2 This file is part of GNUnet.
3 (C) 2009-2014 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.
10 GNUnet is distributed in the hope that it will be useful, but
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,
18 Boston, MA 02111-1307, USA.
22 * @file dht/gnunet-service-xdht_neighbours.c
23 * @brief GNUnet DHT service's finger and friend table management code
24 * @author Supriti Singh
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_ats_service.h"
34 #include "gnunet_core_service.h"
35 #include "gnunet_datacache_lib.h"
36 #include "gnunet_transport_service.h"
37 #include "gnunet_dht_service.h"
38 #include "gnunet_statistics_service.h"
39 #include "gnunet-service-xdht.h"
40 #include "gnunet-service-xdht_clients.h"
41 #include "gnunet-service-xdht_datacache.h"
42 #include "gnunet-service-xdht_neighbours.h"
43 #include "gnunet-service-xdht_routing.h"
49 * 1. In X-Vine paper, there is no policy defined for replicating the data to
50 * recover in case of peer failure. We can do it in Chord way. In R5N, the key
51 * is hashed and then data is stored according to the key value generated after
53 * 2. We will keep an entry in routing table even if its a friend for the moment.
54 * Because I am not sure if there is a case where it will not work.
55 * Trail id we can keep but actually there is no trail.
61 * 1. check for memory leaks in all the functions, in all the functions
62 * you should check that if you malloc a variable you should free it also.
63 * 2. make sure you have gnunet_assert for all target friends
64 * 3. pay attention to GNUNET_ntohll and endianess
65 * 4. In trail setup, check that you are adding entry even if its a friend.
66 * same for trail setup and add_trail.
67 * 5. go through whole code
68 * 6. make sure make check passes for minimal things i.e. without congestion,
69 * trail threshold, without multiple trails.
70 * 7. write test cases for checking trail congestion, trail threshold, multiple
73 * 8. while going through the code write the comments for malicious peer.
74 * basic - drop packet, ignore message. Not going to check for behaviour
75 * where a peer changes the value as we handle that case everywhere. s
78 1. friend trails count in case it is finger, routing table trail
79 2. select_closest_peer in compare and update predecessor and successor,
85 * Maximum possible fingers (including predecessor) of a peer
87 #define MAX_FINGERS 65
90 * Maximum allowed number of pending messages per friend peer.
92 #define MAXIMUM_PENDING_PER_FRIEND 64
95 * How long to wait before sending another find finger trail request
97 #define DHT_FIND_FINGER_TRAIL_INTERVAL GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30)
100 * How long at most to wait for transmission of a request to a friend ?
102 #define GET_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 2)
105 * Duration for which I may remain congested.
106 * Note: Its a static value. In future, a peer may do some analysis and calculate
107 * congestion_timeout based on 'some' parameters.
109 #define CONGESTION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 2)
112 * Maximum number of trails allowed to go through a friend.
114 #define TRAILS_THROUGH_FRIEND_THRESHOLD 64
117 * Maximum number of trails stored per finger.
119 #define MAXIMUM_TRAILS_PER_FINGER 1
122 * Finger map index for predecessor entry in finger table.
124 #define PREDECESSOR_FINGER_ID 64
127 * Wrap around in peer identity circle.
129 #define PEER_IDENTITES_WRAP_AROUND pow(2, 64) - 1
132 * FIXME: Its use only at 3 places check if you can remove it.
133 * To check if a finger is predecessor or not.
135 enum GDS_NEIGHBOURS_finger_type
137 GDS_FINGER_TYPE_PREDECESSOR = 0,
138 GDS_FINGER_TYPE_NON_PREDECESSOR = 1
141 GNUNET_NETWORK_STRUCT_BEGIN
146 struct PeerPutMessage
149 * Type: #GNUNET_MESSAGE_TYPE_XDHT_P2P_PUT
151 struct GNUNET_MessageHeader header;
156 uint32_t options GNUNET_PACKED;
161 uint32_t block_type GNUNET_PACKED;
166 uint32_t hop_count GNUNET_PACKED;
169 * Replication level for this message
170 * In the current implementation, this value is not used.
172 uint32_t desired_replication_level GNUNET_PACKED;
175 * Length of the PUT path that follows (if tracked).
177 uint32_t put_path_length GNUNET_PACKED;
180 * Best known destination (could be my friend or finger) which should
181 * get this message next.
183 struct GNUNET_PeerIdentity best_known_destination;
186 * In case best_known_destination is a finger, then trail to reach
187 * to that finger. Else its default value is 0.
189 struct GNUNET_HashCode intermediate_trail_id;
192 * When does the content expire?
194 struct GNUNET_TIME_AbsoluteNBO expiration_time;
197 * The key to store the value under.
199 struct GNUNET_HashCode key GNUNET_PACKED;
201 /* put path (if tracked) */
210 struct PeerGetMessage
213 * Type: #GNUNET_MESSAGE_TYPE_XDHT_P2P_GET
215 struct GNUNET_MessageHeader header;
220 uint32_t options GNUNET_PACKED;
223 * Desired content type.
225 uint32_t block_type GNUNET_PACKED;
230 uint32_t hop_count GNUNET_PACKED;
233 * Desired replication level for this request.
234 * In the current implementation, this value is not used.
236 uint32_t desired_replication_level GNUNET_PACKED;
239 * Total number of peers in get path.
241 unsigned int get_path_length;
244 * Best known destination (could be my friend or finger) which should
245 * get this message next.
247 struct GNUNET_PeerIdentity best_known_destination;
250 * In case best_known_destination is a finger, then trail to reach
251 * to that finger. Else its default value is 0.
253 struct GNUNET_HashCode intermediate_trail_id;
256 * The key we are looking for.
258 struct GNUNET_HashCode key;
267 struct PeerGetResultMessage
270 * Type: #GNUNET_MESSAGE_TYPE_XDHT_P2P_GET_RESULT
272 struct GNUNET_MessageHeader header;
275 * The type for the data.
277 uint32_t type GNUNET_PACKED;
280 * Number of peers recorded in the outgoing path from source to the
281 * stored location of this message.
283 uint32_t put_path_length GNUNET_PACKED;
286 * Length of the GET path that follows (if tracked).
288 uint32_t get_path_length GNUNET_PACKED;
291 * Peer which queried for get and should get the result.
293 struct GNUNET_PeerIdentity querying_peer;
296 * When does the content expire?
298 struct GNUNET_TIME_Absolute expiration_time;
301 * The key of the corresponding GET request.
303 struct GNUNET_HashCode key;
305 /* put path (if tracked) */
307 /* get path (if tracked) */
314 * P2P Trail setup message
316 struct PeerTrailSetupMessage
319 * Type: #GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_SETUP
321 struct GNUNET_MessageHeader header;
324 * Is source_peer trying to setup the trail to a predecessor or any finger.
326 uint32_t is_predecessor;
329 * Peer closest to this value will be our finger.
331 uint64_t final_destination_finger_value;
334 * Source peer which wants to setup the trail to one of its finger.
336 struct GNUNET_PeerIdentity source_peer;
339 * Best known destination (could be my friend or finger) which should
340 * get this message next.
342 struct GNUNET_PeerIdentity best_known_destination;
345 * In case best_known_destination is a finger, then trail id of trail to
346 * reach to this finger.
348 struct GNUNET_HashCode intermediate_trail_id;
351 * Trail id for trail which we are trying to setup.
353 struct GNUNET_HashCode trail_id;
355 /* List of peers which are part of trail setup so far.
356 * Trail does NOT include source_peer and peer which will be closest to
357 * ultimate_destination_finger_value.
358 * struct GNUNET_PeerIdentity trail[]
363 * P2P Trail Setup Result message
365 struct PeerTrailSetupResultMessage
369 * Type: #GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_SETUP_RESULT
371 struct GNUNET_MessageHeader header;
374 * Finger to which we have found the path.
376 struct GNUNET_PeerIdentity finger_identity;
379 * Peer which started trail_setup to find trail to finger_identity
381 struct GNUNET_PeerIdentity querying_peer;
384 * Is the trail setup to querying_peer's predecessor or finger?
386 uint32_t is_predecessor;
389 * Value to which finger_identity is the closest peer.
391 uint64_t ulitmate_destination_finger_value;
394 * Identifier of the trail from querying peer to finger_identity, NOT
395 * including both endpoints.
397 struct GNUNET_HashCode trail_id;
399 /* List of peers which are part of the trail from querying peer to
400 * finger_identity, NOT including both endpoints.
401 * struct GNUNET_PeerIdentity trail[]
406 * P2P Verify Successor Message.
408 struct PeerVerifySuccessorMessage
411 * Type: #GNUNET_MESSAGE_TYPE_XDHT_P2P_VERIFY_SUCCESSOR
413 struct GNUNET_MessageHeader header;
416 * Peer which wants to verify its successor.
418 struct GNUNET_PeerIdentity source_peer;
421 * Source Peer's current successor.
423 struct GNUNET_PeerIdentity successor;
426 * Identifier of trail to reach from source_peer to successor.
428 struct GNUNET_HashCode trail_id;
430 /* List of the peers which are part of trail to reach from source_peer
431 * to successor, NOT including them
432 * struct GNUNET_PeerIdentity trail[]
437 * P2P Verify Successor Result Message
439 struct PeerVerifySuccessorResultMessage
442 * Type: #GNUNET_MESSAGE_TYPE_XDHT_P2P_VERIFY_SUCCESSOR_RESULT
444 struct GNUNET_MessageHeader header;
447 * Peer which sent the request to verify its successor.
449 struct GNUNET_PeerIdentity querying_peer;
452 * Successor to which PeerVerifySuccessorMessage was sent.
454 struct GNUNET_PeerIdentity current_successor;
457 * Current Predecessor of source_successor. It can be same as querying peer
458 * or different. In case it is different then it can be querying_peer's
459 * probable successor.
461 struct GNUNET_PeerIdentity probable_successor;
464 * Trail identifier of trail from querying_peer to current_successor.
466 struct GNUNET_HashCode trail_id;
469 * Direction in which we are looking at the trail.
471 uint32_t trail_direction;
473 /* In case probable_successor != querying_peer, then trail to reach from
474 * querying_peer to probable_successor, NOT including end points.
475 * struct GNUNET_PeerIdentity trail[]
480 * P2P Notify New Successor Message.
482 struct PeerNotifyNewSuccessorMessage
485 * Type: #GNUNET_MESSAGE_TYPE_XDHT_P2P_NOTIFY_NEW_SUCCESSOR
487 struct GNUNET_MessageHeader header;
490 * Peer which wants to notify its new successor.
492 struct GNUNET_PeerIdentity source_peer;
495 * New successor of source_peer.
497 struct GNUNET_PeerIdentity new_successor;
500 * Unique identifier of the trail from source_peer to new_successor,
501 * NOT including the endpoints.
503 struct GNUNET_HashCode trail_id;
505 /* List of peers in trail from source_peer to new_successor,
506 * NOT including the endpoints.
507 * struct GNUNET_PeerIdentity trail[]
512 * P2P Trail Compression Message.
514 struct PeerTrailCompressionMessage
517 * Type: #GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_COMPRESSION
519 struct GNUNET_MessageHeader header;
522 * Source peer of this trail.
524 struct GNUNET_PeerIdentity source_peer;
527 * Trail from source_peer to destination_peer compressed such that
528 * new_first_friend is the first hop in the trail from source to
531 struct GNUNET_PeerIdentity new_first_friend;
534 * Unique identifier of trail.
536 struct GNUNET_HashCode trail_id;
541 * P2P Trail Tear Down message.
543 struct PeerTrailTearDownMessage
546 * Type: #GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_TEARDOWN
548 struct GNUNET_MessageHeader header;
551 * Unique identifier of the trail.
553 struct GNUNET_HashCode trail_id;
556 * Direction of trail.
558 uint32_t trail_direction;
563 * P2P Trail Rejection Message.
565 struct PeerTrailRejectionMessage
568 * Type: #GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_SETUP_REJECTION
570 struct GNUNET_MessageHeader header;
573 * Peer which wants to set up the trail.
575 struct GNUNET_PeerIdentity source_peer;
578 * Peer which sent trail rejection message as it it congested.
580 struct GNUNET_PeerIdentity congested_peer;
583 * Peer identity closest to this value will be finger of
586 uint64_t ultimate_destination_finger_value;
589 * Is source_peer trying to setup the trail to its predecessor or finger.
591 uint32_t is_predecessor;
594 * Identifier for the trail that source peer is trying to setup.
596 struct GNUNET_HashCode trail_id;
599 * Relative time for which congested_peer will remain congested.
601 struct GNUNET_TIME_Relative congestion_time;
603 /* Trail_list from source_peer to peer which sent the message for trail setup
604 * to congested peer. This trail does NOT include source_peer.
605 struct GNUNET_PeerIdnetity trail[]*/
609 * P2P Add Trail Message.
611 struct PeerAddTrailMessage
614 * Type: #GNUNET_MESSAGE_TYPE_XDHT_P2P_ADD_TRAIL
616 struct GNUNET_MessageHeader header;
619 * Source of the routing trail.
621 struct GNUNET_PeerIdentity source_peer;
624 * Destination of the routing trail.
626 struct GNUNET_PeerIdentity destination_peer;
629 * Unique identifier of the trail from source_peer to destination_peer,
630 * NOT including the endpoints.
632 struct GNUNET_HashCode trail_id;
634 /* Trail from source peer to destination peer, NOT including them.
635 * struct GNUNET_PeerIdentity trail[]
639 GNUNET_NETWORK_STRUCT_END
642 * Linked list of messages to send to a particular other peer.
644 struct P2PPendingMessage
647 * Pointer to next item in the list
649 struct P2PPendingMessage *next;
652 * Pointer to previous item in the list
654 struct P2PPendingMessage *prev;
657 * Message importance level. FIXME: used? useful?
659 unsigned int importance;
662 * When does this message time out?
664 struct GNUNET_TIME_Absolute timeout;
667 * Actual message to be sent, allocated at the end of the struct:
668 * // msg = (cast) &pm[1];
669 * // memcpy (&pm[1], data, len);
671 const struct GNUNET_MessageHeader *msg;
676 * Entry in friend_peermap.
683 struct GNUNET_PeerIdentity id;
686 * Number of trails for which this friend is the first hop or if the friend
689 unsigned int trails_count;
692 * Count of outstanding messages for this friend.
694 unsigned int pending_count;
697 * In case not 0, then amount of time for which this friend is congested.
699 struct GNUNET_TIME_Absolute congestion_timestamp;
702 * Head of pending messages to be sent to this friend.
704 struct P2PPendingMessage *head;
707 * Tail of pending messages to be sent to this friend.
709 struct P2PPendingMessage *tail;
712 * Core handle for sending messages to this friend.
714 struct GNUNET_CORE_TransmitHandle *th;
719 * An individual element of the trail to reach to a finger.
724 * Pointer to next item in the list
726 struct Trail_Element *next;
729 * Pointer to prev item in the list
731 struct Trail_Element *prev;
734 * An element in this trail.
736 struct GNUNET_PeerIdentity peer;
740 * FIXME: removed first_friend_trails_count, need to write a function
741 * to calculate each time we need it. Else, keep a pointer to first
742 * friend of in the trail.
743 * Information about an individual trail.
750 struct Trail_Element *trail_head;
755 struct Trail_Element *trail_tail;
758 * Unique identifier of this trail.
760 struct GNUNET_HashCode trail_id;
763 * Length of trail pointed
765 unsigned int trail_length;
768 * Is there a valid trail entry.
770 unsigned int is_present;
774 * An entry in finger_table
781 struct GNUNET_PeerIdentity finger_identity;
784 * Is any finger stored at this finger index.
786 unsigned int is_present;
789 * Index in finger peer map
791 uint32_t finger_table_index;
794 * Number of trails setup so far for this finger.
795 * Should not cross MAXIMUM_TRAILS_PER_FINGER.
797 uint32_t trails_count;
800 * Array of trails to reach to this finger.
802 struct Trail trail_list[MAXIMUM_TRAILS_PER_FINGER];
807 * Data structure to keep track of closest peer seen so far in find_successor()
812 * Destination finger vaule.
814 uint64_t destination_finger_value;
817 * Is finger value predecessor or any other finge
819 unsigned int is_predecessor;
822 * Trail id to reach to peer.
824 struct GNUNET_HashCode trail_id;
827 * FIXME: see the usage of this field and write comment.
829 struct GNUNET_PeerIdentity next_hop;
832 * Next destination. In case of friend and my_identity , it is same as next_hop
833 * In case of finger it is finger identity.
835 struct GNUNET_PeerIdentity best_known_destination;
839 * FIXME: now I have removed the first_friend_trail_count,
840 * Need to update the code to find the count.
841 * Data structure to store the trail chosen to reach to finger.
843 struct Selected_Finger_Trail
846 * First friend in the trail to reach finger.
848 struct FriendInfo friend;
851 * Identifier of this trail.
853 struct GNUNET_HashCode trail_id;
856 * Total number of peers in this trail.
858 unsigned int trail_length;
862 * Task that sends FIND FINGER TRAIL requests. This task is started when we have
863 * get our first friend.
865 static GNUNET_SCHEDULER_TaskIdentifier find_finger_trail_task;
868 * Identity of this peer.
870 static struct GNUNET_PeerIdentity my_identity;
873 * Peer map of all the friends of a peer
875 static struct GNUNET_CONTAINER_MultiPeerMap *friend_peermap;
878 * Array of all the fingers.
880 static struct FingerInfo finger_table [MAX_FINGERS];
885 static struct GNUNET_CORE_Handle *core_api;
888 * The current finger index that we have want to find trail to. We start the
889 * search with value = 0, i.e. successor and then go to PREDCESSOR_FINGER_ID
890 * and decrement it. For any index 63 <= index < 0, if finger is same as successor,
891 * we reset this index to 0.
893 static unsigned int current_search_finger_index;
897 * Called when core is ready to send a message we asked for
898 * out to the destination.
900 * @param cls the 'struct FriendInfo' of the target friend
901 * @param size number of bytes available in buf
902 * @param buf where the callee should write the message
903 * @return number of bytes written to buf
906 core_transmit_notify (void *cls, size_t size, void *buf)
908 struct FriendInfo *peer = cls;
910 struct P2PPendingMessage *pending;
915 while ((NULL != (pending = peer->head)) &&
916 (0 == GNUNET_TIME_absolute_get_remaining (pending->timeout).rel_value_us))
918 peer->pending_count--;
919 GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, pending);
920 GNUNET_free (pending);
924 /* no messages pending */
930 GNUNET_CORE_notify_transmit_ready (core_api, GNUNET_NO,
931 GNUNET_CORE_PRIO_BEST_EFFORT,
932 GNUNET_TIME_absolute_get_remaining
933 (pending->timeout), &peer->id,
934 ntohs (pending->msg->size),
935 &core_transmit_notify, peer);
936 GNUNET_break (NULL != peer->th);
940 while ((NULL != (pending = peer->head)) &&
941 (size - off >= (msize = ntohs (pending->msg->size))))
943 GNUNET_STATISTICS_update (GDS_stats,
945 ("# Bytes transmitted to other peers"), msize,
947 memcpy (&cbuf[off], pending->msg, msize);
949 peer->pending_count--;
950 GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, pending);
951 GNUNET_free (pending);
953 if (peer->head != NULL)
956 GNUNET_CORE_notify_transmit_ready (core_api, GNUNET_NO,
957 GNUNET_CORE_PRIO_BEST_EFFORT,
958 GNUNET_TIME_absolute_get_remaining
959 (pending->timeout), &peer->id, msize,
960 &core_transmit_notify, peer);
961 GNUNET_break (NULL != peer->th);
969 * Transmit all messages in the friend's message queue.
971 * @param peer message queue to process
974 process_friend_queue (struct FriendInfo *peer)
976 struct P2PPendingMessage *pending;
978 if (NULL == (pending = peer->head))
980 if (NULL != peer->th)
983 GNUNET_STATISTICS_update (GDS_stats,
985 ("# Bytes of bandwidth requested from core"),
986 ntohs (pending->msg->size), GNUNET_NO);
989 GNUNET_CORE_notify_transmit_ready (core_api, GNUNET_NO,
991 GNUNET_TIME_absolute_get_remaining
992 (pending->timeout), &peer->id,
993 ntohs (pending->msg->size),
994 &core_transmit_notify, peer);
995 GNUNET_break (NULL != peer->th);
1000 * Return friend corresponding to peer.
1005 GDS_NEIGHBOURS_get_friend (struct GNUNET_PeerIdentity peer)
1007 struct FriendInfo *friend;
1008 GNUNET_assert (NULL != (friend =
1009 GNUNET_CONTAINER_multipeermap_get (friend_peermap, &peer)));
1015 * Construct a trail setup message and forward it to target_friend
1016 * @param source_peer Peer which wants to setup the trail
1017 * @param ultimate_destination_finger_value Peer identity closest to this value
1018 * will be finger to @a source_peer
1019 * @param best_known_destination Best known destination (could be finger or friend)
1020 * which should get this message. In case it is
1021 * friend, then it is same as target_friend
1022 * @param target_friend Friend to which message is forwarded now.
1023 * @param trail_length Total number of peers in trail setup so far.
1024 * @param trail_peer_list Trail setup so far
1025 * @param is_predecessor Is @a source_peer looking for trail to a predecessor or not.
1026 * @param trail_id Unique identifier for the trail we are trying to setup.
1027 * @param intermediate_trail_id Trail id of intermediate trail to reach to
1028 * best_known_destination when its a finger. If not
1029 * used then set to 0.
1032 GDS_NEIGHBOURS_send_trail_setup (struct GNUNET_PeerIdentity source_peer,
1033 uint64_t ultimate_destination_finger_value,
1034 struct GNUNET_PeerIdentity best_known_destination,
1035 struct FriendInfo *target_friend,
1036 unsigned int trail_length,
1037 const struct GNUNET_PeerIdentity *trail_peer_list,
1038 unsigned int is_predecessor,
1039 struct GNUNET_HashCode trail_id,
1040 struct GNUNET_HashCode *intermediate_trail_id)
1042 struct P2PPendingMessage *pending;
1043 struct PeerTrailSetupMessage *tsm;
1044 struct GNUNET_PeerIdentity *peer_list;
1047 msize = sizeof (struct PeerTrailSetupMessage) +
1048 (trail_length * sizeof (struct GNUNET_PeerIdentity));
1050 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1056 if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
1058 GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1062 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1063 pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
1064 tsm = (struct PeerTrailSetupMessage *) &pending[1];
1065 pending->msg = &tsm->header;
1066 tsm->header.size = htons (msize);
1067 tsm->header.type = htons (GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_SETUP);
1068 tsm->final_destination_finger_value = GNUNET_htonll (ultimate_destination_finger_value);
1069 tsm->source_peer = source_peer;
1070 tsm->best_known_destination = best_known_destination;
1071 tsm->is_predecessor = htonl (is_predecessor);
1072 tsm->trail_id = trail_id;
1074 if (NULL == intermediate_trail_id)
1075 memset (&tsm->intermediate_trail_id, 0, sizeof (tsm->intermediate_trail_id));
1077 tsm->intermediate_trail_id = *intermediate_trail_id;
1079 if (trail_length > 0)
1081 peer_list = (struct GNUNET_PeerIdentity *) &tsm[1];
1082 memcpy (peer_list, trail_peer_list, trail_length * sizeof(struct GNUNET_PeerIdentity));
1085 GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
1086 target_friend->pending_count++;
1087 process_friend_queue (target_friend);
1092 * Construct a trail setup result message and forward it to target friend.
1093 * @param querying_peer Peer which sent the trail setup request and should get
1095 * @param Finger Peer to which the trail has been setup to.
1096 * @param target_friend Friend to which this message should be forwarded.
1097 * @param trail_length Numbers of peers in the trail.
1098 * @param trail_peer_list Peers which are part of the trail from q
1099 * querying_peer to Finger, NOT including them.
1100 * @param is_predecessor Is @a Finger predecessor to @a querying_peer
1101 * @param ultimate_destination_finger_value Value to which @a finger is the closest
1103 * @param trail_id Unique identifier of the trail.
1106 GDS_NEIGHBOURS_send_trail_setup_result (struct GNUNET_PeerIdentity querying_peer,
1107 struct GNUNET_PeerIdentity finger,
1108 struct FriendInfo *target_friend,
1109 unsigned int trail_length,
1110 const struct GNUNET_PeerIdentity *trail_peer_list,
1111 unsigned int is_predecessor,
1112 uint64_t ultimate_destination_finger_value,
1113 struct GNUNET_HashCode trail_id)
1115 struct P2PPendingMessage *pending;
1116 struct PeerTrailSetupResultMessage *tsrm;
1117 struct GNUNET_PeerIdentity *peer_list;
1120 msize = sizeof (struct PeerTrailSetupResultMessage) +
1121 (trail_length * sizeof (struct GNUNET_PeerIdentity));
1123 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1129 if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
1131 GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1135 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1136 pending->importance = 0;
1137 pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
1138 tsrm = (struct PeerTrailSetupResultMessage *) &pending[1];
1139 pending->msg = &tsrm->header;
1140 tsrm->header.size = htons (msize);
1141 tsrm->header.type = htons (GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_SETUP_RESULT);
1142 tsrm->querying_peer = querying_peer;
1143 tsrm->finger_identity = finger;
1144 tsrm->is_predecessor = htonl (is_predecessor);
1145 tsrm->trail_id = trail_id;
1146 tsrm->ulitmate_destination_finger_value =
1147 GNUNET_htonll (ultimate_destination_finger_value);
1148 peer_list = (struct GNUNET_PeerIdentity *) &tsrm[1];
1149 if (trail_length > 0)
1151 memcpy (peer_list, trail_peer_list, trail_length * sizeof (struct GNUNET_PeerIdentity));
1153 /* Send the message to chosen friend. */
1154 GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
1155 target_friend->pending_count++;
1156 process_friend_queue (target_friend);
1161 * Send trail rejection message to target friend
1162 * @param source_peer Peer which is trying to setup the trail.
1163 * @param ultimate_destination_finger_value Peer closest to this value will be
1164 * @a source_peer's finger
1165 * @param congested_peer Peer which sent this message as it is congested.
1166 * @param is_predecessor Is source_peer looking for trail to a predecessor or not.
1167 * @param trail_peer_list Trails seen so far in trail setup before getting rejected
1168 * by congested_peer. This does not include @a source_peer
1169 * @param trail_length Total number of peers in trail_peer_list, not including
1171 * @param trail_id Unique identifier of this trail.
1172 * @param congestion_timeout Duration given by congested peer as an estimate of
1173 * how long it may remain congested.
1176 GDS_NEIGHBOURS_send_trail_rejection (struct GNUNET_PeerIdentity source_peer,
1177 uint64_t ultimate_destination_finger_value,
1178 struct GNUNET_PeerIdentity congested_peer,
1179 unsigned int is_predecessor,
1180 const struct GNUNET_PeerIdentity *trail_peer_list,
1181 unsigned int trail_length,
1182 struct GNUNET_HashCode trail_id,
1183 struct FriendInfo *target_friend,
1184 const struct GNUNET_TIME_Relative congestion_timeout)
1186 struct PeerTrailRejectionMessage *trm;
1187 struct P2PPendingMessage *pending;
1188 struct GNUNET_PeerIdentity *peer_list;
1191 msize = sizeof (struct PeerTrailRejectionMessage) +
1192 (trail_length * sizeof (struct GNUNET_PeerIdentity));
1194 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1200 if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
1202 GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1206 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1207 pending->importance = 0;
1208 pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
1209 trm = (struct PeerTrailRejectionMessage *)&pending[1];
1210 pending->msg = &trm->header;
1211 trm->header.size = htons (msize);
1212 trm->header.type = htons (GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_SETUP_REJECTION);
1213 trm->source_peer = source_peer;
1214 trm->congested_peer = congested_peer;
1215 trm->congestion_time = congestion_timeout;
1216 trm->is_predecessor = htonl (is_predecessor);
1217 trm->trail_id = trail_id;
1218 trm->ultimate_destination_finger_value = GNUNET_htonll (ultimate_destination_finger_value);
1220 peer_list = (struct GNUNET_PeerIdentity *) &trm[1];
1221 if (trail_length > 0)
1223 memcpy (peer_list, trail_peer_list, trail_length * sizeof (struct GNUNET_PeerIdentity));
1226 /* Send the message to chosen friend. */
1227 GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
1228 target_friend->pending_count++;
1229 process_friend_queue (target_friend);
1234 * Construct a verify successor message and forward it to target_friend.
1235 * @param source_peer Peer which wants to verify its successor.
1236 * @param successor Peer which is @a source_peer's current successor.
1237 * @param trail_id Unique Identifier of trail from @a source_peer to @a successor,
1238 * NOT including them.
1239 * @param trail List of peers which are part of trail to reach from @a source_peer
1240 * to @a successor, NOT including them.
1241 * @param trail_length Total number of peers in @a trail.
1242 * @param target_friend Next friend to get this message.
1245 GDS_NEIGHBOURS_send_verify_successor_message (struct GNUNET_PeerIdentity source_peer,
1246 struct GNUNET_PeerIdentity successor,
1247 struct GNUNET_HashCode trail_id,
1248 struct GNUNET_PeerIdentity *trail,
1249 unsigned int trail_length,
1250 struct FriendInfo *target_friend)
1252 struct PeerVerifySuccessorMessage *vsm;
1253 struct P2PPendingMessage *pending;
1254 struct GNUNET_PeerIdentity *peer_list;
1257 msize = sizeof (struct PeerVerifySuccessorMessage);
1258 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1264 if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
1266 GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1270 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1271 pending->importance = 0; /* FIXME */
1272 pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
1273 vsm = (struct PeerVerifySuccessorMessage *) &pending[1];
1274 pending->msg = &vsm->header;
1275 vsm->header.size = htons (msize);
1276 vsm->header.type = htons (GNUNET_MESSAGE_TYPE_XDHT_P2P_VERIFY_SUCCESSOR);
1277 vsm->source_peer = source_peer;
1278 vsm->successor = successor;
1279 vsm->trail_id = trail_id;
1281 if (trail_length > 0)
1283 peer_list = (struct GNUNET_PeerIdentity *) &vsm[1];
1284 memcpy (peer_list, trail, trail_length * sizeof (struct GNUNET_PeerIdentity));
1287 /* Send the message to chosen friend. */
1288 GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
1289 target_friend->pending_count++;
1290 process_friend_queue (target_friend);
1295 * FIXME: In every function we pass target friend except for this one.
1296 * so, either change everything or this one. also, should se just store
1297 * the pointer to friend in routing table rather than gnunet_peeridentity.
1298 * if yes then we should keep friend info in.h andmake lot of changes.
1299 * Construct a trail teardown message and forward it to target friend.
1300 * @param trail_id Unique identifier of the trail.
1301 * @param trail_direction Direction of trail.
1302 * @param target_friend Friend to get this message.
1305 GDS_NEIGHBOURS_send_trail_teardown (struct GNUNET_HashCode trail_id,
1306 unsigned int trail_direction,
1307 struct GNUNET_PeerIdentity *peer)
1309 struct PeerTrailTearDownMessage *ttdm;
1310 struct P2PPendingMessage *pending;
1311 struct FriendInfo *target_friend;
1314 msize = sizeof (struct PeerTrailTearDownMessage);
1316 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1322 GNUNET_assert (NULL != (target_friend =
1323 GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer)));
1325 if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
1327 GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1331 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1332 pending->importance = 0; /* FIXME */
1333 pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
1334 ttdm = (struct PeerTrailTearDownMessage *) &pending[1];
1335 pending->msg = &ttdm->header;
1336 ttdm->header.size = htons (msize);
1337 ttdm->header.type = htons (GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_TEARDOWN);
1338 ttdm->trail_id = trail_id;
1339 ttdm->trail_direction = htonl (trail_direction);
1341 /* Send the message to chosen friend. */
1343 GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
1344 target_friend->pending_count++;
1345 process_friend_queue (target_friend);
1350 * Construct a verify successor result message and send it to target_friend
1351 * @param querying_peer Peer which sent the verify successor message.
1352 * @param source_successor Current_successor of @a querying_peer.
1353 * @param current_predecessor Current predecessor of @a successor. Could be same
1354 * or different from @a querying_peer.
1355 * @param trail_id Unique identifier of the trail from @a querying_peer to
1356 * @a successor, NOT including them.
1357 * @param trail List of peers which are part of trail from @a querying_peer to
1358 * @a successor, NOT including them.
1359 * @param trail_length Total number of peers in @a trail
1360 * @param trail_direction Direction in which we are sending the message. In this
1361 * case we are sending result from @a successor to @a querying_peer.
1362 * @param target_friend Next friend to get this message.
1365 GDS_NEIGHBOURS_send_verify_successor_result (struct GNUNET_PeerIdentity querying_peer,
1366 struct GNUNET_PeerIdentity current_successor,
1367 struct GNUNET_PeerIdentity probable_successor,
1368 struct GNUNET_HashCode trail_id,
1369 const struct GNUNET_PeerIdentity *trail,
1370 unsigned int trail_length,
1371 enum GDS_ROUTING_trail_direction trail_direction,
1372 struct FriendInfo *target_friend)
1374 struct PeerVerifySuccessorResultMessage *vsmr;
1375 struct P2PPendingMessage *pending;
1376 struct GNUNET_PeerIdentity *peer_list;
1379 msize = sizeof (struct PeerVerifySuccessorResultMessage) +
1380 (trail_length * sizeof(struct GNUNET_PeerIdentity));
1382 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1388 if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
1390 GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1394 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1395 pending->importance = 0; /* FIXME */
1396 pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
1397 vsmr = (struct PeerVerifySuccessorResultMessage *) &pending[1];
1398 pending->msg = &vsmr->header;
1399 vsmr->header.size = htons (msize);
1400 vsmr->header.type = htons (GNUNET_MESSAGE_TYPE_XDHT_P2P_VERIFY_SUCCESSOR_RESULT);
1401 vsmr->querying_peer = querying_peer;
1402 vsmr->current_successor = current_successor;
1403 vsmr->probable_successor = probable_successor;
1404 vsmr->trail_direction = htonl (trail_direction);
1405 vsmr->trail_id = trail_id;
1407 if (trail_length > 0)
1409 peer_list = (struct GNUNET_PeerIdentity *) &vsmr[1];
1410 memcpy (peer_list, trail, trail_length * sizeof (struct GNUNET_PeerIdentity));
1413 /* Send the message to chosen friend. */
1414 GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
1415 target_friend->pending_count++;
1416 process_friend_queue (target_friend);
1421 * Construct a notify new successor message and send it to target_friend
1422 * @param source_peer Peer which wants to notify to its new successor that it
1423 * could be its predecessor.
1424 * @param successor New successor of @a source_peer
1425 * @param successor_trail List of peers in Trail to reach from
1426 * @a source_peer to @a new_successor, NOT including
1428 * @param successor_trail_length Total number of peers in @a new_successor_trail.
1429 * @param successor_trail_id Unique identifier of @a new_successor_trail.
1430 * @param target_friend Next friend to get this message.
1433 GDS_NEIGHBOURS_send_notify_new_successor (struct GNUNET_PeerIdentity source_peer,
1434 struct GNUNET_PeerIdentity successor,
1435 const struct GNUNET_PeerIdentity *successor_trail,
1436 unsigned int successor_trail_length,
1437 struct GNUNET_HashCode succesor_trail_id,
1438 struct FriendInfo *target_friend)
1440 struct PeerNotifyNewSuccessorMessage *nsm;
1441 struct P2PPendingMessage *pending;
1442 struct GNUNET_PeerIdentity *peer_list;
1445 msize = sizeof (struct PeerNotifyNewSuccessorMessage) +
1446 (successor_trail_length * sizeof(struct GNUNET_PeerIdentity));
1448 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1454 if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
1456 GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1460 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1461 pending->importance = 0; /* FIXME */
1462 pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
1463 nsm = (struct PeerNotifyNewSuccessorMessage *) &pending[1];
1464 pending->msg = &nsm->header;
1465 nsm->header.size = htons (msize);
1466 nsm->header.type = htons (GNUNET_MESSAGE_TYPE_XDHT_P2P_NOTIFY_NEW_SUCCESSOR);
1467 nsm->new_successor = successor;
1468 nsm->source_peer = source_peer;
1469 nsm->trail_id = succesor_trail_id;
1471 if (successor_trail_length > 0)
1473 peer_list = (struct GNUNET_PeerIdentity *) &nsm[1];
1474 memcpy (peer_list, successor_trail,
1475 successor_trail_length * sizeof (struct GNUNET_PeerIdentity));
1478 /* Send the message to chosen friend. */
1479 GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
1480 target_friend->pending_count++;
1481 process_friend_queue (target_friend);
1486 * Construct an add_trail message and send it to target_friend
1487 * @param source_peer Source of the trail.
1488 * @param destination_peer Destination of the trail.
1489 * @param trail_id Unique identifier of the trail from
1490 * @a source_peer to @a destination_peer, NOT including the endpoints.
1491 * @param trail List of peers in Trail from @a source_peer to @a destination_peer,
1492 * NOT including the endpoints.
1493 * @param trail_length Total number of peers in @a trail.
1494 * @param target_friend Next friend to get this message.
1497 GDS_NEIGHBOURS_send_add_trail (struct GNUNET_PeerIdentity source_peer,
1498 struct GNUNET_PeerIdentity destination_peer,
1499 struct GNUNET_HashCode trail_id,
1500 const struct GNUNET_PeerIdentity *trail,
1501 unsigned int trail_length,
1502 struct FriendInfo *target_friend)
1504 struct PeerAddTrailMessage *adm;
1505 struct GNUNET_PeerIdentity *peer_list;
1506 struct P2PPendingMessage *pending;
1509 msize = sizeof (struct PeerAddTrailMessage) +
1510 (trail_length * sizeof(struct GNUNET_PeerIdentity));
1512 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1518 if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
1520 GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
1524 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1525 pending->importance = 0; /* FIXME */
1526 pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
1527 adm = (struct PeerAddTrailMessage *) &pending[1];
1528 pending->msg = &adm->header;
1529 adm->header.size = htons (msize);
1530 adm->header.type = htons (GNUNET_MESSAGE_TYPE_XDHT_P2P_ADD_TRAIL);
1531 adm->source_peer = source_peer;
1532 adm->destination_peer = destination_peer;
1533 adm->trail_id = trail_id;
1535 peer_list = (struct GNUNET_PeerIdentity *)&adm[1];
1536 memcpy (peer_list, trail, sizeof (struct GNUNET_PeerIdentity) * trail_length);
1538 /* Send the message to chosen friend. */
1539 GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
1540 target_friend->pending_count++;
1541 process_friend_queue (target_friend);
1547 * Construct a trail compression message and send it to target_friend.
1548 * @param source_peer Source of the trail.
1549 * @param trail_id Unique identifier of trail.
1550 * @param first_friend First hop in compressed trail to reach from source to finger
1551 * @param target_friend Next friend to get this message.
1554 GDS_NEIGHBOURS_send_trail_compression (struct GNUNET_PeerIdentity source_peer,
1555 struct GNUNET_HashCode trail_id,
1556 struct GNUNET_PeerIdentity first_friend,
1557 struct FriendInfo *target_friend)
1559 struct P2PPendingMessage *pending;
1560 struct PeerTrailCompressionMessage *tcm;
1563 msize = sizeof (struct PeerTrailCompressionMessage);
1565 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1571 if (target_friend->pending_count >= MAXIMUM_PENDING_PER_FRIEND)
1573 GNUNET_STATISTICS_update (GDS_stats,
1574 gettext_noop ("# P2P messages dropped due to full queue"),
1578 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
1579 pending->importance = 0; /* FIXME */
1580 pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
1581 tcm = (struct PeerTrailCompressionMessage *) &pending[1];
1582 pending->msg = &tcm->header;
1583 tcm->header.size = htons (msize);
1584 tcm->header.type = htons (GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_COMPRESSION);
1585 tcm->source_peer = source_peer;
1586 tcm->new_first_friend = first_friend;
1587 tcm->trail_id = trail_id;
1589 GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
1590 target_friend->pending_count++;
1591 process_friend_queue (target_friend);
1597 * Search my location in trail.
1598 * @param trail List of peers
1599 * @return my_index if found
1600 * -1 if no entry found.
1603 search_my_index (const struct GNUNET_PeerIdentity *trail,
1608 for (i = 0; i < trail_length; i++)
1610 if (0 == GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &trail[i]))
1619 * Check if the friend is congested or have reached maximum number of trails
1620 * it can be part of of.
1621 * @param friend Friend to be checked.
1622 * @return #GNUNET_YES if friend is not congested or have not crossed threshold.
1623 * #GNUNET_NO if friend is either congested or have crossed threshold
1626 is_friend_congested (struct FriendInfo *friend)
1628 if ((friend->trails_count < TRAILS_THROUGH_FRIEND_THRESHOLD) &&
1629 ((0 == GNUNET_TIME_absolute_get_remaining
1630 (friend->congestion_timestamp).rel_value_us)))
1638 * Iterate over the list of all the trails of a finger. In case the first
1639 * friend to reach the finger has reached trail threshold or is congested,
1640 * then don't select it. In case there multiple available good trails to reach
1641 * to Finger, choose the one with shortest trail length.
1642 * Note: We use length as parameter. But we can use any other suitable parameter
1644 * @param finger Finger
1645 * @return struct Selected_Finger_Trail which contains the first friend , trail id
1646 * and trail length. NULL in case none of the trails are free.
1648 static struct Selected_Finger_Trail *
1649 select_finger_trail (struct FingerInfo *finger)
1651 struct FriendInfo *friend;
1652 struct Trail *iterator;
1653 struct Selected_Finger_Trail *finger_trail;
1655 unsigned int flag = 0;
1658 finger_trail = GNUNET_new (struct Selected_Finger_Trail);
1660 /* It can never happen that we have a finger (which is not a friend or my identity),
1661 and we don't have a trail to reach to it. */
1662 GNUNET_assert (finger->trails_count > 0);
1664 for (i = 0; i < finger->trails_count; i++)
1666 iterator = &finger->trail_list[i];
1668 /* No trail stored at this index. */
1669 if (GNUNET_NO == iterator->is_present)
1672 friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
1673 &iterator->trail_head->peer);
1675 /* First friend to reach trail is not free. */
1676 if (GNUNET_YES == is_friend_congested (friend))
1681 /* This is the first time we enter the loop. Set finger trail length to
1682 * trail length of this trail. */
1686 finger_trail->trail_length = iterator->trail_length;
1688 else if (finger_trail->trail_length > iterator->trail_length)
1690 /* Check if the trail length of this trail is least seen so far. If yes then
1691 set finger_trail to this trail.*/
1692 finger_trail->friend = *friend;
1693 finger_trail->trail_id = iterator->trail_id;
1694 finger_trail->trail_length = iterator->trail_length;
1698 /* All the first friend in all the trails to reach to finger are either
1699 congested or have crossed trail threshold. */
1700 if (j == finger->trails_count)
1703 return finger_trail;
1708 * FIXME; not handling the wrap around logic correctly.
1709 * Select closest finger to value.
1710 * @param peer1 First peer
1711 * @param peer2 Second peer
1712 * @param value Value to be compare
1713 * @return Closest peer
1715 static struct GNUNET_PeerIdentity *
1716 select_closest_finger (struct GNUNET_PeerIdentity *peer1,
1717 struct GNUNET_PeerIdentity *peer2,
1720 uint64_t peer1_value;
1721 uint64_t peer2_value;
1723 memcpy (&peer1_value, peer1, sizeof (uint64_t));
1724 memcpy (&peer2_value, peer2, sizeof (uint64_t));
1725 peer1_value = GNUNET_ntohll (peer1_value);
1726 peer2_value = GNUNET_ntohll (peer2_value);
1727 value = GNUNET_ntohll (value); //FIXME: Is it correct to do it here?
1728 // we do it when we get from the network.
1730 if (peer1_value == value)
1735 if (peer2_value == value)
1740 if (peer2_value < peer1_value)
1742 if ((peer2_value < value) && (value < peer1_value))
1746 else if (((peer1_value < value) && (value < PEER_IDENTITES_WRAP_AROUND)) ||
1747 ((0 < value) && (value < peer2_value)))
1753 if (peer1_value < peer2_value)
1755 if ((peer1_value < value) && (value < peer2_value))
1759 else if (((peer2_value < value) && (value < PEER_IDENTITES_WRAP_AROUND)) ||
1760 ((0 < value) && (value < peer1_value)))
1770 * Select closest predecessor to value.
1771 * @param peer1 First peer
1772 * @param peer2 Second peer
1773 * @param value Value to be compare
1774 * @return Peer which precedes value in the network.
1776 static struct GNUNET_PeerIdentity *
1777 select_closest_predecessor (struct GNUNET_PeerIdentity *peer1,
1778 struct GNUNET_PeerIdentity *peer2,
1781 uint64_t peer1_value;
1782 uint64_t peer2_value;
1784 memcpy (&peer1_value, peer1, sizeof (uint64_t));
1785 memcpy (&peer2_value, peer2, sizeof (uint64_t));
1786 peer1_value = GNUNET_ntohll (peer1_value);
1787 peer2_value = GNUNET_ntohll (peer2_value);
1789 if (peer1_value == value)
1792 if (peer2_value == value)
1795 if (peer1_value < peer2_value)
1797 if ((peer1_value < value) && (value < peer2_value))
1799 else if (((peer2_value < value) && (value < PEER_IDENTITES_WRAP_AROUND)) ||
1800 ((PEER_IDENTITES_WRAP_AROUND > value) && (value < peer1_value)))
1804 if (peer2_value < peer1_value)
1806 if ((peer2_value < value) && (value < peer1_value))
1808 else if (((peer1_value < value) && (value < PEER_IDENTITES_WRAP_AROUND)) ||
1809 ((PEER_IDENTITES_WRAP_AROUND > value) && (value < peer2_value)))
1817 * Select the closest peer among two peers (which should not be same)
1818 * with respect to value and finger_table_index
1819 * NOTE: peer1 != peer2
1820 * @param peer1 First peer
1821 * @param peer2 Second peer
1822 * @param value Value relative to which we find the closest
1823 * @param finger_table_index Index in finger map. If equal to PREDECESSOR_FINGER_ID,
1824 * then we use different logic than other
1825 * finger_table_index
1826 * @return Closest peer among two peers.
1828 static struct GNUNET_PeerIdentity *
1829 select_closest_peer (struct GNUNET_PeerIdentity *peer1,
1830 struct GNUNET_PeerIdentity *peer2,
1832 unsigned int finger_table_index)
1834 struct GNUNET_PeerIdentity *closest_peer;
1836 if (PREDECESSOR_FINGER_ID == finger_table_index)
1837 closest_peer = select_closest_predecessor (peer1, peer2, value);
1839 closest_peer = select_closest_finger (peer1, peer2, value);
1841 return closest_peer;
1846 * FIXME: better names and more refactoring.
1847 * Compare FINGER entry with current successor. If finger's first friend of all
1848 * its trail is not congested and has not crossed trail threshold, then check
1849 * if finger peer identity is closer to final_destination_finger_value than
1850 * current_successor. If yes then update current_successor.
1851 * @param current_successor[in/out]
1854 static struct Closest_Peer *
1855 compare_finger_and_current_successor (struct Closest_Peer *current_closest_peer)
1857 struct FingerInfo *finger;
1858 struct FriendInfo *friend;
1859 struct GNUNET_PeerIdentity *closest_peer;
1860 struct Selected_Finger_Trail *finger_trail;
1863 /* Iterate over finger table. */
1864 for (i = 0; i < MAX_FINGERS; i++)
1866 finger = &finger_table[i];
1868 /* No valid entry at this index, go to next element.*/
1869 if (GNUNET_NO == finger->is_present)
1872 /* If my identity is same as current closest peer then don't consider me*/
1874 GNUNET_CRYPTO_cmp_peer_identity (&finger->finger_identity,
1875 ¤t_closest_peer->best_known_destination))
1878 /* If I am my own finger, then ignore this finger. */
1879 if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger->finger_identity,
1883 /* If finger is a friend, then do nothing. As we have already checked
1884 * for each friend in compare_friend_and_current_successor(). */
1886 (friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
1887 &finger->finger_identity)))
1890 /* We have a finger which not a friend, not my identity */
1891 /* Choose one of the trail to reach to finger. */
1892 finger_trail = select_finger_trail (finger);
1894 /* In case no trail found, ignore this finger. */
1895 if (NULL == finger_trail)
1898 closest_peer = select_closest_peer (&finger->finger_identity,
1899 ¤t_closest_peer->best_known_destination,
1900 current_closest_peer->destination_finger_value,
1901 current_closest_peer->is_predecessor);
1902 if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger->finger_identity,
1905 current_closest_peer->best_known_destination = finger->finger_identity;
1906 current_closest_peer->next_hop = finger_trail->friend.id;
1907 current_closest_peer->trail_id = finger_trail->trail_id;
1911 return current_closest_peer;
1916 * Compare friend entry with current successor.
1917 * If friend identity and current_successor is same, then do nothing.
1918 * If friend is not congested and has not crossed trail threshold, then check
1919 * if friend peer identity is closer to final_destination_finger_value than
1920 * current_successor. If yes then update current_successor.
1921 * @param cls closure
1922 * @param key current public key
1923 * @param value struct Closest_Peer
1924 * @return #GNUNET_YES if we should continue to iterate,
1925 * #GNUNET_NO if not.
1928 compare_friend_and_current_closest_peer (void *cls,
1929 const struct GNUNET_PeerIdentity *key,
1932 struct FriendInfo *friend = value;
1933 struct Closest_Peer *current_closest_peer = cls;
1934 struct GNUNET_PeerIdentity *closest_peer;
1936 /* If friend is either congested or has crossed threshold, then don't consider
1938 if (GNUNET_YES == is_friend_congested (friend))
1941 /* If current_closest_peer and friend identity are same, then do nothing.*/
1943 GNUNET_CRYPTO_cmp_peer_identity (&friend->id,
1944 ¤t_closest_peer->best_known_destination))
1947 closest_peer = select_closest_peer (&friend->id,
1948 ¤t_closest_peer->best_known_destination,
1949 current_closest_peer->destination_finger_value,
1950 current_closest_peer->is_predecessor);
1952 /* Is friend the closest successor? */
1953 if (0 == GNUNET_CRYPTO_cmp_peer_identity (&friend->id, closest_peer))
1955 current_closest_peer->best_known_destination = friend->id;
1956 current_closest_peer->next_hop = friend->id;
1964 * Initialize current_successor to my_identity.
1965 * @param my_identity My peer identity
1966 * @return current_successor
1968 static struct Closest_Peer *
1969 init_current_successor (struct GNUNET_PeerIdentity my_identity,
1970 uint64_t destination_finger_value,
1971 unsigned int is_predecessor)
1973 struct Closest_Peer *current_closest_peer;
1975 current_closest_peer = GNUNET_new (struct Closest_Peer);
1976 memset (¤t_closest_peer->trail_id, 0, sizeof (current_closest_peer->trail_id));
1977 current_closest_peer->destination_finger_value = destination_finger_value;
1978 current_closest_peer->is_predecessor = is_predecessor;
1979 current_closest_peer->next_hop = my_identity;
1980 current_closest_peer->best_known_destination = my_identity;
1982 return current_closest_peer;
1987 * FIXME: can we just send gnunet_peeridentit and not gnunet_peeridentity *?
1988 * Find the successor for destination_finger_value among my_identity, all my
1989 * friend and all my fingers. Don't consider friends or fingers which are either
1990 * congested or have crossed the threshold.
1991 * @param destination_finger_value Peer closest to this value will be the next successor.
1992 * @param local_best_known_destination[out] Updated to my_identity if I am the
1993 * final destination. Updated to friend
1994 * identity in case a friend is successor,
1995 * updated to finger in case finger is the
1997 * @param new_intermediate_trail_id[out] In case a finger is the
1998 * @a local_best_known_destination,
1999 * then it is the trail to reach it. Else
2001 * @param is_predecessor Are we looking for predecessor or finger?
2002 * @return Next hop to reach to local_best_known_destination. In case my_identity
2003 * or a friend is a local_best_known_destination, then
2004 * next_hop = local_best_known_destination. Else
2005 * next_hop is the first friend to reach to finger (local_best_known_destination)
2007 static struct GNUNET_PeerIdentity *
2008 find_successor (uint64_t destination_finger_value,
2009 struct GNUNET_PeerIdentity *local_best_known_destination,
2010 struct GNUNET_HashCode *new_intermediate_trail_id,
2011 unsigned int is_predecessor)
2013 struct Closest_Peer *current_closest_peer;
2014 struct GNUNET_PeerIdentity *next_hop;
2016 /* Initialize current_successor to my_identity. */
2017 current_closest_peer = init_current_successor (my_identity,
2018 destination_finger_value,
2021 /* Compare each friend entry with current_successor and update current_successor
2022 * with friend if its closest. */
2025 GNUNET_CONTAINER_multipeermap_iterate (friend_peermap,
2026 &compare_friend_and_current_closest_peer,
2027 current_closest_peer));
2029 /* Compare each finger entry with current_successor and update current_successor
2030 * with finger if its closest. */
2031 compare_finger_and_current_successor (current_closest_peer);
2033 *local_best_known_destination = current_closest_peer->best_known_destination;
2034 new_intermediate_trail_id = ¤t_closest_peer->trail_id;
2035 next_hop = GNUNET_new (struct GNUNET_PeerIdentity);
2036 *next_hop = current_closest_peer->next_hop;
2043 * Construct a Put message and send it to target_peer.
2044 * @param key Key for the content
2045 * @param block_type Type of the block
2046 * @param options Routing options
2047 * @param desired_replication_level Desired replication count
2048 * @param best_known_dest Peer to which this message should reach eventually,
2049 * as it is best known destination to me.
2050 * @param intermediate_trail_id Trail id in case
2051 * @param target_peer Peer to which this message will be forwarded.
2052 * @param hop_count Number of hops traversed so far.
2053 * @param put_path_length Total number of peers in @a put_path
2054 * @param put_path Number of peers traversed so far
2055 * @param expiration_time When does the content expire
2056 * @param data Content to store
2057 * @param data_size Size of content @a data in bytes
2060 GDS_NEIGHBOURS_send_put (const struct GNUNET_HashCode *key,
2061 enum GNUNET_BLOCK_Type block_type,
2062 enum GNUNET_DHT_RouteOption options,
2063 uint32_t desired_replication_level,
2064 struct GNUNET_PeerIdentity *best_known_dest,
2065 struct GNUNET_HashCode *intermediate_trail_id,
2066 struct GNUNET_PeerIdentity *target_peer,
2068 uint32_t put_path_length,
2069 struct GNUNET_PeerIdentity *put_path,
2070 struct GNUNET_TIME_Absolute expiration_time,
2071 const void *data, size_t data_size)
2073 struct PeerPutMessage *ppm;
2074 struct P2PPendingMessage *pending;
2075 struct FriendInfo *target_friend;
2076 struct GNUNET_PeerIdentity *pp;
2077 struct GNUNET_PeerIdentity local_best_known_dest;
2080 msize = put_path_length * sizeof (struct GNUNET_PeerIdentity) + data_size +
2081 sizeof (struct PeerPutMessage);
2083 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
2085 put_path_length = 0;
2086 msize = data_size + sizeof (struct PeerPutMessage);
2089 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
2095 /* This is the first call made from clients file. So, we should search for the
2097 if (NULL == target_peer)
2100 struct GNUNET_PeerIdentity *next_hop;
2102 memcpy (&key_value, key, sizeof (uint64_t));
2103 next_hop = find_successor (key_value, &local_best_known_dest,
2104 intermediate_trail_id, GDS_FINGER_TYPE_NON_PREDECESSOR);
2105 if (0 == GNUNET_CRYPTO_cmp_peer_identity (&local_best_known_dest, &my_identity))
2107 /* I am the destination but we have already done datacache_put in client file. */
2111 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
2112 GNUNET_free (next_hop);
2116 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, target_peer);
2118 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
2119 pending->timeout = expiration_time;
2120 ppm = (struct PeerPutMessage *) &pending[1];
2121 pending->msg = &ppm->header;
2122 ppm->header.size = htons (msize);
2123 ppm->header.type = htons (GNUNET_MESSAGE_TYPE_XDHT_P2P_PUT);
2124 ppm->options = htonl (options);
2125 ppm->block_type = htonl (block_type);
2126 ppm->hop_count = htonl (hop_count + 1);
2127 ppm->desired_replication_level = htonl (desired_replication_level);
2128 ppm->put_path_length = htonl (put_path_length);
2129 ppm->expiration_time = GNUNET_TIME_absolute_hton (expiration_time);
2130 if (NULL == best_known_dest)
2131 ppm->best_known_destination = local_best_known_dest;
2133 ppm->best_known_destination = *best_known_dest;
2135 if (NULL == intermediate_trail_id)
2136 memset (&ppm->intermediate_trail_id, 0, sizeof (ppm->intermediate_trail_id));
2138 ppm->intermediate_trail_id = *intermediate_trail_id;
2139 pp = (struct GNUNET_PeerIdentity *) &ppm[1];
2140 if (put_path_length != 0)
2142 memcpy (pp, put_path,
2143 sizeof (struct GNUNET_PeerIdentity) * put_path_length);
2145 memcpy (&pp[put_path_length], data, data_size);
2146 GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
2147 target_friend->pending_count++;
2148 process_friend_queue (target_friend);
2153 * Construct a Get message and send it to target_peer.
2154 * @param key Key for the content
2155 * @param block_type Type of the block
2156 * @param options Routing options
2157 * @param desired_replication_level Desired replication count
2158 * @param best_known_dest Peer which should get this message. Same as target peer
2159 * if best_known_dest is a friend else its a finger.
2160 * @param intermediate_trail_id Trail id to reach to @a best_known_dest
2161 * in case it is a finger else set to 0.
2162 * @param target_peer Peer to which this message will be forwarded.
2163 * @param hop_count Number of hops traversed so far.
2164 * @param data Content to store
2165 * @param data_size Size of content @a data in bytes
2166 * @param get_path_length Total number of peers in @a get_path
2167 * @param get_path Number of peers traversed so far
2170 GDS_NEIGHBOURS_send_get (const struct GNUNET_HashCode *key,
2171 enum GNUNET_BLOCK_Type block_type,
2172 enum GNUNET_DHT_RouteOption options,
2173 uint32_t desired_replication_level,
2174 const struct GNUNET_PeerIdentity *best_known_dest,
2175 struct GNUNET_HashCode *intermediate_trail_id,
2176 struct GNUNET_PeerIdentity *target_peer,
2178 uint32_t get_path_length,
2179 struct GNUNET_PeerIdentity *get_path)
2181 struct PeerGetMessage *pgm;
2182 struct P2PPendingMessage *pending;
2183 struct FriendInfo *target_friend;
2184 struct GNUNET_PeerIdentity local_best_known_dest;
2185 struct GNUNET_PeerIdentity *gp;
2188 msize = sizeof (struct PeerGetMessage) +
2189 (get_path_length * sizeof (struct GNUNET_PeerIdentity));
2191 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
2193 get_path_length = 0;
2194 msize = sizeof (struct PeerPutMessage);
2197 if (msize > GNUNET_SERVER_MAX_MESSAGE_SIZE)
2203 /* This is the first time we got request from our own client file. */
2204 if (NULL == target_peer)
2206 struct GNUNET_PeerIdentity *next_hop;
2209 memcpy (&key_value, key, sizeof (uint64_t)); //FIXME: endianess of key?
2211 /* Find the next destination to forward the packet. */
2212 next_hop = find_successor (key_value, &local_best_known_dest,
2213 intermediate_trail_id, GDS_FINGER_TYPE_NON_PREDECESSOR);
2215 /* I am the destination. I have the data. */
2216 if (0 == GNUNET_CRYPTO_cmp_peer_identity (&my_identity,
2217 &local_best_known_dest))
2219 GDS_DATACACHE_handle_get (key,block_type, NULL, 0,
2220 NULL, 0, 1, &my_identity, NULL,&my_identity);
2226 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
2228 GNUNET_free (next_hop);
2232 local_best_known_dest = *best_known_dest;
2233 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, target_peer);
2236 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
2237 pending->importance = 0; /* FIXME */
2238 pgm = (struct PeerGetMessage *) &pending[1];
2239 pending->msg = &pgm->header;
2240 pgm->header.size = htons (msize);
2241 pgm->header.type = htons (GNUNET_MESSAGE_TYPE_XDHT_P2P_GET);
2242 pgm->get_path_length = htonl (get_path_length);
2243 pgm->best_known_destination = local_best_known_dest;
2245 if (NULL == intermediate_trail_id)
2246 memset (&pgm->intermediate_trail_id, 0, sizeof (pgm->intermediate_trail_id));
2248 pgm->intermediate_trail_id = *intermediate_trail_id;
2249 pgm->hop_count = htonl (hop_count + 1);
2251 if (get_path_length != 0)
2253 gp = (struct GNUNET_PeerIdentity *) &pgm[1];
2254 memcpy (gp, get_path, get_path_length * sizeof (struct GNUNET_PeerIdentity));
2256 GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
2257 target_friend->pending_count++;
2258 process_friend_queue (target_friend);
2263 * Send the get result to requesting client.
2264 * @param key Key of the requested data.
2265 * @param type Block type
2266 * @param target_peer Next peer to forward the message to.
2267 * @param source_peer Peer which has the data for the key.
2268 * @param put_path_length Number of peers in @a put_path
2269 * @param put_path Path taken to put the data at its stored location.
2270 * @param get_path_length Number of peers in @a get_path
2271 * @param get_path Path taken to reach to the location of the key.
2272 * @param expiration When will this result expire?
2273 * @param data Payload to store
2274 * @param data_size Size of the @a data
2277 GDS_NEIGHBOURS_send_get_result (const struct GNUNET_HashCode *key,
2278 enum GNUNET_BLOCK_Type type,
2279 struct GNUNET_PeerIdentity *target_peer,
2280 struct GNUNET_PeerIdentity *source_peer,
2281 unsigned int put_path_length,
2282 const struct GNUNET_PeerIdentity *put_path,
2283 unsigned int get_path_length,
2284 struct GNUNET_PeerIdentity *get_path,
2285 struct GNUNET_TIME_Absolute expiration,
2286 const void *data, size_t data_size)
2288 struct PeerGetResultMessage *get_result;
2289 struct GNUNET_PeerIdentity *get_result_path;
2290 struct GNUNET_PeerIdentity *pp;
2291 struct P2PPendingMessage *pending;
2292 struct FriendInfo *target_friend;
2293 int current_path_index;
2296 msize = get_path_length * sizeof (struct GNUNET_PeerIdentity) + data_size +
2297 sizeof (struct PeerPutMessage);
2299 if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
2305 current_path_index = -1;
2306 if(get_path_length > 0)
2308 current_path_index = search_my_index(get_path, get_path_length);
2309 if (-1 == current_path_index)
2315 if (0 == current_path_index)
2317 GDS_CLIENTS_handle_reply (expiration, key, get_path_length,
2318 get_path, put_path_length,
2319 put_path, type, data_size, data);
2323 pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
2324 pending->importance = 0;
2325 get_result = (struct PeerGetResultMessage *)&pending[1];
2326 pending->msg = &get_result->header;
2327 get_result->header.size = htons (msize);
2328 get_result->header.type = htons (GNUNET_MESSAGE_TYPE_XDHT_P2P_GET_RESULT);
2329 get_result->key = *key;
2330 /* FIXME: check if you are passing the correct querying_peer as described in
2331 the get_result documentation. */
2332 memcpy (&(get_result->querying_peer), source_peer, sizeof (struct GNUNET_PeerIdentity));
2333 get_result->expiration_time = expiration;
2334 get_result_path = (struct GNUNET_PeerIdentity *)&get_result[1];
2335 if (get_path_length != 0)
2336 memcpy (get_result_path, get_path,
2337 sizeof (struct GNUNET_PeerIdentity) * get_path_length);
2338 memcpy (&get_result_path[get_path_length], data, data_size);
2340 /* FIXME: Is this correct? */
2341 if (put_path_length != 0)
2343 pp = (struct GNUNET_PeerIdentity *)&get_result_path[1];
2344 memcpy (pp, put_path,sizeof (struct GNUNET_PeerIdentity) * put_path_length);
2347 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
2348 &get_result_path[current_path_index - 1]);
2349 GNUNET_CONTAINER_DLL_insert_tail (target_friend->head, target_friend->tail, pending);
2350 target_friend->pending_count++;
2351 process_friend_queue (target_friend);
2356 * Randomly choose one of your friends (which is not congested and have not crossed
2357 * trail threshold) from the friends_peer map
2358 * @return Friend Randomly chosen friend.
2359 * NULL in case friend peermap is empty, or all the friends are either
2360 * congested or have crossed trail threshold.
2362 static struct FriendInfo *
2363 select_random_friend ()
2365 unsigned int current_size;
2368 struct GNUNET_CONTAINER_MultiPeerMapIterator *iter;
2369 struct GNUNET_PeerIdentity key_ret;
2370 struct FriendInfo *friend;
2372 current_size = GNUNET_CONTAINER_multipeermap_size (friend_peermap);
2375 if (0 == current_size)
2378 index = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, current_size);
2379 iter = GNUNET_CONTAINER_multipeermap_iterator_create (friend_peermap);
2381 /* Iterate till you don't reach to index. */
2382 for (j = 0; j < index ; j++)
2383 GNUNET_assert (GNUNET_YES ==
2384 GNUNET_CONTAINER_multipeermap_iterator_next (iter, NULL, NULL));
2387 /* Reset the index in friend peermap to 0 as we reached to the end. */
2388 if (j == current_size)
2391 GNUNET_CONTAINER_multipeermap_iterator_destroy (iter);
2392 iter = GNUNET_CONTAINER_multipeermap_iterator_create (friend_peermap);
2396 /* Get the friend stored at the index, j*/
2397 GNUNET_assert (GNUNET_YES ==
2398 GNUNET_CONTAINER_multipeermap_iterator_next (iter,
2400 (const void **)&friend));
2402 /* This friend is not congested and has not crossed trail threshold. */
2403 if ((TRAILS_THROUGH_FRIEND_THRESHOLD > friend->trails_count) &&
2404 (0 == GNUNET_TIME_absolute_get_remaining (friend->congestion_timestamp).rel_value_us))
2410 } while (j != index);
2412 GNUNET_CONTAINER_multipeermap_iterator_destroy (iter);
2418 * Compute 64 bit value of finger_identity corresponding to a finger index using
2421 * n.finger[i] = n + pow (2,i),
2423 * n.finger[i] = n - 1, where
2426 * n.finger[i] = 64 bit finger value
2427 * @param finger_index Index corresponding to which we calculate 64 bit value.
2428 * @return 64 bit value.
2431 compute_finger_identity_value (unsigned int finger_index)
2435 memcpy (&my_id64, &my_identity, sizeof (uint64_t));
2436 my_id64 = GNUNET_ntohll (my_id64);
2438 /* Are we looking for immediate predecessor? */
2439 if (PREDECESSOR_FINGER_ID == finger_index)
2440 return (my_id64 -1);
2442 return (my_id64 + (unsigned long) pow (2, finger_index));
2447 * Choose a random friend. Start looking for the trail to reach to
2448 * finger identity corresponding to current_search_finger_index through
2449 * this random friend.
2451 * @param cls closure for this task
2452 * @param tc the context under which the task is running
2455 send_find_finger_trail_message (void *cls,
2456 const struct GNUNET_SCHEDULER_TaskContext *tc)
2458 struct FriendInfo *target_friend;
2459 struct GNUNET_TIME_Relative next_send_time;
2460 struct GNUNET_HashCode trail_id;
2461 unsigned int is_predecessor;
2462 uint64_t finger_id_value;
2464 /* Schedule another send_find_finger_trail_message task. */
2465 next_send_time.rel_value_us =
2466 DHT_FIND_FINGER_TRAIL_INTERVAL.rel_value_us +
2467 GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK,
2468 DHT_FIND_FINGER_TRAIL_INTERVAL.rel_value_us);
2469 find_finger_trail_task =
2470 GNUNET_SCHEDULER_add_delayed (next_send_time, &send_find_finger_trail_message,
2473 /* No space in my routing table. (Source and destination peers also store entries
2474 * in their routing table). */
2475 if (GNUNET_YES == GDS_ROUTING_threshold_reached())
2478 target_friend = select_random_friend ();
2479 if (NULL == target_friend)
2484 finger_id_value = compute_finger_identity_value (current_search_finger_index);
2485 if (PREDECESSOR_FINGER_ID == current_search_finger_index)
2490 /* Generate a unique trail id for trail we are trying to setup. */
2491 GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_STRONG,
2492 &trail_id, sizeof (trail_id));
2493 GDS_NEIGHBOURS_send_trail_setup (my_identity, finger_id_value,
2494 target_friend->id, target_friend, 0, NULL,
2495 is_predecessor, trail_id, NULL);
2500 * In case there are already maximum number of possible trails to reach to a
2501 * finger, then check if the new trail's length is lesser than any of the
2503 * If yes then replace that old trail by new trail.
2505 * Note: Here we are taking length as a parameter to choose the best possible
2506 * trail, but there could be other parameters also like:
2507 * 1. duration of existence of a trail - older the better.
2508 * 2. if the new trail is completely disjoint than the
2509 * other trails, then may be choosing it is better.
2511 * @param existing_finger
2512 * @param new_finger_trail
2513 * @param new_finger_trail_length
2514 * @param new_finger_trail_id
2517 select_and_replace_trail (struct FingerInfo *existing_finger,
2518 const struct GNUNET_PeerIdentity *new_trail,
2519 unsigned int new_trail_length,
2520 struct GNUNET_HashCode new_trail_id)
2522 struct Trail *trail_list_iterator;
2523 unsigned int largest_trail_length;
2524 unsigned int largest_trail_index;
2525 struct Trail_Element *trail_element;
2528 largest_trail_length = new_trail_length;
2529 largest_trail_index = MAXIMUM_TRAILS_PER_FINGER + 1;
2531 GNUNET_assert (MAXIMUM_TRAILS_PER_FINGER == existing_finger->trails_count);
2533 for (i = 0; i < existing_finger->trails_count; i++)
2535 trail_list_iterator = &existing_finger->trail_list[i];
2536 if (trail_list_iterator->trail_length > largest_trail_length)
2538 largest_trail_length = trail_list_iterator->trail_length;
2539 largest_trail_index = i;
2543 if (largest_trail_index == (MAXIMUM_TRAILS_PER_FINGER + 1))
2545 // tear down new trail: it's not better than the existing ones
2549 /* Send trail teardown message across the replaced trail. */
2550 struct Trail *replace_trail = &existing_finger->trail_list[largest_trail_index];
2552 GDS_NEIGHBOURS_send_trail_teardown (replace_trail->trail_id,
2553 GDS_ROUTING_SRC_TO_DEST,
2554 &replace_trail->trail_head->peer);
2555 /* Free the trail. */
2556 while (NULL != (trail_element = replace_trail->trail_head))
2558 GNUNET_CONTAINER_DLL_remove (replace_trail->trail_head,
2559 replace_trail->trail_tail, trail_element);
2560 GNUNET_free_non_null (trail_element);
2563 /* Add new trial at that location. */
2565 while (i < new_trail_length)
2567 struct Trail_Element *element = GNUNET_new (struct Trail_Element);
2568 element->peer = new_trail[i];
2570 GNUNET_CONTAINER_DLL_insert_tail (replace_trail->trail_head,
2571 replace_trail->trail_tail,
2578 * Check if the new trail to reach to finger is unique or do we already have
2579 * such a trail present for finger.
2580 * @param existing_finger Finger identity
2581 * @param new_trail New trail to reach @a existing_finger
2582 * @param trail_length Total number of peers in new_trail.
2583 * @return #GNUNET_YES if the new trail is unique
2584 * #GNUNET_NO if same trail is already present.
2587 is_new_trail_unique (struct FingerInfo *existing_finger,
2588 const struct GNUNET_PeerIdentity *new_trail,
2589 unsigned int trail_length)
2591 struct Trail *trail_list_iterator;
2592 struct Trail_Element *trail_element;
2595 int trail_unique = GNUNET_NO;
2597 for (i = 0; i < existing_finger->trails_count; i++)
2599 trail_list_iterator = &existing_finger->trail_list[i];
2600 if (trail_list_iterator->trail_length != trail_length)
2602 trail_element = trail_list_iterator->trail_head;
2603 for (j = 0; j < trail_list_iterator->trail_length; j++)
2605 if (0 != GNUNET_CRYPTO_cmp_peer_identity (&new_trail[j],
2606 &trail_element->peer))
2608 trail_unique = GNUNET_YES;
2613 return trail_unique;
2618 * Add a new trail to existing finger.
2619 * @param existing_finger
2620 * @param new_finger_trail
2621 * @param new_finger_trail_length
2622 * @param new_finger_trail_id
2625 add_new_trail (struct FingerInfo *existing_finger,
2626 const struct GNUNET_PeerIdentity *new_trail,
2627 unsigned int new_trail_length,
2628 struct GNUNET_HashCode new_trail_id)
2630 struct Trail *trail_list_iterator;
2631 struct FriendInfo *first_friend;
2634 if (GNUNET_NO == is_new_trail_unique (existing_finger, new_trail,
2640 // FIXME checking trail_head is NOT a valid way to verify an open slot
2641 for (i = 0; existing_finger->trail_list[i].trail_head != NULL; i++)
2642 GNUNET_assert (i < MAXIMUM_TRAILS_PER_FINGER);
2644 trail_list_iterator = &existing_finger->trail_list[i];
2646 if (new_trail_length > 0)
2647 first_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
2650 first_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
2651 &(existing_finger->finger_identity));
2652 first_friend->trails_count++;
2653 /* FIXME; we removed this field but read fixme. */
2654 //trail_list_iterator->first_friend_trail_count = first_friend->trails_count;
2655 trail_list_iterator->trail_length = new_trail_length;
2657 for (i = 0; i < new_trail_length; i++)
2659 struct Trail_Element *element;
2660 element = GNUNET_new (struct Trail_Element);
2662 element->peer = new_trail[i];
2663 GNUNET_CONTAINER_DLL_insert_tail (trail_list_iterator->trail_head,
2664 trail_list_iterator->trail_tail,
2667 existing_finger->trails_count++;
2672 * Send trail teardown message for a specific trail of a finger.
2673 * @param finger Finger whose trail is to be removed.
2674 * @param trail List of peers in trail from me to a finger, NOT including
2678 send_trail_teardown (struct FingerInfo *finger,
2679 struct Trail *trail)
2681 /* FIXME: Now source also stores a trail entry in its routing table. before
2682 sending the trail teardown, you should get next_hop from routing table.
2683 If it is NULL, it means that path is broken, then remove the trail.
2684 return a value to calling function so that if all trails are removed,
2685 then remove finger. */
2686 /* We should decerement the friend trail count here. */
2687 struct FriendInfo *friend;
2689 GNUNET_assert (NULL != (friend =
2690 GNUNET_CONTAINER_multipeermap_get (friend_peermap,
2691 &trail->trail_head->peer)));
2693 //friend->trails_count--;
2694 GDS_NEIGHBOURS_send_trail_teardown (trail->trail_id,
2695 GDS_ROUTING_SRC_TO_DEST,
2696 &trail->trail_head->peer);
2701 * Send trail teardown message across all the trails to reach to finger.
2702 * @param finger Finger whose all the trail should be freed.
2705 send_all_finger_trails_teardown (struct FingerInfo *finger)
2707 struct Trail *trail;
2710 for (i = 0; i < finger->trails_count; i++)
2712 trail = &finger->trail_list[i];
2713 if (trail->trail_length > 0)
2715 /* decerement the friend trails count. */
2716 send_trail_teardown (finger, trail);
2723 * Free a specific trail
2724 * @param trail List of peers to be freed.
2727 free_trail (struct Trail *trail)
2729 struct Trail_Element *trail_element;
2731 while (NULL != (trail_element = trail->trail_head))
2733 GNUNET_CONTAINER_DLL_remove (trail->trail_head,
2736 GNUNET_free_non_null (trail_element);
2738 trail->trail_head = NULL;
2739 trail->trail_tail = NULL;
2744 * Free finger and its trail.
2745 * @param finger Finger to be freed.
2748 free_finger (struct FingerInfo *finger, unsigned int finger_table_index)
2750 struct Trail *trail;
2753 for (i = 0; i < finger->trails_count; i++)
2755 trail = &finger->trail_list[i];
2756 if (GNUNET_NO == trail->is_present)
2759 if (trail->trail_length > 0)
2763 finger->is_present = GNUNET_NO;
2764 memset ((void *)&finger_table[finger_table_index], 0, sizeof (finger_table[finger_table_index]));
2769 * FIXME: ensure that you are not adding any trail to reach to a friend which
2770 * is a finger. Also decide on should you increment trails count of a friend
2771 * which is also a finger.
2772 * Add a new entry in finger table at finger_table_index.
2773 * In case finger identity is me or a friend, then don't add a trail. NOTE
2774 * trail length to reach to a finger can be 0 only if the finger is a friend
2776 * In case a finger is a friend, then increment the trails count of the friend.
2777 * @param finger_identity Peer Identity of new finger
2778 * @param finger_trail Trail to reach from me to finger (excluding both end points).
2779 * @param finger_trail_length Total number of peers in @a finger_trail.
2780 * @param trail_id Unique identifier of the trail.
2781 * @param finger_table_index Index in finger table.
2784 add_new_finger (struct GNUNET_PeerIdentity finger_identity,
2785 const struct GNUNET_PeerIdentity *finger_trail,
2786 unsigned int finger_trail_length,
2787 struct GNUNET_HashCode trail_id,
2788 unsigned int finger_table_index)
2790 struct FingerInfo *new_entry;
2791 struct FriendInfo *first_trail_hop;
2792 struct Trail *trail;
2795 new_entry = GNUNET_new (struct FingerInfo);
2796 new_entry->finger_identity = finger_identity;
2797 new_entry->finger_table_index = finger_table_index;
2798 new_entry->is_present = GNUNET_YES;
2800 /* If the new entry is my own identity or a friend. */
2801 if ((0 == GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &finger_identity)) ||
2802 (NULL != GNUNET_CONTAINER_multipeermap_get (friend_peermap, &finger_identity)))
2804 new_entry->trails_count = 0;
2805 finger_table[finger_table_index] = *new_entry;
2809 /* finger trail length can be 0 only in case if finger is my identity or
2810 finger is friend. We should never reach here. */
2811 GNUNET_assert (finger_trail_length > 0);
2813 GNUNET_assert (NULL !=
2815 GNUNET_CONTAINER_multipeermap_get (friend_peermap,
2816 &finger_trail[0])));
2817 new_entry->trails_count = 1;
2818 first_trail_hop->trails_count++;
2820 /* Copy the finger trail into trail. */
2821 trail = GNUNET_new (struct Trail);
2822 while (i < finger_trail_length)
2824 struct Trail_Element *element = GNUNET_new (struct Trail_Element);
2826 element->next = NULL;
2827 element->prev = NULL;
2828 element->peer = finger_trail[i];
2829 GNUNET_CONTAINER_DLL_insert_tail (trail->trail_head,
2835 /* Add trail to trail list. */
2836 new_entry->trail_list[0].trail_head = trail->trail_head;
2837 new_entry->trail_list[0].trail_tail = trail->trail_tail;
2838 new_entry->trail_list[0].trail_length = finger_trail_length;
2839 new_entry->trail_list[0].trail_id = trail_id;
2840 new_entry->trail_list[0].is_present = GNUNET_YES;
2841 finger_table[finger_table_index] = *new_entry;
2842 GNUNET_free (new_entry);
2843 GNUNET_free (trail);
2849 * Scan the trail to check if there is any other friend in the trail other than
2850 * first hop. If yes then shortcut the trail, send trail compression message to
2851 * peers which are no longer part of trail and send back the updated trail
2852 * and trail_length to calling function.
2853 * @param finger_identity Finger whose trail we will scan.
2854 * @param finger_trail [in, out] Trail to reach from source to finger,
2855 * @param finger_trail_length Total number of peers in original finger_trail.
2856 * @param finger_trail_id Unique identifier of the finger trail.
2857 * @return updated trail length in case we shortcut the trail, else original
2860 static struct GNUNET_PeerIdentity *
2861 scan_and_compress_trail (struct GNUNET_PeerIdentity finger_identity,
2862 const struct GNUNET_PeerIdentity *trail,
2863 unsigned int trail_length,
2864 struct GNUNET_HashCode trail_id,
2865 int *new_trail_length)
2867 struct FriendInfo *target_friend;
2868 struct GNUNET_PeerIdentity *new_trail;
2871 /* If I am my own finger identity, then we set trail_length = 0.
2872 Note: Here we don't send trail compression message, as no peer in its
2873 trail added an entry in its routing table.*/
2874 if (0 == GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &finger_identity))
2876 *new_trail_length = 0;
2880 /* If finger identity is a friend. */
2881 if (NULL != GNUNET_CONTAINER_multipeermap_get (friend_peermap, &finger_identity))
2883 *new_trail_length = 0;
2885 /* If there is trail to reach this finger/friend */
2886 if (trail_length > 0)
2888 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
2890 /* FIXME: In case its finger == friend, then may be we send a trail
2891 teardown message as it does not make any sense to have any routing e
2892 entry in your own routing table.*/
2893 GDS_NEIGHBOURS_send_trail_compression (my_identity,
2894 trail_id, finger_identity,
2900 /* For other cases, when its neither a friend nor my own identity.*/
2901 for (i = trail_length - 1; i > 0; i--)
2903 /* If the element at this index in trail is a friend. */
2904 if (NULL != GNUNET_CONTAINER_multipeermap_get (friend_peermap, &trail[i]))
2906 struct FriendInfo *target_friend;
2909 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
2911 GDS_NEIGHBOURS_send_trail_compression (my_identity,
2916 /* Copy the trail from index i to index (trail_length -1) into a new trail
2917 * and update new trail length */
2918 new_trail = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity) * i);
2919 while (i < trail_length)
2921 memcpy (&new_trail[j], &trail[i], sizeof(struct GNUNET_PeerIdentity));
2925 *new_trail_length = j+1;
2930 /* If we found no other friend except the first hop, return the original
2932 new_trail = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity) * trail_length);
2933 *new_trail_length = trail_length;
2934 memcpy (new_trail, trail, trail_length * sizeof (struct GNUNET_PeerIdentity));
2940 * Send verify successor message to your current successor over the shortest
2942 * @param successor Current successor.
2945 send_verify_successor_message (struct FingerInfo *successor)
2948 * FIXME: should we send a verify successor message across all the trails
2949 * in case we send through all friends. It complicates the logic, don't
2950 * do it at the moment. Write it as optimization and do it later.
2951 * 1. Here we can have 3 types of fingers
2952 * --> my own identity
2953 * Assumption that the calling function will not send request for
2954 * such successor. Move the logic here.
2955 * --> friend is a finger
2956 * Need to verify if we keep the trails count for a friend. In case of
2957 * friend there is no trail to reach to that friend, so
2958 * 1. no entry in routing table
2960 * 3. no trails count
2961 * 4. but do we increment the count of trails through the friend?
2962 * Trails count is used only to keep a limit on number of trails
2963 * that a friend should be part of. No need to increment the trails
2964 * count for a friend which is a finegr also. so, if finger = friend
2965 * then don't increment the trails count. But if the same friend
2966 * is the first friend to reach to some other finger then increment
2967 * the trails count. Not sure if this design is correct need to verify
2971 struct FriendInfo *target_friend;
2972 struct GNUNET_HashCode trail_id;
2975 /* If successor is a friend. */
2976 if (successor->trails_count == 0)
2978 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
2979 &successor->finger_identity);
2980 memset ((void *)&trail_id, 0 , sizeof (trail_id));
2981 GDS_NEIGHBOURS_send_verify_successor_message (my_identity,
2982 successor->finger_identity,
2988 for (i = 0; i < successor->trails_count; i++)
2990 struct Trail *trail;
2991 struct Trail_Element *element;
2992 unsigned int trail_length;
2995 trail = &successor->trail_list[i];
2997 /* No trail stored at this index. */
2998 if (GNUNET_YES == trail->is_present)
3001 /* Only in case of a friend we can have no trail. We have already handled
3002 * that case. So, now we should never have any such trail. */
3003 GNUNET_assert (trail->trail_length > 0);
3004 trail_id = trail->trail_id;
3005 trail_length = trail->trail_length;
3007 /* Copy the trail into peer list. */
3008 element = trail->trail_head;
3009 struct GNUNET_PeerIdentity peer_list[trail_length];
3010 while (j < trail_length)
3012 peer_list[j] = element->peer;
3013 element = element->next;
3017 GNUNET_assert (NULL != (target_friend =
3018 GNUNET_CONTAINER_multipeermap_get (friend_peermap,
3020 GDS_NEIGHBOURS_send_verify_successor_message (my_identity,
3021 successor->finger_identity,
3022 trail_id, peer_list, trail_length,
3030 * FIXME" clear abstraction of current search finger index and finger map index.
3031 * it never goes to 63. I don't know why
3032 * Update the current search finger index.
3035 update_current_search_finger_index (struct GNUNET_PeerIdentity finger_identity,
3036 unsigned int finger_table_index)
3038 struct FingerInfo *successor;
3040 if (finger_table_index != current_search_finger_index)
3043 successor = &finger_table[0];
3044 if (GNUNET_NO == successor->is_present)
3047 /* We were looking for immediate successor. */
3048 if (0 == current_search_finger_index)
3050 /* Start looking for immediate predecessor. */
3051 current_search_finger_index = PREDECESSOR_FINGER_ID;
3053 /* If I am not my own successor, then send a verify successor message. */
3054 if (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &finger_identity))
3056 send_verify_successor_message (successor);
3061 current_search_finger_index = current_search_finger_index - 1;
3067 * Calculate finger_table_index from initial 64 bit finger identity value that
3068 * we send in trail setup message.
3069 * @param ultimate_destination_finger_value Value that we calculated from our
3070 * identity and finger_table_index.
3071 * @param is_predecessor Is the entry for predecessor or not?
3072 * @return finger_table_index Value between 0 <= finger_table_index <= 64
3073 * -1, if no valid finger_table_index is found.
3076 get_finger_table_index (uint64_t ultimate_destination_finger_value,
3077 unsigned int is_predecessor)
3081 unsigned int finger_table_index;
3083 memcpy (&my_id64, &my_identity, sizeof (uint64_t));
3084 my_id64 = GNUNET_ntohll (my_id64);
3086 /* Is this a predecessor finger? */
3087 if (1 == is_predecessor)
3089 diff = my_id64 - ultimate_destination_finger_value;
3091 finger_table_index = PREDECESSOR_FINGER_ID;
3093 finger_table_index = PREDECESSOR_FINGER_ID + 1; //error value
3098 diff = ultimate_destination_finger_value - my_id64;
3099 finger_table_index = (log10 (diff))/(log10 (2));
3102 return finger_table_index;
3107 * Remove finger and its associated data structures from finger table.
3108 * @param finger Finger to be removed.
3111 remove_existing_finger (struct FingerInfo *existing_finger, unsigned int finger_table_index)
3113 struct FriendInfo *friend;
3114 struct FingerInfo *finger;
3116 finger = &finger_table[finger_table_index];
3117 GNUNET_assert (GNUNET_YES == finger->is_present);
3119 /* If I am my own finger, then we have no trails. */
3120 if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger->finger_identity,
3123 finger->is_present = GNUNET_NO;
3124 memset ((void *)&finger_table[finger_table_index], 0, sizeof (finger_table[finger_table_index]));
3128 /* If finger is a friend, then decrement the trail count and free the finger. */
3129 friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
3130 &finger->finger_identity);
3133 friend->trails_count--;
3134 finger->is_present = GNUNET_NO;
3135 memset ((void *)&finger_table[finger_table_index], 0, sizeof (finger_table[finger_table_index]));
3139 /* For all other fingers, send trail teardown across all the trails to reach
3140 finger, and free the finger. */
3141 send_all_finger_trails_teardown (finger);
3142 free_finger (finger, finger_table_index);
3148 * This is a test function to print all the entries of friend table.
3151 test_friend_peermap_print ()
3153 struct FriendInfo *friend;
3154 struct GNUNET_CONTAINER_MultiPeerMapIterator *friend_iter;
3155 struct GNUNET_PeerIdentity print_peer;
3156 struct GNUNET_PeerIdentity key_ret;
3159 friend_iter = GNUNET_CONTAINER_multipeermap_iterator_create (friend_peermap);
3161 for (i = 0; i < GNUNET_CONTAINER_multipeermap_size (friend_peermap); i++)
3163 if(GNUNET_YES == GNUNET_CONTAINER_multipeermap_iterator_next (friend_iter,
3165 (const void **)&friend))
3167 memcpy (&print_peer, &key_ret, sizeof (struct GNUNET_PeerIdentity));
3168 FPRINTF (stderr,_("\nSUPU %s, %s, %d, friend = %s, friend->trails_count = %d"),
3169 __FILE__, __func__,__LINE__, GNUNET_i2s(&print_peer), friend->trails_count);
3176 * This is a test function, to print all the entries of finger table.
3179 test_finger_table_print()
3181 struct FingerInfo *finger;
3182 struct GNUNET_PeerIdentity print_peer;
3183 struct Trail *trail;
3188 FPRINTF (stderr,_("\nSUPU************ FINGER_TABLE"));
3189 for (i = 0; i < MAX_FINGERS; i++)
3191 finger = &finger_table[i];
3193 if (GNUNET_NO == finger->is_present)
3196 print_peer = finger->finger_identity;
3197 FPRINTF (stderr,_("\nSUPU %s, %s, %d, finger_table[%d] = %s, trails_count = %d"),
3198 __FILE__, __func__,__LINE__,i,GNUNET_i2s (&print_peer), finger->trails_count);
3201 for (j = 0; j < finger->trails_count; j++)
3203 trail = &finger->trail_list[j];
3204 FPRINTF (stderr,_("\nSUPU %s, %s, %d, trail_id[%d]=%s"),__FILE__, __func__,__LINE__,j, GNUNET_h2s(&trail->trail_id));
3205 struct Trail_Element *element;
3206 element = trail->trail_head;
3207 for (k = 0; k < trail->trail_length; k++)
3209 print_peer = element->peer;
3210 FPRINTF (stderr,_("\nSUPU %s, %s, %d,trail[%d] = %s "),__FILE__, __func__,__LINE__,k, GNUNET_i2s(&print_peer));
3211 element = element->next;
3219 * Check if there is already an entry in finger_table at finger_table_index.
3220 * We get the finger_table_index from 64bit finger value we got from the network.
3221 * -- If yes, then select the closest finger.
3222 * -- If new and existing finger are same, then check if you can store more
3224 * -- If yes then add trail, else keep the best trails to reach to the
3226 * -- If the new finger is closest, remove the existing entry, send trail
3227 * teardown message across all the trails to reach the existing entry.
3228 * Add the new finger.
3229 * -- If new and existing finger are different, and existing finger is closest
3231 * -- Update current_search_finger_index.
3232 * @param finger_identity Peer Identity of new finger
3233 * @param finger_trail Trail to reach the new finger
3234 * @param finger_length Total number of peers in @a new_finger_trail.
3235 * @param is_predecessor Is this entry for predecessor in finger_table?
3236 * @param finger_value 64 bit value of finger identity that we got from network.
3237 * @param finger_trail_id Unique identifier of @finger_trail.
3240 finger_table_add (struct GNUNET_PeerIdentity finger_identity,
3241 const struct GNUNET_PeerIdentity *finger_trail,
3242 unsigned int finger_trail_length,
3243 unsigned int is_predecessor,
3244 uint64_t finger_value,
3245 struct GNUNET_HashCode finger_trail_id)
3247 struct FingerInfo *existing_finger;
3248 struct GNUNET_PeerIdentity *closest_peer;
3249 struct GNUNET_PeerIdentity *updated_trail;
3250 struct FingerInfo *successor;
3251 int updated_finger_trail_length;
3252 unsigned int finger_table_index;
3255 test_friend_peermap_print();
3256 test_finger_table_print();
3259 /* Get the finger_table_index corresponding to finger_value we got from network.*/
3260 finger_table_index = get_finger_table_index (finger_value, is_predecessor);
3262 /* Invalid finger_table_index. */
3263 if ((finger_table_index > PREDECESSOR_FINGER_ID))
3265 GNUNET_break_op (0);
3270 /* If the new entry is same as successor then don't add it in finger table,
3271 reset the current search finger index and exit. */
3272 if ((0 != finger_table_index) &&
3273 (PREDECESSOR_FINGER_ID != finger_table_index) &&
3274 (finger_table_index == current_search_finger_index))
3276 successor = &finger_table[0];
3277 GNUNET_assert (GNUNET_YES == successor->is_present);
3278 if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger_identity,
3279 &successor->finger_identity))
3281 current_search_finger_index = 0;
3286 existing_finger = &finger_table[finger_table_index];
3288 updated_finger_trail_length = finger_trail_length;
3290 scan_and_compress_trail (finger_identity, finger_trail,
3291 finger_trail_length, finger_trail_id,
3292 &updated_finger_trail_length);
3293 /* No entry present in finger_table for given finger map index. */
3294 if (GNUNET_NO == existing_finger->is_present)
3296 add_new_finger (finger_identity, updated_trail, updated_finger_trail_length,
3297 finger_trail_id, finger_table_index);
3298 update_current_search_finger_index (finger_identity, finger_table_index);
3299 GNUNET_free_non_null (updated_trail);
3303 /* If existing entry and finger identity are not same. */
3304 if (0 != GNUNET_CRYPTO_cmp_peer_identity (&(existing_finger->finger_identity),
3307 closest_peer = select_closest_peer (&existing_finger->finger_identity,
3309 finger_value, finger_table_index);
3311 /* If the new finger is the closest peer. */
3312 if (0 == GNUNET_CRYPTO_cmp_peer_identity (&finger_identity, closest_peer))
3314 remove_existing_finger (existing_finger, finger_table_index);
3315 add_new_finger (finger_identity, updated_trail, updated_finger_trail_length,
3316 finger_trail_id, finger_table_index);
3321 /* If both new and existing entry are same as my_identity, then do nothing. */
3322 if (0 == GNUNET_CRYPTO_cmp_peer_identity (&(existing_finger->finger_identity),
3325 GNUNET_free_non_null (updated_trail);
3328 /* If the existing finger is not a friend. */
3330 GNUNET_CONTAINER_multipeermap_get (friend_peermap,
3331 &existing_finger->finger_identity))
3333 /* If there is space to store more trails. */
3334 if (existing_finger->trails_count < MAXIMUM_TRAILS_PER_FINGER)
3335 add_new_trail (existing_finger, updated_trail,
3336 finger_trail_length, finger_trail_id);
3338 select_and_replace_trail (existing_finger, updated_trail,
3339 finger_trail_length, finger_trail_id);
3342 update_current_search_finger_index (finger_identity, finger_table_index);
3343 GNUNET_free_non_null (updated_trail);
3349 * Core handler for P2P put messages.
3350 * @param cls closure
3351 * @param peer sender of the request
3352 * @param message message
3353 * @return #GNUNET_OK to keep the connection open,
3354 * #GNUNET_SYSERR to close it (signal serious error)
3357 handle_dht_p2p_put (void *cls, const struct GNUNET_PeerIdentity *peer,
3358 const struct GNUNET_MessageHeader *message)
3360 struct PeerPutMessage *put;
3361 struct GNUNET_PeerIdentity *put_path;
3362 struct GNUNET_HashCode test_key;
3363 enum GNUNET_DHT_RouteOption options;
3364 struct GNUNET_PeerIdentity best_known_dest;
3365 struct GNUNET_HashCode intermediate_trail_id;
3366 struct GNUNET_PeerIdentity *next_hop;
3370 size_t payload_size;
3373 msize = ntohs (message->size);
3374 if (msize < sizeof (struct PeerPutMessage))
3376 GNUNET_break_op (0);
3380 put = (struct PeerPutMessage *) message;
3381 putlen = ntohl (put->put_path_length);
3384 sizeof (struct PeerPutMessage) +
3385 putlen * sizeof (struct GNUNET_PeerIdentity)) ||
3387 GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
3389 GNUNET_break_op (0);
3393 best_known_dest = put->best_known_destination;
3394 put_path = (struct GNUNET_PeerIdentity *) &put[1];
3395 payload = &put_path[putlen];
3396 options = ntohl (put->options);
3397 intermediate_trail_id = put->intermediate_trail_id;
3399 payload_size = msize - (sizeof (struct PeerPutMessage) +
3400 putlen * sizeof (struct GNUNET_PeerIdentity));
3402 switch (GNUNET_BLOCK_get_key (GDS_block_context, ntohl (put->block_type),
3403 payload, payload_size, &test_key))
3406 if (0 != memcmp (&test_key, &put->key, sizeof (struct GNUNET_HashCode)))
3408 char *put_s = GNUNET_strdup (GNUNET_h2s_full (&put->key));
3409 GNUNET_break_op (0);
3410 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3411 "PUT with key `%s' for block with key %s\n",
3412 put_s, GNUNET_h2s_full (&test_key));
3413 GNUNET_free (put_s);
3418 GNUNET_break_op (0);
3421 /* cannot verify, good luck */
3425 if (ntohl (put->block_type) == GNUNET_BLOCK_TYPE_REGEX) /* FIXME: do for all tpyes */
3427 switch (GNUNET_BLOCK_evaluate (GDS_block_context,
3428 ntohl (put->block_type),
3430 NULL, 0, /* bloom filer */
3431 NULL, 0, /* xquery */
3432 payload, payload_size))
3434 case GNUNET_BLOCK_EVALUATION_OK_MORE:
3435 case GNUNET_BLOCK_EVALUATION_OK_LAST:
3438 case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE:
3439 case GNUNET_BLOCK_EVALUATION_RESULT_INVALID:
3440 case GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT:
3441 case GNUNET_BLOCK_EVALUATION_REQUEST_VALID:
3442 case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID:
3443 case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED:
3445 GNUNET_break_op (0);
3450 /* extend 'put path' by sender */
3451 struct GNUNET_PeerIdentity pp[putlen + 1];
3452 if (0 != (options & GNUNET_DHT_RO_RECORD_ROUTE))
3454 memcpy (pp, put_path, putlen * sizeof (struct GNUNET_PeerIdentity));
3461 memcpy (&key_value, &(put->key), sizeof (uint64_t));
3462 if (0 != (GNUNET_CRYPTO_cmp_peer_identity (&best_known_dest, &my_identity)))
3464 next_hop = GDS_ROUTING_get_next_hop (intermediate_trail_id,
3465 GDS_ROUTING_SRC_TO_DEST);
3469 next_hop = find_successor (key_value, &best_known_dest,
3470 &intermediate_trail_id, GDS_FINGER_TYPE_NON_PREDECESSOR);
3473 if (NULL == next_hop)
3475 GNUNET_STATISTICS_update (GDS_stats,
3476 gettext_noop ("# Next hop to forward the packet not found "
3477 "trail setup request, packet dropped."),
3479 return GNUNET_SYSERR;
3482 GDS_CLIENTS_process_put (options,
3483 ntohl (put->block_type),
3484 ntohl (put->hop_count),
3485 ntohl (put->desired_replication_level),
3487 GNUNET_TIME_absolute_ntoh (put->expiration_time),
3492 if (0 == GNUNET_CRYPTO_cmp_peer_identity(&my_identity, &best_known_dest)) /* I am the final destination */
3494 GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (put->expiration_time),
3495 &(put->key),putlen, pp, ntohl (put->block_type),
3496 payload_size, payload);
3497 GNUNET_free_non_null (next_hop);
3502 GDS_NEIGHBOURS_send_put (&put->key,
3503 ntohl (put->block_type),ntohl (put->options),
3504 ntohl (put->desired_replication_level),
3505 &best_known_dest, &intermediate_trail_id, next_hop,
3506 ntohl (put->hop_count), putlen, pp,
3507 GNUNET_TIME_absolute_ntoh (put->expiration_time),
3508 payload, payload_size);
3512 return GNUNET_SYSERR;
3517 * Core handler for p2p get requests.
3519 * @param cls closure
3520 * @param peer sender of the request
3521 * @param message message
3522 * @return #GNUNET_OK to keep the connection open,
3523 * #GNUNET_SYSERR to close it (signal serious error)
3526 handle_dht_p2p_get (void *cls, const struct GNUNET_PeerIdentity *peer,
3527 const struct GNUNET_MessageHeader *message)
3529 const struct PeerGetMessage *get;
3530 const struct GNUNET_PeerIdentity *get_path;
3531 struct GNUNET_PeerIdentity best_known_dest;
3532 struct GNUNET_HashCode intermediate_trail_id;
3533 struct GNUNET_PeerIdentity *next_hop;
3534 uint32_t get_length;
3538 msize = ntohs (message->size);
3539 if (msize < sizeof (struct PeerGetMessage))
3541 GNUNET_break_op (0);
3545 get = (const struct PeerGetMessage *)message;
3546 get_length = ntohl (get->get_path_length);
3547 best_known_dest = get->best_known_destination;
3548 intermediate_trail_id = get->intermediate_trail_id;
3549 get_path = (const struct GNUNET_PeerIdentity *)&get[1];
3552 sizeof (struct PeerGetMessage) +
3553 get_length * sizeof (struct GNUNET_PeerIdentity)) ||
3555 GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
3557 GNUNET_break_op (0);
3561 /* Add sender to get path */
3562 struct GNUNET_PeerIdentity gp[get_length + 1];
3564 memcpy (gp, get_path, get_length * sizeof (struct GNUNET_PeerIdentity));
3565 gp[get_length + 1] = *peer;
3566 get_length = get_length + 1;
3568 memcpy (&key_value, &(get->key), sizeof (uint64_t));
3570 /* I am not the final destination. I am part of trail to reach final dest. */
3571 if (0 != (GNUNET_CRYPTO_cmp_peer_identity (&best_known_dest, &my_identity)))
3573 next_hop = GDS_ROUTING_get_next_hop (intermediate_trail_id,
3574 GDS_ROUTING_SRC_TO_DEST);
3578 /* Get the next hop to pass the message to. */
3579 next_hop = find_successor (key_value, &best_known_dest,
3580 &intermediate_trail_id, GDS_FINGER_TYPE_NON_PREDECESSOR);
3583 if (NULL == next_hop)
3585 GNUNET_STATISTICS_update (GDS_stats,
3586 gettext_noop ("# Next hop to forward the packet not found "
3587 "trail setup request, packet dropped."),
3589 return GNUNET_SYSERR;
3592 /* I am the final destination. */
3593 if (0 == GNUNET_CRYPTO_cmp_peer_identity(&my_identity, &best_known_dest))
3595 struct GNUNET_PeerIdentity final_get_path[get_length+1];
3596 struct GNUNET_PeerIdentity next_hop;
3598 memcpy (final_get_path, gp, get_length * sizeof (struct GNUNET_PeerIdentity));
3599 memcpy (&final_get_path[get_length+1], &my_identity, sizeof (struct GNUNET_PeerIdentity));
3600 get_length = get_length + 1;
3602 /* Get the next hop to pass the get result message. */
3603 memcpy (&next_hop, &final_get_path[get_length-2], sizeof (struct GNUNET_PeerIdentity));
3604 GDS_DATACACHE_handle_get (&(get->key),(get->block_type), NULL, 0, NULL, 0,
3605 get_length, final_get_path, &next_hop, &my_identity);
3610 GDS_NEIGHBOURS_send_get (&(get->key), get->block_type, get->options,
3611 get->desired_replication_level, &best_known_dest,
3612 &intermediate_trail_id, next_hop, 0,
3615 GNUNET_free_non_null (next_hop);
3616 return GNUNET_SYSERR;
3621 * Core handler for get result
3622 * @param cls closure
3623 * @param peer sender of the request
3624 * @param message message
3625 * @return #GNUNET_OK to keep the connection open,
3626 * #GNUNET_SYSERR to close it (signal serious error)
3629 handle_dht_p2p_get_result (void *cls, const struct GNUNET_PeerIdentity *peer,
3630 const struct GNUNET_MessageHeader *message)
3632 struct PeerGetResultMessage *get_result;
3633 struct GNUNET_PeerIdentity *get_path;
3634 struct GNUNET_PeerIdentity *put_path;
3636 size_t payload_size;
3638 unsigned int getlen;
3639 unsigned int putlen;
3640 int current_path_index;
3642 msize = ntohs (message->size);
3643 if (msize < sizeof (struct PeerGetResultMessage))
3645 GNUNET_break_op (0);
3649 get_result = (struct PeerGetResultMessage *)message;
3650 getlen = ntohl (get_result->get_path_length);
3651 putlen = ntohl (get_result->put_path_length);
3654 sizeof (struct PeerGetResultMessage) +
3655 getlen * sizeof (struct GNUNET_PeerIdentity) +
3656 putlen * sizeof (struct GNUNET_PeerIdentity)) ||
3658 GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity) ||
3660 GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity))))
3662 GNUNET_break_op (0);
3666 get_path = (struct GNUNET_PeerIdentity *) &get_result[1];
3667 payload = &get_path[getlen];
3668 payload_size = msize - (sizeof (struct PeerGetResultMessage) +
3669 getlen * sizeof (struct GNUNET_PeerIdentity));
3672 put_path = &get_path[1];
3674 if (0 == (GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &(get_path[0]))))
3676 GDS_CLIENTS_handle_reply (get_result->expiration_time, &(get_result->key),
3677 getlen, get_path, putlen,
3678 put_path, get_result->type, payload_size, payload);
3683 current_path_index = search_my_index (get_path, getlen);
3684 if (GNUNET_SYSERR == current_path_index )
3687 return GNUNET_SYSERR;
3689 GDS_NEIGHBOURS_send_get_result (&(get_result->key), get_result->type,
3690 &get_path[current_path_index - 1],
3691 &(get_result->querying_peer), putlen, put_path,
3692 getlen, get_path, get_result->expiration_time,
3693 payload, payload_size);
3696 return GNUNET_SYSERR;
3701 * Get the best known next destination (local_dest) among your fingers, friends
3702 * and my identity. In case I was part of trail to reach to some other destination
3703 * (current_dest), then compare current_dest and local_dest, and choose the
3705 * @param final_dest_finger_value Peer closest to this value will be
3706 * @a local_best_known_dest
3707 * @param local_best_known_dest[out] Updated to peer identity which is closest to
3708 * @a final_dest_finger_value.
3709 * @param new_intermediate_trail_id In case @a local_best_known_dest is a finger,
3710 * then the trail id to reach to the finger
3711 * @param is_predecessor Is source peer trying to setup trail to its predecessor
3713 * @param current_dest Peer which should get this message ultimately according
3714 * to the peer which sent me this message. It could be me
3715 * or some other peer. In case it is not me, then I am a part
3716 * of trail to reach to that peer.
3719 static struct GNUNET_PeerIdentity *
3720 get_local_best_known_next_hop (uint64_t final_dest_finger_value,
3721 struct GNUNET_PeerIdentity *local_best_known_dest,
3722 struct GNUNET_HashCode *new_intermediate_trail_id,
3723 struct GNUNET_HashCode intermediate_trail_id,
3724 unsigned int is_predecessor,
3725 struct GNUNET_PeerIdentity *current_dest)
3727 struct GNUNET_PeerIdentity *next_hop_to_local_best_known_dest;
3729 /* Choose a local best known hop among your fingers, friends and you. */
3730 next_hop_to_local_best_known_dest = find_successor (final_dest_finger_value,
3731 local_best_known_dest,
3732 new_intermediate_trail_id,
3735 /* Are we just a part of a trail towards a finger (current_destination)? */
3736 if (0 != (GNUNET_CRYPTO_cmp_peer_identity (&my_identity, current_dest)))
3738 struct GNUNET_PeerIdentity *closest_peer;
3740 /* Select best successor among one found locally and current_destination
3741 * that we got from network.*/
3742 closest_peer = select_closest_peer (local_best_known_dest,
3744 final_dest_finger_value,
3747 /* Is current dest (end point of the trail of which I am a part) closest_peer? */
3748 if (0 == GNUNET_CRYPTO_cmp_peer_identity (current_dest, closest_peer))
3750 struct GNUNET_PeerIdentity *next_hop;
3751 next_hop = GDS_ROUTING_get_next_hop (intermediate_trail_id,
3752 GDS_ROUTING_SRC_TO_DEST);
3753 /* FIXME: Here we found next_hop NULL from routing table, but we still
3754 * have a next_hop from find_successor should we not break and choose that
3756 if (NULL == next_hop)
3758 GNUNET_break_op (0);
3761 next_hop_to_local_best_known_dest = next_hop;
3762 local_best_known_dest = current_dest;
3763 *new_intermediate_trail_id = intermediate_trail_id;
3767 GNUNET_assert (NULL != next_hop_to_local_best_known_dest);
3768 return next_hop_to_local_best_known_dest;
3773 * Core handle for PeerTrailSetupMessage.
3774 * @param cls closure
3775 * @param message message
3776 * @param peer peer identity this notification is about
3777 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
3780 handle_dht_p2p_trail_setup (void *cls, const struct GNUNET_PeerIdentity *peer,
3781 const struct GNUNET_MessageHeader *message)
3783 const struct PeerTrailSetupMessage *trail_setup;
3784 const struct GNUNET_PeerIdentity *trail_peer_list;
3785 struct GNUNET_PeerIdentity *local_best_known_dest;
3786 struct GNUNET_PeerIdentity current_dest;
3787 struct GNUNET_PeerIdentity *next_hop_towards_local_best_known_dest;
3788 struct GNUNET_PeerIdentity next_peer;
3789 struct FriendInfo *target_friend;
3790 struct GNUNET_PeerIdentity source;
3791 uint64_t final_dest_finger_val;
3792 struct GNUNET_HashCode new_intermediate_trail_id;
3793 struct GNUNET_HashCode intermediate_trail_id;
3794 struct GNUNET_HashCode trail_id;
3795 unsigned int is_predecessor;
3796 uint32_t trail_length;
3799 msize = ntohs (message->size);
3800 if (msize < sizeof (struct PeerTrailSetupMessage))
3802 GNUNET_break_op (0);
3806 trail_setup = (const struct PeerTrailSetupMessage *) message;
3807 trail_length = (msize - sizeof (struct PeerTrailSetupMessage))/
3808 sizeof (struct GNUNET_PeerIdentity);
3809 if ((msize - sizeof (struct PeerTrailSetupMessage)) %
3810 sizeof (struct GNUNET_PeerIdentity) != 0)
3812 GNUNET_break_op (0);
3816 trail_peer_list = (const struct GNUNET_PeerIdentity *)&trail_setup[1];
3817 current_dest = trail_setup->best_known_destination;
3818 trail_id = trail_setup->trail_id;
3819 final_dest_finger_val =
3820 GNUNET_ntohll (trail_setup->final_destination_finger_value);
3821 source = trail_setup->source_peer;
3822 is_predecessor = ntohl (trail_setup->is_predecessor);
3823 intermediate_trail_id = trail_setup->intermediate_trail_id;
3825 /* Is my routing table full? */
3826 if (GNUNET_YES == GDS_ROUTING_threshold_reached())
3828 /* As my routing table is full, I can no longer handle any more trail
3830 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer);
3831 GDS_NEIGHBOURS_send_trail_rejection (source, final_dest_finger_val,
3832 my_identity, is_predecessor,
3833 trail_peer_list, trail_length,
3834 trail_id, target_friend,
3835 CONGESTION_TIMEOUT);
3839 local_best_known_dest = GNUNET_new (struct GNUNET_PeerIdentity);
3841 /* Get the next hop to forward the trail setup request. */
3842 next_hop_towards_local_best_known_dest =
3843 get_local_best_known_next_hop (final_dest_finger_val,
3844 local_best_known_dest,
3845 &new_intermediate_trail_id,
3846 intermediate_trail_id,
3850 /* Am I the final destination? */
3851 if (0 == (GNUNET_CRYPTO_cmp_peer_identity (local_best_known_dest,
3854 /* If I was not the source of this message for which now I am destination */
3855 if (0 != GNUNET_CRYPTO_cmp_peer_identity (&source, &my_identity))
3857 GDS_ROUTING_add (trail_id, *peer, my_identity);
3860 if (0 == trail_length)
3861 memcpy (&next_peer, &source, sizeof (struct GNUNET_PeerIdentity));
3863 memcpy (&next_peer, &trail_peer_list[trail_length-1], sizeof (struct GNUNET_PeerIdentity));
3865 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_peer);
3866 GDS_NEIGHBOURS_send_trail_setup_result (source,
3868 target_friend, trail_length,
3870 final_dest_finger_val,
3871 is_predecessor, trail_id);
3875 /* Add yourself to list of peers. */
3876 struct GNUNET_PeerIdentity peer_list[trail_length + 1];
3878 memcpy (peer_list, trail_peer_list,
3879 trail_length * sizeof (struct GNUNET_PeerIdentity));
3880 peer_list[trail_length] = my_identity;
3882 GNUNET_CONTAINER_multipeermap_get (friend_peermap,
3883 next_hop_towards_local_best_known_dest);
3884 GDS_NEIGHBOURS_send_trail_setup (source,
3885 final_dest_finger_val,
3886 *local_best_known_dest,
3887 target_friend, trail_length + 1, peer_list,
3888 is_predecessor, trail_id,
3889 &new_intermediate_trail_id);
3891 GNUNET_free (local_best_known_dest);
3892 GNUNET_free (next_hop_towards_local_best_known_dest);
3897 /* FIXME: here we are calculating my_index and comparing also in this function.
3898 And we are doing it again here in this function. Re factor the code. */
3900 * FIXME: Should we call this function everywhere in all the handle functions
3901 * where we have a trail to verify from or a trail id. something like
3902 * if prev hop is not same then drop the message.
3903 * Check if sender_peer and peer from which we should receive the message are
3904 * same or different.
3905 * @param trail_peer_list List of peers in trail
3906 * @param trail_length Total number of peers in @a trail_peer_list
3907 * @param sender_peer Peer from which we got the message.
3908 * @param finger_identity Finger to which trail is setup. It is not part of trail.
3909 * @return #GNUNET_YES if sender_peer and peer from which we should receive the
3910 * message are different.
3911 * #GNUNET_NO if sender_peer and peer from which we should receive the
3912 * message are different.
3915 is_sender_peer_correct (const struct GNUNET_PeerIdentity *trail_peer_list,
3916 unsigned int trail_length,
3917 const struct GNUNET_PeerIdentity *sender_peer,
3918 struct GNUNET_PeerIdentity finger_identity,
3919 struct GNUNET_PeerIdentity source_peer)
3923 /* I am the source peer. */
3924 if (0 == (GNUNET_CRYPTO_cmp_peer_identity (&source_peer,
3927 /* Is the first element of the trail is sender_peer.*/
3928 if (trail_length > 0)
3930 if (0 != GNUNET_CRYPTO_cmp_peer_identity (&trail_peer_list[0],
3936 /* Is finger the sender peer? */
3937 if (0 != GNUNET_CRYPTO_cmp_peer_identity (sender_peer,
3944 /* Get my current location in the trail. */
3945 my_index = search_my_index (trail_peer_list, trail_length);
3949 /* I am the last element in the trail. */
3950 if ((trail_length - 1) == my_index)
3952 /* Is finger the sender_peer? */
3953 if (0 != GNUNET_CRYPTO_cmp_peer_identity (sender_peer,
3959 /* Is peer after me in trail the sender peer? */
3960 if (0 != GNUNET_CRYPTO_cmp_peer_identity (sender_peer,
3961 &trail_peer_list[my_index + 1]))
3970 * FIXME: we should also add a case where we search if we are present in the trail
3972 * Core handle for p2p trail setup result messages.
3974 * @param message message
3975 * @param peer sender of this message.
3976 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
3979 handle_dht_p2p_trail_setup_result(void *cls, const struct GNUNET_PeerIdentity *peer,
3980 const struct GNUNET_MessageHeader *message)
3982 const struct PeerTrailSetupResultMessage *trail_result;
3983 const struct GNUNET_PeerIdentity *trail_peer_list;
3984 struct GNUNET_PeerIdentity next_hop;
3985 struct FriendInfo *target_friend;
3986 struct GNUNET_PeerIdentity querying_peer;
3987 struct GNUNET_PeerIdentity finger_identity;
3988 uint32_t trail_length;
3989 uint64_t ulitmate_destination_finger_value;
3990 uint32_t is_predecessor;
3991 struct GNUNET_HashCode trail_id;
3995 msize = ntohs (message->size);
3996 if (msize < sizeof (struct PeerTrailSetupResultMessage))
3998 GNUNET_break_op (0);
4002 trail_result = (const struct PeerTrailSetupResultMessage *) message;
4003 trail_length = (msize - sizeof (struct PeerTrailSetupResultMessage))/
4004 sizeof (struct GNUNET_PeerIdentity);
4005 if ((msize - sizeof (struct PeerTrailSetupResultMessage)) %
4006 sizeof (struct GNUNET_PeerIdentity) != 0)
4008 GNUNET_break_op (0);
4012 is_predecessor = htonl (trail_result->is_predecessor);
4013 querying_peer = trail_result->querying_peer;
4014 finger_identity = trail_result->finger_identity;
4015 trail_id = trail_result->trail_id;
4016 trail_peer_list = (const struct GNUNET_PeerIdentity *) &trail_result[1];
4017 ulitmate_destination_finger_value =
4018 GNUNET_ntohll (trail_result->ulitmate_destination_finger_value);
4020 /* FIXME: here we are calculating my_index and comparing also in this function.
4021 And we are doing it again here in this function. Re factor the code. */
4022 /* Ensure that sender peer is the peer from which we were expecting the message. */
4023 if (GNUNET_NO == is_sender_peer_correct (trail_peer_list,
4025 peer, finger_identity, querying_peer))
4027 GNUNET_break_op (0);
4028 return GNUNET_SYSERR;
4031 /* Am I the one who initiated the query? */
4032 if (0 == (GNUNET_CRYPTO_cmp_peer_identity (&querying_peer,
4035 /* If I am not my own finger identity, then add routing table entry. */
4036 if (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &finger_identity))
4038 GDS_ROUTING_add (trail_id, my_identity, *peer);
4041 finger_table_add (finger_identity, trail_peer_list,
4042 trail_length, ulitmate_destination_finger_value,
4043 is_predecessor, trail_id);
4047 /* Get my location in the trail. */
4048 my_index = search_my_index(trail_peer_list, trail_length);
4052 return GNUNET_SYSERR;
4056 next_hop = trail_result->querying_peer;
4058 next_hop = trail_peer_list[my_index - 1];
4060 /* If the querying_peer is its own finger, then don't add an entry in routing
4061 * table as querying peer will discard the trail. */
4062 if (0 != (GNUNET_CRYPTO_cmp_peer_identity (&(trail_result->querying_peer),
4063 &(trail_result->finger_identity))))
4065 GDS_ROUTING_add (trail_id, next_hop, *peer);
4068 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
4069 GDS_NEIGHBOURS_send_trail_setup_result (querying_peer, finger_identity,
4070 target_friend, trail_length, trail_peer_list,
4072 ulitmate_destination_finger_value,
4080 * @param trail Trail to be inverted
4081 * @param trail_length Total number of peers in the trail.
4082 * @return Updated trail
4084 static struct GNUNET_PeerIdentity *
4085 invert_trail (const struct GNUNET_PeerIdentity *trail,
4086 unsigned int trail_length)
4090 struct GNUNET_PeerIdentity *inverted_trail;
4092 inverted_trail = GNUNET_malloc (sizeof(struct GNUNET_PeerIdentity) *
4095 j = trail_length - 1;
4096 while (i < trail_length)
4098 inverted_trail[i] = trail[j];
4102 return inverted_trail;
4107 * Return the shortest trail to reach from me to my_predecessor.
4108 * @param my_predecessor my current predecessor.
4109 * @param current_trail Trail from source to me.
4110 * @param current_trail_length Total number of peers in @a current_trail
4111 * @param trail_length [out] Total number of peers in selected trail.
4112 * @return Updated trail from source peer to my_predecessor.
4114 static struct GNUNET_PeerIdentity *
4115 trail_source_to_my_predecessor (const struct GNUNET_PeerIdentity *current_trail,
4116 unsigned int current_trail_length,
4117 unsigned int *trail_length)
4119 struct GNUNET_PeerIdentity *trail_me_to_predecessor;
4120 struct Trail *trail;
4121 struct Trail_Element *trail_element;
4122 struct FingerInfo *my_predecessor;
4124 unsigned int shortest_trail_length = 0;
4125 unsigned int trail_index = 0;
4127 my_predecessor = &finger_table[PREDECESSOR_FINGER_ID];
4129 GNUNET_assert (GNUNET_YES == my_predecessor->is_present);
4131 //if my_predecessor is a friend then don't send back any trail. as
4132 // there is no trail.
4135 /* Choose the shortest path from me to my predecessor. */
4136 for (i = 0; i < my_predecessor->trails_count; i++)
4138 trail = &my_predecessor->trail_list[i];
4139 if (trail->trail_length > shortest_trail_length)
4141 shortest_trail_length = trail->trail_length;
4145 *trail_length = shortest_trail_length;
4146 trail_me_to_predecessor = GNUNET_malloc (sizeof (struct GNUNET_PeerIdentity)
4149 /* Copy the selected trail and send this trail to calling function. */
4151 trail = &my_predecessor->trail_list[trail_index];
4152 trail_element = trail->trail_head;
4153 while ( i < shortest_trail_length)
4155 trail_me_to_predecessor[i] = trail_element->peer;
4157 trail_element = trail_element->next;
4160 return trail_me_to_predecessor;
4165 * FIXME In case predecessor is a friend then do we add it in routing table.
4166 * if not then check the logic of trail teardown in case we compress the trail
4167 * such that friend is finger. then do we remove the entry from end points or
4168 * not. Ideally we should remove the entries from end point.
4169 * Add finger as your predecessor. To add, first generate a new trail id, invert
4170 * the trail to get the trail from me to finger, add an entry in your routing
4171 * table, send add trail message to peers which are part of trail from me to
4172 * finger and add finger in finger table.
4175 * @param trail_length
4178 update_predecessor (struct GNUNET_PeerIdentity finger,
4179 struct GNUNET_PeerIdentity *trail,
4180 unsigned int trail_length)
4182 struct GNUNET_HashCode trail_to_new_predecessor_id;
4183 struct GNUNET_PeerIdentity *trail_to_new_predecessor;
4184 struct FriendInfo *target_friend;
4186 /* Generate trail id for trail from me to new predecessor = finger. */
4187 GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_STRONG,
4188 &trail_to_new_predecessor_id,
4189 sizeof (trail_to_new_predecessor_id));
4191 /* Invert the trail from finger to me to get the trail from me to finger. */
4192 if (trail_length == 0)
4193 trail_to_new_predecessor = NULL;
4195 if (trail_length > 0)
4197 trail_to_new_predecessor = invert_trail (trail, trail_length);
4198 /* Add an entry in your routing table. */
4199 GDS_ROUTING_add (trail_to_new_predecessor_id,
4200 trail_to_new_predecessor[trail_length - 1],
4204 GNUNET_CONTAINER_multipeermap_get (friend_peermap,
4205 &trail_to_new_predecessor[trail_length - 1]);
4207 // Before sending the trail may be you need to compress it. And in case
4208 // it was a friend how did we got the trail. ??
4210 /* Add entry in routing table of all peers that are part of trail from me
4213 GDS_NEIGHBOURS_send_add_trail (my_identity,
4215 trail_to_new_predecessor_id,
4216 trail_to_new_predecessor,
4221 add_new_finger (finger, trail_to_new_predecessor, trail_length,
4222 trail_to_new_predecessor_id, PREDECESSOR_FINGER_ID);
4223 GNUNET_free_non_null (trail_to_new_predecessor);
4227 /* 3. In case you are successor, then
4228 * 3.1 check if you have a predecessor
4229 * 3.2 if no predecessor, then add the source of this message as your
4230 * predecessor. To add, first you should generate a new trail id,
4231 * invert the trail, send add trail message across new trail, add
4232 * an entry in finger table. Now, destination also have routing
4233 * table entry so add in your routing table also.
4234 * 3.3 If its closer than existing one, then do everything in step 1 and
4235 * free existing finger.
4236 * 3.3 If its same as the old one, then do nothing.
4237 * 3.4 if its not same as old one, and between source and old one, old one
4238 * is the correct predecessor, then construct a trail from source
4239 * to your old successor. scan the trail to remove duplicate entries.
4240 * 4. send verify successor result, with trail id of trail from source to
4241 * me. And also send the new trail from source to reach to its probable
4244 * 1. this function is called from both verify and notify.
4245 * 2. so write in a way that it is used in both.
4248 * Check if you have a predecessor.
4249 * 1. if no predecessor, then add finger as your predecessor. To add, first
4250 * generate a new trail id, invert the trail to get the trail from me to finger,
4251 * add an entry in your routing table, send add trail message to peers which
4252 * are part of trail from me to finger and add finger in finger table.
4253 * 2. If there is a predecessor, then compare existing one and finger.
4254 * 2.1 If finger is correct predecessor, then remove current_predecessor. And
4255 * do everything in step 1 to add finger into finger table.
4256 * 2.2 If current_predecessor is correct predecessor, the construct a trail from
4257 * finger to current_predecessor.
4260 * @param trail_length
4264 compare_and_update_predecessor (struct GNUNET_PeerIdentity finger,
4265 struct GNUNET_PeerIdentity *trail,
4266 unsigned int trail_length)
4268 struct FingerInfo *current_predecessor;
4269 struct GNUNET_PeerIdentity *closest_peer;
4270 uint64_t predecessor_value;
4272 current_predecessor = &finger_table[PREDECESSOR_FINGER_ID];
4274 GNUNET_assert (0 != GNUNET_CRYPTO_cmp_peer_identity (&finger, &my_identity));
4276 /* No predecessor. Add finger as your predecessor. */
4277 if (GNUNET_NO == current_predecessor->is_present)
4279 update_predecessor (finger, trail, trail_length);
4283 predecessor_value = compute_finger_identity_value (PREDECESSOR_FINGER_ID);
4284 closest_peer = select_closest_peer (&finger,
4285 ¤t_predecessor->finger_identity,
4286 predecessor_value, PREDECESSOR_FINGER_ID);
4288 /* Finger is the closest predecessor. Remove the existing one and add the new
4290 if (0 == GNUNET_CRYPTO_cmp_peer_identity (closest_peer, &finger))
4292 remove_existing_finger (current_predecessor, PREDECESSOR_FINGER_ID);
4293 update_predecessor (finger, trail, trail_length);
4302 * FIXME: if i have no predecessor and I get a new predecessor but the first
4303 * friend to reach to that hop is congested then?
4304 * 1. check if you are the successor or not.
4305 * 2. if not then get the next hop from routing table, and pass the message,
4306 * 3. In case you are successor, then
4307 * 3.1 check if you have a predecessor
4308 * 3.2 if no predecessor, then add the source of this message as your
4309 * predecessor. To add, first you should generate a new trail id,
4310 * invert the trail, send add trail message across new trail, add
4311 * an entry in finger table. Now, destination also have routing
4312 * table entry so add in your routing table also.
4313 * 3.3 If its closer than existing one, then do everything in step 1 and
4314 * free existing finger.
4315 * 3.3 If its same as the old one, then do nothing.
4316 * 3.4 if its not same as old one, and between source and old one, old one
4317 * is the correct predecessor, then choose the shortest path to reach
4318 * from you to your predecessor. Pass this trail to source of this message.
4319 * It is the responsibility of source peer to scan the trail to reach to
4320 * its new probable successor.
4321 * 4. send verify successor result, with trail id of trail from source to
4322 * me. And also send the trail from me to reach to my predecessor, if
4323 * my_predecessor != source.
4325 * Core handle for p2p verify successor messages.
4326 * @param cls closure
4327 * @param message message
4328 * @param peer peer identity this notification is about
4329 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
4332 handle_dht_p2p_verify_successor(void *cls,
4333 const struct GNUNET_PeerIdentity *peer,
4334 const struct GNUNET_MessageHeader *message)
4336 const struct PeerVerifySuccessorMessage *vsm;
4337 struct GNUNET_HashCode trail_id;
4338 struct GNUNET_PeerIdentity successor;
4339 struct GNUNET_PeerIdentity source_peer;
4340 struct GNUNET_PeerIdentity *trail;
4341 struct GNUNET_PeerIdentity *next_hop;
4342 struct GNUNET_PeerIdentity *trail_to_predecessor;
4343 struct FingerInfo *current_predecessor;
4344 struct FriendInfo *target_friend;
4345 unsigned int trail_to_predecessor_length;
4347 unsigned int trail_length;
4349 msize = ntohs (message->size);
4351 /* Here we pass trail to reach from source to successor, and in case successor
4352 * does not have any predecessor, then we will add source as my predecessor.
4353 * So we pass the trail along with trail id. */
4354 if (msize < sizeof (struct PeerVerifySuccessorMessage))
4356 GNUNET_break_op (0);
4360 vsm = (const struct PeerVerifySuccessorMessage *) message;
4361 trail_length = (msize - sizeof (struct PeerVerifySuccessorMessage))/
4362 sizeof (struct GNUNET_PeerIdentity);
4363 if ((msize - sizeof (struct PeerVerifySuccessorMessage)) %
4364 sizeof (struct GNUNET_PeerIdentity) != 0)
4366 GNUNET_break_op (0);
4370 trail_id = vsm->trail_id;
4371 source_peer = vsm->source_peer;
4372 successor = vsm->successor;
4373 trail = (struct GNUNET_PeerIdentity *)&vsm[1];
4375 //GDS_ROUTING_test_print(); //FIXME REMOVE AFTERWARDS.
4376 //FIXME: we can have a check if peer is correct peer which should have
4377 // sent this message. use same function is_sender_peer_correct
4378 // but specify direction so that the function can be used in other functions
4381 /* I am not the successor of source_peer. Pass the message to next_hop on
4383 if(0 != (GNUNET_CRYPTO_cmp_peer_identity (&successor, &my_identity)))
4385 next_hop = GDS_ROUTING_get_next_hop (trail_id, GDS_ROUTING_SRC_TO_DEST);
4386 if (NULL == next_hop)
4389 return GNUNET_SYSERR;
4391 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
4393 GDS_NEIGHBOURS_send_verify_successor_message (source_peer, successor,
4394 trail_id, trail, trail_length,
4399 /* I am the destination of this message. */
4401 /* Check if the source_peer could be our predecessor and if yes then update
4403 compare_and_update_predecessor (source_peer, trail, trail_length);
4405 current_predecessor = &finger_table[PREDECESSOR_FINGER_ID];
4407 /* Is source of this message my predecessor. */
4408 if (0 == (GNUNET_CRYPTO_cmp_peer_identity (¤t_predecessor->finger_identity,
4411 trail_to_predecessor = NULL;
4412 trail_to_predecessor_length = 0;
4416 if (NULL == (GNUNET_CONTAINER_multipeermap_get (friend_peermap,
4417 ¤t_predecessor->finger_identity)))
4419 /* Only if current predecessor is not a friend, we have a trail to reach
4420 to it. Only in that case we pass the trail. */
4421 trail_to_predecessor =
4422 trail_source_to_my_predecessor (trail, trail_length,
4423 &trail_to_predecessor_length);
4427 trail_to_predecessor = NULL;
4428 trail_to_predecessor_length = 0;
4431 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer);
4432 GDS_NEIGHBOURS_send_verify_successor_result (source_peer, my_identity,
4433 current_predecessor->finger_identity,
4434 trail_id, trail_to_predecessor,
4435 trail_to_predecessor_length,
4436 GDS_ROUTING_DEST_TO_SRC,
4438 GNUNET_free_non_null (trail_to_predecessor);
4444 * Construct the trail from me to probable successor that goes through current
4445 * successor. Scan this trail to check if you can shortcut the trail somehow.
4446 * In case we can shortcut the trail, don't send trail compression as we don't
4447 * have any entry in routing table.
4448 * @param current_successor
4449 * @param probable_successor
4450 * @param trail_from_curr_to_probable_successor
4451 * @param trail_from_curr_to_probable_successor_length
4452 * @param trail_to_new_successor_length
4455 static struct GNUNET_PeerIdentity *
4456 get_trail_to_new_successor (struct FingerInfo *current_successor,
4457 struct GNUNET_PeerIdentity probable_successor,
4458 const struct GNUNET_PeerIdentity *trail,
4459 unsigned int trail_length,
4460 unsigned int *trail_to_new_successor_length)
4462 struct GNUNET_PeerIdentity *trail_to_new_successor;
4464 /* If the probable successor is a friend, then we don't need to have a trail
4466 if (NULL != GNUNET_CONTAINER_multipeermap_get (friend_peermap,
4467 &probable_successor))
4469 trail_to_new_successor = NULL;
4470 *trail_to_new_successor_length = 0;
4471 return trail_to_new_successor;
4475 * FIXME: can we some how use the select_finger_trail here??
4476 * complete this logic.
4477 * 1. Choose the shortest trail to reach to current successor.
4478 * 2. append the trail with the current trail
4479 * 3. scan the trail for duplicate elements
4480 * 4. scan the trail for friend
4481 * 5. get the shortest trail.
4482 * 6. send back the trail.
4489 * Compare probable successor and current successor.
4490 * If the probable successor is the correct successor, then construct the trail
4491 * from me to probable successor that goes through current successor. Scan this
4492 * trail to check if you can shortcut the trail somehow. In case we can short
4493 * cut the trail, don't send trail compression as we don't have any entry in
4495 * Once you have scanned trail, then add an entry in finger table.
4496 * Add an entry in routing table (Only if new successor is NOT a friend).
4497 * @param probable_successor Peer which could be our successor
4498 * @param trail_from_curr_to_probable_successor Trail from current successor
4499 * to probable successor, NOT
4501 * @param trail_from_curr_to_probable_successor_length Total number of peers
4502 * in @a trail_from_curr_to_probable_successor
4505 compare_and_update_successor (struct GNUNET_PeerIdentity probable_successor,
4506 const struct GNUNET_PeerIdentity *trail_from_curr_to_probable_successor,
4507 unsigned int trail_from_curr_to_probable_successor_length)
4509 struct GNUNET_PeerIdentity *closest_peer;
4510 struct GNUNET_PeerIdentity *trail_to_new_successor;
4511 struct GNUNET_HashCode trail_id;
4512 unsigned int trail_to_new_successor_length;
4513 uint64_t successor_value;
4514 struct FingerInfo *current_successor;
4515 struct FriendInfo *target_friend;
4517 current_successor = &finger_table[0];
4518 GNUNET_assert (GNUNET_YES == current_successor->is_present);
4520 /* Compute the 64 bit value of successor identity. We need this as we need to
4521 * find the closest peer w.r.t this value.*/
4522 successor_value = compute_finger_identity_value (0);
4523 closest_peer = select_closest_peer (¤t_successor->finger_identity,
4524 &probable_successor,
4525 successor_value, 0);
4527 /* If the current_successor is the closest one, then exit. */
4528 if (0 == GNUNET_CRYPTO_cmp_peer_identity (closest_peer,
4529 ¤t_successor->finger_identity))
4532 /* probable successor is the closest_peer. */
4534 /* Get the trail to reach to your new successor. */
4535 trail_to_new_successor = get_trail_to_new_successor (current_successor,
4537 trail_from_curr_to_probable_successor,
4538 trail_from_curr_to_probable_successor_length,
4539 &trail_to_new_successor_length);
4540 /* Remove the existing successor. */
4541 remove_existing_finger (current_successor, 0);
4543 /* Generate a new trail id to reach to your new successor. */
4544 GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_STRONG,
4545 &trail_id, sizeof (trail_id));
4546 add_new_finger (probable_successor, trail_to_new_successor,
4547 trail_to_new_successor_length, trail_id, 0);
4549 /* If probable successor is not a friend, then add an entry in your own
4551 if (trail_to_new_successor_length > 0)
4553 GDS_ROUTING_add (trail_id, my_identity, trail_to_new_successor[0]);
4554 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
4555 &trail_to_new_successor[0]);
4559 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap,
4560 &probable_successor);
4563 GDS_NEIGHBOURS_send_notify_new_successor (my_identity, probable_successor,
4564 trail_from_curr_to_probable_successor,
4565 trail_from_curr_to_probable_successor_length,
4573 * 1. If you are not the querying peer then pass on the message,
4574 * 2. If you are querying peer, then
4575 * 2.1 is new successor same as old one
4576 * 2.1.1 if yes then do noting
4577 * 2.1.2 if no then you need to notify the new one about your existence,
4578 * 2.1.2,1 also you need to remove the older successor, remove entry
4579 * from finger table, send trail teardown message across all the trail
4580 * of older successor. Call notify new successor with new trail id
4581 * and new trail to reach it.
4582 * Core handle for p2p verify successor result messages.
4583 * @param cls closure
4584 * @param message message
4585 * @param peer peer identity this notification is about
4586 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
4589 handle_dht_p2p_verify_successor_result(void *cls,
4590 const struct GNUNET_PeerIdentity *peer,
4591 const struct GNUNET_MessageHeader *message)
4593 const struct PeerVerifySuccessorResultMessage *vsrm;
4594 enum GDS_ROUTING_trail_direction trail_direction;
4595 struct GNUNET_PeerIdentity querying_peer;
4596 struct GNUNET_HashCode trail_id;
4597 struct GNUNET_PeerIdentity *next_hop;
4598 struct FriendInfo *target_friend;
4599 struct GNUNET_PeerIdentity probable_successor;
4600 const struct GNUNET_PeerIdentity *trail;
4601 unsigned int trail_length;
4604 msize = ntohs (message->size);
4605 /* We send a trail to reach from old successor to new successor, if
4606 * old_successor != new_successor.*/
4607 if (msize < sizeof (struct PeerVerifySuccessorResultMessage))
4609 GNUNET_break_op (0);
4613 vsrm = (const struct PeerVerifySuccessorResultMessage *) message;
4614 trail_length = (msize - sizeof (struct PeerVerifySuccessorResultMessage))/
4615 sizeof (struct GNUNET_PeerIdentity);
4617 if ((msize - sizeof (struct PeerVerifySuccessorResultMessage)) %
4618 sizeof (struct GNUNET_PeerIdentity) != 0)
4620 GNUNET_break_op (0);
4624 trail = (const struct GNUNET_PeerIdentity *) &vsrm[1];
4625 querying_peer = vsrm->querying_peer;
4626 trail_direction = ntohl (vsrm->trail_direction);
4627 trail_id = vsrm->trail_id;
4628 probable_successor = vsrm->probable_successor;
4630 //FIXME: add a check to ensure that peer from which you got the message is
4632 /* I am the querying_peer. */
4633 if(0 == (GNUNET_CRYPTO_cmp_peer_identity (&querying_peer, &my_identity)))
4635 compare_and_update_successor (probable_successor, trail, trail_length);
4639 /*If you are not the querying peer then pass on the message */
4640 GNUNET_assert (NULL != (next_hop =
4641 GDS_ROUTING_get_next_hop (trail_id, trail_direction)));
4642 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
4643 GDS_NEIGHBOURS_send_verify_successor_result (querying_peer,
4644 vsrm->current_successor,
4645 probable_successor, trail_id,
4648 trail_direction, target_friend);
4654 * Add entry in your routing table if source of the message is not a friend.
4655 * Irrespective if destination peer accepts source peer as predecessor or not,
4656 * we need to add an entry. So, that in next round to verify successor, source
4657 * is able to reach to its successor.
4658 * Check if you are the new successor of this message
4659 * 1. If yes the call function compare_and_update_successor(). This function
4660 * checks if source is real predecessor or not and take action accordingly.
4661 * 2. If not then find the next hop to find the message from the trail that
4662 * you got from the message and pass on the message.
4663 * Core handle for p2p notify new successor messages.
4664 * @param cls closure
4665 * @param message message
4666 * @param peer peer identity this notification is about
4667 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
4670 handle_dht_p2p_notify_new_successor(void *cls,
4671 const struct GNUNET_PeerIdentity *peer,
4672 const struct GNUNET_MessageHeader *message)
4674 const struct PeerNotifyNewSuccessorMessage *nsm;
4675 struct GNUNET_PeerIdentity *trail;
4676 struct GNUNET_PeerIdentity source;
4677 struct GNUNET_PeerIdentity new_successor;
4678 struct GNUNET_HashCode trail_id;
4679 struct GNUNET_PeerIdentity next_hop;
4680 struct FriendInfo *target_friend;
4683 uint32_t trail_length;
4685 msize = ntohs (message->size);
4686 /* We have the trail to reach from source to new successor. */
4687 if (msize < sizeof (struct PeerNotifyNewSuccessorMessage))
4689 GNUNET_break_op (0);
4693 nsm = (const struct PeerNotifyNewSuccessorMessage *) message;
4694 trail_length = (msize - sizeof (struct PeerNotifyNewSuccessorMessage))/
4695 sizeof (struct GNUNET_PeerIdentity);
4696 if ((msize - sizeof (struct PeerTrailRejectionMessage)) %
4697 sizeof (struct GNUNET_PeerIdentity) != 0)
4699 GNUNET_break_op (0);
4703 trail = (struct GNUNET_PeerIdentity *) &nsm[1];
4704 source = nsm->source_peer;
4705 new_successor = nsm->new_successor;
4706 trail_id = nsm->trail_id;
4708 //FIXME: add a check to make sure peer is correct.
4710 /* I am the new_successor to source_peer. */
4711 if ( 0 == GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &new_successor))
4713 /* Add an entry in routing table only if new predecessor is not a friend. */
4714 if (NULL == GNUNET_CONTAINER_multipeermap_get(friend_peermap, &source))
4716 GDS_ROUTING_add (trail_id, *peer, my_identity);
4718 compare_and_update_predecessor (source, trail, trail_length);
4722 /* I am part of trail to reach to successor. */
4723 my_index = search_my_index (trail, trail_length);
4726 GNUNET_break_op (0);
4727 return GNUNET_SYSERR;
4729 if (trail_length == my_index)
4730 next_hop = new_successor;
4732 next_hop = trail[my_index + 1];
4734 /* Add an entry in routing table for trail from source to its new successor. */
4735 GNUNET_assert (GNUNET_OK == GDS_ROUTING_add (trail_id, *peer, next_hop));
4736 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
4737 GDS_NEIGHBOURS_send_notify_new_successor (source, new_successor, trail,
4739 trail_id, target_friend);
4746 * 1. Set the congestion timeout for the friend which is congested and sent
4748 * 2. Check if you were the source of this message
4749 * 2.1 If yes then exit. find_finger_trail_task is scheduled periodically.
4750 * So, we will eventually send a new request to setup trail to finger.
4751 * 2. Check if you can handle more trails through you. (Routing table space)
4752 * 2.1 If not then you are congested. Set your congestion time and pass this
4753 * message to peer before you in the trail setup so far.
4754 * 2.2 If yes, the call find_successor(). It will give you the next hop to
4755 * pass this message.
4756 * 2.2.1 If you are the final destination, then send back the trail setup
4758 * 2.2.2 If you are not the final dest, then send trail setup message to
4760 * Core handler for P2P trail rejection message
4761 * @param cls closure
4762 * @param message message
4763 * @param peer peer identity this notification is about
4764 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
4767 handle_dht_p2p_trail_setup_rejection (void *cls,
4768 const struct GNUNET_PeerIdentity *peer,
4769 const struct GNUNET_MessageHeader *message)
4771 const struct PeerTrailRejectionMessage *trail_rejection;
4772 unsigned int trail_length;
4773 const struct GNUNET_PeerIdentity *trail_peer_list;
4774 struct FriendInfo *target_friend;
4775 struct GNUNET_TIME_Relative congestion_timeout;
4776 struct GNUNET_HashCode trail_id;
4777 struct GNUNET_PeerIdentity next_destination;
4778 struct GNUNET_HashCode new_intermediate_trail_id;
4779 struct GNUNET_PeerIdentity next_peer;
4780 struct GNUNET_PeerIdentity source;
4781 struct GNUNET_PeerIdentity *next_hop;
4782 uint64_t ultimate_destination_finger_value;
4783 unsigned int is_predecessor;
4786 msize = ntohs (message->size);
4787 /* We are passing the trail setup so far. */
4788 if (msize < sizeof (struct PeerTrailRejectionMessage))
4790 GNUNET_break_op (0);
4794 trail_rejection = (const struct PeerTrailRejectionMessage *) message;
4795 trail_length = (msize - sizeof (struct PeerTrailRejectionMessage))/
4796 sizeof (struct GNUNET_PeerIdentity);
4797 if ((msize - sizeof (struct PeerTrailRejectionMessage)) %
4798 sizeof (struct GNUNET_PeerIdentity) != 0)
4800 GNUNET_break_op (0);
4804 trail_peer_list = (const struct GNUNET_PeerIdentity *)&trail_rejection[1];
4805 is_predecessor = ntohl (trail_rejection->is_predecessor);
4806 congestion_timeout = trail_rejection->congestion_time;
4807 source = trail_rejection->source_peer;
4808 trail_id = trail_rejection->trail_id;
4809 ultimate_destination_finger_value =
4810 GNUNET_ntohll (trail_rejection->ultimate_destination_finger_value);
4812 /* First set the congestion time of the friend that sent you this message. */
4813 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer);
4814 target_friend->congestion_timestamp =
4815 GNUNET_TIME_absolute_add (GNUNET_TIME_absolute_get(),
4816 congestion_timeout);
4818 /* I am the source peer which wants to setup the trail. Do nothing.
4819 * send_find_finger_trail_task is scheduled periodically.*/
4820 if(0 == (GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &source)))
4823 /* If I am congested then pass this message to peer before me in trail. */
4824 if(GNUNET_YES == GDS_ROUTING_threshold_reached())
4826 struct GNUNET_PeerIdentity *new_trail;
4827 unsigned int new_trail_length;
4829 /* Remove yourself from the trail setup so far. */
4830 if (trail_length == 1)
4833 new_trail_length = 0;
4838 memcpy (&next_hop , &trail_peer_list[trail_length - 2],
4839 sizeof (struct GNUNET_PeerIdentity));
4841 /* Remove myself from the trail. */
4842 new_trail_length = trail_length -1;
4843 new_trail = GNUNET_malloc (new_trail_length * sizeof (struct GNUNET_PeerIdentity));
4844 memcpy (new_trail, trail_peer_list, new_trail_length * sizeof (struct GNUNET_PeerIdentity));
4847 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
4848 GDS_NEIGHBOURS_send_trail_rejection (source,
4849 ultimate_destination_finger_value,
4850 my_identity, is_predecessor,
4851 new_trail,new_trail_length,trail_id,
4852 target_friend, CONGESTION_TIMEOUT);
4853 GNUNET_free (new_trail);
4857 /* Look for next_hop to pass the trail setup message */
4858 next_hop = find_successor (ultimate_destination_finger_value,
4860 &new_intermediate_trail_id,
4863 /* Am I the final destination? */
4864 if (0 == (GNUNET_CRYPTO_cmp_peer_identity (next_hop, &my_identity)))
4866 /* Add an entry in routing table only
4867 * 1. If I am not the original source which sent the request for trail setup
4868 * 2. If trail length > 0.
4869 * NOTE: In case trail length > 0 and source is my friend, then also I add
4870 * an entry in routing table,as we will send a trail compression message
4873 if ((0 != GNUNET_CRYPTO_cmp_peer_identity (&source, &my_identity)) ||
4875 GNUNET_assert (GNUNET_YES == GDS_ROUTING_add (trail_id, *peer, my_identity));
4877 if (0 == trail_length)
4880 next_peer = trail_peer_list[trail_length-1];
4882 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_peer);
4883 GDS_NEIGHBOURS_send_trail_setup_result (source,
4885 target_friend, trail_length,
4888 ultimate_destination_finger_value,
4893 struct GNUNET_PeerIdentity peer_list[trail_length + 1];
4895 memcpy (peer_list, trail_peer_list, trail_length * sizeof (struct GNUNET_PeerIdentity));
4896 peer_list[trail_length] = my_identity;
4898 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop);
4899 GDS_NEIGHBOURS_send_trail_setup (source,
4900 ultimate_destination_finger_value,
4902 target_friend, trail_length + 1, peer_list,
4903 is_predecessor, trail_id,
4904 &new_intermediate_trail_id);
4906 GNUNET_free (next_hop);
4912 * If you are the new first friend, then update prev hop to source of this message
4913 * else get the next hop and pass this message forward to ultimately reach
4915 * Core handle for p2p trail tear compression messages.
4916 * @param cls closure
4917 * @param message message
4918 * @param peer peer identity this notification is about
4919 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
4922 handle_dht_p2p_trail_compression (void *cls, const struct GNUNET_PeerIdentity *peer,
4923 const struct GNUNET_MessageHeader *message)
4925 const struct PeerTrailCompressionMessage *trail_compression;
4926 struct GNUNET_PeerIdentity *next_hop;
4927 struct FriendInfo *target_friend;
4928 struct GNUNET_HashCode trail_id;
4931 msize = ntohs (message->size);
4932 /* Here we pass only the trail id. */
4933 if (msize != sizeof (struct PeerTrailCompressionMessage))
4935 GNUNET_break_op (0);
4939 trail_compression = (const struct PeerTrailCompressionMessage *) message;
4940 trail_id = trail_compression->trail_id;
4941 //FIXME: again check if peer is the correct peer. same logic as
4942 //trail teardown make a generic function.
4944 /* Am I the new first friend to reach to finger of this trail. */
4945 if (0 == (GNUNET_CRYPTO_cmp_peer_identity (&(trail_compression->new_first_friend),
4948 /* Update your prev hop to source of this message. */
4949 GDS_ROUTING_update_trail_prev_hop (trail_id,
4950 trail_compression->source_peer);
4954 /* Pass the message to next hop to finally reach to new_first_friend. */
4955 next_hop = GDS_ROUTING_get_next_hop (trail_id, GDS_ROUTING_SRC_TO_DEST);
4956 if (NULL == next_hop)
4962 GNUNET_assert (NULL != (target_friend =
4963 GNUNET_CONTAINER_multipeermap_get (friend_peermap, next_hop)));
4964 GDS_NEIGHBOURS_send_trail_compression (trail_compression->source_peer,
4966 trail_compression->new_first_friend,
4973 * Remove entry from your own routing table and pass the message to next
4974 * peer in the trail.
4975 * Core handler for trail teardown message.
4976 * @param cls closure
4977 * @param message message
4978 * @param peer sender of this messsage.
4979 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
4982 handle_dht_p2p_trail_teardown (void *cls, const struct GNUNET_PeerIdentity *peer,
4983 const struct GNUNET_MessageHeader *message)
4985 const struct PeerTrailTearDownMessage *trail_teardown;
4986 enum GDS_ROUTING_trail_direction trail_direction;
4987 struct GNUNET_HashCode trail_id;
4988 struct GNUNET_PeerIdentity *prev_hop;
4989 struct GNUNET_PeerIdentity *next_hop;
4991 msize = ntohs (message->size);
4993 /* Here we pass only the trail id. */
4994 if (msize != sizeof (struct PeerTrailTearDownMessage))
4996 GNUNET_break_op (0);
5000 trail_teardown = (const struct PeerTrailTearDownMessage *) message;
5001 trail_direction = ntohl (trail_teardown->trail_direction);
5002 trail_id = trail_teardown->trail_id;
5004 /* Check if peer is the real peer from which we should get this message.*/
5005 /* Get the prev_hop for this trail by getting the next hop in opposite direction. */
5006 /* FIXME: is using negation of trail direction correct. */
5007 GNUNET_assert (NULL != (prev_hop =
5008 GDS_ROUTING_get_next_hop (trail_id, !trail_direction)));
5009 if (0 != GNUNET_CRYPTO_cmp_peer_identity (prev_hop, peer))
5012 return GNUNET_SYSERR;
5015 next_hop = GDS_ROUTING_get_next_hop (trail_id, trail_direction);
5016 if (NULL == next_hop)
5019 return GNUNET_SYSERR;
5022 GNUNET_assert (GNUNET_YES == GDS_ROUTING_remove_trail (trail_id));
5024 /* If next_hop is my_identity, it means I am the final destination. */
5025 if (0 == GNUNET_CRYPTO_cmp_peer_identity (next_hop, &my_identity))
5028 /* If not final destination, then send a trail teardown message to next hop.*/
5029 GDS_NEIGHBOURS_send_trail_teardown (trail_id, trail_direction, next_hop);
5030 //GNUNET_free_non_null (next_hop);
5036 * Add an entry in your routing table. If you are destination of this message
5037 * then next_hop in routing table should be your own identity. If you are NOT
5038 * destination, then get the next hop and forward message to it.
5039 * Core handle for p2p add trail message.
5040 * @param cls closure
5041 * @param message message
5042 * @param peer peer identity this notification is about
5043 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
5046 handle_dht_p2p_add_trail (void *cls, const struct GNUNET_PeerIdentity *peer,
5047 const struct GNUNET_MessageHeader *message)
5049 const struct PeerAddTrailMessage *add_trail;
5050 const struct GNUNET_PeerIdentity *trail;
5051 struct GNUNET_HashCode trail_id;
5052 struct GNUNET_PeerIdentity destination_peer;
5053 struct GNUNET_PeerIdentity source_peer;
5054 struct GNUNET_PeerIdentity next_hop;
5055 unsigned int trail_length;
5056 unsigned int my_index;
5059 msize = ntohs (message->size);
5060 /* In this message we pass the whole trail from source to destination as we
5061 * are adding that trail.*/
5062 if (msize < sizeof (struct PeerAddTrailMessage))
5064 GNUNET_break_op (0);
5068 add_trail = (const struct PeerAddTrailMessage *) message;
5069 trail_length = (msize - sizeof (struct PeerAddTrailMessage))/
5070 sizeof (struct GNUNET_PeerIdentity);
5071 if ((msize - sizeof (struct PeerAddTrailMessage)) %
5072 sizeof (struct GNUNET_PeerIdentity) != 0)
5074 GNUNET_break_op (0);
5078 trail = (const struct GNUNET_PeerIdentity *)&add_trail[1];
5079 destination_peer = add_trail->destination_peer;
5080 source_peer = add_trail->source_peer;
5081 trail_id = add_trail->trail_id;
5083 //FIXME: add a check that sender peer is not malicious. Make it a generic
5084 // function so that it can be used in all other functions where we need the
5085 // same functionality.
5087 /* I am not the destination of the trail. */
5088 if (0 != GNUNET_CRYPTO_cmp_peer_identity (&my_identity, &destination_peer))
5090 struct FriendInfo *target_friend;
5092 /* Get my location in the trail. */
5093 my_index = search_my_index (trail, trail_length);
5094 if (GNUNET_SYSERR == my_index)
5096 GNUNET_break_op (0);
5097 return GNUNET_SYSERR;
5101 next_hop = source_peer;
5103 next_hop = trail[trail_length - 1];
5105 /* Add in your routing table. */
5106 GNUNET_assert (GNUNET_OK == GDS_ROUTING_add (trail_id, next_hop, *peer));
5107 target_friend = GNUNET_CONTAINER_multipeermap_get (friend_peermap, &next_hop);
5108 GDS_NEIGHBOURS_send_add_trail (source_peer, destination_peer, trail_id,
5109 trail, trail_length, target_friend);
5113 /* I am the destination. Add an entry in routing table. */
5114 GNUNET_assert (GNUNET_OK == GDS_ROUTING_add (trail_id, *peer, my_identity));
5120 * Send trail teardown and free the finger trail in which the first
5121 * friend to reach to a finger is disconnected_friend
5122 * @param disconnected_friend PeerIdentity of friend which got disconnected
5123 * @param remove_finger Finger whose trail we need to check if it has
5124 * disconnected_friend as the first hop.
5125 * @return Total number of trails in which disconnected_friend was the first
5129 remove_matching_trails (const struct GNUNET_PeerIdentity *disconnected_friend,
5130 struct FingerInfo *remove_finger)
5132 unsigned int matching_trails_count;
5135 /* Number of trails with disconnected_friend as the first hop in the trail
5136 * to reach from me to remove_finger, NOT including endpoints. */
5137 matching_trails_count = 0;
5139 /* Iterate over all the trails of finger. */
5140 for (i = 0; i < remove_finger->trails_count; i++)
5142 struct Trail *trail;
5143 trail = &remove_finger->trail_list[i];
5145 if (GNUNET_NO == trail->is_present)
5148 /* First friend to reach to finger is disconnected_peer. */
5149 if (0 == GNUNET_CRYPTO_cmp_peer_identity (&trail->trail_head->peer,
5150 disconnected_friend))
5152 matching_trails_count++;
5153 send_trail_teardown (remove_finger, trail);
5154 if (trail->trail_length > 0)
5158 return matching_trails_count;
5163 * Iterate over finger_table entries.
5164 * 0. Ignore finger which is my_identity or if no valid entry present at
5165 * that finger index.
5166 * 1. If disconnected_friend is a finger, then free that entry. Don't send trail
5167 * teardown message, as there is no trail to reach to a finger which is a friend.
5168 * 2. Check if disconnected_friend is the first friend in the trail to reach to a finger.
5169 * 2.1 Send trail teardown message across all the trails in which disconnected
5170 * friend is the first friend in the trail. If disconnected_friend is the
5171 * first friend in all the trails to reach finger, then remove the finger.
5172 * @param disconnected_friend Peer identity of friend which got disconnected.
5175 remove_matching_fingers (const struct GNUNET_PeerIdentity *disconnected_friend)
5177 struct FingerInfo *remove_finger;
5178 int removed_trails_count;
5181 /* Iterate over finger table entries. */
5182 for (i = 0; i < MAX_FINGERS; i++)
5184 remove_finger = &finger_table[i];
5186 /* No finger stored at this trail index. */
5187 if (GNUNET_NO == remove_finger->is_present)
5190 /* I am my own finger, then ignore this finger. */
5191 if (0 == GNUNET_CRYPTO_cmp_peer_identity (&remove_finger->finger_identity,
5195 /* Is disconnected friend a finger? */
5196 if (0 == GNUNET_CRYPTO_cmp_peer_identity (disconnected_friend,
5197 &remove_finger->finger_identity))
5199 /* No trail to reach this finger as it is a friend, don't send
5200 * trail_teardown message. */
5201 remove_finger->is_present = GNUNET_NO;
5202 memset ((void *)&finger_table[i], 0, sizeof (finger_table[i]));
5206 /* Iterate over the list of trails to reach remove_finger. Check if
5207 * disconnected_friend is the first friend in any of the trail. */
5208 removed_trails_count = remove_matching_trails (disconnected_friend,
5211 /* All the finger trails had disconnected_friend as the first friend,
5212 * so free the finger. */
5213 if (removed_trails_count == remove_finger->trails_count)
5215 remove_finger->is_present = GNUNET_NO;
5216 memset ((void *)&finger_table[i], 0, sizeof (finger_table[i]));
5223 * Method called whenever a peer disconnects.
5225 * @param cls closure
5226 * @param peer peer identity this notification is about
5229 handle_core_disconnect (void *cls,
5230 const struct GNUNET_PeerIdentity *peer)
5232 struct FriendInfo *remove_friend;
5234 /* If disconnected to own identity, then return. */
5235 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
5238 GNUNET_assert (NULL != (remove_friend =
5239 GNUNET_CONTAINER_multipeermap_get (friend_peermap, peer)));
5241 /* Remove fingers with peer as first friend or if peer is a finger. */
5242 remove_matching_fingers (peer);
5244 /* Remove any trail from routing table of which peer is a part of. This function
5245 * internally sends a trail teardown message in the direction of which
5246 * disconnected peer is not part of. */
5247 GDS_ROUTING_remove_trail_by_peer (peer);
5249 /* Remove peer from friend_peermap. */
5250 GNUNET_assert (GNUNET_YES ==
5251 GNUNET_CONTAINER_multipeermap_remove (friend_peermap,
5255 if (0 != GNUNET_CONTAINER_multipeermap_size (friend_peermap))
5258 /* If there are no more friends in friend_peermap, then don't schedule
5259 * find_finger_trail_task. */
5260 if (GNUNET_SCHEDULER_NO_TASK != find_finger_trail_task)
5262 GNUNET_SCHEDULER_cancel (find_finger_trail_task);
5263 find_finger_trail_task = GNUNET_SCHEDULER_NO_TASK;
5272 * Method called whenever a peer connects.
5274 * @param cls closure
5275 * @param peer_identity peer identity this notification is about
5278 handle_core_connect (void *cls, const struct GNUNET_PeerIdentity *peer_identity)
5280 struct FriendInfo *friend;
5282 /* Check for connect to self message */
5283 if (0 == memcmp (&my_identity, peer_identity, sizeof (struct GNUNET_PeerIdentity)))
5286 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Connected to %s\n", GNUNET_i2s (peer_identity));
5288 /* If peer already exists in our friend_peermap, then exit. */
5289 if (GNUNET_YES == GNUNET_CONTAINER_multipeermap_contains (friend_peermap,
5296 GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# peers connected"), 1,
5299 friend = GNUNET_new (struct FriendInfo);
5300 friend->id = *peer_identity;
5302 GNUNET_assert (GNUNET_OK ==
5303 GNUNET_CONTAINER_multipeermap_put (friend_peermap,
5304 peer_identity, friend,
5305 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
5308 /* got a first connection, good time to start with FIND FINGER TRAIL requests...*/
5309 if (GNUNET_SCHEDULER_NO_TASK == find_finger_trail_task)
5310 find_finger_trail_task = GNUNET_SCHEDULER_add_now (&send_find_finger_trail_message, NULL);
5315 * To be called on core init/fail.
5317 * @param cls service closure
5318 * @param identity the public identity of this peer
5321 core_init (void *cls,
5322 const struct GNUNET_PeerIdentity *identity)
5324 my_identity = *identity;
5325 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
5326 "my_indentity = %s\n",GNUNET_i2s(&my_identity));
5328 FPRINTF (stderr,_("\nSUPU %s, %s, %d, my_identity = %s"),
5329 __FILE__, __func__,__LINE__, GNUNET_i2s (&my_identity));
5336 * Initialize finger table entries.
5339 finger_table_init ()
5344 /* FIXME: here we have set the whole entry of finger table to 0, so do we
5345 * need to initialize the trails to 0 */
5346 for(i = 0; i < MAX_FINGERS; i++)
5348 finger_table[i].is_present = GNUNET_NO;
5349 for (j = 0; j < MAXIMUM_TRAILS_PER_FINGER; j++)
5350 finger_table[i].trail_list[j].is_present = GNUNET_NO;
5351 memset ((void *)&finger_table[i], 0, sizeof (finger_table[i]));
5357 * Initialize neighbours subsystem.
5358 * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
5361 GDS_NEIGHBOURS_init (void)
5363 static struct GNUNET_CORE_MessageHandler core_handlers[] = {
5364 {&handle_dht_p2p_put, GNUNET_MESSAGE_TYPE_XDHT_P2P_PUT, 0},
5365 {&handle_dht_p2p_get, GNUNET_MESSAGE_TYPE_XDHT_P2P_GET, 0},
5366 {&handle_dht_p2p_get_result, GNUNET_MESSAGE_TYPE_XDHT_P2P_GET_RESULT, 0},
5367 {&handle_dht_p2p_trail_setup, GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_SETUP, 0},
5368 {&handle_dht_p2p_trail_setup_result, GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_SETUP_RESULT, 0},
5369 {&handle_dht_p2p_verify_successor, GNUNET_MESSAGE_TYPE_XDHT_P2P_VERIFY_SUCCESSOR, 0},
5370 {&handle_dht_p2p_verify_successor_result, GNUNET_MESSAGE_TYPE_XDHT_P2P_VERIFY_SUCCESSOR_RESULT, 0},
5371 {&handle_dht_p2p_notify_new_successor, GNUNET_MESSAGE_TYPE_XDHT_P2P_NOTIFY_NEW_SUCCESSOR, 0},
5372 {&handle_dht_p2p_trail_setup_rejection, GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_SETUP_REJECTION, 0},
5373 {&handle_dht_p2p_trail_compression, GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_COMPRESSION,
5374 sizeof (struct PeerTrailCompressionMessage)},
5375 {&handle_dht_p2p_trail_teardown, GNUNET_MESSAGE_TYPE_XDHT_P2P_TRAIL_TEARDOWN,
5376 sizeof (struct PeerTrailTearDownMessage)},
5377 {&handle_dht_p2p_add_trail, GNUNET_MESSAGE_TYPE_XDHT_P2P_ADD_TRAIL, 0},
5382 GNUNET_CORE_connect (GDS_cfg, NULL, &core_init, &handle_core_connect,
5383 &handle_core_disconnect, NULL, GNUNET_NO, NULL,
5384 GNUNET_NO, core_handlers);
5385 if (NULL == core_api)
5386 return GNUNET_SYSERR;
5388 friend_peermap = GNUNET_CONTAINER_multipeermap_create (256, GNUNET_NO);
5389 finger_table_init ();
5396 * Shutdown neighbours subsystem.
5399 GDS_NEIGHBOURS_done (void)
5401 if (NULL == core_api)
5404 GNUNET_CORE_disconnect (core_api);
5407 GNUNET_assert (0 == GNUNET_CONTAINER_multipeermap_size (friend_peermap));
5408 GNUNET_CONTAINER_multipeermap_destroy (friend_peermap);
5409 friend_peermap = NULL;
5411 if (GNUNET_SCHEDULER_NO_TASK != find_finger_trail_task)
5414 GNUNET_SCHEDULER_cancel (find_finger_trail_task);
5415 find_finger_trail_task = GNUNET_SCHEDULER_NO_TASK;
5423 * @return my identity
5425 struct GNUNET_PeerIdentity
5426 GDS_NEIGHBOURS_get_my_id (void)