = k_buckets[bucket_num].head;
1204 while ((NULL != pos) && (count < bucket_size))
1206 GNUNET_CRYPTO_hash (&pos->id,
1207 sizeof (struct GNUNET_PeerIdentity),
1209 if ((NULL != bloom) &&
1211 GNUNET_CONTAINER_bloomfilter_test (bloom, &phash)))
1214 continue; /* Skip already checked entries */
1216 other_bits = GNUNET_CRYPTO_hash_matching_bits (&phash, key);
1217 if (other_bits > bits)
1219 if (other_bits == bits) /* We match the same number of bits */
1223 /* No peers closer, we are the closest! */
1229 * Select a peer from the routing table that would be a good routing
1230 * destination for sending a message for "key". The resulting peer
1231 * must not be in the set of blocked peers.<p>
1233 * Note that we should not ALWAYS select the closest peer to the
1234 * target, peers further away from the target should be chosen with
1235 * exponentially declining probability.
1237 * FIXME: double-check that this is fine
1240 * @param key the key we are selecting a peer to route to
1241 * @param bloom a bloomfilter containing entries this request has seen already
1242 * @param hops how many hops has this message traversed thus far
1243 * @return Peer to route to, or NULL on error
1245 static struct PeerInfo *
1246 select_peer (const struct GNUNET_HashCode *key,
1247 const struct GNUNET_CONTAINER_BloomFilter *bloom,
1252 unsigned int selected;
1253 struct PeerInfo *pos;
1255 unsigned int smallest_distance;
1256 struct PeerInfo *chosen;
1257 struct GNUNET_HashCode phash;
1259 if (hops >= GDS_NSE_get ())
1261 /* greedy selection (closest peer that is not in bloomfilter) */
1262 smallest_distance = UINT_MAX;
1264 for (bc = 0; bc <= closest_bucket; bc++)
1266 pos = k_buckets[bc].head;
1268 while ((pos != NULL) && (count < bucket_size))
1270 GNUNET_CRYPTO_hash (&pos->id,
1271 sizeof (struct GNUNET_PeerIdentity),
1273 if ((bloom == NULL) ||
1275 GNUNET_CONTAINER_bloomfilter_test (bloom, &phash)))
1277 dist = get_distance (key, &phash);
1278 if (dist < smallest_distance)
1281 smallest_distance = dist;
1286 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1287 "Excluded peer `%s' due to BF match in greedy routing for %s\n",
1288 GNUNET_i2s (&pos->id), GNUNET_h2s (key));
1289 GNUNET_STATISTICS_update (GDS_stats,
1291 ("# Peers excluded from routing due to Bloomfilter"),
1293 dist = get_distance (key, &phash);
1294 if (dist < smallest_distance)
1297 smallest_distance = dist;
1305 GNUNET_STATISTICS_update (GDS_stats,
1306 gettext_noop ("# Peer selection failed"), 1,
1311 /* select "random" peer */
1312 /* count number of peers that are available and not filtered */
1314 for (bc = 0; bc <= closest_bucket; bc++)
1316 pos = k_buckets[bc].head;
1317 while ((pos != NULL) && (count < bucket_size))
1319 GNUNET_CRYPTO_hash (&pos->id,
1320 sizeof (struct GNUNET_PeerIdentity),
1322 if ((bloom != NULL) &&
1324 GNUNET_CONTAINER_bloomfilter_test (bloom, &phash)))
1326 GNUNET_STATISTICS_update (GDS_stats,
1328 ("# Peers excluded from routing due to Bloomfilter"),
1330 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1331 "Excluded peer `%s' due to BF match in random routing for %s\n",
1332 GNUNET_i2s (&pos->id), GNUNET_h2s (key));
1334 continue; /* Ignore bloomfiltered peers */
1340 if (0 == count) /* No peers to select from! */
1342 GNUNET_STATISTICS_update (GDS_stats,
1343 gettext_noop ("# Peer selection failed"), 1,
1347 /* Now actually choose a peer */
1348 selected = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, count);
1350 for (bc = 0; bc <= closest_bucket; bc++)
1352 for (pos = k_buckets[bc].head; ((pos != NULL) && (count < bucket_size)); pos = pos->next)
1354 GNUNET_CRYPTO_hash (&pos->id,
1355 sizeof (struct GNUNET_PeerIdentity),
1357 if ((bloom != NULL) &&
1359 GNUNET_CONTAINER_bloomfilter_test (bloom, &phash)))
1361 continue; /* Ignore bloomfiltered peers */
1363 if (0 == selected--)
1373 * Compute the set of peers that the given request should be
1376 * @param key routing key
1377 * @param bloom bloom filter excluding peers as targets, all selected
1378 * peers will be added to the bloom filter
1379 * @param hop_count number of hops the request has traversed so far
1380 * @param target_replication desired number of replicas
1381 * @param targets where to store an array of target peers (to be
1382 * free'd by the caller)
1383 * @return number of peers returned in 'targets'.
1386 get_target_peers (const struct GNUNET_HashCode *key,
1387 struct GNUNET_CONTAINER_BloomFilter *bloom,
1388 uint32_t hop_count, uint32_t target_replication,
1389 struct PeerInfo ***targets)
1393 struct PeerInfo **rtargets;
1394 struct PeerInfo *nxt;
1395 struct GNUNET_HashCode nhash;
1397 GNUNET_assert (NULL != bloom);
1398 ret = get_forward_count (hop_count, target_replication);
1404 rtargets = GNUNET_malloc (sizeof (struct PeerInfo *) * ret);
1405 for (off = 0; off < ret; off++)
1407 nxt = select_peer (key, bloom, hop_count);
1410 rtargets[off] = nxt;
1411 GNUNET_CRYPTO_hash (&nxt->id,
1412 sizeof (struct GNUNET_PeerIdentity),
1414 GNUNET_break (GNUNET_NO ==
1415 GNUNET_CONTAINER_bloomfilter_test (bloom,
1417 GNUNET_CONTAINER_bloomfilter_add (bloom, &nhash);
1419 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1420 "Selected %u/%u peers at hop %u for %s (target was %u)\n",
1422 GNUNET_CONTAINER_multipeermap_size (all_connected_peers),
1423 (unsigned int) hop_count,
1428 GNUNET_free (rtargets);
1432 *targets = rtargets;
1433 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1434 "Forwarding query `%s' to %u peers (goal was %u peers)\n",
1443 * Perform a PUT operation. Forwards the given request to other
1444 * peers. Does not store the data locally. Does not give the
1445 * data to local clients. May do nothing if this is the only
1446 * peer in the network (or if we are the closest peer in the
1449 * @param type type of the block
1450 * @param options routing options
1451 * @param desired_replication_level desired replication count
1452 * @param expiration_time when does the content expire
1453 * @param hop_count how many hops has this message traversed so far
1454 * @param bf Bloom filter of peers this PUT has already traversed
1455 * @param key key for the content
1456 * @param put_path_length number of entries in @a put_path
1457 * @param put_path peers this request has traversed so far (if tracked)
1458 * @param data payload to store
1459 * @param data_size number of bytes in @a data
1460 * @return #GNUNET_OK if the request was forwarded, #GNUNET_NO if not
1463 GDS_NEIGHBOURS_handle_put (enum GNUNET_BLOCK_Type type,
1464 enum GNUNET_DHT_RouteOption options,
1465 uint32_t desired_replication_level,
1466 struct GNUNET_TIME_Absolute expiration_time,
1468 struct GNUNET_CONTAINER_BloomFilter *bf,
1469 const struct GNUNET_HashCode *key,
1470 unsigned int put_path_length,
1471 struct GNUNET_PeerIdentity *put_path,
1472 const void *data, size_t data_size)
1474 unsigned int target_count;
1476 struct PeerInfo **targets;
1477 struct PeerInfo *target;
1478 struct P2PPendingMessage *pending;
1480 struct PeerPutMessage *ppm;
1481 struct GNUNET_PeerIdentity *pp;
1482 struct GNUNET_HashCode thash;
1483 unsigned int skip_count;
1485 GNUNET_assert (NULL != bf);
1486 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1487 "Adding myself (%s) to PUT bloomfilter for %s\n",
1488 GNUNET_i2s (&my_identity),
1490 GNUNET_CONTAINER_bloomfilter_add (bf, &my_identity_hash);
1491 GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# PUT requests routed"),
1494 get_target_peers (key, bf, hop_count, desired_replication_level,
1496 if (0 == target_count)
1498 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1499 "Routing PUT for %s terminates after %u hops at %s\n",
1500 GNUNET_h2s (key), (unsigned int) hop_count,
1501 GNUNET_i2s (&my_identity));
1505 put_path_length * sizeof (struct GNUNET_PeerIdentity) + data_size +
1506 sizeof (struct PeerPutMessage);
1507 if (msize >= GNUNET_CONSTANTS_MAX_ENCRYPTED_MESSAGE_SIZE)
1509 put_path_length = 0;
1510 msize = data_size + sizeof (struct PeerPutMessage);
1512 if (msize >= GNUNET_CONSTANTS_MAX_ENCRYPTED_MESSAGE_SIZE)
1515 GNUNET_free (targets);
1518 GNUNET_STATISTICS_update (GDS_stats,
1520 ("# PUT messages queued for transmission"),
1521 target_count, GNUNET_NO);
1523 for (i = 0; i < target_count; i++)
1525 target = targets[i];
1526 if (target->pending_count >= MAXIMUM_PENDING_PER_PEER)
1529 GNUNET_STATISTICS_update (GDS_stats,
1530 gettext_noop ("# P2P messages dropped due to full queue"),
1535 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1536 "Routing PUT for %s after %u hops to %s\n",
1538 (unsigned int) hop_count,
1539 GNUNET_i2s (&target->id));
1540 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1541 pending->importance = 0; /* FIXME */
1542 pending->timeout = expiration_time;
1543 ppm = (struct PeerPutMessage *) &pending[1];
1544 pending->msg = &ppm->header;
1545 ppm->header.size = htons (msize);
1546 ppm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_PUT);
1547 ppm->options = htonl (options);
1548 ppm->type = htonl (type);
1549 ppm->hop_count = htonl (hop_count + 1);
1550 ppm->desired_replication_level = htonl (desired_replication_level);
1551 ppm->put_path_length = htonl (put_path_length);
1552 ppm->expiration_time = GNUNET_TIME_absolute_hton (expiration_time);
1553 GNUNET_CRYPTO_hash (&target->id,
1554 sizeof (struct GNUNET_PeerIdentity),
1556 GNUNET_break (GNUNET_YES ==
1557 GNUNET_CONTAINER_bloomfilter_test (bf,
1559 GNUNET_assert (GNUNET_OK ==
1560 GNUNET_CONTAINER_bloomfilter_get_raw_data (bf,
1564 pp = (struct GNUNET_PeerIdentity *) &ppm[1];
1565 memcpy (pp, put_path,
1566 sizeof (struct GNUNET_PeerIdentity) * put_path_length);
1567 memcpy (&pp[put_path_length],
1570 GNUNET_CONTAINER_DLL_insert_tail (target->head,
1573 target->pending_count++;
1574 if (pending == target->head)
1575 process_peer_queue (target);
1577 GNUNET_free (targets);
1578 return (skip_count < target_count) ? GNUNET_OK : GNUNET_NO;
1583 * Perform a GET operation. Forwards the given request to other
1584 * peers. Does not lookup the key locally. May do nothing if this is
1585 * the only peer in the network (or if we are the closest peer in the
1588 * @param type type of the block
1589 * @param options routing options
1590 * @param desired_replication_level desired replication count
1591 * @param hop_count how many hops did this request traverse so far?
1592 * @param key key for the content
1593 * @param xquery extended query
1594 * @param xquery_size number of bytes in @a xquery
1595 * @param reply_bf bloomfilter to filter duplicates
1596 * @param reply_bf_mutator mutator for @a reply_bf
1597 * @param peer_bf filter for peers not to select (again)
1598 * @return #GNUNET_OK if the request was forwarded, #GNUNET_NO if not
1601 GDS_NEIGHBOURS_handle_get (enum GNUNET_BLOCK_Type type,
1602 enum GNUNET_DHT_RouteOption options,
1603 uint32_t desired_replication_level,
1604 uint32_t hop_count, const struct GNUNET_HashCode * key,
1605 const void *xquery, size_t xquery_size,
1606 const struct GNUNET_CONTAINER_BloomFilter *reply_bf,
1607 uint32_t reply_bf_mutator,
1608 struct GNUNET_CONTAINER_BloomFilter *peer_bf)
1610 unsigned int target_count;
1612 struct PeerInfo **targets;
1613 struct PeerInfo *target;
1614 struct P2PPendingMessage *pending;
1616 struct PeerGetMessage *pgm;
1618 size_t reply_bf_size;
1619 struct GNUNET_HashCode thash;
1620 unsigned int skip_count;
1622 GNUNET_assert (NULL != peer_bf);
1623 GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# GET requests routed"),
1626 get_target_peers (key, peer_bf, hop_count, desired_replication_level,
1628 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1629 "Adding myself (%s) to GET bloomfilter for %s\n",
1630 GNUNET_i2s (&my_identity),
1632 GNUNET_CONTAINER_bloomfilter_add (peer_bf,
1634 if (0 == target_count)
1636 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1637 "Routing GET for %s terminates after %u hops at %s\n",
1638 GNUNET_h2s (key), (unsigned int) hop_count,
1639 GNUNET_i2s (&my_identity));
1642 reply_bf_size = GNUNET_CONTAINER_bloomfilter_get_size (reply_bf);
1643 msize = xquery_size + sizeof (struct PeerGetMessage) + reply_bf_size;
1644 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1647 GNUNET_free (targets);
1650 GNUNET_STATISTICS_update (GDS_stats,
1652 ("# GET messages queued for transmission"),
1653 target_count, GNUNET_NO);
1654 /* forward request */
1656 for (i = 0; i < target_count; i++)
1658 target = targets[i];
1659 if (target->pending_count >= MAXIMUM_PENDING_PER_PEER)
1662 GNUNET_STATISTICS_update (GDS_stats,
1663 gettext_noop ("# P2P messages dropped due to full queue"),
1668 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1669 "Routing GET for %s after %u hops to %s\n",
1671 (unsigned int) hop_count,
1672 GNUNET_i2s (&target->id));
1673 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1674 pending->importance = 0; /* FIXME */
1675 pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
1676 pgm = (struct PeerGetMessage *) &pending[1];
1677 pending->msg = &pgm->header;
1678 pgm->header.size = htons (msize);
1679 pgm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_GET);
1680 pgm->options = htonl (options);
1681 pgm->type = htonl (type);
1682 pgm->hop_count = htonl (hop_count + 1);
1683 pgm->desired_replication_level = htonl (desired_replication_level);
1684 pgm->xquery_size = htonl (xquery_size);
1685 pgm->bf_mutator = reply_bf_mutator;
1686 GNUNET_CRYPTO_hash (&target->id,
1687 sizeof (struct GNUNET_PeerIdentity),
1689 GNUNET_break (GNUNET_YES ==
1690 GNUNET_CONTAINER_bloomfilter_test (peer_bf,
1692 GNUNET_assert (GNUNET_OK ==
1693 GNUNET_CONTAINER_bloomfilter_get_raw_data (peer_bf,
1697 xq = (char *) &pgm[1];
1698 memcpy (xq, xquery, xquery_size);
1699 if (NULL != reply_bf)
1700 GNUNET_assert (GNUNET_OK ==
1701 GNUNET_CONTAINER_bloomfilter_get_raw_data (reply_bf,
1705 GNUNET_CONTAINER_DLL_insert_tail (target->head,
1708 target->pending_count++;
1709 if (pending == target->head)
1710 process_peer_queue (target);
1712 GNUNET_free (targets);
1713 return (skip_count < target_count) ? GNUNET_OK : GNUNET_NO;
1718 * Handle a reply (route to origin). Only forwards the reply back to
1719 * the given peer. Does not do local caching or forwarding to local
1722 * @param target neighbour that should receive the block (if still connected)
1723 * @param type type of the block
1724 * @param expiration_time when does the content expire
1725 * @param key key for the content
1726 * @param put_path_length number of entries in @a put_path
1727 * @param put_path peers the original PUT traversed (if tracked)
1728 * @param get_path_length number of entries in @a get_path
1729 * @param get_path peers this reply has traversed so far (if tracked)
1730 * @param data payload of the reply
1731 * @param data_size number of bytes in @a data
1734 GDS_NEIGHBOURS_handle_reply (const struct GNUNET_PeerIdentity *target,
1735 enum GNUNET_BLOCK_Type type,
1736 struct GNUNET_TIME_Absolute expiration_time,
1737 const struct GNUNET_HashCode *key,
1738 unsigned int put_path_length,
1739 const struct GNUNET_PeerIdentity *put_path,
1740 unsigned int get_path_length,
1741 const struct GNUNET_PeerIdentity *get_path,
1745 struct PeerInfo *pi;
1746 struct P2PPendingMessage *pending;
1748 struct PeerResultMessage *prm;
1749 struct GNUNET_PeerIdentity *paths;
1752 data_size + sizeof (struct PeerResultMessage) + (get_path_length +
1754 sizeof (struct GNUNET_PeerIdentity);
1755 if ((msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE) ||
1757 GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
1759 GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
1760 (data_size > GNUNET_SERVER_MAX_MESSAGE_SIZE))
1765 pi = GNUNET_CONTAINER_multipeermap_get (all_connected_peers,
1769 /* peer disconnected in the meantime, drop reply */
1770 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1771 "No matching peer for reply for key %s\n",
1775 if (pi->pending_count >= MAXIMUM_PENDING_PER_PEER)
1778 GNUNET_STATISTICS_update (GDS_stats,
1779 gettext_noop ("# P2P messages dropped due to full queue"),
1782 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1783 "Peer queue full, ignoring reply for key %s\n",
1788 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1789 "Forwarding reply for key %s to peer %s\n",
1791 GNUNET_i2s (target));
1792 GNUNET_STATISTICS_update (GDS_stats,
1794 ("# RESULT messages queued for transmission"), 1,
1796 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1797 pending->importance = 0; /* FIXME */
1798 pending->timeout = expiration_time;
1799 prm = (struct PeerResultMessage *) &pending[1];
1800 pending->msg = &prm->header;
1801 prm->header.size = htons (msize);
1802 prm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT);
1803 prm->type = htonl (type);
1804 prm->put_path_length = htonl (put_path_length);
1805 prm->get_path_length = htonl (get_path_length);
1806 prm->expiration_time = GNUNET_TIME_absolute_hton (expiration_time);
1808 paths = (struct GNUNET_PeerIdentity *) &prm[1];
1811 put_path_length * sizeof (struct GNUNET_PeerIdentity));
1812 memcpy (&paths[put_path_length],
1814 get_path_length * sizeof (struct GNUNET_PeerIdentity));
1815 memcpy (&paths[put_path_length + get_path_length],
1818 GNUNET_CONTAINER_DLL_insert (pi->head,
1821 pi->pending_count++;
1822 process_peer_queue (pi);
1827 * To be called on core init/fail.
1829 * @param cls service closure
1830 * @param identity the public identity of this peer
1833 core_init (void *cls,
1834 const struct GNUNET_PeerIdentity *identity)
1836 GNUNET_log (GNUNET_ERROR_TYPE_INFO,
1837 "CORE called, I am %s\n",
1838 GNUNET_i2s (identity));
1839 my_identity = *identity;
1840 GNUNET_CRYPTO_hash (identity,
1841 sizeof (struct GNUNET_PeerIdentity),
1843 GDS_CLIENTS_init ();
1848 * Core handler for p2p put requests.
1850 * @param cls closure
1851 * @param peer sender of the request
1852 * @param message message
1853 * @param peer peer identity this notification is about
1854 * @return #GNUNET_OK to keep the connection open,
1855 * #GNUNET_SYSERR to close it (signal serious error)
1858 handle_dht_p2p_put (void *cls,
1859 const struct GNUNET_PeerIdentity *peer,
1860 const struct GNUNET_MessageHeader *message)
1862 const struct PeerPutMessage *put;
1863 const struct GNUNET_PeerIdentity *put_path;
1864 const void *payload;
1867 size_t payload_size;
1868 enum GNUNET_DHT_RouteOption options;
1869 struct GNUNET_CONTAINER_BloomFilter *bf;
1870 struct GNUNET_HashCode test_key;
1871 struct GNUNET_HashCode phash;
1874 msize = ntohs (message->size);
1875 if (msize < sizeof (struct PeerPutMessage))
1877 GNUNET_break_op (0);
1880 put = (const struct PeerPutMessage *) message;
1881 putlen = ntohl (put->put_path_length);
1883 sizeof (struct PeerPutMessage) +
1884 putlen * sizeof (struct GNUNET_PeerIdentity)) ||
1886 GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
1888 GNUNET_break_op (0);
1891 GNUNET_STATISTICS_update (GDS_stats,
1892 gettext_noop ("# P2P PUT requests received"),
1895 GNUNET_STATISTICS_update (GDS_stats,
1896 gettext_noop ("# P2P PUT bytes received"),
1899 put_path = (const struct GNUNET_PeerIdentity *) &put[1];
1900 payload = &put_path[putlen];
1901 options = ntohl (put->options);
1903 msize - (sizeof (struct PeerPutMessage) +
1904 putlen * sizeof (struct GNUNET_PeerIdentity));
1906 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "PUT for `%s' from %s\n",
1907 GNUNET_h2s (&put->key), GNUNET_i2s (peer));
1908 GNUNET_CRYPTO_hash (peer, sizeof (struct GNUNET_PeerIdentity), &phash);
1909 if (GNUNET_YES == log_route_details_stderr)
1913 tmp = GNUNET_strdup (GNUNET_i2s (&my_identity));
1914 LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG,
1915 "R5N PUT %s: %s->%s (%u, %u=>%u)\n",
1916 GNUNET_h2s (&put->key),
1919 ntohl(put->hop_count),
1920 GNUNET_CRYPTO_hash_matching_bits (&phash,
1922 GNUNET_CRYPTO_hash_matching_bits (&my_identity_hash,
1927 switch (GNUNET_BLOCK_get_key
1928 (GDS_block_context, ntohl (put->type), payload, payload_size,
1932 if (0 != memcmp (&test_key, &put->key, sizeof (struct GNUNET_HashCode)))
1934 char *put_s = GNUNET_strdup (GNUNET_h2s_full (&put->key));
1936 GNUNET_break_op (0);
1937 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1938 "PUT with key `%s' for block with key %s\n",
1939 put_s, GNUNET_h2s_full (&test_key));
1940 GNUNET_free (put_s);
1945 GNUNET_break_op (0);
1948 /* cannot verify, good luck */
1951 if (ntohl (put->type) == GNUNET_BLOCK_TYPE_REGEX) /* FIXME: do for all tpyes */
1953 switch (GNUNET_BLOCK_evaluate (GDS_block_context,
1955 GNUNET_BLOCK_EO_NONE,
1957 NULL, 0, /* bloom filer */
1958 NULL, 0, /* xquery */
1959 payload, payload_size))
1961 case GNUNET_BLOCK_EVALUATION_OK_MORE:
1962 case GNUNET_BLOCK_EVALUATION_OK_LAST:
1965 case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE:
1966 case GNUNET_BLOCK_EVALUATION_RESULT_INVALID:
1967 case GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT:
1968 case GNUNET_BLOCK_EVALUATION_REQUEST_VALID:
1969 case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID:
1970 case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED:
1972 GNUNET_break_op (0);
1977 bf = GNUNET_CONTAINER_bloomfilter_init (put->bloomfilter,
1979 GNUNET_CONSTANTS_BLOOMFILTER_K);
1980 GNUNET_break_op (GNUNET_YES ==
1981 GNUNET_CONTAINER_bloomfilter_test (bf, &phash));
1983 struct GNUNET_PeerIdentity pp[putlen + 1];
1985 /* extend 'put path' by sender */
1986 if (0 != (options & GNUNET_DHT_RO_RECORD_ROUTE))
1988 memcpy (pp, put_path, putlen * sizeof (struct GNUNET_PeerIdentity));
1995 /* give to local clients */
1996 GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (put->expiration_time),
1997 &put->key, 0, NULL, putlen, pp, ntohl (put->type),
1998 payload_size, payload);
2000 if ((0 != (options & GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE)) ||
2001 (am_closest_peer (&put->key, bf)))
2002 GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh
2003 (put->expiration_time), &put->key, putlen, pp,
2004 ntohl (put->type), payload_size, payload);
2005 /* route to other peers */
2006 forwarded = GDS_NEIGHBOURS_handle_put (ntohl (put->type), options,
2007 ntohl (put->desired_replication_level),
2008 GNUNET_TIME_absolute_ntoh (put->expiration_time),
2009 ntohl (put->hop_count), bf,
2015 /* notify monitoring clients */
2016 GDS_CLIENTS_process_put (options
2017 | ( (GNUNET_OK == forwarded)
2018 ? GNUNET_DHT_RO_LAST_HOP
2021 ntohl (put->hop_count),
2022 ntohl (put->desired_replication_level),
2024 GNUNET_TIME_absolute_ntoh (put->expiration_time),
2029 GNUNET_CONTAINER_bloomfilter_free (bf);
2035 * We have received a FIND PEER request. Send matching
2038 * @param sender sender of the FIND PEER request
2039 * @param key peers close to this key are desired
2040 * @param bf peers matching this bf are excluded
2041 * @param bf_mutator mutator for bf
2044 handle_find_peer (const struct GNUNET_PeerIdentity *sender,
2045 const struct GNUNET_HashCode * key,
2046 struct GNUNET_CONTAINER_BloomFilter *bf, uint32_t bf_mutator)
2049 struct PeerBucket *bucket;
2050 struct PeerInfo *peer;
2051 unsigned int choice;
2052 struct GNUNET_HashCode phash;
2053 struct GNUNET_HashCode mhash;
2054 const struct GNUNET_HELLO_Message *hello;
2056 /* first, check about our own HELLO */
2057 if (NULL != GDS_my_hello)
2059 GNUNET_BLOCK_mingle_hash (&my_identity_hash, bf_mutator, &mhash);
2061 (GNUNET_YES != GNUNET_CONTAINER_bloomfilter_test (bf, &mhash)))
2063 GDS_NEIGHBOURS_handle_reply (sender, GNUNET_BLOCK_TYPE_DHT_HELLO,
2064 GNUNET_TIME_relative_to_absolute
2066 key, 0, NULL, 0, NULL, GDS_my_hello,
2067 GNUNET_HELLO_size ((const struct
2068 GNUNET_HELLO_Message *)
2073 GNUNET_STATISTICS_update (GDS_stats,
2075 ("# FIND PEER requests ignored due to Bloomfilter"),
2081 GNUNET_STATISTICS_update (GDS_stats,
2083 ("# FIND PEER requests ignored due to lack of HELLO"),
2087 /* then, also consider sending a random HELLO from the closest bucket */
2088 if (0 == memcmp (&my_identity_hash, key, sizeof (struct GNUNET_HashCode)))
2089 bucket_idx = closest_bucket;
2091 bucket_idx = GNUNET_MIN (closest_bucket, find_bucket (key));
2092 if (bucket_idx == GNUNET_SYSERR)
2094 bucket = &k_buckets[bucket_idx];
2095 if (bucket->peers_size == 0)
2098 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, bucket->peers_size);
2099 peer = bucket->head;
2102 GNUNET_assert (NULL != peer);
2106 choice = bucket->peers_size;
2111 return; /* no non-masked peer available */
2113 peer = bucket->head;
2114 GNUNET_CRYPTO_hash (&peer->id,
2115 sizeof (struct GNUNET_PeerIdentity),
2117 GNUNET_BLOCK_mingle_hash (&phash,
2120 hello = GDS_HELLO_get (&peer->id);
2122 while ((hello == NULL) ||
2123 (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bf, &mhash)));
2124 GDS_NEIGHBOURS_handle_reply (sender, GNUNET_BLOCK_TYPE_DHT_HELLO,
2125 GNUNET_TIME_relative_to_absolute
2126 (GNUNET_CONSTANTS_HELLO_ADDRESS_EXPIRATION), key,
2127 0, NULL, 0, NULL, hello,
2128 GNUNET_HELLO_size (hello));
2133 * Core handler for p2p get requests.
2135 * @param cls closure
2136 * @param peer sender of the request
2137 * @param message message
2138 * @return #GNUNET_OK to keep the connection open,
2139 * #GNUNET_SYSERR to close it (signal serious error)
2142 handle_dht_p2p_get (void *cls,
2143 const struct GNUNET_PeerIdentity *peer,
2144 const struct GNUNET_MessageHeader *message)
2146 struct PeerGetMessage *get;
2147 uint32_t xquery_size;
2148 size_t reply_bf_size;
2150 enum GNUNET_BLOCK_Type type;
2151 enum GNUNET_DHT_RouteOption options;
2152 enum GNUNET_BLOCK_EvaluationResult eval;
2153 struct GNUNET_CONTAINER_BloomFilter *reply_bf;
2154 struct GNUNET_CONTAINER_BloomFilter *peer_bf;
2156 struct GNUNET_HashCode phash;
2162 sizeof (struct GNUNET_PeerIdentity)));
2163 /* parse and validate message */
2164 msize = ntohs (message->size);
2165 if (msize < sizeof (struct PeerGetMessage))
2167 GNUNET_break_op (0);
2170 get = (struct PeerGetMessage *) message;
2171 xquery_size = ntohl (get->xquery_size);
2172 if (msize < sizeof (struct PeerGetMessage) + xquery_size)
2174 GNUNET_break_op (0);
2177 reply_bf_size = msize - (sizeof (struct PeerGetMessage) + xquery_size);
2178 type = ntohl (get->type);
2179 options = ntohl (get->options);
2180 xquery = (const char *) &get[1];
2182 GNUNET_STATISTICS_update (GDS_stats,
2183 gettext_noop ("# P2P GET requests received"), 1,
2185 GNUNET_STATISTICS_update (GDS_stats,
2186 gettext_noop ("# P2P GET bytes received"), msize,
2188 GNUNET_CRYPTO_hash (peer,
2189 sizeof (struct GNUNET_PeerIdentity),
2191 if (GNUNET_YES == log_route_details_stderr)
2195 tmp = GNUNET_strdup (GNUNET_i2s (&my_identity));
2196 LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG,
2197 "R5N GET %s: %s->%s (%u, %u=>%u) xq: %.*s\n",
2198 GNUNET_h2s (&get->key), GNUNET_i2s (peer), tmp,
2199 ntohl(get->hop_count),
2200 GNUNET_CRYPTO_hash_matching_bits (&phash, &get->key),
2201 GNUNET_CRYPTO_hash_matching_bits (&my_identity_hash, &get->key),
2202 ntohl(get->xquery_size), xquery);
2206 if (reply_bf_size > 0)
2208 GNUNET_CONTAINER_bloomfilter_init (&xquery[xquery_size], reply_bf_size,
2209 GNUNET_CONSTANTS_BLOOMFILTER_K);
2211 GNUNET_BLOCK_evaluate (GDS_block_context,
2213 GNUNET_BLOCK_EO_NONE,
2221 if (eval != GNUNET_BLOCK_EVALUATION_REQUEST_VALID)
2223 /* request invalid or block type not supported */
2224 GNUNET_break_op (eval == GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED);
2225 if (NULL != reply_bf)
2226 GNUNET_CONTAINER_bloomfilter_free (reply_bf);
2230 GNUNET_CONTAINER_bloomfilter_init (get->bloomfilter, DHT_BLOOM_SIZE,
2231 GNUNET_CONSTANTS_BLOOMFILTER_K);
2232 GNUNET_break_op (GNUNET_YES ==
2233 GNUNET_CONTAINER_bloomfilter_test (peer_bf,
2235 /* remember request for routing replies */
2236 GDS_ROUTING_add (peer, type, options, &get->key, xquery, xquery_size,
2237 reply_bf, get->bf_mutator);
2238 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2239 "GET for %s at %s after %u hops\n",
2240 GNUNET_h2s (&get->key),
2241 GNUNET_i2s (&my_identity),
2242 (unsigned int) ntohl (get->hop_count));
2243 /* local lookup (this may update the reply_bf) */
2244 if ((0 != (options & GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE)) ||
2245 (am_closest_peer (&get->key, peer_bf)))
2247 if ((0 != (options & GNUNET_DHT_RO_FIND_PEER)))
2249 GNUNET_STATISTICS_update (GDS_stats,
2251 ("# P2P FIND PEER requests processed"), 1,
2253 handle_find_peer (peer, &get->key, reply_bf, get->bf_mutator);
2258 GDS_DATACACHE_handle_get (&get->key, type, xquery, xquery_size,
2259 &reply_bf, get->bf_mutator);
2264 GNUNET_STATISTICS_update (GDS_stats,
2265 gettext_noop ("# P2P GET requests ONLY routed"),
2269 /* P2P forwarding */
2270 forwarded = GNUNET_NO;
2271 if (eval != GNUNET_BLOCK_EVALUATION_OK_LAST)
2272 forwarded = GDS_NEIGHBOURS_handle_get (type, options,
2273 ntohl (get->desired_replication_level),
2274 ntohl (get->hop_count),
2279 get->bf_mutator, peer_bf);
2280 GDS_CLIENTS_process_get (options
2281 | (GNUNET_OK == forwarded)
2282 ? GNUNET_DHT_RO_LAST_HOP : 0,
2284 ntohl (get->hop_count),
2285 ntohl (get->desired_replication_level),
2291 if (NULL != reply_bf)
2292 GNUNET_CONTAINER_bloomfilter_free (reply_bf);
2293 GNUNET_CONTAINER_bloomfilter_free (peer_bf);
2299 * Core handler for p2p result messages.
2301 * @param cls closure
2302 * @param message message
2303 * @param peer peer identity this notification is about
2304 * @return #GNUNET_YES (do not cut p2p connection)
2307 handle_dht_p2p_result (void *cls,
2308 const struct GNUNET_PeerIdentity *peer,
2309 const struct GNUNET_MessageHeader *message)
2311 const struct PeerResultMessage *prm;
2312 const struct GNUNET_PeerIdentity *put_path;
2313 const struct GNUNET_PeerIdentity *get_path;
2315 uint32_t get_path_length;
2316 uint32_t put_path_length;
2319 enum GNUNET_BLOCK_Type type;
2321 /* parse and validate message */
2322 msize = ntohs (message->size);
2323 if (msize < sizeof (struct PeerResultMessage))
2325 GNUNET_break_op (0);
2328 prm = (struct PeerResultMessage *) message;
2329 put_path_length = ntohl (prm->put_path_length);
2330 get_path_length = ntohl (prm->get_path_length);
2332 sizeof (struct PeerResultMessage) + (get_path_length +
2334 sizeof (struct GNUNET_PeerIdentity)) ||
2336 GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
2338 GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
2340 GNUNET_break_op (0);
2343 put_path = (const struct GNUNET_PeerIdentity *) &prm[1];
2344 get_path = &put_path[put_path_length];
2345 type = ntohl (prm->type);
2346 data = (const void *) &get_path[get_path_length];
2348 msize - (sizeof (struct PeerResultMessage) +
2350 put_path_length) * sizeof (struct GNUNET_PeerIdentity));
2351 GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P RESULTS received"),
2353 GNUNET_STATISTICS_update (GDS_stats,
2354 gettext_noop ("# P2P RESULT bytes received"),
2356 if (GNUNET_YES == log_route_details_stderr)
2360 tmp = GNUNET_strdup (GNUNET_i2s (&my_identity));
2361 LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG,
2362 "R5N RESULT %s: %s->%s (%u)\n",
2363 GNUNET_h2s (&prm->key),
2366 get_path_length + 1);
2369 /* if we got a HELLO, consider it for our own routing table */
2370 if (GNUNET_BLOCK_TYPE_DHT_HELLO == type)
2372 const struct GNUNET_MessageHeader *h;
2373 struct GNUNET_PeerIdentity pid;
2375 /* Should be a HELLO, validate and consider using it! */
2376 if (data_size < sizeof (struct GNUNET_MessageHeader))
2378 GNUNET_break_op (0);
2382 if (data_size != ntohs (h->size))
2384 GNUNET_break_op (0);
2388 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) h,
2391 GNUNET_break_op (0);
2394 if ( (GNUNET_YES != disable_try_connect) &&
2395 (0 != memcmp (&my_identity,
2397 sizeof (struct GNUNET_PeerIdentity))) )
2402 /* append 'peer' to 'get_path' */
2404 struct GNUNET_PeerIdentity xget_path[get_path_length + 1];
2408 get_path_length * sizeof (struct GNUNET_PeerIdentity));
2409 xget_path[get_path_length] = *peer;
2412 /* forward to local clients */
2413 GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (prm->expiration_time),
2422 GDS_CLIENTS_process_get_resp (type,
2425 put_path, put_path_length,
2426 GNUNET_TIME_absolute_ntoh (prm->expiration_time),
2430 if (GNUNET_YES == cache_results)
2432 struct GNUNET_PeerIdentity xput_path[get_path_length + 1 + put_path_length];
2434 memcpy (xput_path, put_path, put_path_length * sizeof (struct GNUNET_PeerIdentity));
2435 memcpy (&xput_path[put_path_length],
2437 get_path_length * sizeof (struct GNUNET_PeerIdentity));
2439 GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (prm->expiration_time),
2441 get_path_length + put_path_length,
2447 /* forward to other peers */
2448 GDS_ROUTING_process (type,
2449 GNUNET_TIME_absolute_ntoh (prm->expiration_time),
2464 * Initialize neighbours subsystem.
2466 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
2469 GDS_NEIGHBOURS_init ()
2471 static struct GNUNET_CORE_MessageHandler core_handlers[] = {
2472 {&handle_dht_p2p_get, GNUNET_MESSAGE_TYPE_DHT_P2P_GET, 0},
2473 {&handle_dht_p2p_put, GNUNET_MESSAGE_TYPE_DHT_P2P_PUT, 0},
2474 {&handle_dht_p2p_result, GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT, 0},
2477 unsigned long long temp_config_num;
2480 = GNUNET_CONFIGURATION_get_value_yesno (GDS_cfg, "DHT", "DISABLE_TRY_CONNECT");
2482 GNUNET_CONFIGURATION_get_value_number (GDS_cfg, "DHT", "bucket_size",
2484 bucket_size = (unsigned int) temp_config_num;
2486 = GNUNET_CONFIGURATION_get_value_yesno (GDS_cfg, "DHT", "CACHE_RESULTS");
2488 log_route_details_stderr =
2489 (NULL != getenv("GNUNET_DHT_ROUTE_DEBUG")) ? GNUNET_YES : GNUNET_NO;
2490 ats_ch = GNUNET_ATS_connectivity_init (GDS_cfg);
2492 GNUNET_CORE_connect (GDS_cfg, NULL,
2494 &handle_core_connect,
2495 &handle_core_disconnect,
2499 if (core_api == NULL)
2500 return GNUNET_SYSERR;
2501 all_connected_peers = GNUNET_CONTAINER_multipeermap_create (256,
2503 all_desired_peers = GNUNET_CONTAINER_multipeermap_create (256,
2510 * Shutdown neighbours subsystem.
2513 GDS_NEIGHBOURS_done ()
2515 if (NULL == core_api)
2517 GNUNET_CORE_disconnect (core_api);
2519 GNUNET_assert (0 == GNUNET_CONTAINER_multipeermap_size (all_connected_peers));
2520 GNUNET_CONTAINER_multipeermap_destroy (all_connected_peers);
2521 all_connected_peers = NULL;
2522 GNUNET_CONTAINER_multipeermap_iterate (all_desired_peers,
2525 GNUNET_CONTAINER_multipeermap_destroy (all_desired_peers);
2526 all_desired_peers = NULL;
2527 GNUNET_ATS_connectivity_done (ats_ch);
2529 GNUNET_assert (NULL == find_peer_task);
2534 * Get the ID of the local node.
2536 * @return identity of the local node
2538 struct GNUNET_PeerIdentity *
2539 GDS_NEIGHBOURS_get_id ()
2541 return &my_identity;
2545 /* end of gnunet-service-dht_neighbours.c */