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_CONTAINER_DLL_remove (peer->head, peer->tail, pending);
1179 GNUNET_free (pending);
1180 pending = peer->head;
1183 if ((peer->head != NULL) && (peer->send_task == GNUNET_SCHEDULER_NO_TASK))
1184 peer->send_task = GNUNET_SCHEDULER_add_now (&try_core_send, peer);
1191 * Compute the distance between have and target as a 32-bit value.
1192 * Differences in the lower bits must count stronger than differences
1193 * in the higher bits.
1195 * @return 0 if have==target, otherwise a number
1196 * that is larger as the distance between
1197 * the two hash codes increases
1200 distance (const GNUNET_HashCode * target, const GNUNET_HashCode * have)
1202 unsigned int bucket;
1207 /* We have to represent the distance between two 2^9 (=512)-bit
1208 numbers as a 2^5 (=32)-bit number with "0" being used for the
1209 two numbers being identical; furthermore, we need to
1210 guarantee that a difference in the number of matching
1211 bits is always represented in the result.
1213 We use 2^32/2^9 numerical values to distinguish between
1214 hash codes that have the same LSB bit distance and
1215 use the highest 2^9 bits of the result to signify the
1216 number of (mis)matching LSB bits; if we have 0 matching
1217 and hence 512 mismatching LSB bits we return -1 (since
1218 512 itself cannot be represented with 9 bits) */
1220 /* first, calculate the most significant 9 bits of our
1221 result, aka the number of LSBs */
1222 bucket = GNUNET_CRYPTO_hash_matching_bits (target, have);
1223 /* bucket is now a value between 0 and 512 */
1225 return 0; /* perfect match */
1227 return (unsigned int) -1; /* LSB differs; use max (if we did the bit-shifting
1228 below, we'd end up with max+1 (overflow)) */
1230 /* calculate the most significant bits of the final result */
1231 msb = (512 - bucket) << (32 - 9);
1232 /* calculate the 32-9 least significant bits of the final result by
1233 looking at the differences in the 32-9 bits following the
1234 mismatching bit at 'bucket' */
1236 for (i = bucket + 1;
1237 (i < sizeof (GNUNET_HashCode) * 8) && (i < bucket + 1 + 32 - 9); i++)
1239 if (GNUNET_CRYPTO_hash_get_bit (target, i) !=
1240 GNUNET_CRYPTO_hash_get_bit (have, i))
1241 lsb |= (1 << (bucket + 32 - 9 - i)); /* first bit set will be 10,
1242 last bit set will be 31 -- if
1243 i does not reach 512 first... */
1249 * Return a number that is larger the closer the
1250 * "have" GNUNET_hash code is to the "target".
1252 * @return inverse distance metric, non-zero.
1253 * Must fudge the value if NO bits match.
1256 inverse_distance (const GNUNET_HashCode * target,
1257 const GNUNET_HashCode * have)
1259 if (GNUNET_CRYPTO_hash_matching_bits (target, have) == 0)
1260 return 1; /* Never return 0! */
1261 return ((unsigned int) -1) - distance (target, have);
1265 * Find the optimal bucket for this key, regardless
1266 * of the current number of buckets in use.
1268 * @param hc the hashcode to compare our identity to
1270 * @return the proper bucket index, or GNUNET_SYSERR
1271 * on error (same hashcode)
1274 find_bucket (const GNUNET_HashCode * hc)
1278 bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, hc);
1279 if (bits == MAX_BUCKETS)
1280 return GNUNET_SYSERR;
1281 return MAX_BUCKETS - bits - 1;
1285 * Find which k-bucket this peer should go into,
1286 * taking into account the size of the k-bucket
1287 * array. This means that if more bits match than
1288 * there are currently buckets, lowest_bucket will
1291 * @param hc GNUNET_HashCode we are finding the bucket for.
1293 * @return the proper bucket index for this key,
1294 * or GNUNET_SYSERR on error (same hashcode)
1297 find_current_bucket (const GNUNET_HashCode * hc)
1300 actual_bucket = find_bucket (hc);
1302 if (actual_bucket == GNUNET_SYSERR) /* hc and our peer identity match! */
1303 return lowest_bucket;
1304 else if (actual_bucket < lowest_bucket) /* actual_bucket not yet used */
1305 return lowest_bucket;
1307 return actual_bucket;
1312 * Find a routing table entry from a peer identity
1314 * @param peer the peer to look up
1316 * @return the bucket number holding the peer, GNUNET_SYSERR if not found
1319 find_bucket_by_peer (const struct PeerInfo *peer)
1322 struct PeerInfo *pos;
1324 for (bucket = lowest_bucket; bucket < MAX_BUCKETS - 1; bucket++)
1326 pos = k_buckets[bucket].head;
1335 return GNUNET_SYSERR; /* No such peer. */
1341 * Print the complete routing table for this peer.
1344 print_routing_table ()
1347 struct PeerInfo *pos;
1348 char char_buf[30000];
1350 memset (char_buf, 0, sizeof (char_buf));
1353 sprintf (&char_buf[char_pos], "Printing routing table for peer %s\n",
1355 //fprintf(stderr, "Printing routing table for peer %s\n", my_short_id);
1356 for (bucket = lowest_bucket; bucket < MAX_BUCKETS; bucket++)
1358 pos = k_buckets[bucket].head;
1359 char_pos += sprintf (&char_buf[char_pos], "Bucket %d:\n", bucket);
1360 //fprintf(stderr, "Bucket %d:\n", bucket);
1363 //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));
1365 sprintf (&char_buf[char_pos],
1366 "\tPeer %s, best bucket %d, %d bits match\n",
1367 GNUNET_i2s (&pos->id), find_bucket (&pos->id.hashPubKey),
1368 GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey,
1374 fprintf (stderr, "%s", char_buf);
1380 * Find a routing table entry from a peer identity
1382 * @param peer the peer identity to look up
1384 * @return the routing table entry, or NULL if not found
1386 static struct PeerInfo *
1387 find_peer_by_id (const struct GNUNET_PeerIdentity *peer)
1390 struct PeerInfo *pos;
1391 bucket = find_current_bucket (&peer->hashPubKey);
1393 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
1396 pos = k_buckets[bucket].head;
1399 if (0 == memcmp (&pos->id, peer, sizeof (struct GNUNET_PeerIdentity)))
1403 return NULL; /* No such peer. */
1406 /* Forward declaration */
1408 update_core_preference (void *cls,
1409 const struct GNUNET_SCHEDULER_TaskContext *tc);
1411 * Function called with statistics about the given peer.
1413 * @param cls closure
1414 * @param peer identifies the peer
1415 * @param bpm_out set to the current bandwidth limit (sending) for this peer
1416 * @param amount set to the amount that was actually reserved or unreserved;
1417 * either the full requested amount or zero (no partial reservations)
1418 * @param preference current traffic preference for the given peer
1421 update_core_preference_finish (void *cls,
1422 const struct GNUNET_PeerIdentity *peer,
1423 struct GNUNET_BANDWIDTH_Value32NBO bpm_out,
1424 int amount, uint64_t preference)
1426 struct PeerInfo *peer_info = cls;
1427 peer_info->info_ctx = NULL;
1428 GNUNET_SCHEDULER_add_delayed (DHT_DEFAULT_PREFERENCE_INTERVAL,
1429 &update_core_preference, peer_info);
1433 update_core_preference (void *cls,
1434 const struct GNUNET_SCHEDULER_TaskContext *tc)
1436 struct PeerInfo *peer = cls;
1437 uint64_t preference;
1438 unsigned int matching;
1439 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
1444 GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey,
1445 &peer->id.hashPubKey);
1448 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1449 "Peer identifier matches by %u bits, only shifting as much as we can!\n",
1453 preference = 1LL << matching;
1454 peer->info_ctx = GNUNET_CORE_peer_change_preference (coreAPI,
1456 GNUNET_TIME_relative_get_forever
1458 GNUNET_BANDWIDTH_value_init
1461 &update_core_preference_finish,
1466 * Really add a peer to a bucket (only do assertions
1469 * @param peer GNUNET_PeerIdentity of the peer to add
1470 * @param bucket the already figured out bucket to add
1472 * @param atsi performance information
1474 * @return the newly added PeerInfo
1476 static struct PeerInfo *
1477 add_peer (const struct GNUNET_PeerIdentity *peer,
1478 unsigned int bucket,
1479 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
1481 struct PeerInfo *new_peer;
1482 GNUNET_assert (bucket < MAX_BUCKETS);
1483 GNUNET_assert (peer != NULL);
1484 new_peer = GNUNET_malloc (sizeof (struct PeerInfo));
1486 new_peer->latency = latency;
1487 new_peer->distance = distance;
1490 memcpy (&new_peer->id, peer, sizeof (struct GNUNET_PeerIdentity));
1492 GNUNET_CONTAINER_DLL_insert_after (k_buckets[bucket].head,
1493 k_buckets[bucket].tail,
1494 k_buckets[bucket].tail, new_peer);
1495 k_buckets[bucket].peers_size++;
1497 if ((GNUNET_CRYPTO_hash_matching_bits
1498 (&my_identity.hashPubKey, &peer->hashPubKey) > 0)
1499 && (k_buckets[bucket].peers_size <= bucket_size))
1501 #if DO_UPDATE_PREFERENCE
1502 new_peer->preference_task =
1503 GNUNET_SCHEDULER_add_now (&update_core_preference, new_peer);
1511 * Given a peer and its corresponding bucket,
1512 * remove it from that bucket. Does not free
1513 * the PeerInfo struct, nor cancel messages
1514 * or free messages waiting to be sent to this
1517 * @param peer the peer to remove
1518 * @param bucket the bucket the peer belongs to
1521 remove_peer (struct PeerInfo *peer, unsigned int bucket)
1523 GNUNET_assert (k_buckets[bucket].peers_size > 0);
1524 GNUNET_CONTAINER_DLL_remove (k_buckets[bucket].head,
1525 k_buckets[bucket].tail, peer);
1526 k_buckets[bucket].peers_size--;
1528 if ((bucket == lowest_bucket) && (k_buckets[lowest_bucket].peers_size == 0)
1529 && (lowest_bucket < MAX_BUCKETS - 1))
1535 * Removes peer from a bucket, then frees associated
1536 * resources and frees peer.
1538 * @param peer peer to be removed and freed
1539 * @param bucket which bucket this peer belongs to
1542 delete_peer (struct PeerInfo *peer, unsigned int bucket)
1544 struct P2PPendingMessage *pos;
1545 struct P2PPendingMessage *next;
1547 struct PeerInfo *peer_pos;
1549 peer_pos = k_buckets[bucket].head;
1550 while ((peer_pos != NULL) && (peer_pos != peer))
1551 peer_pos = peer_pos->next;
1552 if (peer_pos == NULL)
1554 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1555 "%s:%s: Expected peer `%s' in bucket %d\n", my_short_id,
1556 "DHT", GNUNET_i2s (&peer->id), bucket);
1557 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1558 "%s:%s: Lowest bucket: %d, find_current_bucket: %d, peer resides in bucket: %d\n",
1559 my_short_id, "DHT", lowest_bucket,
1560 find_current_bucket (&peer->id.hashPubKey),
1561 find_bucket_by_peer (peer));
1563 GNUNET_assert (peer_pos != NULL);
1565 remove_peer (peer, bucket); /* First remove the peer from its bucket */
1567 if (peer->send_task != GNUNET_SCHEDULER_NO_TASK)
1568 GNUNET_SCHEDULER_cancel (peer->send_task);
1569 if ((peer->th != NULL) && (coreAPI != NULL))
1570 GNUNET_CORE_notify_transmit_ready_cancel (peer->th);
1573 while (pos != NULL) /* Remove any pending messages for this peer */
1576 ("# dht pending messages discarded (due to disconnect/shutdown)");
1582 GNUNET_assert (GNUNET_CONTAINER_multihashmap_contains
1583 (all_known_peers, &peer->id.hashPubKey));
1584 GNUNET_assert (GNUNET_YES ==
1585 GNUNET_CONTAINER_multihashmap_remove (all_known_peers,
1586 &peer->id.hashPubKey,
1593 * Iterator over hash map entries.
1595 * @param cls closure
1596 * @param key current key code
1597 * @param value PeerInfo of the peer to move to new lowest bucket
1598 * @return GNUNET_YES if we should continue to
1603 move_lowest_bucket (void *cls, const GNUNET_HashCode * key, void *value)
1605 struct PeerInfo *peer = value;
1608 GNUNET_assert (lowest_bucket > 0);
1609 new_bucket = lowest_bucket - 1;
1610 remove_peer (peer, lowest_bucket);
1611 GNUNET_CONTAINER_DLL_insert_after (k_buckets[new_bucket].head,
1612 k_buckets[new_bucket].tail,
1613 k_buckets[new_bucket].tail, peer);
1614 k_buckets[new_bucket].peers_size++;
1620 * The current lowest bucket is full, so change the lowest
1621 * bucket to the next lower down, and move any appropriate
1622 * entries in the current lowest bucket to the new bucket.
1625 enable_next_bucket ()
1627 struct GNUNET_CONTAINER_MultiHashMap *to_remove;
1628 struct PeerInfo *pos;
1629 GNUNET_assert (lowest_bucket > 0);
1630 to_remove = GNUNET_CONTAINER_multihashmap_create (bucket_size);
1631 pos = k_buckets[lowest_bucket].head;
1634 fprintf (stderr, "Printing RT before new bucket\n");
1635 print_routing_table ();
1637 /* Populate the array of peers which should be in the next lowest bucket */
1640 if (find_bucket (&pos->id.hashPubKey) < lowest_bucket)
1641 GNUNET_CONTAINER_multihashmap_put (to_remove, &pos->id.hashPubKey,
1643 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
1647 /* Remove peers from lowest bucket, insert into next lowest bucket */
1648 GNUNET_CONTAINER_multihashmap_iterate (to_remove, &move_lowest_bucket,
1650 GNUNET_CONTAINER_multihashmap_destroy (to_remove);
1651 lowest_bucket = lowest_bucket - 1;
1653 fprintf (stderr, "Printing RT after new bucket\n");
1654 print_routing_table ();
1659 * Find the closest peer in our routing table to the
1662 * @return The closest peer in our routing table to the
1663 * key, or NULL on error.
1665 static struct PeerInfo *
1666 find_closest_peer (const GNUNET_HashCode * hc)
1668 struct PeerInfo *pos;
1669 struct PeerInfo *current_closest;
1670 unsigned int lowest_distance;
1671 unsigned int temp_distance;
1675 lowest_distance = -1;
1677 if (k_buckets[lowest_bucket].peers_size == 0)
1680 current_closest = NULL;
1681 for (bucket = lowest_bucket; bucket < MAX_BUCKETS; bucket++)
1683 pos = k_buckets[bucket].head;
1685 while ((pos != NULL) && (count < bucket_size))
1687 temp_distance = distance (&pos->id.hashPubKey, hc);
1688 if (temp_distance <= lowest_distance)
1690 lowest_distance = temp_distance;
1691 current_closest = pos;
1697 GNUNET_assert (current_closest != NULL);
1698 return current_closest;
1703 * Function called to send a request out to another peer.
1704 * Called both for locally initiated requests and those
1705 * received from other peers.
1707 * @param msg the encapsulated message
1708 * @param peer the peer to forward the message to
1709 * @param msg_ctx the context of the message (hop count, bloom, etc.)
1712 forward_message (const struct GNUNET_MessageHeader *msg,
1713 struct PeerInfo *peer, struct DHT_MessageContext *msg_ctx)
1715 struct GNUNET_DHT_P2PRouteMessage *route_message;
1716 struct P2PPendingMessage *pending;
1720 increment_stats (STAT_ROUTE_FORWARDS);
1721 GNUNET_assert (peer != NULL);
1722 if ((msg_ctx->closest != GNUNET_YES)
1723 && (peer == find_closest_peer (&msg_ctx->key)))
1724 increment_stats (STAT_ROUTE_FORWARDS_CLOSEST);
1726 msize = sizeof (struct GNUNET_DHT_P2PRouteMessage) + ntohs (msg->size);
1727 GNUNET_assert (msize <= GNUNET_SERVER_MAX_MESSAGE_SIZE);
1728 psize = sizeof (struct P2PPendingMessage) + msize;
1729 pending = GNUNET_malloc (psize);
1730 pending->msg = (struct GNUNET_MessageHeader *) &pending[1];
1731 pending->importance = msg_ctx->importance;
1732 pending->timeout = msg_ctx->timeout;
1733 route_message = (struct GNUNET_DHT_P2PRouteMessage *) pending->msg;
1734 route_message->header.size = htons (msize);
1735 route_message->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_ROUTE);
1736 route_message->options = htonl (msg_ctx->msg_options);
1737 route_message->hop_count = htonl (msg_ctx->hop_count + 1);
1738 route_message->network_size = htonl (msg_ctx->network_size);
1739 route_message->desired_replication_level = htonl (msg_ctx->replication);
1740 route_message->unique_id = GNUNET_htonll (msg_ctx->unique_id);
1741 if (msg_ctx->bloom != NULL)
1742 GNUNET_assert (GNUNET_OK ==
1743 GNUNET_CONTAINER_bloomfilter_get_raw_data (msg_ctx->bloom,
1747 memcpy (&route_message->key, &msg_ctx->key, sizeof (GNUNET_HashCode));
1748 memcpy (&route_message[1], msg, ntohs (msg->size));
1750 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1751 "%s:%s Adding pending message size %d for peer %s\n",
1752 my_short_id, "DHT", msize, GNUNET_i2s (&peer->id));
1754 peer->pending_count++;
1755 increment_stats ("# pending messages scheduled");
1756 GNUNET_CONTAINER_DLL_insert_after (peer->head, peer->tail, peer->tail,
1758 if (peer->send_task == GNUNET_SCHEDULER_NO_TASK)
1759 peer->send_task = GNUNET_SCHEDULER_add_now (&try_core_send, peer);
1764 * Task used to send ping messages to peers so that
1765 * they don't get disconnected.
1767 * @param cls the peer to send a ping message to
1768 * @param tc context, reason, etc.
1771 periodic_ping_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1773 struct PeerInfo *peer = cls;
1774 struct GNUNET_MessageHeader ping_message;
1775 struct DHT_MessageContext msg_ctx;
1777 if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
1780 ping_message.size = htons (sizeof (struct GNUNET_MessageHeader));
1781 ping_message.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_PING);
1783 memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext));
1785 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1786 "%s:%s Sending periodic ping to %s\n", my_short_id, "DHT",
1787 GNUNET_i2s (&peer->id));
1789 forward_message (&ping_message, peer, &msg_ctx);
1791 GNUNET_SCHEDULER_add_delayed (DHT_DEFAULT_PING_DELAY, &periodic_ping_task,
1796 * Schedule PING messages for the top X peers in each
1797 * bucket of the routing table (so core won't disconnect them!)
1800 schedule_ping_messages ()
1802 unsigned int bucket;
1804 struct PeerInfo *pos;
1805 for (bucket = lowest_bucket; bucket < MAX_BUCKETS; bucket++)
1807 pos = k_buckets[bucket].head;
1811 if ((count < bucket_size)
1812 && (pos->ping_task == GNUNET_SCHEDULER_NO_TASK))
1813 GNUNET_SCHEDULER_add_now (&periodic_ping_task, pos);
1814 else if ((count >= bucket_size)
1815 && (pos->ping_task != GNUNET_SCHEDULER_NO_TASK))
1817 GNUNET_SCHEDULER_cancel (pos->ping_task);
1818 pos->ping_task = GNUNET_SCHEDULER_NO_TASK;
1828 * Attempt to add a peer to our k-buckets.
1830 * @param peer the peer identity of the peer being added
1831 * @param bucket the bucket that we want this peer to go in
1832 * @param atsi transport ATS information
1834 * @return NULL if the peer was not added,
1835 * pointer to PeerInfo for new peer otherwise
1837 static struct PeerInfo *
1838 try_add_peer (const struct GNUNET_PeerIdentity *peer,
1839 unsigned int bucket,
1840 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
1843 struct PeerInfo *new_peer;
1845 if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
1848 peer_bucket = find_current_bucket (&peer->hashPubKey);
1850 GNUNET_assert (peer_bucket >= lowest_bucket);
1851 new_peer = add_peer (peer, peer_bucket, atsi);
1853 if ((k_buckets[lowest_bucket].peers_size) >= bucket_size)
1854 enable_next_bucket ();
1856 schedule_ping_messages ();
1863 * Task run to check for messages that need to be sent to a client.
1865 * @param client a ClientList, containing the client and any messages to be sent to it
1868 process_pending_messages (struct ClientList *client)
1870 if (client->pending_head == NULL)
1872 if (client->transmit_handle != NULL)
1875 client->transmit_handle =
1876 GNUNET_SERVER_notify_transmit_ready (client->client_handle,
1877 ntohs (client->pending_head->
1879 GNUNET_TIME_UNIT_FOREVER_REL,
1880 &send_generic_reply, client);
1884 * Callback called as a result of issuing a GNUNET_SERVER_notify_transmit_ready
1885 * request. A ClientList is passed as closure, take the head of the list
1886 * and copy it into buf, which has the result of sending the message to the
1889 * @param cls closure to this call
1890 * @param size maximum number of bytes available to send
1891 * @param buf where to copy the actual message to
1893 * @return the number of bytes actually copied, 0 indicates failure
1896 send_generic_reply (void *cls, size_t size, void *buf)
1898 struct ClientList *client = cls;
1900 struct PendingMessage *reply;
1904 client->transmit_handle = NULL;
1907 /* client disconnected */
1911 while ((NULL != (reply = client->pending_head)) &&
1912 (size >= off + (msize = ntohs (reply->msg->size))))
1914 GNUNET_CONTAINER_DLL_remove (client->pending_head,
1915 client->pending_tail, reply);
1916 memcpy (&cbuf[off], reply->msg, msize);
1917 GNUNET_free (reply);
1920 process_pending_messages (client);
1922 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1923 "Transmitted %u bytes of replies to client\n",
1924 (unsigned int) off);
1931 * Add a PendingMessage to the clients list of messages to be sent
1933 * @param client the active client to send the message to
1934 * @param pending_message the actual message to send
1937 add_pending_message (struct ClientList *client,
1938 struct PendingMessage *pending_message)
1940 GNUNET_CONTAINER_DLL_insert_after (client->pending_head,
1941 client->pending_tail,
1942 client->pending_tail, pending_message);
1943 process_pending_messages (client);
1948 * Called when a reply needs to be sent to a client, as
1949 * a result it found to a GET or FIND PEER request.
1951 * @param client the client to send the reply to
1952 * @param message the encapsulated message to send
1953 * @param uid the unique identifier of this request
1957 send_reply_to_client (struct ClientList *client,
1958 const struct GNUNET_MessageHeader *message,
1959 unsigned long long uid, const GNUNET_HashCode * key)
1961 struct GNUNET_DHT_RouteResultMessage *reply;
1962 struct PendingMessage *pending_message;
1966 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1967 "`%s:%s': Sending reply to client.\n", my_short_id, "DHT");
1969 msize = ntohs (message->size);
1970 tsize = sizeof (struct GNUNET_DHT_RouteResultMessage) + msize;
1971 if (tsize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
1973 GNUNET_break_op (0);
1976 pending_message = GNUNET_malloc (sizeof (struct PendingMessage) + tsize);
1977 pending_message->msg = (struct GNUNET_MessageHeader *) &pending_message[1];
1978 reply = (struct GNUNET_DHT_RouteResultMessage *) &pending_message[1];
1979 reply->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_LOCAL_ROUTE_RESULT);
1980 reply->header.size = htons (tsize);
1981 reply->put_path_length = htons (0); /* FIXME: implement */
1982 reply->get_path_length = htons (0); /* FIXME: implement */
1983 reply->unique_id = GNUNET_htonll (uid);
1985 memcpy (&reply[1], message, msize);
1986 add_pending_message (client, pending_message);
1990 * Consider whether or not we would like to have this peer added to
1991 * our routing table. Check whether bucket for this peer is full,
1992 * if so return negative; if not return positive. Since peers are
1993 * only added on CORE level connect, this doesn't actually add the
1994 * peer to the routing table.
1996 * @param peer the peer we are considering adding
1998 * @return GNUNET_YES if we want this peer, GNUNET_NO if not (bucket
2002 consider_peer (struct GNUNET_PeerIdentity *peer)
2007 GNUNET_CONTAINER_multihashmap_contains (all_known_peers,
2010 memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity))))
2011 return GNUNET_NO; /* We already know this peer (are connected even!) */
2012 bucket = find_current_bucket (&peer->hashPubKey);
2014 if ((k_buckets[bucket].peers_size < bucket_size)
2015 || ((bucket == lowest_bucket) && (lowest_bucket > 0)))
2023 * Task used to remove forwarding entries, either
2024 * after timeout, when full, or on shutdown.
2026 * @param cls the entry to remove
2027 * @param tc context, reason, etc.
2030 remove_forward_entry (void *cls,
2031 const struct GNUNET_SCHEDULER_TaskContext *tc)
2033 struct DHTRouteSource *source_info = cls;
2034 struct DHTQueryRecord *record;
2036 GNUNET_CONTAINER_heap_remove_node (forward_list.minHeap,
2037 source_info->hnode);
2038 record = source_info->record;
2039 GNUNET_CONTAINER_DLL_remove (record->head, record->tail, source_info);
2041 if (record->head == NULL) /* No more entries in DLL */
2043 GNUNET_assert (GNUNET_YES ==
2044 GNUNET_CONTAINER_multihashmap_remove
2045 (forward_list.hashmap, &record->key, record));
2046 GNUNET_free (record);
2048 if (source_info->find_peers_responded != NULL)
2049 GNUNET_CONTAINER_bloomfilter_free (source_info->find_peers_responded);
2050 GNUNET_free (source_info);
2054 * Main function that handles whether or not to route a result
2055 * message to other peers, or to send to our local client.
2057 * @param msg the result message to be routed
2058 * @param msg_ctx context of the message we are routing
2060 * @return the number of peers the message was routed to,
2061 * GNUNET_SYSERR on failure
2064 route_result_message (struct GNUNET_MessageHeader *msg,
2065 struct DHT_MessageContext *msg_ctx)
2067 struct GNUNET_PeerIdentity new_peer;
2068 struct DHTQueryRecord *record;
2069 struct DHTRouteSource *pos;
2070 struct PeerInfo *peer_info;
2071 const struct GNUNET_MessageHeader *hello_msg;
2073 increment_stats (STAT_RESULTS);
2075 * If a find peer result message is received and contains a valid
2076 * HELLO for another peer, offer it to the transport service.
2078 if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DHT_FIND_PEER_RESULT)
2080 if (ntohs (msg->size) <= sizeof (struct GNUNET_MessageHeader))
2081 GNUNET_break_op (0);
2083 hello_msg = &msg[1];
2084 if ((ntohs (hello_msg->type) != GNUNET_MESSAGE_TYPE_HELLO)
2085 || (GNUNET_SYSERR ==
2086 GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *)
2087 hello_msg, &new_peer)))
2089 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2090 "%s:%s Received non-HELLO message type in find peer result message!\n",
2091 my_short_id, "DHT");
2092 GNUNET_break_op (0);
2095 else /* We have a valid hello, and peer id stored in new_peer */
2097 find_peer_context.count++;
2098 increment_stats (STAT_FIND_PEER_REPLY);
2099 if (GNUNET_YES == consider_peer (&new_peer))
2101 increment_stats (STAT_HELLOS_PROVIDED);
2102 GNUNET_TRANSPORT_offer_hello (transport_handle, hello_msg);
2103 GNUNET_CORE_peer_request_connect (coreAPI,
2104 GNUNET_TIME_relative_multiply
2105 (GNUNET_TIME_UNIT_SECONDS, 5),
2106 &new_peer, NULL, NULL);
2111 if (malicious_dropper == GNUNET_YES)
2115 GNUNET_CONTAINER_multihashmap_get (forward_list.hashmap, &msg_ctx->key);
2117 if (record == NULL) /* No record of this message! */
2120 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2121 "`%s:%s': Have no record of response key %s uid %llu\n",
2122 my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key),
2123 msg_ctx->unique_id);
2125 #if DEBUG_DHT_ROUTING
2126 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2128 dhtlog_handle->insert_route (NULL,
2134 &msg_ctx->key, msg_ctx->peer, NULL);
2137 if (msg_ctx->bloom != NULL)
2139 GNUNET_CONTAINER_bloomfilter_free (msg_ctx->bloom);
2140 msg_ctx->bloom = NULL;
2148 #if STRICT_FORWARDING
2149 if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DHT_FIND_PEER_RESULT) /* If we have already forwarded this peer id, don't do it again! */
2152 GNUNET_CONTAINER_bloomfilter_test (pos->find_peers_responded,
2153 &new_peer.hashPubKey))
2156 ("# find peer responses NOT forwarded (bloom match)");
2161 GNUNET_CONTAINER_bloomfilter_add (pos->find_peers_responded,
2162 &new_peer.hashPubKey);
2166 if (0 == memcmp (&pos->source, &my_identity, sizeof (struct GNUNET_PeerIdentity))) /* Local client (or DHT) initiated request! */
2169 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2170 "`%s:%s': Sending response key %s uid %llu to client\n",
2171 my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key),
2172 msg_ctx->unique_id);
2174 #if DEBUG_DHT_ROUTING
2175 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2177 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id,
2178 DHTLOG_RESULT, msg_ctx->hop_count,
2179 GNUNET_YES, &my_identity,
2180 &msg_ctx->key, msg_ctx->peer,
2184 increment_stats (STAT_RESULTS_TO_CLIENT);
2185 if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DHT_GET_RESULT)
2186 increment_stats (STAT_GET_REPLY);
2188 send_reply_to_client (pos->client, msg,
2189 msg_ctx->unique_id, &msg_ctx->key);
2191 else /* Send to peer */
2193 peer_info = find_peer_by_id (&pos->source);
2194 if (peer_info == NULL) /* Didn't find the peer in our routing table, perhaps peer disconnected! */
2200 if (msg_ctx->bloom == NULL)
2202 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
2204 GNUNET_CONTAINER_bloomfilter_add (msg_ctx->bloom,
2205 &my_identity.hashPubKey);
2207 GNUNET_CONTAINER_bloomfilter_test (msg_ctx->bloom,
2208 &peer_info->id.hashPubKey)))
2211 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2212 "`%s:%s': Forwarding response key %s uid %llu to peer %s\n",
2213 my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key),
2214 msg_ctx->unique_id, GNUNET_i2s (&peer_info->id));
2216 #if DEBUG_DHT_ROUTING
2217 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2219 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id,
2222 GNUNET_NO, &my_identity,
2223 &msg_ctx->key, msg_ctx->peer,
2227 forward_result_message (msg, peer_info, msg_ctx);
2228 /* Try removing forward entries after sending once, only allows ONE response per request */
2229 if (pos->delete_task != GNUNET_SCHEDULER_NO_TASK)
2231 GNUNET_SCHEDULER_cancel (pos->delete_task);
2233 GNUNET_SCHEDULER_add_now (&remove_forward_entry, pos);
2239 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2240 "`%s:%s': NOT Forwarding response (bloom match) key %s uid %llu to peer %s\n",
2241 my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key),
2242 msg_ctx->unique_id, GNUNET_i2s (&peer_info->id));
2248 if (msg_ctx->bloom != NULL)
2250 GNUNET_CONTAINER_bloomfilter_free (msg_ctx->bloom);
2251 msg_ctx->bloom = NULL;
2257 * Iterator for local get request results,
2259 * @param cls closure for iterator, a DatacacheGetContext
2260 * @param exp when does this value expire?
2261 * @param key the key this data is stored under
2262 * @param size the size of the data identified by key
2263 * @param data the actual data
2264 * @param type the type of the data
2266 * @return GNUNET_OK to continue iteration, anything else
2267 * to stop iteration.
2270 datacache_get_iterator (void *cls,
2271 struct GNUNET_TIME_Absolute exp,
2272 const GNUNET_HashCode * key,
2273 size_t size, const char *data,
2274 enum GNUNET_BLOCK_Type type)
2276 struct DHT_MessageContext *msg_ctx = cls;
2277 struct DHT_MessageContext *new_msg_ctx;
2278 struct GNUNET_DHT_GetResultMessage *get_result;
2279 enum GNUNET_BLOCK_EvaluationResult eval;
2282 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2283 "`%s:%s': Received `%s' response from datacache\n", my_short_id,
2286 eval = GNUNET_BLOCK_evaluate (block_context,
2290 msg_ctx->reply_bf_mutator,
2292 msg_ctx->xquery_size, data, size);
2295 case GNUNET_BLOCK_EVALUATION_OK_LAST:
2296 msg_ctx->do_forward = GNUNET_NO;
2297 case GNUNET_BLOCK_EVALUATION_OK_MORE:
2298 new_msg_ctx = GNUNET_malloc (sizeof (struct DHT_MessageContext));
2299 memcpy (new_msg_ctx, msg_ctx, sizeof (struct DHT_MessageContext));
2301 GNUNET_malloc (sizeof (struct GNUNET_DHT_GetResultMessage) + size);
2302 get_result->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_GET_RESULT);
2303 get_result->header.size =
2304 htons (sizeof (struct GNUNET_DHT_GetResultMessage) + size);
2305 get_result->expiration = GNUNET_TIME_absolute_hton (exp);
2306 get_result->type = htons (type);
2307 memcpy (&get_result[1], data, size);
2308 new_msg_ctx->peer = &my_identity;
2309 new_msg_ctx->bloom =
2310 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K);
2311 new_msg_ctx->hop_count = 0;
2312 new_msg_ctx->importance = DHT_DEFAULT_P2P_IMPORTANCE + 2; /* Make result routing a higher priority */
2313 new_msg_ctx->timeout = DHT_DEFAULT_P2P_TIMEOUT;
2314 increment_stats (STAT_GET_RESPONSE_START);
2315 route_result_message (&get_result->header, new_msg_ctx);
2316 GNUNET_free (new_msg_ctx);
2317 GNUNET_free (get_result);
2319 case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE:
2321 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2322 "`%s:%s': Duplicate block error\n", my_short_id, "DHT");
2325 case GNUNET_BLOCK_EVALUATION_RESULT_INVALID:
2327 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2328 "`%s:%s': Invalid request error\n", my_short_id, "DHT");
2331 case GNUNET_BLOCK_EVALUATION_REQUEST_VALID:
2333 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2334 "`%s:%s': Valid request, no results.\n", my_short_id,
2339 case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID:
2340 GNUNET_break_op (0);
2341 msg_ctx->do_forward = GNUNET_NO;
2343 case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED:
2345 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2346 "`%s:%s': Unsupported block type (%u) in response!\n",
2347 my_short_id, "DHT", type);
2349 /* msg_ctx->do_forward = GNUNET_NO; // not sure... */
2357 * Main function that handles whether or not to route a message to other
2360 * @param msg the message to be routed
2361 * @param msg_ctx the context containing all pertinent information about the message
2364 route_message (const struct GNUNET_MessageHeader *msg,
2365 struct DHT_MessageContext *msg_ctx);
2369 * Server handler for all dht get requests, look for data,
2370 * if found, send response either to clients or other peers.
2372 * @param msg the actual get message
2373 * @param msg_ctx struct containing pertinent information about the get request
2375 * @return number of items found for GET request
2378 handle_dht_get (const struct GNUNET_MessageHeader *msg,
2379 struct DHT_MessageContext *msg_ctx)
2381 const struct GNUNET_DHT_GetMessage *get_msg;
2384 unsigned int results;
2386 enum GNUNET_BLOCK_Type type;
2388 msize = ntohs (msg->size);
2389 if (msize < sizeof (struct GNUNET_DHT_GetMessage))
2394 get_msg = (const struct GNUNET_DHT_GetMessage *) msg;
2395 bf_size = ntohs (get_msg->bf_size);
2396 msg_ctx->xquery_size = ntohs (get_msg->xquery_size);
2397 msg_ctx->reply_bf_mutator = get_msg->bf_mutator; /* FIXME: ntohl? */
2399 sizeof (struct GNUNET_DHT_GetMessage) + bf_size + msg_ctx->xquery_size)
2404 end = (const char *) &get_msg[1];
2405 if (msg_ctx->xquery_size == 0)
2407 msg_ctx->xquery = NULL;
2411 msg_ctx->xquery = (const void *) end;
2412 end += msg_ctx->xquery_size;
2416 msg_ctx->reply_bf = NULL;
2420 msg_ctx->reply_bf = GNUNET_CONTAINER_bloomfilter_init (end,
2422 GNUNET_DHT_GET_BLOOMFILTER_K);
2424 type = (enum GNUNET_BLOCK_Type) ntohl (get_msg->type);
2426 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2427 "`%s:%s': Received `%s' request, message type %u, key %s, uid %llu\n",
2430 type, GNUNET_h2s (&msg_ctx->key), msg_ctx->unique_id);
2432 increment_stats (STAT_GETS);
2435 if (type == GNUNET_BLOCK_DHT_MALICIOUS_MESSAGE_TYPE)
2437 GNUNET_CONTAINER_bloomfilter_free (msg_ctx->reply_bf);
2441 msg_ctx->do_forward = GNUNET_YES;
2442 if (datacache != NULL)
2444 = GNUNET_DATACACHE_get (datacache,
2445 &msg_ctx->key, type,
2446 &datacache_get_iterator, msg_ctx);
2448 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2449 "`%s:%s': Found %d results for `%s' request uid %llu\n",
2450 my_short_id, "DHT", results, "GET", msg_ctx->unique_id);
2454 #if DEBUG_DHT_ROUTING
2455 if ((debug_routes) && (dhtlog_handle != NULL))
2457 dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_GET,
2458 msg_ctx->hop_count, GNUNET_YES,
2459 &my_identity, &msg_ctx->key);
2462 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2464 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE,
2465 msg_ctx->hop_count, GNUNET_YES,
2466 &my_identity, &msg_ctx->key,
2467 msg_ctx->peer, NULL);
2473 /* check query valid */
2474 if (GNUNET_BLOCK_EVALUATION_REQUEST_INVALID
2475 == GNUNET_BLOCK_evaluate (block_context,
2479 msg_ctx->reply_bf_mutator,
2481 msg_ctx->xquery_size, NULL, 0))
2483 GNUNET_break_op (0);
2484 msg_ctx->do_forward = GNUNET_NO;
2488 if (msg_ctx->hop_count == 0) /* Locally initiated request */
2490 #if DEBUG_DHT_ROUTING
2491 if ((debug_routes) && (dhtlog_handle != NULL))
2493 dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_GET,
2494 msg_ctx->hop_count, GNUNET_NO,
2495 &my_identity, &msg_ctx->key);
2499 if (msg_ctx->do_forward == GNUNET_YES)
2500 route_message (msg, msg_ctx);
2501 GNUNET_CONTAINER_bloomfilter_free (msg_ctx->reply_bf);
2506 remove_recent_find_peer (void *cls,
2507 const struct GNUNET_SCHEDULER_TaskContext *tc)
2509 GNUNET_HashCode *key = cls;
2511 GNUNET_assert (GNUNET_YES ==
2512 GNUNET_CONTAINER_multihashmap_remove
2513 (recent_find_peer_requests, key, NULL));
2518 * Server handler for initiating local dht find peer requests
2520 * @param find_msg the actual find peer message
2521 * @param msg_ctx struct containing pertinent information about the request
2525 handle_dht_find_peer (const struct GNUNET_MessageHeader *find_msg,
2526 struct DHT_MessageContext *msg_ctx)
2528 struct GNUNET_MessageHeader *find_peer_result;
2529 struct GNUNET_DHT_FindPeerMessage *find_peer_message;
2530 struct DHT_MessageContext *new_msg_ctx;
2531 struct GNUNET_CONTAINER_BloomFilter *incoming_bloom;
2534 GNUNET_HashCode *recent_hash;
2535 struct GNUNET_MessageHeader *other_hello;
2536 size_t other_hello_size;
2537 struct GNUNET_PeerIdentity peer_id;
2539 find_peer_message = (struct GNUNET_DHT_FindPeerMessage *) find_msg;
2540 GNUNET_break_op (ntohs (find_msg->size) >=
2541 (sizeof (struct GNUNET_DHT_FindPeerMessage)));
2542 if (ntohs (find_msg->size) < sizeof (struct GNUNET_DHT_FindPeerMessage))
2545 other_hello_size = 0;
2546 if (ntohs (find_msg->size) > sizeof (struct GNUNET_DHT_FindPeerMessage))
2549 ntohs (find_msg->size) - sizeof (struct GNUNET_DHT_FindPeerMessage);
2550 other_hello = GNUNET_malloc (other_hello_size);
2551 memcpy (other_hello, &find_peer_message[1], other_hello_size);
2552 if ((GNUNET_HELLO_size ((struct GNUNET_HELLO_Message *) other_hello) ==
2555 GNUNET_HELLO_get_id ((struct GNUNET_HELLO_Message *)
2556 other_hello, &peer_id)))
2558 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
2559 "Received invalid HELLO message in find peer request!\n");
2560 GNUNET_free (other_hello);
2563 #if FIND_PEER_WITH_HELLO
2564 if (GNUNET_YES == consider_peer (&peer_id))
2566 increment_stats (STAT_HELLOS_PROVIDED);
2567 GNUNET_TRANSPORT_offer_hello (transport_handle, other_hello);
2568 GNUNET_CORE_peer_request_connect (coreAPI,
2569 GNUNET_TIME_relative_multiply
2570 (GNUNET_TIME_UNIT_SECONDS, 5),
2571 &peer_id, NULL, NULL);
2572 route_message (find_msg, msg_ctx);
2573 GNUNET_free (other_hello);
2576 else /* We don't want this peer! */
2578 route_message (find_msg, msg_ctx);
2579 GNUNET_free (other_hello);
2586 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2587 "`%s:%s': Received `%s' request from client, key %s (msg size %d, we expected %d)\n",
2588 my_short_id, "DHT", "FIND PEER", GNUNET_h2s (&msg_ctx->key),
2589 ntohs (find_msg->size), sizeof (struct GNUNET_MessageHeader));
2591 if (my_hello == NULL)
2594 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2595 "`%s': Our HELLO is null, can't return.\n", "DHT");
2597 GNUNET_free_non_null (other_hello);
2598 route_message (find_msg, msg_ctx);
2603 GNUNET_CONTAINER_bloomfilter_init (find_peer_message->bloomfilter,
2604 DHT_BLOOM_SIZE, DHT_BLOOM_K);
2606 GNUNET_CONTAINER_bloomfilter_test (incoming_bloom,
2607 &my_identity.hashPubKey))
2609 increment_stats (STAT_BLOOM_FIND_PEER);
2610 GNUNET_CONTAINER_bloomfilter_free (incoming_bloom);
2611 GNUNET_free_non_null (other_hello);
2612 route_message (find_msg, msg_ctx);
2613 return; /* We match the bloomfilter, do not send a response to this peer (they likely already know us!) */
2615 GNUNET_CONTAINER_bloomfilter_free (incoming_bloom);
2617 #if RESTRICT_FIND_PEER
2620 * Ignore any find peer requests from a peer we have seen very recently.
2622 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! */
2624 increment_stats ("# dht find peer requests ignored (recently seen!)");
2625 GNUNET_free_non_null (other_hello);
2630 * Use this check to only allow the peer to respond to find peer requests if
2631 * it would be beneficial to have the requesting peer in this peers routing
2632 * table. Can be used to thwart peers flooding the network with find peer
2633 * requests that we don't care about. However, if a new peer is joining
2634 * the network and has no other peers this is a problem (assume all buckets
2635 * full, no one will respond!).
2637 memcpy (&peer_id.hashPubKey, &msg_ctx->key, sizeof (GNUNET_HashCode));
2638 if (GNUNET_NO == consider_peer (&peer_id))
2640 increment_stats ("# dht find peer requests ignored (do not need!)");
2641 GNUNET_free_non_null (other_hello);
2642 route_message (find_msg, msg_ctx);
2647 recent_hash = GNUNET_malloc (sizeof (GNUNET_HashCode));
2648 memcpy (recent_hash, &msg_ctx->key, sizeof (GNUNET_HashCode));
2649 if (GNUNET_SYSERR !=
2650 GNUNET_CONTAINER_multihashmap_put (recent_find_peer_requests,
2651 &msg_ctx->key, NULL,
2652 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
2654 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2655 "Adding recent remove task for key `%s`!\n",
2656 GNUNET_h2s (&msg_ctx->key));
2657 /* Only add a task if there wasn't one for this key already! */
2658 GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_relative_multiply
2659 (GNUNET_TIME_UNIT_SECONDS, 30),
2660 &remove_recent_find_peer, recent_hash);
2664 GNUNET_free (recent_hash);
2665 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2666 "Received duplicate find peer request too soon!\n");
2669 /* Simplistic find_peer functionality, always return our hello */
2670 hello_size = ntohs (my_hello->size);
2671 tsize = hello_size + sizeof (struct GNUNET_MessageHeader);
2673 if (tsize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
2675 GNUNET_break_op (0);
2676 GNUNET_free_non_null (other_hello);
2680 find_peer_result = GNUNET_malloc (tsize);
2681 find_peer_result->type = htons (GNUNET_MESSAGE_TYPE_DHT_FIND_PEER_RESULT);
2682 find_peer_result->size = htons (tsize);
2683 memcpy (&find_peer_result[1], my_hello, hello_size);
2685 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2686 "`%s': Sending hello size %d to requesting peer.\n",
2689 new_msg_ctx = GNUNET_malloc (sizeof (struct DHT_MessageContext));
2690 memcpy (new_msg_ctx, msg_ctx, sizeof (struct DHT_MessageContext));
2691 new_msg_ctx->peer = &my_identity;
2692 new_msg_ctx->bloom =
2693 GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K);
2694 new_msg_ctx->hop_count = 0;
2695 new_msg_ctx->importance = DHT_DEFAULT_P2P_IMPORTANCE + 2; /* Make find peer requests a higher priority */
2696 new_msg_ctx->timeout = DHT_DEFAULT_P2P_TIMEOUT;
2697 increment_stats (STAT_FIND_PEER_ANSWER);
2698 route_result_message (find_peer_result, new_msg_ctx);
2699 GNUNET_free (new_msg_ctx);
2700 #if DEBUG_DHT_ROUTING
2701 if ((debug_routes) && (dhtlog_handle != NULL))
2703 dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_FIND_PEER,
2704 msg_ctx->hop_count, GNUNET_YES,
2705 &my_identity, &msg_ctx->key);
2708 GNUNET_free_non_null (other_hello);
2709 GNUNET_free (find_peer_result);
2710 route_message (find_msg, msg_ctx);
2714 * Task used to republish data.
2715 * Forward declaration; function call loop.
2717 * @param cls closure (a struct RepublishContext)
2718 * @param tc runtime context for this task
2721 republish_content (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
2724 * Server handler for initiating local dht put requests
2726 * @param msg the actual put message
2727 * @param msg_ctx struct containing pertinent information about the request
2730 handle_dht_put (const struct GNUNET_MessageHeader *msg,
2731 struct DHT_MessageContext *msg_ctx)
2733 const struct GNUNET_DHT_PutMessage *put_msg;
2734 enum GNUNET_BLOCK_Type put_type;
2737 struct RepublishContext *put_context;
2738 GNUNET_HashCode key;
2740 GNUNET_assert (ntohs (msg->size) >= sizeof (struct GNUNET_DHT_PutMessage));
2743 put_msg = (const struct GNUNET_DHT_PutMessage *) msg;
2744 put_type = (enum GNUNET_BLOCK_Type) ntohl (put_msg->type);
2746 if (put_type == GNUNET_BLOCK_DHT_MALICIOUS_MESSAGE_TYPE)
2748 #if DEBUG_DHT_ROUTING
2749 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2751 /** Log routes that die due to high load! */
2752 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE,
2753 msg_ctx->hop_count, GNUNET_SYSERR,
2754 &my_identity, &msg_ctx->key,
2755 msg_ctx->peer, NULL);
2762 ntohs (put_msg->header.size) - sizeof (struct GNUNET_DHT_PutMessage);
2764 GNUNET_BLOCK_get_key (block_context, put_type, &put_msg[1], data_size,
2766 if (GNUNET_NO == ret)
2768 #if DEBUG_DHT_ROUTING
2769 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2771 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE,
2772 msg_ctx->hop_count, GNUNET_SYSERR,
2773 &my_identity, &msg_ctx->key,
2774 msg_ctx->peer, NULL);
2778 GNUNET_break_op (0);
2781 if ((GNUNET_YES == ret) &&
2782 (0 != memcmp (&key, &msg_ctx->key, sizeof (GNUNET_HashCode))))
2784 #if DEBUG_DHT_ROUTING
2785 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2787 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE,
2788 msg_ctx->hop_count, GNUNET_SYSERR,
2789 &my_identity, &msg_ctx->key,
2790 msg_ctx->peer, NULL);
2793 /* invalid wrapper: key mismatch! */
2794 GNUNET_break_op (0);
2797 /* ret == GNUNET_SYSERR means that there is no known relationship between
2798 data and the key, so we cannot check it */
2800 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2801 "`%s:%s': Received `%s' request (inserting data!), message type %d, key %s, uid %llu\n",
2802 my_short_id, "DHT", "PUT", put_type, GNUNET_h2s (&msg_ctx->key),
2803 msg_ctx->unique_id);
2805 #if DEBUG_DHT_ROUTING
2806 if (msg_ctx->hop_count == 0) /* Locally initiated request */
2808 if ((debug_routes) && (dhtlog_handle != NULL))
2810 dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_PUT,
2811 msg_ctx->hop_count, GNUNET_NO,
2812 &my_identity, &msg_ctx->key);
2817 if (msg_ctx->closest != GNUNET_YES)
2819 route_message (msg, msg_ctx);
2824 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2825 "`%s:%s': Received `%s' request (inserting data!), message type %d, key %s, uid %llu\n",
2826 my_short_id, "DHT", "PUT", put_type, GNUNET_h2s (&msg_ctx->key),
2827 msg_ctx->unique_id);
2830 #if DEBUG_DHT_ROUTING
2831 if ((debug_routes_extended) && (dhtlog_handle != NULL))
2833 dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE,
2834 msg_ctx->hop_count, GNUNET_YES,
2835 &my_identity, &msg_ctx->key, msg_ctx->peer,
2839 if ((debug_routes) && (dhtlog_handle != NULL))
2841 dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_PUT,
2842 msg_ctx->hop_count, GNUNET_YES,
2843 &my_identity, &msg_ctx->key);
2847 increment_stats (STAT_PUTS_INSERTED);
2848 if (datacache != NULL)
2850 ret = GNUNET_DATACACHE_put (datacache, &msg_ctx->key, data_size,
2851 (char *) &put_msg[1], put_type,
2852 GNUNET_TIME_absolute_ntoh
2853 (put_msg->expiration));
2855 if ((ret == GNUNET_YES) && (do_republish == GNUNET_YES))
2857 put_context = GNUNET_malloc (sizeof (struct RepublishContext));
2858 memcpy (&put_context->key, &msg_ctx->key, sizeof (GNUNET_HashCode));
2859 put_context->type = put_type;
2860 GNUNET_SCHEDULER_add_delayed (dht_republish_frequency,
2861 &republish_content, put_context);
2865 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2866 "`%s:%s': %s request received, but have no datacache!\n",
2867 my_short_id, "DHT", "PUT");
2869 if (stop_on_closest == GNUNET_NO)
2870 route_message (msg, msg_ctx);
2874 * Estimate the diameter of the network based
2875 * on how many buckets are currently in use.
2876 * Concept here is that the diameter of the network
2877 * is roughly the distance a message must travel in
2878 * order to reach its intended destination. Since
2879 * at each hop we expect to get one bit closer, and
2880 * we have one bit per bucket, the number of buckets
2881 * in use should be the largest number of hops for
2882 * a successful message. (of course, this assumes we
2883 * know all peers in the network!)
2885 * @return ballpark diameter figure
2888 estimate_diameter ()
2890 return MAX_BUCKETS - lowest_bucket;
2894 * To how many peers should we (on average)
2895 * forward the request to obtain the desired
2896 * target_replication count (on average).
2898 * returns: target_replication / (est. hops) + (target_replication * hop_count)
2899 * where est. hops is typically 2 * the routing table depth
2901 * @param hop_count number of hops the message has traversed
2902 * @param target_replication the number of total paths desired
2904 * @return Some number of peers to forward the message to
2907 get_forward_count (unsigned int hop_count, size_t target_replication)
2909 uint32_t random_value;
2910 unsigned int forward_count;
2912 unsigned int diameter;
2914 diameter = estimate_diameter ();
2916 if (GNUNET_NO == use_max_hops)
2917 max_hops = (diameter + 1) * 2;
2920 * If we are behaving in strict kademlia mode, send multiple initial requests,
2921 * but then only send to 1 or 0 peers based strictly on the number of hops.
2923 if (strict_kademlia == GNUNET_YES)
2926 return kademlia_replication;
2927 else if (hop_count < max_hops)
2933 /* FIXME: the smaller we think the network is the more lenient we should be for
2934 * routing right? The estimation below only works if we think we have reasonably
2935 * full routing tables, which for our RR topologies may not be the case!
2937 if (hop_count > max_hops)
2940 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2941 "`%s:%s': Hop count too high (est %d, lowest %d), NOT Forwarding request\n",
2942 my_short_id, "DHT", estimate_diameter (), lowest_bucket);
2950 target_replication / (diameter +
2951 ((float) target_replication * hop_count));
2952 if (target_value > 1)
2954 /* Set forward count to floor of target_value */
2955 forward_count = (unsigned int) target_value;
2956 /* Subtract forward_count (floor) from target_value (yields value between 0 and 1) */
2957 target_value = target_value - forward_count;
2961 GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_STRONG,
2964 if (random_value < (target_value * UINT32_MAX))
2967 return forward_count;
2971 * Check whether my identity is closer than any known peers.
2972 * If a non-null bloomfilter is given, check if this is the closest
2973 * peer that hasn't already been routed to.
2975 * @param target hash code to check closeness to
2976 * @param bloom bloomfilter, exclude these entries from the decision
2978 * Return GNUNET_YES if node location is closest, GNUNET_NO
2982 am_closest_peer (const GNUNET_HashCode * target,
2983 struct GNUNET_CONTAINER_BloomFilter *bloom)
2989 struct PeerInfo *pos;
2990 unsigned int my_distance;
2992 if (0 == memcmp (&my_identity.hashPubKey, target, sizeof (GNUNET_HashCode)))
2995 bucket_num = find_current_bucket (target);
2997 bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, target);
2998 my_distance = distance (&my_identity.hashPubKey, target);
2999 pos = k_buckets[bucket_num].head;
3001 while ((pos != NULL) && (count < bucket_size))
3005 GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)))
3008 continue; /* Skip already checked entries */
3012 GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey, target);
3013 if (other_bits > bits)
3015 else if (other_bits == bits) /* We match the same number of bits */
3017 if (strict_kademlia != GNUNET_YES) /* Return that we at as close as any other peer */
3019 else if (distance (&pos->id.hashPubKey, target) < my_distance) /* Check all known peers, only return if we are the true closest */
3025 /* No peers closer, we are the closest! */
3031 * Return this peers adjusted value based on the convergence
3032 * function chosen. This is the key function for randomized
3033 * routing decisions.
3035 * @param target the key of the request
3036 * @param peer the peer we would like the value of
3037 * @param hops number of hops this message has already traveled
3039 * @return bit distance from target to peer raised to an exponent
3040 * adjusted based on the current routing convergence algorithm
3043 static unsigned long long
3044 converge_distance (const GNUNET_HashCode * target,
3045 struct PeerInfo *peer, unsigned int hops)
3047 unsigned long long ret;
3048 unsigned int other_matching_bits;
3049 double base_converge_modifier = .1; /* Value that "looks" good (when plotted), have to start somewhere */
3050 double temp_modifier;
3056 curr_max_hops = max_hops;
3058 curr_max_hops = (estimate_diameter () + 1) * 2;
3060 if (converge_modifier > 0)
3061 temp_modifier = converge_modifier * base_converge_modifier;
3064 temp_modifier = base_converge_modifier;
3065 base_converge_modifier = 0.0;
3068 GNUNET_assert (temp_modifier > 0);
3070 other_matching_bits =
3071 GNUNET_CRYPTO_hash_matching_bits (target, &peer->id.hashPubKey);
3073 switch (converge_option)
3075 case DHT_CONVERGE_RANDOM:
3076 return 1; /* Always return 1, choose equally among all peers */
3077 case DHT_CONVERGE_LINEAR:
3078 calc_value = hops * curr_max_hops * temp_modifier;
3080 case DHT_CONVERGE_SQUARE:
3082 * Simple square based curve.
3085 (sqrt (hops) / sqrt (curr_max_hops)) * (curr_max_hops /
3089 case DHT_CONVERGE_EXPONENTIAL:
3091 * Simple exponential curve.
3093 if (base_converge_modifier > 0)
3094 calc_value = (temp_modifier * hops * hops) / curr_max_hops;
3096 calc_value = (hops * hops) / curr_max_hops;
3098 case DHT_CONVERGE_BINARY:
3100 * If below the cutoff, route randomly (return 1),
3101 * If above the cutoff, return the maximum possible
3102 * value first (always route to closest, because
3106 if (hops >= converge_modifier) /* Past cutoff */
3115 /* Take the log (base e) of the number of bits matching the other peer */
3116 exponent = log (other_matching_bits);
3118 /* Check if we would overflow; our largest possible value is 2^64 approx. e^44.361419555836498 */
3119 if (exponent * calc_value >= 44.361419555836498)
3122 /* Clear errno and all math exceptions */
3124 feclearexcept (FE_ALL_EXCEPT);
3125 ret = (unsigned long long) pow (other_matching_bits, calc_value);
3126 if ((errno != 0) || fetestexcept (FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW |
3129 if (0 != fetestexcept (FE_OVERFLOW))
3130 GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "FE_OVERFLOW\n");
3131 if (0 != fetestexcept (FE_INVALID))
3132 GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "FE_INVALID\n");
3133 if (0 != fetestexcept (FE_UNDERFLOW))
3134 GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "FE_UNDERFLOW\n");
3142 * Comparison function for two struct PeerInfo's
3143 * which have already had their matching bits to
3144 * some target calculated.
3146 * @param p1 a pointer pointer to a struct PeerInfo
3147 * @param p2 a pointer pointer to a struct PeerInfo
3149 * @return 0 if equidistant to target,
3150 * -1 if p1 is closer,
3154 compare_peers (const void *p1, const void *p2)
3156 struct PeerInfo **first = (struct PeerInfo **) p1;
3157 struct PeerInfo **second = (struct PeerInfo **) p2;
3159 if ((*first)->matching_bits > (*second)->matching_bits)
3161 if ((*first)->matching_bits < (*second)->matching_bits)
3169 * Select a peer from the routing table that would be a good routing
3170 * destination for sending a message for "target". The resulting peer
3171 * must not be in the set of blocked peers.<p>
3173 * Note that we should not ALWAYS select the closest peer to the
3174 * target, peers further away from the target should be chosen with
3175 * exponentially declining probability.
3177 * @param target the key we are selecting a peer to route to
3178 * @param bloom a bloomfilter containing entries this request has seen already
3179 * @param hops how many hops has this message traversed thus far
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 (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 (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 (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 (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 (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 (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_MAX));
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_MAX);
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_MAX));
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_MAX);
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_MAX));
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_MAX));
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.
4605 * @param cls closure
4606 * @param message message
4607 * @param peer peer identity this notification is about
4608 * @param atsi performance data
4612 handle_dht_p2p_route_request (void *cls,
4613 const struct GNUNET_PeerIdentity *peer,
4614 const struct GNUNET_MessageHeader *message,
4615 const struct GNUNET_TRANSPORT_ATS_Information
4619 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4620 "`%s:%s': Received P2P request from peer %s\n", my_short_id,
4621 "DHT", GNUNET_i2s (peer));
4623 struct GNUNET_DHT_P2PRouteMessage *incoming =
4624 (struct GNUNET_DHT_P2PRouteMessage *) message;
4625 struct GNUNET_MessageHeader *enc_msg =
4626 (struct GNUNET_MessageHeader *) &incoming[1];
4627 struct DHT_MessageContext *msg_ctx;
4629 if (ntohs (enc_msg->type) == GNUNET_MESSAGE_TYPE_DHT_P2P_PING) /* Throw these away. FIXME: Don't throw these away? (reply) */
4632 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4633 "%s:%s Received P2P Ping message.\n", my_short_id, "DHT");
4638 if (ntohs (enc_msg->size) >= GNUNET_SERVER_MAX_MESSAGE_SIZE - 1)
4640 GNUNET_break_op (0);
4644 if (malicious_dropper == GNUNET_YES)
4646 #if DEBUG_DHT_ROUTING
4647 if ((debug_routes_extended) && (dhtlog_handle != NULL))
4649 /** Log routes that die due to high load! */
4650 dhtlog_handle->insert_route (NULL,
4651 GNUNET_ntohll (incoming->unique_id),
4653 ntohl (incoming->hop_count),
4654 GNUNET_SYSERR, &my_identity,
4655 &incoming->key, peer, NULL);
4661 if (get_max_send_delay ().rel_value > MAX_REQUEST_TIME.rel_value)
4663 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4664 "Sending of previous replies took too long, backing off!\n");
4665 increment_stats ("# route requests dropped due to high load");
4666 decrease_max_send_delay (get_max_send_delay ());
4667 #if DEBUG_DHT_ROUTING
4668 if ((debug_routes_extended) && (dhtlog_handle != NULL))
4670 /** Log routes that die due to high load! */
4671 dhtlog_handle->insert_route (NULL,
4672 GNUNET_ntohll (incoming->unique_id),
4674 ntohl (incoming->hop_count),
4675 GNUNET_SYSERR, &my_identity,
4676 &incoming->key, peer, NULL);
4681 msg_ctx = GNUNET_malloc (sizeof (struct DHT_MessageContext));
4683 GNUNET_CONTAINER_bloomfilter_init (incoming->bloomfilter, DHT_BLOOM_SIZE,
4685 GNUNET_assert (msg_ctx->bloom != NULL);
4686 msg_ctx->hop_count = ntohl (incoming->hop_count);
4687 memcpy (&msg_ctx->key, &incoming->key, sizeof (GNUNET_HashCode));
4688 msg_ctx->replication = ntohl (incoming->desired_replication_level);
4689 msg_ctx->unique_id = GNUNET_ntohll (incoming->unique_id);
4690 msg_ctx->msg_options = ntohl (incoming->options);
4691 msg_ctx->network_size = ntohl (incoming->network_size);
4692 msg_ctx->peer = peer;
4693 msg_ctx->importance = DHT_DEFAULT_P2P_IMPORTANCE;
4694 msg_ctx->timeout = DHT_DEFAULT_P2P_TIMEOUT;
4695 demultiplex_message (enc_msg, msg_ctx);
4696 if (msg_ctx->bloom != NULL)
4698 GNUNET_CONTAINER_bloomfilter_free (msg_ctx->bloom);
4699 msg_ctx->bloom = NULL;
4701 GNUNET_free (msg_ctx);
4707 * Core handler for p2p route results.
4709 * @param cls closure
4710 * @param message message
4711 * @param peer peer identity this notification is about
4712 * @param atsi performance data
4716 handle_dht_p2p_route_result (void *cls,
4717 const struct GNUNET_PeerIdentity *peer,
4718 const struct GNUNET_MessageHeader *message,
4719 const struct GNUNET_TRANSPORT_ATS_Information
4723 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4724 "`%s:%s': Received request from peer %s\n", my_short_id, "DHT",
4727 struct GNUNET_DHT_P2PRouteResultMessage *incoming =
4728 (struct GNUNET_DHT_P2PRouteResultMessage *) message;
4729 struct GNUNET_MessageHeader *enc_msg =
4730 (struct GNUNET_MessageHeader *) &incoming[1];
4731 struct DHT_MessageContext msg_ctx;
4733 if (ntohs (enc_msg->size) >= GNUNET_SERVER_MAX_MESSAGE_SIZE - 1)
4735 GNUNET_break_op (0);
4739 if (malicious_dropper == GNUNET_YES)
4741 #if DEBUG_DHT_ROUTING
4742 if ((debug_routes_extended) && (dhtlog_handle != NULL))
4744 /** Log routes that die due to high load! */
4745 dhtlog_handle->insert_route (NULL,
4746 GNUNET_ntohll (incoming->unique_id),
4748 ntohl (incoming->hop_count),
4749 GNUNET_SYSERR, &my_identity,
4750 &incoming->key, peer, NULL);
4756 memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext));
4757 // FIXME: call GNUNET_BLOCK_evaluate (...) -- instead of doing your own bloomfilter!
4759 GNUNET_CONTAINER_bloomfilter_init (incoming->bloomfilter, DHT_BLOOM_SIZE,
4761 GNUNET_assert (msg_ctx.bloom != NULL);
4762 memcpy (&msg_ctx.key, &incoming->key, sizeof (GNUNET_HashCode));
4763 msg_ctx.unique_id = GNUNET_ntohll (incoming->unique_id);
4764 msg_ctx.msg_options = ntohl (incoming->options);
4765 msg_ctx.hop_count = ntohl (incoming->hop_count);
4766 msg_ctx.peer = peer;
4767 msg_ctx.importance = DHT_DEFAULT_P2P_IMPORTANCE + 2; /* Make result routing a higher priority */
4768 msg_ctx.timeout = DHT_DEFAULT_P2P_TIMEOUT;
4769 route_result_message (enc_msg, &msg_ctx);
4775 * Receive the HELLO from transport service,
4776 * free current and replace if necessary.
4779 * @param message HELLO message of peer
4782 process_hello (void *cls, const struct GNUNET_MessageHeader *message)
4785 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4786 "Received our `%s' from transport service\n", "HELLO");
4789 GNUNET_assert (message != NULL);
4790 GNUNET_free_non_null (my_hello);
4791 my_hello = GNUNET_malloc (ntohs (message->size));
4792 memcpy (my_hello, message, ntohs (message->size));
4797 * Task run during shutdown.
4803 shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
4806 struct PeerInfo *pos;
4808 if (transport_handle != NULL)
4810 GNUNET_free_non_null (my_hello);
4811 GNUNET_TRANSPORT_get_hello_cancel (transport_handle, &process_hello,
4813 GNUNET_TRANSPORT_disconnect (transport_handle);
4815 for (bucket_count = lowest_bucket; bucket_count < MAX_BUCKETS;
4818 while (k_buckets[bucket_count].head != NULL)
4820 pos = k_buckets[bucket_count].head;
4822 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4823 "%s:%s Removing peer %s from bucket %d!\n", my_short_id,
4824 "DHT", GNUNET_i2s (&pos->id), bucket_count);
4826 delete_peer (pos, bucket_count);
4829 if (coreAPI != NULL)
4832 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4833 "%s:%s Disconnecting core!\n", my_short_id, "DHT");
4835 GNUNET_CORE_disconnect (coreAPI);
4838 if (datacache != NULL)
4841 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4842 "%s:%s Destroying datacache!\n", my_short_id, "DHT");
4844 GNUNET_DATACACHE_destroy (datacache);
4849 GNUNET_STATISTICS_destroy (stats, GNUNET_YES);
4852 if (dhtlog_handle != NULL)
4854 GNUNET_DHTLOG_disconnect (dhtlog_handle);
4855 dhtlog_handle = NULL;
4857 if (block_context != NULL)
4859 GNUNET_BLOCK_context_destroy (block_context);
4860 block_context = NULL;
4862 GNUNET_free_non_null (my_short_id);
4868 * To be called on core init/fail.
4870 * @param cls service closure
4871 * @param server handle to the server for this service
4872 * @param identity the public identity of this peer
4873 * @param publicKey the public key of this peer
4876 core_init (void *cls,
4877 struct GNUNET_CORE_Handle *server,
4878 const struct GNUNET_PeerIdentity *identity,
4879 const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *publicKey)
4885 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4886 "%s: Connection to core FAILED!\n", "dht",
4887 GNUNET_i2s (identity));
4889 GNUNET_SCHEDULER_cancel (cleanup_task);
4890 GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
4894 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4895 "%s: Core connection initialized, I am peer: %s\n", "dht",
4896 GNUNET_i2s (identity));
4899 /* Copy our identity so we can use it */
4900 memcpy (&my_identity, identity, sizeof (struct GNUNET_PeerIdentity));
4901 if (my_short_id != NULL)
4902 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
4903 "%s Receive CORE INIT message but have already been initialized! Did CORE fail?\n",
4905 my_short_id = GNUNET_strdup (GNUNET_i2s (&my_identity));
4906 /* Set the server to local variable */
4909 if (dhtlog_handle != NULL)
4910 dhtlog_handle->insert_node (NULL, &my_identity);
4914 static struct GNUNET_SERVER_MessageHandler plugin_handlers[] = {
4915 {&handle_dht_local_route_request, NULL, GNUNET_MESSAGE_TYPE_DHT_LOCAL_ROUTE,
4917 {&handle_dht_local_route_stop, NULL,
4918 GNUNET_MESSAGE_TYPE_DHT_LOCAL_ROUTE_STOP, 0},
4919 {&handle_dht_control_message, NULL, GNUNET_MESSAGE_TYPE_DHT_CONTROL, 0},
4924 static struct GNUNET_CORE_MessageHandler core_handlers[] = {
4925 {&handle_dht_p2p_route_request, GNUNET_MESSAGE_TYPE_DHT_P2P_ROUTE, 0},
4926 {&handle_dht_p2p_route_result, GNUNET_MESSAGE_TYPE_DHT_P2P_ROUTE_RESULT, 0},
4932 * Method called whenever a peer connects.
4934 * @param cls closure
4935 * @param peer peer identity this notification is about
4936 * @param atsi performance data
4939 handle_core_connect (void *cls,
4940 const struct GNUNET_PeerIdentity *peer,
4941 const struct GNUNET_TRANSPORT_ATS_Information *atsi)
4943 struct PeerInfo *ret;
4945 /* Check for connect to self message */
4946 if (0 == memcmp(&my_identity, peer, sizeof(struct GNUNET_PeerIdentity)))
4950 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4951 "%s:%s Receives core connect message for peer %s distance %d!\n",
4952 my_short_id, "dht", GNUNET_i2s (peer), distance);
4956 GNUNET_CONTAINER_multihashmap_contains (all_known_peers,
4959 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4960 "%s:%s Received %s message for peer %s, but already have peer in RT!",
4961 my_short_id, "DHT", "CORE CONNECT", GNUNET_i2s (peer));
4965 if (datacache != NULL)
4966 GNUNET_DATACACHE_put (datacache, &peer->hashPubKey,
4967 sizeof (struct GNUNET_PeerIdentity),
4968 (const char *) peer, GNUNET_BLOCK_TYPE_DHT_HELLO,
4969 GNUNET_TIME_absolute_get_forever ());
4970 ret = try_add_peer (peer, find_current_bucket (&peer->hashPubKey), atsi);
4973 newly_found_peers++;
4974 GNUNET_CONTAINER_multihashmap_put (all_known_peers, &peer->hashPubKey,
4976 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY);
4979 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
4980 "%s:%s Adding peer to routing list: %s\n", my_short_id, "DHT",
4981 ret == NULL ? "NOT ADDED" : "PEER ADDED");
4987 * Method called whenever a peer disconnects.
4989 * @param cls closure
4990 * @param peer peer identity this notification is about
4993 handle_core_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer)
4995 struct PeerInfo *to_remove;
4998 /* Check for disconnect from self message */
4999 if (0 == memcmp(&my_identity, peer, sizeof(struct GNUNET_PeerIdentity)))
5002 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
5003 "%s:%s: Received peer disconnect message for peer `%s' from %s\n",
5004 my_short_id, "DHT", GNUNET_i2s (peer), "CORE");
5007 GNUNET_CONTAINER_multihashmap_contains (all_known_peers,
5010 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
5011 "%s:%s: do not have peer `%s' in RT, can't disconnect!\n",
5012 my_short_id, "DHT", GNUNET_i2s (peer));
5015 increment_stats (STAT_DISCONNECTS);
5016 GNUNET_assert (GNUNET_CONTAINER_multihashmap_contains
5017 (all_known_peers, &peer->hashPubKey));
5019 GNUNET_CONTAINER_multihashmap_get (all_known_peers, &peer->hashPubKey);
5020 GNUNET_assert (to_remove != NULL);
5022 memcmp (peer, &to_remove->id,
5023 sizeof (struct GNUNET_PeerIdentity)));
5024 current_bucket = find_current_bucket (&to_remove->id.hashPubKey);
5025 delete_peer (to_remove, current_bucket);
5030 * Process dht requests.
5032 * @param cls closure
5033 * @param server the initialized server
5034 * @param c configuration to use
5038 struct GNUNET_SERVER_Handle *server,
5039 const struct GNUNET_CONFIGURATION_Handle *c)
5041 struct GNUNET_TIME_Relative next_send_time;
5042 unsigned long long temp_config_num;
5043 char *converge_modifier_buf;
5046 datacache = GNUNET_DATACACHE_create (cfg, "dhtcache");
5047 GNUNET_SERVER_add_handlers (server, plugin_handlers);
5048 GNUNET_SERVER_disconnect_notify (server, &handle_client_disconnect, NULL);
5049 coreAPI = GNUNET_CORE_connect (cfg, /* Main configuration */
5050 DEFAULT_CORE_QUEUE_SIZE, /* queue size */
5051 NULL, /* Closure passed to DHT functions */
5052 &core_init, /* Call core_init once connected */
5053 &handle_core_connect, /* Handle connects */
5054 &handle_core_disconnect, /* remove peers on disconnects */
5055 NULL, /* Do we care about "status" updates? */
5056 NULL, /* Don't want notified about all incoming messages */
5057 GNUNET_NO, /* For header only inbound notification */
5058 NULL, /* Don't want notified about all outbound messages */
5059 GNUNET_NO, /* For header only outbound notification */
5060 core_handlers); /* Register these handlers */
5062 if (coreAPI == NULL)
5064 transport_handle = GNUNET_TRANSPORT_connect (cfg,
5065 NULL, NULL, NULL, NULL, NULL);
5066 if (transport_handle != NULL)
5067 GNUNET_TRANSPORT_get_hello (transport_handle, &process_hello, NULL);
5069 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
5070 "Failed to connect to transport service!\n");
5071 block_context = GNUNET_BLOCK_context_create (cfg);
5072 lowest_bucket = MAX_BUCKETS - 1;
5073 forward_list.hashmap =
5074 GNUNET_CONTAINER_multihashmap_create (MAX_OUTSTANDING_FORWARDS / 10);
5075 forward_list.minHeap =
5076 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
5077 all_known_peers = GNUNET_CONTAINER_multihashmap_create (MAX_BUCKETS / 8);
5078 recent_find_peer_requests =
5079 GNUNET_CONTAINER_multihashmap_create (MAX_BUCKETS / 8);
5080 GNUNET_assert (all_known_peers != NULL);
5082 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht_testing",
5085 debug_routes = GNUNET_YES;
5089 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "strict_kademlia"))
5091 strict_kademlia = GNUNET_YES;
5095 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "stop_on_closest"))
5097 stop_on_closest = GNUNET_YES;
5101 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "stop_found"))
5103 stop_on_found = GNUNET_YES;
5107 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "malicious_getter"))
5109 malicious_getter = GNUNET_YES;
5110 if (GNUNET_NO == GNUNET_CONFIGURATION_get_value_number (cfg, "DHT",
5111 "MALICIOUS_GET_FREQUENCY",
5112 &malicious_get_frequency))
5113 malicious_get_frequency = DEFAULT_MALICIOUS_GET_FREQUENCY;
5116 if (GNUNET_YES != GNUNET_CONFIGURATION_get_value_number (cfg, "DHT",
5120 max_hops = DEFAULT_MAX_HOPS;
5123 if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "DHT",
5126 use_max_hops = GNUNET_YES;
5130 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "malicious_putter"))
5132 malicious_putter = GNUNET_YES;
5133 if (GNUNET_NO == GNUNET_CONFIGURATION_get_value_number (cfg, "DHT",
5134 "MALICIOUS_PUT_FREQUENCY",
5135 &malicious_put_frequency))
5136 malicious_put_frequency = DEFAULT_MALICIOUS_PUT_FREQUENCY;
5139 dht_republish_frequency = GNUNET_DHT_DEFAULT_REPUBLISH_FREQUENCY;
5141 GNUNET_CONFIGURATION_get_value_number (cfg, "DHT",
5142 "REPLICATION_FREQUENCY",
5145 dht_republish_frequency =
5146 GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES,
5151 GNUNET_CONFIGURATION_get_value_number (cfg, "DHT", "bucket_size",
5154 bucket_size = (unsigned int) temp_config_num;
5158 GNUNET_CONFIGURATION_get_value_number (cfg, "DHT", "kad_alpha",
5159 &kademlia_replication))
5161 kademlia_replication = DEFAULT_KADEMLIA_REPLICATION;
5165 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "malicious_dropper"))
5167 malicious_dropper = GNUNET_YES;
5171 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "republish"))
5172 do_republish = GNUNET_NO;
5175 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "do_find_peer"))
5177 do_find_peer = GNUNET_NO;
5180 do_find_peer = GNUNET_YES;
5183 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "use_real_distance"))
5184 use_real_distance = GNUNET_YES;
5187 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht_testing",
5188 "mysql_logging_extended"))
5190 debug_routes = GNUNET_YES;
5191 debug_routes_extended = GNUNET_YES;
5194 #if DEBUG_DHT_ROUTING
5195 if (GNUNET_YES == debug_routes)
5197 dhtlog_handle = GNUNET_DHTLOG_connect (cfg);
5198 if (dhtlog_handle == NULL)
5200 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
5201 "Could not connect to mysql logging server, logging will not happen!");
5206 converge_option = DHT_CONVERGE_SQUARE;
5208 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "converge_linear"))
5210 converge_option = DHT_CONVERGE_LINEAR;
5212 else if (GNUNET_YES ==
5213 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht",
5214 "converge_exponential"))
5216 converge_option = DHT_CONVERGE_EXPONENTIAL;
5218 else if (GNUNET_YES ==
5219 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht",
5222 converge_option = DHT_CONVERGE_RANDOM;
5224 else if (GNUNET_YES ==
5225 GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht",
5228 converge_option = DHT_CONVERGE_BINARY;
5232 GNUNET_CONFIGURATION_get_value_string (cfg, "dht", "converge_modifier",
5233 &converge_modifier_buf))
5235 if (1 != sscanf (converge_modifier_buf, "%f", &converge_modifier))
5237 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
5238 "Failed to read decimal value for %s from `%s'\n",
5239 "CONVERGE_MODIFIER", converge_modifier_buf);
5240 converge_modifier = 0.0;
5242 GNUNET_free (converge_modifier_buf);
5245 stats = GNUNET_STATISTICS_create ("dht", cfg);
5249 GNUNET_STATISTICS_set (stats, STAT_ROUTES, 0, GNUNET_NO);
5250 GNUNET_STATISTICS_set (stats, STAT_ROUTE_FORWARDS, 0, GNUNET_NO);
5251 GNUNET_STATISTICS_set (stats, STAT_ROUTE_FORWARDS_CLOSEST, 0,
5253 GNUNET_STATISTICS_set (stats, STAT_RESULTS, 0, GNUNET_NO);
5254 GNUNET_STATISTICS_set (stats, STAT_RESULTS_TO_CLIENT, 0, GNUNET_NO);
5255 GNUNET_STATISTICS_set (stats, STAT_RESULT_FORWARDS, 0, GNUNET_NO);
5256 GNUNET_STATISTICS_set (stats, STAT_GETS, 0, GNUNET_NO);
5257 GNUNET_STATISTICS_set (stats, STAT_PUTS, 0, GNUNET_NO);
5258 GNUNET_STATISTICS_set (stats, STAT_PUTS_INSERTED, 0, GNUNET_NO);
5259 GNUNET_STATISTICS_set (stats, STAT_FIND_PEER, 0, GNUNET_NO);
5260 GNUNET_STATISTICS_set (stats, STAT_FIND_PEER_START, 0, GNUNET_NO);
5261 GNUNET_STATISTICS_set (stats, STAT_GET_START, 0, GNUNET_NO);
5262 GNUNET_STATISTICS_set (stats, STAT_PUT_START, 0, GNUNET_NO);
5263 GNUNET_STATISTICS_set (stats, STAT_FIND_PEER_REPLY, 0, GNUNET_NO);
5264 GNUNET_STATISTICS_set (stats, STAT_FIND_PEER_ANSWER, 0, GNUNET_NO);
5265 GNUNET_STATISTICS_set (stats, STAT_BLOOM_FIND_PEER, 0, GNUNET_NO);
5266 GNUNET_STATISTICS_set (stats, STAT_GET_REPLY, 0, GNUNET_NO);
5267 GNUNET_STATISTICS_set (stats, STAT_GET_RESPONSE_START, 0, GNUNET_NO);
5268 GNUNET_STATISTICS_set (stats, STAT_HELLOS_PROVIDED, 0, GNUNET_NO);
5269 GNUNET_STATISTICS_set (stats, STAT_DISCONNECTS, 0, GNUNET_NO);
5271 /* FIXME: if there are no recent requests then these never get freed, but alternative is _annoying_! */
5272 recent.hashmap = GNUNET_CONTAINER_multihashmap_create (DHT_MAX_RECENT / 2);
5274 GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN);
5275 if (GNUNET_YES == do_find_peer)
5277 next_send_time.rel_value = DHT_MINIMUM_FIND_PEER_INTERVAL.rel_value +
5278 GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_STRONG,
5279 (DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value /
5281 DHT_MINIMUM_FIND_PEER_INTERVAL.rel_value);
5282 find_peer_context.start = GNUNET_TIME_absolute_get ();
5283 GNUNET_SCHEDULER_add_delayed (next_send_time,
5284 &send_find_peer_message,
5285 &find_peer_context);
5288 /* Scheduled the task to clean up when shutdown is called */
5289 cleanup_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
5290 &shutdown_task, NULL);
5294 * The main function for the dht service.
5296 * @param argc number of arguments from the command line
5297 * @param argv command line arguments
5298 * @return 0 ok, 1 on error
5301 main (int argc, char *const *argv)
5306 GNUNET_SERVICE_run (argc,
5309 GNUNET_SERVICE_OPTION_NONE, &run, NULL)) ? 0 : 1;
5310 GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (recent.hashmap));
5311 GNUNET_assert (0 == GNUNET_CONTAINER_heap_get_size (recent.minHeap));
5312 GNUNET_CONTAINER_multihashmap_destroy (recent_find_peer_requests);
5313 GNUNET_CONTAINER_multihashmap_destroy (recent.hashmap);
5314 GNUNET_CONTAINER_heap_destroy (recent.minHeap);