retry faster
[oweals/gnunet.git] / src / topology / gnunet-daemon-topology.c
index b466dfbbe3e3b705f77f0ed66c48a30ea65f894a..08b1ba1c3c0effb852fa29cbd34b8880afc645ca 100644 (file)
@@ -4,7 +4,7 @@
 
      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 2, or (at your
+     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
@@ -26,6 +26,7 @@
 
 #include <stdlib.h>
 #include "platform.h"
+#include "gnunet_constants.h"
 #include "gnunet_core_service.h"
 #include "gnunet_protocols.h"
 #include "gnunet_peerinfo_service.h"
 #include "gnunet_util_lib.h"
 
 
-#define DEBUG_TOPOLOGY GNUNET_NO
+#define DEBUG_TOPOLOGY GNUNET_YES
 
 /**
  * For how long do we blacklist a peer after a failed connection
  * attempt?
  */
-#define BLACKLIST_AFTER_ATTEMPT GNUNET_TIME_UNIT_HOURS
+#define GREYLIST_AFTER_ATTEMPT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 15)
 
 /**
  * For how long do we blacklist a friend after a failed connection
  * attempt?
  */
-#define BLACKLIST_AFTER_ATTEMPT_FRIEND GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 15)
+#define GREYLIST_AFTER_ATTEMPT_FRIEND GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 2)
+
+/**
+ * For how long do we blacklist anyone under any cirumstances after a failed connection
+ * attempt?
+ */
+#define GREYLIST_AFTER_ATTEMPT_MIN GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 15)
+
+/**
+ * For how long do we blacklist anyone under any cirumstances after a failed connection
+ * attempt?
+ */
+#define GREYLIST_AFTER_ATTEMPT_MAX GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 1)
 
 /**
  * How often do we at most advertise any HELLO to a peer?
 
 
 /**
- * List of neighbours, friends and blacklisted peers.
+ * Record for neighbours, friends and blacklisted peers.
  */
-struct PeerList
+struct Peer
 {
-
   /**
-   * This is a linked list.
+   * Which peer is this entry about?
    */
-  struct PeerList *next;
+  struct GNUNET_PeerIdentity pid;
 
   /**
    * Our handle for the request to transmit HELLOs to this peer; NULL
@@ -93,32 +105,11 @@ struct PeerList
    */
   struct GNUNET_CONTAINER_BloomFilter *filter;
 
-  /**
-   * Our request handle for *whitelisting* this peer (NULL if
-   * no whitelisting request is pending).
-   */
-  struct GNUNET_TRANSPORT_BlacklistRequest *wh;
-
-  /**
-   * Is this peer listed here because he is a friend?
-   */
-  int is_friend;
-
-  /**
-   * Are we connected to this peer right now?
-   */
-  int is_connected;
-
-  /**
-   * Are we currently blocking this peer (via blacklist)?
-   */
-  int is_blocked;
-
   /**
    * Until what time should we not try to connect again
    * to this peer?
    */
-  struct GNUNET_TIME_Absolute blacklisted_until;
+  struct GNUNET_TIME_Absolute greylisted_until;
 
   /**
    * Next time we are allowed to transmit a HELLO to this peer?
@@ -137,37 +128,24 @@ struct PeerList
   GNUNET_SCHEDULER_TaskIdentifier hello_delay_task;
 
   /**
-   * ID of the peer.
+   * ID of task we use to clear peers from the greylist.
    */
-  struct GNUNET_PeerIdentity id;
+  GNUNET_SCHEDULER_TaskIdentifier greylist_clean_task;
 
-};
-
-
-/**
- * Entry in linked list of active 'disconnect' requests that we have issued.
- */
-struct DisconnectList
-{
   /**
-   * This is a doubly-linked list.
+   * How often have we tried so far?
    */
-  struct DisconnectList *next;
+  unsigned int connect_attempts;
 
   /**
-   * This is a doubly-linked list.
-   */
-  struct DisconnectList *prev;
-  
-  /**
-   * Our request handle.
+   * Is this peer listed here because he is a friend?
    */
-  struct GNUNET_TRANSPORT_BlacklistRequest *rh;
-  
+  int is_friend;
+
   /**
-   * Peer we tried to disconnect.
+   * Are we connected to this peer right now?
    */
-  struct GNUNET_PeerIdentity peer;
+  int is_connected;
 
 };
 
@@ -178,11 +156,6 @@ struct DisconnectList
  */
 static struct GNUNET_PEERINFO_NotifyContext *peerinfo_notify;
 
-/**
- * Our scheduler.
- */
-static struct GNUNET_SCHEDULER_Handle *sched;
-
 /**
  * Our configuration.
  */
@@ -204,16 +177,22 @@ static struct GNUNET_TRANSPORT_Handle *transport;
 static struct GNUNET_PeerIdentity my_identity;
 
 /**
- * Linked list of all of our friends, all of our current neighbours
- * and all peers for which we have HELLOs.  So pretty much everyone.
+ * All of our friends, all of our current neighbours and all peers for
+ * which we have HELLOs.  So pretty much everyone.  Maps peer identities
+ * to 'struct Peer *' values.
  */
-static struct PeerList *peers;
+static struct GNUNET_CONTAINER_MultiHashMap *peers;
 
 /**
  * Handle for reporting statistics.
  */
 static struct GNUNET_STATISTICS_Handle *stats;
 
+/**
+ * Blacklist (NULL if we have none).
+ */
+static struct GNUNET_TRANSPORT_Blacklist *blacklist;
+
 /**
  * Flag to disallow non-friend connections (pure F2F mode).
  */
@@ -245,220 +224,236 @@ static unsigned int friend_count;
  */
 static int autoconnect;
 
-/**
- * Head of doubly-linked list of active 'disconnect' requests that we have issued.
- */
-static struct DisconnectList *disconnect_head;
-
-/**
- * Head of doubly-linked list of active 'disconnect' requests that we have issued.
- */
-static struct DisconnectList *disconnect_tail;
-
 
 /**
- * Function called once our request to 'disconnect' a peer
- * has completed.
+ * Function that decides if a connection is acceptable or not.  
+ * If we have a blacklist, only friends are allowed, so the check
+ * is rather simple.
  *
- * @param cls our 'struct DisconnectList'
- * @param tc unused
+ * @param cls closure
+ * @param pid peer to approve or disapproave
+ * @return GNUNET_OK if the connection is allowed
  */
-static void
-disconnect_done (void *cls,
-                const struct GNUNET_SCHEDULER_TaskContext *tc)
+static int
+blacklist_check (void *cls,
+                const struct GNUNET_PeerIdentity *pid)
 {
-  struct DisconnectList *dl = cls;
+  struct Peer *pos;
 
+  pos = GNUNET_CONTAINER_multihashmap_get (peers, &pid->hashPubKey);
+  if ( (pos != NULL) &&
+       (pos->is_friend == GNUNET_YES) )
+    return GNUNET_OK;
   GNUNET_STATISTICS_update (stats,
                            gettext_noop ("# peers blacklisted"),
                            1,
                            GNUNET_NO);
-  GNUNET_CONTAINER_DLL_remove (disconnect_head,
-                              disconnect_tail,
-                              dl);
-  GNUNET_free (dl);
+  return GNUNET_SYSERR;
 }
 
 
 /**
- * Force a disconnect from the specified peer. 
+ * Whitelist all peers that we blacklisted; we've passed
+ * the minimum number of friends.
  */
 static void
-force_disconnect (struct PeerList *pl)
+whitelist_peers ()
 {
-  const struct GNUNET_PeerIdentity *peer = &pl->id;
-  struct DisconnectList *dl;
-
-  if (NULL != pl->wh)
+  if (blacklist != NULL)
     {
-      GNUNET_TRANSPORT_blacklist_cancel (pl->wh);
-      pl->wh = NULL;
+      GNUNET_TRANSPORT_blacklist_cancel (blacklist);
+      blacklist = NULL;
     }
-  pl->is_blocked = GNUNET_YES;
-  dl = GNUNET_malloc (sizeof (struct DisconnectList));
-  dl->peer = *peer;
-  GNUNET_CONTAINER_DLL_insert (disconnect_head,
-                              disconnect_tail,
-                              dl);
-  dl->rh = GNUNET_TRANSPORT_blacklist (sched, cfg,                                             
-                                      peer,
-                                      GNUNET_TIME_UNIT_FOREVER_REL,
-                                      GNUNET_TIME_UNIT_FOREVER_REL,
-                                      &disconnect_done,
-                                      dl);
 }
 
 
-
 /**
- * Function called once our request to 'whitelist' a peer
- * has completed.
+ * Function called by core when our attempt to connect succeeded.
  *
- * @param cls our 'struct PeerList'
- * @param tc unused
+ * @param cls the 'struct Peer' for which we issued the connect request
+ * @param success was the request transmitted
  */
 static void
-whitelist_done (void *cls,
-               const struct GNUNET_SCHEDULER_TaskContext *tc)
+connect_completed_callback (void *cls,
+                           int success)
 {
-  struct PeerList *pl = cls;
+  struct Peer *pos = cls;
 
-  pl->wh = NULL;
-  GNUNET_STATISTICS_update (stats,
-                           gettext_noop ("# peers blacklisted"),
-                           -1,
-                           GNUNET_NO);
+  pos->connect_req = NULL;
 }
 
 
 /**
- * Whitelist all peers that we blacklisted; we've passed
- * the minimum number of friends.
+ * Check if an additional connection from the given peer is allowed.
+ * 
+ * @param peer connection to check
+ * @return GNUNET_OK if the connection is allowed
  */
-static void
-whitelist_peers ()
+static int
+is_connection_allowed (struct Peer *peer)
 {
-  struct PeerList *pl;
-  struct DisconnectList *dl;
-
-  /* first, cancel all blacklisting requests */
-  while (NULL != (dl = disconnect_head))
-    {
-      GNUNET_CONTAINER_DLL_remove (disconnect_head,
-                                  disconnect_tail,
-                                  dl);
-      GNUNET_TRANSPORT_blacklist_cancel (dl->rh);
-      GNUNET_free (dl);
-    }
-  /* then, specifically whitelist all peers that we
-     know to have blacklisted */
-  pl = peers;
-  while (pl != NULL)
+  if (0 == memcmp (&my_identity, 
+                  &peer->pid, 
+                  sizeof (struct GNUNET_PeerIdentity)))
+    return GNUNET_SYSERR;       /* disallow connections to self */
+  if (peer->is_friend)
+    return GNUNET_OK;
+  if (GNUNET_YES == friends_only)
     {
-      if (pl->is_blocked)
-       {
-         pl->wh = GNUNET_TRANSPORT_blacklist (sched, cfg,                                              
-                                              &pl->id,
-                                              GNUNET_TIME_UNIT_ZERO,
-                                              GNUNET_TIME_UNIT_FOREVER_REL,
-                                              &whitelist_done,
-                                              pl);
-         pl->is_blocked = GNUNET_NO;
-       }
-      pl = pl->next;
+#if DEBUG_TOPOLOGY
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Determined that `%s' is not allowed to connect (not a friend)\n",
+                 GNUNET_i2s (&peer->pid));
+#endif       
+      return GNUNET_SYSERR;
     }
+  if (friend_count >= minimum_friend_count)
+    return GNUNET_OK;
+#if DEBUG_TOPOLOGY
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+             "Determined that `%s' is not allowed to connect (not enough connected friends)\n",
+             GNUNET_i2s (&peer->pid));
+#endif       
+  return GNUNET_SYSERR;
 }
 
 
 /**
- * Function called by core when our attempt to connect succeeded.
+ * Free all resources associated with the given peer.
+ *
+ * @param cls closure (not used)
+ * @param pid identity of the peer
+ * @param value peer to free
+ * @return GNUNET_YES (always: continue to iterate)
  */
-static void
-connect_completed_callback (void *cls,
-                           const struct GNUNET_SCHEDULER_TaskContext *tc)
+static int
+free_peer (void *cls,
+          const GNUNET_HashCode *pid,
+          void *value)
 {
-  struct PeerList *pos = cls;
-
-  pos->connect_req = NULL;
+  struct Peer *pos = value;
+
+  GNUNET_break (GNUNET_OK == 
+               GNUNET_CONTAINER_multihashmap_remove (peers,
+                                                     pid,
+                                                     pos));
+  if (pos->hello_req != NULL)
+    GNUNET_CORE_notify_transmit_ready_cancel (pos->hello_req);
+  if (pos->connect_req != NULL)
+    GNUNET_CORE_peer_request_connect_cancel (pos->connect_req);              
+  if (pos->hello_delay_task != GNUNET_SCHEDULER_NO_TASK)
+    GNUNET_SCHEDULER_cancel (pos->hello_delay_task);
+  if (pos->greylist_clean_task != GNUNET_SCHEDULER_NO_TASK)
+    GNUNET_SCHEDULER_cancel (pos->greylist_clean_task);
+  GNUNET_free_non_null (pos->hello);   
+  if (pos->filter != NULL)
+    GNUNET_CONTAINER_bloomfilter_free (pos->filter);
+  GNUNET_free (pos);
+  return GNUNET_YES;
 }
 
 
+/**
+ * Discard peer entries for greylisted peers
+ * where the greylisting has expired.
+ *
+ * @param cls 'struct Peer' to greylist
+ * @param tc scheduler context
+ */
+static void
+remove_from_greylist (void *cls,
+                     const struct GNUNET_SCHEDULER_TaskContext *tc);
+
+
 /**
  * Try to connect to the specified peer.
  *
  * @param pos peer to connect to
  */
 static void
-attempt_connect (struct PeerList *pos)
+attempt_connect (struct Peer *pos)
 {
+  struct GNUNET_TIME_Relative rem;
+  
+  if ( (connection_count >= target_connection_count) &&
+       (friend_count >= minimum_friend_count) )
+    return;
+  if (GNUNET_YES == pos->is_connected)
+    return;
+  if (GNUNET_OK != is_connection_allowed (pos))
+    return;
+  if (GNUNET_TIME_absolute_get_remaining (pos->greylisted_until).rel_value > 0)
+    return;
   if (GNUNET_YES == pos->is_friend)
-    pos->blacklisted_until = GNUNET_TIME_relative_to_absolute (BLACKLIST_AFTER_ATTEMPT_FRIEND);
+    rem = GREYLIST_AFTER_ATTEMPT_FRIEND;
   else
-    pos->blacklisted_until = GNUNET_TIME_relative_to_absolute (BLACKLIST_AFTER_ATTEMPT);
+    rem = GREYLIST_AFTER_ATTEMPT;
+  rem = GNUNET_TIME_relative_multiply (rem, connection_count);
+  rem = GNUNET_TIME_relative_divide (rem, target_connection_count);
+  if (pos->connect_attempts > 30)
+    pos->connect_attempts = 30;
+  rem = GNUNET_TIME_relative_multiply (rem, 1 << (++pos->connect_attempts));
+  rem = GNUNET_TIME_relative_max (rem,
+                                 GREYLIST_AFTER_ATTEMPT_MIN);
+  rem = GNUNET_TIME_relative_min (rem,
+                                 GREYLIST_AFTER_ATTEMPT_MAX);
+  pos->greylisted_until = GNUNET_TIME_relative_to_absolute (rem);
+  if (pos->greylist_clean_task != GNUNET_SCHEDULER_NO_TASK)
+    GNUNET_SCHEDULER_cancel (pos->greylist_clean_task);
+  pos->greylist_clean_task 
+    = GNUNET_SCHEDULER_add_delayed (rem,
+                                   &remove_from_greylist,
+                                   pos);
 #if DEBUG_TOPOLOGY
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-             "Asking core to connect to `%s'\n",
-             GNUNET_i2s (&pos->id));
+             "Asking  to connect to `%s'\n",
+             GNUNET_i2s (&pos->pid));
 #endif
   GNUNET_STATISTICS_update (stats,
                            gettext_noop ("# connect requests issued to core"),
                            1,
                            GNUNET_NO);
-  pos->connect_req = GNUNET_CORE_peer_request_connect (sched, cfg,
+  pos->connect_req = GNUNET_CORE_peer_request_connect (handle,
                                                       GNUNET_TIME_UNIT_MINUTES,
-                                                      &pos->id,
+                                                      &pos->pid,
                                                       &connect_completed_callback,
                                                       pos);
 }
 
 
 /**
- * Find a peer in our linked list.  
- * FIXME: should probably use a hash map instead.
+ * Discard peer entries for greylisted peers
+ * where the greylisting has expired.
+ *
+ * @param cls 'struct Peer' to greylist
+ * @param tc scheduler context
  */
-struct PeerList *
-find_peer (const struct GNUNET_PeerIdentity * peer)
+static void
+remove_from_greylist (void *cls,
+                     const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  struct PeerList *pos;
+  struct Peer *pos = cls;
+  struct GNUNET_TIME_Relative rem;
 
-  pos = peers;
-  while (pos != NULL)
+  pos->greylist_clean_task = GNUNET_SCHEDULER_NO_TASK;
+  rem = GNUNET_TIME_absolute_get_remaining (pos->greylisted_until);
+  if (rem.rel_value == 0)
     {
-      if (0 == memcmp (&pos->id, peer, sizeof (struct GNUNET_PeerIdentity)))
-       return pos;
-      pos = pos->next;
+      attempt_connect (pos);
     }
-  return NULL;
-}
-
-
-/**
- * Check if an additional connection from the given peer is allowed.
- */
-static int
-is_connection_allowed (struct PeerList *peer)
-{
-  if (0 == memcmp (&my_identity, &peer->id, sizeof (struct GNUNET_PeerIdentity)))
-    return GNUNET_SYSERR;       /* disallow connections to self */
-  if (peer->is_friend)
-    return GNUNET_OK;
-  if (GNUNET_YES == friends_only)
+  else
     {
-#if DEBUG_TOPOLOGY
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                 "Determined that `%s' is not allowed to connect (not a friend)\n",
-                 GNUNET_i2s (&peer->id));
-#endif       
-      return GNUNET_SYSERR;
+      pos->greylist_clean_task 
+       = GNUNET_SCHEDULER_add_delayed (rem,
+                                       &remove_from_greylist,
+                                       pos);
+    }
+  if ( (GNUNET_NO == pos->is_friend) &&
+       (GNUNET_NO == pos->is_connected) )
+    {
+      free_peer (NULL, &pos->pid.hashPubKey, pos);
+      return;
     }
-  if (friend_count >= minimum_friend_count)
-    return GNUNET_OK;
-#if DEBUG_TOPOLOGY
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-             "Determined that `%s' is not allowed to connect (not enough connected friends)\n",
-             GNUNET_i2s (&peer->id));
-#endif       
-  return GNUNET_SYSERR;
 }
 
 
@@ -470,16 +465,16 @@ is_connection_allowed (struct PeerList *peer)
  * @param is_friend is the new entry for a friend?
  * @return the new entry
  */
-static struct PeerList *
+static struct Peer *
 make_peer (const struct
           GNUNET_PeerIdentity * peer,
           const struct GNUNET_HELLO_Message *hello,
           int is_friend)
 {
-  struct PeerList *ret;
+  struct Peer *ret;
   
-  ret = GNUNET_malloc (sizeof (struct PeerList));
-  ret->id = *peer;
+  ret = GNUNET_malloc (sizeof (struct Peer));
+  ret->pid = *peer;
   ret->is_friend = is_friend;
   if (hello != NULL)
     {
@@ -487,58 +482,22 @@ make_peer (const struct
       memcpy (ret->hello, hello,
              GNUNET_HELLO_size (hello));
     }
-  ret->next = peers;
-  peers = ret;
+  GNUNET_break (GNUNET_OK ==
+               GNUNET_CONTAINER_multihashmap_put (peers,
+                                                  &peer->hashPubKey,
+                                                  ret,
+                                                  GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
   return ret;
 }
 
 
-/**
- * Free all resources associated with the given peer.
- *
- * @param peer peer to free
- */
-static void
-free_peer (struct PeerList *peer)
-{
-  struct PeerList *pos;
-  struct PeerList *prev;
-  
-  prev = NULL;
-  pos = peers;
-  while (peer != pos)
-    {
-      prev = pos;
-      pos = pos->next;
-    }
-  GNUNET_assert (pos != NULL);
-   if (prev == NULL)
-     peers = pos->next;
-   else
-     prev->next = pos->next;
-   if (pos->hello_req != NULL)
-     GNUNET_CORE_notify_transmit_ready_cancel (pos->hello_req);
-   if (pos->wh != NULL)
-     GNUNET_TRANSPORT_blacklist_cancel (pos->wh);
-   if (pos->connect_req != NULL)
-     GNUNET_CORE_peer_request_connect_cancel (pos->connect_req);             
-   if (pos->hello_delay_task != GNUNET_SCHEDULER_NO_TASK)
-     GNUNET_SCHEDULER_cancel (sched,
-                             pos->hello_delay_task);
-   GNUNET_free_non_null (pos->hello);   
-   if (pos->filter != NULL)
-     GNUNET_CONTAINER_bloomfilter_free (peer->filter);
-   GNUNET_free (pos);
-}
-
-
 /**
  * Setup bloom filter for the given peer entry.
  *
  * @param peer entry to initialize
  */
 static void
-setup_filter (struct PeerList *peer)
+setup_filter (struct Peer *peer)
 {
   /* 2^{-5} chance of not sending a HELLO to a peer is
      acceptably small (if the filter is 50% full);
@@ -550,14 +509,14 @@ setup_filter (struct PeerList *peer)
   peer->filter = GNUNET_CONTAINER_bloomfilter_load (NULL, 64, 5);
   peer->filter_expiration = GNUNET_TIME_relative_to_absolute (HELLO_ADVERTISEMENT_MIN_REPEAT_FREQUENCY);
   /* never send a peer its own HELLO */
-  GNUNET_CONTAINER_bloomfilter_add (peer->filter, &peer->id.hashPubKey);
+  GNUNET_CONTAINER_bloomfilter_add (peer->filter, &peer->pid.hashPubKey);
 }
 
 
 /**
  * Function to fill send buffer with HELLO.
  *
- * @param cls 'struct PeerList' of the target peer
+ * @param cls 'struct Peer' 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
@@ -568,6 +527,74 @@ hello_advertising_ready (void *cls,
                         void *buf);
 
 
+
+
+/**
+ * Closure for 'find_advertisable_hello'.
+ */
+struct FindAdvHelloContext {
+
+  /**
+   * Peer we want to advertise to.
+   */
+  struct Peer *peer;
+
+  /**
+   * Where to store the result (peer selected for advertising).
+   */
+  struct Peer *result;
+
+  /**
+   * Maximum HELLO size we can use right now.
+   */
+  size_t max_size;
+
+  struct GNUNET_TIME_Relative next_adv;
+};
+
+
+/**
+ * Find a peer that would be reasonable for advertising.
+ *
+ * @param cls closure
+ * @param pid identity of a peer
+ * @param value 'struct Peer*' for the peer we are considering 
+ * @return GNUNET_YES (continue iteration)
+ */
+static int
+find_advertisable_hello (void *cls,
+                        const GNUNET_HashCode *pid,
+                        void *value)
+{
+  struct FindAdvHelloContext *fah = cls;
+  struct Peer *pos = value;
+  struct GNUNET_TIME_Relative rst_time;
+  size_t hs;
+
+  if (pos == fah->peer)
+    return GNUNET_YES;
+  if (pos->hello == NULL)
+    return GNUNET_YES;
+  rst_time = GNUNET_TIME_absolute_get_remaining (pos->filter_expiration);
+  if (0 == rst_time.rel_value)
+    {
+      /* time to discard... */
+      GNUNET_CONTAINER_bloomfilter_free (pos->filter);
+      setup_filter (pos);
+    }
+  fah->next_adv = GNUNET_TIME_relative_min (rst_time,
+                                           fah->next_adv);
+  hs = GNUNET_HELLO_size (pos->hello);
+  if (hs > fah->max_size)
+    return GNUNET_YES;
+  if (GNUNET_NO ==
+      GNUNET_CONTAINER_bloomfilter_test (pos->filter,
+                                        &fah->peer->pid.hashPubKey))
+    fah->result = pos;    
+  return GNUNET_YES;
+}
+
+
 /**
  * Calculate when we would like to send the next HELLO to this
  * peer and ask for it.
@@ -579,62 +606,42 @@ static void
 schedule_next_hello (void *cls,
                     const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  struct PeerList *pl = cls;
-  struct PeerList *pos;
-  struct PeerList *next;
-  uint16_t next_want;
-  struct GNUNET_TIME_Relative next_adv;
-  struct GNUNET_TIME_Relative rst_time;
-  
+  struct Peer *pl = cls;
+  struct FindAdvHelloContext fah;
+  size_t next_want;
+  struct GNUNET_TIME_Relative delay;
   pl->hello_delay_task = GNUNET_SCHEDULER_NO_TASK;
   if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
     return; /* we're out of here */
-  next_want = 0;
-  next_adv = GNUNET_TIME_UNIT_FOREVER_REL;
+  if (pl->hello_req != NULL)
+    return; /* did not finish sending the previous one */
   /* find applicable HELLOs */
-  next = peers;
-  while (NULL != (pos = next))
-    {
-      next = pos->next;
-      if (pos->hello == NULL)
-       continue;
-      rst_time = GNUNET_TIME_absolute_get_remaining (pos->filter_expiration);
-      if (0 == rst_time.value)
-       {
-         /* time to discard... */
-         GNUNET_CONTAINER_bloomfilter_free (pos->filter);
-         setup_filter (pos);
-       }
-      else
-       {
-         if (rst_time.value < next_adv.value)
-           next_want = GNUNET_HELLO_size (pos->hello);
-         next_adv = GNUNET_TIME_relative_min (rst_time,
-                                              next_adv);         
-       }
-      if (GNUNET_NO ==
-         GNUNET_CONTAINER_bloomfilter_test (pos->filter,
-                                            &pl->id.hashPubKey))
-       break;
-    }
-  if (pos != NULL)  
-    next_adv = GNUNET_TIME_absolute_get_remaining (pl->next_hello_allowed);
-  if (next_adv.value == 0)
+  fah.peer = pl;
+  fah.result = NULL;
+  fah.max_size = GNUNET_SERVER_MAX_MESSAGE_SIZE - 1;
+  fah.next_adv = GNUNET_TIME_UNIT_FOREVER_REL;
+  GNUNET_CONTAINER_multihashmap_iterate (peers,
+                                        &find_advertisable_hello,
+                                        &fah);
+  pl->hello_delay_task 
+    = GNUNET_SCHEDULER_add_delayed (fah.next_adv,
+                                   &schedule_next_hello,
+                                   pl);
+  if (fah.result == NULL)
+    return;   
+  next_want = GNUNET_HELLO_size (fah.result->hello);
+  delay = GNUNET_TIME_absolute_get_remaining (pl->next_hello_allowed);
+  if (delay.rel_value == 0)
     {
       /* now! */
       pl->hello_req = GNUNET_CORE_notify_transmit_ready (handle, 0,
-                                                        next_adv,
-                                                        &pl->id,
+                                                        GNUNET_CONSTANTS_SERVICE_TIMEOUT,
+                                                        &pl->pid,
                                                         next_want,
                                                         &hello_advertising_ready,
                                                         pl);
-      return;
     }
-  pl->hello_delay_task 
-    = GNUNET_SCHEDULER_add_delayed (sched,
-                                   next_adv,
-                                   &schedule_next_hello,
-                                   pl);
 }
 
 
@@ -642,25 +649,38 @@ schedule_next_hello (void *cls,
  * Cancel existing requests for sending HELLOs to this peer
  * and recalculate when we should send HELLOs to it based
  * on our current state (something changed!).
+ *
+ * @param cls closure, 'struct Peer' to skip, or NULL
+ * @param pid identity of a peer
+ * @param value 'struct Peer*' for the peer
+ * @return GNUNET_YES (always)
  */
-static void
-reschedule_hellos (struct PeerList *peer)
+static int
+reschedule_hellos (void *cls,
+                  const GNUNET_HashCode *pid,
+                  void *value)
 {
+  struct Peer *peer = value;
+  struct Peer *skip = cls;
+
+  if (skip == peer)
+    return GNUNET_YES;
+  if (! peer->is_connected) 
+    return GNUNET_YES;
   if (peer->hello_req != NULL)
     {
       GNUNET_CORE_notify_transmit_ready_cancel (peer->hello_req);
       peer->hello_req = NULL;
     }
-   if (peer->hello_delay_task != GNUNET_SCHEDULER_NO_TASK)
-     {
-       GNUNET_SCHEDULER_cancel (sched,
-                               peer->hello_delay_task);
-       peer->hello_delay_task = GNUNET_SCHEDULER_NO_TASK;
-     }
-   peer->hello_delay_task 
-     = GNUNET_SCHEDULER_add_now (sched,
-                                &schedule_next_hello,
-                                peer);
+  if (peer->hello_delay_task != GNUNET_SCHEDULER_NO_TASK)
+    {
+      GNUNET_SCHEDULER_cancel (peer->hello_delay_task);
+      peer->hello_delay_task = GNUNET_SCHEDULER_NO_TASK;
+    }
+  peer->hello_delay_task 
+    = GNUNET_SCHEDULER_add_now (&schedule_next_hello,
+                               peer);
+  return GNUNET_YES;
 }
 
 
@@ -669,51 +689,42 @@ reschedule_hellos (struct PeerList *peer)
  *
  * @param cls closure
  * @param peer peer identity this notification is about
- * @param latency reported latency of the connection with 'other'
- * @param distance reported distance (DV) to 'other' 
+ * @param atsi performance data
  */
 static void 
 connect_notify (void *cls,
                const struct
                GNUNET_PeerIdentity * peer,
-               struct GNUNET_TIME_Relative latency,
-               uint32_t distance)
+               const struct GNUNET_TRANSPORT_ATS_Information *atsi)
 {
-  struct PeerList *pos;
+  struct Peer *pos;
 
 #if DEBUG_TOPOLOGY
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Core told us that we are connecting to `%s'\n",
              GNUNET_i2s (peer));
 #endif
+  if (0 == memcmp(&my_identity, peer, sizeof(struct GNUNET_PeerIdentity)))
+    return;
+
   connection_count++;
   GNUNET_STATISTICS_set (stats,
                         gettext_noop ("# peers connected"),
                         connection_count,
                         GNUNET_NO);
-  pos = find_peer (peer);
+  pos = GNUNET_CONTAINER_multihashmap_get (peers, &peer->hashPubKey);
   if (pos == NULL)    
     {
       pos = make_peer (peer, NULL, GNUNET_NO);
-      if (GNUNET_OK != is_connection_allowed (pos))
-       {
-         GNUNET_assert (pos->is_friend == GNUNET_NO);
-         pos->is_connected = GNUNET_YES;
-#if DEBUG_TOPOLOGY
-         GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                     "Connection to `%s' is forbidden, forcing disconnect!\n",
-                     GNUNET_i2s (peer));
-#endif       
-         force_disconnect (pos);
-         return;
-       }
+      GNUNET_break (GNUNET_OK == is_connection_allowed (pos));
     }
   else
     {
       GNUNET_assert (GNUNET_NO == pos->is_connected);
-      pos->blacklisted_until.value = 0; /* remove blacklisting */
+      pos->greylisted_until.abs_value = 0; /* remove greylisting */
     }
   pos->is_connected = GNUNET_YES;
+  pos->connect_attempts = 0; /* re-set back-off factor */
   if (pos->is_friend)
     {
       if ( (friend_count == minimum_friend_count - 1) &&
@@ -722,57 +733,30 @@ connect_notify (void *cls,
       friend_count++;
       GNUNET_STATISTICS_set (stats,
                             gettext_noop ("# friends connected"),
-                            connection_count,
+                            friend_count,
                             GNUNET_NO);
     }
-  reschedule_hellos (pos);
-}
-
-
-/**
- * Disconnect from all non-friends (we're below quota).
- */
-static void
-drop_non_friends ()
-{
-  struct PeerList *pos;
-
-  pos = peers;
-  while (pos != NULL)
-    {
-      if ( (GNUNET_NO == pos->is_friend) &&
-          (GNUNET_YES == pos->is_connected) )
-       {
-#if DEBUG_TOPOLOGY
-         GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                     "Connection to `%s' is not from a friend, forcing disconnect!\n",
-                     GNUNET_i2s (&pos->id));
-#endif       
-         force_disconnect (pos);
-       }
-      pos = pos->next;
-    }
+  reschedule_hellos (NULL, &peer->hashPubKey, pos);
 }
 
 
 /**
  * Try to add more peers to our connection set.
+ *
+ * @param cls closure, not used
+ * @param pid identity of a peer
+ * @param value 'struct Peer*' for the peer
+ * @return GNUNET_YES (continue to iterate)
  */
-static void
-try_add_peers ()
+static int
+try_add_peers (void *cls,
+              const GNUNET_HashCode *pid,
+              void *value)
 {
-  struct PeerList *pos;
+  struct Peer *pos = value;
 
-  pos = peers;
-  while (pos != NULL)
-    {
-      if ( (GNUNET_TIME_absolute_get_remaining (pos->blacklisted_until).value == 0) &&
-          ( (GNUNET_YES == pos->is_friend) ||
-            (friend_count >= minimum_friend_count) ) &&
-          (GNUNET_YES != pos->is_connected) )
-       attempt_connect (pos);
-      pos = pos->next;
-    }
+  attempt_connect (pos);
+  return GNUNET_YES;
 }
 
 
@@ -787,14 +771,17 @@ disconnect_notify (void *cls,
                   const struct
                   GNUNET_PeerIdentity * peer)
 {
-  struct PeerList *pos;
+  struct Peer *pos;
+
+  if (0 == memcmp(&my_identity, peer, sizeof(struct GNUNET_PeerIdentity)))
+    return;
 #if DEBUG_TOPOLOGY
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Core told us that we disconnected from `%s'\n",
              GNUNET_i2s (peer));
 #endif       
-  pos = find_peer (peer);
+  pos = GNUNET_CONTAINER_multihashmap_get (peers,
+                                          &peer->hashPubKey);
   if (pos == NULL)
     {
       GNUNET_break (0);
@@ -815,21 +802,18 @@ disconnect_notify (void *cls,
       friend_count--; 
       GNUNET_STATISTICS_set (stats,
                             gettext_noop ("# friends connected"),
-                            connection_count,
+                            friend_count,
                             GNUNET_NO);
     }
   if ( (connection_count < target_connection_count) ||
        (friend_count < minimum_friend_count) )
-    try_add_peers ();   
-  if (friend_count < minimum_friend_count)
-    {
-      /* disconnect from all non-friends */
-#if DEBUG_TOPOLOGY
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                 "Not enough friendly connections, dropping all non-friend connections\n");
-#endif       
-      drop_non_friends ();
-    }
+    GNUNET_CONTAINER_multihashmap_iterate (peers,
+                                          &try_add_peers,
+                                          NULL);
+  if ( (friend_count < minimum_friend_count) &&
+       (blacklist == NULL) )
+    blacklist = GNUNET_TRANSPORT_blacklist (cfg,
+                                           &blacklist_check, NULL);
 }
 
 
@@ -847,7 +831,8 @@ static int
 address_iterator (void *cls,
                  const char *tname,
                  struct GNUNET_TIME_Absolute expiration,
-                 const void *addr, size_t addrlen)
+                 const void *addr, 
+                 uint16_t addrlen)
 {
   int *flag = cls;
   *flag = GNUNET_YES;
@@ -858,17 +843,24 @@ address_iterator (void *cls,
 /**
  * We've gotten a HELLO from another peer.  Consider it for
  * advertising.
+ *
+ * @param hello the HELLO we got
  */
 static void
 consider_for_advertising (const struct GNUNET_HELLO_Message *hello)
 {
   int have_address;
   struct GNUNET_PeerIdentity pid;
-  struct PeerList *peer;
-  struct PeerList *pos;
+  struct GNUNET_TIME_Absolute dt;
+  struct GNUNET_HELLO_Message *nh;
+  struct Peer *peer;
   uint16_t size;
 
-  GNUNET_break (GNUNET_OK == GNUNET_HELLO_get_id (hello, &pid));
+  if (GNUNET_OK != GNUNET_HELLO_get_id (hello, &pid))
+    {
+       GNUNET_break (0);
+       return;
+    }
   if (0 == memcmp (&pid,
                   &my_identity,
                   sizeof (struct GNUNET_PeerIdentity)))
@@ -880,50 +872,64 @@ consider_for_advertising (const struct GNUNET_HELLO_Message *hello)
                                  &have_address);
   if (GNUNET_NO == have_address)
     return; /* no point in advertising this one... */
-  peer = find_peer (&pid);
+  peer = GNUNET_CONTAINER_multihashmap_get (peers,
+                                           &pid.hashPubKey);
   if (peer == NULL)
-    peer = make_peer (&pid, hello, GNUNET_NO);
-  // FIXME: check if 'hello' is any different from peer->hello?
+    {
+      peer = make_peer (&pid, hello, GNUNET_NO);
+    }
+  else if (peer->hello != NULL)
+    {
+      dt = GNUNET_HELLO_equals (peer->hello,
+                               hello,
+                               GNUNET_TIME_absolute_get());
+      if (dt.abs_value == GNUNET_TIME_UNIT_FOREVER_ABS.abs_value)
+       return; /* nothing new here */
+    }
 #if DEBUG_TOPOLOGY
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Found `%s' from peer `%s' for advertising\n",
              "HELLO",
              GNUNET_i2s (&pid));
 #endif 
-  size = GNUNET_HELLO_size (hello);
-  GNUNET_free_non_null (peer->hello);
-  peer->hello = GNUNET_malloc (size);
-  memcpy (peer->hello, hello, size);
+  if (peer->hello != NULL)
+    {
+      nh = GNUNET_HELLO_merge (peer->hello,
+                              hello);
+      GNUNET_free (peer->hello);
+      peer->hello = nh;
+    }
+  else
+    {
+      size = GNUNET_HELLO_size (hello);
+      peer->hello = GNUNET_malloc (size);
+      memcpy (peer->hello, hello, size);
+    }
   if (peer->filter != NULL)
     GNUNET_CONTAINER_bloomfilter_free (peer->filter);
   setup_filter (peer);
   /* since we have a new HELLO to pick from, re-schedule all
      HELLO requests that are not bound by the HELLO send rate! */
-  pos = peers;
-  while (NULL != pos)
-    {
-      if (pos != peer) 
-       {
-         if ( (pos->is_connected) &&
-              (GNUNET_TIME_absolute_get_remaining (pos->next_hello_allowed).value <= HELLO_ADVERTISEMENT_MIN_FREQUENCY.value) )
-           reschedule_hellos (pos);    
-       }
-      pos = pos->next;
-    }
+  GNUNET_CONTAINER_multihashmap_iterate (peers,
+                                        &reschedule_hellos,
+                                        peer);
 }
 
 
 /**
- * Peerinfo calls this function to let us know about a possible peer
+ * PEERINFO calls this function to let us know about a possible peer
  * that we might want to connect to.
+ *
+ * @param cls closure (not used)
+ * @param peer potential peer to connect to
+ * @param hello HELLO for this peer (or NULL)
  */
 static void
 process_peer (void *cls,
              const struct GNUNET_PeerIdentity *peer,
-             const struct GNUNET_HELLO_Message *hello,
-             uint32_t trust)
+             const struct GNUNET_HELLO_Message *hello)
 {
-  struct PeerList *pos;
+  struct Peer *pos;
 
   GNUNET_assert (peer != NULL);
   if (0 == memcmp (&my_identity,
@@ -932,7 +938,9 @@ process_peer (void *cls,
   if (hello == NULL)
     {
       /* free existing HELLO, if any */
-      if (NULL != (pos = find_peer (peer)))
+      pos = GNUNET_CONTAINER_multihashmap_get (peers,
+                                              &peer->hashPubKey);
+      if (NULL != pos)
        {
          GNUNET_free_non_null (pos->hello);
          pos->hello = NULL;
@@ -943,21 +951,17 @@ process_peer (void *cls,
            }
          if ( (! pos->is_connected) &&
               (! pos->is_friend) &&
-              (0 == GNUNET_TIME_absolute_get_remaining (pos->blacklisted_until).value) )
-           free_peer (pos);
+              (0 == GNUNET_TIME_absolute_get_remaining (pos->greylisted_until).rel_value) )
+           free_peer (NULL, &pos->pid.hashPubKey, pos);
        }
       return;
     }
   consider_for_advertising (hello);
-  pos = find_peer (peer);  
+  pos = GNUNET_CONTAINER_multihashmap_get (peers,
+                                          &peer->hashPubKey);
   if (pos == NULL)
     pos = make_peer (peer, hello, GNUNET_NO);
   GNUNET_assert (NULL != pos);
-#if DEBUG_TOPOLOGY
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-             "Considering connecting to peer `%s'\n",
-             GNUNET_i2s (peer));
-#endif 
   if (GNUNET_YES == pos->is_connected)
     {
 #if DEBUG_TOPOLOGY
@@ -967,49 +971,21 @@ process_peer (void *cls,
 #endif 
       return;
     }
-  if (GNUNET_TIME_absolute_get_remaining (pos->blacklisted_until).value > 0)
+  if (GNUNET_TIME_absolute_get_remaining (pos->greylisted_until).rel_value > 0)
     {
 #if DEBUG_TOPOLOGY
       GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
                  "Already tried peer `%s' recently\n",
                  GNUNET_i2s (peer));
 #endif 
-      return; /* peer still blacklisted */
-    }
-  if ( (GNUNET_YES == pos->is_friend) ||
-       (GNUNET_YES != friends_only) ||    
-       (friend_count >= minimum_friend_count) )
-    attempt_connect (pos);
-}
-
-
-/**
- * Discard peer entries for blacklisted peers
- * where the blacklisting has expired.
- */
-static void
-discard_old_blacklist_entries (void *cls,
-                              const struct GNUNET_SCHEDULER_TaskContext *tc)
-{
-  struct PeerList *pos;
-  struct PeerList *next;
-
-  if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
-    return;
-  next = peers;
-  while (NULL != (pos = next))
-    {
-      next = pos->next;
-      if ( (GNUNET_NO == pos->is_friend) &&
-          (GNUNET_NO == pos->is_connected) &&
-          (GNUNET_NO == pos->is_blocked) &&
-          (0 == GNUNET_TIME_absolute_get_remaining (pos->blacklisted_until).value) )
-       free_peer (pos);
+      return; /* peer still greylisted */
     }
-  GNUNET_SCHEDULER_add_delayed (sched,
-                               BLACKLIST_AFTER_ATTEMPT,
-                               &discard_old_blacklist_entries,
-                               NULL);
+#if DEBUG_TOPOLOGY
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+             "Considering connecting to peer `%s'\n",
+             GNUNET_i2s (peer));
+#endif 
+  attempt_connect (pos);
 }
 
 
@@ -1035,7 +1011,7 @@ core_init (void *cls,
     {
       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                  _("Failed to connect to core service, can not manage topology!\n"));
-      GNUNET_SCHEDULER_shutdown (sched);
+      GNUNET_SCHEDULER_shutdown ();
       return;
     }
   handle = server;
@@ -1045,12 +1021,7 @@ core_init (void *cls,
              "I am peer `%s'\n",
              GNUNET_i2s (my_id));
 #endif         
-  GNUNET_SCHEDULER_add_delayed (sched,
-                               BLACKLIST_AFTER_ATTEMPT,
-                               &discard_old_blacklist_entries,
-                               NULL);
-  peerinfo_notify = GNUNET_PEERINFO_notify (cfg, sched,
-                                           &process_peer,
+  peerinfo_notify = GNUNET_PEERINFO_notify (cfg, &process_peer,
                                            NULL);
 }
 
@@ -1068,7 +1039,7 @@ read_friends_file (const struct GNUNET_CONFIGURATION_Handle *cfg)
   struct stat frstat;
   struct GNUNET_CRYPTO_HashAsciiEncoded enc;
   unsigned int entries_found;
-  struct PeerList *fl;
+  struct Peer *fl;
 
   if (GNUNET_OK !=
       GNUNET_CONFIGURATION_get_value_filename (cfg,
@@ -1083,17 +1054,16 @@ read_friends_file (const struct GNUNET_CONFIGURATION_Handle *cfg)
       return;
     }
   if (GNUNET_OK != GNUNET_DISK_file_test (fn))
-    GNUNET_DISK_fn_write (fn, NULL, 0, GNUNET_DISK_PERM_USER_READ
-        | GNUNET_DISK_PERM_USER_WRITE);
+    GNUNET_DISK_fn_write (fn, NULL, 0, 
+                         GNUNET_DISK_PERM_USER_READ
+                         | GNUNET_DISK_PERM_USER_WRITE);
   if (0 != STAT (fn, &frstat))
     {
       if ((friends_only) || (minimum_friend_count > 0))
-        {
-          GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                     _("Could not read friends list `%s'\n"), fn);
-         GNUNET_free (fn);
-          return;
-        }
+       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                   _("Could not read friends list `%s'\n"), fn);
+      GNUNET_free (fn);
+      return;
     }
   if (frstat.st_size == 0)
     {
@@ -1104,6 +1074,13 @@ read_friends_file (const struct GNUNET_CONFIGURATION_Handle *cfg)
       return;
     }
   data = GNUNET_malloc_large (frstat.st_size);
+  if (data == NULL)
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                 _("Failed to read friends list from `%s': out of memory\n"), fn);
+      GNUNET_free (fn);
+      return;
+    }
   if (frstat.st_size !=
       GNUNET_DISK_fn_read (fn, data, frstat.st_size))
     {
@@ -1115,19 +1092,19 @@ read_friends_file (const struct GNUNET_CONFIGURATION_Handle *cfg)
     }
   entries_found = 0;
   pos = 0;
-  while ((pos < frstat.st_size) && isspace (data[pos]))
+  while ((pos < frstat.st_size) && isspace ( (unsigned char) data[pos]))
     pos++;
   while ((frstat.st_size >= sizeof (struct GNUNET_CRYPTO_HashAsciiEncoded)) &&
         (pos <= frstat.st_size - sizeof (struct GNUNET_CRYPTO_HashAsciiEncoded)))
     {
       memcpy (&enc, &data[pos], sizeof (struct GNUNET_CRYPTO_HashAsciiEncoded));
-      if (!isspace (enc.encoding[sizeof (struct GNUNET_CRYPTO_HashAsciiEncoded) - 1]))
+      if (!isspace ( (unsigned char) enc.encoding[sizeof (struct GNUNET_CRYPTO_HashAsciiEncoded) - 1]))
        {
          GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
                      _("Syntax error in topology specification at offset %llu, skipping bytes.\n"),
                      (unsigned long long) pos);
          pos++;
-         while ((pos < frstat.st_size) && (!isspace (data[pos])))
+         while ((pos < frstat.st_size) && (!isspace ( (unsigned char) data[pos])))
            pos++;
          continue;
        }
@@ -1151,7 +1128,7 @@ read_friends_file (const struct GNUNET_CONFIGURATION_Handle *cfg)
                              GNUNET_YES);
              GNUNET_log (GNUNET_ERROR_TYPE_INFO,
                          _("Found friend `%s' in configuration\n"),
-                         GNUNET_i2s (&fl->id));
+                         GNUNET_i2s (&fl->pid));
            }
          else
            {
@@ -1161,7 +1138,7 @@ read_friends_file (const struct GNUNET_CONFIGURATION_Handle *cfg)
            }
        }
       pos = pos + sizeof (struct GNUNET_CRYPTO_HashAsciiEncoded);
-      while ((pos < frstat.st_size) && isspace (data[pos]))
+      while ((pos < frstat.st_size) && isspace ( (unsigned char) data[pos]))
        pos++;
     }
   GNUNET_free (data);
@@ -1193,8 +1170,7 @@ read_friends_file (const struct GNUNET_CONFIGURATION_Handle *cfg)
  * @param other the other peer involved (sender or receiver, NULL
  *        for loopback messages where we are both sender and receiver)
  * @param message the actual HELLO message
- * @param latency reported latency of the connection with 'other'
- * @param distance reported distance (DV) to 'other' 
+ * @param atsi performance data
  * @return GNUNET_OK to keep the connection open,
  *         GNUNET_SYSERR to close it (signal serious error)
  */
@@ -1203,19 +1179,45 @@ handle_encrypted_hello (void *cls,
                        const struct GNUNET_PeerIdentity * other,
                        const struct GNUNET_MessageHeader *
                        message,
-                       struct GNUNET_TIME_Relative latency,
-                       uint32_t distance)
+                       const struct GNUNET_TRANSPORT_ATS_Information *atsi)
 {
+  struct Peer *peer;
+  struct GNUNET_PeerIdentity pid;
+
 #if DEBUG_TOPOLOGY
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Received encrypted `%s' from peer `%s'",
              "HELLO",
              GNUNET_i2s (other));
 #endif         
+  if (GNUNET_OK !=
+      GNUNET_HELLO_get_id ((const struct GNUNET_HELLO_Message*) message,
+                          &pid))
+    {
+      GNUNET_break_op (0);
+      return GNUNET_SYSERR;
+    }
   GNUNET_STATISTICS_update (stats,
                            gettext_noop ("# HELLO messages received"),
                            1,
                            GNUNET_NO);
+  peer = GNUNET_CONTAINER_multihashmap_get (peers,
+                                           &pid.hashPubKey);
+  if (peer == NULL)
+    {
+      if ( (GNUNET_YES == friends_only) ||
+          (friend_count < minimum_friend_count) )
+       return GNUNET_OK;      
+    }
+  else
+    {
+      if ( (GNUNET_YES != peer->is_friend) &&
+          (GNUNET_YES == friends_only) )
+       return GNUNET_OK;
+      if ( (GNUNET_YES != peer->is_friend) &&
+          (friend_count < minimum_friend_count) )
+       return GNUNET_OK;      
+    }
   if (transport != NULL)
     GNUNET_TRANSPORT_offer_hello (transport,
                                  message);
@@ -1226,7 +1228,7 @@ handle_encrypted_hello (void *cls,
 /**
  * Function to fill send buffer with HELLO.
  *
- * @param cls 'struct PeerList' of the target peer
+ * @param cls 'struct Peer' 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
@@ -1236,63 +1238,41 @@ hello_advertising_ready (void *cls,
                         size_t size,
                         void *buf)
 {
-  struct PeerList *pl = cls;
-  struct PeerList *pos; 
-  struct PeerList *next;
-  uint16_t want;
-  size_t hs;
+  struct Peer *pl = cls;
+  struct FindAdvHelloContext fah;
+  size_t want;
 
   pl->hello_req = NULL;
-#if DEBUG_TOPOLOGY
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-             "Data solicited for `%s', considering sending `%s'",
-             GNUNET_i2s (&pl->id),
-             "HELLO");
-#endif         
   /* find applicable HELLOs */
-  next = peers;
-  while (NULL != (pos = next))
-    {
-      next = pos->next;
-      if (pos->hello == NULL)
-       continue;
-      if (0 == GNUNET_TIME_absolute_get_remaining (pos->filter_expiration).value)
-       {
-         /* time to discard... */
-         GNUNET_CONTAINER_bloomfilter_free (pos->filter);
-         setup_filter (pos);
-       }
-      if (GNUNET_NO ==
-         GNUNET_CONTAINER_bloomfilter_test (pos->filter,
-                                            &pl->id.hashPubKey))
-       break;
-    }
+  fah.peer = pl;
+  fah.result = NULL;
+  fah.max_size = size;
+  fah.next_adv = GNUNET_TIME_UNIT_FOREVER_REL;
+  GNUNET_CONTAINER_multihashmap_iterate (peers,
+                                        &find_advertisable_hello,
+                                        &fah);
   want = 0;
-  if (pos != NULL)
+  if (fah.result != NULL)
     {
-      hs = GNUNET_HELLO_size (pos->hello);
-      if (hs < size)
-       {
-         want = hs;
-         memcpy (buf, pos->hello, want);
-         GNUNET_CONTAINER_bloomfilter_add (pos->filter,
-                                           &pl->id.hashPubKey);
+      want = GNUNET_HELLO_size (fah.result->hello);
+      GNUNET_assert (want <= size);
+      memcpy (buf, fah.result->hello, want);
+      GNUNET_CONTAINER_bloomfilter_add (fah.result->filter,
+                                       &pl->pid.hashPubKey);
 #if DEBUG_TOPOLOGY
-         GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                     "Sending %u bytes of `%s's",
-                     (unsigned int) want,
-                     "HELLO");
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Sending `%s' with %u bytes",
+                 "HELLO",
+                 (unsigned int) want);
 #endif         
-         GNUNET_STATISTICS_update (stats,
-                                   gettext_noop ("# HELLO messages gossipped"),
-                                   1,
-                                   GNUNET_NO);
-       }
+      GNUNET_STATISTICS_update (stats,
+                               gettext_noop ("# HELLO messages gossipped"),
+                               1,
+                               GNUNET_NO);    
     }
   pl->next_hello_allowed = GNUNET_TIME_relative_to_absolute (HELLO_ADVERTISEMENT_MIN_FREQUENCY);
   pl->hello_delay_task 
-    = GNUNET_SCHEDULER_add_now (sched,
-                               &schedule_next_hello,
+    = GNUNET_SCHEDULER_add_now (&schedule_next_hello,
                                pl);
   return want;
 }
@@ -1301,12 +1281,14 @@ hello_advertising_ready (void *cls,
 /**
  * Last task run during shutdown.  Disconnects us from
  * the transport and core.
+ *
+ * @param cls unused, NULL
+ * @param tc scheduler context
  */
 static void
-cleaning_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+cleaning_task (void *cls, 
+              const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  struct DisconnectList *dl;
-
   if (NULL != peerinfo_notify)
     {
       GNUNET_PEERINFO_notify_cancel (peerinfo_notify);
@@ -1314,21 +1296,16 @@ cleaning_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
     }
   GNUNET_TRANSPORT_disconnect (transport);
   transport = NULL;
-  while (NULL != peers)
-    free_peer (peers);     
+  GNUNET_CONTAINER_multihashmap_iterate (peers,
+                                        &free_peer,
+                                        NULL);
+  GNUNET_CONTAINER_multihashmap_destroy (peers);
   if (handle != NULL)
     {
       GNUNET_CORE_disconnect (handle);
       handle = NULL;
     }
-  while (NULL != (dl = disconnect_head))
-    {
-      GNUNET_CONTAINER_DLL_remove (disconnect_head,
-                                  disconnect_tail,
-                                  dl);
-      GNUNET_TRANSPORT_blacklist_cancel (dl->rh);
-      GNUNET_free (dl);
-    }
+  whitelist_peers ();
   if (stats != NULL)
     {
       GNUNET_STATISTICS_destroy (stats, GNUNET_NO);
@@ -1341,14 +1318,12 @@ cleaning_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
  * Main function that will be run.
  *
  * @param cls closure
- * @param s the scheduler to use
  * @param args remaining command-line arguments
  * @param cfgfile name of the configuration file used (for saving, can be NULL!)
  * @param c configuration
  */
 static void
 run (void *cls,
-     struct GNUNET_SCHEDULER_Handle * s,
      char *const *args,
      const char *cfgfile,
      const struct GNUNET_CONFIGURATION_Handle * c)
@@ -1360,9 +1335,8 @@ run (void *cls,
     };
   unsigned long long opt;
 
-  sched = s;
   cfg = c;
-  stats = GNUNET_STATISTICS_create (sched, "topology", cfg);
+  stats = GNUNET_STATISTICS_create ("topology", cfg);
   autoconnect = GNUNET_CONFIGURATION_get_value_yesno (cfg,
                                                      "TOPOLOGY",
                                                      "AUTOCONNECT");
@@ -1383,6 +1357,7 @@ run (void *cls,
                                             &opt))
     opt = 16;
   target_connection_count = (unsigned int) opt;
+  peers = GNUNET_CONTAINER_multihashmap_create (target_connection_count * 2);
 
   if ( (friends_only == GNUNET_YES) ||
        (minimum_friend_count > 0) )
@@ -1394,32 +1369,33 @@ run (void *cls,
              minimum_friend_count,
              autoconnect ? "autoconnect enabled" : "autoconnect disabled");
 #endif       
-  transport = GNUNET_TRANSPORT_connect (sched,
-                                       cfg,
+  if (friend_count < minimum_friend_count) 
+    blacklist = GNUNET_TRANSPORT_blacklist (cfg,
+                                           &blacklist_check, NULL);
+  transport = GNUNET_TRANSPORT_connect (cfg,
+                                       NULL,
                                        NULL,
                                        NULL,
                                        NULL,
                                        NULL);
-  handle = GNUNET_CORE_connect (sched,
-                               cfg,
-                               GNUNET_TIME_UNIT_FOREVER_REL,
+  handle = GNUNET_CORE_connect (cfg,
+                               1,
                                NULL,
                                &core_init,
-                               NULL,
                                &connect_notify,
-                               &disconnect_notify,
+                               &disconnect_notify, 
+                               NULL,
                                NULL, GNUNET_NO,
                                NULL, GNUNET_NO,
                                handlers);
-  GNUNET_SCHEDULER_add_delayed (sched,
-                                GNUNET_TIME_UNIT_FOREVER_REL,
+  GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
                                 &cleaning_task, NULL);
   if (NULL == transport)
     {
       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                  _("Failed to connect to `%s' service.\n"),
                  "transport");
-      GNUNET_SCHEDULER_shutdown (sched);
+      GNUNET_SCHEDULER_shutdown ();
       return;
     }
   if (NULL == handle)
@@ -1427,20 +1403,12 @@ run (void *cls,
       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                  _("Failed to connect to `%s' service.\n"),
                  "core");
-      GNUNET_SCHEDULER_shutdown (sched);
+      GNUNET_SCHEDULER_shutdown ();
       return;
     }
 }
 
 
-/**
- * gnunet-daemon-topology command line options.
- */
-static struct GNUNET_GETOPT_CommandLineOption options[] = {
-  GNUNET_GETOPT_OPTION_END
-};
-
-
 /**
  * The main function for the topology daemon.
  *
@@ -1451,6 +1419,9 @@ static struct GNUNET_GETOPT_CommandLineOption options[] = {
 int
 main (int argc, char *const *argv)
 {
+  static const struct GNUNET_GETOPT_CommandLineOption options[] = {
+    GNUNET_GETOPT_OPTION_END
+  };
   int ret;
 
   ret = (GNUNET_OK ==