-template for supriti/xvine

1 files changed, 2227 insertions, 0 deletions

diff --git a/src/dht/gnunet-service-xdht_neighbours.c b/src/dht/gnunet-service-xdht_neighbours.c
new file mode 100644
index 000000000..f15a33c79
--- /dev/null
+++ b/src/dht/gnunet-service-xdht_neighbours.c
@@ -0,0 +1,2227 @@
+/*
+     This file is part of GNUnet.
+     (C) 2009-2013 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-xdht_neighbours.c
+ * @brief GNUnet DHT service's bucket and neighbour management code
+ * @author Christian Grothoff
+ * @author Nathan Evans
+ */
+
+#include "platform.h"
+#include "gnunet_util_lib.h"
+#include "gnunet_block_lib.h"
+#include "gnunet_hello_lib.h"
+#include "gnunet_constants.h"
+#include "gnunet_protocols.h"
+#include "gnunet_nse_service.h"
+#include "gnunet_ats_service.h"
+#include "gnunet_core_service.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 "gnunet-service-dht.h"
+#include "gnunet-service-dht_clients.h"
+#include "gnunet-service-dht_datacache.h"
+#include "gnunet-service-dht_hello.h"
+#include "gnunet-service-dht_neighbours.h"
+#include "gnunet-service-dht_nse.h"
+#include "gnunet-service-dht_routing.h"
+#include <fenv.h>
+#include "dht.h"
+
+#define LOG_TRAFFIC(kind,...) GNUNET_log_from (kind, "dht-traffic",__VA_ARGS__)
+
+/**
+ * How many buckets will we allow total.
+ */
+#define MAX_BUCKETS sizeof (struct GNUNET_HashCode) * 8
+
+/**
+ * What is the maximum number of peers in a given bucket.
+ */
+#define DEFAULT_BUCKET_SIZE 8
+
+/**
+ * Desired replication level for FIND PEER requests
+ */
+#define FIND_PEER_REPLICATION_LEVEL 4
+
+/**
+ * Maximum allowed replication level for all requests.
+ */
+#define MAXIMUM_REPLICATION_LEVEL 16
+
+/**
+ * Maximum allowed number of pending messages per peer.
+ */
+#define MAXIMUM_PENDING_PER_PEER 64
+
+/**
+ * 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 least to wait before sending another find peer request.
+ */
+#define DHT_MINIMUM_FIND_PEER_INTERVAL GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 30)
+
+/**
+ * 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, 10)
+
+/**
+ * How long at most to wait for transmission of a GET request to another peer?
+ */
+#define GET_TIMEOUT GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES, 2)
+
+/**
+ * Hello address expiration
+ */
+extern struct GNUNET_TIME_Relative hello_expiration;
+
+
+GNUNET_NETWORK_STRUCT_BEGIN
+
+/**
+ * P2P PUT message
+ */
+struct PeerPutMessage
+{
+  /**
+   * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_PUT
+   */
+  struct GNUNET_MessageHeader header;
+
+  /**
+   * Processing options
+   */
+  uint32_t options GNUNET_PACKED;
+
+  /**
+   * Content type.
+   */
+  uint32_t type GNUNET_PACKED;
+
+  /**
+   * Hop count
+   */
+  uint32_t hop_count GNUNET_PACKED;
+
+  /**
+   * Replication level for this message
+   */
+  uint32_t desired_replication_level GNUNET_PACKED;
+
+  /**
+   * Length of the PUT path that follows (if tracked).
+   */
+  uint32_t put_path_length GNUNET_PACKED;
+
+  /**
+   * When does the content expire?
+   */
+  struct GNUNET_TIME_AbsoluteNBO expiration_time;
+
+  /**
+   * Bloomfilter (for peer identities) to stop circular routes
+   */
+  char bloomfilter[DHT_BLOOM_SIZE];
+
+  /**
+   * The key we are storing under.
+   */
+  struct GNUNET_HashCode key;
+
+  /* put path (if tracked) */
+
+  /* Payload */
+
+};
+
+
+/**
+ * P2P Result message
+ */
+struct PeerResultMessage
+{
+  /**
+   * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT
+   */
+  struct GNUNET_MessageHeader header;
+
+  /**
+   * Content type.
+   */
+  uint32_t type GNUNET_PACKED;
+
+  /**
+   * Length of the PUT path that follows (if tracked).
+   */
+  uint32_t put_path_length GNUNET_PACKED;
+
+  /**
+   * Length of the GET path that follows (if tracked).
+   */
+  uint32_t get_path_length GNUNET_PACKED;
+
+  /**
+   * When does the content expire?
+   */
+  struct GNUNET_TIME_AbsoluteNBO expiration_time;
+
+  /**
+   * The key of the corresponding GET request.
+   */
+  struct GNUNET_HashCode key;
+
+  /* put path (if tracked) */
+
+  /* get path (if tracked) */
+
+  /* Payload */
+
+};
+
+
+/**
+ * P2P GET message
+ */
+struct PeerGetMessage
+{
+  /**
+   * Type: #GNUNET_MESSAGE_TYPE_DHT_P2P_GET
+   */
+  struct GNUNET_MessageHeader header;
+
+  /**
+   * Processing options
+   */
+  uint32_t options GNUNET_PACKED;
+
+  /**
+   * Desired content type.
+   */
+  uint32_t type GNUNET_PACKED;
+
+  /**
+   * Hop count
+   */
+  uint32_t hop_count GNUNET_PACKED;
+
+  /**
+   * Desired replication level for this request.
+   */
+  uint32_t desired_replication_level GNUNET_PACKED;
+
+  /**
+   * Size of the extended query.
+   */
+  uint32_t xquery_size;
+
+  /**
+   * Bloomfilter mutator.
+   */
+  uint32_t bf_mutator;
+
+  /**
+   * Bloomfilter (for peer identities) to stop circular routes
+   */
+  char bloomfilter[DHT_BLOOM_SIZE];
+
+  /**
+   * The key we are looking for.
+   */
+  struct GNUNET_HashCode key;
+
+  /* xquery */
+
+  /* result bloomfilter */
+
+};
+GNUNET_NETWORK_STRUCT_END
+
+/**
+ * Linked list of messages to send to a particular other peer.
+ */
+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.  FIXME: used? useful?
+   */
+  unsigned int importance;
+
+  /**
+   * When does this message time out?
+   */
+  struct GNUNET_TIME_Absolute timeout;
+
+  /**
+   * Actual message to be sent, allocated at the end of the struct:
+   * // msg = (cast) &pm[1];
+   * // memcpy (&pm[1], data, len);
+   */
+  const struct GNUNET_MessageHeader *msg;
+
+};
+
+
+/**
+ * Entry for a peer in a bucket.
+ */
+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 preference updates
+   */
+  GNUNET_SCHEDULER_TaskIdentifier preference_task;
+
+  /**
+   * 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
+
+};
+
+
+/**
+ * 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;
+};
+
+
+/**
+ * Do we cache all results that we are routing in the local datacache?
+ */
+static int cache_results;
+
+/**
+ * Should routing details be logged to stderr (for debugging)?
+ */
+static int log_route_details_stderr;
+
+/**
+ * The lowest currently used bucket, initially 0 (for 0-bits matching bucket).
+ */
+static unsigned int closest_bucket;
+
+/**
+ * How many peers have we added since we sent out our last
+ * find peer request?
+ */
+static unsigned int newly_found_peers;
+
+/**
+ * Option for testing that disables the 'connect' function of the DHT.
+ */
+static int disable_try_connect;
+
+/**
+ * The buckets.  Array of size MAX_BUCKET_SIZE.  Offset 0 means 0 bits matching.
+ */
+static struct PeerBucket k_buckets[MAX_BUCKETS];
+
+/**
+ * Hash map of all known peers, for easy removal from k_buckets on disconnect.
+ */
+static struct GNUNET_CONTAINER_MultiPeerMap *all_known_peers;
+
+/**
+ * Maximum size for each bucket.
+ */
+static unsigned int bucket_size = DEFAULT_BUCKET_SIZE;
+
+/**
+ * Task that sends FIND PEER requests.
+ */
+static GNUNET_SCHEDULER_TaskIdentifier find_peer_task;
+
+/**
+ * Identity of this peer.
+ */
+static struct GNUNET_PeerIdentity my_identity;
+
+/**
+ * Hash of the identity of this peer.
+ */
+static struct GNUNET_HashCode my_identity_hash;
+
+/**
+ * Handle to CORE.
+ */
+static struct GNUNET_CORE_Handle *core_api;
+
+/**
+ * Handle to ATS.
+ */
+static struct GNUNET_ATS_PerformanceHandle *atsAPI;
+
+
+
+/**
+ * Find the optimal bucket for this key.
+ *
+ * @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 struct GNUNET_HashCode *hc)
+{
+  unsigned int bits;
+
+  bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity_hash, hc);
+  if (bits == MAX_BUCKETS)
+  {
+    /* How can all bits match? Got my own ID? */
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  return MAX_BUCKETS - bits - 1;
+}
+
+
+/**
+ * Let GNUnet core know that we like the given peer.
+ *
+ * @param cls the `struct PeerInfo` of the peer
+ * @param tc scheduler context.
+ */
+static void
+update_core_preference (void *cls,
+                        const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct PeerInfo *peer = cls;
+  uint64_t preference;
+  unsigned int matching;
+  int bucket;
+  struct GNUNET_HashCode phash;
+
+  peer->preference_task = GNUNET_SCHEDULER_NO_TASK;
+  if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
+    return;
+  GNUNET_CRYPTO_hash (&peer->id,
+                      sizeof (struct GNUNET_PeerIdentity),
+                      &phash);
+  matching =
+      GNUNET_CRYPTO_hash_matching_bits (&my_identity_hash,
+                                        &phash);
+  if (matching >= 64)
+    matching = 63;
+  bucket = find_bucket (&phash);
+  if (bucket == GNUNET_SYSERR)
+    preference = 0;
+  else
+  {
+    GNUNET_assert (k_buckets[bucket].peers_size != 0);
+    preference = (1LL << matching) / k_buckets[bucket].peers_size;
+  }
+  if (preference == 0)
+  {
+    peer->preference_task =
+        GNUNET_SCHEDULER_add_delayed (DHT_DEFAULT_PREFERENCE_INTERVAL,
+                                      &update_core_preference, peer);
+    return;
+  }
+  GNUNET_STATISTICS_update (GDS_stats,
+                            gettext_noop ("# Preference updates given to core"),
+                            1, GNUNET_NO);
+  GNUNET_ATS_performance_change_preference (atsAPI, &peer->id,
+                                GNUNET_ATS_PREFERENCE_BANDWIDTH,
+                                (double) preference, GNUNET_ATS_PREFERENCE_END);
+  peer->preference_task =
+      GNUNET_SCHEDULER_add_delayed (DHT_DEFAULT_PREFERENCE_INTERVAL,
+                                    &update_core_preference, peer);
+
+
+}
+
+
+/**
+ * Closure for 'add_known_to_bloom'.
+ */
+struct BloomConstructorContext
+{
+  /**
+   * Bloom filter under construction.
+   */
+  struct GNUNET_CONTAINER_BloomFilter *bloom;
+
+  /**
+   * Mutator to use.
+   */
+  uint32_t bf_mutator;
+};
+
+
+/**
+ * Add each of the peers we already know to the bloom filter of
+ * the request so that we don't get duplicate HELLOs.
+ *
+ * @param cls the 'struct BloomConstructorContext'.
+ * @param key peer identity to add to the bloom filter
+ * @param value value the peer information (unused)
+ * @return #GNUNET_YES (we should continue to iterate)
+ */
+static int
+add_known_to_bloom (void *cls,
+                    const struct GNUNET_PeerIdentity *key,
+                    void *value)
+{
+  struct BloomConstructorContext *ctx = cls;
+  struct GNUNET_HashCode key_hash;
+  struct GNUNET_HashCode mh;
+
+  GNUNET_CRYPTO_hash (key, sizeof (struct GNUNET_PeerIdentity), &key_hash);
+  GNUNET_BLOCK_mingle_hash (&key_hash, ctx->bf_mutator, &mh);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Adding known peer (%s) to bloomfilter for FIND PEER with mutation %u\n",
+              GNUNET_i2s (key), ctx->bf_mutator);
+  GNUNET_CONTAINER_bloomfilter_add (ctx->bloom, &mh);
+  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_TIME_Relative next_send_time;
+  struct BloomConstructorContext bcc;
+  struct GNUNET_CONTAINER_BloomFilter *peer_bf;
+
+  find_peer_task = GNUNET_SCHEDULER_NO_TASK;
+  if ((tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN) != 0)
+    return;
+  if (newly_found_peers > bucket_size)
+  {
+    /* If we are finding many peers already, no need to send out our request right now! */
+    find_peer_task =
+        GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MINUTES,
+                                      &send_find_peer_message, NULL);
+    newly_found_peers = 0;
+    return;
+  }
+  bcc.bf_mutator =
+      GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, UINT32_MAX);
+  bcc.bloom =
+      GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
+                                         GNUNET_CONSTANTS_BLOOMFILTER_K);
+  GNUNET_CONTAINER_multipeermap_iterate (all_known_peers, &add_known_to_bloom,
+                                         &bcc);
+  GNUNET_STATISTICS_update (GDS_stats,
+                            gettext_noop ("# FIND PEER messages initiated"), 1,
+                            GNUNET_NO);
+  peer_bf =
+      GNUNET_CONTAINER_bloomfilter_init (NULL, DHT_BLOOM_SIZE,
+                                         GNUNET_CONSTANTS_BLOOMFILTER_K);
+  // FIXME: pass priority!?
+  GDS_NEIGHBOURS_handle_get (GNUNET_BLOCK_TYPE_DHT_HELLO,
+                             GNUNET_DHT_RO_FIND_PEER,
+                             FIND_PEER_REPLICATION_LEVEL, 0,
+                             &my_identity_hash, NULL, 0, bcc.bloom,
+                             bcc.bf_mutator, peer_bf);
+  GNUNET_CONTAINER_bloomfilter_free (peer_bf);
+  GNUNET_CONTAINER_bloomfilter_free (bcc.bloom);
+  /* schedule next round */
+  next_send_time.rel_value_us =
+      DHT_MINIMUM_FIND_PEER_INTERVAL.rel_value_us +
+      GNUNET_CRYPTO_random_u64 (GNUNET_CRYPTO_QUALITY_WEAK,
+                                DHT_MAXIMUM_FIND_PEER_INTERVAL.rel_value_us /
+                                (newly_found_peers + 1));
+  newly_found_peers = 0;
+  find_peer_task =
+      GNUNET_SCHEDULER_add_delayed (next_send_time, &send_find_peer_message,
+                                    NULL);
+}
+
+
+/**
+ * Method called whenever a peer connects.
+ *
+ * @param cls closure
+ * @param peer peer identity this notification is about
+ */
+static void
+handle_core_connect (void *cls, const struct GNUNET_PeerIdentity *peer)
+{
+  struct PeerInfo *ret;
+  struct GNUNET_HashCode phash;
+  int peer_bucket;
+
+  /* Check for connect to self message */
+  if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
+    return;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Connected to %s\n",
+              GNUNET_i2s (peer));
+  if (GNUNET_YES ==
+      GNUNET_CONTAINER_multipeermap_contains (all_known_peers,
+                                              peer))
+  {
+    GNUNET_break (0);
+    return;
+  }
+  GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# peers connected"), 1,
+                            GNUNET_NO);
+  GNUNET_CRYPTO_hash (peer,
+                      sizeof (struct GNUNET_PeerIdentity),
+                      &phash);
+  peer_bucket = find_bucket (&phash);
+  GNUNET_assert ((peer_bucket >= 0) && (peer_bucket < MAX_BUCKETS));
+  ret = GNUNET_malloc (sizeof (struct PeerInfo));
+#if 0
+  ret->latency = latency;
+  ret->distance = distance;
+#endif
+  ret->id = *peer;
+  GNUNET_CONTAINER_DLL_insert_tail (k_buckets[peer_bucket].head,
+                                    k_buckets[peer_bucket].tail, ret);
+  k_buckets[peer_bucket].peers_size++;
+  closest_bucket = GNUNET_MAX (closest_bucket, peer_bucket);
+  if ((peer_bucket > 0) && (k_buckets[peer_bucket].peers_size <= bucket_size))
+  {
+    ret->preference_task =
+        GNUNET_SCHEDULER_add_now (&update_core_preference, ret);
+    newly_found_peers++;
+  }
+  GNUNET_assert (GNUNET_OK ==
+                 GNUNET_CONTAINER_multipeermap_put (all_known_peers,
+                                                    peer, ret,
+                                                    GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
+  if (1 == GNUNET_CONTAINER_multipeermap_size (all_known_peers) &&
+      (GNUNET_YES != disable_try_connect))
+  {
+    /* got a first connection, good time to start with FIND PEER requests... */
+    find_peer_task = GNUNET_SCHEDULER_add_now (&send_find_peer_message, NULL);
+  }
+}
+
+
+/**
+ * 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;
+  struct P2PPendingMessage *pos;
+  unsigned int discarded;
+  struct GNUNET_HashCode phash;
+
+  /* Check for disconnect from self message */
+  if (0 == memcmp (&my_identity, peer, sizeof (struct GNUNET_PeerIdentity)))
+    return;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Disconnected %s\n",
+              GNUNET_i2s (peer));
+  to_remove =
+      GNUNET_CONTAINER_multipeermap_get (all_known_peers, peer);
+  if (NULL == to_remove)
+  {
+    GNUNET_break (0);
+    return;
+  }
+  GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# peers connected"), -1,
+                            GNUNET_NO);
+  GNUNET_assert (GNUNET_YES ==
+                 GNUNET_CONTAINER_multipeermap_remove (all_known_peers,
+                                                       peer,
+                                                       to_remove));
+  if (GNUNET_SCHEDULER_NO_TASK != to_remove->preference_task)
+  {
+    GNUNET_SCHEDULER_cancel (to_remove->preference_task);
+    to_remove->preference_task = GNUNET_SCHEDULER_NO_TASK;
+  }
+  GNUNET_CRYPTO_hash (peer,
+                      sizeof (struct GNUNET_PeerIdentity),
+                      &phash);
+  current_bucket = find_bucket (&phash);
+  GNUNET_assert (current_bucket >= 0);
+  GNUNET_CONTAINER_DLL_remove (k_buckets[current_bucket].head,
+                               k_buckets[current_bucket].tail, to_remove);
+  GNUNET_assert (k_buckets[current_bucket].peers_size > 0);
+  k_buckets[current_bucket].peers_size--;
+  while ((closest_bucket > 0) && (k_buckets[closest_bucket].peers_size == 0))
+    closest_bucket--;
+
+  if (to_remove->th != NULL)
+  {
+    GNUNET_CORE_notify_transmit_ready_cancel (to_remove->th);
+    to_remove->th = NULL;
+  }
+  discarded = 0;
+  while (NULL != (pos = to_remove->head))
+  {
+    GNUNET_CONTAINER_DLL_remove (to_remove->head, to_remove->tail, pos);
+    discarded++;
+    GNUNET_free (pos);
+  }
+  GNUNET_STATISTICS_update (GDS_stats,
+                            gettext_noop
+                            ("# Queued messages discarded (peer disconnected)"),
+                            discarded, GNUNET_NO);
+  GNUNET_free (to_remove);
+}
+
+
+/**
+ * Called when core is ready to send a message we asked for
+ * out to the destination.
+ *
+ * @param cls the 'struct PeerInfo' of the target peer
+ * @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;
+  while ((NULL != (pending = peer->head)) &&
+         (0 == GNUNET_TIME_absolute_get_remaining (pending->timeout).rel_value_us))
+  {
+    peer->pending_count--;
+    GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, pending);
+    GNUNET_free (pending);
+  }
+  if (pending == NULL)
+  {
+    /* no messages pending */
+    return 0;
+  }
+  if (buf == NULL)
+  {
+    peer->th =
+        GNUNET_CORE_notify_transmit_ready (core_api, GNUNET_NO,
+                                           pending->importance,
+                                           GNUNET_TIME_absolute_get_remaining
+                                           (pending->timeout), &peer->id,
+                                           ntohs (pending->msg->size),
+                                           &core_transmit_notify, peer);
+    GNUNET_break (NULL != peer->th);
+    return 0;
+  }
+  off = 0;
+  while ((NULL != (pending = peer->head)) &&
+         (size - off >= (msize = ntohs (pending->msg->size))))
+  {
+    GNUNET_STATISTICS_update (GDS_stats,
+                              gettext_noop
+                              ("# Bytes transmitted to other peers"), msize,
+                              GNUNET_NO);
+    memcpy (&cbuf[off], pending->msg, msize);
+    off += msize;
+    peer->pending_count--;
+    GNUNET_CONTAINER_DLL_remove (peer->head, peer->tail, pending);
+    GNUNET_free (pending);
+  }
+  if (peer->head != NULL)
+  {
+    peer->th =
+        GNUNET_CORE_notify_transmit_ready (core_api, GNUNET_NO,
+                                           pending->importance,
+                                           GNUNET_TIME_absolute_get_remaining
+                                           (pending->timeout), &peer->id, msize,
+                                           &core_transmit_notify, peer);
+    GNUNET_break (NULL != peer->th);
+  }
+  return off;
+}
+
+
+/**
+ * Transmit all messages in the peer's message queue.
+ *
+ * @param peer message queue to process
+ */
+static void
+process_peer_queue (struct PeerInfo *peer)
+{
+  struct P2PPendingMessage *pending;
+
+  if (NULL == (pending = peer->head))
+    return;
+  if (NULL != peer->th)
+    return;
+  GNUNET_STATISTICS_update (GDS_stats,
+                            gettext_noop
+                            ("# Bytes of bandwidth requested from core"),
+                            ntohs (pending->msg->size), GNUNET_NO);
+  peer->th =
+      GNUNET_CORE_notify_transmit_ready (core_api, GNUNET_NO,
+                                         pending->importance,
+                                         GNUNET_TIME_absolute_get_remaining
+                                         (pending->timeout), &peer->id,
+                                         ntohs (pending->msg->size),
+                                         &core_transmit_notify, peer);
+  GNUNET_break (NULL != peer->th);
+}
+
+
+/**
+ * To how many peers should we (on average) forward the request to
+ * obtain the desired target_replication count (on average).
+ *
+ * @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 (uint32_t hop_count, uint32_t target_replication)
+{
+  uint32_t random_value;
+  uint32_t forward_count;
+  float target_value;
+
+  if (hop_count > GDS_NSE_get () * 4.0)
+  {
+    /* forcefully terminate */
+    GNUNET_STATISTICS_update (GDS_stats,
+                              gettext_noop ("# requests TTL-dropped"),
+                              1, GNUNET_NO);
+    return 0;
+  }
+  if (hop_count > GDS_NSE_get () * 2.0)
+  {
+    /* Once we have reached our ideal number of hops, only forward to 1 peer */
+    return 1;
+  }
+  /* bound by system-wide maximum */
+  target_replication =
+      GNUNET_MIN (MAXIMUM_REPLICATION_LEVEL, target_replication);
+  target_value =
+      1 + (target_replication - 1.0) / (GDS_NSE_get () +
+                                        ((float) (target_replication - 1.0) *
+                                         hop_count));
+  /* Set forward count to floor of target_value */
+  forward_count = (uint32_t) 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_WEAK, UINT32_MAX);
+  if (random_value < (target_value * UINT32_MAX))
+    forward_count++;
+  return forward_count;
+}
+
+
+/**
+ * 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.
+ *
+ * @param target
+ * @param have
+ * @return 0 if have==target, otherwise a number
+ *           that is larger as the distance between
+ *           the two hash codes increases
+ */
+static unsigned int
+get_distance (const struct GNUNET_HashCode *target,
+              const struct 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 (struct 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;
+}
+
+
+/**
+ * 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 key 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.
+ */
+static int
+am_closest_peer (const struct GNUNET_HashCode *key,
+                 const struct GNUNET_CONTAINER_BloomFilter *bloom)
+{
+  int bits;
+  int other_bits;
+  int bucket_num;
+  int count;
+  struct PeerInfo *pos;
+  struct GNUNET_HashCode phash;
+
+  if (0 == memcmp (&my_identity_hash, key, sizeof (struct GNUNET_HashCode)))
+    return GNUNET_YES;
+  bucket_num = find_bucket (key);
+  GNUNET_assert (bucket_num >= 0);
+  bits = GNUNET_CRYPTO_hash_matching_bits (&my_identity_hash, key);
+  pos = k_buckets[bucket_num].head;
+  count = 0;
+  while ((pos != NULL) && (count < bucket_size))
+  {
+    GNUNET_CRYPTO_hash (&pos->id,
+                        sizeof (struct GNUNET_PeerIdentity),
+                        &phash);
+    if ((bloom != NULL) &&
+        (GNUNET_YES ==
+         GNUNET_CONTAINER_bloomfilter_test (bloom, &phash)))
+    {
+      pos = pos->next;
+      continue;                 /* Skip already checked entries */
+    }
+    other_bits = GNUNET_CRYPTO_hash_matching_bits (&phash, key);
+    if (other_bits > bits)
+      return GNUNET_NO;
+    if (other_bits == bits)     /* We match the same number of bits */
+      return GNUNET_YES;
+    pos = pos->next;
+  }
+  /* No peers closer, we are the closest! */
+  return GNUNET_YES;
+}
+
+
+/**
+ * Select a peer from the routing table that would be a good routing
+ * destination for sending a message for "key".  The resulting peer
+ * must not be in the set of blocked peers.<p>
+ *
+ * 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.
+ *
+ * FIXME: double-check that this is fine
+ *
+ *
+ * @param key 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 struct GNUNET_HashCode * key,
+             const struct GNUNET_CONTAINER_BloomFilter *bloom, uint32_t hops)
+{
+  unsigned int bc;
+  unsigned int count;
+  unsigned int selected;
+  struct PeerInfo *pos;
+  unsigned int dist;
+  unsigned int smallest_distance;
+  struct PeerInfo *chosen;
+  struct GNUNET_HashCode phash;
+
+  if (hops >= GDS_NSE_get ())
+  {
+    /* greedy selection (closest peer that is not in bloomfilter) */
+    smallest_distance = UINT_MAX;
+    chosen = NULL;
+    for (bc = 0; bc <= closest_bucket; bc++)
+    {
+      pos = k_buckets[bc].head;
+      count = 0;
+      while ((pos != NULL) && (count < bucket_size))
+      {
+        GNUNET_CRYPTO_hash (&pos->id,
+                            sizeof (struct GNUNET_PeerIdentity),
+                            &phash);
+        if ((bloom == NULL) ||
+            (GNUNET_NO ==
+             GNUNET_CONTAINER_bloomfilter_test (bloom, &phash)))
+        {
+          dist = get_distance (key, &phash);
+          if (dist < smallest_distance)
+          {
+            chosen = pos;
+            smallest_distance = dist;
+          }
+        }
+        else
+        {
+          GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                      "Excluded peer `%s' due to BF match in greedy routing for %s\n",
+                      GNUNET_i2s (&pos->id), GNUNET_h2s (key));
+          GNUNET_STATISTICS_update (GDS_stats,
+                                    gettext_noop
+                                    ("# Peers excluded from routing due to Bloomfilter"),
+                                    1, GNUNET_NO);
+          dist = get_distance (key, &phash);
+          if (dist < smallest_distance)
+          {
+            chosen = NULL;
+            smallest_distance = dist;
+          }
+        }
+        count++;
+        pos = pos->next;
+      }
+    }
+    if (NULL == chosen)
+      GNUNET_STATISTICS_update (GDS_stats,
+                                gettext_noop ("# Peer selection failed"), 1,
+                                GNUNET_NO);
+    return chosen;
+  }
+
+  /* select "random" peer */
+  /* count number of peers that are available and not filtered */
+  count = 0;
+  for (bc = 0; bc <= closest_bucket; bc++)
+  {
+    pos = k_buckets[bc].head;
+    while ((pos != NULL) && (count < bucket_size))
+    {
+      GNUNET_CRYPTO_hash (&pos->id,
+                          sizeof (struct GNUNET_PeerIdentity),
+                          &phash);
+      if ((bloom != NULL) &&
+          (GNUNET_YES ==
+           GNUNET_CONTAINER_bloomfilter_test (bloom, &phash)))
+      {
+        GNUNET_STATISTICS_update (GDS_stats,
+                                  gettext_noop
+                                  ("# Peers excluded from routing due to Bloomfilter"),
+                                  1, GNUNET_NO);
+        GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                    "Excluded peer `%s' due to BF match in random routing for %s\n",
+                    GNUNET_i2s (&pos->id), GNUNET_h2s (key));
+        pos = pos->next;
+        continue;               /* Ignore bloomfiltered peers */
+      }
+      count++;
+      pos = pos->next;
+    }
+  }
+  if (0 == count)               /* No peers to select from! */
+  {
+    GNUNET_STATISTICS_update (GDS_stats,
+                              gettext_noop ("# Peer selection failed"), 1,
+                              GNUNET_NO);
+    return NULL;
+  }
+  /* Now actually choose a peer */
+  selected = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, count);
+  count = 0;
+  for (bc = 0; bc <= closest_bucket; bc++)
+  {
+    for (pos = k_buckets[bc].head; ((pos != NULL) && (count < bucket_size)); pos = pos->next)
+    {
+      GNUNET_CRYPTO_hash (&pos->id,
+                          sizeof (struct GNUNET_PeerIdentity),
+                          &phash);
+      if ((bloom != NULL) &&
+          (GNUNET_YES ==
+           GNUNET_CONTAINER_bloomfilter_test (bloom, &phash)))
+      {
+        continue;               /* Ignore bloomfiltered peers */
+      }
+      if (0 == selected--)
+        return pos;
+    }
+  }
+  GNUNET_break (0);
+  return NULL;
+}
+
+
+/**
+ * Compute the set of peers that the given request should be
+ * forwarded to.
+ *
+ * @param key routing key
+ * @param bloom bloom filter excluding peers as targets, all selected
+ *        peers will be added to the bloom filter
+ * @param hop_count number of hops the request has traversed so far
+ * @param target_replication desired number of replicas
+ * @param targets where to store an array of target peers (to be
+ *         free'd by the caller)
+ * @return number of peers returned in 'targets'.
+ */
+static unsigned int
+get_target_peers (const struct GNUNET_HashCode *key,
+                  struct GNUNET_CONTAINER_BloomFilter *bloom,
+                  uint32_t hop_count, uint32_t target_replication,
+                  struct PeerInfo ***targets)
+{
+  unsigned int ret;
+  unsigned int off;
+  struct PeerInfo **rtargets;
+  struct PeerInfo *nxt;
+  struct GNUNET_HashCode nhash;
+
+  GNUNET_assert (NULL != bloom);
+  ret = get_forward_count (hop_count, target_replication);
+  if (0 == ret)
+  {
+    *targets = NULL;
+    return 0;
+  }
+  rtargets = GNUNET_malloc (sizeof (struct PeerInfo *) * ret);
+  for (off = 0; off < ret; off++)
+  {
+    nxt = select_peer (key, bloom, hop_count);
+    if (NULL == nxt)
+      break;
+    rtargets[off] = nxt;
+    GNUNET_CRYPTO_hash (&nxt->id,
+                        sizeof (struct GNUNET_PeerIdentity),
+                        &nhash);
+    GNUNET_break (GNUNET_NO ==
+                  GNUNET_CONTAINER_bloomfilter_test (bloom,
+                                                     &nhash));
+    GNUNET_CONTAINER_bloomfilter_add (bloom, &nhash);
+  }
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Selected %u/%u peers at hop %u for %s (target was %u)\n", off,
+              GNUNET_CONTAINER_multipeermap_size (all_known_peers),
+              (unsigned int) hop_count, GNUNET_h2s (key), ret);
+  if (0 == off)
+  {
+    GNUNET_free (rtargets);
+    *targets = NULL;
+    return 0;
+  }
+  *targets = rtargets;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Forwarding query `%s' to %u peers (goal was %u peers)\n",
+              GNUNET_h2s (key),
+              off,
+              ret);
+  return off;
+}
+
+
+/**
+ * Perform a PUT operation.   Forwards the given request to other
+ * peers.   Does not store the data locally.  Does not give the
+ * data to local clients.  May do nothing if this is the only
+ * peer in the network (or if we are the closest peer in the
+ * network).
+ *
+ * @param type type of the block
+ * @param options routing options
+ * @param desired_replication_level desired replication count
+ * @param expiration_time when does the content expire
+ * @param hop_count how many hops has this message traversed so far
+ * @param bf Bloom filter of peers this PUT has already traversed
+ * @param key key for the content
+ * @param put_path_length number of entries in @a put_path
+ * @param put_path peers this request has traversed so far (if tracked)
+ * @param data payload to store
+ * @param data_size number of bytes in @a data
+ */
+void
+GDS_NEIGHBOURS_handle_put (enum GNUNET_BLOCK_Type type,
+                           enum GNUNET_DHT_RouteOption options,
+                           uint32_t desired_replication_level,
+                           struct GNUNET_TIME_Absolute expiration_time,
+                           uint32_t hop_count,
+                           struct GNUNET_CONTAINER_BloomFilter *bf,
+                           const struct GNUNET_HashCode *key,
+                           unsigned int put_path_length,
+                           struct GNUNET_PeerIdentity *put_path,
+                           const void *data, size_t data_size)
+{
+  unsigned int target_count;
+  unsigned int i;
+  struct PeerInfo **targets;
+  struct PeerInfo *target;
+  struct P2PPendingMessage *pending;
+  size_t msize;
+  struct PeerPutMessage *ppm;
+  struct GNUNET_PeerIdentity *pp;
+  struct GNUNET_HashCode thash;
+
+  GNUNET_assert (NULL != bf);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Adding myself (%s) to PUT bloomfilter for %s\n",
+              GNUNET_i2s (&my_identity), GNUNET_h2s (key));
+  GNUNET_CONTAINER_bloomfilter_add (bf, &my_identity_hash);
+  GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# PUT requests routed"),
+                            1, GNUNET_NO);
+  target_count =
+      get_target_peers (key, bf, hop_count, desired_replication_level,
+                        &targets);
+  if (0 == target_count)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "Routing PUT for %s terminates after %u hops at %s\n",
+                GNUNET_h2s (key), (unsigned int) hop_count,
+                GNUNET_i2s (&my_identity));
+    return;
+  }
+  msize =
+      put_path_length * sizeof (struct GNUNET_PeerIdentity) + data_size +
+      sizeof (struct PeerPutMessage);
+  if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
+  {
+    put_path_length = 0;
+    msize = data_size + sizeof (struct PeerPutMessage);
+  }
+  if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
+  {
+    GNUNET_break (0);
+    GNUNET_free (targets);
+    return;
+  }
+  GNUNET_STATISTICS_update (GDS_stats,
+                            gettext_noop
+                            ("# PUT messages queued for transmission"),
+                            target_count, GNUNET_NO);
+  for (i = 0; i < target_count; i++)
+  {
+    target = targets[i];
+    if (target->pending_count >= MAXIMUM_PENDING_PER_PEER)
+    {
+      GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
+                                1, GNUNET_NO);
+      continue; /* skip */
+    }
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "Routing PUT for %s after %u hops to %s\n", GNUNET_h2s (key),
+                (unsigned int) hop_count, GNUNET_i2s (&target->id));
+    pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
+    pending->importance = 0;    /* FIXME */
+    pending->timeout = expiration_time;
+    ppm = (struct PeerPutMessage *) &pending[1];
+    pending->msg = &ppm->header;
+    ppm->header.size = htons (msize);
+    ppm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_PUT);
+    ppm->options = htonl (options);
+    ppm->type = htonl (type);
+    ppm->hop_count = htonl (hop_count + 1);
+    ppm->desired_replication_level = htonl (desired_replication_level);
+    ppm->put_path_length = htonl (put_path_length);
+    ppm->expiration_time = GNUNET_TIME_absolute_hton (expiration_time);
+    GNUNET_CRYPTO_hash (&target->id,
+                        sizeof (struct GNUNET_PeerIdentity),
+                        &thash);
+    GNUNET_break (GNUNET_YES ==
+                  GNUNET_CONTAINER_bloomfilter_test (bf,
+                                                     &thash));
+    GNUNET_assert (GNUNET_OK ==
+                   GNUNET_CONTAINER_bloomfilter_get_raw_data (bf,
+                                                              ppm->bloomfilter,
+                                                              DHT_BLOOM_SIZE));
+    ppm->key = *key;
+    pp = (struct GNUNET_PeerIdentity *) &ppm[1];
+    memcpy (pp, put_path,
+            sizeof (struct GNUNET_PeerIdentity) * put_path_length);
+    memcpy (&pp[put_path_length], data, data_size);
+    GNUNET_CONTAINER_DLL_insert_tail (target->head, target->tail, pending);
+    target->pending_count++;
+    process_peer_queue (target);
+  }
+  GNUNET_free (targets);
+}
+
+
+/**
+ * Perform a GET operation.  Forwards the given request to other
+ * peers.  Does not lookup the key locally.  May do nothing if this is
+ * the only peer in the network (or if we are the closest peer in the
+ * network).
+ *
+ * @param type type of the block
+ * @param options routing options
+ * @param desired_replication_level desired replication count
+ * @param hop_count how many hops did this request traverse so far?
+ * @param key key for the content
+ * @param xquery extended query
+ * @param xquery_size number of bytes in @a xquery
+ * @param reply_bf bloomfilter to filter duplicates
+ * @param reply_bf_mutator mutator for @a reply_bf
+ * @param peer_bf filter for peers not to select (again)
+ */
+void
+GDS_NEIGHBOURS_handle_get (enum GNUNET_BLOCK_Type type,
+                           enum GNUNET_DHT_RouteOption options,
+                           uint32_t desired_replication_level,
+                           uint32_t hop_count, const struct GNUNET_HashCode * key,
+                           const void *xquery, size_t xquery_size,
+                           const struct GNUNET_CONTAINER_BloomFilter *reply_bf,
+                           uint32_t reply_bf_mutator,
+                           struct GNUNET_CONTAINER_BloomFilter *peer_bf)
+{
+  unsigned int target_count;
+  unsigned int i;
+  struct PeerInfo **targets;
+  struct PeerInfo *target;
+  struct P2PPendingMessage *pending;
+  size_t msize;
+  struct PeerGetMessage *pgm;
+  char *xq;
+  size_t reply_bf_size;
+  struct GNUNET_HashCode thash;
+
+  GNUNET_assert (NULL != peer_bf);
+  GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# GET requests routed"),
+                            1, GNUNET_NO);
+  target_count =
+      get_target_peers (key, peer_bf, hop_count, desired_replication_level,
+                        &targets);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Adding myself (%s) to GET bloomfilter for %s\n",
+              GNUNET_i2s (&my_identity), GNUNET_h2s (key));
+  GNUNET_CONTAINER_bloomfilter_add (peer_bf, &my_identity_hash);
+  if (0 == target_count)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "Routing GET for %s terminates after %u hops at %s\n",
+                GNUNET_h2s (key), (unsigned int) hop_count,
+                GNUNET_i2s (&my_identity));
+    return;
+  }
+  reply_bf_size = GNUNET_CONTAINER_bloomfilter_get_size (reply_bf);
+  msize = xquery_size + sizeof (struct PeerGetMessage) + reply_bf_size;
+  if (msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
+  {
+    GNUNET_break (0);
+    GNUNET_free (targets);
+    return;
+  }
+  GNUNET_STATISTICS_update (GDS_stats,
+                            gettext_noop
+                            ("# GET messages queued for transmission"),
+                            target_count, GNUNET_NO);
+  /* forward request */
+  for (i = 0; i < target_count; i++)
+  {
+    target = targets[i];
+    if (target->pending_count >= MAXIMUM_PENDING_PER_PEER)
+    {
+      GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
+                                1, GNUNET_NO);
+      continue; /* skip */
+    }
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "Routing GET for %s after %u hops to %s\n", GNUNET_h2s (key),
+                (unsigned int) hop_count, GNUNET_i2s (&target->id));
+    pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
+    pending->importance = 0;    /* FIXME */
+    pending->timeout = GNUNET_TIME_relative_to_absolute (GET_TIMEOUT);
+    pgm = (struct PeerGetMessage *) &pending[1];
+    pending->msg = &pgm->header;
+    pgm->header.size = htons (msize);
+    pgm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_GET);
+    pgm->options = htonl (options);
+    pgm->type = htonl (type);
+    pgm->hop_count = htonl (hop_count + 1);
+    pgm->desired_replication_level = htonl (desired_replication_level);
+    pgm->xquery_size = htonl (xquery_size);
+    pgm->bf_mutator = reply_bf_mutator;
+    GNUNET_CRYPTO_hash (&target->id,
+                        sizeof (struct GNUNET_PeerIdentity),
+                        &thash);
+    GNUNET_break (GNUNET_YES ==
+                  GNUNET_CONTAINER_bloomfilter_test (peer_bf,
+                                                     &thash));
+    GNUNET_assert (GNUNET_OK ==
+                   GNUNET_CONTAINER_bloomfilter_get_raw_data (peer_bf,
+                                                              pgm->bloomfilter,
+                                                              DHT_BLOOM_SIZE));
+    pgm->key = *key;
+    xq = (char *) &pgm[1];
+    memcpy (xq, xquery, xquery_size);
+    if (NULL != reply_bf)
+      GNUNET_assert (GNUNET_OK ==
+                     GNUNET_CONTAINER_bloomfilter_get_raw_data (reply_bf,
+                                                                &xq
+                                                                [xquery_size],
+                                                                reply_bf_size));
+    GNUNET_CONTAINER_DLL_insert_tail (target->head, target->tail, pending);
+    target->pending_count++;
+    process_peer_queue (target);
+  }
+  GNUNET_free (targets);
+}
+
+
+/**
+ * Handle a reply (route to origin).  Only forwards the reply back to
+ * the given peer.  Does not do local caching or forwarding to local
+ * clients.
+ *
+ * @param target neighbour that should receive the block (if still connected)
+ * @param type type of the block
+ * @param expiration_time when does the content expire
+ * @param key key for the content
+ * @param put_path_length number of entries in @a put_path
+ * @param put_path peers the original PUT traversed (if tracked)
+ * @param get_path_length number of entries in @a get_path
+ * @param get_path peers this reply has traversed so far (if tracked)
+ * @param data payload of the reply
+ * @param data_size number of bytes in @a data
+ */
+void
+GDS_NEIGHBOURS_handle_reply (const struct GNUNET_PeerIdentity *target,
+                             enum GNUNET_BLOCK_Type type,
+                             struct GNUNET_TIME_Absolute expiration_time,
+                             const struct GNUNET_HashCode * key,
+                             unsigned int put_path_length,
+                             const struct GNUNET_PeerIdentity *put_path,
+                             unsigned int get_path_length,
+                             const struct GNUNET_PeerIdentity *get_path,
+                             const void *data, size_t data_size)
+{
+  struct PeerInfo *pi;
+  struct P2PPendingMessage *pending;
+  size_t msize;
+  struct PeerResultMessage *prm;
+  struct GNUNET_PeerIdentity *paths;
+
+  msize =
+      data_size + sizeof (struct PeerResultMessage) + (get_path_length +
+                                                       put_path_length) *
+      sizeof (struct GNUNET_PeerIdentity);
+  if ((msize >= GNUNET_SERVER_MAX_MESSAGE_SIZE) ||
+      (get_path_length >
+       GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
+      (put_path_length >
+       GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
+      (data_size > GNUNET_SERVER_MAX_MESSAGE_SIZE))
+  {
+    GNUNET_break (0);
+    return;
+  }
+  pi = GNUNET_CONTAINER_multipeermap_get (all_known_peers, target);
+  if (NULL == pi)
+  {
+    /* peer disconnected in the meantime, drop reply */
+    return;
+  }
+  if (pi->pending_count >= MAXIMUM_PENDING_PER_PEER)
+  {
+    /* skip */
+    GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P messages dropped due to full queue"),
+                              1, GNUNET_NO);
+    return;
+  }
+
+  GNUNET_STATISTICS_update (GDS_stats,
+                            gettext_noop
+                            ("# RESULT messages queued for transmission"), 1,
+                            GNUNET_NO);
+  pending = GNUNET_malloc (sizeof (struct P2PPendingMessage) + msize);
+  pending->importance = 0;      /* FIXME */
+  pending->timeout = expiration_time;
+  prm = (struct PeerResultMessage *) &pending[1];
+  pending->msg = &prm->header;
+  prm->header.size = htons (msize);
+  prm->header.type = htons (GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT);
+  prm->type = htonl (type);
+  prm->put_path_length = htonl (put_path_length);
+  prm->get_path_length = htonl (get_path_length);
+  prm->expiration_time = GNUNET_TIME_absolute_hton (expiration_time);
+  prm->key = *key;
+  paths = (struct GNUNET_PeerIdentity *) &prm[1];
+  memcpy (paths, put_path,
+          put_path_length * sizeof (struct GNUNET_PeerIdentity));
+  memcpy (&paths[put_path_length], get_path,
+          get_path_length * sizeof (struct GNUNET_PeerIdentity));
+  memcpy (&paths[put_path_length + get_path_length], data, data_size);
+  GNUNET_CONTAINER_DLL_insert (pi->head, pi->tail, pending);
+  pi->pending_count++;
+  process_peer_queue (pi);
+}
+
+
+/**
+ * To be called on core init/fail.
+ *
+ * @param cls service closure
+ * @param identity the public identity of this peer
+ */
+static void
+core_init (void *cls,
+           const struct GNUNET_PeerIdentity *identity)
+{
+  my_identity = *identity;
+  GNUNET_CRYPTO_hash (identity,
+                      sizeof (struct GNUNET_PeerIdentity),
+                      &my_identity_hash);
+}
+
+
+/**
+ * Core handler for p2p put requests.
+ *
+ * @param cls closure
+ * @param peer sender of the request
+ * @param message message
+ * @param peer peer identity this notification is about
+ * @return #GNUNET_OK to keep the connection open,
+ *         #GNUNET_SYSERR to close it (signal serious error)
+ */
+static int
+handle_dht_p2p_put (void *cls,
+                    const struct GNUNET_PeerIdentity *peer,
+                    const struct GNUNET_MessageHeader *message)
+{
+  const struct PeerPutMessage *put;
+  const struct GNUNET_PeerIdentity *put_path;
+  const void *payload;
+  uint32_t putlen;
+  uint16_t msize;
+  size_t payload_size;
+  enum GNUNET_DHT_RouteOption options;
+  struct GNUNET_CONTAINER_BloomFilter *bf;
+  struct GNUNET_HashCode test_key;
+  struct GNUNET_HashCode phash;
+
+  msize = ntohs (message->size);
+  if (msize < sizeof (struct PeerPutMessage))
+  {
+    GNUNET_break_op (0);
+    return GNUNET_YES;
+  }
+  put = (const struct PeerPutMessage *) message;
+  putlen = ntohl (put->put_path_length);
+  if ((msize <
+       sizeof (struct PeerPutMessage) +
+       putlen * sizeof (struct GNUNET_PeerIdentity)) ||
+      (putlen >
+       GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
+  {
+    GNUNET_break_op (0);
+    return GNUNET_YES;
+  }
+  GNUNET_STATISTICS_update (GDS_stats,
+                            gettext_noop ("# P2P PUT requests received"), 1,
+                            GNUNET_NO);
+  GNUNET_STATISTICS_update (GDS_stats,
+                            gettext_noop ("# P2P PUT bytes received"), msize,
+                            GNUNET_NO);
+  put_path = (const struct GNUNET_PeerIdentity *) &put[1];
+  payload = &put_path[putlen];
+  options = ntohl (put->options);
+  payload_size =
+      msize - (sizeof (struct PeerPutMessage) +
+               putlen * sizeof (struct GNUNET_PeerIdentity));
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "PUT for `%s' from %s\n",
+              GNUNET_h2s (&put->key), GNUNET_i2s (peer));
+  GNUNET_CRYPTO_hash (peer, sizeof (struct GNUNET_PeerIdentity), &phash);
+  if (GNUNET_YES == log_route_details_stderr)
+  {
+    char *tmp;
+
+    tmp = GNUNET_strdup (GNUNET_i2s (&my_identity));
+    LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG,
+                 "XDHT PUT %s: %s->%s (%u, %u=>%u)\n",
+                 GNUNET_h2s (&put->key), GNUNET_i2s (peer), tmp,
+                 ntohl(put->hop_count),
+                 GNUNET_CRYPTO_hash_matching_bits (&phash, &put->key),
+                 GNUNET_CRYPTO_hash_matching_bits (&my_identity_hash, &put->key)
+                );
+    GNUNET_free (tmp);
+  }
+  switch (GNUNET_BLOCK_get_key
+          (GDS_block_context, ntohl (put->type), payload, payload_size,
+           &test_key))
+  {
+  case GNUNET_YES:
+    if (0 != memcmp (&test_key, &put->key, sizeof (struct GNUNET_HashCode)))
+    {
+      char *put_s = GNUNET_strdup (GNUNET_h2s (&put->key));
+      GNUNET_break_op (0);
+      GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                  "PUT with key `%s' for block with key %s\n",
+                  put_s, GNUNET_h2s (&test_key));
+      GNUNET_free (put_s);
+      return GNUNET_YES;
+    }
+    break;
+  case GNUNET_NO:
+    GNUNET_break_op (0);
+    return GNUNET_YES;
+  case GNUNET_SYSERR:
+    /* cannot verify, good luck */
+    break;
+  }
+  if (ntohl (put->type) == GNUNET_BLOCK_TYPE_REGEX) /* FIXME: do for all tpyes */
+  {
+    switch (GNUNET_BLOCK_evaluate (GDS_block_context,
+                                   ntohl (put->type),
+                                   NULL,    /* query */
+                                   NULL, 0, /* bloom filer */
+                                   NULL, 0, /* xquery */
+                                   payload, payload_size))
+    {
+    case GNUNET_BLOCK_EVALUATION_OK_MORE:
+    case GNUNET_BLOCK_EVALUATION_OK_LAST:
+      break;
+
+    case GNUNET_BLOCK_EVALUATION_OK_DUPLICATE:
+    case GNUNET_BLOCK_EVALUATION_RESULT_INVALID:
+    case GNUNET_BLOCK_EVALUATION_RESULT_IRRELEVANT:
+    case GNUNET_BLOCK_EVALUATION_REQUEST_VALID:
+    case GNUNET_BLOCK_EVALUATION_REQUEST_INVALID:
+    case GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED:
+    default:
+      GNUNET_break_op (0);
+      return GNUNET_OK;
+    }
+  }
+
+  bf = GNUNET_CONTAINER_bloomfilter_init (put->bloomfilter, DHT_BLOOM_SIZE,
+                                          GNUNET_CONSTANTS_BLOOMFILTER_K);
+  GNUNET_break_op (GNUNET_YES ==
+                   GNUNET_CONTAINER_bloomfilter_test (bf, &phash));
+  {
+    struct GNUNET_PeerIdentity pp[putlen + 1];
+
+    /* extend 'put path' by sender */
+    if (0 != (options & GNUNET_DHT_RO_RECORD_ROUTE))
+    {
+      memcpy (pp, put_path, putlen * sizeof (struct GNUNET_PeerIdentity));
+      pp[putlen] = *peer;
+      putlen++;
+    }
+    else
+      putlen = 0;
+
+    /* give to local clients */
+    GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (put->expiration_time),
+                              &put->key, 0, NULL, putlen, pp, ntohl (put->type),
+                              payload_size, payload);
+    /* store locally */
+    if ((0 != (options & GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE)) ||
+        (am_closest_peer (&put->key, bf)))
+      GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh
+                                (put->expiration_time), &put->key, putlen, pp,
+                                ntohl (put->type), payload_size, payload);
+    /* route to other peers */
+    GDS_NEIGHBOURS_handle_put (ntohl (put->type), options,
+                               ntohl (put->desired_replication_level),
+                               GNUNET_TIME_absolute_ntoh (put->expiration_time),
+                               ntohl (put->hop_count), bf, &put->key, putlen,
+                               pp, payload, payload_size);
+    /* notify monitoring clients */
+    GDS_CLIENTS_process_put (options,
+                             ntohl (put->type),
+                             ntohl (put->hop_count),
+                             ntohl (put->desired_replication_level),
+                             putlen, pp,
+                             GNUNET_TIME_absolute_ntoh (put->expiration_time),
+                             &put->key,
+                             payload,
+                             payload_size);
+  }
+  GNUNET_CONTAINER_bloomfilter_free (bf);
+  return GNUNET_YES;
+}
+
+
+/**
+ * We have received a FIND PEER request.  Send matching
+ * HELLOs back.
+ *
+ * @param sender sender of the FIND PEER request
+ * @param key peers close to this key are desired
+ * @param bf peers matching this bf are excluded
+ * @param bf_mutator mutator for bf
+ */
+static void
+handle_find_peer (const struct GNUNET_PeerIdentity *sender,
+                  const struct GNUNET_HashCode * key,
+                  struct GNUNET_CONTAINER_BloomFilter *bf, uint32_t bf_mutator)
+{
+  int bucket_idx;
+  struct PeerBucket *bucket;
+  struct PeerInfo *peer;
+  unsigned int choice;
+  struct GNUNET_HashCode phash;
+  struct GNUNET_HashCode mhash;
+  const struct GNUNET_HELLO_Message *hello;
+
+  /* first, check about our own HELLO */
+  if (NULL != GDS_my_hello)
+  {
+    GNUNET_BLOCK_mingle_hash (&my_identity_hash, bf_mutator, &mhash);
+    if ((NULL == bf) ||
+        (GNUNET_YES != GNUNET_CONTAINER_bloomfilter_test (bf, &mhash)))
+    {
+      GDS_NEIGHBOURS_handle_reply (sender, GNUNET_BLOCK_TYPE_DHT_HELLO,
+                                   GNUNET_TIME_relative_to_absolute
+                                   (hello_expiration),
+                                   key, 0, NULL, 0, NULL, GDS_my_hello,
+                                   GNUNET_HELLO_size ((const struct
+                                                       GNUNET_HELLO_Message *)
+                                                      GDS_my_hello));
+    }
+    else
+    {
+      GNUNET_STATISTICS_update (GDS_stats,
+                                gettext_noop
+                                ("# FIND PEER requests ignored due to Bloomfilter"),
+                                1, GNUNET_NO);
+    }
+  }
+  else
+  {
+    GNUNET_STATISTICS_update (GDS_stats,
+                              gettext_noop
+                              ("# FIND PEER requests ignored due to lack of HELLO"),
+                              1, GNUNET_NO);
+  }
+
+  /* then, also consider sending a random HELLO from the closest bucket */
+  if (0 == memcmp (&my_identity_hash, key, sizeof (struct GNUNET_HashCode)))
+    bucket_idx = closest_bucket;
+  else
+    bucket_idx = GNUNET_MIN (closest_bucket, find_bucket (key));
+  if (bucket_idx == GNUNET_SYSERR)
+    return;
+  bucket = &k_buckets[bucket_idx];
+  if (bucket->peers_size == 0)
+    return;
+  choice =
+      GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, bucket->peers_size);
+  peer = bucket->head;
+  while (choice > 0)
+  {
+    GNUNET_assert (NULL != peer);
+    peer = peer->next;
+    choice--;
+  }
+  choice = bucket->peers_size;
+  do
+  {
+    peer = peer->next;
+    if (choice-- == 0)
+      return;                   /* no non-masked peer available */
+    if (peer == NULL)
+      peer = bucket->head;
+    GNUNET_CRYPTO_hash (&peer->id, sizeof (struct GNUNET_PeerIdentity), &phash);
+    GNUNET_BLOCK_mingle_hash (&phash, bf_mutator, &mhash);
+    hello = GDS_HELLO_get (&peer->id);
+  }
+  while ((hello == NULL) ||
+         (GNUNET_YES == GNUNET_CONTAINER_bloomfilter_test (bf, &mhash)));
+  GDS_NEIGHBOURS_handle_reply (sender, GNUNET_BLOCK_TYPE_DHT_HELLO,
+                               GNUNET_TIME_relative_to_absolute
+                               (GNUNET_CONSTANTS_HELLO_ADDRESS_EXPIRATION), key,
+                               0, NULL, 0, NULL, hello,
+                               GNUNET_HELLO_size (hello));
+}
+
+
+/**
+ * Core handler for p2p get requests.
+ *
+ * @param cls closure
+ * @param peer sender of the request
+ * @param message message
+ * @return #GNUNET_OK to keep the connection open,
+ *         #GNUNET_SYSERR to close it (signal serious error)
+ */
+static int
+handle_dht_p2p_get (void *cls, const struct GNUNET_PeerIdentity *peer,
+                    const struct GNUNET_MessageHeader *message)
+{
+  struct PeerGetMessage *get;
+  uint32_t xquery_size;
+  size_t reply_bf_size;
+  uint16_t msize;
+  enum GNUNET_BLOCK_Type type;
+  enum GNUNET_DHT_RouteOption options;
+  enum GNUNET_BLOCK_EvaluationResult eval;
+  struct GNUNET_CONTAINER_BloomFilter *reply_bf;
+  struct GNUNET_CONTAINER_BloomFilter *peer_bf;
+  const char *xquery;
+  struct GNUNET_HashCode phash;
+
+  GNUNET_break (0 !=
+                memcmp (peer, &my_identity,
+                        sizeof (struct GNUNET_PeerIdentity)));
+  /* parse and validate message */
+  msize = ntohs (message->size);
+  if (msize < sizeof (struct PeerGetMessage))
+  {
+    GNUNET_break_op (0);
+    return GNUNET_YES;
+  }
+  get = (struct PeerGetMessage *) message;
+  xquery_size = ntohl (get->xquery_size);
+  if (msize < sizeof (struct PeerGetMessage) + xquery_size)
+  {
+    GNUNET_break_op (0);
+    return GNUNET_YES;
+  }
+  reply_bf_size = msize - (sizeof (struct PeerGetMessage) + xquery_size);
+  type = ntohl (get->type);
+  options = ntohl (get->options);
+  xquery = (const char *) &get[1];
+  reply_bf = NULL;
+  GNUNET_STATISTICS_update (GDS_stats,
+                            gettext_noop ("# P2P GET requests received"), 1,
+                            GNUNET_NO);
+  GNUNET_STATISTICS_update (GDS_stats,
+                            gettext_noop ("# P2P GET bytes received"), msize,
+                            GNUNET_NO);
+  GNUNET_CRYPTO_hash (peer, sizeof (struct GNUNET_PeerIdentity), &phash);
+  if (GNUNET_YES == log_route_details_stderr)
+  {
+    char *tmp;
+
+    tmp = GNUNET_strdup (GNUNET_i2s (&my_identity));
+    LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG,
+                 "XDHT GET %s: %s->%s (%u, %u=>%u) xq: %.*s\n",
+                 GNUNET_h2s (&get->key), GNUNET_i2s (peer), tmp,
+                 ntohl(get->hop_count),
+                 GNUNET_CRYPTO_hash_matching_bits (&phash, &get->key),
+                 GNUNET_CRYPTO_hash_matching_bits (&my_identity_hash, &get->key),
+                 ntohl(get->xquery_size), xquery
+                );
+    GNUNET_free (tmp);
+  }
+
+  if (reply_bf_size > 0)
+    reply_bf =
+        GNUNET_CONTAINER_bloomfilter_init (&xquery[xquery_size], reply_bf_size,
+                                           GNUNET_CONSTANTS_BLOOMFILTER_K);
+  eval =
+      GNUNET_BLOCK_evaluate (GDS_block_context, type, &get->key, &reply_bf,
+                             get->bf_mutator, xquery, xquery_size, NULL, 0);
+  if (eval != GNUNET_BLOCK_EVALUATION_REQUEST_VALID)
+  {
+    /* request invalid or block type not supported */
+    GNUNET_break_op (eval == GNUNET_BLOCK_EVALUATION_TYPE_NOT_SUPPORTED);
+    if (NULL != reply_bf)
+      GNUNET_CONTAINER_bloomfilter_free (reply_bf);
+    return GNUNET_YES;
+  }
+  peer_bf =
+      GNUNET_CONTAINER_bloomfilter_init (get->bloomfilter, DHT_BLOOM_SIZE,
+                                         GNUNET_CONSTANTS_BLOOMFILTER_K);
+  GNUNET_break_op (GNUNET_YES ==
+                   GNUNET_CONTAINER_bloomfilter_test (peer_bf,
+                                                      &phash));
+  /* remember request for routing replies */
+  GDS_ROUTING_add (peer, type, options, &get->key, xquery, xquery_size,
+                   reply_bf, get->bf_mutator);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "GET for %s at %s after %u hops\n",
+              GNUNET_h2s (&get->key), GNUNET_i2s (&my_identity),
+              (unsigned int) ntohl (get->hop_count));
+  /* local lookup (this may update the reply_bf) */
+  if ((0 != (options & GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE)) ||
+      (am_closest_peer (&get->key, peer_bf)))
+  {
+    if ((0 != (options & GNUNET_DHT_RO_FIND_PEER)))
+    {
+      GNUNET_STATISTICS_update (GDS_stats,
+                                gettext_noop
+                                ("# P2P FIND PEER requests processed"), 1,
+                                GNUNET_NO);
+      handle_find_peer (peer, &get->key, reply_bf, get->bf_mutator);
+    }
+    else
+    {
+      eval =
+          GDS_DATACACHE_handle_get (&get->key, type, xquery, xquery_size,
+                                    &reply_bf, get->bf_mutator);
+    }
+  }
+  else
+  {
+    GNUNET_STATISTICS_update (GDS_stats,
+                              gettext_noop ("# P2P GET requests ONLY routed"),
+                              1, GNUNET_NO);
+  }
+
+  GDS_CLIENTS_process_get (options,
+                           type,
+                           ntohl(get->hop_count),
+                           ntohl(get->desired_replication_level),
+                           0, NULL,
+                           &get->key);
+
+  /* P2P forwarding */
+  if (eval != GNUNET_BLOCK_EVALUATION_OK_LAST)
+    GDS_NEIGHBOURS_handle_get (type, options,
+                               ntohl (get->desired_replication_level),
+                               ntohl (get->hop_count), &get->key, xquery,
+                               xquery_size, reply_bf, get->bf_mutator, peer_bf);
+  /* clean up */
+  if (NULL != reply_bf)
+    GNUNET_CONTAINER_bloomfilter_free (reply_bf);
+  GNUNET_CONTAINER_bloomfilter_free (peer_bf);
+  return GNUNET_YES;
+}
+
+
+/**
+ * Core handler for p2p result messages.
+ *
+ * @param cls closure
+ * @param message message
+ * @param peer peer identity this notification is about
+ * @return #GNUNET_YES (do not cut p2p connection)
+ */
+static int
+handle_dht_p2p_result (void *cls, const struct GNUNET_PeerIdentity *peer,
+                       const struct GNUNET_MessageHeader *message)
+{
+  const struct PeerResultMessage *prm;
+  const struct GNUNET_PeerIdentity *put_path;
+  const struct GNUNET_PeerIdentity *get_path;
+  const void *data;
+  uint32_t get_path_length;
+  uint32_t put_path_length;
+  uint16_t msize;
+  size_t data_size;
+  enum GNUNET_BLOCK_Type type;
+
+  /* parse and validate message */
+  msize = ntohs (message->size);
+  if (msize < sizeof (struct PeerResultMessage))
+  {
+    GNUNET_break_op (0);
+    return GNUNET_YES;
+  }
+  prm = (struct PeerResultMessage *) message;
+  put_path_length = ntohl (prm->put_path_length);
+  get_path_length = ntohl (prm->get_path_length);
+  if ((msize <
+       sizeof (struct PeerResultMessage) + (get_path_length +
+                                            put_path_length) *
+       sizeof (struct GNUNET_PeerIdentity)) ||
+      (get_path_length >
+       GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)) ||
+      (put_path_length >
+       GNUNET_SERVER_MAX_MESSAGE_SIZE / sizeof (struct GNUNET_PeerIdentity)))
+  {
+    GNUNET_break_op (0);
+    return GNUNET_YES;
+  }
+  put_path = (const struct GNUNET_PeerIdentity *) &prm[1];
+  get_path = &put_path[put_path_length];
+  type = ntohl (prm->type);
+  data = (const void *) &get_path[get_path_length];
+  data_size =
+      msize - (sizeof (struct PeerResultMessage) +
+               (get_path_length +
+                put_path_length) * sizeof (struct GNUNET_PeerIdentity));
+  GNUNET_STATISTICS_update (GDS_stats, gettext_noop ("# P2P RESULTS received"),
+                            1, GNUNET_NO);
+  GNUNET_STATISTICS_update (GDS_stats,
+                            gettext_noop ("# P2P RESULT bytes received"),
+                            msize, GNUNET_NO);
+  if (GNUNET_YES == log_route_details_stderr)
+  {
+    char *tmp;
+
+    tmp = GNUNET_strdup (GNUNET_i2s (&my_identity));
+    LOG_TRAFFIC (GNUNET_ERROR_TYPE_DEBUG, "XDHT RESULT %s: %s->%s (%u)\n",
+                 GNUNET_h2s (&prm->key), GNUNET_i2s (peer), tmp,
+                 get_path_length + 1);
+    GNUNET_free (tmp);
+  }
+  /* if we got a HELLO, consider it for our own routing table */
+  if (type == GNUNET_BLOCK_TYPE_DHT_HELLO)
+  {
+    const struct GNUNET_MessageHeader *h;
+    struct GNUNET_PeerIdentity pid;
+    int bucket;
+
+    /* Should be a HELLO, validate and consider using it! */
+    if (data_size < sizeof (struct GNUNET_MessageHeader))
+    {
+      GNUNET_break_op (0);
+      return GNUNET_YES;
+    }
+    h = data;
+    if (data_size != ntohs (h->size))
+    {
+      GNUNET_break_op (0);
+      return GNUNET_YES;
+    }
+    if (GNUNET_OK !=
+        GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message *) h, &pid))
+    {
+      GNUNET_break_op (0);
+      return GNUNET_YES;
+    }
+    if ((GNUNET_YES != disable_try_connect) &&
+        0 != memcmp (&my_identity, &pid, sizeof (struct GNUNET_PeerIdentity)))
+    {
+      struct GNUNET_HashCode pid_hash;
+
+      GNUNET_CRYPTO_hash (&pid, sizeof (struct GNUNET_PeerIdentity), &pid_hash);
+      bucket = find_bucket (&pid_hash);
+      if ((bucket >= 0) &&
+          (k_buckets[bucket].peers_size < bucket_size) &&
+          (NULL != GDS_transport_handle))
+      {
+        GNUNET_TRANSPORT_offer_hello (GDS_transport_handle, h, NULL, NULL);
+        GNUNET_TRANSPORT_try_connect (GDS_transport_handle, &pid, NULL, NULL); /*FIXME TRY_CONNECT change */
+      }
+    }
+  }
+
+  /* append 'peer' to 'get_path' */
+  {
+    struct GNUNET_PeerIdentity xget_path[get_path_length + 1];
+
+    memcpy (xget_path, get_path,
+            get_path_length * sizeof (struct GNUNET_PeerIdentity));
+    xget_path[get_path_length] = *peer;
+    get_path_length++;
+
+    /* forward to local clients */
+    GDS_CLIENTS_handle_reply (GNUNET_TIME_absolute_ntoh (prm->expiration_time),
+                              &prm->key, get_path_length, xget_path,
+                              put_path_length, put_path, type, data_size, data);
+    GDS_CLIENTS_process_get_resp (type,
+                                  xget_path, get_path_length,
+                                  put_path, put_path_length,
+                                  GNUNET_TIME_absolute_ntoh (
+                                    prm->expiration_time),
+                                  &prm->key,
+                                  data,
+                                  data_size);
+    if (GNUNET_YES == cache_results)
+    {
+      struct GNUNET_PeerIdentity xput_path[get_path_length + 1 + put_path_length];
+
+      memcpy (xput_path, put_path, put_path_length * sizeof (struct GNUNET_PeerIdentity));
+      memcpy (&xput_path[put_path_length],
+              xget_path,
+              get_path_length * sizeof (struct GNUNET_PeerIdentity));
+
+      GDS_DATACACHE_handle_put (GNUNET_TIME_absolute_ntoh (prm->expiration_time),
+                                &prm->key,
+                                get_path_length + put_path_length, xput_path,
+                                type, data_size, data);
+    }
+    /* forward to other peers */
+    GDS_ROUTING_process (type, GNUNET_TIME_absolute_ntoh (prm->expiration_time),
+                         &prm->key, put_path_length, put_path, get_path_length,
+                         xget_path, data, data_size);
+  }
+
+  return GNUNET_YES;
+}
+
+
+/**
+ * Initialize neighbours subsystem.
+ *
+ * @return GNUNET_OK on success, GNUNET_SYSERR on error
+ */
+int
+GDS_NEIGHBOURS_init ()
+{
+  static struct GNUNET_CORE_MessageHandler core_handlers[] = {
+    {&handle_dht_p2p_get, GNUNET_MESSAGE_TYPE_DHT_P2P_GET, 0},
+    {&handle_dht_p2p_put, GNUNET_MESSAGE_TYPE_DHT_P2P_PUT, 0},
+    {&handle_dht_p2p_result, GNUNET_MESSAGE_TYPE_DHT_P2P_RESULT, 0},
+    {NULL, 0, 0}
+  };
+  unsigned long long temp_config_num;
+
+  disable_try_connect
+    = GNUNET_CONFIGURATION_get_value_yesno (GDS_cfg, "DHT", "DISABLE_TRY_CONNECT");
+  if (GNUNET_OK ==
+      GNUNET_CONFIGURATION_get_value_number (GDS_cfg, "DHT", "bucket_size",
+                                             &temp_config_num))
+    bucket_size = (unsigned int) temp_config_num;
+  cache_results
+    = GNUNET_CONFIGURATION_get_value_yesno (GDS_cfg, "DHT", "CACHE_RESULTS");
+
+  log_route_details_stderr =
+    (NULL != getenv("GNUNET_DHT_ROUTE_DEBUG")) ? GNUNET_YES : GNUNET_NO;
+  atsAPI = GNUNET_ATS_performance_init (GDS_cfg, NULL, NULL);
+  core_api =
+      GNUNET_CORE_connect (GDS_cfg, NULL, &core_init, &handle_core_connect,
+                           &handle_core_disconnect, NULL, GNUNET_NO, NULL,
+                           GNUNET_NO, core_handlers);
+  if (core_api == NULL)
+    return GNUNET_SYSERR;
+  all_known_peers = GNUNET_CONTAINER_multipeermap_create (256, GNUNET_NO);
+  return GNUNET_OK;
+}
+
+
+/**
+ * Shutdown neighbours subsystem.
+ */
+void
+GDS_NEIGHBOURS_done ()
+{
+  if (NULL == core_api)
+    return;
+  GNUNET_CORE_disconnect (core_api);
+  core_api = NULL;
+  GNUNET_ATS_performance_done (atsAPI);
+  atsAPI = NULL;
+  GNUNET_assert (0 == GNUNET_CONTAINER_multipeermap_size (all_known_peers));
+  GNUNET_CONTAINER_multipeermap_destroy (all_known_peers);
+  all_known_peers = NULL;
+  if (GNUNET_SCHEDULER_NO_TASK != find_peer_task)
+  {
+    GNUNET_SCHEDULER_cancel (find_peer_task);
+    find_peer_task = GNUNET_SCHEDULER_NO_TASK;
+  }
+}
+
+/**
+ * Get the ID of the local node.
+ *
+ * @return identity of the local node
+ */
+struct GNUNET_PeerIdentity *
+GDS_NEIGHBOURS_get_id ()
+{
+    return &my_identity;
+}
+
+
+/* end of gnunet-service-dht_neighbours.c */