/* This file is part of GNUnet. (C) 2009, 2010 Christian Grothoff (and other contributing authors) GNUnet is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version. GNUnet is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNUnet; see the file COPYING. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /** * @file dht/gnunet-service-dht.c * @brief GNUnet DHT service * @author Christian Grothoff * @author Nathan Evans */ #include "platform.h" #include "gnunet_block_lib.h" #include "gnunet_client_lib.h" #include "gnunet_getopt_lib.h" #include "gnunet_os_lib.h" #include "gnunet_protocols.h" #include "gnunet_service_lib.h" #include "gnunet_core_service.h" #include "gnunet_signal_lib.h" #include "gnunet_util_lib.h" #include "gnunet_datacache_lib.h" #include "gnunet_transport_service.h" #include "gnunet_hello_lib.h" #include "gnunet_dht_service.h" #include "gnunet_statistics_service.h" #include "dhtlog.h" #include "dht.h" #include #define PRINT_TABLES GNUNET_NO #define REAL_DISTANCE GNUNET_NO #define EXTRA_CHECKS GNUNET_NO /** * How many buckets will we allow total. */ #define MAX_BUCKETS sizeof (GNUNET_HashCode) * 8 /** * Should the DHT issue FIND_PEER requests to get better routing tables? */ #define DEFAULT_DO_FIND_PEER GNUNET_YES /** * Defines whether find peer requests send their HELLO's outgoing, * or expect replies to contain hellos. */ #define FIND_PEER_WITH_HELLO GNUNET_YES /** * What is the maximum number of peers in a given bucket. */ #define DEFAULT_BUCKET_SIZE 4 #define DEFAULT_CORE_QUEUE_SIZE 32 /** * Minimum number of peers we need for "good" routing, * any less than this and we will allow messages to * travel much further through the network! */ #define MINIMUM_PEER_THRESHOLD 20 #define DHT_MAX_RECENT 1000 #define FIND_PEER_CALC_INTERVAL GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 60) /** * Default time to wait to send messages on behalf of other peers. */ #define DHT_DEFAULT_P2P_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 10) /** * Default importance for handling messages on behalf of other peers. */ #define DHT_DEFAULT_P2P_IMPORTANCE 0 /** * How long to keep recent requests around by default. */ #define DEFAULT_RECENT_REMOVAL GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 15) /** * Default time to wait to send find peer messages sent by the dht service. */ #define DHT_DEFAULT_FIND_PEER_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30) /** * Default importance for find peer messages sent by the dht service. */ #define DHT_DEFAULT_FIND_PEER_IMPORTANCE 8 /** * Default replication parameter for find peer messages sent by the dht service. */ #define DHT_DEFAULT_FIND_PEER_REPLICATION 4 /** * Default options for find peer requests sent by the dht service. */ #define DHT_DEFAULT_FIND_PEER_OPTIONS GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE /*#define DHT_DEFAULT_FIND_PEER_OPTIONS GNUNET_DHT_RO_NONE*/ /** * How long at least to wait before sending another find peer request. */ #define DHT_MINIMUM_FIND_PEER_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 2) /** * How long at most to wait before sending another find peer request. */ #define DHT_MAXIMUM_FIND_PEER_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 8) /** * How often to update our preference levels for peers in our routing tables. */ #define DHT_DEFAULT_PREFERENCE_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 2) /** * How long at most on average will we allow a reply forward to take * (before we quit sending out new requests) */ #define MAX_REQUEST_TIME GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1) /** * How many initial requests to send out (in true Kademlia fashion) */ #define DEFAULT_KADEMLIA_REPLICATION 3 /* * Default frequency for sending malicious get messages */ #define DEFAULT_MALICIOUS_GET_FREQUENCY 1000 /* Number of milliseconds */ /* * Default frequency for sending malicious put messages */ #define DEFAULT_MALICIOUS_PUT_FREQUENCY 1000 /* Default is in milliseconds */ #define DHT_DEFAULT_PING_DELAY GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 1) /** * Real maximum number of hops, at which point we refuse * to forward the message. */ #define DEFAULT_MAX_HOPS 10 /** * How many time differences between requesting a core send and * the actual callback to remember. */ #define MAX_REPLY_TIMES 8 enum ConvergenceOptions { /** * Use the linear method for convergence. */ DHT_CONVERGE_LINEAR, /** * Converge using a fast converging square * function. */ DHT_CONVERGE_SQUARE, /** * Converge using a slower exponential * function. */ DHT_CONVERGE_EXPONENTIAL, /** * Don't do any special convergence, allow * the algorithm to hopefully route to closer * peers more often. */ DHT_CONVERGE_RANDOM, /** * Binary convergence, start routing to closest * only after set number of hops. */ DHT_CONVERGE_BINARY }; /** * Linked list of messages to send to clients. */ struct P2PPendingMessage { /** * Pointer to next item in the list */ struct P2PPendingMessage *next; /** * Pointer to previous item in the list */ struct P2PPendingMessage *prev; /** * Message importance level. */ unsigned int importance; /** * Time when this request was scheduled to be sent. */ struct GNUNET_TIME_Absolute scheduled; /** * How long to wait before sending message. */ struct GNUNET_TIME_Relative timeout; /** * Actual message to be sent; // avoid allocation */ const struct GNUNET_MessageHeader *msg; // msg = (cast) &pm[1]; // memcpy (&pm[1], data, len); }; /** * Per-peer information. */ struct PeerInfo { /** * Next peer entry (DLL) */ struct PeerInfo *next; /** * Prev peer entry (DLL) */ struct PeerInfo *prev; /** * Count of outstanding messages for peer. */ unsigned int pending_count; /** * Head of pending messages to be sent to this peer. */ struct P2PPendingMessage *head; /** * Tail of pending messages to be sent to this peer. */ struct P2PPendingMessage *tail; /** * Core handle for sending messages to this peer. */ struct GNUNET_CORE_TransmitHandle *th; /** * Task for scheduling message sends. */ GNUNET_SCHEDULER_TaskIdentifier send_task; /** * Task for scheduling preference updates */ GNUNET_SCHEDULER_TaskIdentifier preference_task; /** * Preference update context */ struct GNUNET_CORE_InformationRequestContext *info_ctx; /** * What is the identity of the peer? */ struct GNUNET_PeerIdentity id; #if 0 /** * What is the average latency for replies received? */ struct GNUNET_TIME_Relative latency; /** * Transport level distance to peer. */ unsigned int distance; #endif /** * Holds matching bits from peer to current target, * used for distance comparisons between peers. May * be considered a really bad idea. * FIXME: remove this value (create struct which holds * a single peerinfo and the matching bits, use * that to pass to comparator) */ unsigned int matching_bits; /** * Task for scheduling periodic ping messages for this peer. */ GNUNET_SCHEDULER_TaskIdentifier ping_task; }; /** * Peers are grouped into buckets. */ struct PeerBucket { /** * Head of DLL */ struct PeerInfo *head; /** * Tail of DLL */ struct PeerInfo *tail; /** * Number of peers in the bucket. */ unsigned int peers_size; }; /** * Linked list of messages to send to clients. */ struct PendingMessage { /** * Pointer to next item in the list */ struct PendingMessage *next; /** * Pointer to previous item in the list */ struct PendingMessage *prev; /** * Actual message to be sent; // avoid allocation */ const struct GNUNET_MessageHeader *msg; // msg = (cast) &pm[1]; // memcpy (&pm[1], data, len); }; /** * Struct containing information about a client, * handle to connect to it, and any pending messages * that need to be sent to it. */ struct ClientList { /** * Linked list of active clients */ struct ClientList *next; /** * The handle to this client */ struct GNUNET_SERVER_Client *client_handle; /** * Handle to the current transmission request, NULL * if none pending. */ struct GNUNET_CONNECTION_TransmitHandle *transmit_handle; /** * Linked list of pending messages for this client */ struct PendingMessage *pending_head; /** * Tail of linked list of pending messages for this client */ struct PendingMessage *pending_tail; }; /** * Context containing information about a DHT message received. */ struct DHT_MessageContext { /** * The client this request was received from. * (NULL if received from another peer) */ struct ClientList *client; /** * The peer this request was received from. * (NULL if received from local client) */ const struct GNUNET_PeerIdentity *peer; /** * Bloomfilter for this routing request. */ struct GNUNET_CONTAINER_BloomFilter *bloom; /** * extended query (see gnunet_block_lib.h). */ const void *xquery; /** * Bloomfilter to filter out duplicate replies. */ struct GNUNET_CONTAINER_BloomFilter *reply_bf; /** * The key this request was about */ GNUNET_HashCode key; /** * How long should we wait to transmit this request? */ struct GNUNET_TIME_Relative timeout; /** * The unique identifier of this request */ uint64_t unique_id; /** * Number of bytes in xquery. */ size_t xquery_size; /** * Mutator value for the reply_bf, see gnunet_block_lib.h */ uint32_t reply_bf_mutator; /** * Desired replication level */ uint32_t replication; /** * Network size estimate, either ours or the sum of * those routed to thus far. =~ Log of number of peers * chosen from for this request. */ uint32_t network_size; /** * Any message options for this request */ uint32_t msg_options; /** * How many hops has the message already traversed? */ uint32_t hop_count; /** * How many peer identities are present in the path history? */ uint32_t path_history_len; /** * Path history. */ char *path_history; /** * How important is this message? */ unsigned int importance; /** * Should we (still) forward the request on to other peers? */ int do_forward; /** * Did we forward this message? (may need to remember it!) */ int forwarded; /** * Are we the closest known peer to this key (out of our neighbors?) */ int closest; }; /** * Record used for remembering what peers are waiting for what * responses (based on search key). */ struct DHTRouteSource { /** * This is a DLL. */ struct DHTRouteSource *next; /** * This is a DLL. */ struct DHTRouteSource *prev; /** * Source of the request. Replies should be forwarded to * this peer. */ struct GNUNET_PeerIdentity source; /** * If this was a local request, remember the client; otherwise NULL. */ struct ClientList *client; /** * Pointer to this nodes heap location (for removal) */ struct GNUNET_CONTAINER_HeapNode *hnode; /** * Back pointer to the record storing this information. */ struct DHTQueryRecord *record; /** * Task to remove this entry on timeout. */ GNUNET_SCHEDULER_TaskIdentifier delete_task; /** * Bloomfilter of peers we have already sent back as * replies to the initial request. Allows us to not * forward the same peer multiple times for a find peer * request. */ struct GNUNET_CONTAINER_BloomFilter *find_peers_responded; }; /** * Entry in the DHT routing table. */ struct DHTQueryRecord { /** * Head of DLL for result forwarding. */ struct DHTRouteSource *head; /** * Tail of DLL for result forwarding. */ struct DHTRouteSource *tail; /** * Key that the record concerns. */ GNUNET_HashCode key; /** * GET message of this record (what we already forwarded?). */ //DV_DHT_MESSAGE get; Try to get away with not saving this. /** * Bloomfilter of the peers we've replied to so far */ //struct GNUNET_BloomFilter *bloom_results; Don't think we need this, just remove from DLL on response. }; /** * Context used to calculate the number of find peer messages * per X time units since our last scheduled find peer message * was sent. If we have seen too many messages, delay or don't * send our own out. */ struct FindPeerMessageContext { unsigned int count; struct GNUNET_TIME_Absolute start; struct GNUNET_TIME_Absolute end; }; /** * DHT Routing results structure */ struct DHTResults { /* * Min heap for removal upon reaching limit */ struct GNUNET_CONTAINER_Heap *minHeap; /* * Hashmap for fast key based lookup */ struct GNUNET_CONTAINER_MultiHashMap *hashmap; }; /** * DHT structure for recent requests. */ struct RecentRequests { /* * Min heap for removal upon reaching limit */ struct GNUNET_CONTAINER_Heap *minHeap; /* * Hashmap for key based lookup */ struct GNUNET_CONTAINER_MultiHashMap *hashmap; }; struct RecentRequest { /** * Position of this node in the min heap. */ struct GNUNET_CONTAINER_HeapNode *heap_node; /** * Bloomfilter containing entries for peers * we forwarded this request to. */ struct GNUNET_CONTAINER_BloomFilter *bloom; /** * Timestamp of this request, for ordering * the min heap. */ struct GNUNET_TIME_Absolute timestamp; /** * Key of this request. */ GNUNET_HashCode key; /** * Unique identifier for this request. */ uint64_t uid; /** * Task to remove this entry on timeout. */ GNUNET_SCHEDULER_TaskIdentifier remove_task; }; struct RepublishContext { /** * Key to republish. */ GNUNET_HashCode key; /** * Type of the data. */ unsigned int type; }; /** * Which kind of convergence will we be using? */ static enum ConvergenceOptions converge_option; /** * Modifier for the convergence function */ static float converge_modifier; /** * Recent requests by hash/uid and by time inserted. */ static struct RecentRequests recent; /** * Context to use to calculate find peer rates. */ static struct FindPeerMessageContext find_peer_context; /** * Don't use our routing algorithm, always route * to closest peer; initially send requests to 3 * peers. */ static unsigned int strict_kademlia; /** * Routing option to end routing when closest peer found. */ static unsigned int stop_on_closest; /** * Routing option to end routing when data is found. */ static unsigned int stop_on_found; /** * Whether DHT needs to manage find peer requests, or * an external force will do it on behalf of the DHT. */ static unsigned int do_find_peer; /** * Once we have stored an item in the DHT, refresh it * according to our republish interval. */ static unsigned int do_republish; /** * Use exactly the forwarding formula as described in * the paper if set to GNUNET_YES, otherwise use the * slightly modified version. */ static unsigned int paper_forwarding; /** * PUT Peer Identities of peers we know about into * the datacache. */ static unsigned int put_peer_identities; /** * Use the "real" distance metric when selecting the * next routing hop. Can be less accurate. */ static unsigned int use_real_distance; /** * How many peers have we added since we sent out our last * find peer request? */ static unsigned int newly_found_peers; /** * Container of active queries we should remember */ static struct DHTResults forward_list; /** * Handle to the datacache service (for inserting/retrieving data) */ static struct GNUNET_DATACACHE_Handle *datacache; /** * Handle for the statistics service. */ struct GNUNET_STATISTICS_Handle *stats; /** * The configuration the DHT service is running with */ static const struct GNUNET_CONFIGURATION_Handle *cfg; /** * Handle to the core service */ static struct GNUNET_CORE_Handle *coreAPI; /** * Handle to the transport service, for getting our hello */ static struct GNUNET_TRANSPORT_Handle *transport_handle; /** * The identity of our peer. */ static struct GNUNET_PeerIdentity my_identity; /** * Short id of the peer, for printing */ static char *my_short_id; /** * Our HELLO */ static struct GNUNET_MessageHeader *my_hello; /** * Task to run when we shut down, cleaning up all our trash */ static GNUNET_SCHEDULER_TaskIdentifier cleanup_task; /** * The lowest currently used bucket. */ static unsigned int lowest_bucket; /* Initially equal to MAX_BUCKETS - 1 */ /** * The maximum number of hops before we stop routing messages. */ static unsigned long long max_hops; /** * How often to republish content we have previously stored. */ static struct GNUNET_TIME_Relative dht_republish_frequency; /** * GNUNET_YES to stop at max_hops, GNUNET_NO to heuristically decide when to stop forwarding. */ static int use_max_hops; /** * The buckets (Kademlia routing table, complete with growth). * Array of size MAX_BUCKET_SIZE. */ static struct PeerBucket k_buckets[MAX_BUCKETS]; /* From 0 to MAX_BUCKETS - 1 */ /** * Hash map of all known peers, for easy removal from k_buckets on disconnect. */ static struct GNUNET_CONTAINER_MultiHashMap *all_known_peers; /** * Recently seen find peer requests. */ static struct GNUNET_CONTAINER_MultiHashMap *recent_find_peer_requests; /** * Maximum size for each bucket. */ static unsigned int bucket_size = DEFAULT_BUCKET_SIZE; /* Initially equal to DEFAULT_BUCKET_SIZE */ /** * List of active clients. */ static struct ClientList *client_list; /** * Handle to the DHT logger. */ static struct GNUNET_DHTLOG_Handle *dhtlog_handle; /* * Whether or not to send routing debugging information * to the dht logging server */ static unsigned int debug_routes; /* * Whether or not to send FULL route information to * logging server */ static unsigned int debug_routes_extended; /* * GNUNET_YES or GNUNET_NO, whether or not to act as * a malicious node which drops all messages */ static unsigned int malicious_dropper; /* * GNUNET_YES or GNUNET_NO, whether or not to act as * a malicious node which sends out lots of GETS */ static unsigned int malicious_getter; /** * GNUNET_YES or GNUNET_NO, whether or not to act as * a malicious node which sends out lots of PUTS */ static unsigned int malicious_putter; /** * Frequency for malicious get requests. */ static unsigned long long malicious_get_frequency; /** * Frequency for malicious put requests. */ static unsigned long long malicious_put_frequency; /** * Kademlia replication */ static unsigned long long kademlia_replication; /** * Reply times for requests, if we are busy, don't send any * more requests! */ static struct GNUNET_TIME_Relative reply_times[MAX_REPLY_TIMES]; /** * Current counter for replies. */ static unsigned int reply_counter; /** * Our handle to the BLOCK library. */ static struct GNUNET_BLOCK_Context *block_context; /** * Forward declaration. */ static size_t send_generic_reply (void *cls, size_t size, void *buf); /** Declare here so retry_core_send is aware of it */ static size_t core_transmit_notify (void *cls, size_t size, void *buf); /** * Convert unique ID to hash code. * * @param uid unique ID to convert * @param hash set to uid (extended with zeros) */ static void hash_from_uid (uint64_t uid, GNUNET_HashCode * hash) { memset (hash, 0, sizeof (GNUNET_HashCode)); *((uint64_t *) hash) = uid; } #if AVG /** * Calculate the average send time between messages so that we can * ignore certain requests if we get too busy. * * @return the average time between asking core to send a message * and when the buffer for copying it is passed */ static struct GNUNET_TIME_Relative get_average_send_delay () { unsigned int i; unsigned int divisor; struct GNUNET_TIME_Relative average_time; average_time = GNUNET_TIME_relative_get_zero (); divisor = 0; for (i = 0; i < MAX_REPLY_TIMES; i++) { average_time = GNUNET_TIME_relative_add (average_time, reply_times[i]); if (reply_times[i].abs_value == (uint64_t) 0) continue; else divisor++; } if (divisor == 0) { return average_time; } average_time = GNUNET_TIME_relative_divide (average_time, divisor); fprintf (stderr, "Avg send delay: %u sends is %llu\n", divisor, (unsigned long long) average_time.abs_value); return average_time; } #endif /** * Given the largest send delay, artificially decrease it * so the next time around we may have a chance at sending * again. */ static void decrease_max_send_delay (struct GNUNET_TIME_Relative max_time) { unsigned int i; for (i = 0; i < MAX_REPLY_TIMES; i++) { if (reply_times[i].rel_value == max_time.rel_value) { reply_times[i].rel_value = reply_times[i].rel_value / 2; return; } } } /** * Find the maximum send time of the recently sent values. * * @return the average time between asking core to send a message * and when the buffer for copying it is passed */ static struct GNUNET_TIME_Relative get_max_send_delay () { unsigned int i; struct GNUNET_TIME_Relative max_time; max_time = GNUNET_TIME_relative_get_zero (); for (i = 0; i < MAX_REPLY_TIMES; i++) { if (reply_times[i].rel_value > max_time.rel_value) max_time.rel_value = reply_times[i].rel_value; } #if DEBUG_DHT if (max_time.rel_value > MAX_REQUEST_TIME.rel_value) GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Max send delay was %llu\n", (unsigned long long) max_time.rel_value); #endif return max_time; } static void increment_stats (const char *value) { if (stats != NULL) { GNUNET_STATISTICS_update (stats, value, 1, GNUNET_NO); } } /** * Try to send another message from our core send list */ static void try_core_send (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct PeerInfo *peer = cls; struct P2PPendingMessage *pending; size_t ssize; peer->send_task = GNUNET_SCHEDULER_NO_TASK; if ( (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0) return; if (peer->th != NULL) return; /* Message send already in progress */ pending = peer->head; if (pending != NULL) { ssize = ntohs (pending->msg->size); #if DEBUG_DHT > 1 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Calling notify_transmit_ready with size %d for peer %s\n", my_short_id, "DHT", ssize, GNUNET_i2s (&peer->id)); #endif pending->scheduled = GNUNET_TIME_absolute_get (); reply_counter++; if (reply_counter >= MAX_REPLY_TIMES) reply_counter = 0; peer->th = GNUNET_CORE_notify_transmit_ready (coreAPI, GNUNET_YES, pending->importance, pending->timeout, &peer->id, ssize, &core_transmit_notify, peer); if (peer->th == NULL) increment_stats ("# notify transmit ready failed"); } } /** * Function called to send a request out to another peer. * Called both for locally initiated requests and those * received from other peers. * * @param msg the encapsulated message * @param peer the peer to forward the message to * @param msg_ctx the context of the message (hop count, bloom, etc.) */ static void forward_result_message (const struct GNUNET_MessageHeader *msg, struct PeerInfo *peer, struct DHT_MessageContext *msg_ctx) { struct GNUNET_DHT_P2PRouteResultMessage *result_message; struct P2PPendingMessage *pending; size_t msize; size_t psize; char *path_start; char *path_offset; #if DEBUG_PATH unsigned int i; #endif increment_stats (STAT_RESULT_FORWARDS); msize = sizeof (struct GNUNET_DHT_P2PRouteResultMessage) + ntohs (msg->size) + (sizeof(struct GNUNET_PeerIdentity) * msg_ctx->path_history_len); GNUNET_assert (msize <= GNUNET_SERVER_MAX_MESSAGE_SIZE); psize = sizeof (struct P2PPendingMessage) + msize; pending = GNUNET_malloc (psize); pending->msg = (struct GNUNET_MessageHeader *) &pending[1]; pending->importance = DHT_SEND_PRIORITY; pending->timeout = GNUNET_TIME_relative_get_forever (); result_message = (struct GNUNET_DHT_P2PRouteResultMessage *) pending->msg; result_message->header.size = htons (msize); result_message->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_ROUTE_RESULT); result_message->outgoing_path_length = htonl (msg_ctx->path_history_len); if (msg_ctx->path_history_len > 0) { /* End of pending is where enc_msg starts */ path_start = (char *)&pending[1]; /* Offset by the size of the enc_msg */ path_start += ntohs (msg->size); memcpy(path_start, msg_ctx->path_history, msg_ctx->path_history_len * (sizeof(struct GNUNET_PeerIdentity))); #if DEBUG_PATH for (i = 0; i < msg_ctx->path_history_len; i++) { path_offset = &msg_ctx->path_history[i * sizeof(struct GNUNET_PeerIdentity)]; GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "(forward_result) Key %s Found peer %d:%s\n", GNUNET_h2s(&msg_ctx->key), i, GNUNET_i2s((struct GNUNET_PeerIdentity *)path_offset)); } #endif } result_message->options = htonl (msg_ctx->msg_options); result_message->hop_count = htonl (msg_ctx->hop_count + 1); GNUNET_assert (GNUNET_OK == GNUNET_CONTAINER_bloomfilter_get_raw_data (msg_ctx->bloom, result_message-> bloomfilter, DHT_BLOOM_SIZE)); result_message->unique_id = GNUNET_htonll (msg_ctx->unique_id); memcpy (&result_message->key, &msg_ctx->key, sizeof (GNUNET_HashCode)); /* Copy the enc_msg, then the path history as well! */ memcpy (&result_message[1], msg, ntohs (msg->size)); path_offset = (char *)&result_message[1]; path_offset += ntohs (msg->size); /* If we have path history, copy it to the end of the whole thing */ if (msg_ctx->path_history_len > 0) memcpy(path_offset, msg_ctx->path_history, msg_ctx->path_history_len * (sizeof(struct GNUNET_PeerIdentity))); #if DEBUG_DHT > 1 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Adding pending message size %d for peer %s\n", my_short_id, "DHT", msize, GNUNET_i2s (&peer->id)); #endif peer->pending_count++; increment_stats ("# pending messages scheduled"); GNUNET_CONTAINER_DLL_insert_after (peer->head, peer->tail, peer->tail, pending); if (peer->send_task == GNUNET_SCHEDULER_NO_TASK) peer->send_task = GNUNET_SCHEDULER_add_now (&try_core_send, peer); } /** * Called when core is ready to send a message we asked for * out to the destination. * * @param cls closure (NULL) * @param size number of bytes available in buf * @param buf where the callee should write the message * @return number of bytes written to buf */ static size_t core_transmit_notify (void *cls, size_t size, void *buf) { struct PeerInfo *peer = cls; char *cbuf = buf; struct P2PPendingMessage *pending; size_t off; size_t msize; peer->th = NULL; if (buf == NULL) { /* client disconnected */ #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': buffer was NULL\n", my_short_id, "DHT"); #endif return 0; } if (peer->head == NULL) return 0; off = 0; pending = peer->head; #if DUMB reply_times[reply_counter] = GNUNET_TIME_absolute_get_difference (pending->scheduled, GNUNET_TIME_absolute_get ()); msize = ntohs (pending->msg->size); if (msize <= size) { off = msize; memcpy (cbuf, pending->msg, msize); peer->pending_count--; increment_stats ("# pending messages sent"); GNUNET_assert (peer->pending_count >= 0); GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, pending); GNUNET_free (pending); } #else while (NULL != pending && (size - off >= (msize = ntohs (pending->msg->size)))) { memcpy (&cbuf[off], pending->msg, msize); off += msize; peer->pending_count--; increment_stats ("# pending messages sent"); GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, pending); GNUNET_free (pending); pending = peer->head; } #endif if ((peer->head != NULL) && (peer->send_task == GNUNET_SCHEDULER_NO_TASK)) peer->send_task = GNUNET_SCHEDULER_add_now (&try_core_send, peer); return off; } /** * Compute the distance between have and target as a 32-bit value. * Differences in the lower bits must count stronger than differences * in the higher bits. * * @return 0 if have==target, otherwise a number * that is larger as the distance between * the two hash codes increases */ static unsigned int distance (const GNUNET_HashCode * target, const GNUNET_HashCode * have) { unsigned int bucket; unsigned int msb; unsigned int lsb; unsigned int i; /* We have to represent the distance between two 2^9 (=512)-bit numbers as a 2^5 (=32)-bit number with "0" being used for the two numbers being identical; furthermore, we need to guarantee that a difference in the number of matching bits is always represented in the result. We use 2^32/2^9 numerical values to distinguish between hash codes that have the same LSB bit distance and use the highest 2^9 bits of the result to signify the number of (mis)matching LSB bits; if we have 0 matching and hence 512 mismatching LSB bits we return -1 (since 512 itself cannot be represented with 9 bits) */ /* first, calculate the most significant 9 bits of our result, aka the number of LSBs */ bucket = GNUNET_CRYPTO_hash_matching_bits (target, have); /* bucket is now a value between 0 and 512 */ if (bucket == 512) return 0; /* perfect match */ if (bucket == 0) return (unsigned int) -1; /* LSB differs; use max (if we did the bit-shifting below, we'd end up with max+1 (overflow)) */ /* calculate the most significant bits of the final result */ msb = (512 - bucket) << (32 - 9); /* calculate the 32-9 least significant bits of the final result by looking at the differences in the 32-9 bits following the mismatching bit at 'bucket' */ lsb = 0; for (i = bucket + 1; (i < sizeof (GNUNET_HashCode) * 8) && (i < bucket + 1 + 32 - 9); i++) { if (GNUNET_CRYPTO_hash_get_bit (target, i) != GNUNET_CRYPTO_hash_get_bit (have, i)) lsb |= (1 << (bucket + 32 - 9 - i)); /* first bit set will be 10, last bit set will be 31 -- if i does not reach 512 first... */ } return msb | lsb; } /** * Return a number that is larger the closer the * "have" GNUNET_hash code is to the "target". * * @return inverse distance metric, non-zero. * Must fudge the value if NO bits match. */ static unsigned int inverse_distance (const GNUNET_HashCode * target, const GNUNET_HashCode * have) { if (GNUNET_CRYPTO_hash_matching_bits (target, have) == 0) return 1; /* Never return 0! */ return ((unsigned int) -1) - distance (target, have); } /** * Find the optimal bucket for this key, regardless * of the current number of buckets in use. * * @param hc the hashcode to compare our identity to * * @return the proper bucket index, or GNUNET_SYSERR * on error (same hashcode) */ static int find_bucket (const GNUNET_HashCode * hc) { unsigned int bits; bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, hc); if (bits == MAX_BUCKETS) return GNUNET_SYSERR; return MAX_BUCKETS - bits - 1; } /** * Find which k-bucket this peer should go into, * taking into account the size of the k-bucket * array. This means that if more bits match than * there are currently buckets, lowest_bucket will * be returned. * * @param hc GNUNET_HashCode we are finding the bucket for. * * @return the proper bucket index for this key, * or GNUNET_SYSERR on error (same hashcode) */ static int find_current_bucket (const GNUNET_HashCode * hc) { int actual_bucket; actual_bucket = find_bucket (hc); if (actual_bucket == GNUNET_SYSERR) /* hc and our peer identity match! */ return lowest_bucket; else if (actual_bucket < lowest_bucket) /* actual_bucket not yet used */ return lowest_bucket; else return actual_bucket; } #if EXTRA_CHECKS /** * Find a routing table entry from a peer identity * * @param peer the peer to look up * * @return the bucket number holding the peer, GNUNET_SYSERR if not found */ static int find_bucket_by_peer (const struct PeerInfo *peer) { int bucket; struct PeerInfo *pos; for (bucket = lowest_bucket; bucket < MAX_BUCKETS - 1; bucket++) { pos = k_buckets[bucket].head; while (pos != NULL) { if (peer == pos) return bucket; pos = pos->next; } } return GNUNET_SYSERR; /* No such peer. */ } #endif #if PRINT_TABLES /** * Print the complete routing table for this peer. */ static void print_routing_table () { int bucket; struct PeerInfo *pos; char char_buf[30000]; int char_pos; memset (char_buf, 0, sizeof (char_buf)); char_pos = 0; char_pos += sprintf (&char_buf[char_pos], "Printing routing table for peer %s\n", my_short_id); //fprintf(stderr, "Printing routing table for peer %s\n", my_short_id); for (bucket = lowest_bucket; bucket < MAX_BUCKETS; bucket++) { pos = k_buckets[bucket].head; char_pos += sprintf (&char_buf[char_pos], "Bucket %d:\n", bucket); //fprintf(stderr, "Bucket %d:\n", bucket); while (pos != NULL) { //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)); char_pos += sprintf (&char_buf[char_pos], "\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)); pos = pos->next; } } fprintf (stderr, "%s", char_buf); fflush (stderr); } #endif /** * Find a routing table entry from a peer identity * * @param peer the peer identity to look up * * @return the routing table entry, or NULL if not found */ static struct PeerInfo * find_peer_by_id (const struct GNUNET_PeerIdentity *peer) { int bucket; struct PeerInfo *pos; bucket = find_current_bucket (&peer->hashPubKey); if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity))) return NULL; pos = k_buckets[bucket].head; while (pos != NULL) { if (0 == memcmp (&pos->id, peer, sizeof (struct GNUNET_PeerIdentity))) return pos; pos = pos->next; } return NULL; /* No such peer. */ } /* Forward declaration */ static void update_core_preference (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc); /** * Function called with statistics about the given peer. * * @param cls closure * @param peer identifies the peer * @param bpm_out set to the current bandwidth limit (sending) for this peer * @param amount set to the amount that was actually reserved or unreserved; * either the full requested amount or zero (no partial reservations) * @param res_delay if the reservation could not be satisfied (amount was 0), how * long should the client wait until re-trying? * @param preference current traffic preference for the given peer */ static void update_core_preference_finish (void *cls, const struct GNUNET_PeerIdentity *peer, struct GNUNET_BANDWIDTH_Value32NBO bpm_out, int32_t amount, struct GNUNET_TIME_Relative res_delay, uint64_t preference) { struct PeerInfo *peer_info = cls; peer_info->info_ctx = NULL; GNUNET_SCHEDULER_add_delayed (DHT_DEFAULT_PREFERENCE_INTERVAL, &update_core_preference, peer_info); } static void update_core_preference (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct PeerInfo *peer = cls; uint64_t preference; unsigned int matching; if ( (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0) { return; } matching = GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, &peer->id.hashPubKey); if (matching >= 64) { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Peer identifier matches by %u bits, only shifting as much as we can!\n", matching); #endif matching = 63; } preference = 1LL << matching; peer->info_ctx = GNUNET_CORE_peer_change_preference (coreAPI, &peer->id, GNUNET_TIME_relative_get_forever (), GNUNET_BANDWIDTH_value_init (UINT32_MAX), 0, preference, &update_core_preference_finish, peer); } /** * Really add a peer to a bucket (only do assertions * on size, etc.) * * @param peer GNUNET_PeerIdentity of the peer to add * @param bucket the already figured out bucket to add * the peer to * @param atsi performance information * * @return the newly added PeerInfo */ static struct PeerInfo * add_peer (const struct GNUNET_PeerIdentity *peer, unsigned int bucket, const struct GNUNET_TRANSPORT_ATS_Information *atsi) { struct PeerInfo *new_peer; GNUNET_assert (bucket < MAX_BUCKETS); GNUNET_assert (peer != NULL); new_peer = GNUNET_malloc (sizeof (struct PeerInfo)); #if 0 new_peer->latency = latency; new_peer->distance = distance; #endif memcpy (&new_peer->id, peer, sizeof (struct GNUNET_PeerIdentity)); GNUNET_CONTAINER_DLL_insert_after (k_buckets[bucket].head, k_buckets[bucket].tail, k_buckets[bucket].tail, new_peer); k_buckets[bucket].peers_size++; #if DO_UPDATE_PREFERENCE if ((GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, &peer->hashPubKey) > 0) && (k_buckets[bucket].peers_size <= bucket_size)) { new_peer->preference_task = GNUNET_SCHEDULER_add_now (&update_core_preference, new_peer); } #endif return new_peer; } /** * Given a peer and its corresponding bucket, * remove it from that bucket. Does not free * the PeerInfo struct, nor cancel messages * or free messages waiting to be sent to this * peer! * * @param peer the peer to remove * @param bucket the bucket the peer belongs to */ static void remove_peer (struct PeerInfo *peer, unsigned int bucket) { GNUNET_assert (k_buckets[bucket].peers_size > 0); GNUNET_CONTAINER_DLL_remove (k_buckets[bucket].head, k_buckets[bucket].tail, peer); k_buckets[bucket].peers_size--; #if CHANGE_LOWEST if ((bucket == lowest_bucket) && (k_buckets[lowest_bucket].peers_size == 0) && (lowest_bucket < MAX_BUCKETS - 1)) lowest_bucket++; #endif } /** * Removes peer from a bucket, then frees associated * resources and frees peer. * * @param peer peer to be removed and freed * @param bucket which bucket this peer belongs to */ static void delete_peer (struct PeerInfo *peer, unsigned int bucket) { struct P2PPendingMessage *pos; struct P2PPendingMessage *next; #if EXTRA_CHECKS struct PeerInfo *peer_pos; peer_pos = k_buckets[bucket].head; while ((peer_pos != NULL) && (peer_pos != peer)) peer_pos = peer_pos->next; if (peer_pos == NULL) { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "%s:%s: Expected peer `%s' in bucket %d\n", my_short_id, "DHT", GNUNET_i2s (&peer->id), bucket); GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "%s:%s: Lowest bucket: %d, find_current_bucket: %d, peer resides in bucket: %d\n", my_short_id, "DHT", lowest_bucket, find_current_bucket (&peer->id.hashPubKey), find_bucket_by_peer (peer)); } GNUNET_assert (peer_pos != NULL); #endif remove_peer (peer, bucket); /* First remove the peer from its bucket */ if (peer->send_task != GNUNET_SCHEDULER_NO_TASK) GNUNET_SCHEDULER_cancel (peer->send_task); if ((peer->th != NULL) && (coreAPI != NULL)) GNUNET_CORE_notify_transmit_ready_cancel (peer->th); pos = peer->head; while (pos != NULL) /* Remove any pending messages for this peer */ { increment_stats ("# dht pending messages discarded (due to disconnect/shutdown)"); next = pos->next; GNUNET_free (pos); pos = next; } GNUNET_assert (GNUNET_CONTAINER_multihashmap_contains (all_known_peers, &peer->id.hashPubKey)); GNUNET_assert (GNUNET_YES == GNUNET_CONTAINER_multihashmap_remove (all_known_peers, &peer->id.hashPubKey, peer)); GNUNET_free (peer); } /** * Iterator over hash map entries. * * @param cls closure * @param key current key code * @param value PeerInfo of the peer to move to new lowest bucket * @return GNUNET_YES if we should continue to * iterate, * GNUNET_NO if not. */ static int move_lowest_bucket (void *cls, const GNUNET_HashCode * key, void *value) { struct PeerInfo *peer = value; int new_bucket; GNUNET_assert (lowest_bucket > 0); new_bucket = lowest_bucket - 1; remove_peer (peer, lowest_bucket); GNUNET_CONTAINER_DLL_insert_after (k_buckets[new_bucket].head, k_buckets[new_bucket].tail, k_buckets[new_bucket].tail, peer); k_buckets[new_bucket].peers_size++; return GNUNET_YES; } /** * The current lowest bucket is full, so change the lowest * bucket to the next lower down, and move any appropriate * entries in the current lowest bucket to the new bucket. */ static void enable_next_bucket () { struct GNUNET_CONTAINER_MultiHashMap *to_remove; struct PeerInfo *pos; GNUNET_assert (lowest_bucket > 0); to_remove = GNUNET_CONTAINER_multihashmap_create (bucket_size); pos = k_buckets[lowest_bucket].head; #if PRINT_TABLES fprintf (stderr, "Printing RT before new bucket\n"); print_routing_table (); #endif /* Populate the array of peers which should be in the next lowest bucket */ while (pos != NULL) { if (find_bucket (&pos->id.hashPubKey) < lowest_bucket) GNUNET_CONTAINER_multihashmap_put (to_remove, &pos->id.hashPubKey, pos, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY); pos = pos->next; } /* Remove peers from lowest bucket, insert into next lowest bucket */ GNUNET_CONTAINER_multihashmap_iterate (to_remove, &move_lowest_bucket, NULL); GNUNET_CONTAINER_multihashmap_destroy (to_remove); lowest_bucket = lowest_bucket - 1; #if PRINT_TABLES fprintf (stderr, "Printing RT after new bucket\n"); print_routing_table (); #endif } /** * Find the closest peer in our routing table to the * given hashcode. * * @return The closest peer in our routing table to the * key, or NULL on error. */ static struct PeerInfo * find_closest_peer (const GNUNET_HashCode * hc) { struct PeerInfo *pos; struct PeerInfo *current_closest; unsigned int lowest_distance; unsigned int temp_distance; int bucket; int count; lowest_distance = -1; if (k_buckets[lowest_bucket].peers_size == 0) return NULL; current_closest = NULL; for (bucket = lowest_bucket; bucket < MAX_BUCKETS; bucket++) { pos = k_buckets[bucket].head; count = 0; while ((pos != NULL) && (count < bucket_size)) { temp_distance = distance (&pos->id.hashPubKey, hc); if (temp_distance <= lowest_distance) { lowest_distance = temp_distance; current_closest = pos; } pos = pos->next; count++; } } GNUNET_assert (current_closest != NULL); return current_closest; } /** * Function called to send a request out to another peer. * Called both for locally initiated requests and those * received from other peers. * * @param msg the encapsulated message * @param peer the peer to forward the message to * @param msg_ctx the context of the message (hop count, bloom, etc.) */ static void forward_message (const struct GNUNET_MessageHeader *msg, struct PeerInfo *peer, struct DHT_MessageContext *msg_ctx) { struct GNUNET_DHT_P2PRouteMessage *route_message; struct P2PPendingMessage *pending; size_t msize; size_t psize; char *route_path; increment_stats (STAT_ROUTE_FORWARDS); GNUNET_assert (peer != NULL); if ((msg_ctx->closest != GNUNET_YES) && (peer == find_closest_peer (&msg_ctx->key))) increment_stats (STAT_ROUTE_FORWARDS_CLOSEST); msize = sizeof (struct GNUNET_DHT_P2PRouteMessage) + ntohs (msg->size) + (msg_ctx->path_history_len * sizeof(struct GNUNET_PeerIdentity)); GNUNET_assert (msize <= GNUNET_SERVER_MAX_MESSAGE_SIZE); psize = sizeof (struct P2PPendingMessage) + msize; pending = GNUNET_malloc (psize); pending->msg = (struct GNUNET_MessageHeader *) &pending[1]; pending->importance = msg_ctx->importance; pending->timeout = msg_ctx->timeout; route_message = (struct GNUNET_DHT_P2PRouteMessage *) pending->msg; route_message->header.size = htons (msize); route_message->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_ROUTE); route_message->options = htonl (msg_ctx->msg_options); route_message->hop_count = htonl (msg_ctx->hop_count + 1); route_message->network_size = htonl (msg_ctx->network_size); route_message->desired_replication_level = htonl (msg_ctx->replication); route_message->unique_id = GNUNET_htonll (msg_ctx->unique_id); if (msg_ctx->bloom != NULL) GNUNET_assert (GNUNET_OK == GNUNET_CONTAINER_bloomfilter_get_raw_data (msg_ctx->bloom, route_message-> bloomfilter, DHT_BLOOM_SIZE)); memcpy (&route_message->key, &msg_ctx->key, sizeof (GNUNET_HashCode)); memcpy (&route_message[1], msg, ntohs (msg->size)); if (GNUNET_DHT_RO_RECORD_ROUTE == (msg_ctx->msg_options & GNUNET_DHT_RO_RECORD_ROUTE)) { route_message->outgoing_path_length = htonl(msg_ctx->path_history_len); /* Set pointer to start of enc_msg */ route_path = (char *)&route_message[1]; /* Offset to the end of the enc_msg */ route_path += ntohs (msg->size); /* Copy the route_path after enc_msg */ memcpy (route_path, msg_ctx->path_history, msg_ctx->path_history_len * sizeof(struct GNUNET_PeerIdentity)); } #if DEBUG_DHT > 1 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Adding pending message size %d for peer %s\n", my_short_id, "DHT", msize, GNUNET_i2s (&peer->id)); #endif peer->pending_count++; increment_stats ("# pending messages scheduled"); GNUNET_CONTAINER_DLL_insert_after (peer->head, peer->tail, peer->tail, pending); if (peer->send_task == GNUNET_SCHEDULER_NO_TASK) peer->send_task = GNUNET_SCHEDULER_add_now (&try_core_send, peer); } #if DO_PING /** * Task used to send ping messages to peers so that * they don't get disconnected. * * @param cls the peer to send a ping message to * @param tc context, reason, etc. */ static void periodic_ping_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct PeerInfo *peer = cls; struct GNUNET_MessageHeader ping_message; struct DHT_MessageContext msg_ctx; if ( (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0) return; ping_message.size = htons (sizeof (struct GNUNET_MessageHeader)); ping_message.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_PING); memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext)); #if DEBUG_PING GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "%s:%s Sending periodic ping to %s\n", my_short_id, "DHT", GNUNET_i2s (&peer->id)); #endif forward_message (&ping_message, peer, &msg_ctx); peer->ping_task = GNUNET_SCHEDULER_add_delayed (DHT_DEFAULT_PING_DELAY, &periodic_ping_task, peer); } /** * Schedule PING messages for the top X peers in each * bucket of the routing table (so core won't disconnect them!) */ void schedule_ping_messages () { unsigned int bucket; unsigned int count; struct PeerInfo *pos; for (bucket = lowest_bucket; bucket < MAX_BUCKETS; bucket++) { pos = k_buckets[bucket].head; count = 0; while (pos != NULL) { if ((count < bucket_size) && (pos->ping_task == GNUNET_SCHEDULER_NO_TASK)) GNUNET_SCHEDULER_add_now (&periodic_ping_task, pos); else if ((count >= bucket_size) && (pos->ping_task != GNUNET_SCHEDULER_NO_TASK)) { GNUNET_SCHEDULER_cancel (pos->ping_task); pos->ping_task = GNUNET_SCHEDULER_NO_TASK; } pos = pos->next; count++; } } } #endif /** * Attempt to add a peer to our k-buckets. * * @param peer the peer identity of the peer being added * @param bucket the bucket that we want this peer to go in * @param atsi transport ATS information * * @return NULL if the peer was not added, * pointer to PeerInfo for new peer otherwise */ static struct PeerInfo * try_add_peer (const struct GNUNET_PeerIdentity *peer, unsigned int bucket, const struct GNUNET_TRANSPORT_ATS_Information *atsi) { int peer_bucket; struct PeerInfo *new_peer; if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity))) return NULL; peer_bucket = find_current_bucket (&peer->hashPubKey); GNUNET_assert (peer_bucket >= lowest_bucket); new_peer = add_peer (peer, peer_bucket, atsi); if ((k_buckets[lowest_bucket].peers_size) >= bucket_size) enable_next_bucket (); #if DO_PING schedule_ping_messages (); #endif return new_peer; } /** * Task run to check for messages that need to be sent to a client. * * @param client a ClientList, containing the client and any messages to be sent to it */ static void process_pending_messages (struct ClientList *client) { if (client->pending_head == NULL) return; if (client->transmit_handle != NULL) return; client->transmit_handle = GNUNET_SERVER_notify_transmit_ready (client->client_handle, ntohs (client->pending_head-> msg->size), GNUNET_TIME_UNIT_FOREVER_REL, &send_generic_reply, client); } /** * Callback called as a result of issuing a GNUNET_SERVER_notify_transmit_ready * request. A ClientList is passed as closure, take the head of the list * and copy it into buf, which has the result of sending the message to the * client. * * @param cls closure to this call * @param size maximum number of bytes available to send * @param buf where to copy the actual message to * * @return the number of bytes actually copied, 0 indicates failure */ static size_t send_generic_reply (void *cls, size_t size, void *buf) { struct ClientList *client = cls; char *cbuf = buf; struct PendingMessage *reply; size_t off; size_t msize; client->transmit_handle = NULL; if (buf == NULL) { /* client disconnected */ return 0; } off = 0; while ((NULL != (reply = client->pending_head)) && (size >= off + (msize = ntohs (reply->msg->size)))) { GNUNET_CONTAINER_DLL_remove (client->pending_head, client->pending_tail, reply); memcpy (&cbuf[off], reply->msg, msize); GNUNET_free (reply); off += msize; } process_pending_messages (client); #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Transmitted %u bytes of replies to client\n", (unsigned int) off); #endif return off; } /** * Add a PendingMessage to the clients list of messages to be sent * * @param client the active client to send the message to * @param pending_message the actual message to send */ static void add_pending_message (struct ClientList *client, struct PendingMessage *pending_message) { GNUNET_CONTAINER_DLL_insert_after (client->pending_head, client->pending_tail, client->pending_tail, pending_message); process_pending_messages (client); } /** * Called when a reply needs to be sent to a client, as * a result it found to a GET or FIND PEER request. * * @param client the client to send the reply to * @param message the encapsulated message to send * @param msg_ctx the context of the received message */ static void send_reply_to_client (struct ClientList *client, const struct GNUNET_MessageHeader *message, struct DHT_MessageContext *msg_ctx) { struct GNUNET_DHT_RouteResultMessage *reply; struct PendingMessage *pending_message; uint16_t msize; size_t tsize; char *reply_offset; #if DEBUG_PATH char *path_offset; unsigned int i; #endif #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Sending reply to client.\n", my_short_id, "DHT"); #endif msize = ntohs (message->size); tsize = sizeof (struct GNUNET_DHT_RouteResultMessage) + msize + (msg_ctx->path_history_len * sizeof(struct GNUNET_PeerIdentity)); if (tsize >= GNUNET_SERVER_MAX_MESSAGE_SIZE) { GNUNET_break_op (0); return; } pending_message = GNUNET_malloc (sizeof (struct PendingMessage) + tsize); pending_message->msg = (struct GNUNET_MessageHeader *) &pending_message[1]; reply = (struct GNUNET_DHT_RouteResultMessage *) &pending_message[1]; reply->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_LOCAL_ROUTE_RESULT); reply->header.size = htons (tsize); reply->outgoing_path_length = htonl(msg_ctx->path_history_len); reply->unique_id = GNUNET_htonll (msg_ctx->unique_id); memcpy (&reply->key, &msg_ctx->key, sizeof (GNUNET_HashCode)); reply_offset = (char *)&reply[1]; memcpy (&reply[1], message, msize); if (msg_ctx->path_history_len > 0) { reply_offset += msize; memcpy(reply_offset, msg_ctx->path_history, msg_ctx->path_history_len * sizeof(struct GNUNET_PeerIdentity)); } #if DEBUG_PATH GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Returning message with outgoing path length %d\n", msg_ctx->path_history_len); for (i = 0; i < msg_ctx->path_history_len; i++) { path_offset = &msg_ctx->path_history[i * sizeof(struct GNUNET_PeerIdentity)]; GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Found peer %d:%s\n", i, GNUNET_i2s((struct GNUNET_PeerIdentity *)path_offset)); } #endif add_pending_message (client, pending_message); } /** * Consider whether or not we would like to have this peer added to * our routing table. Check whether bucket for this peer is full, * if so return negative; if not return positive. Since peers are * only added on CORE level connect, this doesn't actually add the * peer to the routing table. * * @param peer the peer we are considering adding * * @return GNUNET_YES if we want this peer, GNUNET_NO if not (bucket * already full) */ static int consider_peer (struct GNUNET_PeerIdentity *peer) { int bucket; if ((GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains (all_known_peers, &peer->hashPubKey)) || (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))) return GNUNET_NO; /* We already know this peer (are connected even!) */ bucket = find_current_bucket (&peer->hashPubKey); if ((k_buckets[bucket].peers_size < bucket_size) || ((bucket == lowest_bucket) && (lowest_bucket > 0))) return GNUNET_YES; return GNUNET_NO; } /** * Task used to remove forwarding entries, either * after timeout, when full, or on shutdown. * * @param cls the entry to remove * @param tc context, reason, etc. */ static void remove_forward_entry (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct DHTRouteSource *source_info = cls; struct DHTQueryRecord *record; source_info = GNUNET_CONTAINER_heap_remove_node (source_info->hnode); record = source_info->record; GNUNET_CONTAINER_DLL_remove (record->head, record->tail, source_info); if (record->head == NULL) /* No more entries in DLL */ { GNUNET_assert (GNUNET_YES == GNUNET_CONTAINER_multihashmap_remove (forward_list.hashmap, &record->key, record)); GNUNET_free (record); } if (source_info->find_peers_responded != NULL) GNUNET_CONTAINER_bloomfilter_free (source_info->find_peers_responded); GNUNET_free (source_info); } /** * Main function that handles whether or not to route a result * message to other peers, or to send to our local client. * * @param msg the result message to be routed * @param msg_ctx context of the message we are routing * * @return the number of peers the message was routed to, * GNUNET_SYSERR on failure */ static int route_result_message (struct GNUNET_MessageHeader *msg, struct DHT_MessageContext *msg_ctx) { struct GNUNET_PeerIdentity new_peer; struct DHTQueryRecord *record; struct DHTRouteSource *pos; struct PeerInfo *peer_info; const struct GNUNET_MessageHeader *hello_msg; #if DEBUG_DHT > 1 unsigned int i; #endif increment_stats (STAT_RESULTS); /** * If a find peer result message is received and contains a valid * HELLO for another peer, offer it to the transport service. */ if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DHT_FIND_PEER_RESULT) { if (ntohs (msg->size) <= sizeof (struct GNUNET_MessageHeader)) GNUNET_break_op (0); hello_msg = &msg[1]; if ((ntohs (hello_msg->type) != GNUNET_MESSAGE_TYPE_HELLO) || (GNUNET_SYSERR == GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) hello_msg, &new_peer))) { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "%s:%s Received non-HELLO message type in find peer result message!\n", my_short_id, "DHT"); GNUNET_break_op (0); return GNUNET_NO; } else /* We have a valid hello, and peer id stored in new_peer */ { find_peer_context.count++; increment_stats (STAT_FIND_PEER_REPLY); if (GNUNET_YES == consider_peer (&new_peer)) { increment_stats (STAT_HELLOS_PROVIDED); GNUNET_TRANSPORT_offer_hello (transport_handle, hello_msg, NULL, NULL); GNUNET_CORE_peer_request_connect (coreAPI, GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5), &new_peer, NULL, NULL); } } } if (malicious_dropper == GNUNET_YES) record = NULL; else record = GNUNET_CONTAINER_multihashmap_get (forward_list.hashmap, &msg_ctx->key); if (record == NULL) /* No record of this message! */ { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Have no record of response key %s uid %llu\n", my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key), msg_ctx->unique_id); #endif #if DEBUG_DHT_ROUTING if ((debug_routes_extended) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_RESULT, msg_ctx->hop_count, GNUNET_SYSERR, &my_identity, &msg_ctx->key, msg_ctx->peer, NULL); } #endif if (msg_ctx->bloom != NULL) { GNUNET_CONTAINER_bloomfilter_free (msg_ctx->bloom); msg_ctx->bloom = NULL; } return 0; } pos = record->head; while (pos != NULL) { #if STRICT_FORWARDING if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DHT_FIND_PEER_RESULT) /* If we have already forwarded this peer id, don't do it again! */ { if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (pos->find_peers_responded, &new_peer.hashPubKey)) { increment_stats ("# find peer responses NOT forwarded (bloom match)"); pos = pos->next; continue; } else GNUNET_CONTAINER_bloomfilter_add (pos->find_peers_responded, &new_peer.hashPubKey); } #endif if (0 == memcmp (&pos->source, &my_identity, sizeof (struct GNUNET_PeerIdentity))) /* Local client (or DHT) initiated request! */ { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Sending response key %s uid %llu to client\n", my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key), msg_ctx->unique_id); #endif #if DEBUG_DHT_ROUTING if ((debug_routes_extended) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_RESULT, msg_ctx->hop_count, GNUNET_YES, &my_identity, &msg_ctx->key, msg_ctx->peer, NULL); } #endif increment_stats (STAT_RESULTS_TO_CLIENT); if (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DHT_GET_RESULT) increment_stats (STAT_GET_REPLY); #if DEBUG_DHT > 1 for (i = 0; i < msg_ctx->path_history_len; i++) { char *path_offset; path_offset = &msg_ctx->path_history[i * sizeof(struct GNUNET_PeerIdentity)]; GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "(before client) Key %s Found peer %d:%s\n", GNUNET_h2s(&msg_ctx->key), i, GNUNET_i2s((struct GNUNET_PeerIdentity *)path_offset)); } #endif send_reply_to_client (pos->client, msg, msg_ctx); } else /* Send to peer */ { peer_info = find_peer_by_id (&pos->source); if (peer_info == NULL) /* Didn't find the peer in our routing table, perhaps peer disconnected! */ { pos = pos->next; continue; } if (msg_ctx->bloom == NULL) msg_ctx->bloom = GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K); GNUNET_CONTAINER_bloomfilter_add (msg_ctx->bloom, &my_identity.hashPubKey); if ((GNUNET_NO == GNUNET_CONTAINER_bloomfilter_test (msg_ctx->bloom, &peer_info->id.hashPubKey))) { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Forwarding response key %s uid %llu to peer %s\n", my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key), msg_ctx->unique_id, GNUNET_i2s (&peer_info->id)); #endif #if DEBUG_DHT_ROUTING if ((debug_routes_extended) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_RESULT, msg_ctx->hop_count, GNUNET_NO, &my_identity, &msg_ctx->key, msg_ctx->peer, &pos->source); } #endif forward_result_message (msg, peer_info, msg_ctx); /* Try removing forward entries after sending once, only allows ONE response per request */ if (pos->delete_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (pos->delete_task); pos->delete_task = GNUNET_SCHEDULER_add_now (&remove_forward_entry, pos); } } else { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': NOT Forwarding response (bloom match) key %s uid %llu to peer %s\n", my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key), msg_ctx->unique_id, GNUNET_i2s (&peer_info->id)); #endif } } pos = pos->next; } if (msg_ctx->bloom != NULL) { GNUNET_CONTAINER_bloomfilter_free (msg_ctx->bloom); msg_ctx->bloom = NULL; } return 0; } /** * Iterator for local get request results, * * @param cls closure for iterator, a DatacacheGetContext * @param exp when does this value expire? * @param key the key this data is stored under * @param size the size of the data identified by key * @param data the actual data * @param type the type of the data * * @return GNUNET_OK to continue iteration, anything else * to stop iteration. */ static int datacache_get_iterator (void *cls, struct GNUNET_TIME_Absolute exp, const GNUNET_HashCode * key, size_t size, const char *data, enum GNUNET_BLOCK_Type type) { struct DHT_MessageContext *msg_ctx = cls; struct DHT_MessageContext *new_msg_ctx; struct GNUNET_DHT_GetResultMessage *get_result; enum GNUNET_BLOCK_EvaluationResult eval; const struct DHTPutEntry *put_entry; int get_size; char *path_offset; #if DEBUG_PATH unsigned int i; #endif #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Received `%s' response from datacache\n", my_short_id, "DHT", "GET"); #endif put_entry = (const struct DHTPutEntry *)data; if (size != sizeof(struct DHTPutEntry) + put_entry->data_size + (put_entry->path_length * sizeof(struct GNUNET_PeerIdentity))) { GNUNET_log( GNUNET_ERROR_TYPE_WARNING, "Path + data size doesn't add up for data inserted into datacache!\nData size %d, path length %d, expected %d, got %d\n", put_entry->data_size, put_entry->path_length, sizeof(struct DHTPutEntry) + put_entry->data_size + (put_entry->path_length * sizeof(struct GNUNET_PeerIdentity)), size); msg_ctx->do_forward = GNUNET_NO; return GNUNET_OK; } eval = GNUNET_BLOCK_evaluate (block_context, type, key, &msg_ctx->reply_bf, msg_ctx->reply_bf_mutator, msg_ctx->xquery, msg_ctx->xquery_size, &put_entry[1], put_entry->data_size); switch (eval) { case GNUNET_BLOCK_EVALUATION_OK_LAST: msg_ctx->do_forward = GNUNET_NO; case GNUNET_BLOCK_EVALUATION_OK_MORE: new_msg_ctx = GNUNET_malloc (sizeof (struct DHT_MessageContext)); memcpy (new_msg_ctx, msg_ctx, sizeof (struct DHT_MessageContext)); if (GNUNET_DHT_RO_RECORD_ROUTE == (msg_ctx->msg_options & GNUNET_DHT_RO_RECORD_ROUTE)) { new_msg_ctx->msg_options = GNUNET_DHT_RO_RECORD_ROUTE; new_msg_ctx->path_history_len = msg_ctx->path_history_len; /* Assign to previous msg_ctx path history, caller should free after our return */ new_msg_ctx->path_history = msg_ctx->path_history; #if DEBUG_PATH for (i = 0; i < new_msg_ctx->path_history_len; i++) { path_offset = &new_msg_ctx->path_history[i * sizeof(struct GNUNET_PeerIdentity)]; GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "(get_iterator) Key %s Found peer %d:%s\n", GNUNET_h2s(&msg_ctx->key), i, GNUNET_i2s((struct GNUNET_PeerIdentity *)path_offset)); } #endif } get_size = sizeof (struct GNUNET_DHT_GetResultMessage) + put_entry->data_size + (put_entry->path_length * sizeof(struct GNUNET_PeerIdentity)); get_result = GNUNET_malloc (get_size); get_result->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_GET_RESULT); get_result->header.size = htons (get_size); get_result->expiration = GNUNET_TIME_absolute_hton (exp); get_result->type = htons (type); get_result->put_path_length = htons(put_entry->path_length); path_offset = (char *)&put_entry[1]; path_offset += put_entry->data_size; #if DEBUG_PATH for (i = 0; i < put_entry->path_length; i++) { GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "(get_iterator PUT path) Key %s Found peer %d:%s\n", GNUNET_h2s(&msg_ctx->key), i, GNUNET_i2s((struct GNUNET_PeerIdentity *)&path_offset[i * sizeof(struct GNUNET_PeerIdentity)])); } #endif /* Copy the actual data and the path_history to the end of the get result */ memcpy (&get_result[1], &put_entry[1], put_entry->data_size + (put_entry->path_length * sizeof(struct GNUNET_PeerIdentity))); new_msg_ctx->peer = &my_identity; new_msg_ctx->bloom = GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K); new_msg_ctx->hop_count = 0; new_msg_ctx->importance = DHT_DEFAULT_P2P_IMPORTANCE + 2; /* Make result routing a higher priority */ new_msg_ctx->timeout = DHT_DEFAULT_P2P_TIMEOUT; increment_stats (STAT_GET_RESPONSE_START); route_result_message (&get_result->header, new_msg_ctx); GNUNET_free (new_msg_ctx); GNUNET_free (get_result); break; case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE: #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Duplicate block error\n", my_short_id, "DHT"); #endif break; case GNUNET_BLOCK_EVALUATION_RESULT_INVALID: #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "`%s:%s': Invalid request error\n", my_short_id, "DHT"); #endif break; case GNUNET_BLOCK_EVALUATION_REQUEST_VALID: #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Valid request, no results.\n", my_short_id, "DHT"); #endif GNUNET_break (0); break; case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID: GNUNET_break_op (0); msg_ctx->do_forward = GNUNET_NO; break; case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED: #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "`%s:%s': Unsupported block type (%u) in response!\n", my_short_id, "DHT", type); #endif /* msg_ctx->do_forward = GNUNET_NO; // not sure... */ break; } return GNUNET_OK; } /** * Main function that handles whether or not to route a message to other * peers. * * @param msg the message to be routed * @param msg_ctx the context containing all pertinent information about the message */ static void route_message (const struct GNUNET_MessageHeader *msg, struct DHT_MessageContext *msg_ctx); /** * Server handler for all dht get requests, look for data, * if found, send response either to clients or other peers. * * @param msg the actual get message * @param msg_ctx struct containing pertinent information about the get request * * @return number of items found for GET request */ static unsigned int handle_dht_get (const struct GNUNET_MessageHeader *msg, struct DHT_MessageContext *msg_ctx) { const struct GNUNET_DHT_GetMessage *get_msg; uint16_t msize; uint16_t bf_size; unsigned int results; const char *end; enum GNUNET_BLOCK_Type type; msize = ntohs (msg->size); if (msize < sizeof (struct GNUNET_DHT_GetMessage)) { GNUNET_break (0); return 0; } get_msg = (const struct GNUNET_DHT_GetMessage *) msg; bf_size = ntohs (get_msg->bf_size); msg_ctx->xquery_size = ntohs (get_msg->xquery_size); msg_ctx->reply_bf_mutator = get_msg->bf_mutator; /* FIXME: ntohl? */ if (msize != sizeof (struct GNUNET_DHT_GetMessage) + bf_size + msg_ctx->xquery_size) { GNUNET_break (0); return 0; } end = (const char *) &get_msg[1]; if (msg_ctx->xquery_size == 0) { msg_ctx->xquery = NULL; } else { msg_ctx->xquery = (const void *) end; end += msg_ctx->xquery_size; } if (bf_size == 0) { msg_ctx->reply_bf = NULL; } else { msg_ctx->reply_bf = GNUNET_CONTAINER_bloomfilter_init (end, bf_size, GNUNET_DHT_GET_BLOOMFILTER_K); } type = (enum GNUNET_BLOCK_Type) ntohl (get_msg->type); #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Received `%s' request, message type %u, key %s, uid %llu\n", my_short_id, "DHT", "GET", type, GNUNET_h2s (&msg_ctx->key), msg_ctx->unique_id); #endif increment_stats (STAT_GETS); results = 0; #if HAVE_MALICIOUS if (type == GNUNET_BLOCK_DHT_MALICIOUS_MESSAGE_TYPE) { GNUNET_CONTAINER_bloomfilter_free (msg_ctx->reply_bf); return results; } #endif msg_ctx->do_forward = GNUNET_YES; if (datacache != NULL) results = GNUNET_DATACACHE_get (datacache, &msg_ctx->key, type, &datacache_get_iterator, msg_ctx); #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Found %d results for `%s' request uid %llu\n", my_short_id, "DHT", results, "GET", msg_ctx->unique_id); #endif if (results >= 1) { #if DEBUG_DHT_ROUTING if ((debug_routes) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_GET, msg_ctx->hop_count, GNUNET_YES, &my_identity, &msg_ctx->key); } if ((debug_routes_extended) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE, msg_ctx->hop_count, GNUNET_YES, &my_identity, &msg_ctx->key, msg_ctx->peer, NULL); } #endif } else { /* check query valid */ if (GNUNET_BLOCK_EVALUATION_REQUEST_INVALID == GNUNET_BLOCK_evaluate (block_context, type, &msg_ctx->key, &msg_ctx->reply_bf, msg_ctx->reply_bf_mutator, msg_ctx->xquery, msg_ctx->xquery_size, NULL, 0)) { GNUNET_break_op (0); msg_ctx->do_forward = GNUNET_NO; } } if (msg_ctx->hop_count == 0) /* Locally initiated request */ { #if DEBUG_DHT_ROUTING if ((debug_routes) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_GET, msg_ctx->hop_count, GNUNET_NO, &my_identity, &msg_ctx->key); } #endif } if (msg_ctx->do_forward == GNUNET_YES) route_message (msg, msg_ctx); GNUNET_CONTAINER_bloomfilter_free (msg_ctx->reply_bf); return results; } static void remove_recent_find_peer (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { GNUNET_HashCode *key = cls; GNUNET_assert (GNUNET_YES == GNUNET_CONTAINER_multihashmap_remove (recent_find_peer_requests, key, NULL)); GNUNET_free (key); } /** * Server handler for initiating local dht find peer requests * * @param find_msg the actual find peer message * @param msg_ctx struct containing pertinent information about the request * */ static void handle_dht_find_peer (const struct GNUNET_MessageHeader *find_msg, struct DHT_MessageContext *msg_ctx) { struct GNUNET_MessageHeader *find_peer_result; struct GNUNET_DHT_FindPeerMessage *find_peer_message; struct DHT_MessageContext *new_msg_ctx; struct GNUNET_CONTAINER_BloomFilter *incoming_bloom; size_t hello_size; size_t tsize; GNUNET_HashCode *recent_hash; struct GNUNET_MessageHeader *other_hello; size_t other_hello_size; struct GNUNET_PeerIdentity peer_id; find_peer_message = (struct GNUNET_DHT_FindPeerMessage *) find_msg; GNUNET_break_op (ntohs (find_msg->size) >= (sizeof (struct GNUNET_DHT_FindPeerMessage))); if (ntohs (find_msg->size) < sizeof (struct GNUNET_DHT_FindPeerMessage)) return; other_hello = NULL; other_hello_size = 0; if (ntohs (find_msg->size) > sizeof (struct GNUNET_DHT_FindPeerMessage)) { other_hello_size = ntohs (find_msg->size) - sizeof (struct GNUNET_DHT_FindPeerMessage); other_hello = GNUNET_malloc (other_hello_size); memcpy (other_hello, &find_peer_message[1], other_hello_size); if ((GNUNET_HELLO_size ((struct GNUNET_HELLO_Message *) other_hello) == 0) || (GNUNET_OK != GNUNET_HELLO_get_id ((struct GNUNET_HELLO_Message *) other_hello, &peer_id))) { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Received invalid HELLO message in find peer request!\n"); GNUNET_free (other_hello); return; } #if FIND_PEER_WITH_HELLO if (GNUNET_YES == consider_peer (&peer_id)) { increment_stats (STAT_HELLOS_PROVIDED); GNUNET_TRANSPORT_offer_hello (transport_handle, other_hello, NULL, NULL); GNUNET_CORE_peer_request_connect (coreAPI, GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5), &peer_id, NULL, NULL); route_message (find_msg, msg_ctx); GNUNET_free (other_hello); return; } else /* We don't want this peer! */ { route_message (find_msg, msg_ctx); GNUNET_free (other_hello); return; } #endif } #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Received `%s' request from client, key %s (msg size %d, we expected %d)\n", my_short_id, "DHT", "FIND PEER", GNUNET_h2s (&msg_ctx->key), ntohs (find_msg->size), sizeof (struct GNUNET_MessageHeader)); #endif if (my_hello == NULL) { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s': Our HELLO is null, can't return.\n", "DHT"); #endif GNUNET_free_non_null (other_hello); route_message (find_msg, msg_ctx); return; } incoming_bloom = GNUNET_CONTAINER_bloomfilter_init (find_peer_message->bloomfilter, DHT_BLOOM_SIZE, DHT_BLOOM_K); if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (incoming_bloom, &my_identity.hashPubKey)) { increment_stats (STAT_BLOOM_FIND_PEER); GNUNET_CONTAINER_bloomfilter_free (incoming_bloom); GNUNET_free_non_null (other_hello); route_message (find_msg, msg_ctx); return; /* We match the bloomfilter, do not send a response to this peer (they likely already know us!) */ } GNUNET_CONTAINER_bloomfilter_free (incoming_bloom); #if RESTRICT_FIND_PEER /** * Ignore any find peer requests from a peer we have seen very recently. */ 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! */ { increment_stats ("# dht find peer requests ignored (recently seen!)"); GNUNET_free_non_null (other_hello); return; } /** * Use this check to only allow the peer to respond to find peer requests if * it would be beneficial to have the requesting peer in this peers routing * table. Can be used to thwart peers flooding the network with find peer * requests that we don't care about. However, if a new peer is joining * the network and has no other peers this is a problem (assume all buckets * full, no one will respond!). */ memcpy (&peer_id.hashPubKey, &msg_ctx->key, sizeof (GNUNET_HashCode)); if (GNUNET_NO == consider_peer (&peer_id)) { increment_stats ("# dht find peer requests ignored (do not need!)"); GNUNET_free_non_null (other_hello); route_message (find_msg, msg_ctx); return; } #endif recent_hash = GNUNET_malloc (sizeof (GNUNET_HashCode)); memcpy (recent_hash, &msg_ctx->key, sizeof (GNUNET_HashCode)); if (GNUNET_SYSERR != GNUNET_CONTAINER_multihashmap_put (recent_find_peer_requests, &msg_ctx->key, NULL, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)) { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Adding recent remove task for key `%s`!\n", GNUNET_h2s (&msg_ctx->key)); #endif /* Only add a task if there wasn't one for this key already! */ GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30), &remove_recent_find_peer, recent_hash); } else { GNUNET_free (recent_hash); #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received duplicate find peer request too soon!\n"); #endif } /* Simplistic find_peer functionality, always return our hello */ hello_size = ntohs (my_hello->size); tsize = hello_size + sizeof (struct GNUNET_MessageHeader); if (tsize >= GNUNET_SERVER_MAX_MESSAGE_SIZE) { GNUNET_break_op (0); GNUNET_free_non_null (other_hello); return; } find_peer_result = GNUNET_malloc (tsize); find_peer_result->type = htons (GNUNET_MESSAGE_TYPE_DHT_FIND_PEER_RESULT); find_peer_result->size = htons (tsize); memcpy (&find_peer_result[1], my_hello, hello_size); #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s': Sending hello size %d to requesting peer.\n", "DHT", hello_size); #endif new_msg_ctx = GNUNET_malloc (sizeof (struct DHT_MessageContext)); memcpy (new_msg_ctx, msg_ctx, sizeof (struct DHT_MessageContext)); new_msg_ctx->peer = &my_identity; new_msg_ctx->bloom = GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K); new_msg_ctx->hop_count = 0; new_msg_ctx->importance = DHT_DEFAULT_P2P_IMPORTANCE + 2; /* Make find peer requests a higher priority */ new_msg_ctx->timeout = DHT_DEFAULT_P2P_TIMEOUT; increment_stats (STAT_FIND_PEER_ANSWER); if (GNUNET_DHT_RO_RECORD_ROUTE == (msg_ctx->msg_options & GNUNET_DHT_RO_RECORD_ROUTE)) { new_msg_ctx->msg_options = GNUNET_DHT_RO_RECORD_ROUTE; new_msg_ctx->path_history_len = msg_ctx->path_history_len; /* Assign to previous msg_ctx path history, caller should free after our return */ new_msg_ctx->path_history = msg_ctx->path_history; } route_result_message (find_peer_result, new_msg_ctx); GNUNET_free (new_msg_ctx); #if DEBUG_DHT_ROUTING if ((debug_routes) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_FIND_PEER, msg_ctx->hop_count, GNUNET_YES, &my_identity, &msg_ctx->key); } #endif GNUNET_free_non_null (other_hello); GNUNET_free (find_peer_result); route_message (find_msg, msg_ctx); } /** * Task used to republish data. * Forward declaration; function call loop. * * @param cls closure (a struct RepublishContext) * @param tc runtime context for this task */ static void republish_content (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc); /** * Server handler for initiating local dht put requests * * @param msg the actual put message * @param msg_ctx struct containing pertinent information about the request */ static void handle_dht_put (const struct GNUNET_MessageHeader *msg, struct DHT_MessageContext *msg_ctx) { const struct GNUNET_DHT_PutMessage *put_msg; struct DHTPutEntry *put_entry; unsigned int put_size; char *path_offset; enum GNUNET_BLOCK_Type put_type; size_t data_size; int ret; struct RepublishContext *put_context; GNUNET_HashCode key; GNUNET_assert (ntohs (msg->size) >= sizeof (struct GNUNET_DHT_PutMessage)); put_msg = (const struct GNUNET_DHT_PutMessage *) msg; put_type = (enum GNUNET_BLOCK_Type) ntohl (put_msg->type); #if HAVE_MALICIOUS if (put_type == GNUNET_BLOCK_DHT_MALICIOUS_MESSAGE_TYPE) { #if DEBUG_DHT_ROUTING if ((debug_routes_extended) && (dhtlog_handle != NULL)) { /** Log routes that die due to high load! */ dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE, msg_ctx->hop_count, GNUNET_SYSERR, &my_identity, &msg_ctx->key, msg_ctx->peer, NULL); } #endif return; } #endif data_size = ntohs (put_msg->header.size) - sizeof (struct GNUNET_DHT_PutMessage); ret = GNUNET_BLOCK_get_key (block_context, put_type, &put_msg[1], data_size, &key); if (GNUNET_NO == ret) { #if DEBUG_DHT_ROUTING if ((debug_routes_extended) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE, msg_ctx->hop_count, GNUNET_SYSERR, &my_identity, &msg_ctx->key, msg_ctx->peer, NULL); } #endif /* invalid reply */ GNUNET_break_op (0); return; } if ((GNUNET_YES == ret) && (0 != memcmp (&key, &msg_ctx->key, sizeof (GNUNET_HashCode)))) { #if DEBUG_DHT_ROUTING if ((debug_routes_extended) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE, msg_ctx->hop_count, GNUNET_SYSERR, &my_identity, &msg_ctx->key, msg_ctx->peer, NULL); } #endif /* invalid wrapper: key mismatch! */ GNUNET_break_op (0); return; } /* ret == GNUNET_SYSERR means that there is no known relationship between data and the key, so we cannot check it */ #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Received `%s' request (inserting data!), message type %d, key %s, uid %llu\n", my_short_id, "DHT", "PUT", put_type, GNUNET_h2s (&msg_ctx->key), msg_ctx->unique_id); #endif #if DEBUG_DHT_ROUTING if (msg_ctx->hop_count == 0) /* Locally initiated request */ { if ((debug_routes) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_PUT, msg_ctx->hop_count, GNUNET_NO, &my_identity, &msg_ctx->key); } } #endif if (msg_ctx->closest != GNUNET_YES) { route_message (msg, msg_ctx); return; } #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Received `%s' request (inserting data!), message type %d, key %s, uid %llu\n", my_short_id, "DHT", "PUT", put_type, GNUNET_h2s (&msg_ctx->key), msg_ctx->unique_id); #endif #if DEBUG_DHT_ROUTING if ((debug_routes_extended) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE, msg_ctx->hop_count, GNUNET_YES, &my_identity, &msg_ctx->key, msg_ctx->peer, NULL); } if ((debug_routes) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_PUT, msg_ctx->hop_count, GNUNET_YES, &my_identity, &msg_ctx->key); } #endif increment_stats (STAT_PUTS_INSERTED); if (datacache != NULL) { /* Put size is actual data size plus struct overhead plus path length (if any) */ put_size = data_size + sizeof(struct DHTPutEntry) + (msg_ctx->path_history_len * sizeof(struct GNUNET_PeerIdentity)); put_entry = GNUNET_malloc(put_size); put_entry->data_size = data_size; put_entry->path_length = msg_ctx->path_history_len; /* Copy data to end of put entry */ memcpy(&put_entry[1], &put_msg[1], data_size); if (msg_ctx->path_history_len > 0) { /* Copy path after data */ path_offset = (char *)&put_entry[1]; path_offset += data_size; memcpy(path_offset, msg_ctx->path_history, msg_ctx->path_history_len * sizeof(struct GNUNET_PeerIdentity)); } ret = GNUNET_DATACACHE_put (datacache, &msg_ctx->key, put_size, (char *) put_entry, put_type, GNUNET_TIME_absolute_ntoh (put_msg->expiration)); GNUNET_free (put_entry); if ((ret == GNUNET_YES) && (do_republish == GNUNET_YES)) { put_context = GNUNET_malloc (sizeof (struct RepublishContext)); memcpy (&put_context->key, &msg_ctx->key, sizeof (GNUNET_HashCode)); put_context->type = put_type; GNUNET_SCHEDULER_add_delayed (dht_republish_frequency, &republish_content, put_context); } } else GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': %s request received, but have no datacache!\n", my_short_id, "DHT", "PUT"); if (stop_on_closest == GNUNET_NO) route_message (msg, msg_ctx); } /** * Estimate the diameter of the network based * on how many buckets are currently in use. * Concept here is that the diameter of the network * is roughly the distance a message must travel in * order to reach its intended destination. Since * at each hop we expect to get one bit closer, and * we have one bit per bucket, the number of buckets * in use should be the largest number of hops for * a successful message. (of course, this assumes we * know all peers in the network!) * * @return ballpark diameter figure */ static unsigned int estimate_diameter () { return MAX_BUCKETS - lowest_bucket; } /** * To how many peers should we (on average) * forward the request to obtain the desired * target_replication count (on average). * * returns: target_replication / (est. hops) + (target_replication * hop_count) * where est. hops is typically 2 * the routing table depth * * @param hop_count number of hops the message has traversed * @param target_replication the number of total paths desired * * @return Some number of peers to forward the message to */ static unsigned int get_forward_count (unsigned int hop_count, size_t target_replication) { uint32_t random_value; unsigned int forward_count; float target_value; unsigned int diameter; diameter = estimate_diameter (); if (GNUNET_NO == use_max_hops) max_hops = (diameter + 1) * 2; /** * If we are behaving in strict kademlia mode, send multiple initial requests, * but then only send to 1 or 0 peers based strictly on the number of hops. */ if (strict_kademlia == GNUNET_YES) { if (hop_count == 0) return kademlia_replication; else if (hop_count < max_hops) return 1; else return 0; } /* FIXME: the smaller we think the network is the more lenient we should be for * routing right? The estimation below only works if we think we have reasonably * full routing tables, which for our RR topologies may not be the case! */ if (hop_count > max_hops) { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Hop count too high (est %d, lowest %d), NOT Forwarding request\n", my_short_id, "DHT", estimate_diameter (), lowest_bucket); #endif /* FIXME: does this work as intended, isn't the decision to forward or not made based on closeness as well? */ if (GNUNET_YES == paper_forwarding) /* Once we have reached our ideal number of hops, don't stop forwarding! */ { return 1; } return 0; } if (GNUNET_YES == paper_forwarding) { /* FIXME: re-run replication trials with this formula */ target_value = 1 + (target_replication - 1.0) / (diameter + ((float) (target_replication - 1.0) * hop_count)); /* Set forward count to floor of target_value */ forward_count = (unsigned int) target_value; /* Subtract forward_count (floor) from target_value (yields value between 0 and 1) */ target_value = target_value - forward_count; random_value = GNUNET_CRYPTO_random_u32(GNUNET_CRYPTO_QUALITY_STRONG, UINT32_MAX); if (random_value < (target_value * UINT32_MAX)) forward_count += 1; } else { random_value = 0; forward_count = 1; target_value = target_replication / (diameter + ((float) target_replication * hop_count)); if (target_value > 1) { /* Set forward count to floor of target_value */ forward_count = (unsigned int) target_value; /* Subtract forward_count (floor) from target_value (yields value between 0 and 1) */ target_value = target_value - forward_count; } else random_value = GNUNET_CRYPTO_random_u32(GNUNET_CRYPTO_QUALITY_STRONG, UINT32_MAX); if (random_value < (target_value * UINT32_MAX)) forward_count += 1; } return forward_count; } /* * Check whether my identity is closer than any known peers. * If a non-null bloomfilter is given, check if this is the closest * peer that hasn't already been routed to. * * @param target hash code to check closeness to * @param bloom bloomfilter, exclude these entries from the decision * * Return GNUNET_YES if node location is closest, GNUNET_NO * otherwise. */ int am_closest_peer (const GNUNET_HashCode * target, struct GNUNET_CONTAINER_BloomFilter *bloom) { int bits; int other_bits; int bucket_num; int count; struct PeerInfo *pos; unsigned int my_distance; if (0 == memcmp (&my_identity.hashPubKey, target, sizeof (GNUNET_HashCode))) return GNUNET_YES; bucket_num = find_current_bucket (target); bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, target); my_distance = distance (&my_identity.hashPubKey, target); pos = k_buckets[bucket_num].head; count = 0; while ((pos != NULL) && (count < bucket_size)) { if ((bloom != NULL) && (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey))) { pos = pos->next; continue; /* Skip already checked entries */ } other_bits = GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey, target); if (other_bits > bits) return GNUNET_NO; else if (other_bits == bits) /* We match the same number of bits */ { if (strict_kademlia != GNUNET_YES) /* Return that we at as close as any other peer */ return GNUNET_YES; else if (distance (&pos->id.hashPubKey, target) < my_distance) /* Check all known peers, only return if we are the true closest */ return GNUNET_NO; } pos = pos->next; } /* No peers closer, we are the closest! */ return GNUNET_YES; } /** * Return this peers adjusted value based on the convergence * function chosen. This is the key function for randomized * routing decisions. * * @param target the key of the request * @param peer the peer we would like the value of * @param hops number of hops this message has already traveled * * @return bit distance from target to peer raised to an exponent * adjusted based on the current routing convergence algorithm * */ static unsigned long long converge_distance (const GNUNET_HashCode * target, struct PeerInfo *peer, unsigned int hops) { unsigned long long ret; unsigned int other_matching_bits; double base_converge_modifier = .1; /* Value that "looks" good (when plotted), have to start somewhere */ double temp_modifier; double calc_value; double exponent; int curr_max_hops; if (use_max_hops) curr_max_hops = max_hops; else curr_max_hops = (estimate_diameter () + 1) * 2; if (converge_modifier > 0) temp_modifier = converge_modifier * base_converge_modifier; else { temp_modifier = base_converge_modifier; base_converge_modifier = 0.0; } GNUNET_assert (temp_modifier > 0); other_matching_bits = GNUNET_CRYPTO_hash_matching_bits (target, &peer->id.hashPubKey); switch (converge_option) { case DHT_CONVERGE_RANDOM: return 1; /* Always return 1, choose equally among all peers */ case DHT_CONVERGE_LINEAR: calc_value = hops * curr_max_hops * temp_modifier; break; case DHT_CONVERGE_SQUARE: /** * Simple square based curve. */ calc_value = (sqrt (hops) / sqrt (curr_max_hops)) * (curr_max_hops / (curr_max_hops * temp_modifier)); break; case DHT_CONVERGE_EXPONENTIAL: /** * Simple exponential curve. */ if (base_converge_modifier > 0) calc_value = (temp_modifier * hops * hops) / curr_max_hops; else calc_value = (hops * hops) / curr_max_hops; break; case DHT_CONVERGE_BINARY: /** * If below the cutoff, route randomly (return 1), * If above the cutoff, return the maximum possible * value first (always route to closest, because * they are sorted.) */ if (hops >= converge_modifier) /* Past cutoff */ { return ULLONG_MAX; } /* Fall through */ default: return 1; } /* Take the log (base e) of the number of bits matching the other peer */ exponent = log (other_matching_bits); /* Check if we would overflow; our largest possible value is 2^64 approx. e^44.361419555836498 */ if (exponent * calc_value >= 44.361419555836498) return ULLONG_MAX; /* Clear errno and all math exceptions */ errno = 0; feclearexcept (FE_ALL_EXCEPT); ret = (unsigned long long) pow (other_matching_bits, calc_value); if ((errno != 0) || fetestexcept (FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW)) { if (0 != fetestexcept (FE_OVERFLOW)) GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "FE_OVERFLOW\n"); if (0 != fetestexcept (FE_INVALID)) GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "FE_INVALID\n"); if (0 != fetestexcept (FE_UNDERFLOW)) GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "FE_UNDERFLOW\n"); return 0; } else return ret; } /** * Comparison function for two struct PeerInfo's * which have already had their matching bits to * some target calculated. * * @param p1 a pointer pointer to a struct PeerInfo * @param p2 a pointer pointer to a struct PeerInfo * * @return 0 if equidistant to target, * -1 if p1 is closer, * 1 if p2 is closer */ static int compare_peers (const void *p1, const void *p2) { struct PeerInfo **first = (struct PeerInfo **) p1; struct PeerInfo **second = (struct PeerInfo **) p2; if ((*first)->matching_bits > (*second)->matching_bits) return -1; if ((*first)->matching_bits < (*second)->matching_bits) return 1; else return 0; } /** * Select a peer from the routing table that would be a good routing * destination for sending a message for "target". The resulting peer * must not be in the set of blocked peers.

* * Note that we should not ALWAYS select the closest peer to the * target, peers further away from the target should be chosen with * exponentially declining probability. * * @param target the key we are selecting a peer to route to * @param bloom a bloomfilter containing entries this request has seen already * @param hops how many hops has this message traversed thus far * * @return Peer to route to, or NULL on error */ static struct PeerInfo * select_peer (const GNUNET_HashCode * target, struct GNUNET_CONTAINER_BloomFilter *bloom, unsigned int hops) { unsigned int bc; unsigned int i; unsigned int count; unsigned int offset; int closest_bucket; struct PeerInfo *pos; struct PeerInfo *sorted_closest[bucket_size]; unsigned long long temp_converge_distance; unsigned long long total_distance; unsigned long long selected; #if DEBUG_DHT > 1 unsigned long long stats_total_distance; double sum; #endif /* For kademlia */ unsigned int distance; unsigned int largest_distance; struct PeerInfo *chosen; total_distance = 0; /** If we are doing kademlia routing, or converge is binary (saves some cycles) */ if ((strict_kademlia == GNUNET_YES) || ((converge_option == DHT_CONVERGE_BINARY) && (hops >= converge_modifier))) { largest_distance = 0; chosen = NULL; for (bc = lowest_bucket; bc < MAX_BUCKETS; bc++) { pos = k_buckets[bc].head; count = 0; while ((pos != NULL) && (count < bucket_size)) { /* If we are doing strict Kademlia routing, then checking the bloomfilter is basically cheating! */ if (GNUNET_NO == GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)) { distance = inverse_distance (target, &pos->id.hashPubKey); if (distance > largest_distance) { chosen = pos; largest_distance = distance; } } count++; pos = pos->next; } } if ((largest_distance > 0) && (chosen != NULL)) { GNUNET_CONTAINER_bloomfilter_add (bloom, &chosen->id.hashPubKey); return chosen; } else { return NULL; } } /* GNUnet-style */ total_distance = 0; /* Three steps: order peers in closest bucket (most matching bits). * Then go over all LOWER buckets (matching same bits we do) * Then go over all HIGHER buckets (matching less then we do) */ closest_bucket = find_current_bucket (target); GNUNET_assert (closest_bucket >= lowest_bucket); pos = k_buckets[closest_bucket].head; count = 0; offset = 0; /* Need offset as well as count in case peers are bloomfiltered */ memset (sorted_closest, 0, sizeof (sorted_closest)); /* Put any peers in the closest bucket in the sorting array */ while ((pos != NULL) && (count < bucket_size)) { if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)) { count++; pos = pos->next; continue; /* Ignore bloomfiltered peers */ } pos->matching_bits = GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey, target); sorted_closest[offset] = pos; pos = pos->next; offset++; count++; } /* Sort the peers in descending order */ qsort (&sorted_closest[0], offset, sizeof (struct PeerInfo *), &compare_peers); /* Put the sorted closest peers into the possible bins first, in case of overflow. */ for (i = 0; i < offset; i++) { temp_converge_distance = converge_distance (target, sorted_closest[i], hops); if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bloom, &sorted_closest[i]->id. hashPubKey)) break; /* Ignore bloomfiltered peers */ if (total_distance + temp_converge_distance > total_distance) /* Handle largest case and overflow */ total_distance += temp_converge_distance; else break; /* overflow case */ } /* Now handle peers in lower buckets (matches same # of bits as target) */ for (bc = lowest_bucket; bc < closest_bucket; bc++) { pos = k_buckets[bc].head; count = 0; while ((pos != NULL) && (count < bucket_size)) { if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)) { count++; pos = pos->next; continue; /* Ignore bloomfiltered peers */ } temp_converge_distance = converge_distance (target, pos, hops); if (total_distance + temp_converge_distance > total_distance) /* Handle largest case and overflow */ total_distance += temp_converge_distance; else break; /* overflow case */ pos = pos->next; count++; } } /* Now handle all the further away peers */ for (bc = closest_bucket + 1; bc < MAX_BUCKETS; bc++) { pos = k_buckets[bc].head; count = 0; while ((pos != NULL) && (count < bucket_size)) { if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)) { count++; pos = pos->next; continue; /* Ignore bloomfiltered peers */ } temp_converge_distance = converge_distance (target, pos, hops); if (total_distance + temp_converge_distance > total_distance) /* Handle largest case and overflow */ total_distance += temp_converge_distance; else break; /* overflow case */ pos = pos->next; count++; } } if (total_distance == 0) /* No peers to select from! */ { increment_stats ("# failed to select peer"); return NULL; } #if DEBUG_DHT_ROUTING > 1 sum = 0.0; /* PRINT STATS */ /* Put the sorted closest peers into the possible bins first, in case of overflow. */ stats_total_distance = 0; for (i = 0; i < offset; i++) { if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bloom, &sorted_closest[i]->id. hashPubKey)) break; /* Ignore bloomfiltered peers */ temp_converge_distance = converge_distance (target, sorted_closest[i], hops); if (stats_total_distance + temp_converge_distance > stats_total_distance) /* Handle largest case and overflow */ stats_total_distance += temp_converge_distance; else break; /* overflow case */ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Choose %d matching bits (%d bits match me) (%.2f percent) converge ret %llu\n", GNUNET_CRYPTO_hash_matching_bits (&sorted_closest[i]->id. hashPubKey, target), GNUNET_CRYPTO_hash_matching_bits (&sorted_closest[i]->id. hashPubKey, &my_identity.hashPubKey), (temp_converge_distance / (double) total_distance) * 100, temp_converge_distance); } /* Now handle peers in lower buckets (matches same # of bits as target) */ for (bc = lowest_bucket; bc < closest_bucket; bc++) { pos = k_buckets[bc].head; count = 0; while ((pos != NULL) && (count < bucket_size)) { if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)) { count++; pos = pos->next; continue; /* Ignore bloomfiltered peers */ } temp_converge_distance = converge_distance (target, pos, hops); if (stats_total_distance + temp_converge_distance > stats_total_distance) /* Handle largest case and overflow */ stats_total_distance += temp_converge_distance; else break; /* overflow case */ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Choose %d matching bits (%d bits match me) (%.2f percent) converge ret %llu\n", GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey, target), GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey, &my_identity. hashPubKey), (temp_converge_distance / (double) total_distance) * 100, temp_converge_distance); pos = pos->next; count++; } } /* Now handle all the further away peers */ for (bc = closest_bucket + 1; bc < MAX_BUCKETS; bc++) { pos = k_buckets[bc].head; count = 0; while ((pos != NULL) && (count < bucket_size)) { if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)) { count++; pos = pos->next; continue; /* Ignore bloomfiltered peers */ } temp_converge_distance = converge_distance (target, pos, hops); if (stats_total_distance + temp_converge_distance > stats_total_distance) /* Handle largest case and overflow */ stats_total_distance += temp_converge_distance; else break; /* overflow case */ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Choose %d matching bits (%d bits match me) (%.2f percent) converge ret %llu\n", GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey, target), GNUNET_CRYPTO_hash_matching_bits (&pos->id.hashPubKey, &my_identity. hashPubKey), (temp_converge_distance / (double) total_distance) * 100, temp_converge_distance); pos = pos->next; count++; } } /* END PRINT STATS */ #endif /* Now actually choose a peer */ selected = GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK, total_distance); /* Go over closest sorted peers. */ for (i = 0; i < offset; i++) { if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bloom, &sorted_closest[i]->id. hashPubKey)) break; /* Ignore bloomfiltered peers */ temp_converge_distance = converge_distance (target, sorted_closest[i], hops); if (temp_converge_distance >= selected) return sorted_closest[i]; else selected -= temp_converge_distance; } /* Now handle peers in lower buckets (matches same # of bits as target) */ for (bc = lowest_bucket; bc < closest_bucket; bc++) { pos = k_buckets[bc].head; count = 0; while ((pos != NULL) && (count < bucket_size)) { if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)) { count++; pos = pos->next; continue; /* Ignore bloomfiltered peers */ } temp_converge_distance = converge_distance (target, pos, hops); if (temp_converge_distance >= selected) return pos; else selected -= temp_converge_distance; pos = pos->next; count++; } } /* Now handle all the further away peers */ for (bc = closest_bucket + 1; bc < MAX_BUCKETS; bc++) { pos = k_buckets[bc].head; count = 0; while ((pos != NULL) && (count < bucket_size)) { if (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bloom, &pos->id.hashPubKey)) { count++; pos = pos->next; continue; /* Ignore bloomfiltered peers */ } temp_converge_distance = converge_distance (target, pos, hops); if (temp_converge_distance >= selected) return pos; else selected -= temp_converge_distance; pos = pos->next; count++; } } increment_stats ("# failed to select peer"); return NULL; } /** * Task used to remove recent entries, either * after timeout, when full, or on shutdown. * * @param cls the entry to remove * @param tc context, reason, etc. */ static void remove_recent (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct RecentRequest *req = cls; static GNUNET_HashCode hash; GNUNET_assert (req != NULL); hash_from_uid (req->uid, &hash); GNUNET_assert (GNUNET_YES == GNUNET_CONTAINER_multihashmap_remove (recent.hashmap, &hash, req)); GNUNET_CONTAINER_heap_remove_node (req->heap_node); GNUNET_CONTAINER_bloomfilter_free (req->bloom); GNUNET_free (req); /* if ( (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0) && (0 == GNUNET_CONTAINER_multihashmap_size(recent.hashmap)) && (0 == GNUNET_CONTAINER_heap_get_size(recent.minHeap))) { GNUNET_CONTAINER_multihashmap_destroy(recent.hashmap); GNUNET_CONTAINER_heap_destroy(recent.minHeap); } */ } /** * Remember this routing request so that if a reply is * received we can either forward it to the correct peer * or return the result locally. * * @param msg_ctx Context of the route request * * @return GNUNET_YES if this response was cached, GNUNET_NO if not */ static int cache_response (struct DHT_MessageContext *msg_ctx) { struct DHTQueryRecord *record; struct DHTRouteSource *source_info; struct DHTRouteSource *pos; struct GNUNET_TIME_Absolute now; unsigned int current_size; current_size = GNUNET_CONTAINER_multihashmap_size (forward_list.hashmap); #if DELETE_WHEN_FULL while (current_size >= MAX_OUTSTANDING_FORWARDS) { source_info = GNUNET_CONTAINER_heap_remove_root (forward_list.minHeap); GNUNET_assert (source_info != NULL); record = source_info->record; GNUNET_CONTAINER_DLL_remove (record->head, record->tail, source_info); if (record->head == NULL) /* No more entries in DLL */ { GNUNET_assert (GNUNET_YES == GNUNET_CONTAINER_multihashmap_remove (forward_list.hashmap, &record->key, record)); GNUNET_free (record); } if (source_info->delete_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (source_info->delete_task); source_info->delete_task = GNUNET_SCHEDULER_NO_TASK; } if (source_info->find_peers_responded != NULL) GNUNET_CONTAINER_bloomfilter_free (source_info->find_peers_responded); GNUNET_free (source_info); current_size = GNUNET_CONTAINER_multihashmap_size (forward_list.hashmap); } #endif /** Non-local request and have too many outstanding forwards, discard! */ if ((current_size >= MAX_OUTSTANDING_FORWARDS) && (msg_ctx->client == NULL)) return GNUNET_NO; now = GNUNET_TIME_absolute_get (); record = GNUNET_CONTAINER_multihashmap_get (forward_list.hashmap, &msg_ctx->key); if (record != NULL) /* Already know this request! */ { pos = record->head; while (pos != NULL) { if (0 == memcmp (msg_ctx->peer, &pos->source, sizeof (struct GNUNET_PeerIdentity))) break; /* Already have this peer in reply list! */ pos = pos->next; } if ((pos != NULL) && (pos->client == msg_ctx->client)) /* Seen this already */ { GNUNET_CONTAINER_heap_update_cost (forward_list.minHeap, pos->hnode, now.abs_value); return GNUNET_NO; } } else { record = GNUNET_malloc (sizeof (struct DHTQueryRecord)); GNUNET_assert (GNUNET_OK == GNUNET_CONTAINER_multihashmap_put (forward_list.hashmap, &msg_ctx->key, record, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY)); memcpy (&record->key, &msg_ctx->key, sizeof (GNUNET_HashCode)); } source_info = GNUNET_malloc (sizeof (struct DHTRouteSource)); source_info->record = record; source_info->delete_task = GNUNET_SCHEDULER_add_delayed (DHT_FORWARD_TIMEOUT, &remove_forward_entry, source_info); source_info->find_peers_responded = GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K); memcpy (&source_info->source, msg_ctx->peer, sizeof (struct GNUNET_PeerIdentity)); GNUNET_CONTAINER_DLL_insert_after (record->head, record->tail, record->tail, source_info); if (msg_ctx->client != NULL) /* For local request, set timeout so high it effectively never gets pushed out */ { source_info->client = msg_ctx->client; now = GNUNET_TIME_absolute_get_forever (); } source_info->hnode = GNUNET_CONTAINER_heap_insert (forward_list.minHeap, source_info, now.abs_value); #if DEBUG_DHT > 1 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Created new forward source info for %s uid %llu\n", my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key), msg_ctx->unique_id); #endif return GNUNET_YES; } /** * Main function that handles whether or not to route a message to other * peers. * * @param msg the message to be routed * @param msg_ctx the context containing all pertinent information about the message */ static void route_message (const struct GNUNET_MessageHeader *msg, struct DHT_MessageContext *msg_ctx) { int i; struct PeerInfo *selected; #if DEBUG_DHT_ROUTING > 1 struct PeerInfo *nearest; #endif unsigned int target_forward_count; unsigned int forward_count; struct RecentRequest *recent_req; GNUNET_HashCode unique_hash; char *stat_forward_count; char *temp_stat_str; #if DEBUG_DHT_ROUTING int ret; #endif if (malicious_dropper == GNUNET_YES) { #if DEBUG_DHT_ROUTING if ((debug_routes_extended) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE, msg_ctx->hop_count, GNUNET_SYSERR, &my_identity, &msg_ctx->key, msg_ctx->peer, NULL); } #endif if (msg_ctx->bloom != NULL) { GNUNET_CONTAINER_bloomfilter_free (msg_ctx->bloom); msg_ctx->bloom = NULL; } return; } increment_stats (STAT_ROUTES); target_forward_count = get_forward_count (msg_ctx->hop_count, msg_ctx->replication); GNUNET_asprintf (&stat_forward_count, "# forward counts of %d", target_forward_count); increment_stats (stat_forward_count); GNUNET_free (stat_forward_count); if (msg_ctx->bloom == NULL) msg_ctx->bloom = GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K); if ((stop_on_closest == GNUNET_YES) && (msg_ctx->closest == GNUNET_YES) && (ntohs (msg->type) == GNUNET_MESSAGE_TYPE_DHT_PUT)) target_forward_count = 0; /** * NOTICE: In Kademlia, a find peer request goes no further if the peer doesn't return * any closer peers (which is being checked for below). Since we are doing recursive * routing we have no choice but to stop forwarding in this case. This means that at * any given step the request may NOT be forwarded to alpha peers (because routes will * stop and the parallel route will not be aware of it). Of course, assuming that we * have fulfilled the Kademlia requirements for routing table fullness this will never * ever ever be a problem. * * However, is this fair? * * Since we use these requests to build our routing tables (and we build them in the * testing driver) we will ignore this restriction for FIND_PEER messages so that * routing tables still get constructed. */ if ((GNUNET_YES == strict_kademlia) && (msg_ctx->closest == GNUNET_YES) && (msg_ctx->hop_count > 0) && (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_DHT_FIND_PEER)) target_forward_count = 0; GNUNET_CONTAINER_bloomfilter_add (msg_ctx->bloom, &my_identity.hashPubKey); hash_from_uid (msg_ctx->unique_id, &unique_hash); if (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains (recent.hashmap, &unique_hash)) { recent_req = GNUNET_CONTAINER_multihashmap_get (recent.hashmap, &unique_hash); GNUNET_assert (recent_req != NULL); if (0 != memcmp (&recent_req->key, &msg_ctx->key, sizeof (GNUNET_HashCode))) increment_stats (STAT_DUPLICATE_UID); else { increment_stats (STAT_RECENT_SEEN); GNUNET_CONTAINER_bloomfilter_or2 (msg_ctx->bloom, recent_req->bloom, DHT_BLOOM_SIZE); } } else { recent_req = GNUNET_malloc (sizeof (struct RecentRequest)); recent_req->uid = msg_ctx->unique_id; memcpy (&recent_req->key, &msg_ctx->key, sizeof (GNUNET_HashCode)); recent_req->remove_task = GNUNET_SCHEDULER_add_delayed (DEFAULT_RECENT_REMOVAL, &remove_recent, recent_req); recent_req->heap_node = GNUNET_CONTAINER_heap_insert (recent.minHeap, recent_req, GNUNET_TIME_absolute_get ().abs_value); recent_req->bloom = GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K); GNUNET_CONTAINER_multihashmap_put (recent.hashmap, &unique_hash, recent_req, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY); } if (GNUNET_CONTAINER_multihashmap_size (recent.hashmap) > DHT_MAX_RECENT) { recent_req = GNUNET_CONTAINER_heap_peek (recent.minHeap); GNUNET_assert (recent_req != NULL); GNUNET_SCHEDULER_cancel (recent_req->remove_task); GNUNET_SCHEDULER_add_now (&remove_recent, recent_req); } forward_count = 0; for (i = 0; i < target_forward_count; i++) { selected = select_peer (&msg_ctx->key, msg_ctx->bloom, msg_ctx->hop_count); if (selected != NULL) { forward_count++; if (GNUNET_CRYPTO_hash_matching_bits (&selected->id.hashPubKey, &msg_ctx->key) >= GNUNET_CRYPTO_hash_matching_bits (&my_identity.hashPubKey, &msg_ctx->key)) GNUNET_asprintf (&temp_stat_str, "# requests routed to close(r) peer hop %u", msg_ctx->hop_count); else GNUNET_asprintf (&temp_stat_str, "# requests routed to less close peer hop %u", msg_ctx->hop_count); if (temp_stat_str != NULL) { increment_stats (temp_stat_str); GNUNET_free (temp_stat_str); } GNUNET_CONTAINER_bloomfilter_add (msg_ctx->bloom, &selected->id.hashPubKey); #if DEBUG_DHT_ROUTING > 1 nearest = find_closest_peer (&msg_ctx->key); nearest_buf = GNUNET_strdup (GNUNET_i2s (&nearest->id)); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Forwarding request key %s uid %llu to peer %s (closest %s, bits %d, distance %u)\n", my_short_id, "DHT", GNUNET_h2s (&msg_ctx->key), msg_ctx->unique_id, GNUNET_i2s (&selected->id), nearest_buf, GNUNET_CRYPTO_hash_matching_bits (&nearest->id. hashPubKey, msg_ctx->key), distance (&nearest->id.hashPubKey, msg_ctx->key)); GNUNET_free (nearest_buf); #endif #if DEBUG_DHT_ROUTING if ((debug_routes_extended) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE, msg_ctx->hop_count, GNUNET_NO, &my_identity, &msg_ctx->key, msg_ctx->peer, &selected->id); } #endif forward_message (msg, selected, msg_ctx); } } if (msg_ctx->bloom != NULL) { GNUNET_CONTAINER_bloomfilter_or2 (recent_req->bloom, msg_ctx->bloom, DHT_BLOOM_SIZE); GNUNET_CONTAINER_bloomfilter_free (msg_ctx->bloom); msg_ctx->bloom = NULL; } #if DEBUG_DHT_ROUTING if (forward_count == 0) ret = GNUNET_SYSERR; else ret = GNUNET_NO; if ((debug_routes_extended) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_route (NULL, msg_ctx->unique_id, DHTLOG_ROUTE, msg_ctx->hop_count, ret, &my_identity, &msg_ctx->key, msg_ctx->peer, NULL); } #endif } /** * Main function that handles whether or not to route a message to other * peers. * * @param msg the message to be routed * @param msg_ctx the context containing all pertinent information about the message */ static void demultiplex_message (const struct GNUNET_MessageHeader *msg, struct DHT_MessageContext *msg_ctx) { /* FIXME: Should we use closest excluding those we won't route to (the bloomfilter problem)? */ msg_ctx->closest = am_closest_peer (&msg_ctx->key, msg_ctx->bloom); switch (ntohs (msg->type)) { case GNUNET_MESSAGE_TYPE_DHT_GET: /* Add to hashmap of requests seen, search for data (always) */ cache_response (msg_ctx); handle_dht_get (msg, msg_ctx); break; case GNUNET_MESSAGE_TYPE_DHT_PUT: /* Check if closest, if so insert data. */ increment_stats (STAT_PUTS); handle_dht_put (msg, msg_ctx); break; case GNUNET_MESSAGE_TYPE_DHT_FIND_PEER: /* Check if closest and not started by us, check options, add to requests seen */ increment_stats (STAT_FIND_PEER); if (((msg_ctx->hop_count > 0) && (0 != memcmp (msg_ctx->peer, &my_identity, sizeof (struct GNUNET_PeerIdentity)))) || (msg_ctx->client != NULL)) { cache_response (msg_ctx); if ((msg_ctx->closest == GNUNET_YES) || (msg_ctx->msg_options == GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE)) handle_dht_find_peer (msg, msg_ctx); } else route_message (msg, msg_ctx); #if DEBUG_DHT_ROUTING if (msg_ctx->hop_count == 0) /* Locally initiated request */ { if ((debug_routes) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_dhtkey (NULL, &msg_ctx->key); dhtlog_handle->insert_query (NULL, msg_ctx->unique_id, DHTLOG_FIND_PEER, msg_ctx->hop_count, GNUNET_NO, &my_identity, &msg_ctx->key); } } #endif break; default: GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "`%s': Message type (%d) not handled, forwarding anyway!\n", "DHT", ntohs (msg->type)); route_message (msg, msg_ctx); } } /** * Iterator for local get request results, * * @param cls closure for iterator, NULL * @param exp when does this value expire? * @param key the key this data is stored under * @param size the size of the data identified by key * @param data the actual data * @param type the type of the data * * @return GNUNET_OK to continue iteration, anything else * to stop iteration. */ static int republish_content_iterator (void *cls, struct GNUNET_TIME_Absolute exp, const GNUNET_HashCode * key, size_t size, const char *data, uint32_t type) { struct DHT_MessageContext *new_msg_ctx; struct GNUNET_DHT_PutMessage *put_msg; #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Received `%s' response from datacache\n", my_short_id, "DHT", "GET"); #endif new_msg_ctx = GNUNET_malloc (sizeof (struct DHT_MessageContext)); put_msg = GNUNET_malloc (sizeof (struct GNUNET_DHT_PutMessage) + size); put_msg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_PUT); put_msg->header.size = htons (sizeof (struct GNUNET_DHT_PutMessage) + size); put_msg->expiration = GNUNET_TIME_absolute_hton (exp); put_msg->type = htons (type); memcpy (&put_msg[1], data, size); new_msg_ctx->unique_id = GNUNET_ntohll (GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK, UINT64_MAX)); new_msg_ctx->replication = ntohl (DEFAULT_PUT_REPLICATION); new_msg_ctx->msg_options = ntohl (0); new_msg_ctx->network_size = estimate_diameter (); new_msg_ctx->peer = &my_identity; new_msg_ctx->bloom = GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K); new_msg_ctx->hop_count = 0; new_msg_ctx->importance = DHT_DEFAULT_P2P_IMPORTANCE; new_msg_ctx->timeout = DHT_DEFAULT_P2P_TIMEOUT; increment_stats (STAT_PUT_START); demultiplex_message (&put_msg->header, new_msg_ctx); GNUNET_free (new_msg_ctx); GNUNET_free (put_msg); return GNUNET_OK; } /** * Task used to republish data. * * @param cls closure (a struct RepublishContext) * @param tc runtime context for this task */ static void republish_content (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct RepublishContext *put_context = cls; unsigned int results; if ( (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0) { GNUNET_free (put_context); return; } GNUNET_assert (datacache != NULL); /* If we have no datacache we never should have scheduled this! */ results = GNUNET_DATACACHE_get (datacache, &put_context->key, put_context->type, &republish_content_iterator, NULL); if (results == 0) /* Data must have expired */ GNUNET_free (put_context); else /* Reschedule task for next time period */ GNUNET_SCHEDULER_add_delayed (dht_republish_frequency, &republish_content, put_context); } /** * Iterator over hash map entries. * * @param cls client to search for in source routes * @param key current key code (ignored) * @param value value in the hash map, a DHTQueryRecord * @return GNUNET_YES if we should continue to * iterate, * GNUNET_NO if not. */ static int find_client_records (void *cls, const GNUNET_HashCode * key, void *value) { struct ClientList *client = cls; struct DHTQueryRecord *record = value; struct DHTRouteSource *pos; pos = record->head; while (pos != NULL) { if (pos->client == client) break; pos = pos->next; } if (pos != NULL) { GNUNET_CONTAINER_DLL_remove (record->head, record->tail, pos); GNUNET_CONTAINER_heap_remove_node (pos->hnode); if (pos->delete_task != GNUNET_SCHEDULER_NO_TASK) { GNUNET_SCHEDULER_cancel (pos->delete_task); pos->delete_task = GNUNET_SCHEDULER_NO_TASK; } if (pos->find_peers_responded != NULL) GNUNET_CONTAINER_bloomfilter_free (pos->find_peers_responded); GNUNET_free (pos); } if (record->head == NULL) /* No more entries in DLL */ { GNUNET_assert (GNUNET_YES == GNUNET_CONTAINER_multihashmap_remove (forward_list.hashmap, &record->key, record)); GNUNET_free (record); } return GNUNET_YES; } /** * Functions with this signature are called whenever a client * is disconnected on the network level. * * @param cls closure (NULL for dht) * @param client identification of the client; NULL * for the last call when the server is destroyed */ static void handle_client_disconnect (void *cls, struct GNUNET_SERVER_Client *client) { struct ClientList *pos = client_list; struct ClientList *prev; struct ClientList *found; struct PendingMessage *reply; prev = NULL; found = NULL; while (pos != NULL) { if (pos->client_handle == client) { if (prev != NULL) prev->next = pos->next; else client_list = pos->next; found = pos; break; } prev = pos; pos = pos->next; } if (found != NULL) { if (found->transmit_handle != NULL) GNUNET_CONNECTION_notify_transmit_ready_cancel (found->transmit_handle); while (NULL != (reply = found->pending_head)) { GNUNET_CONTAINER_DLL_remove (found->pending_head, found->pending_tail, reply); GNUNET_free (reply); } GNUNET_CONTAINER_multihashmap_iterate (forward_list.hashmap, &find_client_records, found); GNUNET_free (found); } } /** * Find a client if it exists, add it otherwise. * * @param client the server handle to the client * * @return the client if found, a new client otherwise */ static struct ClientList * find_active_client (struct GNUNET_SERVER_Client *client) { struct ClientList *pos = client_list; struct ClientList *ret; while (pos != NULL) { if (pos->client_handle == client) return pos; pos = pos->next; } ret = GNUNET_malloc (sizeof (struct ClientList)); ret->client_handle = client; ret->next = client_list; client_list = ret; return ret; } #if HAVE_MALICIOUS /** * Task to send a malicious put message across the network. * * @param cls closure for this task * @param tc the context under which the task is running */ static void malicious_put_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { static struct GNUNET_DHT_PutMessage put_message; static struct DHT_MessageContext msg_ctx; static GNUNET_HashCode key; uint32_t random_key; if ( (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0) return; put_message.header.size = htons (sizeof (struct GNUNET_DHT_PutMessage)); put_message.header.type = htons (GNUNET_MESSAGE_TYPE_DHT_PUT); put_message.type = htonl (GNUNET_BLOCK_DHT_MALICIOUS_MESSAGE_TYPE); put_message.expiration = GNUNET_TIME_absolute_hton (GNUNET_TIME_absolute_get_forever ()); memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext)); random_key = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, UINT32_MAX); GNUNET_CRYPTO_hash (&random_key, sizeof (uint32_t), &key); memcpy (&msg_ctx.key, &key, sizeof (GNUNET_HashCode)); msg_ctx.unique_id = GNUNET_ntohll (GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK, UINT64_MAX)); msg_ctx.replication = ntohl (DHT_DEFAULT_FIND_PEER_REPLICATION); msg_ctx.msg_options = ntohl (0); msg_ctx.network_size = estimate_diameter (); msg_ctx.peer = &my_identity; msg_ctx.importance = DHT_DEFAULT_P2P_IMPORTANCE; msg_ctx.timeout = DHT_DEFAULT_P2P_TIMEOUT; #if DEBUG_DHT_ROUTING if (dhtlog_handle != NULL) dhtlog_handle->insert_dhtkey (NULL, &key); #endif increment_stats (STAT_PUT_START); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Sending malicious PUT message with hash %s\n", my_short_id, "DHT", GNUNET_h2s (&key)); demultiplex_message (&put_message.header, &msg_ctx); GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, malicious_put_frequency), &malicious_put_task, NULL); } /** * Task to send a malicious put message across the network. * * @param cls closure for this task * @param tc the context under which the task is running */ static void malicious_get_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { static struct GNUNET_DHT_GetMessage get_message; struct DHT_MessageContext msg_ctx; static GNUNET_HashCode key; uint32_t random_key; if ( (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0) return; get_message.header.size = htons (sizeof (struct GNUNET_DHT_GetMessage)); get_message.header.type = htons (GNUNET_MESSAGE_TYPE_DHT_GET); get_message.type = htonl (GNUNET_BLOCK_DHT_MALICIOUS_MESSAGE_TYPE); memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext)); random_key = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, UINT32_MAX); GNUNET_CRYPTO_hash (&random_key, sizeof (uint32_t), &key); memcpy (&msg_ctx.key, &key, sizeof (GNUNET_HashCode)); msg_ctx.unique_id = GNUNET_ntohll (GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK, UINT64_MAX)); msg_ctx.replication = ntohl (DHT_DEFAULT_FIND_PEER_REPLICATION); msg_ctx.msg_options = ntohl (0); msg_ctx.network_size = estimate_diameter (); msg_ctx.peer = &my_identity; msg_ctx.importance = DHT_DEFAULT_P2P_IMPORTANCE; msg_ctx.timeout = DHT_DEFAULT_P2P_TIMEOUT; #if DEBUG_DHT_ROUTING if (dhtlog_handle != NULL) dhtlog_handle->insert_dhtkey (NULL, &key); #endif increment_stats (STAT_GET_START); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Sending malicious GET message with hash %s\n", my_short_id, "DHT", GNUNET_h2s (&key)); demultiplex_message (&get_message.header, &msg_ctx); GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, malicious_get_frequency), &malicious_get_task, NULL); } #endif /** * Iterator over hash map entries. * * @param cls closure * @param key current key code * @param value value in the hash map * @return GNUNET_YES if we should continue to * iterate, * GNUNET_NO if not. */ static int add_known_to_bloom (void *cls, const GNUNET_HashCode * key, void *value) { struct GNUNET_CONTAINER_BloomFilter *bloom = cls; GNUNET_CONTAINER_bloomfilter_add (bloom, key); return GNUNET_YES; } /** * Task to send a find peer message for our own peer identifier * so that we can find the closest peers in the network to ourselves * and attempt to connect to them. * * @param cls closure for this task * @param tc the context under which the task is running */ static void send_find_peer_message (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct GNUNET_DHT_FindPeerMessage *find_peer_msg; struct DHT_MessageContext msg_ctx; struct GNUNET_TIME_Relative next_send_time; struct GNUNET_CONTAINER_BloomFilter *temp_bloom; #if COUNT_INTERVAL struct GNUNET_TIME_Relative time_diff; struct GNUNET_TIME_Absolute end; double multiplier; double count_per_interval; #endif if ( (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0) return; 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! */ { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Have %d newly found peers since last find peer message sent!\n", newly_found_peers); GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES, &send_find_peer_message, NULL); newly_found_peers = 0; return; } increment_stats (STAT_FIND_PEER_START); #if COUNT_INTERVAL end = GNUNET_TIME_absolute_get (); time_diff = GNUNET_TIME_absolute_get_difference (find_peer_context.start, end); if (time_diff.abs_value > FIND_PEER_CALC_INTERVAL.abs_value) { multiplier = time_diff.abs_value / FIND_PEER_CALC_INTERVAL.abs_value; count_per_interval = find_peer_context.count / multiplier; } else { multiplier = FIND_PEER_CALC_INTERVAL.abs_value / time_diff.abs_value; count_per_interval = find_peer_context.count * multiplier; } #endif #if FIND_PEER_WITH_HELLO find_peer_msg = GNUNET_malloc (sizeof (struct GNUNET_DHT_FindPeerMessage) + GNUNET_HELLO_size ((struct GNUNET_HELLO_Message *) my_hello)); find_peer_msg->header.size = htons (sizeof (struct GNUNET_DHT_FindPeerMessage) + GNUNET_HELLO_size ((struct GNUNET_HELLO_Message *) my_hello)); memcpy (&find_peer_msg[1], my_hello, GNUNET_HELLO_size ((struct GNUNET_HELLO_Message *) my_hello)); #else find_peer_msg = GNUNET_malloc (sizeof (struct GNUNET_DHT_FindPeerMessage)); find_peer_msg->header.size = htons (sizeof (struct GNUNET_DHT_FindPeerMessage)); #endif find_peer_msg->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_FIND_PEER); temp_bloom = GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE, DHT_BLOOM_K); GNUNET_CONTAINER_multihashmap_iterate (all_known_peers, &add_known_to_bloom, temp_bloom); GNUNET_assert (GNUNET_OK == GNUNET_CONTAINER_bloomfilter_get_raw_data (temp_bloom, find_peer_msg-> bloomfilter, DHT_BLOOM_SIZE)); GNUNET_CONTAINER_bloomfilter_free (temp_bloom); memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext)); memcpy (&msg_ctx.key, &my_identity.hashPubKey, sizeof (GNUNET_HashCode)); msg_ctx.unique_id = GNUNET_ntohll (GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_STRONG, UINT64_MAX)); msg_ctx.replication = DHT_DEFAULT_FIND_PEER_REPLICATION; msg_ctx.msg_options = DHT_DEFAULT_FIND_PEER_OPTIONS; msg_ctx.network_size = estimate_diameter (); msg_ctx.peer = &my_identity; msg_ctx.importance = DHT_DEFAULT_FIND_PEER_IMPORTANCE; msg_ctx.timeout = DHT_DEFAULT_FIND_PEER_TIMEOUT; demultiplex_message (&find_peer_msg->header, &msg_ctx); GNUNET_free (find_peer_msg); GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Sent `%s' request to some (?) peers\n", my_short_id, "DHT", "FIND PEER"); if (newly_found_peers < bucket_size) { next_send_time.rel_value = (DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value / 2) + GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_STRONG, DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value / 2); } else { next_send_time.rel_value = DHT_MINIMUM_FIND_PEER_INTERVAL.rel_value + GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_STRONG, DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value - DHT_MINIMUM_FIND_PEER_INTERVAL.rel_value); } GNUNET_assert (next_send_time.rel_value != 0); find_peer_context.count = 0; newly_found_peers = 0; find_peer_context.start = GNUNET_TIME_absolute_get (); if (GNUNET_YES == do_find_peer) { GNUNET_SCHEDULER_add_delayed (next_send_time, &send_find_peer_message, NULL); } } /** * Handler for any generic DHT messages, calls the appropriate handler * depending on message type, sends confirmation if responses aren't otherwise * expected. * * @param cls closure for the service * @param client the client we received this message from * @param message the actual message received */ static void handle_dht_local_route_request (void *cls, struct GNUNET_SERVER_Client *client, const struct GNUNET_MessageHeader *message) { const struct GNUNET_DHT_RouteMessage *dht_msg = (const struct GNUNET_DHT_RouteMessage *) message; const struct GNUNET_MessageHeader *enc_msg; struct DHT_MessageContext msg_ctx; enc_msg = (const struct GNUNET_MessageHeader *) &dht_msg[1]; #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Received `%s' request from client, message type %d, key %s, uid %llu\n", my_short_id, "DHT", "GENERIC", ntohs (message->type), GNUNET_h2s (&dht_msg->key), GNUNET_ntohll (dht_msg->unique_id)); #endif #if DEBUG_DHT_ROUTING if (dhtlog_handle != NULL) dhtlog_handle->insert_dhtkey (NULL, &dht_msg->key); #endif memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext)); msg_ctx.client = find_active_client (client); memcpy (&msg_ctx.key, &dht_msg->key, sizeof (GNUNET_HashCode)); msg_ctx.unique_id = GNUNET_ntohll (dht_msg->unique_id); msg_ctx.replication = ntohl (dht_msg->desired_replication_level); msg_ctx.msg_options = ntohl (dht_msg->options); if (GNUNET_DHT_RO_RECORD_ROUTE == (msg_ctx.msg_options & GNUNET_DHT_RO_RECORD_ROUTE)) { msg_ctx.path_history = GNUNET_malloc(sizeof(struct GNUNET_PeerIdentity)); memcpy(msg_ctx.path_history, &my_identity, sizeof(struct GNUNET_PeerIdentity)); msg_ctx.path_history_len = 1; } msg_ctx.network_size = estimate_diameter (); msg_ctx.peer = &my_identity; msg_ctx.importance = DHT_DEFAULT_P2P_IMPORTANCE + 4; /* Make local routing a higher priority */ msg_ctx.timeout = DHT_DEFAULT_P2P_TIMEOUT; if (ntohs (enc_msg->type) == GNUNET_MESSAGE_TYPE_DHT_GET) increment_stats (STAT_GET_START); else if (ntohs (enc_msg->type) == GNUNET_MESSAGE_TYPE_DHT_PUT) increment_stats (STAT_PUT_START); else if (ntohs (enc_msg->type) == GNUNET_MESSAGE_TYPE_DHT_FIND_PEER) increment_stats (STAT_FIND_PEER_START); if (GNUNET_YES == malicious_dropper) { if (ntohs (enc_msg->type) == GNUNET_MESSAGE_TYPE_DHT_GET) { #if DEBUG_DHT_ROUTING if ((debug_routes) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_query (NULL, msg_ctx.unique_id, DHTLOG_GET, msg_ctx.hop_count, GNUNET_NO, &my_identity, &msg_ctx.key); } #endif } else if (ntohs (enc_msg->type) == GNUNET_MESSAGE_TYPE_DHT_PUT) { #if DEBUG_DHT_ROUTING if ((debug_routes) && (dhtlog_handle != NULL)) { dhtlog_handle->insert_query (NULL, msg_ctx.unique_id, DHTLOG_PUT, msg_ctx.hop_count, GNUNET_NO, &my_identity, &msg_ctx.key); } #endif } GNUNET_SERVER_receive_done (client, GNUNET_OK); GNUNET_free_non_null(msg_ctx.path_history); return; } demultiplex_message (enc_msg, &msg_ctx); GNUNET_SERVER_receive_done (client, GNUNET_OK); } /** * Handler for any locally received DHT control messages, * sets malicious flags mostly for now. * * @param cls closure for the service * @param client the client we received this message from * @param message the actual message received * */ static void handle_dht_control_message (void *cls, struct GNUNET_SERVER_Client *client, const struct GNUNET_MessageHeader *message) { const struct GNUNET_DHT_ControlMessage *dht_control_msg = (const struct GNUNET_DHT_ControlMessage *) message; #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Received `%s' request from client, command %d\n", my_short_id, "DHT", "CONTROL", ntohs (dht_control_msg->command)); #endif switch (ntohs (dht_control_msg->command)) { case GNUNET_MESSAGE_TYPE_DHT_FIND_PEER: GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sending self seeking find peer request!\n"); GNUNET_SCHEDULER_add_now (&send_find_peer_message, NULL); break; #if HAVE_MALICIOUS case GNUNET_MESSAGE_TYPE_DHT_MALICIOUS_GET: if (ntohs (dht_control_msg->variable) > 0) malicious_get_frequency = ntohs (dht_control_msg->variable); if (malicious_get_frequency == 0) malicious_get_frequency = DEFAULT_MALICIOUS_GET_FREQUENCY; if (malicious_getter != GNUNET_YES) GNUNET_SCHEDULER_add_now (&malicious_get_task, NULL); malicious_getter = GNUNET_YES; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Initiating malicious GET behavior, frequency %d\n", my_short_id, "DHT", malicious_get_frequency); break; case GNUNET_MESSAGE_TYPE_DHT_MALICIOUS_PUT: if (ntohs (dht_control_msg->variable) > 0) malicious_put_frequency = ntohs (dht_control_msg->variable); if (malicious_put_frequency == 0) malicious_put_frequency = DEFAULT_MALICIOUS_PUT_FREQUENCY; if (malicious_putter != GNUNET_YES) GNUNET_SCHEDULER_add_now (&malicious_put_task, NULL); malicious_putter = GNUNET_YES; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Initiating malicious PUT behavior, frequency %d\n", my_short_id, "DHT", malicious_put_frequency); break; case GNUNET_MESSAGE_TYPE_DHT_MALICIOUS_DROP: #if DEBUG_DHT_ROUTING if ((malicious_dropper != GNUNET_YES) && (dhtlog_handle != NULL)) dhtlog_handle->set_malicious (&my_identity); #endif malicious_dropper = GNUNET_YES; GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Initiating malicious DROP behavior\n", my_short_id, "DHT"); break; #endif default: GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "%s:%s Unknown control command type `%d'!\n", my_short_id, "DHT", ntohs (dht_control_msg->command)); break; } GNUNET_SERVER_receive_done (client, GNUNET_OK); } /** * Handler for any generic DHT stop messages, calls the appropriate handler * depending on message type (if processed locally) * * @param cls closure for the service * @param client the client we received this message from * @param message the actual message received * */ static void handle_dht_local_route_stop (void *cls, struct GNUNET_SERVER_Client *client, const struct GNUNET_MessageHeader *message) { const struct GNUNET_DHT_StopMessage *dht_stop_msg = (const struct GNUNET_DHT_StopMessage *) message; struct DHTQueryRecord *record; struct DHTRouteSource *pos; #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Received `%s' request from client, uid %llu\n", my_short_id, "DHT", "GENERIC STOP", GNUNET_ntohll (dht_stop_msg->unique_id)); #endif record = GNUNET_CONTAINER_multihashmap_get (forward_list.hashmap, &dht_stop_msg->key); if (record != NULL) { pos = record->head; while (pos != NULL) { /* If the client is non-null (local request) and the client matches the requesting client, remove the entry. */ if ((pos->client != NULL) && (pos->client->client_handle == client)) { if (pos->delete_task != GNUNET_SCHEDULER_NO_TASK) GNUNET_SCHEDULER_cancel (pos->delete_task); pos->delete_task = GNUNET_SCHEDULER_add_now (&remove_forward_entry, pos); } pos = pos->next; } } GNUNET_SERVER_receive_done (client, GNUNET_OK); } /** * Core handler for p2p route requests. * * @param cls closure * @param message message * @param peer peer identity this notification is about * @param atsi performance data * */ static int handle_dht_p2p_route_request (void *cls, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_MessageHeader *message, const struct GNUNET_TRANSPORT_ATS_Information *atsi) { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Received P2P request from peer %s\n", my_short_id, "DHT", GNUNET_i2s (peer)); #endif struct GNUNET_DHT_P2PRouteMessage *incoming = (struct GNUNET_DHT_P2PRouteMessage *) message; struct GNUNET_MessageHeader *enc_msg = (struct GNUNET_MessageHeader *) &incoming[1]; struct DHT_MessageContext *msg_ctx; char *route_path; int path_size; if (ntohs (enc_msg->type) == GNUNET_MESSAGE_TYPE_DHT_P2P_PING) /* Throw these away. FIXME: Don't throw these away? (reply) */ { #if DEBUG_PING GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Received P2P Ping message.\n", my_short_id, "DHT"); #endif return GNUNET_YES; } if (ntohs (enc_msg->size) >= GNUNET_SERVER_MAX_MESSAGE_SIZE - 1) { GNUNET_break_op (0); return GNUNET_YES; } if (malicious_dropper == GNUNET_YES) { #if DEBUG_DHT_ROUTING if ((debug_routes_extended) && (dhtlog_handle != NULL)) { /** Log routes that die due to high load! */ dhtlog_handle->insert_route (NULL, GNUNET_ntohll (incoming->unique_id), DHTLOG_ROUTE, ntohl (incoming->hop_count), GNUNET_SYSERR, &my_identity, &incoming->key, peer, NULL); } #endif return GNUNET_YES; } if (get_max_send_delay ().rel_value > MAX_REQUEST_TIME.rel_value) { GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sending of previous replies took too long, backing off!\n"); increment_stats ("# route requests dropped due to high load"); decrease_max_send_delay (get_max_send_delay ()); #if DEBUG_DHT_ROUTING if ((debug_routes_extended) && (dhtlog_handle != NULL)) { /** Log routes that die due to high load! */ dhtlog_handle->insert_route (NULL, GNUNET_ntohll (incoming->unique_id), DHTLOG_ROUTE, ntohl (incoming->hop_count), GNUNET_SYSERR, &my_identity, &incoming->key, peer, NULL); } #endif return GNUNET_YES; } msg_ctx = GNUNET_malloc (sizeof (struct DHT_MessageContext)); msg_ctx->bloom = GNUNET_CONTAINER_bloomfilter_init (incoming->bloomfilter, DHT_BLOOM_SIZE, DHT_BLOOM_K); GNUNET_assert (msg_ctx->bloom != NULL); msg_ctx->hop_count = ntohl (incoming->hop_count); memcpy (&msg_ctx->key, &incoming->key, sizeof (GNUNET_HashCode)); msg_ctx->replication = ntohl (incoming->desired_replication_level); msg_ctx->unique_id = GNUNET_ntohll (incoming->unique_id); msg_ctx->msg_options = ntohl (incoming->options); if (GNUNET_DHT_RO_RECORD_ROUTE == (msg_ctx->msg_options & GNUNET_DHT_RO_RECORD_ROUTE)) { path_size = ntohl(incoming->outgoing_path_length) * sizeof(struct GNUNET_PeerIdentity); GNUNET_assert(ntohs(message->size) == (sizeof(struct GNUNET_DHT_P2PRouteMessage) + ntohs(enc_msg->size) + path_size)); route_path = (char *)&incoming[1]; route_path = route_path + ntohs(enc_msg->size); msg_ctx->path_history = GNUNET_malloc(sizeof(struct GNUNET_PeerIdentity) + path_size); memcpy(msg_ctx->path_history, route_path, path_size); memcpy(&msg_ctx->path_history[path_size], &my_identity, sizeof(struct GNUNET_PeerIdentity)); msg_ctx->path_history_len = ntohl(incoming->outgoing_path_length) + 1; } msg_ctx->network_size = ntohl (incoming->network_size); msg_ctx->peer = peer; msg_ctx->importance = DHT_DEFAULT_P2P_IMPORTANCE; msg_ctx->timeout = DHT_DEFAULT_P2P_TIMEOUT; demultiplex_message (enc_msg, msg_ctx); if (msg_ctx->bloom != NULL) { GNUNET_CONTAINER_bloomfilter_free (msg_ctx->bloom); msg_ctx->bloom = NULL; } GNUNET_free (msg_ctx); return GNUNET_YES; } /** * Core handler for p2p route results. * * @param cls closure * @param message message * @param peer peer identity this notification is about * @param atsi performance data * */ static int handle_dht_p2p_route_result (void *cls, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_MessageHeader *message, const struct GNUNET_TRANSPORT_ATS_Information *atsi) { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "`%s:%s': Received request from peer %s\n", my_short_id, "DHT", GNUNET_i2s (peer)); #endif struct GNUNET_DHT_P2PRouteResultMessage *incoming = (struct GNUNET_DHT_P2PRouteResultMessage *) message; struct GNUNET_MessageHeader *enc_msg = (struct GNUNET_MessageHeader *) &incoming[1]; struct DHT_MessageContext msg_ctx; #if DEBUG_PATH char *path_offset; unsigned int i; #endif if (ntohs (enc_msg->size) >= GNUNET_SERVER_MAX_MESSAGE_SIZE - 1) { GNUNET_break_op (0); return GNUNET_YES; } if (malicious_dropper == GNUNET_YES) { #if DEBUG_DHT_ROUTING if ((debug_routes_extended) && (dhtlog_handle != NULL)) { /** Log routes that die due to high load! */ dhtlog_handle->insert_route (NULL, GNUNET_ntohll (incoming->unique_id), DHTLOG_ROUTE, ntohl (incoming->hop_count), GNUNET_SYSERR, &my_identity, &incoming->key, peer, NULL); } #endif return GNUNET_YES; } memset (&msg_ctx, 0, sizeof (struct DHT_MessageContext)); // FIXME: call GNUNET_BLOCK_evaluate (...) -- instead of doing your own bloomfilter! msg_ctx.bloom = GNUNET_CONTAINER_bloomfilter_init (incoming->bloomfilter, DHT_BLOOM_SIZE, DHT_BLOOM_K); GNUNET_assert (msg_ctx.bloom != NULL); memcpy (&msg_ctx.key, &incoming->key, sizeof (GNUNET_HashCode)); msg_ctx.unique_id = GNUNET_ntohll (incoming->unique_id); msg_ctx.msg_options = ntohl (incoming->options); msg_ctx.hop_count = ntohl (incoming->hop_count); msg_ctx.peer = peer; msg_ctx.importance = DHT_DEFAULT_P2P_IMPORTANCE + 2; /* Make result routing a higher priority */ msg_ctx.timeout = DHT_DEFAULT_P2P_TIMEOUT; if ((GNUNET_DHT_RO_RECORD_ROUTE == (msg_ctx.msg_options & GNUNET_DHT_RO_RECORD_ROUTE)) && (ntohl (incoming->outgoing_path_length) > 0)) { if (ntohs(message->size) - sizeof(struct GNUNET_DHT_P2PRouteResultMessage) - ntohs(enc_msg->size) != ntohl (incoming->outgoing_path_length) * sizeof(struct GNUNET_PeerIdentity)) { GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Return message indicated a path was included, but sizes are wrong!\nTotal message size %d, enc_msg size %d, left over %d, expected %d\n", ntohs(message->size), ntohs(enc_msg->size), ntohs(message->size) - sizeof(struct GNUNET_DHT_P2PRouteResultMessage) - ntohs(enc_msg->size), ntohl(incoming->outgoing_path_length) * sizeof(struct GNUNET_PeerIdentity)); return GNUNET_NO; } msg_ctx.path_history = (char *)&incoming[1]; msg_ctx.path_history += ntohs(enc_msg->size); msg_ctx.path_history_len = ntohl (incoming->outgoing_path_length); #if DEBUG_PATH for (i = 0; i < msg_ctx.path_history_len; i++) { path_offset = &msg_ctx.path_history[i * sizeof(struct GNUNET_PeerIdentity)]; GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "(handle_p2p_route_result) Key %s Found peer %d:%s\n", GNUNET_h2s(&msg_ctx.key), i, GNUNET_i2s((struct GNUNET_PeerIdentity *)path_offset)); } #endif } route_result_message (enc_msg, &msg_ctx); return GNUNET_YES; } /** * Receive the HELLO from transport service, * free current and replace if necessary. * * @param cls NULL * @param message HELLO message of peer */ static void process_hello (void *cls, const struct GNUNET_MessageHeader *message) { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received our `%s' from transport service\n", "HELLO"); #endif GNUNET_assert (message != NULL); GNUNET_free_non_null (my_hello); my_hello = GNUNET_malloc (ntohs (message->size)); memcpy (my_hello, message, ntohs (message->size)); } /** * Task run during shutdown. * * @param cls unused * @param tc unused */ static void shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { int bucket_count; struct PeerInfo *pos; if (transport_handle != NULL) { GNUNET_free_non_null (my_hello); GNUNET_TRANSPORT_get_hello_cancel (transport_handle, &process_hello, NULL); GNUNET_TRANSPORT_disconnect (transport_handle); } for (bucket_count = lowest_bucket; bucket_count < MAX_BUCKETS; bucket_count++) { while (k_buckets[bucket_count].head != NULL) { pos = k_buckets[bucket_count].head; #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Removing peer %s from bucket %d!\n", my_short_id, "DHT", GNUNET_i2s (&pos->id), bucket_count); #endif delete_peer (pos, bucket_count); } } if (coreAPI != NULL) { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Disconnecting core!\n", my_short_id, "DHT"); #endif GNUNET_CORE_disconnect (coreAPI); coreAPI = NULL; } if (datacache != NULL) { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Destroying datacache!\n", my_short_id, "DHT"); #endif GNUNET_DATACACHE_destroy (datacache); datacache = NULL; } if (stats != NULL) { GNUNET_STATISTICS_destroy (stats, GNUNET_YES); stats = NULL; } if (dhtlog_handle != NULL) { GNUNET_DHTLOG_disconnect (dhtlog_handle); dhtlog_handle = NULL; } if (block_context != NULL) { GNUNET_BLOCK_context_destroy (block_context); block_context = NULL; } GNUNET_free_non_null (my_short_id); my_short_id = NULL; } /** * To be called on core init/fail. * * @param cls service closure * @param server handle to the server for this service * @param identity the public identity of this peer * @param publicKey the public key of this peer */ void core_init (void *cls, struct GNUNET_CORE_Handle *server, const struct GNUNET_PeerIdentity *identity, const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *publicKey) { if (server == NULL) { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s: Connection to core FAILED!\n", "dht", GNUNET_i2s (identity)); #endif GNUNET_SCHEDULER_cancel (cleanup_task); GNUNET_SCHEDULER_add_now (&shutdown_task, NULL); return; } #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s: Core connection initialized, I am peer: %s\n", "dht", GNUNET_i2s (identity)); #endif /* Copy our identity so we can use it */ memcpy (&my_identity, identity, sizeof (struct GNUNET_PeerIdentity)); if (my_short_id != NULL) GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "%s Receive CORE INIT message but have already been initialized! Did CORE fail?\n", "DHT SERVICE"); my_short_id = GNUNET_strdup (GNUNET_i2s (&my_identity)); /* Set the server to local variable */ coreAPI = server; if (dhtlog_handle != NULL) dhtlog_handle->insert_node (NULL, &my_identity); } static struct GNUNET_SERVER_MessageHandler plugin_handlers[] = { {&handle_dht_local_route_request, NULL, GNUNET_MESSAGE_TYPE_DHT_LOCAL_ROUTE, 0}, {&handle_dht_local_route_stop, NULL, GNUNET_MESSAGE_TYPE_DHT_LOCAL_ROUTE_STOP, 0}, {&handle_dht_control_message, NULL, GNUNET_MESSAGE_TYPE_DHT_CONTROL, 0}, {NULL, NULL, 0, 0} }; static struct GNUNET_CORE_MessageHandler core_handlers[] = { {&handle_dht_p2p_route_request, GNUNET_MESSAGE_TYPE_DHT_P2P_ROUTE, 0}, {&handle_dht_p2p_route_result, GNUNET_MESSAGE_TYPE_DHT_P2P_ROUTE_RESULT, 0}, {NULL, 0, 0} }; /** * Method called whenever a peer connects. * * @param cls closure * @param peer peer identity this notification is about * @param atsi performance data */ static void handle_core_connect (void *cls, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_TRANSPORT_ATS_Information *atsi) { struct PeerInfo *ret; struct DHTPutEntry *put_entry; /* Check for connect to self message */ if (0 == memcmp(&my_identity, peer, sizeof(struct GNUNET_PeerIdentity))) return; #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Receives core connect message for peer %s distance %d!\n", my_short_id, "dht", GNUNET_i2s (peer), distance); #endif if (GNUNET_YES == GNUNET_CONTAINER_multihashmap_contains (all_known_peers, &peer->hashPubKey)) { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Received %s message for peer %s, but already have peer in RT!", my_short_id, "DHT", "CORE CONNECT", GNUNET_i2s (peer)); #endif return; } if ((datacache != NULL) && (GNUNET_YES == put_peer_identities)) { put_entry = GNUNET_malloc(sizeof(struct DHTPutEntry) + sizeof (struct GNUNET_PeerIdentity)); put_entry->path_length = 0; put_entry->data_size = sizeof (struct GNUNET_PeerIdentity); memcpy(&put_entry[1], peer, sizeof (struct GNUNET_PeerIdentity)); GNUNET_DATACACHE_put (datacache, &peer->hashPubKey, sizeof(struct DHTPutEntry) + sizeof (struct GNUNET_PeerIdentity), (char *)put_entry, GNUNET_BLOCK_TYPE_DHT_HELLO, GNUNET_TIME_absolute_get_forever ()); GNUNET_free (put_entry); } else if (datacache == NULL) GNUNET_log(GNUNET_ERROR_TYPE_WARNING, "DHT has no connection to datacache!\n"); ret = try_add_peer (peer, find_current_bucket (&peer->hashPubKey), atsi); if (ret != NULL) { newly_found_peers++; GNUNET_CONTAINER_multihashmap_put (all_known_peers, &peer->hashPubKey, ret, GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY); } #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s Adding peer to routing list: %s\n", my_short_id, "DHT", ret == NULL ? "NOT ADDED" : "PEER ADDED"); #endif } /** * Method called whenever a peer disconnects. * * @param cls closure * @param peer peer identity this notification is about */ static void handle_core_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer) { struct PeerInfo *to_remove; int current_bucket; /* Check for disconnect from self message */ if (0 == memcmp(&my_identity, peer, sizeof(struct GNUNET_PeerIdentity))) return; #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s: Received peer disconnect message for peer `%s' from %s\n", my_short_id, "DHT", GNUNET_i2s (peer), "CORE"); #endif if (GNUNET_YES != GNUNET_CONTAINER_multihashmap_contains (all_known_peers, &peer->hashPubKey)) { #if DEBUG_DHT GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "%s:%s: do not have peer `%s' in RT, can't disconnect!\n", my_short_id, "DHT", GNUNET_i2s (peer)); #endif return; } increment_stats (STAT_DISCONNECTS); GNUNET_assert (GNUNET_CONTAINER_multihashmap_contains (all_known_peers, &peer->hashPubKey)); to_remove = GNUNET_CONTAINER_multihashmap_get (all_known_peers, &peer->hashPubKey); GNUNET_assert (to_remove != NULL); GNUNET_assert (0 == memcmp (peer, &to_remove->id, sizeof (struct GNUNET_PeerIdentity))); current_bucket = find_current_bucket (&to_remove->id.hashPubKey); delete_peer (to_remove, current_bucket); } /** * Process dht requests. * * @param cls closure * @param server the initialized server * @param c configuration to use */ static void run (void *cls, struct GNUNET_SERVER_Handle *server, const struct GNUNET_CONFIGURATION_Handle *c) { struct GNUNET_TIME_Relative next_send_time; unsigned long long temp_config_num; char *converge_modifier_buf; cfg = c; datacache = GNUNET_DATACACHE_create (cfg, "dhtcache"); GNUNET_SERVER_add_handlers (server, plugin_handlers); GNUNET_SERVER_disconnect_notify (server, &handle_client_disconnect, NULL); coreAPI = GNUNET_CORE_connect (cfg, /* Main configuration */ DEFAULT_CORE_QUEUE_SIZE, /* queue size */ NULL, /* Closure passed to DHT functions */ &core_init, /* Call core_init once connected */ &handle_core_connect, /* Handle connects */ &handle_core_disconnect, /* remove peers on disconnects */ NULL, /* Do we care about "status" updates? */ NULL, /* Don't want notified about all incoming messages */ GNUNET_NO, /* For header only inbound notification */ NULL, /* Don't want notified about all outbound messages */ GNUNET_NO, /* For header only outbound notification */ core_handlers); /* Register these handlers */ if (coreAPI == NULL) return; transport_handle = GNUNET_TRANSPORT_connect (cfg, NULL, NULL, NULL, NULL, NULL); if (transport_handle != NULL) GNUNET_TRANSPORT_get_hello (transport_handle, &process_hello, NULL); else GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Failed to connect to transport service!\n"); block_context = GNUNET_BLOCK_context_create (cfg); lowest_bucket = MAX_BUCKETS - 1; forward_list.hashmap = GNUNET_CONTAINER_multihashmap_create (MAX_OUTSTANDING_FORWARDS / 10); forward_list.minHeap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN); all_known_peers = GNUNET_CONTAINER_multihashmap_create (MAX_BUCKETS / 8); recent_find_peer_requests = GNUNET_CONTAINER_multihashmap_create (MAX_BUCKETS / 8); GNUNET_assert (all_known_peers != NULL); if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht_testing", "mysql_logging")) { debug_routes = GNUNET_YES; } if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "strict_kademlia")) { strict_kademlia = GNUNET_YES; } if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "stop_on_closest")) { stop_on_closest = GNUNET_YES; } if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "stop_found")) { stop_on_found = GNUNET_YES; } if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "malicious_getter")) { malicious_getter = GNUNET_YES; if (GNUNET_NO == GNUNET_CONFIGURATION_get_value_number (cfg, "DHT", "MALICIOUS_GET_FREQUENCY", &malicious_get_frequency)) malicious_get_frequency = DEFAULT_MALICIOUS_GET_FREQUENCY; } if (GNUNET_YES != GNUNET_CONFIGURATION_get_value_number (cfg, "DHT", "MAX_HOPS", &max_hops)) { max_hops = DEFAULT_MAX_HOPS; } if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "DHT", "USE_MAX_HOPS")) { use_max_hops = GNUNET_YES; } if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "malicious_putter")) { malicious_putter = GNUNET_YES; if (GNUNET_NO == GNUNET_CONFIGURATION_get_value_number (cfg, "DHT", "MALICIOUS_PUT_FREQUENCY", &malicious_put_frequency)) malicious_put_frequency = DEFAULT_MALICIOUS_PUT_FREQUENCY; } dht_republish_frequency = GNUNET_DHT_DEFAULT_REPUBLISH_FREQUENCY; if (GNUNET_OK == GNUNET_CONFIGURATION_get_value_number (cfg, "DHT", "REPLICATION_FREQUENCY", &temp_config_num)) { dht_republish_frequency = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, temp_config_num); } if (GNUNET_OK == GNUNET_CONFIGURATION_get_value_number (cfg, "DHT", "bucket_size", &temp_config_num)) { bucket_size = (unsigned int) temp_config_num; } if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_number (cfg, "DHT", "kad_alpha", &kademlia_replication)) { kademlia_replication = DEFAULT_KADEMLIA_REPLICATION; } if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "malicious_dropper")) { malicious_dropper = GNUNET_YES; } if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "republish")) do_republish = GNUNET_NO; if (GNUNET_NO == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "do_find_peer")) { do_find_peer = GNUNET_NO; } else do_find_peer = GNUNET_YES; if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "use_real_distance")) use_real_distance = GNUNET_YES; if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht_testing", "mysql_logging_extended")) { debug_routes = GNUNET_YES; debug_routes_extended = GNUNET_YES; } #if DEBUG_DHT_ROUTING if (GNUNET_YES == debug_routes) { dhtlog_handle = GNUNET_DHTLOG_connect (cfg); if (dhtlog_handle == NULL) { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Could not connect to mysql logging server, logging will not happen!"); } } #endif converge_option = DHT_CONVERGE_BINARY; if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "converge_linear")) { converge_option = DHT_CONVERGE_LINEAR; } else if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "converge_exponential")) { converge_option = DHT_CONVERGE_EXPONENTIAL; } else if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "converge_random")) { converge_option = DHT_CONVERGE_RANDOM; } else if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "converge_binary")) { converge_option = DHT_CONVERGE_BINARY; } converge_modifier = 4.0; if (GNUNET_OK == GNUNET_CONFIGURATION_get_value_string (cfg, "dht", "converge_modifier", &converge_modifier_buf)) { if (1 != sscanf (converge_modifier_buf, "%f", &converge_modifier)) { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Failed to read decimal value for %s from `%s'\n", "CONVERGE_MODIFIER", converge_modifier_buf); converge_modifier = 0.0; } GNUNET_free (converge_modifier_buf); } if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "paper_forwarding")) paper_forwarding = GNUNET_YES; if (GNUNET_YES == GNUNET_CONFIGURATION_get_value_yesno (cfg, "dht", "put_peer_identities")) put_peer_identities = GNUNET_YES; stats = GNUNET_STATISTICS_create ("dht", cfg); if (stats != NULL) { GNUNET_STATISTICS_set (stats, STAT_ROUTES, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_ROUTE_FORWARDS, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_ROUTE_FORWARDS_CLOSEST, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_RESULTS, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_RESULTS_TO_CLIENT, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_RESULT_FORWARDS, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_GETS, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_PUTS, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_PUTS_INSERTED, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_FIND_PEER, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_FIND_PEER_START, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_GET_START, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_PUT_START, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_FIND_PEER_REPLY, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_FIND_PEER_ANSWER, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_BLOOM_FIND_PEER, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_GET_REPLY, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_GET_RESPONSE_START, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_HELLOS_PROVIDED, 0, GNUNET_NO); GNUNET_STATISTICS_set (stats, STAT_DISCONNECTS, 0, GNUNET_NO); } /* FIXME: if there are no recent requests then these never get freed, but alternative is _annoying_! */ recent.hashmap = GNUNET_CONTAINER_multihashmap_create (DHT_MAX_RECENT / 2); recent.minHeap = GNUNET_CONTAINER_heap_create (GNUNET_CONTAINER_HEAP_ORDER_MIN); if (GNUNET_YES == do_find_peer) { next_send_time.rel_value = DHT_MINIMUM_FIND_PEER_INTERVAL.rel_value + GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_STRONG, (DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value / 2) - DHT_MINIMUM_FIND_PEER_INTERVAL.rel_value); find_peer_context.start = GNUNET_TIME_absolute_get (); GNUNET_SCHEDULER_add_delayed (next_send_time, &send_find_peer_message, &find_peer_context); } /* Scheduled the task to clean up when shutdown is called */ cleanup_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &shutdown_task, NULL); } /** * The main function for the dht service. * * @param argc number of arguments from the command line * @param argv command line arguments * @return 0 ok, 1 on error */ int main (int argc, char *const *argv) { int ret; ret = (GNUNET_OK == GNUNET_SERVICE_run (argc, argv, "dht", GNUNET_SERVICE_OPTION_NONE, &run, NULL)) ? 0 : 1; GNUNET_assert (0 == GNUNET_CONTAINER_multihashmap_size (recent.hashmap)); GNUNET_assert (0 == GNUNET_CONTAINER_heap_get_size (recent.minHeap)); GNUNET_CONTAINER_multihashmap_destroy (recent_find_peer_requests); GNUNET_CONTAINER_multihashmap_destroy (recent.hashmap); GNUNET_CONTAINER_heap_destroy (recent.minHeap); return ret; }