- doc
[oweals/gnunet.git] / src / mesh / gnunet-service-mesh.c
index 626585c92e89b0f9399d1be36cfca28b46189bac..7ebe7d199d188696f36268b002a872fa3a1b1ae1 100644 (file)
@@ -1,6 +1,6 @@
 /*
      This file is part of GNUnet.
-     (C) 2001 - 2011 Christian Grothoff (and other contributing authors)
+     (C) 2001-2012 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
@@ -37,7 +37,6 @@
  * TODO:
  * - error reporting (CREATE/CHANGE/ADD/DEL?) -- new message!
  * - partial disconnect reporting -- same as error reporting?
- * - add vs create? change vs. keep-alive? same msg or different ones? -- thinking...
  * - add ping message
  * - relay corking down to core
  * - set ttl relative to tree depth
@@ -115,12 +114,11 @@ struct MeshData
   /** Tunnel it belongs to. */
   struct MeshTunnel *t;
 
-  /** In case of a multicast, task to allow a client to send more data if
-   * some neighbor is too slow. */
-  GNUNET_SCHEDULER_TaskIdentifier *task;
+  /** How many remaining neighbors still hav't got it. */
+  unsigned int reference_counter;
 
   /** How many remaining neighbors we need to send this to. */
-  unsigned int *reference_counter;
+  unsigned int total_out;
 
   /** Size of the data. */
   size_t data_len;
@@ -514,8 +512,9 @@ struct MeshTunnelChildInfo
   uint32_t bck_ack;
 
     /**
-     * Circular buffer pointing to MeshPeerQueue elements.
-     * Size determined by the tunnel queue size.
+     * Circular buffer pointing to MeshPeerQueue elements for all
+     * payload traffic going to this child.
+     * Size determined by the tunnel queue size (@c t->fwd_queue_max).
      */
   struct MeshPeerQueue **send_buffer;
 
@@ -769,6 +768,16 @@ struct MeshRegexSearchContext
      */
   struct MeshRegexSearchInfo *info;
 
+    /**
+     * We just want to look for one edge, the longer the better.
+     * Keep its length.
+     */
+  unsigned int longest_match;
+
+    /**
+     * Destination hash of the longest match.
+     */
+  struct GNUNET_HashCode hash;
 };
 
 /******************************************************************************/
@@ -796,6 +805,9 @@ mesh_debug (void *cls, int success)
 }
 #endif
 
+unsigned int debug_fwd_ack;
+unsigned int debug_bck_ack;
+
 #endif
 
 /******************************************************************************/
@@ -815,6 +827,12 @@ static long long unsigned int dht_replication_level;
 static long long unsigned int max_tunnels;
 static long long unsigned int max_msgs_queue;
 
+
+/**
+ * Hostkey generation context
+ */
+static struct GNUNET_CRYPTO_RsaKeyGenerationContext *keygen;
+
 /**
  * DLL with all the clients, head.
  */
@@ -1123,20 +1141,18 @@ tunnel_add_client (struct MeshTunnel *t, struct MeshClient *c);
 
 
 /**
- * Iterator over edges in a regex block retrieved from the DHT.
+ * Jump to the next edge, with the longest matching token.
  *
- * @param cls Closure.
- * @param token Token that follows to next state.
- * @param len Lenght of token.
- * @param key Hash of next state.
+ * @param block Block found in the DHT.
+ * @param size Size of the block.
+ * @param ctx Context of the search.
  *
  * @return GNUNET_YES if should keep iterating, GNUNET_NO otherwise.
  */
-static int
-regex_edge_iterator (void *cls,
-                     const char *token,
-                     size_t len,
-                     const struct GNUNET_HashCode *key);
+static void
+regex_next_edge (const struct MeshRegexBlock *block,
+                 size_t size,
+                 struct MeshRegexSearchContext *ctx);
 
 
 /**
@@ -1152,9 +1168,17 @@ regex_find_path (const struct GNUNET_HashCode *key,
 
 
 /**
- * Queue and pass message to core when possible.
+ * @brief Queue and pass message to core when possible.
+ * 
+ * If type is payload (UNICAST, TO_ORIGIN, MULTICAST) checks for queue status
+ * and accounts for it. In case the queue is full, the message is dropped and
+ * a break issued.
+ * 
+ * Otherwise, message is treated as internal and allowed to go regardless of 
+ * queue status.
  *
- * @param cls Closure (type dependant).
+ * @param cls Closure (@c type dependant). It will be used by queue_send to
+ *            build the message to be sent if not already prebuilt.
  * @param type Type of the message, 0 for a raw message.
  * @param size Size of the message.
  * @param dst Neighbor to send message to.
@@ -1238,8 +1262,7 @@ regex_result_iterator (void *cls,
                 ntohl(block->accepting));
 
   }
-  (void) GNUNET_MESH_regex_block_iterate (block, SIZE_MAX,
-                                          &regex_edge_iterator, ctx);
+  regex_next_edge(block, SIZE_MAX, ctx);
 
   return GNUNET_YES;
 }
@@ -1262,9 +1285,7 @@ regex_edge_iterator (void *cls,
                      const struct GNUNET_HashCode *key)
 {
   struct MeshRegexSearchContext *ctx = cls;
-  struct MeshRegexSearchContext *new_ctx;
   struct MeshRegexSearchInfo *info = ctx->info;
-  struct GNUNET_DHT_GetHandle *get_h;
   char *current;
   size_t current_len;
 
@@ -1288,40 +1309,93 @@ regex_edge_iterator (void *cls,
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*     Token doesn't match, END\n");
     return GNUNET_YES; // Token doesn't match
   }
+
+  if (len > ctx->longest_match)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*     Token is longer, KEEP\n");
+    ctx->longest_match = len;
+    ctx->hash = *key;
+  }
+  else
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*     Token is not longer, IGNORE\n");
+  }
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*    End of regex edge iterator\n");
+  return GNUNET_YES;
+}
+
+
+/**
+ * Jump to the next edge, with the longest matching token.
+ *
+ * @param block Block found in the DHT.
+ * @param size Size of the block.
+ * @param ctx Context of the search.
+ *
+ * @return GNUNET_YES if should keep iterating, GNUNET_NO otherwise.
+ */
+static void
+regex_next_edge (const struct MeshRegexBlock *block,
+                 size_t size,
+                 struct MeshRegexSearchContext *ctx)
+{
+  struct MeshRegexSearchContext *new_ctx;
+  struct MeshRegexSearchInfo *info = ctx->info;
+  struct GNUNET_DHT_GetHandle *get_h;
+
+  int result;
+
+  /* Find the longest match for the current string position, 
+   * among tokens in the given block */
+  ctx->longest_match = 0;
+  result = GNUNET_MESH_regex_block_iterate (block, size,
+                                            &regex_edge_iterator, ctx);
+  GNUNET_break (GNUNET_OK == result || SIZE_MAX == size);
+
+  /* Did anything match? */
+  if (0 == ctx->longest_match)
+    return;
+
   new_ctx = GNUNET_malloc (sizeof (struct MeshRegexSearchContext));
   new_ctx->info = info;
-  new_ctx->position = ctx->position + len;
+  new_ctx->position = ctx->position + ctx->longest_match;
   GNUNET_array_append (info->contexts, info->n_contexts, new_ctx);
+
+  /* Check whether we already have a DHT GET running for it */
   if (GNUNET_YES ==
-      GNUNET_CONTAINER_multihashmap_contains(info->dht_get_handles, key))
+      GNUNET_CONTAINER_multihashmap_contains(info->dht_get_handles, &ctx->hash))
   {
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*     GET running, END\n");
-    GNUNET_CONTAINER_multihashmap_get_multiple (info->dht_get_results, key,
+    GNUNET_CONTAINER_multihashmap_get_multiple (info->dht_get_results,
+                                                &ctx->hash,
                                                 &regex_result_iterator,
                                                 new_ctx);
-    return GNUNET_YES; // We are already looking for it
+    return; // We are already looking for it
   }
+
   /* Start search in DHT */
   get_h = 
       GNUNET_DHT_get_start (dht_handle,    /* handle */
                             GNUNET_BLOCK_TYPE_MESH_REGEX, /* type */
-                            key,     /* key to search */
+                            &ctx->hash,     /* key to search */
                             dht_replication_level, /* replication level */
                             GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE,
                             NULL,       /* xquery */ // FIXME BLOOMFILTER
                             0,     /* xquery bits */ // FIXME BLOOMFILTER SIZE
                             &dht_get_string_handler, new_ctx);
   if (GNUNET_OK !=
-      GNUNET_CONTAINER_multihashmap_put(info->dht_get_handles, key, get_h,
+      GNUNET_CONTAINER_multihashmap_put(info->dht_get_handles,
+                                        &ctx->hash,
+                                        get_h,
                                         GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
   {
     GNUNET_break (0);
-    return GNUNET_YES;
+    return;
   }
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*    End of regex edge iterator\n");
-  return GNUNET_YES;
 }
 
+
 /**
  * Iterator over hash map entries to cancel DHT GET requests after a
  * successful connect_by_string.
@@ -1376,8 +1450,11 @@ regex_free_result (void *cls,
  * @param edges edges leaving current state.
  */
 void
-regex_iterator (void *cls, const struct GNUNET_HashCode *key, const char *proof,
-                int accepting, unsigned int num_edges,
+regex_iterator (void *cls,
+                const struct GNUNET_HashCode *key,
+                const char *proof,
+                int accepting,
+                unsigned int num_edges,
                 const struct GNUNET_REGEX_Edge *edges)
 {
     struct MeshRegexBlock *block;
@@ -1632,6 +1709,7 @@ announce_application (void *cls, const struct GNUNET_HashCode * key, void *value
 
   block.id = my_full_id;
   c =  GNUNET_CONTAINER_multihashmap_get (applications, key);
+  GNUNET_assert(NULL != c);
   block.type = (long) GNUNET_CONTAINER_multihashmap_get (c->apps, key);
   if (0 == block.type)
   {
@@ -1770,23 +1848,9 @@ announce_id (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 static void
 data_descriptor_decrement_rc (struct MeshData *mesh_data)
 {
-  /* Make sure it's a multicast packet */
-  GNUNET_assert (NULL != mesh_data->reference_counter);
-
-  if (0 == --(*(mesh_data->reference_counter)))
+  if (0 == --(mesh_data->reference_counter))
   {
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Last copy!\n");
-    if (NULL != mesh_data->task)
-    {
-      if (GNUNET_SCHEDULER_NO_TASK != *(mesh_data->task))
-      {
-        GNUNET_SCHEDULER_cancel (*(mesh_data->task));
-        GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, " notifying client...\n");
-        GNUNET_SERVER_receive_done (mesh_data->t->owner->handle, GNUNET_OK);
-      }
-      GNUNET_free (mesh_data->task);
-    }
-    GNUNET_free (mesh_data->reference_counter);
     GNUNET_free (mesh_data->data);
     GNUNET_free (mesh_data);
   }
@@ -1842,32 +1906,6 @@ client_is_subscribed (uint16_t message_type, struct MeshClient *c)
 }
 
 
-/**
- * Allow a client to send more data after transmitting a multicast message
- * which some neighbor has not yet accepted altough a reasonable time has
- * passed.
- *
- * @param cls Closure (DataDescriptor containing the task identifier)
- * @param tc Task Context
- * 
- * FIXME reference counter cshould be just int
- */
-static void
-client_allow_send (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
-{
-  struct MeshData *mdata = cls;
-
-  if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
-    return;
-  GNUNET_assert (NULL != mdata->reference_counter);
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-              "CLIENT ALLOW SEND DESPITE %u COPIES PENDING\n",
-              *(mdata->reference_counter));
-  *(mdata->task) = GNUNET_SCHEDULER_NO_TASK;
-  GNUNET_SERVER_receive_done (mdata->t->owner->handle, GNUNET_OK);
-}
-
-
 /**
  * Check whether client wants traffic from a tunnel.
  *
@@ -2274,9 +2312,9 @@ send_core_data_raw (void *cls, size_t size, void *buf)
  * @param t Tunnel on which this message is transmitted.
  */
 static void
-send_message (const struct GNUNET_MessageHeader *message,
-              const struct GNUNET_PeerIdentity *peer,
-              struct MeshTunnel *t)
+send_prebuilt_message (const struct GNUNET_MessageHeader *message,
+                       const struct GNUNET_PeerIdentity *peer,
+                       struct MeshTunnel *t)
 {
   struct MeshTransmissionDescriptor *info;
   struct MeshPeerInfo *neighbor;
@@ -2300,8 +2338,8 @@ send_message (const struct GNUNET_MessageHeader *message,
     m->ttl = htonl (ntohl (m->ttl) - 1);
   }
   info->mesh_data->data_len = size;
-  info->mesh_data->reference_counter = GNUNET_malloc (sizeof (unsigned int));
-  *info->mesh_data->reference_counter = 1;
+  info->mesh_data->reference_counter = 1;
+  info->mesh_data->total_out = 1;
   neighbor = peer_info_get (peer);
   for (p = neighbor->path_head; NULL != p; p = p->next)
   {
@@ -2344,16 +2382,7 @@ send_message (const struct GNUNET_MessageHeader *message,
   }
   info->peer = neighbor;
   if (GNUNET_MESSAGE_TYPE_MESH_PATH_ACK == type)
-  {
-    /*
-     * TODO: in this case we only need the service to retransmit
-     * the message down the path. If we pass the real type to queue_add,
-     * queue_send will try to build the message from scratch. This can
-     * probably be done by some other way instead of deleteing the type
-     * info.
-     */
     type = 0;
-  }
   queue_add (info,
              type,
              size,
@@ -2451,12 +2480,39 @@ send_destroy_path (struct MeshTunnel *t, GNUNET_PEER_Id destination)
     {
       GNUNET_PEER_resolve (p->peers[i], &pi[i]);
     }
-    send_message (&msg->header, tree_get_first_hop (t->tree, destination), t);
+    send_prebuilt_message (&msg->header, tree_get_first_hop (t->tree, destination), t);
   }
   path_destroy (p);
 }
 
 
+/**
+ * Sends a PATH ACK message in reponse to a received PATH_CREATE directed to us.
+ *
+ * @param t Tunnel which to confirm.
+ */
+static void
+send_path_ack (struct MeshTunnel *t) 
+{
+  struct MeshTransmissionDescriptor *info;
+  struct GNUNET_PeerIdentity id;
+  GNUNET_PEER_Id peer;
+
+  peer = tree_get_predecessor (t->tree);
+  GNUNET_PEER_resolve (peer, &id);
+  info = GNUNET_malloc (sizeof (struct MeshTransmissionDescriptor));
+  info->origin = &t->id;
+  info->peer = GNUNET_CONTAINER_multihashmap_get (peers, &id.hashPubKey);
+  GNUNET_assert (NULL != info->peer);
+
+  queue_add (info,
+             GNUNET_MESSAGE_TYPE_MESH_PATH_ACK,
+             sizeof (struct GNUNET_MESH_PathACK),
+             info->peer,
+             t);
+}
+
+
 /**
  * Try to establish a new connection to this peer.
  * Use the best path for the given tunnel.
@@ -3064,7 +3120,10 @@ tunnel_delete_client (struct MeshTunnel *t, const struct MeshClient *c)
 
 
 /**
- * Iterator to free MeshTunnelChildInfo of tunnel children.
+ * @brief Iterator to destroy MeshTunnelChildInfo of tunnel children.
+ * 
+ * Destroys queue elements of all waiting transmissions and frees all memory
+ * used by the struct and its elements.
  *
  * @param cls Closure (tunnel info).
  * @param key Hash of GNUNET_PEER_Id (unused).
@@ -3077,7 +3136,22 @@ tunnel_destroy_child (void *cls,
                       const struct GNUNET_HashCode * key,
                       void *value)
 {
-  GNUNET_free (value);
+  struct MeshTunnelChildInfo *cinfo = value;
+  struct MeshTunnel *t = cls;
+  unsigned int c;
+  unsigned int i;
+
+  for (c = 0; c < cinfo->send_buffer_n; c++)
+  {
+    i = (cinfo->send_buffer_start + c) % t->fwd_queue_max;
+    if (NULL != cinfo->send_buffer[i])
+      queue_destroy (cinfo->send_buffer[i], GNUNET_YES);
+    else
+      GNUNET_break (0);
+    GNUNET_log (GNUNET_ERROR_TYPE_INFO, "%u %u\n", c, cinfo->send_buffer_n);
+  }
+  GNUNET_free_non_null (cinfo->send_buffer);
+  GNUNET_free (cinfo);
   return GNUNET_YES;
 }
 
@@ -3262,7 +3336,7 @@ tunnel_notify_connection_broken (struct MeshTunnel *t, GNUNET_PEER_Id p1,
       msg.peer1 = my_full_id;
       GNUNET_PEER_resolve (pid, &msg.peer2);
       GNUNET_PEER_resolve (tree_get_predecessor (t->tree), &neighbor);
-      send_message (&msg.header, &neighbor, t);
+      send_prebuilt_message (&msg.header, &neighbor, t);
     }
   }
   return pid;
@@ -3281,19 +3355,21 @@ tunnel_send_multicast_iterator (void *cls, GNUNET_PEER_Id neighbor_id)
   struct MeshData *mdata = cls;
   struct MeshTransmissionDescriptor *info;
   struct GNUNET_PeerIdentity neighbor;
+  struct GNUNET_MessageHeader *msg;
 
   info = GNUNET_malloc (sizeof (struct MeshTransmissionDescriptor));
 
   info->mesh_data = mdata;
-  (*(mdata->reference_counter)) ++;
+  (mdata->reference_counter) ++;
   info->destination = neighbor_id;
   GNUNET_PEER_resolve (neighbor_id, &neighbor);
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "   sending to %s...\n",
               GNUNET_i2s (&neighbor));
   info->peer = peer_info_get (&neighbor);
   GNUNET_assert (NULL != info->peer);
+  msg = (struct GNUNET_MessageHeader *) mdata->data;
   queue_add(info,
-            GNUNET_MESSAGE_TYPE_MESH_MULTICAST,
+            ntohs (msg->type),
             info->mesh_data->data_len,
             info->peer,
             mdata->t);
@@ -3306,12 +3382,10 @@ tunnel_send_multicast_iterator (void *cls, GNUNET_PEER_Id neighbor_id)
  *
  * @param t Tunnel in which to send the data.
  * @param msg Message to be sent.
- * @param internal Has the service generated this message?
  */
 static void
 tunnel_send_multicast (struct MeshTunnel *t,
-                       const struct GNUNET_MessageHeader *msg,
-                       int internal)
+                       const struct GNUNET_MessageHeader *msg)
 {
   struct MeshData *mdata;
 
@@ -3320,7 +3394,6 @@ tunnel_send_multicast (struct MeshTunnel *t,
 
   mdata = GNUNET_malloc (sizeof (struct MeshData));
   mdata->data_len = ntohs (msg->size);
-  mdata->reference_counter = GNUNET_malloc (sizeof (unsigned int));
   mdata->t = t;
   mdata->data = GNUNET_malloc (mdata->data_len);
   memcpy (mdata->data, msg, mdata->data_len);
@@ -3328,17 +3401,22 @@ tunnel_send_multicast (struct MeshTunnel *t,
   {
     struct GNUNET_MESH_Multicast *mcast;
 
+    mcast = (struct GNUNET_MESH_Multicast *) mdata->data;
     if (t->fwd_queue_n >= t->fwd_queue_max)
     {
       GNUNET_break (0);
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "  queue full!\n");
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "  queue full!\n");
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                  "  message from %s!\n",
+                  GNUNET_i2s(&mcast->oid));
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                  "  message at %s!\n",
+                  GNUNET_i2s(&my_full_id));
       GNUNET_free (mdata->data);
-      GNUNET_free (mdata->reference_counter);
       GNUNET_free (mdata);
       return;
     }
     t->fwd_queue_n++;
-    mcast = (struct GNUNET_MESH_Multicast *) mdata->data;
     mcast->ttl = htonl (ntohl (mcast->ttl) - 1);
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "  data packet, ttl: %u\n",
                 ntohl (mcast->ttl));
@@ -3347,34 +3425,20 @@ tunnel_send_multicast (struct MeshTunnel *t,
   {
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "  not a data packet, no ttl\n");
   }
-  if (NULL != t->owner &&
-      GNUNET_YES != t->owner->shutting_down &&
-      GNUNET_NO == internal)
-  {
-    mdata->task = GNUNET_malloc (sizeof (GNUNET_SCHEDULER_TaskIdentifier));
-    (*(mdata->task)) =
-        GNUNET_SCHEDULER_add_delayed (unacknowledged_wait_time, &client_allow_send,
-                                      mdata);
-    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "timeout task %u\n",
-                *(mdata->task));
-  }
 
   tree_iterate_children (t->tree, &tunnel_send_multicast_iterator, mdata);
-  if (*(mdata->reference_counter) == 0)
+  if (mdata->reference_counter == 0)
   {
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
               "  no one to send data to\n");
     GNUNET_free (mdata->data);
-    GNUNET_free (mdata->reference_counter);
-    if (NULL != mdata->task)
-    {
-      GNUNET_SCHEDULER_cancel(*(mdata->task));
-      GNUNET_free (mdata->task);
-      GNUNET_SERVER_receive_done (t->owner->handle, GNUNET_OK);
-    }
     GNUNET_free (mdata);
     t->fwd_queue_n--;
   }
+  else
+  {
+    mdata->total_out = mdata->reference_counter;
+  }
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
               " sending a multicast packet done\n");
   return;
@@ -3526,7 +3590,7 @@ tunnel_get_child_fwd_ack (void *cls,
  *
  * @param t Tunnel.
  *
- * @return Maximum PID allowed (uint32 MAX), -1 if node has no children.
+ * @return Maximum PID allowed (uint32 MAX), -1LL if node has no children.
  */
 static int64_t
 tunnel_get_children_fwd_ack (struct MeshTunnel *t)
@@ -3535,6 +3599,7 @@ tunnel_get_children_fwd_ack (struct MeshTunnel *t)
   ctx.t = t;
   ctx.max_child_ack = 0;
   ctx.nchildren = 0;
+  ctx.init = GNUNET_NO;
   tree_iterate_children (t->tree, tunnel_get_child_fwd_ack, &ctx);
 
   if (0 == ctx.nchildren)
@@ -3583,7 +3648,7 @@ tunnel_set_client_fwd_ack (struct MeshTunnel *t,
  * @param t Tunnel on which to look.
  * 
  * @return Corresponding ACK value (max uint32_t).
- *         If no clients are suscribed, -1.
+ *         If no clients are suscribed, -1LL.
  */
 static int64_t
 tunnel_get_clients_fwd_ack (struct MeshTunnel *t)
@@ -3598,9 +3663,9 @@ tunnel_get_clients_fwd_ack (struct MeshTunnel *t)
     return -1LL;
   }
 
-  for (ack = -1, i = 0; i < t->nclients; i++)
+  for (ack = -1LL, i = 0; i < t->nclients; i++)
   {
-    if (-1 == ack ||
+    if (-1LL == ack ||
         (GNUNET_YES == t->speed_min &&
          GNUNET_YES == GMC_is_pid_bigger (ack, t->clients_fc[i].fwd_ack)) ||
         (GNUNET_NO == t->speed_min &&
@@ -3628,37 +3693,41 @@ tunnel_get_clients_fwd_ack (struct MeshTunnel *t)
 static uint32_t
 tunnel_get_fwd_ack (struct MeshTunnel *t)
 {
+  uint32_t ack;
   uint32_t count;
   uint32_t buffer_free;
   int64_t child_ack;
   int64_t client_ack;
-  uint32_t ack;
 
   count = t->fwd_pid - t->skip;
   buffer_free = t->fwd_queue_max - t->fwd_queue_n;
-  ack = count + buffer_free; // Might overflow 32 bits, it's ok!
+  ack = count;
   child_ack = tunnel_get_children_fwd_ack (t);
   client_ack = tunnel_get_clients_fwd_ack (t);
-  if (-1 == child_ack)
+  if (-1LL == child_ack)
   {
     // Node has no children, child_ack AND core buffer are irrelevant.
-    GNUNET_break (-1 != client_ack); // No children AND no clients? Not good!
+    GNUNET_break (-1LL != client_ack); // No children AND no clients? Not good!
     return (uint32_t) client_ack;
   }
-
+  if (-1LL == client_ack)
+  {
+    client_ack = ack + buffer_free; // Might overflow 32 bits, it's ok!
+  }
   if (GNUNET_YES == t->speed_min)
   {
-    ack = GMC_min_pid ((uint32_t) child_ack, ack);
+    ack = GMC_min_pid ((uint32_t) child_ack, ack) + buffer_free; // Might overflow 32 bits, it's ok!;
     ack = GMC_min_pid ((uint32_t) client_ack, ack);
   }
   else
   {
-    ack = GMC_max_pid ((uint32_t) child_ack, ack);
+    ack = GMC_max_pid ((uint32_t) child_ack, ack) + buffer_free; // Might overflow 32 bits, it's ok!;
     ack = GMC_max_pid ((uint32_t) client_ack, ack);
   }
   if (GNUNET_YES == t->nobuffer && GMC_is_pid_bigger(ack, t->fwd_pid))
     ack = t->fwd_pid + 1; // Might overflow 32 bits, it's ok!
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "c %u, bf %u, ch %u, cl %u, ACK: %u\n",
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "c %u, bf %u, ch %lld, cl %lld, ACK: %u\n",
               count, buffer_free, child_ack, client_ack, ack);
   return ack;
 }
@@ -3704,7 +3773,7 @@ send_ack (struct MeshTunnel *t, struct GNUNET_PeerIdentity *peer,  uint32_t ack)
   msg.pid = htonl (ack);
   msg.tid = htonl (t->id.tid);
 
-  send_message (&msg.header, peer, t);
+  send_prebuilt_message (&msg.header, peer, t);
 }
 
 
@@ -3769,18 +3838,6 @@ tunnel_send_fwd_ack (struct MeshTunnel *t, uint16_t type)
         GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, nobuffer\n");
         return;
       }
-      if (t->fwd_queue_max > t->fwd_queue_n * 2 &&
-          GMC_is_pid_bigger(t->last_fwd_ack, t->fwd_pid))
-      {
-        GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer free\n");
-        GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                    "  t->qmax: %u, t->qn: %u\n",
-                    t->fwd_queue_max, t->fwd_queue_n);
-        GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                    "  t->pid: %u, t->ack: %u\n",
-                    t->fwd_pid, t->last_fwd_ack);
-        return;
-      }
       break;
     case GNUNET_MESSAGE_TYPE_MESH_ACK:
     case GNUNET_MESSAGE_TYPE_MESH_LOCAL_ACK:
@@ -3789,6 +3846,20 @@ tunnel_send_fwd_ack (struct MeshTunnel *t, uint16_t type)
       GNUNET_break (0);
   }
 
+  /* Check if we need no retransmit the ACK */
+  if (t->fwd_queue_max > t->fwd_queue_n * 4 &&
+      GMC_is_pid_bigger(t->last_fwd_ack, t->fwd_pid))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, buffer free\n");
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "  t->qmax: %u, t->qn: %u\n",
+                t->fwd_queue_max, t->fwd_queue_n);
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "  t->pid: %u, t->ack: %u\n",
+                t->fwd_pid, t->last_fwd_ack);
+    return;
+  }
+
   /* Ok, ACK might be necessary, what PID to ACK? */
   ack = tunnel_get_fwd_ack (t);
 
@@ -3802,6 +3873,7 @@ tunnel_send_fwd_ack (struct MeshTunnel *t, uint16_t type)
   t->last_fwd_ack = ack;
   GNUNET_PEER_resolve (tree_get_predecessor (t->tree), &id);
   send_ack (t, &id, ack);
+  debug_fwd_ack++;
 }
 
 
@@ -4016,7 +4088,7 @@ tunnel_send_destroy (struct MeshTunnel *t)
   msg.header.type = htons (GNUNET_MESSAGE_TYPE_MESH_TUNNEL_DESTROY);
   GNUNET_PEER_resolve (t->id.oid, &msg.oid);
   msg.tid = htonl (t->id.tid);
-  tunnel_send_multicast (t, &msg.header, GNUNET_NO);
+  tunnel_send_multicast (t, &msg.header);
 }
 
 
@@ -4040,6 +4112,13 @@ tunnel_cancel_queues (void *cls, GNUNET_PEER_Id neighbor_id)
     next = pq->next;
     if (pq->tunnel == t)
     {
+      if (GNUNET_MESSAGE_TYPE_MESH_MULTICAST == pq->type ||
+          GNUNET_MESSAGE_TYPE_MESH_UNICAST == pq->type ||
+          GNUNET_MESSAGE_TYPE_MESH_TO_ORIGIN == pq->type)
+      {
+        // Should have been removed on destroy children
+        GNUNET_break (0);
+      }
       queue_destroy (pq, GNUNET_YES);
     }
   }
@@ -4068,8 +4147,6 @@ tunnel_destroy (struct MeshTunnel *t)
   if (NULL == t)
     return GNUNET_OK;
 
-  tree_iterate_children (t->tree, &tunnel_cancel_queues, t);
-
   r = GNUNET_OK;
   c = t->owner;
 #if MESH_DEBUG
@@ -4087,16 +4164,21 @@ tunnel_destroy (struct MeshTunnel *t)
   GNUNET_CRYPTO_hash (&t->id, sizeof (struct MESH_TunnelID), &hash);
   if (GNUNET_YES != GNUNET_CONTAINER_multihashmap_remove (tunnels, &hash, t))
   {
+    GNUNET_break (0);
     r = GNUNET_SYSERR;
   }
 
-  GNUNET_CRYPTO_hash (&t->local_tid, sizeof (MESH_TunnelNumber), &hash);
-  if (NULL != c &&
-      GNUNET_YES !=
-      GNUNET_CONTAINER_multihashmap_remove (c->own_tunnels, &hash, t))
+  if (NULL != c)
   {
-    r = GNUNET_SYSERR;
+    GNUNET_CRYPTO_hash (&t->local_tid, sizeof (MESH_TunnelNumber), &hash);
+    if (GNUNET_YES !=
+        GNUNET_CONTAINER_multihashmap_remove (c->own_tunnels, &hash, t))
+    {
+      GNUNET_break (0);
+      r = GNUNET_SYSERR;
+    }
   }
+
   GNUNET_CRYPTO_hash (&t->local_tid_dest, sizeof (MESH_TunnelNumber), &hash);
   for (i = 0; i < t->nclients; i++)
   {
@@ -4104,6 +4186,7 @@ tunnel_destroy (struct MeshTunnel *t)
     if (GNUNET_YES !=
           GNUNET_CONTAINER_multihashmap_remove (c->incoming_tunnels, &hash, t))
     {
+      GNUNET_break (0);
       r = GNUNET_SYSERR;
     }
   }
@@ -4113,18 +4196,22 @@ tunnel_destroy (struct MeshTunnel *t)
     if (GNUNET_YES !=
           GNUNET_CONTAINER_multihashmap_remove (c->ignore_tunnels, &hash, t))
     {
+      GNUNET_break (0);
       r = GNUNET_SYSERR;
     }
   }
+
   if (t->nclients > 0)
   {
     if (GNUNET_YES !=
         GNUNET_CONTAINER_multihashmap_remove (incoming_tunnels, &hash, t))
     {
+      GNUNET_break (0);
       r = GNUNET_SYSERR;
     }
     GNUNET_free (t->clients);
   }
+
   if (NULL != t->peers)
   {
     GNUNET_CONTAINER_multihashmap_iterate (t->peers, &peer_info_delete_tunnel,
@@ -4137,6 +4224,8 @@ tunnel_destroy (struct MeshTunnel *t)
                                          t);
   GNUNET_CONTAINER_multihashmap_destroy (t->children_fc);
 
+  tree_iterate_children (t->tree, &tunnel_cancel_queues, t);
+
   tree_destroy (t->tree);
 
   if (NULL != t->regex_ctx)
@@ -4253,14 +4342,13 @@ tunnel_delete_peer (struct MeshTunnel *t, GNUNET_PEER_Id peer)
  * @param key the hash of the local tunnel id (used to access the hashmap)
  * @param value the value stored at the key (tunnel to destroy)
  *
- * @return GNUNET_OK on success
+ * @return GNUNET_OK, keep iterating.
  */
 static int
 tunnel_destroy_iterator (void *cls, const struct GNUNET_HashCode * key, void *value)
 {
   struct MeshTunnel *t = value;
   struct MeshClient *c = cls;
-  int r;
 
   send_client_tunnel_disconnect(t, c);
   if (c != t->owner)
@@ -4272,8 +4360,10 @@ tunnel_destroy_iterator (void *cls, const struct GNUNET_HashCode * key, void *va
     return GNUNET_OK;
   }
   tunnel_send_destroy(t);
-  r = tunnel_destroy (t);
-  return r;
+  t->owner = NULL;
+  t->destroy = GNUNET_YES;
+
+  return GNUNET_OK;
 }
 
 
@@ -4287,10 +4377,15 @@ static void
 tunnel_timeout (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   struct MeshTunnel *t = cls;
+  struct GNUNET_PeerIdentity id;
 
+  t->timeout_task = GNUNET_SCHEDULER_NO_TASK;
   if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
     return;
-  t->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+  GNUNET_PEER_resolve(t->id.oid, &id);
+  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+              "Tunnel %s [%X] timed out. Destroying.\n",
+              GNUNET_i2s(&id), t->id.tid);
   tunnel_destroy (t);
 }
 
@@ -4351,11 +4446,13 @@ send_core_path_create (void *cls, size_t size, void *buf)
   msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_PATH_CREATE);
   msg->tid = ntohl (t->id.tid);
 
+  opt = 0;
   if (GNUNET_YES == t->speed_min)
-    opt = MESH_TUNNEL_OPT_SPEED_MIN;
+    opt |= MESH_TUNNEL_OPT_SPEED_MIN;
   if (GNUNET_YES == t->nobuffer)
     opt |= MESH_TUNNEL_OPT_NOBUFFER;
   msg->opt = htonl(opt);
+  msg->reserved = 0;
 
   peer_ptr = (struct GNUNET_PeerIdentity *) &msg[1];
   for (i = 0; i < p->length; i++)
@@ -4477,32 +4574,72 @@ queue_destroy (struct MeshPeerQueue *queue, int clear_cls)
 {
   struct MeshTransmissionDescriptor *dd;
   struct MeshPathInfo *path_info;
+  struct MeshTunnelChildInfo *cinfo;
+  struct GNUNET_PeerIdentity id;
+  unsigned int i;
+  unsigned int max;
 
   if (GNUNET_YES == clear_cls)
   {
     switch (queue->type)
     {
-    case GNUNET_MESSAGE_TYPE_MESH_UNICAST:
-    case GNUNET_MESSAGE_TYPE_MESH_MULTICAST:
-    case GNUNET_MESSAGE_TYPE_MESH_TO_ORIGIN:
-        GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "   type payload\n");
+      case GNUNET_MESSAGE_TYPE_MESH_TUNNEL_DESTROY:
+        GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "   cancelling TUNNEL_DESTROY\n");
+        /* fall through */
+      case GNUNET_MESSAGE_TYPE_MESH_UNICAST:
+      case GNUNET_MESSAGE_TYPE_MESH_MULTICAST:
+      case GNUNET_MESSAGE_TYPE_MESH_TO_ORIGIN:
+        GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                    "   type prebuilt (payload, tunnel destroy)\n");
         dd = queue->cls;
         data_descriptor_decrement_rc (dd->mesh_data);
         break;
-    case GNUNET_MESSAGE_TYPE_MESH_PATH_CREATE:
+      case GNUNET_MESSAGE_TYPE_MESH_PATH_CREATE:
         GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "   type create path\n");
         path_info = queue->cls;
         path_destroy (path_info->path);
         break;
-    default:
+      default:
         GNUNET_break (0);
-        GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "   type unknown!\n");
+        GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                    "   type %s unknown!\n",
+                    GNUNET_MESH_DEBUG_M2S(queue->type));
     }
     GNUNET_free_non_null (queue->cls);
   }
   GNUNET_CONTAINER_DLL_remove (queue->peer->queue_head,
                                queue->peer->queue_tail,
                                queue);
+
+  /* Delete from child_fc in the appropiate tunnel */
+  max = queue->tunnel->fwd_queue_max;
+  GNUNET_PEER_resolve (queue->peer->id, &id);
+  cinfo = tunnel_get_neighbor_fc (queue->tunnel, &id);
+  for (i = 0; i < cinfo->send_buffer_n; i++)
+  {
+    unsigned int i2;
+    i2 = (cinfo->send_buffer_start + i) % max;
+    if (cinfo->send_buffer[i2] == queue)
+    {
+      /* Found corresponding entry in the send_buffer. Move all others back. */
+      unsigned int j;
+      unsigned int j2;
+      unsigned int j3;
+
+      for (j = i, j2 = 0, j3 = 0; j < cinfo->send_buffer_n - 1; j++)
+      {
+        j2 = (cinfo->send_buffer_start + j) % max;
+        j3 = (cinfo->send_buffer_start + j + 1) % max;
+        cinfo->send_buffer[j2] = cinfo->send_buffer[j3];
+      }
+
+      cinfo->send_buffer[j3] = NULL;
+
+      cinfo->send_buffer_n--;
+    }
+  }
+  //queue->
+
   GNUNET_free (queue);
 }
 
@@ -4608,40 +4745,40 @@ queue_send (void *cls, size_t size, void *buf)
     struct GNUNET_MessageHeader *msg;
     struct MeshPeerQueue *queue;
     struct MeshTunnel *t;
+    struct MeshTunnelChildInfo *cinfo;
+    struct GNUNET_PeerIdentity dst_id;
     size_t data_size;
 
     peer->core_transmit = NULL;
-    
+
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "********* Queue send\n");
-    queue = queue_get_next(peer);
+    queue = queue_get_next (peer);
 
-    /* Queue has no internal mesh traffic not sendable payload */
+    /* Queue has no internal mesh traffic nor sendable payload */
     if (NULL == queue)
     {
       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*********   not ready, return\n");
       if (NULL == peer->queue_head)
-        GNUNET_break(0); // Should've been canceled
+        GNUNET_break (0); // Should've been canceled
       return 0;
     }
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*********   not empty\n");
 
+    GNUNET_PEER_resolve (peer->id, &dst_id);
     /* Check if buffer size is enough for the message */
     if (queue->size > size)
     {
-        struct GNUNET_PeerIdentity id;
-
         GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
                     "*********   not enough room, reissue\n");
-        GNUNET_PEER_resolve (peer->id, &id);
         peer->core_transmit =
-            GNUNET_CORE_notify_transmit_ready(core_handle,
-                                              0,
-                                              0,
-                                              GNUNET_TIME_UNIT_FOREVER_REL,
-                                              &id,
-                                              queue->size,
-                                              &queue_send,
-                                              peer);
+            GNUNET_CORE_notify_transmit_ready (core_handle,
+                                               0,
+                                               0,
+                                               GNUNET_TIME_UNIT_FOREVER_REL,
+                                               &dst_id,
+                                               queue->size,
+                                               &queue_send,
+                                               peer);
         return 0;
     }
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*********   size ok\n");
@@ -4681,7 +4818,7 @@ queue_send (void *cls, size_t size, void *buf)
             tunnel_send_fwd_ack (t, GNUNET_MESSAGE_TYPE_MESH_UNICAST);
             break;
           case GNUNET_MESSAGE_TYPE_MESH_TO_ORIGIN:
-            tunnel_send_bck_ack(t, GNUNET_MESSAGE_TYPE_MESH_TO_ORIGIN);
+            tunnel_send_bck_ack (t, GNUNET_MESSAGE_TYPE_MESH_TO_ORIGIN);
             break;
           default:
               break;
@@ -4689,18 +4826,34 @@ queue_send (void *cls, size_t size, void *buf)
         break;
       case GNUNET_MESSAGE_TYPE_MESH_MULTICAST:
         GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*********   multicast\n");
+        {
+          struct MeshTransmissionDescriptor *info = queue->cls;
+
+          if ((1 == info->mesh_data->reference_counter
+              && GNUNET_YES == t->speed_min)
+              ||
+              (info->mesh_data->total_out == info->mesh_data->reference_counter
+              && GNUNET_NO == t->speed_min))
+          {
+            GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                        "*********   considered sent\n");
+            t->fwd_queue_n--;
+          }
+        }
         data_size = send_core_data_multicast(queue->cls, size, buf);
-        // FIXME fc substract when? depending on the tunnel conf.
-        // t->fwd_queue_n--;
         tunnel_send_fwd_ack (t, GNUNET_MESSAGE_TYPE_MESH_MULTICAST);
         break;
       case GNUNET_MESSAGE_TYPE_MESH_PATH_CREATE:
         GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*********   path create\n");
-        data_size = send_core_path_create(queue->cls, size, buf);
+        data_size = send_core_path_create (queue->cls, size, buf);
         break;
       case GNUNET_MESSAGE_TYPE_MESH_PATH_ACK:
         GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*********   path ack\n");
-        data_size = send_core_path_ack(queue->cls, size, buf);
+        data_size = send_core_path_ack (queue->cls, size, buf);
+        break;
+      case GNUNET_MESSAGE_TYPE_MESH_PATH_KEEPALIVE:
+        GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*********   path keepalive\n");
+        data_size = send_core_data_multicast (queue->cls, size, buf);
         break;
       default:
         GNUNET_break (0);
@@ -4709,6 +4862,36 @@ queue_send (void *cls, size_t size, void *buf)
                     queue->type);
         data_size = 0;
     }
+    switch (queue->type)
+    {
+      case GNUNET_MESSAGE_TYPE_MESH_UNICAST:
+      case GNUNET_MESSAGE_TYPE_MESH_TO_ORIGIN:
+      case GNUNET_MESSAGE_TYPE_MESH_MULTICAST:
+        cinfo = tunnel_get_neighbor_fc (t, &dst_id);
+        if (cinfo->send_buffer[cinfo->send_buffer_start] != queue)
+        {
+          GNUNET_break (0);
+          GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                      "at pos %u (%p) != %p\n",
+                      cinfo->send_buffer_start,
+                      cinfo->send_buffer[cinfo->send_buffer_start],
+                      queue);
+        }
+        if (cinfo->send_buffer_n > 0)
+        {
+          cinfo->send_buffer[cinfo->send_buffer_start] = NULL;
+          cinfo->send_buffer_n--;
+          cinfo->send_buffer_start++;
+          cinfo->send_buffer_start %= t->fwd_queue_max;
+        }
+        else
+        {
+          GNUNET_break (0);
+        }
+        break;
+      default:
+        break;
+    }
 
     /* Free queue, but cls was freed by send_core_* */
     queue_destroy (queue, GNUNET_NO);
@@ -4720,7 +4903,8 @@ queue_send (void *cls, size_t size, void *buf)
     }
 
     /* If more data in queue, send next */
-    if (NULL != peer->queue_head)
+    queue = queue_get_next(peer);
+    if (NULL != queue)
     {
         struct GNUNET_PeerIdentity id;
 
@@ -4732,19 +4916,34 @@ queue_send (void *cls, size_t size, void *buf)
                                               0,
                                               GNUNET_TIME_UNIT_FOREVER_REL,
                                               &id,
-                                              peer->queue_head->size,
+                                              queue->size,
                                               &queue_send,
                                               peer);
     }
+    else
+    {
+      if (NULL != peer->queue_head)
+        GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                    "*********   %s stalled\n",
+                    GNUNET_i2s(&my_full_id));
+    }
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "*********   return %d\n", data_size);
     return data_size;
 }
 
 
 /**
- * Queue and pass message to core when possible.
+ * @brief Queue and pass message to core when possible.
+ * 
+ * If type is payload (UNICAST, TO_ORIGIN, MULTICAST) checks for queue status
+ * and accounts for it. In case the queue is full, the message is dropped and
+ * a break issued.
+ * 
+ * Otherwise, message is treated as internal and allowed to go regardless of 
+ * queue status.
  *
- * @param cls Closure (type dependant).
+ * @param cls Closure (@c type dependant). It will be used by queue_send to
+ *            build the message to be sent if not already prebuilt.
  * @param type Type of the message, 0 for a raw message.
  * @param size Size of the message.
  * @param dst Neighbor to send message to.
@@ -4797,14 +4996,14 @@ queue_add (void *cls, uint16_t type, size_t size,
   if (NULL == dst->core_transmit)
   {
       dst->core_transmit =
-          GNUNET_CORE_notify_transmit_ready(core_handle,
-                                            0,
-                                            0,
-                                            GNUNET_TIME_UNIT_FOREVER_REL,
-                                            &id,
-                                            size,
-                                            &queue_send,
-                                            dst);
+          GNUNET_CORE_notify_transmit_ready (core_handle,
+                                             0,
+                                             0,
+                                             GNUNET_TIME_UNIT_FOREVER_REL,
+                                             &id,
+                                             size,
+                                             &queue_send,
+                                             dst);
   }
   if (NULL == n) // Is this internal mesh traffic?
     return;
@@ -4814,12 +5013,16 @@ queue_add (void *cls, uint16_t type, size_t size,
   i = (cinfo->send_buffer_start + cinfo->send_buffer_n) % t->fwd_queue_max;
   if (NULL != cinfo->send_buffer[i])
   {
-    queue_destroy(cinfo->send_buffer[i], GNUNET_YES);
-    GNUNET_break (cinfo->send_buffer_n > 0);
-    cinfo->send_buffer_n--;
+    GNUNET_break (cinfo->send_buffer_n == t->fwd_queue_max); // aka i == start
+    queue_destroy (cinfo->send_buffer[cinfo->send_buffer_start], GNUNET_YES);
+    cinfo->send_buffer_start++;
+    cinfo->send_buffer_start %= t->fwd_queue_max;
+  }
+  else
+  {
+    cinfo->send_buffer_n++;
   }
   cinfo->send_buffer[i] = queue;
-  cinfo->send_buffer_n++;
   if (cinfo->send_buffer_n > t->fwd_queue_max)
   {
     GNUNET_break (0);
@@ -4909,6 +5112,9 @@ handle_mesh_path_create (void *cls, const struct GNUNET_PeerIdentity *peer,
                    GNUNET_YES : GNUNET_NO;
     t->nobuffer = (0 != (opt & MESH_TUNNEL_OPT_NOBUFFER)) ?
                   GNUNET_YES : GNUNET_NO;
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "  speed_min: %d, nobuffer:%d\n",
+                t->speed_min, t->nobuffer);
 
     if (GNUNET_YES == t->nobuffer)
     {
@@ -4982,13 +5188,11 @@ handle_mesh_path_create (void *cls, const struct GNUNET_PeerIdentity *peer,
   if (own_pos == size - 1)
   {
     /* It is for us! Send ack. */
-    struct MeshTransmissionDescriptor *info;
-
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "  It's for us!\n");
     peer_info_add_path_to_origin (orig_peer_info, path, GNUNET_NO);
     if (NULL == t->peers)
     {
-      /* New tunnel! Notify clients on data. */
+      /* New tunnel! Notify clients on first payload message. */
       t->peers = GNUNET_CONTAINER_multihashmap_create (4);
     }
     GNUNET_break (GNUNET_SYSERR !=
@@ -4997,15 +5201,7 @@ handle_mesh_path_create (void *cls, const struct GNUNET_PeerIdentity *peer,
                                                      peer_info_get
                                                      (&my_full_id),
                                                      GNUNET_CONTAINER_MULTIHASHMAPOPTION_REPLACE));
-    info = GNUNET_malloc (sizeof (struct MeshTransmissionDescriptor));
-    info->origin = &t->id;
-    info->peer = GNUNET_CONTAINER_multihashmap_get (peers, &peer->hashPubKey);
-    GNUNET_assert (NULL != info->peer);
-    queue_add(info,
-              GNUNET_MESSAGE_TYPE_MESH_PATH_ACK,
-              sizeof (struct GNUNET_MESH_PathACK),
-              info->peer,
-              t);
+    send_path_ack (t);
   }
   else
   {
@@ -5097,7 +5293,7 @@ handle_mesh_path_destroy (void *cls, const struct GNUNET_PeerIdentity *peer,
   }
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "  Own position: %u\n", own_pos);
   if (own_pos < path->length - 1)
-    send_message (message, &pi[own_pos + 1], t);
+    send_prebuilt_message (message, &pi[own_pos + 1], t);
   else
     send_client_tunnel_disconnect(t, NULL);
 
@@ -5315,7 +5511,7 @@ handle_mesh_data_unicast (void *cls, const struct GNUNET_PeerIdentity *peer,
     GNUNET_break_op (0);
     return GNUNET_OK;
   }
-  send_message (message, neighbor, t);
+  send_prebuilt_message (message, neighbor, t);
   GNUNET_STATISTICS_update (stats, "# unicast forwarded", 1, GNUNET_NO);
   return GNUNET_OK;
 }
@@ -5400,7 +5596,7 @@ handle_mesh_data_multicast (void *cls, const struct GNUNET_PeerIdentity *peer,
     return GNUNET_OK;
   }
   GNUNET_STATISTICS_update (stats, "# multicast forwarded", 1, GNUNET_NO);
-  tunnel_send_multicast (t, message, GNUNET_NO);
+  tunnel_send_multicast (t, message);
   return GNUNET_OK;
 }
 
@@ -5480,7 +5676,7 @@ handle_mesh_data_to_orig (void *cls, const struct GNUNET_PeerIdentity *peer,
     return GNUNET_OK;
   }
   GNUNET_PEER_resolve (tree_get_predecessor (t->tree), &id);
-  send_message (message, &id, t);
+  send_prebuilt_message (message, &id, t);
   GNUNET_STATISTICS_update (stats, "# to origin forwarded", 1, GNUNET_NO);
 
   return GNUNET_OK;
@@ -5529,6 +5725,7 @@ handle_mesh_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
   {
     struct MeshTunnelChildInfo *cinfo;
 
+    debug_bck_ack++;
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "  FWD ACK\n");
     cinfo = tunnel_get_neighbor_fc (t, peer);
     cinfo->fwd_ack = ack;
@@ -5643,11 +5840,56 @@ handle_mesh_path_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
     GNUNET_break (0);
     return GNUNET_OK;
   }
-  send_message (message, &id, t);
+  send_prebuilt_message (message, &id, t);
   return GNUNET_OK;
 }
 
 
+/**
+ * Core handler for mesh keepalives.
+ *
+ * @param cls closure
+ * @param message message
+ * @param peer peer identity this notification is about
+ * @param atsi performance data
+ * @param atsi_count number of records in 'atsi'
+ * @return GNUNET_OK to keep the connection open,
+ *         GNUNET_SYSERR to close it (signal serious error)
+ *
+ * TODO: Check who we got this from, to validate route.
+ */
+static int
+handle_mesh_keepalive (void *cls, const struct GNUNET_PeerIdentity *peer,
+                       const struct GNUNET_MessageHeader *message,
+                       const struct GNUNET_ATS_Information *atsi,
+                       unsigned int atsi_count)
+{
+  struct GNUNET_MESH_TunnelKeepAlive *msg;
+  struct MeshTunnel *t;
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "got a keepalive packet from %s\n",
+              GNUNET_i2s (peer));
+
+  msg = (struct GNUNET_MESH_TunnelKeepAlive *) message;
+  t = tunnel_get (&msg->oid, ntohl (msg->tid));
+
+  if (NULL == t)
+  {
+    /* TODO notify that we dont know that tunnel */
+    GNUNET_STATISTICS_update (stats, "# keepalive on unknown tunnel", 1, GNUNET_NO);
+    GNUNET_break_op (0);
+    return GNUNET_OK;
+  }
+
+  tunnel_reset_timeout (t);
+
+  GNUNET_STATISTICS_update (stats, "# keepalives forwarded", 1, GNUNET_NO);
+  tunnel_send_multicast (t, message);
+  return GNUNET_OK;
+  }
+
+
+
 /**
  * Functions to handle messages from core
  */
@@ -5660,6 +5902,8 @@ static struct GNUNET_CORE_MessageHandler core_handlers[] = {
    sizeof (struct GNUNET_MESH_TunnelDestroy)},
   {&handle_mesh_data_unicast, GNUNET_MESSAGE_TYPE_MESH_UNICAST, 0},
   {&handle_mesh_data_multicast, GNUNET_MESSAGE_TYPE_MESH_MULTICAST, 0},
+  {&handle_mesh_keepalive, GNUNET_MESSAGE_TYPE_MESH_PATH_KEEPALIVE,
+    sizeof (struct GNUNET_MESH_TunnelKeepAlive)},
   {&handle_mesh_data_to_orig, GNUNET_MESSAGE_TYPE_MESH_TO_ORIGIN, 0},
   {&handle_mesh_ack, GNUNET_MESSAGE_TYPE_MESH_ACK,
     sizeof (struct GNUNET_MESH_ACK)},
@@ -5737,46 +5981,34 @@ notify_client_connection_failure (void *cls, size_t size, void *buf)
  *
  * @param cls Closure (tunnel for which to send the keepalive).
  * @param tc Notification context.
- *
- * TODO: implement explicit multicast keepalive?
  */
 static void
 path_refresh (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   struct MeshTunnel *t = cls;
-  struct GNUNET_MessageHeader *payload;
-  struct GNUNET_MESH_Multicast *msg;
-  size_t size =
-      sizeof (struct GNUNET_MESH_Multicast) +
-      sizeof (struct GNUNET_MessageHeader);
+  struct GNUNET_MESH_TunnelKeepAlive *msg;
+  size_t size = sizeof (struct GNUNET_MESH_TunnelKeepAlive);
   char cbuf[size];
 
+  t->path_refresh_task = GNUNET_SCHEDULER_NO_TASK;
   if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
   {
     return;
   }
-  t->path_refresh_task = GNUNET_SCHEDULER_NO_TASK;
 
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
               "sending keepalive for tunnel %d\n", t->id.tid);
 
-  msg = (struct GNUNET_MESH_Multicast *) cbuf;
+  msg = (struct GNUNET_MESH_TunnelKeepAlive *) cbuf;
   msg->header.size = htons (size);
-  msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_MULTICAST);
-  // FIXME: change type to != MULTICAST
+  msg->header.type = htons (GNUNET_MESSAGE_TYPE_MESH_PATH_KEEPALIVE);
   msg->oid = my_full_id;
   msg->tid = htonl (t->id.tid);
-  msg->ttl = htonl (default_ttl);
-  msg->pid = htonl (t->fwd_pid + 1);
-  t->fwd_pid++;
-  payload = (struct GNUNET_MessageHeader *) &msg[1];
-  payload->size = htons (sizeof (struct GNUNET_MessageHeader));
-  payload->type = htons (GNUNET_MESSAGE_TYPE_MESH_PATH_KEEPALIVE);
-  tunnel_send_multicast (t, &msg->header, GNUNET_YES);
+  tunnel_send_multicast (t, &msg->header);
 
   t->path_refresh_task =
       GNUNET_SCHEDULER_add_delayed (refresh_path_time, &path_refresh, t);
-  return;
+  tunnel_reset_timeout(t);
 }
 
 
@@ -5969,7 +6201,8 @@ dht_get_string_handler (void *cls, struct GNUNET_TIME_Absolute exp,
                         const struct GNUNET_PeerIdentity *get_path,
                         unsigned int get_path_length,
                         const struct GNUNET_PeerIdentity *put_path,
-                        unsigned int put_path_length, enum GNUNET_BLOCK_Type type,
+                        unsigned int put_path_length,
+                        enum GNUNET_BLOCK_Type type,
                         size_t size, const void *data)
 {
   const struct MeshRegexBlock *block = data;
@@ -6014,9 +6247,9 @@ dht_get_string_handler (void *cls, struct GNUNET_TIME_Absolute exp,
     }
     return;
   }
-  GNUNET_break (GNUNET_OK ==
-                GNUNET_MESH_regex_block_iterate (block, size,
-                                                 &regex_edge_iterator, ctx));
+
+  regex_next_edge (block, size, ctx);
+
   return;
 }
 
@@ -7324,7 +7557,7 @@ handle_local_multicast (void *cls, struct GNUNET_SERVER_Client *client,
     handle_mesh_data_multicast (client, &my_full_id, &copy->header, NULL, 0);
   }
 
-  /* receive done gets called when last copy is sent to a neighbor */
+  GNUNET_SERVER_receive_done (t->owner->handle, GNUNET_OK);
   return;
 }
 
@@ -7539,13 +7772,15 @@ core_disconnect (void *cls, const struct GNUNET_PeerIdentity *peer)
   while (NULL != q)
   {
       n = q->next;
-      if (q->peer == pi)
-      {
-        /* try to reroute this traffic instead */
-        queue_destroy(q, GNUNET_YES);
-      }
+      /* TODO try to reroute this traffic instead */
+      queue_destroy(q, GNUNET_YES);
       q = n;
   }
+  if (NULL != pi->core_transmit)
+  {
+    GNUNET_CORE_notify_transmit_ready_cancel(pi->core_transmit);
+    pi->core_transmit = NULL;
+  }
   peer_info_remove_path (pi, pi->id, myid);
   if (myid == pi->id)
   {
@@ -7608,6 +7843,7 @@ shutdown_peer (void *cls, const struct GNUNET_HashCode * key, void *value)
   return GNUNET_YES;
 }
 
+
 /**
  * Task run during shutdown.
  *
@@ -7624,6 +7860,11 @@ shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
     GNUNET_CORE_disconnect (core_handle);
     core_handle = NULL;
   }
+ if (NULL != keygen)
+  {
+    GNUNET_CRYPTO_rsa_key_create_stop (keygen);
+    keygen = NULL;
+  }
   GNUNET_CONTAINER_multihashmap_iterate (tunnels, &shutdown_tunnel, NULL);
   GNUNET_CONTAINER_multihashmap_iterate (peers, &shutdown_peer, NULL);
   if (dht_handle != NULL)
@@ -7644,6 +7885,76 @@ shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "shut down\n");
 }
 
+
+/**
+ * Callback for hostkey read/generation
+ *
+ * @param cls NULL
+ * @param pk the private key
+ * @param emsg error message
+ */
+static void
+key_generation_cb (void *cls,
+                   struct GNUNET_CRYPTO_RsaPrivateKey *pk,
+                   const char *emsg)
+{
+  struct MeshPeerInfo *peer;
+  struct MeshPeerPath *p;
+
+  keygen = NULL;  
+  if (NULL == pk)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _("Mesh service could not access hostkey.  Exiting.\n"));
+    GNUNET_SCHEDULER_shutdown ();
+    return;
+  }
+  my_private_key = pk;
+  GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &my_public_key);
+  GNUNET_CRYPTO_hash (&my_public_key, sizeof (my_public_key),
+                      &my_full_id.hashPubKey);
+  myid = GNUNET_PEER_intern (&my_full_id);
+  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+              "Mesh for peer [%s] starting\n",
+              GNUNET_i2s(&my_full_id));
+
+//   transport_handle = GNUNET_TRANSPORT_connect(c,
+//                                               &my_full_id,
+//                                               NULL,
+//                                               NULL,
+//                                               NULL,
+//                                               NULL);
+
+
+
+  next_tid = 0;
+  next_local_tid = GNUNET_MESH_LOCAL_TUNNEL_ID_SERV;
+
+
+  GNUNET_SERVER_add_handlers (server_handle, client_handlers);
+  nc = GNUNET_SERVER_notification_context_create (server_handle, 1);
+  GNUNET_SERVER_disconnect_notify (server_handle,
+                                   &handle_local_client_disconnect, NULL);
+
+
+  clients = NULL;
+  clients_tail = NULL;
+  next_client_id = 0;
+
+  announce_applications_task = GNUNET_SCHEDULER_NO_TASK;
+  announce_id_task = GNUNET_SCHEDULER_add_now (&announce_id, cls);
+
+  /* Create a peer_info for the local peer */
+  peer = peer_info_get (&my_full_id);
+  p = path_new (1);
+  p->peers[0] = myid;
+  GNUNET_PEER_change_rc (myid, 1);
+  peer_info_add_path (peer, p, GNUNET_YES);
+  GNUNET_SERVER_resume (server_handle);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Mesh service running\n");
+}
+
+
 /**
  * Process mesh requests.
  *
@@ -7655,8 +7966,6 @@ static void
 run (void *cls, struct GNUNET_SERVER_Handle *server,
      const struct GNUNET_CONFIGURATION_Handle *c)
 {
-  struct MeshPeerInfo *peer;
-  struct MeshPeerPath *p;
   char *keyfile;
 
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "starting to run\n");
@@ -7797,76 +8106,28 @@ run (void *cls, struct GNUNET_SERVER_Handle *server,
     dht_replication_level = 10;
   }
 
-  
-  my_private_key = GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
-  GNUNET_free (keyfile);
-  if (my_private_key == NULL)
-  {
-    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                _("Mesh service could not access hostkey.  Exiting.\n"));
-    GNUNET_SCHEDULER_shutdown ();
-    return;
-  }
-  GNUNET_CRYPTO_rsa_key_get_public (my_private_key, &my_public_key);
-  GNUNET_CRYPTO_hash (&my_public_key, sizeof (my_public_key),
-                      &my_full_id.hashPubKey);
-  myid = GNUNET_PEER_intern (&my_full_id);
-  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-              "Mesh for peer [%s] starting\n",
-              GNUNET_i2s(&my_full_id));
-
-//   transport_handle = GNUNET_TRANSPORT_connect(c,
-//                                               &my_full_id,
-//                                               NULL,
-//                                               NULL,
-//                                               NULL,
-//                                               NULL);
-
-  dht_handle = GNUNET_DHT_connect (c, 64);
-  if (dht_handle == NULL)
-  {
-    GNUNET_break (0);
-  }
-
-  stats = GNUNET_STATISTICS_create ("mesh", c);
-
-
-  next_tid = 0;
-  next_local_tid = GNUNET_MESH_LOCAL_TUNNEL_ID_SERV;
-
   tunnels = GNUNET_CONTAINER_multihashmap_create (32);
   incoming_tunnels = GNUNET_CONTAINER_multihashmap_create (32);
   peers = GNUNET_CONTAINER_multihashmap_create (32);
   applications = GNUNET_CONTAINER_multihashmap_create (32);
   types = GNUNET_CONTAINER_multihashmap_create (32);
 
-  GNUNET_SERVER_add_handlers (server_handle, client_handlers);
-  nc = GNUNET_SERVER_notification_context_create (server_handle, 1);
-  GNUNET_SERVER_disconnect_notify (server_handle,
-                                   &handle_local_client_disconnect, NULL);
-
-
-  clients = NULL;
-  clients_tail = NULL;
-  next_client_id = 0;
-
-  announce_applications_task = GNUNET_SCHEDULER_NO_TASK;
-  announce_id_task = GNUNET_SCHEDULER_add_now (&announce_id, cls);
-
-  /* Create a peer_info for the local peer */
-  peer = peer_info_get (&my_full_id);
-  p = path_new (1);
-  p->peers[0] = myid;
-  GNUNET_PEER_change_rc (myid, 1);
-  peer_info_add_path (peer, p, GNUNET_YES);
+  dht_handle = GNUNET_DHT_connect (c, 64);
+  if (NULL == dht_handle)
+  {
+    GNUNET_break (0);
+  }
+  stats = GNUNET_STATISTICS_create ("mesh", c);
 
+  GNUNET_SERVER_suspend (server_handle);
   /* Scheduled the task to clean up when shutdown is called */
   GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &shutdown_task,
                                 NULL);
-
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "end of run()\n");
+  keygen = GNUNET_CRYPTO_rsa_key_create_start (keyfile, &key_generation_cb, NULL);
+  GNUNET_free (keyfile);
 }
 
+
 /**
  * The main function for the mesh service.
  *
@@ -7888,5 +8149,9 @@ main (int argc, char *const *argv)
 
   INTERVAL_SHOW;
 
+  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+              "Mesh for peer [%s] FWD ACKs %u, BCK ACKs %u\n",
+              GNUNET_i2s(&my_full_id), debug_fwd_ack, debug_bck_ack);
+
   return ret;
 }