2 This file is part of GNUnet.
3 (C) 2009, 2010 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
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12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
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17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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22 * @file dht/gnunet-service-dht.c
23 * @brief GNUnet DHT service
24 * @author Christian Grothoff
25 * @author Nathan Evans
29 #include "gnunet_block_lib.h"
30 #include "gnunet_client_lib.h"
31 #include "gnunet_getopt_lib.h"
32 #include "gnunet_os_lib.h"
33 #include "gnunet_protocols.h"
34 #include "gnunet_service_lib.h"
35 #include "gnunet_core_service.h"
36 #include "gnunet_signal_lib.h"
37 #include "gnunet_util_lib.h"
38 #include "gnunet_datacache_lib.h"
39 #include "gnunet_transport_service.h"
40 #include "gnunet_hello_lib.h"
41 #include "gnunet_dht_service.h"
42 #include "gnunet_statistics_service.h"
47 #define PRINT_TABLES GNUNET_NO
49 #define REAL_DISTANCE GNUNET_NO
51 #define EXTRA_CHECKS GNUNET_NO
54 * How many buckets will we allow total.
56 #define MAX_BUCKETS sizeof (GNUNET_HashCode) * 8
59 * Should the DHT issue FIND_PEER requests to get better routing tables?
61 #define DEFAULT_DO_FIND_PEER GNUNET_YES
64 * Defines whether find peer requests send their HELLO's outgoing,
65 * or expect replies to contain hellos.
67 #define FIND_PEER_WITH_HELLO GNUNET_YES
70 * What is the maximum number of peers in a given bucket.
72 #define DEFAULT_BUCKET_SIZE 4
74 #define DEFAULT_CORE_QUEUE_SIZE 32
77 * Minimum number of peers we need for "good" routing,
78 * any less than this and we will allow messages to
79 * travel much further through the network!
81 #define MINIMUM_PEER_THRESHOLD 20
83 #define DHT_MAX_RECENT 1000
85 #define FIND_PEER_CALC_INTERVAL GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 60)
88 * Default time to wait to send messages on behalf of other peers.
90 #define DHT_DEFAULT_P2P_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 10)
93 * Default importance for handling messages on behalf of other peers.
95 #define DHT_DEFAULT_P2P_IMPORTANCE 0
98 * How long to keep recent requests around by default.
100 #define DEFAULT_RECENT_REMOVAL GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 15)
103 * Default time to wait to send find peer messages sent by the dht service.
105 #define DHT_DEFAULT_FIND_PEER_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30)
108 * Default importance for find peer messages sent by the dht service.
110 #define DHT_DEFAULT_FIND_PEER_IMPORTANCE 8
113 * Default replication parameter for find peer messages sent by the dht service.
115 #define DHT_DEFAULT_FIND_PEER_REPLICATION 4
118 * Default options for find peer requests sent by the dht service.
120 #define DHT_DEFAULT_FIND_PEER_OPTIONS GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE
121 /*#define DHT_DEFAULT_FIND_PEER_OPTIONS GNUNET_DHT_RO_NONE*/
124 * How long at least to wait before sending another find peer request.
126 #define DHT_MINIMUM_FIND_PEER_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 2)
129 * How long at most to wait before sending another find peer request.
131 #define DHT_MAXIMUM_FIND_PEER_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 8)
134 * How often to update our preference levels for peers in our routing tables.
136 #define DHT_DEFAULT_PREFERENCE_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 2)
139 * How long at most on average will we allow a reply forward to take
140 * (before we quit sending out new requests)
142 #define MAX_REQUEST_TIME GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1)
145 * How many initial requests to send out (in true Kademlia fashion)
147 #define DEFAULT_KADEMLIA_REPLICATION 3
150 * Default frequency for sending malicious get messages
152 #define DEFAULT_MALICIOUS_GET_FREQUENCY 1000 /* Number of milliseconds */
155 * Default frequency for sending malicious put messages
157 #define DEFAULT_MALICIOUS_PUT_FREQUENCY 1000 /* Default is in milliseconds */
160 #define DHT_DEFAULT_PING_DELAY GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 1)
163 * Real maximum number of hops, at which point we refuse
164 * to forward the message.
166 #define DEFAULT_MAX_HOPS 10
169 * How many time differences between requesting a core send and
170 * the actual callback to remember.
172 #define MAX_REPLY_TIMES 8
174 enum ConvergenceOptions
177 * Use the linear method for convergence.
182 * Converge using a fast converging square
188 * Converge using a slower exponential
191 DHT_CONVERGE_EXPONENTIAL,
194 * Don't do any special convergence, allow
195 * the algorithm to hopefully route to closer
201 * Binary convergence, start routing to closest
202 * only after set number of hops.
208 * Linked list of messages to send to clients.
210 struct P2PPendingMessage
213 * Pointer to next item in the list
215 struct P2PPendingMessage *next;
218 * Pointer to previous item in the list
220 struct P2PPendingMessage *prev;
223 * Message importance level.
225 unsigned int importance;
228 * Time when this request was scheduled to be sent.
230 struct GNUNET_TIME_Absolute scheduled;
233 * How long to wait before sending message.
235 struct GNUNET_TIME_Relative timeout;
238 * Actual message to be sent; // avoid allocation
240 const struct GNUNET_MessageHeader *msg; // msg = (cast) &pm[1]; // memcpy (&pm[1], data, len);
245 * Per-peer information.
250 * Next peer entry (DLL)
252 struct PeerInfo *next;
255 * Prev peer entry (DLL)
257 struct PeerInfo *prev;
260 * Count of outstanding messages for peer.
262 unsigned int pending_count;
265 * Head of pending messages to be sent to this peer.
267 struct P2PPendingMessage *head;
270 * Tail of pending messages to be sent to this peer.
272 struct P2PPendingMessage *tail;
275 * Core handle for sending messages to this peer.
277 struct GNUNET_CORE_TransmitHandle *th;
280 * Task for scheduling message sends.
282 GNUNET_SCHEDULER_TaskIdentifier send_task;
285 * Task for scheduling preference updates
287 GNUNET_SCHEDULER_TaskIdentifier preference_task;
290 * Preference update context
292 struct GNUNET_CORE_InformationRequestContext *info_ctx;
295 * What is the identity of the peer?
297 struct GNUNET_PeerIdentity id;
301 * What is the average latency for replies received?
303 struct GNUNET_TIME_Relative latency;
306 * Transport level distance to peer.
308 unsigned int distance;
312 * Holds matching bits from peer to current target,
313 * used for distance comparisons between peers. May
314 * be considered a really bad idea.
315 * FIXME: remove this value (create struct which holds
316 * a single peerinfo and the matching bits, use
317 * that to pass to comparator)
319 unsigned int matching_bits;
322 * Task for scheduling periodic ping messages for this peer.
324 GNUNET_SCHEDULER_TaskIdentifier ping_task;
328 * Peers are grouped into buckets.
335 struct PeerInfo *head;
340 struct PeerInfo *tail;
343 * Number of peers in the bucket.
345 unsigned int peers_size;
349 * Linked list of messages to send to clients.
351 struct PendingMessage
354 * Pointer to next item in the list
356 struct PendingMessage *next;
359 * Pointer to previous item in the list
361 struct PendingMessage *prev;
364 * Actual message to be sent; // avoid allocation
366 const struct GNUNET_MessageHeader *msg; // msg = (cast) &pm[1]; // memcpy (&pm[1], data, len);
371 * Struct containing information about a client,
372 * handle to connect to it, and any pending messages
373 * that need to be sent to it.
378 * Linked list of active clients
380 struct ClientList *next;
383 * The handle to this client
385 struct GNUNET_SERVER_Client *client_handle;
388 * Handle to the current transmission request, NULL
391 struct GNUNET_CONNECTION_TransmitHandle *transmit_handle;
394 * Linked list of pending messages for this client
396 struct PendingMessage *pending_head;
399 * Tail of linked list of pending messages for this client
401 struct PendingMessage *pending_tail;
406 * Context containing information about a DHT message received.
408 struct DHT_MessageContext
411 * The client this request was received from.
412 * (NULL if received from another peer)
414 struct ClientList *client;
417 * The peer this request was received from.
418 * (NULL if received from local client)
420 const struct GNUNET_PeerIdentity *peer;
423 * Bloomfilter for this routing request.
425 struct GNUNET_CONTAINER_BloomFilter *bloom;
428 * extended query (see gnunet_block_lib.h).
433 * Bloomfilter to filter out duplicate replies.
435 struct GNUNET_CONTAINER_BloomFilter *reply_bf;
438 * The key this request was about
443 * How long should we wait to transmit this request?
445 struct GNUNET_TIME_Relative timeout;
448 * The unique identifier of this request
453 * Number of bytes in xquery.
458 * Mutator value for the reply_bf, see gnunet_block_lib.h
460 uint32_t reply_bf_mutator;
463 * Desired replication level
465 uint32_t replication;
468 * Network size estimate, either ours or the sum of
469 * those routed to thus far. =~ Log of number of peers
470 * chosen from for this request.
472 uint32_t network_size;
475 * Any message options for this request
477 uint32_t msg_options;
480 * How many hops has the message already traversed?
485 * How important is this message?
487 unsigned int importance;
490 * Should we (still) forward the request on to other peers?
495 * Did we forward this message? (may need to remember it!)
500 * Are we the closest known peer to this key (out of our neighbors?)
506 * Record used for remembering what peers are waiting for what
507 * responses (based on search key).
509 struct DHTRouteSource
514 struct DHTRouteSource *next;
519 struct DHTRouteSource *prev;
522 * Source of the request. Replies should be forwarded to
525 struct GNUNET_PeerIdentity source;
528 * If this was a local request, remember the client; otherwise NULL.
530 struct ClientList *client;
533 * Pointer to this nodes heap location (for removal)
535 struct GNUNET_CONTAINER_HeapNode *hnode;
538 * Back pointer to the record storing this information.
540 struct DHTQueryRecord *record;
543 * Task to remove this entry on timeout.
545 GNUNET_SCHEDULER_TaskIdentifier delete_task;
548 * Bloomfilter of peers we have already sent back as
549 * replies to the initial request. Allows us to not
550 * forward the same peer multiple times for a find peer
553 struct GNUNET_CONTAINER_BloomFilter *find_peers_responded;
558 * Entry in the DHT routing table.
560 struct DHTQueryRecord
563 * Head of DLL for result forwarding.
565 struct DHTRouteSource *head;
568 * Tail of DLL for result forwarding.
570 struct DHTRouteSource *tail;
573 * Key that the record concerns.
578 * GET message of this record (what we already forwarded?).
580 //DV_DHT_MESSAGE get; Try to get away with not saving this.
583 * Bloomfilter of the peers we've replied to so far
585 //struct GNUNET_BloomFilter *bloom_results; Don't think we need this, just remove from DLL on response.
590 * Context used to calculate the number of find peer messages
591 * per X time units since our last scheduled find peer message
592 * was sent. If we have seen too many messages, delay or don't
595 struct FindPeerMessageContext
599 struct GNUNET_TIME_Absolute start;
601 struct GNUNET_TIME_Absolute end;
605 * DHT Routing results structure
610 * Min heap for removal upon reaching limit
612 struct GNUNET_CONTAINER_Heap *minHeap;
615 * Hashmap for fast key based lookup
617 struct GNUNET_CONTAINER_MultiHashMap *hashmap;
622 * DHT structure for recent requests.
624 struct RecentRequests
627 * Min heap for removal upon reaching limit
629 struct GNUNET_CONTAINER_Heap *minHeap;
632 * Hashmap for key based lookup
634 struct GNUNET_CONTAINER_MultiHashMap *hashmap;
640 * Position of this node in the min heap.
642 struct GNUNET_CONTAINER_HeapNode *heap_node;
645 * Bloomfilter containing entries for peers
646 * we forwarded this request to.
648 struct GNUNET_CONTAINER_BloomFilter *bloom;
651 * Timestamp of this request, for ordering
654 struct GNUNET_TIME_Absolute timestamp;
657 * Key of this request.
662 * Unique identifier for this request.
667 * Task to remove this entry on timeout.
669 GNUNET_SCHEDULER_TaskIdentifier remove_task;
672 struct RepublishContext
687 * Which kind of convergence will we be using?
689 static enum ConvergenceOptions converge_option;
692 * Modifier for the convergence function
694 static float converge_modifier;
697 * Recent requests by hash/uid and by time inserted.
699 static struct RecentRequests recent;
702 * Context to use to calculate find peer rates.
704 static struct FindPeerMessageContext find_peer_context;
707 * Don't use our routing algorithm, always route
708 * to closest peer; initially send requests to 3
711 static unsigned int strict_kademlia;
714 * Routing option to end routing when closest peer found.
716 static unsigned int stop_on_closest;
719 * Routing option to end routing when data is found.
721 static unsigned int stop_on_found;
724 * Whether DHT needs to manage find peer requests, or
725 * an external force will do it on behalf of the DHT.
727 static unsigned int do_find_peer;
730 * Once we have stored an item in the DHT, refresh it
731 * according to our republish interval.
733 static unsigned int do_republish;
736 * Use the "real" distance metric when selecting the
737 * next routing hop. Can be less accurate.
739 static unsigned int use_real_distance;
742 * How many peers have we added since we sent out our last
745 static unsigned int newly_found_peers;
748 * Container of active queries we should remember
750 static struct DHTResults forward_list;
753 * Handle to the datacache service (for inserting/retrieving data)
755 static struct GNUNET_DATACACHE_Handle *datacache;
758 * Handle for the statistics service.
760 struct GNUNET_STATISTICS_Handle *stats;
764 * The configuration the DHT service is running with
766 static const struct GNUNET_CONFIGURATION_Handle *cfg;
769 * Handle to the core service
771 static struct GNUNET_CORE_Handle *coreAPI;
774 * Handle to the transport service, for getting our hello
776 static struct GNUNET_TRANSPORT_Handle *transport_handle;
779 * The identity of our peer.
781 static struct GNUNET_PeerIdentity my_identity;
784 * Short id of the peer, for printing
786 static char *my_short_id;
791 static struct GNUNET_MessageHeader *my_hello;
794 * Task to run when we shut down, cleaning up all our trash
796 static GNUNET_SCHEDULER_TaskIdentifier cleanup_task;
799 * The lowest currently used bucket.
801 static unsigned int lowest_bucket; /* Initially equal to MAX_BUCKETS - 1 */
804 * The maximum number of hops before we stop routing messages.
806 static unsigned long long max_hops;
809 * How often to republish content we have previously stored.
811 static struct GNUNET_TIME_Relative dht_republish_frequency;
814 * GNUNET_YES to stop at max_hops, GNUNET_NO to heuristically decide when to stop forwarding.
816 static int use_max_hops;
819 * The buckets (Kademlia routing table, complete with growth).
820 * Array of size MAX_BUCKET_SIZE.
822 static struct PeerBucket k_buckets[MAX_BUCKETS]; /* From 0 to MAX_BUCKETS - 1 */
825 * Hash map of all known peers, for easy removal from k_buckets on disconnect.
827 static struct GNUNET_CONTAINER_MultiHashMap *all_known_peers;
830 * Recently seen find peer requests.
832 static struct GNUNET_CONTAINER_MultiHashMap *recent_find_peer_requests;
835 * Maximum size for each bucket.
837 static unsigned int bucket_size = DEFAULT_BUCKET_SIZE; /* Initially equal to DEFAULT_BUCKET_SIZE */
840 * List of active clients.
842 static struct ClientList *client_list;
845 * Handle to the DHT logger.
847 static struct GNUNET_DHTLOG_Handle *dhtlog_handle;
850 * Whether or not to send routing debugging information
851 * to the dht logging server
853 static unsigned int debug_routes;
856 * Whether or not to send FULL route information to
859 static unsigned int debug_routes_extended;
862 * GNUNET_YES or GNUNET_NO, whether or not to act as
863 * a malicious node which drops all messages
865 static unsigned int malicious_dropper;
868 * GNUNET_YES or GNUNET_NO, whether or not to act as
869 * a malicious node which sends out lots of GETS
871 static unsigned int malicious_getter;
874 * GNUNET_YES or GNUNET_NO, whether or not to act as
875 * a malicious node which sends out lots of PUTS
877 static unsigned int malicious_putter;
880 * Frequency for malicious get requests.
882 static unsigned long long malicious_get_frequency;
885 * Frequency for malicious put requests.
887 static unsigned long long malicious_put_frequency;
890 * Kademlia replication
892 static unsigned long long kademlia_replication;
895 * Reply times for requests, if we are busy, don't send any
898 static struct GNUNET_TIME_Relative reply_times[MAX_REPLY_TIMES];
901 * Current counter for replies.
903 static unsigned int reply_counter;
906 * Our handle to the BLOCK library.
908 static struct GNUNET_BLOCK_Context *block_context;
912 * Forward declaration.
914 static size_t send_generic_reply (void *cls, size_t size, void *buf);
917 /** Declare here so retry_core_send is aware of it */
918 static size_t core_transmit_notify (void *cls, size_t size, void *buf);
921 * Convert unique ID to hash code.
923 * @param uid unique ID to convert
924 * @param hash set to uid (extended with zeros)
927 hash_from_uid (uint64_t uid, GNUNET_HashCode * hash)
929 memset (hash, 0, sizeof (GNUNET_HashCode));
930 *((uint64_t *) hash) = uid;
935 * Calculate the average send time between messages so that we can
936 * ignore certain requests if we get too busy.
938 * @return the average time between asking core to send a message
939 * and when the buffer for copying it is passed
941 static struct GNUNET_TIME_Relative
942 get_average_send_delay ()
945 unsigned int divisor;
946 struct GNUNET_TIME_Relative average_time;
947 average_time = GNUNET_TIME_relative_get_zero ();
949 for (i = 0; i < MAX_REPLY_TIMES; i++)
951 average_time = GNUNET_TIME_relative_add (average_time, reply_times[i]);
952 if (reply_times[i].abs_value == (uint64_t) 0)
962 average_time = GNUNET_TIME_relative_divide (average_time, divisor);
964 "Avg send delay: %u sends is %llu\n",
965 divisor, (unsigned long long) average_time.abs_value);
971 * Given the largest send delay, artificially decrease it
972 * so the next time around we may have a chance at sending
976 decrease_max_send_delay (struct GNUNET_TIME_Relative max_time)
979 for (i = 0; i < MAX_REPLY_TIMES; i++)
981 if (reply_times[i].rel_value == max_time.rel_value)
983 reply_times[i].rel_value = reply_times[i].rel_value / 2;
990 * Find the maximum send time of the recently sent values.
992 * @return the average time between asking core to send a message
993 * and when the buffer for copying it is passed
995 static struct GNUNET_TIME_Relative
996 get_max_send_delay ()
999 struct GNUNET_TIME_Relative max_time;
1000 max_time = GNUNET_TIME_relative_get_zero ();
1002 for (i = 0; i < MAX_REPLY_TIMES; i++)
1004 if (reply_times[i].rel_value > max_time.rel_value)
1005 max_time.rel_value = reply_times[i].rel_value;
1008 if (max_time.rel_value > MAX_REQUEST_TIME.rel_value)
1009 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Max send delay was %llu\n",
1010 (unsigned long long) max_time.rel_value);
1015 increment_stats (const char *value)
1019 GNUNET_STATISTICS_update (stats, value, 1, GNUNET_NO);
1024 * Try to send another message from our core send list
1027 try_core_send (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1029 struct PeerInfo *peer = cls;
1030 struct P2PPendingMessage *pending;
1033 peer->send_task = GNUNET_SCHEDULER_NO_TASK;
1035 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
1038 if (peer->th != NULL)
1039 return; /* Message send already in progress */
1041 pending = peer->head;
1042 if (pending != NULL)
1044 ssize = ntohs (pending->msg->size);
1046 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1047 "`%s:%s': Calling notify_transmit_ready with size %d for peer %s\n",
1048 my_short_id, "DHT", ssize, GNUNET_i2s (&peer->id));
1050 pending->scheduled = GNUNET_TIME_absolute_get ();
1052 if (reply_counter >= MAX_REPLY_TIMES)
1055 GNUNET_CORE_notify_transmit_ready (coreAPI, pending->importance,
1056 pending->timeout, &peer->id, ssize,
1057 &core_transmit_notify, peer);
1058 if (peer->th == NULL)
1059 increment_stats ("# notify transmit ready failed");
1064 * Function called to send a request out to another peer.
1065 * Called both for locally initiated requests and those
1066 * received from other peers.
1068 * @param msg the encapsulated message
1069 * @param peer the peer to forward the message to
1070 * @param msg_ctx the context of the message (hop count, bloom, etc.)
1073 forward_result_message (const struct GNUNET_MessageHeader *msg,
1074 struct PeerInfo *peer,
1075 struct DHT_MessageContext *msg_ctx)
1077 struct GNUNET_DHT_P2PRouteResultMessage *result_message;
1078 struct P2PPendingMessage *pending;
1082 increment_stats (STAT_RESULT_FORWARDS);
1084 sizeof (struct GNUNET_DHT_P2PRouteResultMessage) + ntohs (msg->size);
1085 GNUNET_assert (msize <= GNUNET_SERVER_MAX_MESSAGE_SIZE);
1086 psize = sizeof (struct P2PPendingMessage) + msize;
1087 pending = GNUNET_malloc (psize);
1088 pending->msg = (struct GNUNET_MessageHeader *) &pending[1];
1089 pending->importance = DHT_SEND_PRIORITY;
1090 pending->timeout = GNUNET_TIME_relative_get_forever ();
1091 result_message = (struct GNUNET_DHT_P2PRouteResultMessage *) pending->msg;
1092 result_message->header.size = htons (msize);
1093 result_message->header.type =
1094 htons (GNUNET_MESSAGE_TYPE_DHT_P2P_ROUTE_RESULT);
1095 result_message->put_path_length = htons (0); /* FIXME: implement */
1096 result_message->get_path_length = htons (0); /* FIXME: implement */
1097 result_message->options = htonl (msg_ctx->msg_options);
1098 result_message->hop_count = htonl (msg_ctx->hop_count + 1);
1099 GNUNET_assert (GNUNET_OK ==
1100 GNUNET_CONTAINER_bloomfilter_get_raw_data (msg_ctx->bloom,
1104 result_message->unique_id = GNUNET_htonll (msg_ctx->unique_id);
1105 memcpy (&result_message->key, &msg_ctx->key, sizeof (GNUNET_HashCode));
1106 memcpy (&result_message[1], msg, ntohs (msg->size));
1108 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1109 "%s:%s Adding pending message size %d for peer %s\n",
1110 my_short_id, "DHT", msize, GNUNET_i2s (&peer->id));
1112 peer->pending_count++;
1113 increment_stats ("# pending messages scheduled");
1114 GNUNET_CONTAINER_DLL_insert_after (peer->head, peer->tail, peer->tail,
1116 if (peer->send_task == GNUNET_SCHEDULER_NO_TASK)
1117 peer->send_task = GNUNET_SCHEDULER_add_now (&try_core_send, peer);
1122 * Called when core is ready to send a message we asked for
1123 * out to the destination.
1125 * @param cls closure (NULL)
1126 * @param size number of bytes available in buf
1127 * @param buf where the callee should write the message
1128 * @return number of bytes written to buf
1131 core_transmit_notify (void *cls, size_t size, void *buf)
1133 struct PeerInfo *peer = cls;
1135 struct P2PPendingMessage *pending;
1142 /* client disconnected */
1144 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': buffer was NULL\n",
1145 my_short_id, "DHT");
1150 if (peer->head == NULL)
1154 pending = peer->head;
1156 reply_times[reply_counter] =
1157 GNUNET_TIME_absolute_get_difference (pending->scheduled,
1158 GNUNET_TIME_absolute_get ());
1159 msize = ntohs (pending->msg->size);
1163 memcpy (cbuf, pending->msg, msize);
1164 peer->pending_count--;
1165 increment_stats ("# pending messages sent");
1166 GNUNET_assert (peer->pending_count >= 0);
1167 GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, pending);
1168 GNUNET_free (pending);
1171 while (NULL != pending &&
1172 (size - off >= (msize = ntohs (pending->msg->size))))
1174 memcpy (&cbuf[off], pending->msg, msize);
1176 peer->pending_count--;
1177 increment_stats ("# pending messages sent");
1178 GNUNET_assert (peer->pending_count >= 0);
1179 GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, pending);
1180 GNUNET_free (pending);
1181 pending = peer->head;
1184 if ((peer->head != NULL) && (peer->send_task == GNUNET_SCHEDULER_NO_TASK))
1185 peer->send_task = GNUNET_SCHEDULER_add_now (&try_core_send, peer);
1192 * Compute the distance between have and target as a 32-bit value.
1193 * Differences in the lower bits must count stronger than differences
1194 * in the higher bits.
1196 * @return 0 if have==target, otherwise a number
1197 * that is larger as the distance between
1198 * the two hash codes increases
1201 distance (const GNUNET_HashCode * target, const GNUNET_HashCode * have)
1203 unsigned int bucket;
1208 /* We have to represent the distance between two 2^9 (=512)-bit
1209 numbers as a 2^5 (=32)-bit number with "0" being used for the
1210 two numbers being identical; furthermore, we need to
1211 guarantee that a difference in the number of matching
1212 bits is always represented in the result.
1214 We use 2^32/2^9 numerical values to distinguish between
1215 hash codes that have the same LSB bit distance and
1216 use the highest 2^9 bits of the result to signify the
1217 number of (mis)matching LSB bits; if we have 0 matching
1218 and hence 512 mismatching LSB bits we return -1 (since
1219 512 itself cannot be represented with 9 bits) */
1221 /* first, calculate the most significant 9 bits of our
1222 result, aka the number of LSBs */
1223 bucket = GNUNET_CRYPTO_hash_matching_bits (target, have);
1224 /* bucket is now a value between 0 and 512 */
1226 return 0; /* perfect match */
1228 return (unsigned int) -1; /* LSB differs; use max (if we did the bit-shifting
1229 below, we'd end up with max+1 (overflow)) */
1231 /* calculate the most significant bits of the final result */
1232 msb = (512 - bucket) << (32 - 9);
1233 /* calculate the 32-9 least significant bits of the final result by
1234 looking at the differences in the 32-9 bits following the
1235 mismatching bit at 'bucket' */
1237 for (i = bucket + 1;
1238 (i < sizeof (GNUNET_HashCode) * 8) && (i < bucket + 1 + 32 - 9); i++)
1240 if (GNUNET_CRYPTO_hash_get_bit (target, i) !=
1241 GNUNET_CRYPTO_hash_get_bit (have, i))
1242 lsb |= (1 << (bucket + 32 - 9 - i)); /* first bit set will be 10,
1243 last bit set will be 31 -- if
1244 i does not reach 512 first... */
1250 * Return a number that is larger the closer the
1251 * "have" GNUNET_hash code is to the "target".
1253 * @return inverse distance metric, non-zero.
1254 * Must fudge the value if NO bits match.
1257 inverse_distance (const GNUNET_HashCode * target,
1258 const GNUNET_HashCode * have)
1260 if (GNUNET_CRYPTO_hash_matching_bits (target, have) == 0)
1261 return 1; /* Never return 0! */
1262 return ((unsigned int) -1) - distance (target, have);
1266 * Find the optimal bucket for this key, regardless
1267 * of the current number of buckets in use.
1269 * @param hc the hashcode to compare our identity to
1271 * @return the proper bucket index, or GNUNET_SYSERR
1272 * on error (same hashcode)
1275 find_bucket (const GNUNET_HashCode * hc)
1279 bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, hc);
1280 if (bits == MAX_BUCKETS)
1281 return GNUNET_SYSERR;
1282 return MAX_BUCKETS - bits - 1;
1286 * Find which k-bucket this peer should go into,
1287 * taking into account the size of the k-bucket
1288 * array. This means that if more bits match than
1289 * there are currently buckets, lowest_bucket will
1292 * @param hc GNUNET_HashCode we are finding the bucket for.
1294 * @return the proper bucket index for this key,
1295 * or GNUNET_SYSERR on error (same hashcode)
1298 find_current_bucket (const GNUNET_HashCode * hc)
1301 actual_bucket = find_bucket (hc);
1303 if (actual_bucket == GNUNET_SYSERR) /* hc and our peer identity match! */
1304 return lowest_bucket;
1305 else if (actual_bucket < lowest_bucket) /* actual_bucket not yet used */
1306 return lowest_bucket;
1308 return actual_bucket;
1313 * Find a routing table entry from a peer identity
1315 * @param peer the peer to look up
1317 * @return the bucket number holding the peer, GNUNET_SYSERR if not found
1320 find_bucket_by_peer (const struct PeerInfo *peer)
1323 struct PeerInfo *pos;
1325 for (bucket = lowest_bucket; bucket < MAX_BUCKETS - 1; bucket++)
1327 pos = k_buckets[bucket].head;
1336 return GNUNET_SYSERR; /* No such peer. */
1342 * Print the complete routing table for this peer.
1345 print_routing_table ()
1348 struct PeerInfo *pos;
1349 char char_buf[30000];
1351 memset (char_buf, 0, sizeof (char_buf));
1354 sprintf (&char_buf[char_pos], "Printing routing table for peer %s\n",
1356 //fprintf(stderr, "Printing routing table for peer %s\n", my_short_id);
1357 for (bucket = lowest_bucket; bucket < MAX_BUCKETS; bucket++)
1359 pos = k_buckets[bucket].head;
1360 char_pos += sprintf (&char_buf[char_pos], "Bucket %d:\n", bucket);
1361 //fprintf(stderr, "Bucket %d:\n", bucket);
1364 //fprintf(stderr, "\tPeer %s, best bucket %d, %d bits match\n", GNUNET_i2s(&pos->id), find_bucket(&pos->id.hashPubKey), GNUNET_CRYPTO_hash_matching_bits(&pos->id.hashPubKey, &my_identity.hashPubKey));
1366 sprintf (&char_buf[char_pos],
1367 "\tPeer %s, best bucket %d, %d bits match\n",
1368 GNUNET_i2s (&pos->id), find_bucket (&pos->id.hashPubKey),
1369 GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey,
1375 fprintf (stderr, "%s", char_buf);
1381 * Find a routing table entry from a peer identity
1383 * @param peer the peer identity to look up
1385 * @return the routing table entry, or NULL if not found
1387 static struct PeerInfo *
1388 find_peer_by_id (const struct GNUNET_PeerIdentity *peer)
1391 struct PeerInfo *pos;
1392 bucket = find_current_bucket (&peer->hashPubKey);
1394 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
1397 pos = k_buckets[bucket].head;
1400 if (0 == memcmp (&pos->id, peer, sizeof (struct GNUNET_PeerIdentity)))
1404 return NULL; /* No such peer. */
1407 /* Forward declaration */
1409 update_core_preference (void *cls,
1410 const struct GNUNET_SCHEDULER_TaskContext *tc);
1412 * Function called with statistics about the given peer.
1414 * @param cls closure
1415 * @param peer identifies the peer
1416 * @param bpm_out set to the current bandwidth limit (sending) for this peer
1417 * @param amount set to the amount that was actually reserved or unreserved;
1418 * either the full requested amount or zero (no partial reservations)
1419 * @param preference current traffic preference for the given peer
1422 update_core_preference_finish (void *cls,
1423 const struct GNUNET_PeerIdentity *peer,
1424 struct GNUNET_BANDWIDTH_Value32NBO bpm_out,
1425 int amount, uint64_t preference)
1427 struct PeerInfo *peer_info = cls;
1428 peer_info->info_ctx = NULL;
1429 GNUNET_SCHEDULER_add_delayed (DHT_DEFAULT_PREFERENCE_INTERVAL,
1430 &update_core_preference, peer_info);
1434 update_core_preference (void *cls,
1435 const struct GNUNET_SCHEDULER_TaskContext *tc)
1437 struct PeerInfo *peer = cls;
1438 uint64_t preference;
1439 unsigned int matching;
1440 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
1445 GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey,
1446 &peer->id.hashPubKey);
1449 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1450 "Peer identifier matches by %u bits, only shifting as much as we can!\n",
1454 preference = 1LL << matching;
1455 peer->info_ctx = GNUNET_CORE_peer_change_preference (coreAPI,
1457 GNUNET_TIME_relative_get_forever
1459 GNUNET_BANDWIDTH_value_init
1462 &update_core_preference_finish,
1467 * Really add a peer to a bucket (only do assertions
1470 * @param peer GNUNET_PeerIdentity of the peer to add
1471 * @param bucket the already figured out bucket to add
1473 * @param atsi performance information
1475 * @return the newly added PeerInfo
1477 static struct PeerInfo *
1478 add_peer (const struct GNUNET_PeerIdentity *peer,
1479 unsigned int bucket,
1480 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
1482 struct PeerInfo *new_peer;
1483 GNUNET_assert (bucket < MAX_BUCKETS);
1484 GNUNET_assert (peer != NULL);
1485 new_peer = GNUNET_malloc (sizeof (struct PeerInfo));
1487 new_peer->latency = latency;
1488 new_peer->distance = distance;
1491 memcpy (&new_peer->id, peer, sizeof (struct GNUNET_PeerIdentity));
1493 GNUNET_CONTAINER_DLL_insert_after (k_buckets[bucket].head,
1494 k_buckets[bucket].tail,
1495 k_buckets[bucket].tail, new_peer);
1496 k_buckets[bucket].peers_size++;
1498 if ((GNUNET_CRYPTO_hash_matching_bits
1499 (&my_identity.hashPubKey, &peer->hashPubKey) > 0)
1500 && (k_buckets[bucket].peers_size <= bucket_size))
1502 #if DO_UPDATE_PREFERENCE
1503 new_peer->preference_task =
1504 GNUNET_SCHEDULER_add_now (&update_core_preference, new_peer);
1512 * Given a peer and its corresponding bucket,
1513 * remove it from that bucket. Does not free
1514 * the PeerInfo struct, nor cancel messages
1515 * or free messages waiting to be sent to this
1518 * @param peer the peer to remove
1519 * @param bucket the bucket the peer belongs to
1522 remove_peer (struct PeerInfo *peer, unsigned int bucket)
1524 GNUNET_assert (k_buckets[bucket].peers_size > 0);
1525 GNUNET_CONTAINER_DLL_remove (k_buckets[bucket].head,
1526 k_buckets[bucket].tail, peer);
1527 k_buckets[bucket].peers_size--;
1529 if ((bucket == lowest_bucket) && (k_buckets[lowest_bucket].peers_size == 0)
1530 && (lowest_bucket < MAX_BUCKETS - 1))
1536 * Removes peer from a bucket, then frees associated
1537 * resources and frees peer.
1539 * @param peer peer to be removed and freed
1540 * @param bucket which bucket this peer belongs to
1543 delete_peer (struct PeerInfo *peer, unsigned int bucket)
1545 struct P2PPendingMessage *pos;
1546 struct P2PPendingMessage *next;
1548 struct PeerInfo *peer_pos;
1550 peer_pos = k_buckets[bucket].head;
1551 while ((peer_pos != NULL) && (peer_pos != peer))
1552 peer_pos = peer_pos->next;
1553 if (peer_pos == NULL)
1555 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1556 "%s:%s: Expected peer `%s' in bucket %d\n", my_short_id,
1557 "DHT", GNUNET_i2s (&peer->id), bucket);
1558 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1559 "%s:%s: Lowest bucket: %d, find_current_bucket: %d, peer resides in bucket: %d\n",
1560 my_short_id, "DHT", lowest_bucket,
1561 find_current_bucket (&peer->id.hashPubKey),
1562 find_bucket_by_peer (peer));
1564 GNUNET_assert (peer_pos != NULL);
1566 remove_peer (peer, bucket); /* First remove the peer from its bucket */
1568 if (peer->send_task != GNUNET_SCHEDULER_NO_TASK)
1569 GNUNET_SCHEDULER_cancel (peer->send_task);
1570 if ((peer->th != NULL) && (coreAPI != NULL))
1571 GNUNET_CORE_notify_transmit_ready_cancel (peer->th);
1574 while (pos != NULL) /* Remove any pending messages for this peer */
1577 ("# dht pending messages discarded (due to disconnect/shutdown)");
1583 GNUNET_assert (GNUNET_CONTAINER_multihashmap_contains
1584 (all_known_peers, &peer->id.hashPubKey));
1585 GNUNET_assert (GNUNET_YES ==
1586 GNUNET_CONTAINER_multihashmap_remove (all_known_peers,
1587 &peer->id.hashPubKey,
1594 * Iterator over hash map entries.
1596 * @param cls closure
1597 * @param key current key code
1598 * @param value PeerInfo of the peer to move to new lowest bucket
1599 * @return GNUNET_YES if we should continue to
1604 move_lowest_bucket (void *cls, const GNUNET_HashCode * key, void *value)
1606 struct PeerInfo *peer = value;
1609 GNUNET_assert (lowest_bucket > 0);
1610 new_bucket = lowest_bucket - 1;
1611 remove_peer (peer, lowest_bucket);
1612 GNUNET_CONTAINER_DLL_insert_after (k_buckets[new_bucket].head,
1613 k_buckets[new_bucket].tail,
1614 k_buckets[new_bucket].tail, peer);
1615 k_buckets[new_bucket].peers_size++;
1621 * The current lowest bucket is full, so change the lowest
1622 * bucket to the next lower down, and move any appropriate
1623 * entries in the current lowest bucket to the new bucket.
1626 enable_next_bucket ()
1628 struct GNUNET_CONTAINER_MultiHashMap *to_remove;
1629 struct PeerInfo *pos;
1630 GNUNET_assert (lowest_bucket > 0);
1631 to_remove = GNUNET_CONTAINER_multihashmap_create (bucket_size);
1632 pos = k_buckets[lowest_bucket].head;
1635 fprintf (stderr, "Printing RT before new bucket\n");
1636 print_routing_table ();
1638 /* Populate the array of peers which should be in the next lowest bucket */
1641 if (find_bucket (&pos->id.hashPubKey) < lowest_bucket)
1642 GNUNET_CONTAINER_multihashmap_put (to_remove, &pos->id.hashPubKey,
1644 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
1648 /* Remove peers from lowest bucket, insert into next lowest bucket */
1649 GNUNET_CONTAINER_multihashmap_iterate (to_remove, &move_lowest_bucket,
1651 GNUNET_CONTAINER_multihashmap_destroy (to_remove);
1652 lowest_bucket = lowest_bucket - 1;
1654 fprintf (stderr, "Printing RT after new bucket\n");
1655 print_routing_table ();
1660 * Find the closest peer in our routing table to the
1663 * @return The closest peer in our routing table to the
1664 * key, or NULL on error.
1666 static struct PeerInfo *
1667 find_closest_peer (const GNUNET_HashCode * hc)
1669 struct PeerInfo *pos;
1670 struct PeerInfo *current_closest;
1671 unsigned int lowest_distance;
1672 unsigned int temp_distance;
1676 lowest_distance = -1;
1678 if (k_buckets[lowest_bucket].peers_size == 0)
1681 current_closest = NULL;
1682 for (bucket = lowest_bucket; bucket < MAX_BUCKETS; bucket++)
1684 pos = k_buckets[bucket].head;
1686 while ((pos != NULL) && (count < bucket_size))
1688 temp_distance = distance (&pos->id.hashPubKey, hc);
1689 if (temp_distance <= lowest_distance)
1691 lowest_distance = temp_distance;
1692 current_closest = pos;
1698 GNUNET_assert (current_closest != NULL);
1699 return current_closest;
1704 * Function called to send a request out to another peer.
1705 * Called both for locally initiated requests and those
1706 * received from other peers.
1708 * @param msg the encapsulated message
1709 * @param peer the peer to forward the message to
1710 * @param msg_ctx the context of the message (hop count, bloom, etc.)
1713 forward_message (const struct GNUNET_MessageHeader *msg,
1714 struct PeerInfo *peer, struct DHT_MessageContext *msg_ctx)
1716 struct GNUNET_DHT_P2PRouteMessage *route_message;
1717 struct P2PPendingMessage *pending;
1721 increment_stats (STAT_ROUTE_FORWARDS);
1722 GNUNET_assert (peer != NULL);
1723 if ((msg_ctx->closest != GNUNET_YES)
1724 && (peer == find_closest_peer (&msg_ctx->key)))
1725 increment_stats (STAT_ROUTE_FORWARDS_CLOSEST);
1727 msize = sizeof (struct GNUNET_DHT_P2PRouteMessage) + ntohs (msg->size);
1728 GNUNET_assert (msize <= GNUNET_SERVER_MAX_MESSAGE_SIZE);
1729 psize = sizeof (struct P2PPendingMessage) + msize;
1730 pending = GNUNET_malloc (psize);
1731 pending->msg = (struct GNUNET_MessageHeader *) &pending[1];
1732 pending->importance = msg_ctx->importance;
1733 pending->timeout = msg_ctx->timeout;
1734 route_message = (struct GNUNET_DHT_P2PRouteMessage *) pending->msg;
1735 route_message->header.size = htons (msize);
1736 route_message->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_ROUTE);
1737 route_message->options = htonl (msg_ctx->msg_options);
1738 route_message->hop_count = htonl (msg_ctx->hop_count + 1);
1739 route_message->network_size = htonl (msg_ctx->network_size);
1740 route_message->desired_replication_level = htonl (msg_ctx->replication);
1741 route_message->unique_id = GNUNET_htonll (msg_ctx->unique_id);
1742 if (msg_ctx->bloom != NULL)
1743 GNUNET_assert (GNUNET_OK ==
1744 GNUNET_CONTAINER_bloomfilter_get_raw_data (msg_ctx->bloom,
1748 memcpy (&route_message->key, &msg_ctx->key, sizeof (GNUNET_HashCode));
1749 memcpy (&route_message[1], msg, ntohs (msg->size));
1751 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1752 "%s:%s Adding pending message size %d for peer %s\n",
1753 my_short_id, "DHT", msize, GNUNET_i2s (&peer->id));
1755 peer->pending_count++;
1756 increment_stats ("# pending messages scheduled");
1757 GNUNET_CONTAINER_DLL_insert_after (peer->head, peer->tail, peer->tail,
1759 if (peer->send_task == GNUNET_SCHEDULER_NO_TASK)
1760 peer->send_task = GNUNET_SCHEDULER_add_now (&try_core_send, peer);
1765 * Task used to send ping messages to peers so that
1766 * they don't get disconnected.
1768 * @param cls the peer to send a ping message to
1769 * @param tc context, reason, etc.
1772 periodic_ping_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1774 struct PeerInfo *peer = cls;
1775 struct GNUNET_MessageHeader ping_message;
1776 struct DHT_MessageContext msg_ctx;
1778 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
1781 ping_message.size = htons (sizeof (struct GNUNET_MessageHeader));
1782 ping_message.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_PING);
1784 memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext));
1786 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1787 "%s:%s Sending periodic ping to %s\n", my_short_id, "DHT",
1788 GNUNET_i2s (&peer->id));
1790 forward_message (&ping_message, peer, &msg_ctx);
1792 GNUNET_SCHEDULER_add_delayed (DHT_DEFAULT_PING_DELAY, &periodic_ping_task,
1797 * Schedule PING messages for the top X peers in each
1798 * bucket of the routing table (so core won't disconnect them!)
1801 schedule_ping_messages ()
1803 unsigned int bucket;
1805 struct PeerInfo *pos;
1806 for (bucket = lowest_bucket; bucket < MAX_BUCKETS; bucket++)
1808 pos = k_buckets[bucket].head;
1812 if ((count < bucket_size)
1813 && (pos->ping_task == GNUNET_SCHEDULER_NO_TASK))
1814 GNUNET_SCHEDULER_add_now (&periodic_ping_task, pos);
1815 else if ((count >= bucket_size)
1816 && (pos->ping_task != GNUNET_SCHEDULER_NO_TASK))
1818 GNUNET_SCHEDULER_cancel (pos->ping_task);
1819 pos->ping_task = GNUNET_SCHEDULER_NO_TASK;
1829 * Attempt to add a peer to our k-buckets.
1831 * @param peer the peer identity of the peer being added
1832 * @param bucket the bucket that we want this peer to go in
1833 * @param latency transport latency of this peer
1834 * @param distance transport distance to this peer
1836 * @return NULL if the peer was not added,
1837 * pointer to PeerInfo for new peer otherwise
1839 static struct PeerInfo *
1840 try_add_peer (const struct GNUNET_PeerIdentity *peer,
1841 unsigned int bucket,
1842 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
1845 struct PeerInfo *new_peer;
1847 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
1850 peer_bucket = find_current_bucket (&peer->hashPubKey);
1852 GNUNET_assert (peer_bucket >= lowest_bucket);
1853 new_peer = add_peer (peer, peer_bucket, atsi);
1855 if ((k_buckets[lowest_bucket].peers_size) >= bucket_size)
1856 enable_next_bucket ();
1858 schedule_ping_messages ();
1865 * Task run to check for messages that need to be sent to a client.
1867 * @param client a ClientList, containing the client and any messages to be sent to it
1870 process_pending_messages (struct ClientList *client)
1872 if (client->pending_head == NULL)
1874 if (client->transmit_handle != NULL)
1877 client->transmit_handle =
1878 GNUNET_SERVER_notify_transmit_ready (client->client_handle,
1879 ntohs (client->pending_head->
1881 GNUNET_TIME_UNIT_FOREVER_REL,
1882 &send_generic_reply, client);
1886 * Callback called as a result of issuing a GNUNET_SERVER_notify_transmit_ready
1887 * request. A ClientList is passed as closure, take the head of the list
1888 * and copy it into buf, which has the result of sending the message to the
1891 * @param cls closure to this call
1892 * @param size maximum number of bytes available to send
1893 * @param buf where to copy the actual message to
1895 * @return the number of bytes actually copied, 0 indicates failure
1898 send_generic_reply (void *cls, size_t size, void *buf)
1900 struct ClientList *client = cls;
1902 struct PendingMessage *reply;
1906 client->transmit_handle = NULL;
1909 /* client disconnected */
1913 while ((NULL != (reply = client->pending_head)) &&
1914 (size >= off + (msize = ntohs (reply->msg->size))))
1916 GNUNET_CONTAINER_DLL_remove (client->pending_head,
1917 client->pending_tail, reply);
1918 memcpy (&cbuf[off], reply->msg, msize);
1919 GNUNET_free (reply);
1922 process_pending_messages (client);
1924 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1925 "Transmitted %u bytes of replies to client\n",
1926 (unsigned int) off);
1933 * Add a PendingMessage to the clients list of messages to be sent
1935 * @param client the active client to send the message to
1936 * @param pending_message the actual message to send
1939 add_pending_message (struct ClientList *client,
1940 struct PendingMessage *pending_message)
1942 GNUNET_CONTAINER_DLL_insert_after (client->pending_head,
1943 client->pending_tail,
1944 client->pending_tail, pending_message);
1945 process_pending_messages (client);
1950 * Called when a reply needs to be sent to a client, as
1951 * a result it found to a GET or FIND PEER request.
1953 * @param client the client to send the reply to
1954 * @param message the encapsulated message to send
1955 * @param uid the unique identifier of this request
1958 send_reply_to_client (struct ClientList *client,
1959 const struct GNUNET_MessageHeader *message,
1960 unsigned long long uid, const GNUNET_HashCode * key)
1962 struct GNUNET_DHT_RouteResultMessage *reply;
1963 struct PendingMessage *pending_message;
1967 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1968 "`%s:%s': Sending reply to client.\n", my_short_id, "DHT");
1970 msize = ntohs (message->size);
1971 tsize = sizeof (struct GNUNET_DHT_RouteResultMessage) + msize;
1972 if (tsize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1974 GNUNET_break_op (0);
1977 pending_message = GNUNET_malloc (sizeof (struct PendingMessage) + tsize);
1978 pending_message->msg = (struct GNUNET_MessageHeader *) &pending_message[1];
1979 reply = (struct GNUNET_DHT_RouteResultMessage *) &pending_message[1];
1980 reply->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_LOCAL_ROUTE_RESULT);
1981 reply->header.size = htons (tsize);
1982 reply->put_path_length = htons (0); /* FIXME: implement */
1983 reply->get_path_length = htons (0); /* FIXME: implement */
1984 reply->unique_id = GNUNET_htonll (uid);
1986 memcpy (&reply[1], message, msize);
1987 add_pending_message (client, pending_message);
1991 * Consider whether or not we would like to have this peer added to
1992 * our routing table. Check whether bucket for this peer is full,
1993 * if so return negative; if not return positive. Since peers are
1994 * only added on CORE level connect, this doesn't actually add the
1995 * peer to the routing table.
1997 * @param peer the peer we are considering adding
1999 * @return GNUNET_YES if we want this peer, GNUNET_NO if not (bucket
2003 consider_peer (struct GNUNET_PeerIdentity *peer)
2008 GNUNET_CONTAINER_multihashmap_contains (all_known_peers,
2011 memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity))))
2012 return GNUNET_NO; /* We already know this peer (are connected even!) */
2013 bucket = find_current_bucket (&peer->hashPubKey);
2015 if ((k_buckets[bucket].peers_size < bucket_size)
2016 || ((bucket == lowest_bucket) && (lowest_bucket > 0)))
2024 * Task used to remove forwarding entries, either
2025 * after timeout, when full, or on shutdown.
2027 * @param cls the entry to remove
2028 * @param tc context, reason, etc.
2031 remove_forward_entry (void *cls,
2032 const struct GNUNET_SCHEDULER_TaskContext *tc)
2034 struct DHTRouteSource *source_info = cls;
2035 struct DHTQueryRecord *record;
2037 GNUNET_CONTAINER_heap_remove_node (forward_list.minHeap,
2038 source_info->hnode);
2039 record = source_info->record;
2040 GNUNET_CONTAINER_DLL_remove (record->head, record->tail, source_info);
2042 if (record->head == NULL) /* No more entries in DLL */
2044 GNUNET_assert (GNUNET_YES ==
2045 GNUNET_CONTAINER_multihashmap_remove
2046 (forward_list.hashmap, &record->key, record));
2047 GNUNET_free (record);
2049 if (source_info->find_peers_responded != NULL)
2050 GNUNET_CONTAINER_bloomfilter_free (source_info->find_peers_responded);
2051 GNUNET_free (source_info);
2055 * Main function that handles whether or not to route a result
2056 * message to other peers, or to send to our local client.
2058 * @param msg the result message to be routed
2059 * @param msg_ctx context of the message we are routing
2061 * @return the number of peers the message was routed to,
2062 * GNUNET_SYSERR on failure
2065 route_result_message (struct GNUNET_MessageHeader *msg,
2066 struct DHT_MessageContext *msg_ctx)
2068 struct GNUNET_PeerIdentity new_peer;
2069 struct DHTQueryRecord *record;
2070 struct DHTRouteSource *pos;
2071 struct PeerInfo *peer_info;
2072 const struct GNUNET_MessageHeader *hello_msg;
2074 increment_stats (STAT_RESULTS);
2076 * If a find peer result message is received and contains a valid
2077 * HELLO for another peer, offer it to the transport service.
2079 if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DHT_FIND_PEER_RESULT)
2081 if (ntohs (msg->size) <= sizeof (struct GNUNET_MessageHeader))
2082 GNUNET_break_op (0);
2084 hello_msg = &msg[1];
2085 if ((ntohs (hello_msg->type) != GNUNET_MESSAGE_TYPE_HELLO)
2086 || (GNUNET_SYSERR ==
2087 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *)
2088 hello_msg, &new_peer)))
2090 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2091 "%s:%s Received non-HELLO message type in find peer result message!\n",
2092 my_short_id, "DHT");
2093 GNUNET_break_op (0);
2096 else /* We have a valid hello, and peer id stored in new_peer */
2098 find_peer_context.count++;
2099 increment_stats (STAT_FIND_PEER_REPLY);
2100 if (GNUNET_YES == consider_peer (&new_peer))
2102 increment_stats (STAT_HELLOS_PROVIDED);
2103 GNUNET_TRANSPORT_offer_hello (transport_handle, hello_msg);
2104 GNUNET_CORE_peer_request_connect (coreAPI,
2105 GNUNET_TIME_relative_multiply
2106 (GNUNET_TIME_UNIT_SECONDS, 5),
2107 &new_peer, NULL, NULL);
2112 if (malicious_dropper == GNUNET_YES)
2116 GNUNET_CONTAINER_multihashmap_get (forward_list.hashmap, &msg_ctx->key);
2118 if (record == NULL) /* No record of this message! */
2121 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2122 "`%s:%s': Have no record of response key %s uid %llu\n",
2123 my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key),
2124 msg_ctx->unique_id);
2126 #if DEBUG_DHT_ROUTING
2127 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2129 dhtlog_handle->insert_route (NULL,
2135 &msg_ctx->key, msg_ctx->peer, NULL);
2138 if (msg_ctx->bloom != NULL)
2140 GNUNET_CONTAINER_bloomfilter_free (msg_ctx->bloom);
2141 msg_ctx->bloom = NULL;
2149 #if STRICT_FORWARDING
2150 if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DHT_FIND_PEER_RESULT) /* If we have already forwarded this peer id, don't do it again! */
2153 GNUNET_CONTAINER_bloomfilter_test (pos->find_peers_responded,
2154 &new_peer.hashPubKey))
2157 ("# find peer responses NOT forwarded (bloom match)");
2162 GNUNET_CONTAINER_bloomfilter_add (pos->find_peers_responded,
2163 &new_peer.hashPubKey);
2167 if (0 == memcmp (&pos->source, &my_identity, sizeof (struct GNUNET_PeerIdentity))) /* Local client (or DHT) initiated request! */
2170 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2171 "`%s:%s': Sending response key %s uid %llu to client\n",
2172 my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key),
2173 msg_ctx->unique_id);
2175 #if DEBUG_DHT_ROUTING
2176 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2178 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id,
2179 DHTLOG_RESULT, msg_ctx->hop_count,
2180 GNUNET_YES, &my_identity,
2181 &msg_ctx->key, msg_ctx->peer,
2185 increment_stats (STAT_RESULTS_TO_CLIENT);
2186 if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DHT_GET_RESULT)
2187 increment_stats (STAT_GET_REPLY);
2189 send_reply_to_client (pos->client, msg,
2190 msg_ctx->unique_id, &msg_ctx->key);
2192 else /* Send to peer */
2194 peer_info = find_peer_by_id (&pos->source);
2195 if (peer_info == NULL) /* Didn't find the peer in our routing table, perhaps peer disconnected! */
2201 if (msg_ctx->bloom == NULL)
2203 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
2205 GNUNET_CONTAINER_bloomfilter_add (msg_ctx->bloom,
2206 &my_identity.hashPubKey);
2208 GNUNET_CONTAINER_bloomfilter_test (msg_ctx->bloom,
2209 &peer_info->id.hashPubKey)))
2212 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2213 "`%s:%s': Forwarding response key %s uid %llu to peer %s\n",
2214 my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key),
2215 msg_ctx->unique_id, GNUNET_i2s (&peer_info->id));
2217 #if DEBUG_DHT_ROUTING
2218 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2220 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id,
2223 GNUNET_NO, &my_identity,
2224 &msg_ctx->key, msg_ctx->peer,
2228 forward_result_message (msg, peer_info, msg_ctx);
2229 /* Try removing forward entries after sending once, only allows ONE response per request */
2230 if (pos->delete_task != GNUNET_SCHEDULER_NO_TASK)
2232 GNUNET_SCHEDULER_cancel (pos->delete_task);
2234 GNUNET_SCHEDULER_add_now (&remove_forward_entry, pos);
2240 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2241 "`%s:%s': NOT Forwarding response (bloom match) key %s uid %llu to peer %s\n",
2242 my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key),
2243 msg_ctx->unique_id, GNUNET_i2s (&peer_info->id));
2249 if (msg_ctx->bloom != NULL)
2251 GNUNET_CONTAINER_bloomfilter_free (msg_ctx->bloom);
2252 msg_ctx->bloom = NULL;
2258 * Iterator for local get request results,
2260 * @param cls closure for iterator, a DatacacheGetContext
2261 * @param exp when does this value expire?
2262 * @param key the key this data is stored under
2263 * @param size the size of the data identified by key
2264 * @param data the actual data
2265 * @param type the type of the data
2267 * @return GNUNET_OK to continue iteration, anything else
2268 * to stop iteration.
2271 datacache_get_iterator (void *cls,
2272 struct GNUNET_TIME_Absolute exp,
2273 const GNUNET_HashCode * key,
2274 size_t size, const char *data,
2275 enum GNUNET_BLOCK_Type type)
2277 struct DHT_MessageContext *msg_ctx = cls;
2278 struct DHT_MessageContext *new_msg_ctx;
2279 struct GNUNET_DHT_GetResultMessage *get_result;
2280 enum GNUNET_BLOCK_EvaluationResult eval;
2283 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2284 "`%s:%s': Received `%s' response from datacache\n", my_short_id,
2287 eval = GNUNET_BLOCK_evaluate (block_context,
2291 msg_ctx->reply_bf_mutator,
2293 msg_ctx->xquery_size, data, size);
2296 case GNUNET_BLOCK_EVALUATION_OK_LAST:
2297 msg_ctx->do_forward = GNUNET_NO;
2298 case GNUNET_BLOCK_EVALUATION_OK_MORE:
2299 new_msg_ctx = GNUNET_malloc (sizeof (struct DHT_MessageContext));
2300 memcpy (new_msg_ctx, msg_ctx, sizeof (struct DHT_MessageContext));
2302 GNUNET_malloc (sizeof (struct GNUNET_DHT_GetResultMessage) + size);
2303 get_result->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_GET_RESULT);
2304 get_result->header.size =
2305 htons (sizeof (struct GNUNET_DHT_GetResultMessage) + size);
2306 get_result->expiration = GNUNET_TIME_absolute_hton (exp);
2307 get_result->type = htons (type);
2308 memcpy (&get_result[1], data, size);
2309 new_msg_ctx->peer = &my_identity;
2310 new_msg_ctx->bloom =
2311 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K);
2312 new_msg_ctx->hop_count = 0;
2313 new_msg_ctx->importance = DHT_DEFAULT_P2P_IMPORTANCE + 2; /* Make result routing a higher priority */
2314 new_msg_ctx->timeout = DHT_DEFAULT_P2P_TIMEOUT;
2315 increment_stats (STAT_GET_RESPONSE_START);
2316 route_result_message (&get_result->header, new_msg_ctx);
2317 GNUNET_free (new_msg_ctx);
2318 GNUNET_free (get_result);
2320 case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE:
2322 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2323 "`%s:%s': Duplicate block error\n", my_short_id, "DHT");
2326 case GNUNET_BLOCK_EVALUATION_RESULT_INVALID:
2328 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2329 "`%s:%s': Invalid request error\n", my_short_id, "DHT");
2332 case GNUNET_BLOCK_EVALUATION_REQUEST_VALID:
2334 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2335 "`%s:%s': Valid request, no results.\n", my_short_id,
2340 case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID:
2341 GNUNET_break_op (0);
2342 msg_ctx->do_forward = GNUNET_NO;
2344 case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED:
2346 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2347 "`%s:%s': Unsupported block type (%u) in response!\n",
2348 my_short_id, "DHT", type);
2350 /* msg_ctx->do_forward = GNUNET_NO; // not sure... */
2358 * Main function that handles whether or not to route a message to other
2361 * @param msg the message to be routed
2362 * @param msg_ctx the context containing all pertinent information about the message
2365 route_message (const struct GNUNET_MessageHeader *msg,
2366 struct DHT_MessageContext *msg_ctx);
2370 * Server handler for all dht get requests, look for data,
2371 * if found, send response either to clients or other peers.
2373 * @param msg the actual get message
2374 * @param msg_ctx struct containing pertinent information about the get request
2376 * @return number of items found for GET request
2379 handle_dht_get (const struct GNUNET_MessageHeader *msg,
2380 struct DHT_MessageContext *msg_ctx)
2382 const struct GNUNET_DHT_GetMessage *get_msg;
2385 unsigned int results;
2387 enum GNUNET_BLOCK_Type type;
2389 msize = ntohs (msg->size);
2390 if (msize < sizeof (struct GNUNET_DHT_GetMessage))
2395 get_msg = (const struct GNUNET_DHT_GetMessage *) msg;
2396 bf_size = ntohs (get_msg->bf_size);
2397 msg_ctx->xquery_size = ntohs (get_msg->xquery_size);
2398 msg_ctx->reply_bf_mutator = get_msg->bf_mutator; /* FIXME: ntohl? */
2400 sizeof (struct GNUNET_DHT_GetMessage) + bf_size + msg_ctx->xquery_size)
2405 end = (const char *) &get_msg[1];
2406 if (msg_ctx->xquery_size == 0)
2408 msg_ctx->xquery = NULL;
2412 msg_ctx->xquery = (const void *) end;
2413 end += msg_ctx->xquery_size;
2417 msg_ctx->reply_bf = NULL;
2421 msg_ctx->reply_bf = GNUNET_CONTAINER_bloomfilter_init (end,
2423 GNUNET_DHT_GET_BLOOMFILTER_K);
2425 type = (enum GNUNET_BLOCK_Type) ntohl (get_msg->type);
2427 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2428 "`%s:%s': Received `%s' request, message type %u, key %s, uid %llu\n",
2431 type, GNUNET_h2s (&msg_ctx->key), msg_ctx->unique_id);
2433 increment_stats (STAT_GETS);
2436 if (type == GNUNET_BLOCK_DHT_MALICIOUS_MESSAGE_TYPE)
2438 GNUNET_CONTAINER_bloomfilter_free (msg_ctx->reply_bf);
2442 msg_ctx->do_forward = GNUNET_YES;
2443 if (datacache != NULL)
2445 = GNUNET_DATACACHE_get (datacache,
2446 &msg_ctx->key, type,
2447 &datacache_get_iterator, msg_ctx);
2449 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2450 "`%s:%s': Found %d results for `%s' request uid %llu\n",
2451 my_short_id, "DHT", results, "GET", msg_ctx->unique_id);
2455 #if DEBUG_DHT_ROUTING
2456 if ((debug_routes) && (dhtlog_handle != NULL))
2458 dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_GET,
2459 msg_ctx->hop_count, GNUNET_YES,
2460 &my_identity, &msg_ctx->key);
2463 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2465 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE,
2466 msg_ctx->hop_count, GNUNET_YES,
2467 &my_identity, &msg_ctx->key,
2468 msg_ctx->peer, NULL);
2474 /* check query valid */
2475 if (GNUNET_BLOCK_EVALUATION_REQUEST_INVALID
2476 == GNUNET_BLOCK_evaluate (block_context,
2480 msg_ctx->reply_bf_mutator,
2482 msg_ctx->xquery_size, NULL, 0))
2484 GNUNET_break_op (0);
2485 msg_ctx->do_forward = GNUNET_NO;
2489 if (msg_ctx->hop_count == 0) /* Locally initiated request */
2491 #if DEBUG_DHT_ROUTING
2492 if ((debug_routes) && (dhtlog_handle != NULL))
2494 dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_GET,
2495 msg_ctx->hop_count, GNUNET_NO,
2496 &my_identity, &msg_ctx->key);
2500 if (msg_ctx->do_forward == GNUNET_YES)
2501 route_message (msg, msg_ctx);
2502 GNUNET_CONTAINER_bloomfilter_free (msg_ctx->reply_bf);
2507 remove_recent_find_peer (void *cls,
2508 const struct GNUNET_SCHEDULER_TaskContext *tc)
2510 GNUNET_HashCode *key = cls;
2512 GNUNET_assert (GNUNET_YES ==
2513 GNUNET_CONTAINER_multihashmap_remove
2514 (recent_find_peer_requests, key, NULL));
2519 * Server handler for initiating local dht find peer requests
2521 * @param find_msg the actual find peer message
2522 * @param msg_ctx struct containing pertinent information about the request
2526 handle_dht_find_peer (const struct GNUNET_MessageHeader *find_msg,
2527 struct DHT_MessageContext *msg_ctx)
2529 struct GNUNET_MessageHeader *find_peer_result;
2530 struct GNUNET_DHT_FindPeerMessage *find_peer_message;
2531 struct DHT_MessageContext *new_msg_ctx;
2532 struct GNUNET_CONTAINER_BloomFilter *incoming_bloom;
2535 GNUNET_HashCode *recent_hash;
2536 struct GNUNET_MessageHeader *other_hello;
2537 size_t other_hello_size;
2538 struct GNUNET_PeerIdentity peer_id;
2540 find_peer_message = (struct GNUNET_DHT_FindPeerMessage *) find_msg;
2541 GNUNET_break_op (ntohs (find_msg->size) >=
2542 (sizeof (struct GNUNET_DHT_FindPeerMessage)));
2543 if (ntohs (find_msg->size) < sizeof (struct GNUNET_DHT_FindPeerMessage))
2546 other_hello_size = 0;
2547 if (ntohs (find_msg->size) > sizeof (struct GNUNET_DHT_FindPeerMessage))
2550 ntohs (find_msg->size) - sizeof (struct GNUNET_DHT_FindPeerMessage);
2551 other_hello = GNUNET_malloc (other_hello_size);
2552 memcpy (other_hello, &find_peer_message[1], other_hello_size);
2553 if ((GNUNET_HELLO_size ((struct GNUNET_HELLO_Message *) other_hello) ==
2556 GNUNET_HELLO_get_id ((struct GNUNET_HELLO_Message *)
2557 other_hello, &peer_id)))
2559 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2560 "Received invalid HELLO message in find peer request!\n");
2561 GNUNET_free (other_hello);
2564 #if FIND_PEER_WITH_HELLO
2565 if (GNUNET_YES == consider_peer (&peer_id))
2567 increment_stats (STAT_HELLOS_PROVIDED);
2568 GNUNET_TRANSPORT_offer_hello (transport_handle, other_hello);
2569 GNUNET_CORE_peer_request_connect (coreAPI,
2570 GNUNET_TIME_relative_multiply
2571 (GNUNET_TIME_UNIT_SECONDS, 5),
2572 &peer_id, NULL, NULL);
2573 route_message (find_msg, msg_ctx);
2574 GNUNET_free (other_hello);
2577 else /* We don't want this peer! */
2579 route_message (find_msg, msg_ctx);
2580 GNUNET_free (other_hello);
2587 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2588 "`%s:%s': Received `%s' request from client, key %s (msg size %d, we expected %d)\n",
2589 my_short_id, "DHT", "FIND PEER", GNUNET_h2s (&msg_ctx->key),
2590 ntohs (find_msg->size), sizeof (struct GNUNET_MessageHeader));
2592 if (my_hello == NULL)
2595 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2596 "`%s': Our HELLO is null, can't return.\n", "DHT");
2598 GNUNET_free_non_null (other_hello);
2599 route_message (find_msg, msg_ctx);
2604 GNUNET_CONTAINER_bloomfilter_init (find_peer_message->bloomfilter,
2605 DHT_BLOOM_SIZE, DHT_BLOOM_K);
2607 GNUNET_CONTAINER_bloomfilter_test (incoming_bloom,
2608 &my_identity.hashPubKey))
2610 increment_stats (STAT_BLOOM_FIND_PEER);
2611 GNUNET_CONTAINER_bloomfilter_free (incoming_bloom);
2612 GNUNET_free_non_null (other_hello);
2613 route_message (find_msg, msg_ctx);
2614 return; /* We match the bloomfilter, do not send a response to this peer (they likely already know us!) */
2616 GNUNET_CONTAINER_bloomfilter_free (incoming_bloom);
2618 #if RESTRICT_FIND_PEER
2621 * Ignore any find peer requests from a peer we have seen very recently.
2623 if (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains (recent_find_peer_requests, &msg_ctx->key)) /* We have recently responded to a find peer request for this peer! */
2625 increment_stats ("# dht find peer requests ignored (recently seen!)");
2626 GNUNET_free_non_null (other_hello);
2631 * Use this check to only allow the peer to respond to find peer requests if
2632 * it would be beneficial to have the requesting peer in this peers routing
2633 * table. Can be used to thwart peers flooding the network with find peer
2634 * requests that we don't care about. However, if a new peer is joining
2635 * the network and has no other peers this is a problem (assume all buckets
2636 * full, no one will respond!).
2638 memcpy (&peer_id.hashPubKey, &msg_ctx->key, sizeof (GNUNET_HashCode));
2639 if (GNUNET_NO == consider_peer (&peer_id))
2641 increment_stats ("# dht find peer requests ignored (do not need!)");
2642 GNUNET_free_non_null (other_hello);
2643 route_message (find_msg, msg_ctx);
2648 recent_hash = GNUNET_malloc (sizeof (GNUNET_HashCode));
2649 memcpy (recent_hash, &msg_ctx->key, sizeof (GNUNET_HashCode));
2650 if (GNUNET_SYSERR !=
2651 GNUNET_CONTAINER_multihashmap_put (recent_find_peer_requests,
2652 &msg_ctx->key, NULL,
2653 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
2655 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2656 "Adding recent remove task for key `%s`!\n",
2657 GNUNET_h2s (&msg_ctx->key));
2658 /* Only add a task if there wasn't one for this key already! */
2659 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_relative_multiply
2660 (GNUNET_TIME_UNIT_SECONDS, 30),
2661 &remove_recent_find_peer, recent_hash);
2665 GNUNET_free (recent_hash);
2666 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2667 "Received duplicate find peer request too soon!\n");
2670 /* Simplistic find_peer functionality, always return our hello */
2671 hello_size = ntohs (my_hello->size);
2672 tsize = hello_size + sizeof (struct GNUNET_MessageHeader);
2674 if (tsize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
2676 GNUNET_break_op (0);
2677 GNUNET_free_non_null (other_hello);
2681 find_peer_result = GNUNET_malloc (tsize);
2682 find_peer_result->type = htons (GNUNET_MESSAGE_TYPE_DHT_FIND_PEER_RESULT);
2683 find_peer_result->size = htons (tsize);
2684 memcpy (&find_peer_result[1], my_hello, hello_size);
2686 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2687 "`%s': Sending hello size %d to requesting peer.\n",
2690 new_msg_ctx = GNUNET_malloc (sizeof (struct DHT_MessageContext));
2691 memcpy (new_msg_ctx, msg_ctx, sizeof (struct DHT_MessageContext));
2692 new_msg_ctx->peer = &my_identity;
2693 new_msg_ctx->bloom =
2694 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K);
2695 new_msg_ctx->hop_count = 0;
2696 new_msg_ctx->importance = DHT_DEFAULT_P2P_IMPORTANCE + 2; /* Make find peer requests a higher priority */
2697 new_msg_ctx->timeout = DHT_DEFAULT_P2P_TIMEOUT;
2698 increment_stats (STAT_FIND_PEER_ANSWER);
2699 route_result_message (find_peer_result, new_msg_ctx);
2700 GNUNET_free (new_msg_ctx);
2701 #if DEBUG_DHT_ROUTING
2702 if ((debug_routes) && (dhtlog_handle != NULL))
2704 dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_FIND_PEER,
2705 msg_ctx->hop_count, GNUNET_YES,
2706 &my_identity, &msg_ctx->key);
2709 GNUNET_free_non_null (other_hello);
2710 GNUNET_free (find_peer_result);
2711 route_message (find_msg, msg_ctx);
2715 * Task used to republish data.
2716 * Forward declaration; function call loop.
2718 * @param cls closure (a struct RepublishContext)
2719 * @param tc runtime context for this task
2722 republish_content (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
2725 * Server handler for initiating local dht put requests
2727 * @param msg the actual put message
2728 * @param msg_ctx struct containing pertinent information about the request
2731 handle_dht_put (const struct GNUNET_MessageHeader *msg,
2732 struct DHT_MessageContext *msg_ctx)
2734 const struct GNUNET_DHT_PutMessage *put_msg;
2735 enum GNUNET_BLOCK_Type put_type;
2738 struct RepublishContext *put_context;
2739 GNUNET_HashCode key;
2741 GNUNET_assert (ntohs (msg->size) >= sizeof (struct GNUNET_DHT_PutMessage));
2744 put_msg = (const struct GNUNET_DHT_PutMessage *) msg;
2745 put_type = (enum GNUNET_BLOCK_Type) ntohl (put_msg->type);
2747 if (put_type == GNUNET_BLOCK_DHT_MALICIOUS_MESSAGE_TYPE)
2749 #if DEBUG_DHT_ROUTING
2750 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2752 /** Log routes that die due to high load! */
2753 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE,
2754 msg_ctx->hop_count, GNUNET_SYSERR,
2755 &my_identity, &msg_ctx->key,
2756 msg_ctx->peer, NULL);
2763 ntohs (put_msg->header.size) - sizeof (struct GNUNET_DHT_PutMessage);
2765 GNUNET_BLOCK_get_key (block_context, put_type, &put_msg[1], data_size,
2767 if (GNUNET_NO == ret)
2769 #if DEBUG_DHT_ROUTING
2770 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2772 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE,
2773 msg_ctx->hop_count, GNUNET_SYSERR,
2774 &my_identity, &msg_ctx->key,
2775 msg_ctx->peer, NULL);
2779 GNUNET_break_op (0);
2782 if ((GNUNET_YES == ret) &&
2783 (0 != memcmp (&key, &msg_ctx->key, sizeof (GNUNET_HashCode))))
2785 #if DEBUG_DHT_ROUTING
2786 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2788 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE,
2789 msg_ctx->hop_count, GNUNET_SYSERR,
2790 &my_identity, &msg_ctx->key,
2791 msg_ctx->peer, NULL);
2794 /* invalid wrapper: key mismatch! */
2795 GNUNET_break_op (0);
2798 /* ret == GNUNET_SYSERR means that there is no known relationship between
2799 data and the key, so we cannot check it */
2801 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2802 "`%s:%s': Received `%s' request (inserting data!), message type %d, key %s, uid %llu\n",
2803 my_short_id, "DHT", "PUT", put_type, GNUNET_h2s (&msg_ctx->key),
2804 msg_ctx->unique_id);
2806 #if DEBUG_DHT_ROUTING
2807 if (msg_ctx->hop_count == 0) /* Locally initiated request */
2809 if ((debug_routes) && (dhtlog_handle != NULL))
2811 dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_PUT,
2812 msg_ctx->hop_count, GNUNET_NO,
2813 &my_identity, &msg_ctx->key);
2818 if (msg_ctx->closest != GNUNET_YES)
2820 route_message (msg, msg_ctx);
2825 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2826 "`%s:%s': Received `%s' request (inserting data!), message type %d, key %s, uid %llu\n",
2827 my_short_id, "DHT", "PUT", put_type, GNUNET_h2s (&msg_ctx->key),
2828 msg_ctx->unique_id);
2831 #if DEBUG_DHT_ROUTING
2832 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2834 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE,
2835 msg_ctx->hop_count, GNUNET_YES,
2836 &my_identity, &msg_ctx->key, msg_ctx->peer,
2840 if ((debug_routes) && (dhtlog_handle != NULL))
2842 dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_PUT,
2843 msg_ctx->hop_count, GNUNET_YES,
2844 &my_identity, &msg_ctx->key);
2848 increment_stats (STAT_PUTS_INSERTED);
2849 if (datacache != NULL)
2851 ret = GNUNET_DATACACHE_put (datacache, &msg_ctx->key, data_size,
2852 (char *) &put_msg[1], put_type,
2853 GNUNET_TIME_absolute_ntoh
2854 (put_msg->expiration));
2856 if ((ret == GNUNET_YES) && (do_republish == GNUNET_YES))
2858 put_context = GNUNET_malloc (sizeof (struct RepublishContext));
2859 memcpy (&put_context->key, &msg_ctx->key, sizeof (GNUNET_HashCode));
2860 put_context->type = put_type;
2861 GNUNET_SCHEDULER_add_delayed (dht_republish_frequency,
2862 &republish_content, put_context);
2866 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2867 "`%s:%s': %s request received, but have no datacache!\n",
2868 my_short_id, "DHT", "PUT");
2870 if (stop_on_closest == GNUNET_NO)
2871 route_message (msg, msg_ctx);
2875 * Estimate the diameter of the network based
2876 * on how many buckets are currently in use.
2877 * Concept here is that the diameter of the network
2878 * is roughly the distance a message must travel in
2879 * order to reach its intended destination. Since
2880 * at each hop we expect to get one bit closer, and
2881 * we have one bit per bucket, the number of buckets
2882 * in use should be the largest number of hops for
2883 * a successful message. (of course, this assumes we
2884 * know all peers in the network!)
2886 * @return ballpark diameter figure
2889 estimate_diameter ()
2891 return MAX_BUCKETS - lowest_bucket;
2895 * To how many peers should we (on average)
2896 * forward the request to obtain the desired
2897 * target_replication count (on average).
2899 * returns: target_replication / (est. hops) + (target_replication * hop_count)
2900 * where est. hops is typically 2 * the routing table depth
2902 * @param hop_count number of hops the message has traversed
2903 * @param target_replication the number of total paths desired
2905 * @return Some number of peers to forward the message to
2908 get_forward_count (unsigned int hop_count, size_t target_replication)
2910 uint32_t random_value;
2911 unsigned int forward_count;
2913 unsigned int diameter;
2915 diameter = estimate_diameter ();
2917 if (GNUNET_NO == use_max_hops)
2918 max_hops = (diameter + 1) * 2;
2921 * If we are behaving in strict kademlia mode, send multiple initial requests,
2922 * but then only send to 1 or 0 peers based strictly on the number of hops.
2924 if (strict_kademlia == GNUNET_YES)
2927 return kademlia_replication;
2928 else if (hop_count < max_hops)
2934 /* FIXME: the smaller we think the network is the more lenient we should be for
2935 * routing right? The estimation below only works if we think we have reasonably
2936 * full routing tables, which for our RR topologies may not be the case!
2938 if (hop_count > max_hops)
2941 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2942 "`%s:%s': Hop count too high (est %d, lowest %d), NOT Forwarding request\n",
2943 my_short_id, "DHT", estimate_diameter (), lowest_bucket);
2951 target_replication / (diameter +
2952 ((float) target_replication * hop_count));
2953 if (target_value > 1)
2955 /* Set forward count to floor of target_value */
2956 forward_count = (unsigned int) target_value;
2957 /* Subtract forward_count (floor) from target_value (yields value between 0 and 1) */
2958 target_value = target_value - forward_count;
2962 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_STRONG,
2965 if (random_value < (target_value * (unsigned int) -1))
2968 return forward_count;
2972 * Check whether my identity is closer than any known peers.
2973 * If a non-null bloomfilter is given, check if this is the closest
2974 * peer that hasn't already been routed to.
2976 * @param target hash code to check closeness to
2977 * @param bloom bloomfilter, exclude these entries from the decision
2979 * Return GNUNET_YES if node location is closest, GNUNET_NO
2983 am_closest_peer (const GNUNET_HashCode * target,
2984 struct GNUNET_CONTAINER_BloomFilter *bloom)
2990 struct PeerInfo *pos;
2991 unsigned int my_distance;
2993 if (0 == memcmp (&my_identity.hashPubKey, target, sizeof (GNUNET_HashCode)))
2996 bucket_num = find_current_bucket (target);
2998 bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, target);
2999 my_distance = distance (&my_identity.hashPubKey, target);
3000 pos = k_buckets[bucket_num].head;
3002 while ((pos != NULL) && (count < bucket_size))
3006 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)))
3009 continue; /* Skip already checked entries */
3013 GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey, target);
3014 if (other_bits > bits)
3016 else if (other_bits == bits) /* We match the same number of bits */
3018 if (strict_kademlia != GNUNET_YES) /* Return that we at as close as any other peer */
3020 else if (distance (&pos->id.hashPubKey, target) < my_distance) /* Check all known peers, only return if we are the true closest */
3026 /* No peers closer, we are the closest! */
3032 * Return this peers adjusted value based on the convergence
3033 * function chosen. This is the key function for randomized
3034 * routing decisions.
3036 * @param target the key of the request
3037 * @param peer the peer we would like the value of
3038 * @param hops number of hops this message has already traveled
3040 * @return bit distance from target to peer raised to an exponent
3041 * adjusted based on the current routing convergence algorithm
3044 static unsigned long long
3045 converge_distance (const GNUNET_HashCode * target,
3046 struct PeerInfo *peer, unsigned int hops)
3048 unsigned long long ret;
3049 unsigned int other_matching_bits;
3050 double base_converge_modifier = .1; /* Value that "looks" good (when plotted), have to start somewhere */
3051 double temp_modifier;
3057 curr_max_hops = max_hops;
3059 curr_max_hops = (estimate_diameter () + 1) * 2;
3061 if (converge_modifier > 0)
3062 temp_modifier = converge_modifier * base_converge_modifier;
3065 temp_modifier = base_converge_modifier;
3066 base_converge_modifier = 0.0;
3069 GNUNET_assert (temp_modifier > 0);
3071 other_matching_bits =
3072 GNUNET_CRYPTO_hash_matching_bits (target, &peer->id.hashPubKey);
3074 switch (converge_option)
3076 case DHT_CONVERGE_RANDOM:
3077 return 1; /* Always return 1, choose equally among all peers */
3078 case DHT_CONVERGE_LINEAR:
3079 calc_value = hops * curr_max_hops * temp_modifier;
3081 case DHT_CONVERGE_SQUARE:
3083 * Simple square based curve.
3086 (sqrt (hops) / sqrt (curr_max_hops)) * (curr_max_hops /
3090 case DHT_CONVERGE_EXPONENTIAL:
3092 * Simple exponential curve.
3094 if (base_converge_modifier > 0)
3095 calc_value = (temp_modifier * hops * hops) / curr_max_hops;
3097 calc_value = (hops * hops) / curr_max_hops;
3099 case DHT_CONVERGE_BINARY:
3101 * If below the cutoff, route randomly (return 1),
3102 * If above the cutoff, return the maximum possible
3103 * value first (always route to closest, because
3107 if (hops >= converge_modifier) /* Past cutoff */
3116 /* Take the log (base e) of the number of bits matching the other peer */
3117 exponent = log (other_matching_bits);
3119 /* Check if we would overflow; our largest possible value is 2^64 approx. e^44.361419555836498 */
3120 if (exponent * calc_value >= 44.361419555836498)
3123 /* Clear errno and all math exceptions */
3125 feclearexcept (FE_ALL_EXCEPT);
3126 ret = (unsigned long long) pow (other_matching_bits, calc_value);
3127 if ((errno != 0) || fetestexcept (FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW |
3130 if (0 != fetestexcept (FE_OVERFLOW))
3131 GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "FE_OVERFLOW\n");
3132 if (0 != fetestexcept (FE_INVALID))
3133 GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "FE_INVALID\n");
3134 if (0 != fetestexcept (FE_UNDERFLOW))
3135 GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "FE_UNDERFLOW\n");
3143 * Comparison function for two struct PeerInfo's
3144 * which have already had their matching bits to
3145 * some target calculated.
3147 * @param p1 a pointer pointer to a struct PeerInfo
3148 * @param p2 a pointer pointer to a struct PeerInfo
3150 * @return 0 if equidistant to target,
3151 * -1 if p1 is closer,
3155 compare_peers (const void *p1, const void *p2)
3157 struct PeerInfo **first = (struct PeerInfo **) p1;
3158 struct PeerInfo **second = (struct PeerInfo **) p2;
3160 if ((*first)->matching_bits > (*second)->matching_bits)
3162 if ((*first)->matching_bits < (*second)->matching_bits)
3170 * Select a peer from the routing table that would be a good routing
3171 * destination for sending a message for "target". The resulting peer
3172 * must not be in the set of blocked peers.<p>
3174 * Note that we should not ALWAYS select the closest peer to the
3175 * target, peers further away from the target should be chosen with
3176 * exponentially declining probability.
3178 * @param target the key we are selecting a peer to route to
3179 * @param bloom a bloomfilter containing entries this request has seen already
3181 * @return Peer to route to, or NULL on error
3183 static struct PeerInfo *
3184 select_peer (const GNUNET_HashCode * target,
3185 struct GNUNET_CONTAINER_BloomFilter *bloom, unsigned int hops)
3190 unsigned int offset;
3191 unsigned int my_matching_bits;
3193 struct PeerInfo *pos;
3194 struct PeerInfo *sorted_closest[bucket_size];
3195 unsigned long long temp_converge_distance;
3196 unsigned long long total_distance;
3197 unsigned long long selected;
3199 unsigned long long stats_total_distance;
3203 unsigned int distance;
3204 unsigned int largest_distance;
3205 struct PeerInfo *chosen;
3208 GNUNET_CRYPTO_hash_matching_bits (target, &my_identity.hashPubKey);
3211 /** If we are doing kademlia routing, or converge is binary (saves some cycles) */
3212 if ((strict_kademlia == GNUNET_YES) ||
3213 ((converge_option == DHT_CONVERGE_BINARY)
3214 && (hops >= converge_modifier)))
3216 largest_distance = 0;
3218 for (bc = lowest_bucket; bc < MAX_BUCKETS; bc++)
3220 pos = k_buckets[bc].head;
3222 while ((pos != NULL) && (count < bucket_size))
3224 /* If we are doing strict Kademlia routing, then checking the bloomfilter is basically cheating! */
3226 GNUNET_CONTAINER_bloomfilter_test (bloom,
3227 &pos->id.hashPubKey))
3229 distance = inverse_distance (target, &pos->id.hashPubKey);
3230 if (distance > largest_distance)
3233 largest_distance = distance;
3241 if ((largest_distance > 0) && (chosen != NULL))
3243 GNUNET_CONTAINER_bloomfilter_add (bloom, &chosen->id.hashPubKey);
3254 /* Three steps: order peers in closest bucket (most matching bits).
3255 * Then go over all LOWER buckets (matching same bits we do)
3256 * Then go over all HIGHER buckets (matching less then we do)
3259 closest_bucket = find_current_bucket (target);
3260 GNUNET_assert (closest_bucket >= lowest_bucket);
3261 pos = k_buckets[closest_bucket].head;
3263 offset = 0; /* Need offset as well as count in case peers are bloomfiltered */
3264 memset (sorted_closest, 0, sizeof (sorted_closest));
3265 /* Put any peers in the closest bucket in the sorting array */
3266 while ((pos != NULL) && (count < bucket_size))
3269 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey))
3273 continue; /* Ignore bloomfiltered peers */
3275 pos->matching_bits =
3276 GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey, target);
3277 sorted_closest[offset] = pos;
3283 /* Sort the peers in descending order */
3284 qsort (&sorted_closest[0], offset, sizeof (struct PeerInfo *),
3287 /* Put the sorted closest peers into the possible bins first, in case of overflow. */
3288 for (i = 0; i < offset; i++)
3290 temp_converge_distance =
3291 converge_distance (target, sorted_closest[i], hops);
3293 GNUNET_CONTAINER_bloomfilter_test (bloom,
3294 &sorted_closest[i]->id.
3296 break; /* Ignore bloomfiltered peers */
3297 if ((temp_converge_distance <= ULLONG_MAX) && (total_distance + temp_converge_distance > total_distance)) /* Handle largest case and overflow */
3298 total_distance += temp_converge_distance;
3300 break; /* overflow case */
3303 /* Now handle peers in lower buckets (matches same # of bits as target) */
3304 for (bc = lowest_bucket; bc < closest_bucket; bc++)
3306 pos = k_buckets[bc].head;
3308 while ((pos != NULL) && (count < bucket_size))
3311 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey))
3315 continue; /* Ignore bloomfiltered peers */
3317 temp_converge_distance = converge_distance (target, pos, hops);
3318 if ((temp_converge_distance <= ULLONG_MAX) && (total_distance + temp_converge_distance > total_distance)) /* Handle largest case and overflow */
3319 total_distance += temp_converge_distance;
3321 break; /* overflow case */
3327 /* Now handle all the further away peers */
3328 for (bc = closest_bucket + 1; bc < MAX_BUCKETS; bc++)
3330 pos = k_buckets[bc].head;
3332 while ((pos != NULL) && (count < bucket_size))
3335 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey))
3339 continue; /* Ignore bloomfiltered peers */
3341 temp_converge_distance = converge_distance (target, pos, hops);
3342 if ((temp_converge_distance <= ULLONG_MAX) && (total_distance + temp_converge_distance > total_distance)) /* Handle largest case and overflow */
3343 total_distance += temp_converge_distance;
3345 break; /* overflow case */
3351 if (total_distance == 0) /* No peers to select from! */
3353 increment_stats ("# failed to select peer");
3357 #if DEBUG_DHT_ROUTING > 1
3360 /* Put the sorted closest peers into the possible bins first, in case of overflow. */
3361 stats_total_distance = 0;
3362 for (i = 0; i < offset; i++)
3365 GNUNET_CONTAINER_bloomfilter_test (bloom,
3366 &sorted_closest[i]->id.
3368 break; /* Ignore bloomfiltered peers */
3369 temp_converge_distance =
3370 converge_distance (target, sorted_closest[i], hops);
3371 if ((temp_converge_distance <= ULLONG_MAX) && (stats_total_distance + temp_converge_distance > stats_total_distance)) /* Handle largest case and overflow */
3372 stats_total_distance += temp_converge_distance;
3374 break; /* overflow case */
3375 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3376 "Choose %d matching bits (%d bits match me) (%.2f percent) converge ret %llu\n",
3377 GNUNET_CRYPTO_hash_matching_bits (&sorted_closest[i]->id.
3378 hashPubKey, target),
3379 GNUNET_CRYPTO_hash_matching_bits (&sorted_closest[i]->id.
3381 &my_identity.hashPubKey),
3382 (temp_converge_distance / (double) total_distance) * 100,
3383 temp_converge_distance);
3386 /* Now handle peers in lower buckets (matches same # of bits as target) */
3387 for (bc = lowest_bucket; bc < closest_bucket; bc++)
3389 pos = k_buckets[bc].head;
3391 while ((pos != NULL) && (count < bucket_size))
3394 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey))
3398 continue; /* Ignore bloomfiltered peers */
3400 temp_converge_distance = converge_distance (target, pos, hops);
3401 if ((temp_converge_distance <= ULLONG_MAX) && (stats_total_distance + temp_converge_distance > stats_total_distance)) /* Handle largest case and overflow */
3402 stats_total_distance += temp_converge_distance;
3404 break; /* overflow case */
3405 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3406 "Choose %d matching bits (%d bits match me) (%.2f percent) converge ret %llu\n",
3407 GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey,
3409 GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey,
3412 (temp_converge_distance / (double) total_distance) *
3413 100, temp_converge_distance);
3419 /* Now handle all the further away peers */
3420 for (bc = closest_bucket + 1; bc < MAX_BUCKETS; bc++)
3422 pos = k_buckets[bc].head;
3424 while ((pos != NULL) && (count < bucket_size))
3427 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey))
3431 continue; /* Ignore bloomfiltered peers */
3433 temp_converge_distance = converge_distance (target, pos, hops);
3434 if ((temp_converge_distance <= ULLONG_MAX) && (stats_total_distance + temp_converge_distance > stats_total_distance)) /* Handle largest case and overflow */
3435 stats_total_distance += temp_converge_distance;
3437 break; /* overflow case */
3438 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3439 "Choose %d matching bits (%d bits match me) (%.2f percent) converge ret %llu\n",
3440 GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey,
3442 GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey,
3445 (temp_converge_distance / (double) total_distance) *
3446 100, temp_converge_distance);
3451 /* END PRINT STATS */
3454 /* Now actually choose a peer */
3456 GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK, total_distance);
3458 /* Go over closest sorted peers. */
3459 for (i = 0; i < offset; i++)
3462 GNUNET_CONTAINER_bloomfilter_test (bloom,
3463 &sorted_closest[i]->id.
3465 break; /* Ignore bloomfiltered peers */
3466 temp_converge_distance =
3467 converge_distance (target, sorted_closest[i], hops);
3468 if (temp_converge_distance >= selected)
3469 return sorted_closest[i];
3471 selected -= temp_converge_distance;
3474 /* Now handle peers in lower buckets (matches same # of bits as target) */
3475 for (bc = lowest_bucket; bc < closest_bucket; bc++)
3477 pos = k_buckets[bc].head;
3479 while ((pos != NULL) && (count < bucket_size))
3482 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey))
3486 continue; /* Ignore bloomfiltered peers */
3488 temp_converge_distance = converge_distance (target, pos, hops);
3489 if (temp_converge_distance >= selected)
3492 selected -= temp_converge_distance;
3498 /* Now handle all the further away peers */
3499 for (bc = closest_bucket + 1; bc < MAX_BUCKETS; bc++)
3501 pos = k_buckets[bc].head;
3503 while ((pos != NULL) && (count < bucket_size))
3506 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey))
3510 continue; /* Ignore bloomfiltered peers */
3512 temp_converge_distance = converge_distance (target, pos, hops);
3513 if (temp_converge_distance >= selected)
3516 selected -= temp_converge_distance;
3522 increment_stats ("# failed to select peer");
3528 * Task used to remove recent entries, either
3529 * after timeout, when full, or on shutdown.
3531 * @param cls the entry to remove
3532 * @param tc context, reason, etc.
3535 remove_recent (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
3537 struct RecentRequest *req = cls;
3538 static GNUNET_HashCode hash;
3540 GNUNET_assert (req != NULL);
3541 hash_from_uid (req->uid, &hash);
3542 GNUNET_assert (GNUNET_YES ==
3543 GNUNET_CONTAINER_multihashmap_remove (recent.hashmap, &hash,
3545 GNUNET_CONTAINER_heap_remove_node (recent.minHeap, req->heap_node);
3546 GNUNET_CONTAINER_bloomfilter_free (req->bloom);
3550 if ((tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN) && (0 == GNUNET_CONTAINER_multihashmap_size(recent.hashmap)) && (0 == GNUNET_CONTAINER_heap_get_size(recent.minHeap)))
3552 GNUNET_CONTAINER_multihashmap_destroy(recent.hashmap);
3553 GNUNET_CONTAINER_heap_destroy(recent.minHeap);
3559 * Remember this routing request so that if a reply is
3560 * received we can either forward it to the correct peer
3561 * or return the result locally.
3563 * @param msg_ctx Context of the route request
3565 * @return GNUNET_YES if this response was cached, GNUNET_NO if not
3568 cache_response (struct DHT_MessageContext *msg_ctx)
3570 struct DHTQueryRecord *record;
3571 struct DHTRouteSource *source_info;
3572 struct DHTRouteSource *pos;
3573 struct GNUNET_TIME_Absolute now;
3574 unsigned int current_size;
3576 current_size = GNUNET_CONTAINER_multihashmap_size (forward_list.hashmap);
3578 #if DELETE_WHEN_FULL
3579 while (current_size >= MAX_OUTSTANDING_FORWARDS)
3581 source_info = GNUNET_CONTAINER_heap_remove_root (forward_list.minHeap);
3582 GNUNET_assert (source_info != NULL);
3583 record = source_info->record;
3584 GNUNET_CONTAINER_DLL_remove (record->head, record->tail, source_info);
3585 if (record->head == NULL) /* No more entries in DLL */
3587 GNUNET_assert (GNUNET_YES ==
3588 GNUNET_CONTAINER_multihashmap_remove
3589 (forward_list.hashmap, &record->key, record));
3590 GNUNET_free (record);
3592 if (source_info->delete_task != GNUNET_SCHEDULER_NO_TASK)
3593 GNUNET_SCHEDULER_cancel (source_info->delete_task);
3594 if (source_info->find_peers_responded != NULL)
3595 GNUNET_CONTAINER_bloomfilter_free (source_info->find_peers_responded);
3596 GNUNET_free (source_info);
3598 GNUNET_CONTAINER_multihashmap_size (forward_list.hashmap);
3601 /** Non-local request and have too many outstanding forwards, discard! */
3602 if ((current_size >= MAX_OUTSTANDING_FORWARDS) && (msg_ctx->client == NULL))
3605 now = GNUNET_TIME_absolute_get ();
3607 GNUNET_CONTAINER_multihashmap_get (forward_list.hashmap, &msg_ctx->key);
3608 if (record != NULL) /* Already know this request! */
3614 memcmp (msg_ctx->peer, &pos->source,
3615 sizeof (struct GNUNET_PeerIdentity)))
3616 break; /* Already have this peer in reply list! */
3619 if ((pos != NULL) && (pos->client == msg_ctx->client)) /* Seen this already */
3621 GNUNET_CONTAINER_heap_update_cost (forward_list.minHeap, pos->hnode,
3628 record = GNUNET_malloc (sizeof (struct DHTQueryRecord));
3629 GNUNET_assert (GNUNET_OK ==
3630 GNUNET_CONTAINER_multihashmap_put (forward_list.hashmap,
3631 &msg_ctx->key, record,
3632 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
3633 memcpy (&record->key, &msg_ctx->key, sizeof (GNUNET_HashCode));
3636 source_info = GNUNET_malloc (sizeof (struct DHTRouteSource));
3637 source_info->record = record;
3638 source_info->delete_task =
3639 GNUNET_SCHEDULER_add_delayed (DHT_FORWARD_TIMEOUT, &remove_forward_entry,
3641 source_info->find_peers_responded =
3642 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K);
3643 memcpy (&source_info->source, msg_ctx->peer,
3644 sizeof (struct GNUNET_PeerIdentity));
3645 GNUNET_CONTAINER_DLL_insert_after (record->head, record->tail, record->tail,
3647 if (msg_ctx->client != NULL) /* For local request, set timeout so high it effectively never gets pushed out */
3649 source_info->client = msg_ctx->client;
3650 now = GNUNET_TIME_absolute_get_forever ();
3652 source_info->hnode =
3653 GNUNET_CONTAINER_heap_insert (forward_list.minHeap, source_info,
3656 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3657 "`%s:%s': Created new forward source info for %s uid %llu\n",
3658 my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key),
3659 msg_ctx->unique_id);
3666 * Main function that handles whether or not to route a message to other
3669 * @param msg the message to be routed
3670 * @param msg_ctx the context containing all pertinent information about the message
3673 route_message (const struct GNUNET_MessageHeader *msg,
3674 struct DHT_MessageContext *msg_ctx)
3677 struct PeerInfo *selected;
3678 #if DEBUG_DHT_ROUTING > 1
3679 struct PeerInfo *nearest;
3681 unsigned int target_forward_count;
3682 unsigned int forward_count;
3683 struct RecentRequest *recent_req;
3684 GNUNET_HashCode unique_hash;
3685 char *stat_forward_count;
3686 char *temp_stat_str;
3687 #if DEBUG_DHT_ROUTING
3691 if (malicious_dropper == GNUNET_YES)
3693 #if DEBUG_DHT_ROUTING
3694 if ((debug_routes_extended) && (dhtlog_handle != NULL))
3696 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE,
3697 msg_ctx->hop_count, GNUNET_SYSERR,
3698 &my_identity, &msg_ctx->key,
3699 msg_ctx->peer, NULL);
3702 if (msg_ctx->bloom != NULL)
3704 GNUNET_CONTAINER_bloomfilter_free (msg_ctx->bloom);
3705 msg_ctx->bloom = NULL;
3710 increment_stats (STAT_ROUTES);
3711 target_forward_count =
3712 get_forward_count (msg_ctx->hop_count, msg_ctx->replication);
3713 GNUNET_asprintf (&stat_forward_count, "# forward counts of %d",
3714 target_forward_count);
3715 increment_stats (stat_forward_count);
3716 GNUNET_free (stat_forward_count);
3717 if (msg_ctx->bloom == NULL)
3719 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K);
3721 if ((stop_on_closest == GNUNET_YES) && (msg_ctx->closest == GNUNET_YES)
3722 && (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DHT_PUT))
3723 target_forward_count = 0;
3726 * NOTICE: In Kademlia, a find peer request goes no further if the peer doesn't return
3727 * any closer peers (which is being checked for below). Since we are doing recursive
3728 * routing we have no choice but to stop forwarding in this case. This means that at
3729 * any given step the request may NOT be forwarded to alpha peers (because routes will
3730 * stop and the parallel route will not be aware of it). Of course, assuming that we
3731 * have fulfilled the Kademlia requirements for routing table fullness this will never
3732 * ever ever be a problem.
3734 * However, is this fair?
3736 * Since we use these requests to build our routing tables (and we build them in the
3737 * testing driver) we will ignore this restriction for FIND_PEER messages so that
3738 * routing tables still get constructed.
3740 if ((GNUNET_YES == strict_kademlia) && (msg_ctx->closest == GNUNET_YES)
3741 && (msg_ctx->hop_count > 0)
3742 && (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_DHT_FIND_PEER))
3743 target_forward_count = 0;
3746 GNUNET_CONTAINER_bloomfilter_add (msg_ctx->bloom, &my_identity.hashPubKey);
3747 hash_from_uid (msg_ctx->unique_id, &unique_hash);
3749 GNUNET_CONTAINER_multihashmap_contains (recent.hashmap, &unique_hash))
3752 GNUNET_CONTAINER_multihashmap_get (recent.hashmap, &unique_hash);
3753 GNUNET_assert (recent_req != NULL);
3755 memcmp (&recent_req->key, &msg_ctx->key, sizeof (GNUNET_HashCode)))
3756 increment_stats (STAT_DUPLICATE_UID);
3759 increment_stats (STAT_RECENT_SEEN);
3760 GNUNET_CONTAINER_bloomfilter_or2 (msg_ctx->bloom, recent_req->bloom,
3766 recent_req = GNUNET_malloc (sizeof (struct RecentRequest));
3767 recent_req->uid = msg_ctx->unique_id;
3768 memcpy (&recent_req->key, &msg_ctx->key, sizeof (GNUNET_HashCode));
3769 recent_req->remove_task =
3770 GNUNET_SCHEDULER_add_delayed (DEFAULT_RECENT_REMOVAL, &remove_recent,
3772 recent_req->heap_node =
3773 GNUNET_CONTAINER_heap_insert (recent.minHeap, recent_req,
3774 GNUNET_TIME_absolute_get ().abs_value);
3776 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K);
3777 GNUNET_CONTAINER_multihashmap_put (recent.hashmap, &unique_hash,
3779 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
3782 if (GNUNET_CONTAINER_multihashmap_size (recent.hashmap) > DHT_MAX_RECENT)
3784 recent_req = GNUNET_CONTAINER_heap_peek (recent.minHeap);
3785 GNUNET_assert (recent_req != NULL);
3786 GNUNET_SCHEDULER_cancel (recent_req->remove_task);
3787 GNUNET_SCHEDULER_add_now (&remove_recent, recent_req);
3791 for (i = 0; i < target_forward_count; i++)
3794 select_peer (&msg_ctx->key, msg_ctx->bloom, msg_ctx->hop_count);
3796 if (selected != NULL)
3799 if (GNUNET_CRYPTO_hash_matching_bits
3800 (&selected->id.hashPubKey,
3802 GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey,
3804 GNUNET_asprintf (&temp_stat_str,
3805 "# requests routed to close(r) peer hop %u",
3806 msg_ctx->hop_count);
3808 GNUNET_asprintf (&temp_stat_str,
3809 "# requests routed to less close peer hop %u",
3810 msg_ctx->hop_count);
3811 if (temp_stat_str != NULL)
3813 increment_stats (temp_stat_str);
3814 GNUNET_free (temp_stat_str);
3816 GNUNET_CONTAINER_bloomfilter_add (msg_ctx->bloom,
3817 &selected->id.hashPubKey);
3818 #if DEBUG_DHT_ROUTING > 1
3819 nearest = find_closest_peer (&msg_ctx->key);
3820 nearest_buf = GNUNET_strdup (GNUNET_i2s (&nearest->id));
3821 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3822 "`%s:%s': Forwarding request key %s uid %llu to peer %s (closest %s, bits %d, distance %u)\n",
3823 my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key),
3824 msg_ctx->unique_id, GNUNET_i2s (&selected->id),
3826 GNUNET_CRYPTO_hash_matching_bits (&nearest->id.
3829 distance (&nearest->id.hashPubKey, msg_ctx->key));
3830 GNUNET_free (nearest_buf);
3832 #if DEBUG_DHT_ROUTING
3833 if ((debug_routes_extended) && (dhtlog_handle != NULL))
3835 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id,
3836 DHTLOG_ROUTE, msg_ctx->hop_count,
3837 GNUNET_NO, &my_identity,
3838 &msg_ctx->key, msg_ctx->peer,
3842 forward_message (msg, selected, msg_ctx);
3846 if (msg_ctx->bloom != NULL)
3848 GNUNET_CONTAINER_bloomfilter_or2 (recent_req->bloom, msg_ctx->bloom,
3850 GNUNET_CONTAINER_bloomfilter_free (msg_ctx->bloom);
3851 msg_ctx->bloom = NULL;
3854 #if DEBUG_DHT_ROUTING
3855 if (forward_count == 0)
3856 ret = GNUNET_SYSERR;
3860 if ((debug_routes_extended) && (dhtlog_handle != NULL))
3862 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE,
3863 msg_ctx->hop_count, ret,
3864 &my_identity, &msg_ctx->key, msg_ctx->peer,
3873 * Main function that handles whether or not to route a message to other
3876 * @param msg the message to be routed
3877 * @param msg_ctx the context containing all pertinent information about the message
3880 demultiplex_message (const struct GNUNET_MessageHeader *msg,
3881 struct DHT_MessageContext *msg_ctx)
3883 /* FIXME: Should we use closest excluding those we won't route to (the bloomfilter problem)? */
3884 msg_ctx->closest = am_closest_peer (&msg_ctx->key, msg_ctx->bloom);
3885 switch (ntohs (msg->type))
3887 case GNUNET_MESSAGE_TYPE_DHT_GET: /* Add to hashmap of requests seen, search for data (always) */
3888 cache_response (msg_ctx);
3889 handle_dht_get (msg, msg_ctx);
3891 case GNUNET_MESSAGE_TYPE_DHT_PUT: /* Check if closest, if so insert data. */
3892 increment_stats (STAT_PUTS);
3893 handle_dht_put (msg, msg_ctx);
3895 case GNUNET_MESSAGE_TYPE_DHT_FIND_PEER: /* Check if closest and not started by us, check options, add to requests seen */
3896 increment_stats (STAT_FIND_PEER);
3897 if (((msg_ctx->hop_count > 0)
3899 memcmp (msg_ctx->peer, &my_identity,
3900 sizeof (struct GNUNET_PeerIdentity))))
3901 || (msg_ctx->client != NULL))
3903 cache_response (msg_ctx);
3904 if ((msg_ctx->closest == GNUNET_YES)
3905 || (msg_ctx->msg_options ==
3906 GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE))
3907 handle_dht_find_peer (msg, msg_ctx);
3910 route_message (msg, msg_ctx);
3911 #if DEBUG_DHT_ROUTING
3912 if (msg_ctx->hop_count == 0) /* Locally initiated request */
3914 if ((debug_routes) && (dhtlog_handle != NULL))
3916 dhtlog_handle->insert_dhtkey (NULL, &msg_ctx->key);
3917 dhtlog_handle->insert_query (NULL, msg_ctx->unique_id,
3919 msg_ctx->hop_count, GNUNET_NO,
3920 &my_identity, &msg_ctx->key);
3926 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
3927 "`%s': Message type (%d) not handled, forwarding anyway!\n",
3928 "DHT", ntohs (msg->type));
3929 route_message (msg, msg_ctx);
3937 * Iterator for local get request results,
3939 * @param cls closure for iterator, NULL
3940 * @param exp when does this value expire?
3941 * @param key the key this data is stored under
3942 * @param size the size of the data identified by key
3943 * @param data the actual data
3944 * @param type the type of the data
3946 * @return GNUNET_OK to continue iteration, anything else
3947 * to stop iteration.
3950 republish_content_iterator (void *cls,
3951 struct GNUNET_TIME_Absolute exp,
3952 const GNUNET_HashCode * key,
3953 size_t size, const char *data, uint32_t type)
3956 struct DHT_MessageContext *new_msg_ctx;
3957 struct GNUNET_DHT_PutMessage *put_msg;
3959 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
3960 "`%s:%s': Received `%s' response from datacache\n", my_short_id,
3963 new_msg_ctx = GNUNET_malloc (sizeof (struct DHT_MessageContext));
3965 put_msg = GNUNET_malloc (sizeof (struct GNUNET_DHT_PutMessage) + size);
3966 put_msg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_PUT);
3967 put_msg->header.size = htons (sizeof (struct GNUNET_DHT_PutMessage) + size);
3968 put_msg->expiration = GNUNET_TIME_absolute_hton (exp);
3969 put_msg->type = htons (type);
3970 memcpy (&put_msg[1], data, size);
3971 new_msg_ctx->unique_id =
3972 GNUNET_ntohll (GNUNET_CRYPTO_random_u64
3973 (GNUNET_CRYPTO_QUALITY_WEAK, (uint64_t) - 1));
3974 new_msg_ctx->replication = ntohl (DEFAULT_PUT_REPLICATION);
3975 new_msg_ctx->msg_options = ntohl (0);
3976 new_msg_ctx->network_size = estimate_diameter ();
3977 new_msg_ctx->peer = &my_identity;
3978 new_msg_ctx->bloom =
3979 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K);
3980 new_msg_ctx->hop_count = 0;
3981 new_msg_ctx->importance = DHT_DEFAULT_P2P_IMPORTANCE;
3982 new_msg_ctx->timeout = DHT_DEFAULT_P2P_TIMEOUT;
3983 increment_stats (STAT_PUT_START);
3984 demultiplex_message (&put_msg->header, new_msg_ctx);
3986 GNUNET_free (new_msg_ctx);
3987 GNUNET_free (put_msg);
3992 * Task used to republish data.
3994 * @param cls closure (a struct RepublishContext)
3995 * @param tc runtime context for this task
3998 republish_content (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
4000 struct RepublishContext *put_context = cls;
4002 unsigned int results;
4004 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
4006 GNUNET_free (put_context);
4010 GNUNET_assert (datacache != NULL); /* If we have no datacache we never should have scheduled this! */
4012 GNUNET_DATACACHE_get (datacache, &put_context->key, put_context->type,
4013 &republish_content_iterator, NULL);
4014 if (results == 0) /* Data must have expired */
4015 GNUNET_free (put_context);
4016 else /* Reschedule task for next time period */
4017 GNUNET_SCHEDULER_add_delayed (dht_republish_frequency, &republish_content,
4024 * Iterator over hash map entries.
4026 * @param cls client to search for in source routes
4027 * @param key current key code (ignored)
4028 * @param value value in the hash map, a DHTQueryRecord
4029 * @return GNUNET_YES if we should continue to
4034 find_client_records (void *cls, const GNUNET_HashCode * key, void *value)
4036 struct ClientList *client = cls;
4037 struct DHTQueryRecord *record = value;
4038 struct DHTRouteSource *pos;
4042 if (pos->client == client)
4048 GNUNET_CONTAINER_DLL_remove (record->head, record->tail, pos);
4049 GNUNET_CONTAINER_heap_remove_node (forward_list.minHeap, pos->hnode);
4050 if (pos->delete_task != GNUNET_SCHEDULER_NO_TASK)
4051 GNUNET_SCHEDULER_cancel (pos->delete_task);
4053 if (pos->find_peers_responded != NULL)
4054 GNUNET_CONTAINER_bloomfilter_free (pos->find_peers_responded);
4057 if (record->head == NULL) /* No more entries in DLL */
4059 GNUNET_assert (GNUNET_YES ==
4060 GNUNET_CONTAINER_multihashmap_remove
4061 (forward_list.hashmap, &record->key, record));
4062 GNUNET_free (record);
4068 * Functions with this signature are called whenever a client
4069 * is disconnected on the network level.
4071 * @param cls closure (NULL for dht)
4072 * @param client identification of the client; NULL
4073 * for the last call when the server is destroyed
4076 handle_client_disconnect (void *cls, struct GNUNET_SERVER_Client *client)
4078 struct ClientList *pos = client_list;
4079 struct ClientList *prev;
4080 struct ClientList *found;
4081 struct PendingMessage *reply;
4087 if (pos->client_handle == client)
4090 prev->next = pos->next;
4092 client_list = pos->next;
4102 if (found->transmit_handle != NULL)
4103 GNUNET_CONNECTION_notify_transmit_ready_cancel
4104 (found->transmit_handle);
4106 while (NULL != (reply = found->pending_head))
4108 GNUNET_CONTAINER_DLL_remove (found->pending_head,
4109 found->pending_tail, reply);
4110 GNUNET_free (reply);
4112 GNUNET_CONTAINER_multihashmap_iterate (forward_list.hashmap,
4113 &find_client_records, found);
4114 GNUNET_free (found);
4119 * Find a client if it exists, add it otherwise.
4121 * @param client the server handle to the client
4123 * @return the client if found, a new client otherwise
4125 static struct ClientList *
4126 find_active_client (struct GNUNET_SERVER_Client *client)
4128 struct ClientList *pos = client_list;
4129 struct ClientList *ret;
4133 if (pos->client_handle == client)
4138 ret = GNUNET_malloc (sizeof (struct ClientList));
4139 ret->client_handle = client;
4140 ret->next = client_list;
4148 * Task to send a malicious put message across the network.
4150 * @param cls closure for this task
4151 * @param tc the context under which the task is running
4154 malicious_put_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
4156 static struct GNUNET_DHT_PutMessage put_message;
4157 static struct DHT_MessageContext msg_ctx;
4158 static GNUNET_HashCode key;
4159 uint32_t random_key;
4161 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
4163 put_message.header.size = htons (sizeof (struct GNUNET_DHT_PutMessage));
4164 put_message.header.type = htons (GNUNET_MESSAGE_TYPE_DHT_PUT);
4165 put_message.type = htonl (GNUNET_BLOCK_DHT_MALICIOUS_MESSAGE_TYPE);
4166 put_message.expiration =
4167 GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get_forever ());
4168 memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext));
4170 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) - 1);
4171 GNUNET_CRYPTO_hash (&random_key, sizeof (uint32_t), &key);
4172 memcpy (&msg_ctx.key, &key, sizeof (GNUNET_HashCode));
4174 GNUNET_ntohll (GNUNET_CRYPTO_random_u64
4175 (GNUNET_CRYPTO_QUALITY_WEAK, (uint64_t) - 1));
4176 msg_ctx.replication = ntohl (DHT_DEFAULT_FIND_PEER_REPLICATION);
4177 msg_ctx.msg_options = ntohl (0);
4178 msg_ctx.network_size = estimate_diameter ();
4179 msg_ctx.peer = &my_identity;
4180 msg_ctx.importance = DHT_DEFAULT_P2P_IMPORTANCE;
4181 msg_ctx.timeout = DHT_DEFAULT_P2P_TIMEOUT;
4182 #if DEBUG_DHT_ROUTING
4183 if (dhtlog_handle != NULL)
4184 dhtlog_handle->insert_dhtkey (NULL, &key);
4186 increment_stats (STAT_PUT_START);
4187 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4188 "%s:%s Sending malicious PUT message with hash %s\n",
4189 my_short_id, "DHT", GNUNET_h2s (&key));
4190 demultiplex_message (&put_message.header, &msg_ctx);
4191 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_relative_multiply
4192 (GNUNET_TIME_UNIT_MILLISECONDS,
4193 malicious_put_frequency),
4194 &malicious_put_task, NULL);
4199 * Task to send a malicious put message across the network.
4201 * @param cls closure for this task
4202 * @param tc the context under which the task is running
4205 malicious_get_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
4207 static struct GNUNET_DHT_GetMessage get_message;
4208 struct DHT_MessageContext msg_ctx;
4209 static GNUNET_HashCode key;
4210 uint32_t random_key;
4212 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
4215 get_message.header.size = htons (sizeof (struct GNUNET_DHT_GetMessage));
4216 get_message.header.type = htons (GNUNET_MESSAGE_TYPE_DHT_GET);
4217 get_message.type = htonl (GNUNET_BLOCK_DHT_MALICIOUS_MESSAGE_TYPE);
4218 memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext));
4220 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, (uint32_t) - 1);
4221 GNUNET_CRYPTO_hash (&random_key, sizeof (uint32_t), &key);
4222 memcpy (&msg_ctx.key, &key, sizeof (GNUNET_HashCode));
4224 GNUNET_ntohll (GNUNET_CRYPTO_random_u64
4225 (GNUNET_CRYPTO_QUALITY_WEAK, (uint64_t) - 1));
4226 msg_ctx.replication = ntohl (DHT_DEFAULT_FIND_PEER_REPLICATION);
4227 msg_ctx.msg_options = ntohl (0);
4228 msg_ctx.network_size = estimate_diameter ();
4229 msg_ctx.peer = &my_identity;
4230 msg_ctx.importance = DHT_DEFAULT_P2P_IMPORTANCE;
4231 msg_ctx.timeout = DHT_DEFAULT_P2P_TIMEOUT;
4232 #if DEBUG_DHT_ROUTING
4233 if (dhtlog_handle != NULL)
4234 dhtlog_handle->insert_dhtkey (NULL, &key);
4236 increment_stats (STAT_GET_START);
4237 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4238 "%s:%s Sending malicious GET message with hash %s\n",
4239 my_short_id, "DHT", GNUNET_h2s (&key));
4240 demultiplex_message (&get_message.header, &msg_ctx);
4241 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_relative_multiply
4242 (GNUNET_TIME_UNIT_MILLISECONDS,
4243 malicious_get_frequency),
4244 &malicious_get_task, NULL);
4250 * Iterator over hash map entries.
4252 * @param cls closure
4253 * @param key current key code
4254 * @param value value in the hash map
4255 * @return GNUNET_YES if we should continue to
4260 add_known_to_bloom (void *cls, const GNUNET_HashCode * key, void *value)
4262 struct GNUNET_CONTAINER_BloomFilter *bloom = cls;
4263 GNUNET_CONTAINER_bloomfilter_add (bloom, key);
4268 * Task to send a find peer message for our own peer identifier
4269 * so that we can find the closest peers in the network to ourselves
4270 * and attempt to connect to them.
4272 * @param cls closure for this task
4273 * @param tc the context under which the task is running
4276 send_find_peer_message (void *cls,
4277 const struct GNUNET_SCHEDULER_TaskContext *tc)
4279 struct GNUNET_DHT_FindPeerMessage *find_peer_msg;
4280 struct DHT_MessageContext msg_ctx;
4281 struct GNUNET_TIME_Relative next_send_time;
4282 struct GNUNET_CONTAINER_BloomFilter *temp_bloom;
4284 struct GNUNET_TIME_Relative time_diff;
4285 struct GNUNET_TIME_Absolute end;
4287 double count_per_interval;
4289 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
4292 if ((newly_found_peers > bucket_size) && (GNUNET_YES == do_find_peer)) /* If we are finding peers already, no need to send out our request right now! */
4294 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
4295 "Have %d newly found peers since last find peer message sent!\n",
4297 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES,
4298 &send_find_peer_message, NULL);
4299 newly_found_peers = 0;
4303 increment_stats (STAT_FIND_PEER_START);
4305 end = GNUNET_TIME_absolute_get ();
4307 GNUNET_TIME_absolute_get_difference (find_peer_context.start, end);
4309 if (time_diff.abs_value > FIND_PEER_CALC_INTERVAL.abs_value)
4311 multiplier = time_diff.abs_value / FIND_PEER_CALC_INTERVAL.abs_value;
4312 count_per_interval = find_peer_context.count / multiplier;
4316 multiplier = FIND_PEER_CALC_INTERVAL.abs_value / time_diff.abs_value;
4317 count_per_interval = find_peer_context.count * multiplier;
4321 #if FIND_PEER_WITH_HELLO
4323 GNUNET_malloc (sizeof (struct GNUNET_DHT_FindPeerMessage) +
4324 GNUNET_HELLO_size ((struct GNUNET_HELLO_Message *)
4326 find_peer_msg->header.size =
4327 htons (sizeof (struct GNUNET_DHT_FindPeerMessage) +
4328 GNUNET_HELLO_size ((struct GNUNET_HELLO_Message *) my_hello));
4329 memcpy (&find_peer_msg[1], my_hello,
4330 GNUNET_HELLO_size ((struct GNUNET_HELLO_Message *) my_hello));
4332 find_peer_msg = GNUNET_malloc (sizeof (struct GNUNET_DHT_FindPeerMessage));
4333 find_peer_msg->header.size =
4334 htons (sizeof (struct GNUNET_DHT_FindPeerMessage));
4336 find_peer_msg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_FIND_PEER);
4338 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K);
4339 GNUNET_CONTAINER_multihashmap_iterate (all_known_peers, &add_known_to_bloom,
4341 GNUNET_assert (GNUNET_OK ==
4342 GNUNET_CONTAINER_bloomfilter_get_raw_data (temp_bloom,
4346 GNUNET_CONTAINER_bloomfilter_free (temp_bloom);
4347 memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext));
4348 memcpy (&msg_ctx.key, &my_identity.hashPubKey, sizeof (GNUNET_HashCode));
4350 GNUNET_ntohll (GNUNET_CRYPTO_random_u64
4351 (GNUNET_CRYPTO_QUALITY_STRONG, (uint64_t) - 1));
4352 msg_ctx.replication = DHT_DEFAULT_FIND_PEER_REPLICATION;
4353 msg_ctx.msg_options = DHT_DEFAULT_FIND_PEER_OPTIONS;
4354 msg_ctx.network_size = estimate_diameter ();
4355 msg_ctx.peer = &my_identity;
4356 msg_ctx.importance = DHT_DEFAULT_FIND_PEER_IMPORTANCE;
4357 msg_ctx.timeout = DHT_DEFAULT_FIND_PEER_TIMEOUT;
4359 demultiplex_message (&find_peer_msg->header, &msg_ctx);
4360 GNUNET_free (find_peer_msg);
4361 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4362 "`%s:%s': Sent `%s' request to some (?) peers\n", my_short_id,
4363 "DHT", "FIND PEER");
4364 if (newly_found_peers < bucket_size)
4366 next_send_time.rel_value =
4367 (DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value / 2) +
4368 GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_STRONG,
4369 DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value /
4374 next_send_time.rel_value = DHT_MINIMUM_FIND_PEER_INTERVAL.rel_value +
4375 GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_STRONG,
4376 DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value -
4377 DHT_MINIMUM_FIND_PEER_INTERVAL.rel_value);
4380 GNUNET_assert (next_send_time.rel_value != 0);
4381 find_peer_context.count = 0;
4382 newly_found_peers = 0;
4383 find_peer_context.start = GNUNET_TIME_absolute_get ();
4384 if (GNUNET_YES == do_find_peer)
4386 GNUNET_SCHEDULER_add_delayed (next_send_time,
4387 &send_find_peer_message, NULL);
4392 * Handler for any generic DHT messages, calls the appropriate handler
4393 * depending on message type, sends confirmation if responses aren't otherwise
4396 * @param cls closure for the service
4397 * @param client the client we received this message from
4398 * @param message the actual message received
4401 handle_dht_local_route_request (void *cls,
4402 struct GNUNET_SERVER_Client *client,
4403 const struct GNUNET_MessageHeader *message)
4405 const struct GNUNET_DHT_RouteMessage *dht_msg =
4406 (const struct GNUNET_DHT_RouteMessage *) message;
4407 const struct GNUNET_MessageHeader *enc_msg;
4408 struct DHT_MessageContext msg_ctx;
4410 enc_msg = (const struct GNUNET_MessageHeader *) &dht_msg[1];
4412 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4413 "`%s:%s': Received `%s' request from client, message type %d, key %s, uid %llu\n",
4417 ntohs (message->type),
4418 GNUNET_h2s (&dht_msg->key), GNUNET_ntohll (dht_msg->unique_id));
4420 #if DEBUG_DHT_ROUTING
4421 if (dhtlog_handle != NULL)
4422 dhtlog_handle->insert_dhtkey (NULL, &dht_msg->key);
4425 memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext));
4426 msg_ctx.client = find_active_client (client);
4427 memcpy (&msg_ctx.key, &dht_msg->key, sizeof (GNUNET_HashCode));
4428 msg_ctx.unique_id = GNUNET_ntohll (dht_msg->unique_id);
4429 msg_ctx.replication = ntohl (dht_msg->desired_replication_level);
4430 msg_ctx.msg_options = ntohl (dht_msg->options);
4431 msg_ctx.network_size = estimate_diameter ();
4432 msg_ctx.peer = &my_identity;
4433 msg_ctx.importance = DHT_DEFAULT_P2P_IMPORTANCE + 4; /* Make local routing a higher priority */
4434 msg_ctx.timeout = DHT_DEFAULT_P2P_TIMEOUT;
4436 if (ntohs (enc_msg->type) == GNUNET_MESSAGE_TYPE_DHT_GET)
4437 increment_stats (STAT_GET_START);
4438 else if (ntohs (enc_msg->type) == GNUNET_MESSAGE_TYPE_DHT_PUT)
4439 increment_stats (STAT_PUT_START);
4440 else if (ntohs (enc_msg->type) == GNUNET_MESSAGE_TYPE_DHT_FIND_PEER)
4441 increment_stats (STAT_FIND_PEER_START);
4443 if (GNUNET_YES == malicious_dropper)
4445 if (ntohs (enc_msg->type) == GNUNET_MESSAGE_TYPE_DHT_GET)
4447 #if DEBUG_DHT_ROUTING
4448 if ((debug_routes) && (dhtlog_handle != NULL))
4450 dhtlog_handle->insert_query (NULL, msg_ctx.unique_id,
4451 DHTLOG_GET, msg_ctx.hop_count,
4452 GNUNET_NO, &my_identity,
4457 else if (ntohs (enc_msg->type) == GNUNET_MESSAGE_TYPE_DHT_PUT)
4459 #if DEBUG_DHT_ROUTING
4460 if ((debug_routes) && (dhtlog_handle != NULL))
4462 dhtlog_handle->insert_query (NULL, msg_ctx.unique_id,
4463 DHTLOG_PUT, msg_ctx.hop_count,
4464 GNUNET_NO, &my_identity,
4469 GNUNET_SERVER_receive_done (client, GNUNET_OK);
4473 demultiplex_message (enc_msg, &msg_ctx);
4474 GNUNET_SERVER_receive_done (client, GNUNET_OK);
4479 * Handler for any locally received DHT control messages,
4480 * sets malicious flags mostly for now.
4482 * @param cls closure for the service
4483 * @param client the client we received this message from
4484 * @param message the actual message received
4488 handle_dht_control_message (void *cls, struct GNUNET_SERVER_Client *client,
4489 const struct GNUNET_MessageHeader *message)
4491 const struct GNUNET_DHT_ControlMessage *dht_control_msg =
4492 (const struct GNUNET_DHT_ControlMessage *) message;
4494 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4495 "`%s:%s': Received `%s' request from client, command %d\n",
4496 my_short_id, "DHT", "CONTROL",
4497 ntohs (dht_control_msg->command));
4500 switch (ntohs (dht_control_msg->command))
4502 case GNUNET_MESSAGE_TYPE_DHT_FIND_PEER:
4503 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4504 "Sending self seeking find peer request!\n");
4505 GNUNET_SCHEDULER_add_now (&send_find_peer_message, NULL);
4508 case GNUNET_MESSAGE_TYPE_DHT_MALICIOUS_GET:
4509 if (ntohs (dht_control_msg->variable) > 0)
4510 malicious_get_frequency = ntohs (dht_control_msg->variable);
4511 if (malicious_get_frequency == 0)
4512 malicious_get_frequency = DEFAULT_MALICIOUS_GET_FREQUENCY;
4513 if (malicious_getter != GNUNET_YES)
4514 GNUNET_SCHEDULER_add_now (&malicious_get_task, NULL);
4515 malicious_getter = GNUNET_YES;
4516 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4517 "%s:%s Initiating malicious GET behavior, frequency %d\n",
4518 my_short_id, "DHT", malicious_get_frequency);
4520 case GNUNET_MESSAGE_TYPE_DHT_MALICIOUS_PUT:
4521 if (ntohs (dht_control_msg->variable) > 0)
4522 malicious_put_frequency = ntohs (dht_control_msg->variable);
4523 if (malicious_put_frequency == 0)
4524 malicious_put_frequency = DEFAULT_MALICIOUS_PUT_FREQUENCY;
4525 if (malicious_putter != GNUNET_YES)
4526 GNUNET_SCHEDULER_add_now (&malicious_put_task, NULL);
4527 malicious_putter = GNUNET_YES;
4528 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4529 "%s:%s Initiating malicious PUT behavior, frequency %d\n",
4530 my_short_id, "DHT", malicious_put_frequency);
4532 case GNUNET_MESSAGE_TYPE_DHT_MALICIOUS_DROP:
4533 #if DEBUG_DHT_ROUTING
4534 if ((malicious_dropper != GNUNET_YES) && (dhtlog_handle != NULL))
4535 dhtlog_handle->set_malicious (&my_identity);
4537 malicious_dropper = GNUNET_YES;
4538 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
4539 "%s:%s Initiating malicious DROP behavior\n", my_short_id,
4544 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
4545 "%s:%s Unknown control command type `%d'!\n",
4546 my_short_id, "DHT", ntohs (dht_control_msg->command));
4550 GNUNET_SERVER_receive_done (client, GNUNET_OK);
4554 * Handler for any generic DHT stop messages, calls the appropriate handler
4555 * depending on message type (if processed locally)
4557 * @param cls closure for the service
4558 * @param client the client we received this message from
4559 * @param message the actual message received
4563 handle_dht_local_route_stop (void *cls, struct GNUNET_SERVER_Client *client,
4564 const struct GNUNET_MessageHeader *message)
4567 const struct GNUNET_DHT_StopMessage *dht_stop_msg =
4568 (const struct GNUNET_DHT_StopMessage *) message;
4569 struct DHTQueryRecord *record;
4570 struct DHTRouteSource *pos;
4572 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4573 "`%s:%s': Received `%s' request from client, uid %llu\n",
4574 my_short_id, "DHT", "GENERIC STOP",
4575 GNUNET_ntohll (dht_stop_msg->unique_id));
4578 GNUNET_CONTAINER_multihashmap_get (forward_list.hashmap,
4579 &dht_stop_msg->key);
4586 /* If the client is non-null (local request) and the client matches the requesting client, remove the entry. */
4587 if ((pos->client != NULL) && (pos->client->client_handle == client))
4589 GNUNET_SCHEDULER_cancel (pos->delete_task);
4590 pos->delete_task = GNUNET_SCHEDULER_NO_TASK;
4591 GNUNET_SCHEDULER_add_continuation (&remove_forward_entry, pos,
4592 GNUNET_SCHEDULER_REASON_PREREQ_DONE);
4598 GNUNET_SERVER_receive_done (client, GNUNET_OK);
4603 * Core handler for p2p route requests.
4606 handle_dht_p2p_route_request (void *cls,
4607 const struct GNUNET_PeerIdentity *peer,
4608 const struct GNUNET_MessageHeader *message,
4609 const struct GNUNET_TRANSPORT_ATS_Information
4613 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4614 "`%s:%s': Received P2P request from peer %s\n", my_short_id,
4615 "DHT", GNUNET_i2s (peer));
4617 struct GNUNET_DHT_P2PRouteMessage *incoming =
4618 (struct GNUNET_DHT_P2PRouteMessage *) message;
4619 struct GNUNET_MessageHeader *enc_msg =
4620 (struct GNUNET_MessageHeader *) &incoming[1];
4621 struct DHT_MessageContext *msg_ctx;
4623 if (ntohs (enc_msg->type) == GNUNET_MESSAGE_TYPE_DHT_P2P_PING) /* Throw these away. FIXME: Don't throw these away? (reply) */
4626 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4627 "%s:%s Received P2P Ping message.\n", my_short_id, "DHT");
4632 if (ntohs (enc_msg->size) >= GNUNET_SERVER_MAX_MESSAGE_SIZE - 1)
4634 GNUNET_break_op (0);
4638 if (malicious_dropper == GNUNET_YES)
4640 #if DEBUG_DHT_ROUTING
4641 if ((debug_routes_extended) && (dhtlog_handle != NULL))
4643 /** Log routes that die due to high load! */
4644 dhtlog_handle->insert_route (NULL,
4645 GNUNET_ntohll (incoming->unique_id),
4647 ntohl (incoming->hop_count),
4648 GNUNET_SYSERR, &my_identity,
4649 &incoming->key, peer, NULL);
4655 if (get_max_send_delay ().rel_value > MAX_REQUEST_TIME.rel_value)
4657 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4658 "Sending of previous replies took too long, backing off!\n");
4659 increment_stats ("# route requests dropped due to high load");
4660 decrease_max_send_delay (get_max_send_delay ());
4661 #if DEBUG_DHT_ROUTING
4662 if ((debug_routes_extended) && (dhtlog_handle != NULL))
4664 /** Log routes that die due to high load! */
4665 dhtlog_handle->insert_route (NULL,
4666 GNUNET_ntohll (incoming->unique_id),
4668 ntohl (incoming->hop_count),
4669 GNUNET_SYSERR, &my_identity,
4670 &incoming->key, peer, NULL);
4675 msg_ctx = GNUNET_malloc (sizeof (struct DHT_MessageContext));
4677 GNUNET_CONTAINER_bloomfilter_init (incoming->bloomfilter, DHT_BLOOM_SIZE,
4679 GNUNET_assert (msg_ctx->bloom != NULL);
4680 msg_ctx->hop_count = ntohl (incoming->hop_count);
4681 memcpy (&msg_ctx->key, &incoming->key, sizeof (GNUNET_HashCode));
4682 msg_ctx->replication = ntohl (incoming->desired_replication_level);
4683 msg_ctx->unique_id = GNUNET_ntohll (incoming->unique_id);
4684 msg_ctx->msg_options = ntohl (incoming->options);
4685 msg_ctx->network_size = ntohl (incoming->network_size);
4686 msg_ctx->peer = peer;
4687 msg_ctx->importance = DHT_DEFAULT_P2P_IMPORTANCE;
4688 msg_ctx->timeout = DHT_DEFAULT_P2P_TIMEOUT;
4689 demultiplex_message (enc_msg, msg_ctx);
4690 if (msg_ctx->bloom != NULL)
4692 GNUNET_CONTAINER_bloomfilter_free (msg_ctx->bloom);
4693 msg_ctx->bloom = NULL;
4695 GNUNET_free (msg_ctx);
4701 * Core handler for p2p route results.
4704 handle_dht_p2p_route_result (void *cls,
4705 const struct GNUNET_PeerIdentity *peer,
4706 const struct GNUNET_MessageHeader *message,
4707 const struct GNUNET_TRANSPORT_ATS_Information
4711 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4712 "`%s:%s': Received request from peer %s\n", my_short_id, "DHT",
4715 struct GNUNET_DHT_P2PRouteResultMessage *incoming =
4716 (struct GNUNET_DHT_P2PRouteResultMessage *) message;
4717 struct GNUNET_MessageHeader *enc_msg =
4718 (struct GNUNET_MessageHeader *) &incoming[1];
4719 struct DHT_MessageContext msg_ctx;
4721 if (ntohs (enc_msg->size) >= GNUNET_SERVER_MAX_MESSAGE_SIZE - 1)
4723 GNUNET_break_op (0);
4727 if (malicious_dropper == GNUNET_YES)
4729 #if DEBUG_DHT_ROUTING
4730 if ((debug_routes_extended) && (dhtlog_handle != NULL))
4732 /** Log routes that die due to high load! */
4733 dhtlog_handle->insert_route (NULL,
4734 GNUNET_ntohll (incoming->unique_id),
4736 ntohl (incoming->hop_count),
4737 GNUNET_SYSERR, &my_identity,
4738 &incoming->key, peer, NULL);
4744 memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext));
4745 // FIXME: call GNUNET_BLOCK_evaluate (...) -- instead of doing your own bloomfilter!
4747 GNUNET_CONTAINER_bloomfilter_init (incoming->bloomfilter, DHT_BLOOM_SIZE,
4749 GNUNET_assert (msg_ctx.bloom != NULL);
4750 memcpy (&msg_ctx.key, &incoming->key, sizeof (GNUNET_HashCode));
4751 msg_ctx.unique_id = GNUNET_ntohll (incoming->unique_id);
4752 msg_ctx.msg_options = ntohl (incoming->options);
4753 msg_ctx.hop_count = ntohl (incoming->hop_count);
4754 msg_ctx.peer = peer;
4755 msg_ctx.importance = DHT_DEFAULT_P2P_IMPORTANCE + 2; /* Make result routing a higher priority */
4756 msg_ctx.timeout = DHT_DEFAULT_P2P_TIMEOUT;
4757 route_result_message (enc_msg, &msg_ctx);
4763 * Receive the HELLO from transport service,
4764 * free current and replace if necessary.
4767 * @param message HELLO message of peer
4770 process_hello (void *cls, const struct GNUNET_MessageHeader *message)
4773 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4774 "Received our `%s' from transport service\n", "HELLO");
4777 GNUNET_assert (message != NULL);
4778 GNUNET_free_non_null (my_hello);
4779 my_hello = GNUNET_malloc (ntohs (message->size));
4780 memcpy (my_hello, message, ntohs (message->size));
4785 * Task run during shutdown.
4791 shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
4794 struct PeerInfo *pos;
4796 if (transport_handle != NULL)
4798 GNUNET_free_non_null (my_hello);
4799 GNUNET_TRANSPORT_get_hello_cancel (transport_handle, &process_hello,
4801 GNUNET_TRANSPORT_disconnect (transport_handle);
4803 for (bucket_count = lowest_bucket; bucket_count < MAX_BUCKETS;
4806 while (k_buckets[bucket_count].head != NULL)
4808 pos = k_buckets[bucket_count].head;
4810 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4811 "%s:%s Removing peer %s from bucket %d!\n", my_short_id,
4812 "DHT", GNUNET_i2s (&pos->id), bucket_count);
4814 delete_peer (pos, bucket_count);
4817 if (coreAPI != NULL)
4820 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4821 "%s:%s Disconnecting core!\n", my_short_id, "DHT");
4823 GNUNET_CORE_disconnect (coreAPI);
4826 if (datacache != NULL)
4829 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4830 "%s:%s Destroying datacache!\n", my_short_id, "DHT");
4832 GNUNET_DATACACHE_destroy (datacache);
4837 GNUNET_STATISTICS_destroy (stats, GNUNET_YES);
4840 if (dhtlog_handle != NULL)
4842 GNUNET_DHTLOG_disconnect (dhtlog_handle);
4843 dhtlog_handle = NULL;
4845 if (block_context != NULL)
4847 GNUNET_BLOCK_context_destroy (block_context);
4848 block_context = NULL;
4850 GNUNET_free_non_null (my_short_id);
4856 * To be called on core init/fail.
4858 * @param cls service closure
4859 * @param server handle to the server for this service
4860 * @param identity the public identity of this peer
4861 * @param publicKey the public key of this peer
4864 core_init (void *cls,
4865 struct GNUNET_CORE_Handle *server,
4866 const struct GNUNET_PeerIdentity *identity,
4867 const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *publicKey)
4873 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4874 "%s: Connection to core FAILED!\n", "dht",
4875 GNUNET_i2s (identity));
4877 GNUNET_SCHEDULER_cancel (cleanup_task);
4878 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
4882 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4883 "%s: Core connection initialized, I am peer: %s\n", "dht",
4884 GNUNET_i2s (identity));
4887 /* Copy our identity so we can use it */
4888 memcpy (&my_identity, identity, sizeof (struct GNUNET_PeerIdentity));
4889 if (my_short_id != NULL)
4890 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
4891 "%s Receive CORE INIT message but have already been initialized! Did CORE fail?\n",
4893 my_short_id = GNUNET_strdup (GNUNET_i2s (&my_identity));
4894 /* Set the server to local variable */
4897 if (dhtlog_handle != NULL)
4898 dhtlog_handle->insert_node (NULL, &my_identity);
4902 static struct GNUNET_SERVER_MessageHandler plugin_handlers[] = {
4903 {&handle_dht_local_route_request, NULL, GNUNET_MESSAGE_TYPE_DHT_LOCAL_ROUTE,
4905 {&handle_dht_local_route_stop, NULL,
4906 GNUNET_MESSAGE_TYPE_DHT_LOCAL_ROUTE_STOP, 0},
4907 {&handle_dht_control_message, NULL, GNUNET_MESSAGE_TYPE_DHT_CONTROL, 0},
4912 static struct GNUNET_CORE_MessageHandler core_handlers[] = {
4913 {&handle_dht_p2p_route_request, GNUNET_MESSAGE_TYPE_DHT_P2P_ROUTE, 0},
4914 {&handle_dht_p2p_route_result, GNUNET_MESSAGE_TYPE_DHT_P2P_ROUTE_RESULT, 0},
4920 * Method called whenever a peer connects.
4922 * @param cls closure
4923 * @param peer peer identity this notification is about
4924 * @param atsi performance data
4927 handle_core_connect (void *cls,
4928 const struct GNUNET_PeerIdentity *peer,
4929 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
4931 struct PeerInfo *ret;
4934 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4935 "%s:%s Receives core connect message for peer %s distance %d!\n",
4936 my_short_id, "dht", GNUNET_i2s (peer), distance);
4940 GNUNET_CONTAINER_multihashmap_contains (all_known_peers,
4943 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4944 "%s:%s Received %s message for peer %s, but already have peer in RT!",
4945 my_short_id, "DHT", "CORE CONNECT", GNUNET_i2s (peer));
4949 if (datacache != NULL)
4950 GNUNET_DATACACHE_put (datacache, &peer->hashPubKey,
4951 sizeof (struct GNUNET_PeerIdentity),
4952 (const char *) peer, GNUNET_BLOCK_TYPE_DHT_HELLO,
4953 GNUNET_TIME_absolute_get_forever ());
4954 ret = try_add_peer (peer, find_current_bucket (&peer->hashPubKey), atsi);
4957 newly_found_peers++;
4958 GNUNET_CONTAINER_multihashmap_put (all_known_peers, &peer->hashPubKey,
4960 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
4963 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4964 "%s:%s Adding peer to routing list: %s\n", my_short_id, "DHT",
4965 ret == NULL ? "NOT ADDED" : "PEER ADDED");
4971 * Method called whenever a peer disconnects.
4973 * @param cls closure
4974 * @param peer peer identity this notification is about
4977 handle_core_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer)
4979 struct PeerInfo *to_remove;
4982 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4983 "%s:%s: Received peer disconnect message for peer `%s' from %s\n",
4984 my_short_id, "DHT", GNUNET_i2s (peer), "CORE");
4987 GNUNET_CONTAINER_multihashmap_contains (all_known_peers,
4990 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4991 "%s:%s: do not have peer `%s' in RT, can't disconnect!\n",
4992 my_short_id, "DHT", GNUNET_i2s (peer));
4995 increment_stats (STAT_DISCONNECTS);
4996 GNUNET_assert (GNUNET_CONTAINER_multihashmap_contains
4997 (all_known_peers, &peer->hashPubKey));
4999 GNUNET_CONTAINER_multihashmap_get (all_known_peers, &peer->hashPubKey);
5000 GNUNET_assert (to_remove != NULL);
5002 memcmp (peer, &to_remove->id,
5003 sizeof (struct GNUNET_PeerIdentity)));
5004 current_bucket = find_current_bucket (&to_remove->id.hashPubKey);
5005 delete_peer (to_remove, current_bucket);
5010 * Process dht requests.
5012 * @param cls closure
5013 * @param server the initialized server
5014 * @param c configuration to use
5018 struct GNUNET_SERVER_Handle *server,
5019 const struct GNUNET_CONFIGURATION_Handle *c)
5021 struct GNUNET_TIME_Relative next_send_time;
5022 unsigned long long temp_config_num;
5023 char *converge_modifier_buf;
5026 datacache = GNUNET_DATACACHE_create (cfg, "dhtcache");
5027 GNUNET_SERVER_add_handlers (server, plugin_handlers);
5028 GNUNET_SERVER_disconnect_notify (server, &handle_client_disconnect, NULL);
5029 coreAPI = GNUNET_CORE_connect (cfg, /* Main configuration */
5030 DEFAULT_CORE_QUEUE_SIZE, /* queue size */
5031 NULL, /* Closure passed to DHT functions */
5032 &core_init, /* Call core_init once connected */
5033 &handle_core_connect, /* Handle connects */
5034 &handle_core_disconnect, /* remove peers on disconnects */
5035 NULL, /* Do we care about "status" updates? */
5036 NULL, /* Don't want notified about all incoming messages */
5037 GNUNET_NO, /* For header only inbound notification */
5038 NULL, /* Don't want notified about all outbound messages */
5039 GNUNET_NO, /* For header only outbound notification */
5040 core_handlers); /* Register these handlers */
5042 if (coreAPI == NULL)
5044 transport_handle = GNUNET_TRANSPORT_connect (cfg,
5045 NULL, NULL, NULL, NULL, NULL);
5046 if (transport_handle != NULL)
5047 GNUNET_TRANSPORT_get_hello (transport_handle, &process_hello, NULL);
5049 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
5050 "Failed to connect to transport service!\n");
5051 block_context = GNUNET_BLOCK_context_create (cfg);
5052 lowest_bucket = MAX_BUCKETS - 1;
5053 forward_list.hashmap =
5054 GNUNET_CONTAINER_multihashmap_create (MAX_OUTSTANDING_FORWARDS / 10);
5055 forward_list.minHeap =
5056 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
5057 all_known_peers = GNUNET_CONTAINER_multihashmap_create (MAX_BUCKETS / 8);
5058 recent_find_peer_requests =
5059 GNUNET_CONTAINER_multihashmap_create (MAX_BUCKETS / 8);
5060 GNUNET_assert (all_known_peers != NULL);
5062 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht_testing",
5065 debug_routes = GNUNET_YES;
5069 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "strict_kademlia"))
5071 strict_kademlia = GNUNET_YES;
5075 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "stop_on_closest"))
5077 stop_on_closest = GNUNET_YES;
5081 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "stop_found"))
5083 stop_on_found = GNUNET_YES;
5087 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "malicious_getter"))
5089 malicious_getter = GNUNET_YES;
5090 if (GNUNET_NO == GNUNET_CONFIGURATION_get_value_number (cfg, "DHT",
5091 "MALICIOUS_GET_FREQUENCY",
5092 &malicious_get_frequency))
5093 malicious_get_frequency = DEFAULT_MALICIOUS_GET_FREQUENCY;
5096 if (GNUNET_YES != GNUNET_CONFIGURATION_get_value_number (cfg, "DHT",
5100 max_hops = DEFAULT_MAX_HOPS;
5103 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "DHT",
5106 use_max_hops = GNUNET_YES;
5110 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "malicious_putter"))
5112 malicious_putter = GNUNET_YES;
5113 if (GNUNET_NO == GNUNET_CONFIGURATION_get_value_number (cfg, "DHT",
5114 "MALICIOUS_PUT_FREQUENCY",
5115 &malicious_put_frequency))
5116 malicious_put_frequency = DEFAULT_MALICIOUS_PUT_FREQUENCY;
5119 dht_republish_frequency = GNUNET_DHT_DEFAULT_REPUBLISH_FREQUENCY;
5121 GNUNET_CONFIGURATION_get_value_number (cfg, "DHT",
5122 "REPLICATION_FREQUENCY",
5125 dht_republish_frequency =
5126 GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES,
5131 GNUNET_CONFIGURATION_get_value_number (cfg, "DHT", "bucket_size",
5134 bucket_size = (unsigned int) temp_config_num;
5138 GNUNET_CONFIGURATION_get_value_number (cfg, "DHT", "kad_alpha",
5139 &kademlia_replication))
5141 kademlia_replication = DEFAULT_KADEMLIA_REPLICATION;
5145 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "malicious_dropper"))
5147 malicious_dropper = GNUNET_YES;
5151 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "republish"))
5152 do_republish = GNUNET_NO;
5155 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "do_find_peer"))
5157 do_find_peer = GNUNET_NO;
5160 do_find_peer = GNUNET_YES;
5163 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "use_real_distance"))
5164 use_real_distance = GNUNET_YES;
5167 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht_testing",
5168 "mysql_logging_extended"))
5170 debug_routes = GNUNET_YES;
5171 debug_routes_extended = GNUNET_YES;
5174 #if DEBUG_DHT_ROUTING
5175 if (GNUNET_YES == debug_routes)
5177 dhtlog_handle = GNUNET_DHTLOG_connect (cfg);
5178 if (dhtlog_handle == NULL)
5180 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
5181 "Could not connect to mysql logging server, logging will not happen!");
5186 converge_option = DHT_CONVERGE_SQUARE;
5188 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "converge_linear"))
5190 converge_option = DHT_CONVERGE_LINEAR;
5192 else if (GNUNET_YES ==
5193 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht",
5194 "converge_exponential"))
5196 converge_option = DHT_CONVERGE_EXPONENTIAL;
5198 else if (GNUNET_YES ==
5199 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht",
5202 converge_option = DHT_CONVERGE_RANDOM;
5204 else if (GNUNET_YES ==
5205 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht",
5208 converge_option = DHT_CONVERGE_BINARY;
5212 GNUNET_CONFIGURATION_get_value_string (cfg, "dht", "converge_modifier",
5213 &converge_modifier_buf))
5215 if (1 != sscanf (converge_modifier_buf, "%f", &converge_modifier))
5217 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
5218 "Failed to read decimal value for %s from `%s'\n",
5219 "CONVERGE_MODIFIER", converge_modifier_buf);
5220 converge_modifier = 0.0;
5222 GNUNET_free (converge_modifier_buf);
5225 stats = GNUNET_STATISTICS_create ("dht", cfg);
5229 GNUNET_STATISTICS_set (stats, STAT_ROUTES, 0, GNUNET_NO);
5230 GNUNET_STATISTICS_set (stats, STAT_ROUTE_FORWARDS, 0, GNUNET_NO);
5231 GNUNET_STATISTICS_set (stats, STAT_ROUTE_FORWARDS_CLOSEST, 0,
5233 GNUNET_STATISTICS_set (stats, STAT_RESULTS, 0, GNUNET_NO);
5234 GNUNET_STATISTICS_set (stats, STAT_RESULTS_TO_CLIENT, 0, GNUNET_NO);
5235 GNUNET_STATISTICS_set (stats, STAT_RESULT_FORWARDS, 0, GNUNET_NO);
5236 GNUNET_STATISTICS_set (stats, STAT_GETS, 0, GNUNET_NO);
5237 GNUNET_STATISTICS_set (stats, STAT_PUTS, 0, GNUNET_NO);
5238 GNUNET_STATISTICS_set (stats, STAT_PUTS_INSERTED, 0, GNUNET_NO);
5239 GNUNET_STATISTICS_set (stats, STAT_FIND_PEER, 0, GNUNET_NO);
5240 GNUNET_STATISTICS_set (stats, STAT_FIND_PEER_START, 0, GNUNET_NO);
5241 GNUNET_STATISTICS_set (stats, STAT_GET_START, 0, GNUNET_NO);
5242 GNUNET_STATISTICS_set (stats, STAT_PUT_START, 0, GNUNET_NO);
5243 GNUNET_STATISTICS_set (stats, STAT_FIND_PEER_REPLY, 0, GNUNET_NO);
5244 GNUNET_STATISTICS_set (stats, STAT_FIND_PEER_ANSWER, 0, GNUNET_NO);
5245 GNUNET_STATISTICS_set (stats, STAT_BLOOM_FIND_PEER, 0, GNUNET_NO);
5246 GNUNET_STATISTICS_set (stats, STAT_GET_REPLY, 0, GNUNET_NO);
5247 GNUNET_STATISTICS_set (stats, STAT_GET_RESPONSE_START, 0, GNUNET_NO);
5248 GNUNET_STATISTICS_set (stats, STAT_HELLOS_PROVIDED, 0, GNUNET_NO);
5249 GNUNET_STATISTICS_set (stats, STAT_DISCONNECTS, 0, GNUNET_NO);
5251 /* FIXME: if there are no recent requests then these never get freed, but alternative is _annoying_! */
5252 recent.hashmap = GNUNET_CONTAINER_multihashmap_create (DHT_MAX_RECENT / 2);
5254 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
5255 if (GNUNET_YES == do_find_peer)
5257 next_send_time.rel_value = DHT_MINIMUM_FIND_PEER_INTERVAL.rel_value +
5258 GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_STRONG,
5259 (DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value /
5261 DHT_MINIMUM_FIND_PEER_INTERVAL.rel_value);
5262 find_peer_context.start = GNUNET_TIME_absolute_get ();
5263 GNUNET_SCHEDULER_add_delayed (next_send_time,
5264 &send_find_peer_message,
5265 &find_peer_context);
5268 /* Scheduled the task to clean up when shutdown is called */
5269 cleanup_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
5270 &shutdown_task, NULL);
5274 * The main function for the dht service.
5276 * @param argc number of arguments from the command line
5277 * @param argv command line arguments
5278 * @return 0 ok, 1 on error
5281 main (int argc, char *const *argv)
5286 GNUNET_SERVICE_run (argc,
5289 GNUNET_SERVICE_OPTION_NONE, &run, NULL)) ? 0 : 1;
5290 GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (recent.hashmap));
5291 GNUNET_assert (0 == GNUNET_CONTAINER_heap_get_size (recent.minHeap));
5292 GNUNET_CONTAINER_multihashmap_destroy (recent_find_peer_requests);
5293 GNUNET_CONTAINER_multihashmap_destroy (recent.hashmap);
5294 GNUNET_CONTAINER_heap_destroy (recent.minHeap);