fix compiler warning for format string
[oweals/gnunet.git] / src / gns / gnunet-service-gns.c
index 822cc7d12c4e2adf72aed7e06f2d2d7defa733a3..3e718dac851831fced2178b0e9ef4040020319d1 100644 (file)
@@ -1,6 +1,6 @@
 /*
      This file is part of GNUnet.
-     (C) 2009, 2010, 2011, 2012 Christian Grothoff (and other contributing authors)
+     Copyright (C) 2011-2013 GNUnet e.V.
 
      GNUnet is free software; you can redistribute it and/or modify
      it under the terms of the GNU General Public License as published
 
      You should have received a copy of the GNU General Public License
      along with GNUnet; see the file COPYING.  If not, write to the
-     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-     Boston, MA 02111-1307, USA.
+     Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+     Boston, MA 02110-1301, USA.
 */
 /**
  * @file gns/gnunet-service-gns.c
- * @brief GNUnet GNS service
+ * @brief GNU Name System (main service)
  * @author Martin Schanzenbach
+ * @author Christian Grothoff
  */
 #include "platform.h"
 #include "gnunet_util_lib.h"
-#include "gnunet_transport_service.h"
 #include "gnunet_dns_service.h"
 #include "gnunet_dnsparser_lib.h"
 #include "gnunet_dht_service.h"
+#include "gnunet_namecache_service.h"
 #include "gnunet_namestore_service.h"
+#include "gnunet_identity_service.h"
 #include "gnunet_gns_service.h"
 #include "gnunet_statistics_service.h"
 #include "gns.h"
-#include "gns_common.h"
 #include "gnunet-service-gns_resolver.h"
+#include "gnunet-service-gns_reverser.h"
+#include "gnunet-service-gns_shorten.h"
 #include "gnunet-service-gns_interceptor.h"
 #include "gnunet_protocols.h"
 
 #define INITIAL_PUT_INTERVAL GNUNET_TIME_UNIT_MILLISECONDS
 
 /**
- * The upper bound for the zone iteration interval in milliseconds
+ * The lower bound for the zone iteration interval
  */
 #define MINIMUM_ZONE_ITERATION_INTERVAL GNUNET_TIME_UNIT_SECONDS
 
+/**
+ * The upper bound for the zone iteration interval
+ */
+#define MAXIMUM_ZONE_ITERATION_INTERVAL GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 15)
+
 /**
  * The default put interval for the zone iteration. In case
- * No option is found
+ * no option is found
  */
 #define DEFAULT_ZONE_PUBLISH_TIME_WINDOW GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 4)
 
  */
 #define LATE_ITERATION_SPEEDUP_FACTOR 2
 
+/**
+ * How long until a DHT PUT attempt should time out?
+ */
+#define DHT_OPERATION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 60)
+
+/**
+ * What replication level do we use for DHT PUT operations?
+ */
+#define DHT_GNS_REPLICATION_LEVEL 5
+
+/**
+ * GnsClient prototype
+ */
+struct GnsClient;
 
 /**
  * Handle to a lookup operation from api
@@ -68,39 +90,80 @@ struct ClientLookupHandle
 {
 
   /**
-   * Handle to the requesting client
+   * We keep these in a DLL.
    */
-  struct GNUNET_SERVER_Client *client;
+  struct ClientLookupHandle *next;
 
   /**
-   * optional zone private key used for shorten
+   * We keep these in a DLL.
+   */
+  struct ClientLookupHandle *prev;
+  
+  /**
+   * Client handle
    */
-  struct GNUNET_CRYPTO_EccPrivateKey *shorten_key;
+  struct GnsClient *gc;
 
   /**
-   * the name to look up
+   * Active handle for the lookup.
    */
-  char *name; 
+  struct GNS_ResolverHandle *lookup;
 
   /**
-   * The zone we look up in
+   * Active handle for a reverse lookup
    */
-  struct GNUNET_CRYPTO_ShortHashCode zone;
+  struct GNS_ReverserHandle *rev_lookup;
 
   /**
-   * request id 
+   * request id
    */
   uint32_t request_id;
 
+};
+
+struct GnsClient
+{
+  /**
+   * The client
+   */
+  struct GNUNET_SERVICE_Client *client;
+
   /**
-   * GNUNET_YES if we only want to lookup from local cache
+   * The MQ
    */
-  int only_cached;
+  struct GNUNET_MQ_Handle *mq;
 
   /**
-   * request type
+   * Head of the DLL.
    */
-  int type;
+  struct ClientLookupHandle *clh_head;
+
+  /**
+   * Tail of the DLL.
+   */
+  struct ClientLookupHandle *clh_tail;
+};
+
+
+/**
+ * Handle for DHT PUT activity triggered from the namestore monitor.
+ */
+struct MonitorActivity
+{
+  /**
+   * Kept in a DLL.
+   */
+  struct MonitorActivity *next;
+
+  /**
+   * Kept in a DLL.
+   */
+  struct MonitorActivity *prev;
+
+  /**
+   * Handle for the DHT PUT operation.
+   */
+  struct GNUNET_DHT_PutHandle *ph;
 };
 
 
@@ -110,29 +173,50 @@ struct ClientLookupHandle
 static struct GNUNET_DHT_Handle *dht_handle;
 
 /**
- * Our zone's private key
+ * Active DHT put operation (or NULL)
  */
-static struct GNUNET_CRYPTO_EccPrivateKey *zone_key;
+static struct GNUNET_DHT_PutHandle *active_put;
 
 /**
  * Our handle to the namestore service
  */
 static struct GNUNET_NAMESTORE_Handle *namestore_handle;
 
+/**
+ * Our handle to the namecache service
+ */
+static struct GNUNET_NAMECACHE_Handle *namecache_handle;
+
+/**
+ * Our handle to the identity service
+ */
+static struct GNUNET_IDENTITY_Handle *identity_handle;
+
+/**
+ * Our handle to the identity operation to find the master zone
+ * for intercepted queries.
+ */
+static struct GNUNET_IDENTITY_Operation *identity_op;
+
 /**
  * Handle to iterate over our authoritative zone in namestore
  */
 static struct GNUNET_NAMESTORE_ZoneIterator *namestore_iter;
 
 /**
- * Our notification context.
+ * Handle to monitor namestore changes to instant propagation.
+ */
+static struct GNUNET_NAMESTORE_ZoneMonitor *zmon;
+
+/**
+ * Head of monitor activities; kept in a DLL.
  */
-static struct GNUNET_SERVER_NotificationContext *nc;
+static struct MonitorActivity *ma_head;
 
 /**
- * Our zone hash
+ * Tail of monitor activities; kept in a DLL.
  */
-static struct GNUNET_CRYPTO_ShortHashCode zone_hash;
+static struct MonitorActivity *ma_tail;
 
 /**
  * Useful for zone update for DHT put
@@ -145,43 +229,44 @@ static unsigned long long num_public_records;
 static unsigned long long last_num_public_records;
 
 /**
- * Zone iteration PUT interval.
+ * Minimum relative expiration time of records seem during the current
+ * zone iteration.
  */
-static struct GNUNET_TIME_Relative put_interval;
+static struct GNUNET_TIME_Relative min_relative_record_time;
 
 /**
- * Time window for zone iteration
+ * Zone iteration PUT interval.
  */
-static struct GNUNET_TIME_Relative zone_publish_time_window;
+static struct GNUNET_TIME_Relative put_interval;
 
 /**
- * zone publish task
+ * Default time window for zone iteration
  */
-static GNUNET_SCHEDULER_TaskIdentifier zone_publish_task;
+static struct GNUNET_TIME_Relative zone_publish_time_window_default;
 
 /**
- * GNUNET_YES if automatic pkey import for name shortening
- * is enabled
+ * Time window for zone iteration, adjusted based on relative record
+ * expiration times in our zone.
  */
-static int auto_import_pkey;
+static struct GNUNET_TIME_Relative zone_publish_time_window;
 
 /**
- * GNUNET_YES if zone has never been published before
+ * zone publish task
  */
-static int first_zone_iteration;
+static struct GNUNET_SCHEDULER_Task *zone_publish_task;
 
 /**
- * The lookup timeout
+ * #GNUNET_YES if zone has never been published before
  */
-static struct GNUNET_TIME_Relative default_lookup_timeout;
+static int first_zone_iteration;
 
 /**
- * GNUNET_YES if ipv6 is supported
+ * #GNUNET_YES if ipv6 is supported
  */
 static int v6_enabled;
 
 /**
- * GNUNET_YES if ipv4 is supported
+ * #GNUNET_YES if ipv4 is supported
  */
 static int v4_enabled;
 
@@ -198,35 +283,70 @@ static struct GNUNET_STATISTICS_Handle *statistics;
  * @param tc unused
  */
 static void
-shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+shutdown_task (void *cls)
 {
-  struct ClientShortenHandle *csh_tmp;
+  struct MonitorActivity *ma;
 
-  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
-             "Shutting down!\n");
-  GNUNET_SERVER_notification_context_destroy (nc);  
-  gns_interceptor_stop ();
-  gns_resolver_cleanup ();
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Shutting down!\n");
+  GNS_interceptor_done ();
+  if (NULL != identity_op)
+  {
+    GNUNET_IDENTITY_cancel (identity_op);
+    identity_op = NULL;
+  }
+  if (NULL != identity_handle)
+  {
+    GNUNET_IDENTITY_disconnect (identity_handle);
+    identity_handle = NULL;
+  }
+  GNS_resolver_done ();
+  GNS_reverse_done ();
+  GNS_shorten_done ();
+  while (NULL != (ma = ma_head))
+  {
+    GNUNET_DHT_put_cancel (ma->ph);
+    GNUNET_CONTAINER_DLL_remove (ma_head,
+                                 ma_tail,
+                                 ma);
+    GNUNET_free (ma);
+  }
   if (NULL != statistics)
   {
-    GNUNET_STATISTICS_destroy (statistics, GNUNET_NO);
+    GNUNET_STATISTICS_destroy (statistics,
+                               GNUNET_NO);
     statistics = NULL;
   }
-  if (GNUNET_SCHEDULER_NO_TASK != zone_publish_task)
+  if (NULL != zone_publish_task)
   {
     GNUNET_SCHEDULER_cancel (zone_publish_task);
-    zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
+    zone_publish_task = NULL;
   }
   if (NULL != namestore_iter)
   {
     GNUNET_NAMESTORE_zone_iteration_stop (namestore_iter);
     namestore_iter = NULL;
   }
+  if (NULL != zmon)
+  {
+    GNUNET_NAMESTORE_zone_monitor_stop (zmon);
+    zmon = NULL;
+  }
   if (NULL != namestore_handle)
   {
     GNUNET_NAMESTORE_disconnect (namestore_handle);
     namestore_handle = NULL;
   }
+  if (NULL != namecache_handle)
+  {
+    GNUNET_NAMECACHE_disconnect (namecache_handle);
+    namecache_handle = NULL;
+  }
+  if (NULL != active_put)
+  {
+    GNUNET_DHT_put_cancel (active_put);
+    active_put = NULL;
+  }
   if (NULL != dht_handle)
   {
     GNUNET_DHT_disconnect (dht_handle);
@@ -234,18 +354,74 @@ shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   }
 }
 
+/**
+ * Called whenever a client is disconnected.
+ *
+ * @param cls closure
+ * @param client identification of the client
+ * @param app_ctx @a client
+ */
+static void
+client_disconnect_cb (void *cls,
+                      struct GNUNET_SERVICE_Client *client,
+                      void *app_ctx)
+{
+  struct ClientLookupHandle *clh;
+  struct GnsClient *gc = app_ctx;
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Client %p disconnected\n",
+              client);
+  while (NULL != (clh = gc->clh_head))
+  {
+    if (NULL != clh->lookup)
+      GNS_resolver_lookup_cancel (clh->lookup);
+    if (NULL != clh->rev_lookup)
+      GNS_reverse_lookup_cancel (clh->rev_lookup);
+    GNUNET_CONTAINER_DLL_remove (gc->clh_head,
+                                 gc->clh_tail,
+                                 clh);
+    GNUNET_free (clh);
+  }
+
+  GNUNET_free (gc); 
+}
+
+
+/**
+ * Add a client to our list of active clients.
+ *
+ * @param cls NULL
+ * @param client client to add
+ * @param mq message queue for @a client
+ * @return internal namestore client structure for this client
+ */
+static void *
+client_connect_cb (void *cls,
+                   struct GNUNET_SERVICE_Client *client,
+                   struct GNUNET_MQ_Handle *mq)
+{
+  struct GnsClient *gc;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Client %p connected\n",
+              client);
+  gc = GNUNET_new (struct GnsClient);
+  gc->client = client;
+  gc->mq = mq;
+  return gc;
+}
+
 
 /**
  * Method called periodically that triggers iteration over authoritative records
  *
  * @param cls closure
- * @param tc task context
  */
 static void
-publish_zone_dht_next (void *cls,
-                       const struct GNUNET_SCHEDULER_TaskContext *tc)
+publish_zone_dht_next (void *cls)
 {
-  zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
+  zone_publish_task = NULL;
+  GNUNET_assert (NULL != namestore_iter);
   GNUNET_NAMESTORE_zone_iterator_next (namestore_iter);
 }
 
@@ -254,219 +430,384 @@ publish_zone_dht_next (void *cls,
  * Periodically iterate over our zone and store everything in dht
  *
  * @param cls NULL
- * @param tc task context
  */
 static void
-publish_zone_dht_start (void *cls, 
-                       const struct GNUNET_SCHEDULER_TaskContext *tc);
+publish_zone_dht_start (void *cls);
 
 
 /**
- * Function used to put all records successively into the DHT.
+ * Continuation called from DHT once the PUT operation is done.
  *
- * @param cls the closure (NULL)
- * @param key the public key of the authority (ours)
- * @param expiration lifetime of the namestore entry
- * @param name the name of the records
- * @param rd_count the number of records in data
- * @param rd the record data
- * @param signature the signature for the record data
+ * @param cls closure, NULL if called from regular iteration,
+ *        `struct MonitorActivity` if called from #handle_monitor_event.
+ * @param success #GNUNET_OK on success
  */
 static void
-put_gns_record (void *cls,
-                const struct GNUNET_CRYPTO_EccPublicKey *key,
-                struct GNUNET_TIME_Absolute expiration,
-                const char *name,
-                unsigned int rd_count,
-                const struct GNUNET_NAMESTORE_RecordData *rd,
-                const struct GNUNET_CRYPTO_EccSignature *signature)
-{  
-  struct GNSNameRecordBlock *nrb;
-  struct GNUNET_CRYPTO_ShortHashCode zhash;
-  struct GNUNET_HashCode dht_key;
-  uint32_t rd_payload_length;
-  char* nrb_data = NULL;
-  size_t namelen;
-  struct GNUNET_TIME_Relative next_put_interval; 
+dht_put_continuation (void *cls,
+                      int success)
+{
+  struct MonitorActivity *ma = cls;
+  struct GNUNET_TIME_Relative next_put_interval;
 
-  if (NULL == name)
+  num_public_records++;
+  if (NULL == ma)
   {
-    /* we're done */
-    namestore_iter = NULL;
-    last_num_public_records = num_public_records;
-    first_zone_iteration = GNUNET_NO;
-    if (0 == num_public_records)
-    {
-      /**
-       * If no records are known (startup) or none present
-       * we can safely set the interval to the value for a single
-       * record
-       */
-      put_interval = zone_publish_time_window;
-      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
-                 "No records in db.\n");
-    }
-    else
+    active_put = NULL;
+    if ( (num_public_records > last_num_public_records) &&
+         (GNUNET_NO == first_zone_iteration) )
     {
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                  "Last record count was lower than current record count.  Reducing interval.\n");
       put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
-                                                 num_public_records);
+                                                  num_public_records);
+      next_put_interval = GNUNET_TIME_relative_divide (put_interval,
+                                                       LATE_ITERATION_SPEEDUP_FACTOR);
     }
-    put_interval = GNUNET_TIME_relative_max (MINIMUM_ZONE_ITERATION_INTERVAL,
-                                            put_interval);
-
+    else
+      next_put_interval = put_interval;
+    next_put_interval = GNUNET_TIME_relative_min (next_put_interval,
+                                                  MAXIMUM_ZONE_ITERATION_INTERVAL);
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-               "Zone iteration finished. Adjusted zone iteration interval to %s\n",
-               GNUNET_STRINGS_relative_time_to_string (put_interval, GNUNET_YES));
-    GNUNET_STATISTICS_set (statistics,
-                           "Current zone iteration interval (in ms)",
-                           put_interval.rel_value_us / 1000LL,
-                           GNUNET_NO);
-    GNUNET_STATISTICS_update (statistics,
-                              "Number of zone iterations", 1, GNUNET_NO);
+                "PUT complete, next PUT in %s!\n",
+                GNUNET_STRINGS_relative_time_to_string (next_put_interval,
+                                                        GNUNET_YES));
+
     GNUNET_STATISTICS_set (statistics,
-                           "Number of public records in DHT",
-                           last_num_public_records,
+                           "Current zone iteration interval (ms)",
+                           next_put_interval.rel_value_us / 1000LL,
                            GNUNET_NO);
-    if (0 == num_public_records)
-      zone_publish_task = GNUNET_SCHEDULER_add_delayed (put_interval,
-                                                         &publish_zone_dht_start,
-                                                         NULL);
-    else
-      zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start, NULL);
-    return;
+    GNUNET_assert (NULL == zone_publish_task);
+    zone_publish_task = GNUNET_SCHEDULER_add_delayed (next_put_interval,
+                                                      &publish_zone_dht_next,
+                                                      NULL);
   }
-  
-  namelen = strlen (name) + 1;
-  if (0 == rd_count)
+  else
   {
-    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-               "No records for name `%s'! Skipping.\n",
-               name);
-    zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_next,
-                                                   NULL);
-    return;
+    GNUNET_CONTAINER_DLL_remove (ma_head,
+                                 ma_tail,
+                                 ma);
+    GNUNET_free (ma);
   }
-  if (NULL == signature)
+}
+
+
+/**
+ * Convert namestore records from the internal format to that
+ * suitable for publication (removes private records, converts
+ * to absolute expiration time).
+ *
+ * @param rd input records
+ * @param rd_count size of the @a rd and @a rd_public arrays
+ * @param rd_public where to write the converted records
+ * @return number of records written to @a rd_public
+ */
+static unsigned int
+convert_records_for_export (const struct GNUNET_GNSRECORD_Data *rd,
+                            unsigned int rd_count,
+                            struct GNUNET_GNSRECORD_Data *rd_public)
+{
+  struct GNUNET_TIME_Absolute now;
+  unsigned int rd_public_count;
+  unsigned int i;
+
+  rd_public_count = 0;
+  now = GNUNET_TIME_absolute_get ();
+  for (i=0;i<rd_count;i++)
+    if (0 == (rd[i].flags & GNUNET_GNSRECORD_RF_PRIVATE))
+    {
+      rd_public[rd_public_count] = rd[i];
+      if (0 != (rd[i].flags & GNUNET_GNSRECORD_RF_RELATIVE_EXPIRATION))
+      {
+        /* GNUNET_GNSRECORD_block_create will convert to absolute time;
+           we just need to adjust our iteration frequency */
+        min_relative_record_time.rel_value_us =
+          GNUNET_MIN (rd_public[rd_public_count].expiration_time,
+                      min_relative_record_time.rel_value_us);
+      }
+      else if (rd_public[rd_public_count].expiration_time < now.abs_value_us)
+      {
+        /* record already expired, skip it */
+        continue;
+      }
+      rd_public_count++;
+    }
+  return rd_public_count;
+}
+
+
+/**
+ * Store GNS records in the DHT.
+ *
+ * @param key key of the zone
+ * @param label label to store under
+ * @param rd_public public record data
+ * @param rd_public_count number of records in @a rd_public
+ * @param pc_arg closure argument to pass to the #dht_put_continuation
+ * @return DHT PUT handle, NULL on error
+ */
+static struct GNUNET_DHT_PutHandle *
+perform_dht_put (const struct GNUNET_CRYPTO_EcdsaPrivateKey *key,
+                 const char *label,
+                 const struct GNUNET_GNSRECORD_Data *rd_public,
+                 unsigned int rd_public_count,
+                 void *pc_arg)
+{
+  struct GNUNET_GNSRECORD_Block *block;
+  struct GNUNET_HashCode query;
+  struct GNUNET_TIME_Absolute expire;
+  size_t block_size;
+  struct GNUNET_DHT_PutHandle *ret;
+
+  expire = GNUNET_GNSRECORD_record_get_expiration_time (rd_public_count,
+                                                        rd_public);
+  block = GNUNET_GNSRECORD_block_create (key,
+                                         expire,
+                                         label,
+                                         rd_public,
+                                         rd_public_count);
+  if (NULL == block)
+    return NULL; /* whoops */
+  block_size = ntohl (block->purpose.size)
+    + sizeof (struct GNUNET_CRYPTO_EcdsaSignature)
+    + sizeof (struct GNUNET_CRYPTO_EcdsaPublicKey);
+  GNUNET_GNSRECORD_query_from_private_key (key,
+                                           label,
+                                           &query);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Storing %u record(s) for label `%s' in DHT with expiration `%s' under key %s\n",
+              rd_public_count,
+              label,
+              GNUNET_STRINGS_absolute_time_to_string (expire),
+              GNUNET_h2s (&query));
+  ret = GNUNET_DHT_put (dht_handle,
+                        &query,
+                        DHT_GNS_REPLICATION_LEVEL,
+                        GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE,
+                        GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
+                        block_size,
+                        block,
+                        expire,
+                        &dht_put_continuation,
+                        pc_arg);
+  GNUNET_free (block);
+  return ret;
+}
+
+
+/**
+ * We encountered an error in our zone iteration.
+ */
+static void
+zone_iteration_error (void *cls)
+{
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Got disconnected from namestore database, retrying.\n");
+  namestore_iter = NULL;
+  /* We end up here on error/disconnect/shutdown, so potentially
+     while a zone publish task or a DHT put is still running; hence
+     we need to cancel those. */
+  if (NULL != zone_publish_task)
   {
-    GNUNET_break (0);
-    zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_next,
-                                                   NULL);
-    return;
+    GNUNET_SCHEDULER_cancel (zone_publish_task);
+    zone_publish_task = NULL;
   }
-  
-  /* TODO 2) AB: New publishing
-   *
-   * - Use new signature S_d
-   * - Obtain new derived public key V = H(H(i,Q) * Q)
-   * - Obtain HKDF(i,Q)
-   * - Compute encrypte record block E with HKDF(i,Q) (rd, rd_count)
-   * - Create block B = |V,E,S_d|
-   * - Compute new DHT key H(V) in TODO 3)
-   *
-   * -> Put (H(V), B)
-   */
+  if (NULL != active_put)
+  {
+    GNUNET_DHT_put_cancel (active_put);
+    active_put = NULL;
+  }
+  zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
+                                                NULL);
+}
+
+
+/**
+ * Zone iteration is completed.
+ */
+static void
+zone_iteration_finished (void *cls)
+{
+  /* we're done with one iteration, calculate when to do the next one */
+  namestore_iter = NULL;
+  last_num_public_records = num_public_records;
+  first_zone_iteration = GNUNET_NO;
+  if (0 == num_public_records)
+  {
+    /**
+     * If no records are known (startup) or none present
+     * we can safely set the interval to the value for a single
+     * record
+     */
+    put_interval = zone_publish_time_window;
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
+                "No records in namestore database.\n");
+  }
+  else
+  {
+    /* If records are present, next publication is based on the minimum
+     * relative expiration time of the records published divided by 4
+     */
+    zone_publish_time_window
+      = GNUNET_TIME_relative_min (GNUNET_TIME_relative_divide (min_relative_record_time, 4),
+                                  zone_publish_time_window_default);
+    put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
+                                                num_public_records);
+  }
+  /* reset for next iteration */
+  min_relative_record_time = GNUNET_TIME_UNIT_FOREVER_REL;
+  put_interval = GNUNET_TIME_relative_max (MINIMUM_ZONE_ITERATION_INTERVAL,
+                                           put_interval);
+  put_interval = GNUNET_TIME_relative_min (put_interval,
+                                           MAXIMUM_ZONE_ITERATION_INTERVAL);
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-             "Putting records for `%s' into the DHT\n", name); 
-  rd_payload_length = GNUNET_NAMESTORE_records_get_size (rd_count, rd); 
-  nrb = GNUNET_malloc (rd_payload_length + namelen
-                      + sizeof (struct GNSNameRecordBlock));
-  nrb->signature = *signature;
-  nrb->public_key = *key;
-  nrb->rd_count = htonl (rd_count);
-  memcpy (&nrb[1], name, namelen);
-  nrb_data = (char *) &nrb[1];
-  nrb_data += namelen;
-  rd_payload_length += sizeof(struct GNSNameRecordBlock) + namelen;
-  GNUNET_CRYPTO_short_hash (key,
-                           sizeof (struct GNUNET_CRYPTO_EccPublicKey),
-                           &zhash);
-  if (-1 == GNUNET_NAMESTORE_records_serialize (rd_count,
-                                                rd,
-                                                rd_payload_length,
-                                                nrb_data))
+              "Zone iteration finished. Adjusted zone iteration interval to %s\n",
+              GNUNET_STRINGS_relative_time_to_string (put_interval,
+                                                      GNUNET_YES));
+  GNUNET_STATISTICS_set (statistics,
+                         "Current zone iteration interval (in ms)",
+                         put_interval.rel_value_us / 1000LL,
+                         GNUNET_NO);
+  GNUNET_STATISTICS_update (statistics,
+                            "Number of zone iterations",
+                            1,
+                            GNUNET_NO);
+  GNUNET_STATISTICS_set (statistics,
+                         "Number of public records in DHT",
+                         last_num_public_records,
+                         GNUNET_NO);
+  GNUNET_assert (NULL == zone_publish_task);
+  if (0 == num_public_records)
+    zone_publish_task = GNUNET_SCHEDULER_add_delayed (put_interval,
+                                                      &publish_zone_dht_start,
+                                                      NULL);
+  else
+    zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
+                                                  NULL);
+}
+
+
+/**
+ * Function used to put all records successively into the DHT.
+ *
+ * @param cls the closure (NULL)
+ * @param key the private key of the authority (ours)
+ * @param label the name of the records, NULL once the iteration is done
+ * @param rd_count the number of records in @a rd
+ * @param rd the record data
+ */
+static void
+put_gns_record (void *cls,
+                const struct GNUNET_CRYPTO_EcdsaPrivateKey *key,
+                const char *label,
+                unsigned int rd_count,
+                const struct GNUNET_GNSRECORD_Data *rd)
+{
+  struct GNUNET_GNSRECORD_Data rd_public[rd_count];
+  unsigned int rd_public_count;
+
+  rd_public_count = convert_records_for_export (rd,
+                                                rd_count,
+                                                rd_public);
+
+  if (0 == rd_public_count)
   {
-    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-               _("Records for name `%s' in zone %s too large to fit into DHT"),
-               name,
-               GNUNET_short_h2s (&zhash));
-    GNUNET_free (nrb);
+    GNUNET_assert (NULL == zone_publish_task);
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "Record set empty, moving to next record set\n");
     zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_next,
-                                                   NULL);
+                                                  NULL);
     return;
   }
-  /* TODO AB: Here records are put in the DHT: modify dht_key to H(key) = H(H(name,zone) * zone) */
-  GNUNET_GNS_get_key_for_record (name, &zhash, &dht_key);
+  /* We got a set of records to publish */
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-             "putting %u records from zone %s for `%s' under key: %s with size %u and timeout %s\n",
-             rd_count,
-             GNUNET_short_h2s (&zhash),
-             name, 
-             GNUNET_h2s (&dht_key), 
-             (unsigned int) rd_payload_length,
-             GNUNET_STRINGS_relative_time_to_string (DHT_OPERATION_TIMEOUT, GNUNET_YES));
-  
-  GNUNET_STATISTICS_update (statistics,
-                            "Record bytes put into DHT", 
-                           rd_payload_length, GNUNET_NO);
-
-  (void) GNUNET_DHT_put (dht_handle, &dht_key,
-                        DHT_GNS_REPLICATION_LEVEL,
-                        GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE,
-                        GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
-                        rd_payload_length,
-                        (char*)nrb,
-                        expiration,
-                        DHT_OPERATION_TIMEOUT,
-                        NULL,
-                        NULL); 
-  GNUNET_free (nrb);
-
-  num_public_records++;  
-  if ( (num_public_records > last_num_public_records)
-       && (GNUNET_NO == first_zone_iteration) )
+              "Starting DHT PUT\n");
+  active_put = perform_dht_put (key,
+                                label,
+                                rd_public,
+                                rd_public_count,
+                                NULL);
+  if (NULL == active_put)
   {
-    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-               "Last record count was lower than current record count.  Reducing interval.\n");
-    put_interval = GNUNET_TIME_relative_divide (zone_publish_time_window,
-                                               num_public_records);
-    next_put_interval = GNUNET_TIME_relative_divide (put_interval,
-                                                    LATE_ITERATION_SPEEDUP_FACTOR);
+    GNUNET_break (0);
+    dht_put_continuation (NULL, GNUNET_NO);
   }
-  else
-    next_put_interval = put_interval;
-
-  GNUNET_STATISTICS_set (statistics,
-                        "Current zone iteration interval (ms)",
-                        next_put_interval.rel_value_us / 1000LL,
-                        GNUNET_NO); 
-  zone_publish_task = GNUNET_SCHEDULER_add_delayed (next_put_interval,
-                                                   &publish_zone_dht_next,
-                                                   NULL);
 }
 
 
 /**
- * Periodically iterate over our zone and store everything in dht
+ * Periodically iterate over all zones and store everything in DHT
  *
  * @param cls NULL
- * @param tc task context
  */
 static void
-publish_zone_dht_start (void *cls, 
-                       const struct GNUNET_SCHEDULER_TaskContext *tc)
+publish_zone_dht_start (void *cls)
 {
-  zone_publish_task = GNUNET_SCHEDULER_NO_TASK;
+  zone_publish_task = NULL;
 
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, 
-             "Scheduling DHT zone update!\n");  
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Starting DHT zone update!\n");
   /* start counting again */
   num_public_records = 0;
-  namestore_iter = GNUNET_NAMESTORE_zone_iteration_start (namestore_handle,
-                                                         NULL, /* All zones */
-                                                         GNUNET_NAMESTORE_RF_AUTHORITY,
-                                                         GNUNET_NAMESTORE_RF_PRIVATE,
-                                                         &put_gns_record,
-                                                         NULL);
+  GNUNET_assert (NULL == namestore_iter);
+  namestore_iter
+    = GNUNET_NAMESTORE_zone_iteration_start (namestore_handle,
+                                             NULL, /* All zones */
+                                             &zone_iteration_error,
+                                             NULL,
+                                             &put_gns_record,
+                                             NULL,
+                                             &zone_iteration_finished,
+                                             NULL);
+}
+
+
+/**
+ * Process a record that was stored in the namestore
+ * (invoked by the monitor).
+ *
+ * @param cls closure, NULL
+ * @param zone private key of the zone; NULL on disconnect
+ * @param label label of the records; NULL on disconnect
+ * @param rd_count number of entries in @a rd array, 0 if label was deleted
+ * @param rd array of records with data to store
+ */
+static void
+handle_monitor_event (void *cls,
+                      const struct GNUNET_CRYPTO_EcdsaPrivateKey *zone,
+                      const char *label,
+                      unsigned int rd_count,
+                      const struct GNUNET_GNSRECORD_Data *rd)
+{
+  struct GNUNET_GNSRECORD_Data rd_public[rd_count];
+  unsigned int rd_public_count;
+  struct MonitorActivity *ma;
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Received %u records for label `%s' via namestore monitor\n",
+              rd_count,
+              label);
+  /* filter out records that are not public, and convert to
+     absolute expiration time. */
+  rd_public_count = convert_records_for_export (rd,
+                                                rd_count,
+                                                rd_public);
+  if (0 == rd_public_count)
+    return; /* nothing to do */
+  ma = GNUNET_new (struct MonitorActivity);
+  ma->ph = perform_dht_put (zone,
+                            label,
+                            rd,
+                            rd_count,
+                            ma);
+  if (NULL == ma->ph)
+  {
+    /* PUT failed, do not remember operation */
+    GNUNET_free (ma);
+    return;
+  }
+  GNUNET_CONTAINER_DLL_insert (ma_head,
+                               ma_tail,
+                               ma);
 }
 
 
@@ -477,51 +818,116 @@ publish_zone_dht_start (void *cls,
  * Reply to client with the result from our lookup.
  *
  * @param cls the closure (our client lookup handle)
- * @param rd_count the number of records
+ * @param rd_count the number of records in @a rd
  * @param rd the record data
  */
 static void
 send_lookup_response (void* cls,
-                     uint32_t rd_count,
-                     const struct GNUNET_NAMESTORE_RecordData *rd)
+                      uint32_t rd_count,
+                      const struct GNUNET_GNSRECORD_Data *rd)
 {
-  struct ClientLookupHandle* clh = cls;
-  struct GNUNET_GNS_ClientLookupResultMessage *rmsg;
+  struct ClientLookupHandle *clh = cls;
+  struct GNUNET_MQ_Envelope *env;
+  struct LookupResultMessage *rmsg;
   size_t len;
-  
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Sending `%s' message with %d results\n",
-              "LOOKUP_RESULT", rd_count);
-  
-  len = GNUNET_NAMESTORE_records_get_size (rd_count, rd);
-  rmsg = GNUNET_malloc (len + sizeof (struct GNUNET_GNS_ClientLookupResultMessage));
-  
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Sending LOOKUP_RESULT message with %u results\n",
+              (unsigned int) rd_count);
+
+  len = GNUNET_GNSRECORD_records_get_size (rd_count, rd);
+  env = GNUNET_MQ_msg_extra (rmsg,
+                             len,
+                             GNUNET_MESSAGE_TYPE_GNS_LOOKUP_RESULT);
   rmsg->id = clh->request_id;
-  rmsg->rd_count = htonl(rd_count);
-  rmsg->header.type = htons(GNUNET_MESSAGE_TYPE_GNS_LOOKUP_RESULT);
-  rmsg->header.size = 
-    htons(len+sizeof(struct GNUNET_GNS_ClientLookupResultMessage));
-  
-  GNUNET_NAMESTORE_records_serialize (rd_count, rd, len, (char*)&rmsg[1]);
-  
-  GNUNET_SERVER_notification_context_unicast (nc, clh->client,
-                                (const struct GNUNET_MessageHeader *) rmsg,
-                                GNUNET_NO);
-  GNUNET_SERVER_receive_done (clh->client, GNUNET_OK);
-  
-  GNUNET_free(rmsg);
-  GNUNET_free(clh->name);
-  
-  if (NULL != clh->shorten_key)
-    GNUNET_CRYPTO_ecc_key_free (clh->shorten_key);
+  rmsg->rd_count = htonl (rd_count);
+  GNUNET_GNSRECORD_records_serialize (rd_count, rd, len,
+                                      (char*) &rmsg[1]);
+  GNUNET_MQ_send (GNUNET_SERVICE_client_get_mq(clh->gc->client),
+                  env);
+  GNUNET_CONTAINER_DLL_remove (clh->gc->clh_head, clh->gc->clh_tail, clh);
   GNUNET_free (clh);
   GNUNET_STATISTICS_update (statistics,
-                            "Completed lookups", 1, GNUNET_NO);
-  if (NULL != rd)
-    GNUNET_STATISTICS_update (statistics,
-                              "Records resolved", rd_count, GNUNET_NO);
+                            "Completed lookups", 1,
+                            GNUNET_NO);
+  GNUNET_STATISTICS_update (statistics,
+                            "Records resolved",
+                            rd_count,
+                            GNUNET_NO);
+}
+
+/**
+ * Reply to client with the result from our reverse lookup.
+ *
+ * @param cls the closure (our client lookup handle)
+ * @param rd_count the number of records in @a rd
+ * @param rd the record data
+ */
+static void
+send_reverse_lookup_response (void* cls,
+                              const char *name)
+{
+  struct ClientLookupHandle *clh = cls;
+  struct GNUNET_MQ_Envelope *env;
+  struct ReverseLookupResultMessage *rmsg;
+  size_t len;
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Sending LOOKUP_RESULT message with %s\n",
+              name);
+
+  if (NULL == name)
+    len = 1;
+  else
+    len = strlen (name) + 1;
+  env = GNUNET_MQ_msg_extra (rmsg,
+                             len,
+                             GNUNET_MESSAGE_TYPE_GNS_REVERSE_LOOKUP_RESULT);
+  rmsg->id = clh->request_id;
+  if (1 < len)
+    GNUNET_memcpy ((char*) &rmsg[1],
+                   name,
+                   strlen (name));
+  GNUNET_MQ_send (GNUNET_SERVICE_client_get_mq(clh->gc->client),
+                  env);
+  GNUNET_CONTAINER_DLL_remove (clh->gc->clh_head, clh->gc->clh_tail, clh);
+  GNUNET_free (clh);
+  GNUNET_STATISTICS_update (statistics,
+                            "Completed reverse lookups", 1,
+                            GNUNET_NO);
 }
 
 
+/**
+ * Checks a #GNUNET_MESSAGE_TYPE_GNS_LOOKUP message
+ *
+ * @param cls client sending the message
+ * @param l_msg message of type `struct LookupMessage`
+ * @return #GNUNET_OK if @a l_msg is well-formed
+ */
+static int
+check_lookup (void *cls,
+              const struct LookupMessage *l_msg)
+{
+  size_t msg_size;
+  const char* name;
+
+  msg_size = ntohs (l_msg->header.size);
+  if (msg_size < sizeof (struct LookupMessage))
+  {
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  name = (const char *) &l_msg[1];
+  if ( ('\0' != name[msg_size - sizeof (struct LookupMessage) - 1]) ||
+       (strlen (name) > GNUNET_DNSPARSER_MAX_NAME_LENGTH) )
+  {
+    GNUNET_break (0);
+    return GNUNET_SYSERR;
+  }
+  return GNUNET_OK;
+}
+
 /**
  * Handle lookup requests from client
  *
@@ -531,113 +937,229 @@ send_lookup_response (void* cls,
  */
 static void
 handle_lookup (void *cls,
-              struct GNUNET_SERVER_Client * client,
-              const struct GNUNET_MessageHeader * message)
+               const struct LookupMessage *sh_msg)
 {
-  size_t namelen;
-  char name[GNUNET_DNSPARSER_MAX_NAME_LENGTH];
+  struct GnsClient *gc = cls;
+  char name[GNUNET_DNSPARSER_MAX_NAME_LENGTH + 1];
   struct ClientLookupHandle *clh;
-  charnameptr = name;
+  char *nameptr = name;
   const char *utf_in;
-  int only_cached;
-  const struct GNUNET_CRYPTO_EccPrivateKey *key;
-  uint16_t msg_size;
-  const struct GNUNET_GNS_ClientLookupMessage *sh_msg;
-  
-  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, 
-             "Received `%s' message\n", "LOOKUP");
-  msg_size = ntohs(message->size);
-  if (msg_size < sizeof (struct GNUNET_GNS_ClientLookupMessage))
-  {
-    GNUNET_break (0);
-    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
-    return;
-  }
-  sh_msg = (const struct GNUNET_GNS_ClientLookupMessage *) message;
-  GNUNET_SERVER_notification_context_add (nc, client);
-  if (GNUNET_YES == ntohl (sh_msg->have_key))
-  {
+  const struct GNUNET_CRYPTO_EcdsaPrivateKey *key;
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Received LOOKUP message\n");
+  GNUNET_SERVICE_client_continue (gc->client);
+  if (GNUNET_YES == ntohs (sh_msg->have_key))
     key = &sh_msg->shorten_key;
-  }
   else
-  {
     key = NULL;
-  }
   utf_in = (const char *) &sh_msg[1];
-  if ('\0' != utf_in[msg_size - sizeof (struct GNUNET_GNS_ClientLookupMessage) - 1])
-  {
-    GNUNET_break (0);
-    GNUNET_SERVER_receive_done (client, GNUNET_SYSERR);
-    return;
-  }  
-  GNUNET_STRINGS_utf8_tolower (utf_in, &nameptr);
-  
-  namelen = strlen (name) + 1;
-  clh = GNUNET_malloc (sizeof (struct ClientLookupHandle));
-  memset (clh, 0, sizeof (struct ClientLookupHandle));
-  clh->client = client;
-  clh->name = GNUNET_malloc (namelen);
-  strcpy (clh->name, name);
+  GNUNET_STRINGS_utf8_tolower (utf_in, nameptr);
+
+  clh = GNUNET_new (struct ClientLookupHandle);
+  GNUNET_CONTAINER_DLL_insert (gc->clh_head, gc->clh_tail, clh);
+  clh->gc = gc;
   clh->request_id = sh_msg->id;
-  clh->type = ntohl (sh_msg->type);
-  if (NULL != key)
+  if ( (GNUNET_DNSPARSER_TYPE_A == ntohl (sh_msg->type)) &&
+       (GNUNET_OK != v4_enabled) )
   {
-    clh->shorten_key = GNUNET_new (struct GNUNET_CRYPTO_EccPrivateKey);
-    *clh->shorten_key = *key;
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "LOOKUP: Query for A record but AF_INET not supported!");
+    send_lookup_response (clh, 0, NULL);
+    return;
   }
-  only_cached = ntohl (sh_msg->only_cached);
-  
-  if (strlen (name) > GNUNET_DNSPARSER_MAX_NAME_LENGTH) {
+  if ( (GNUNET_DNSPARSER_TYPE_AAAA == ntohl (sh_msg->type)) &&
+       (GNUNET_OK != v6_enabled) )
+  {
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                "LOOKUP: %s is too long", name);
-    clh->name = NULL;
+                "LOOKUP: Query for AAAA record but AF_INET6 not supported!");
     send_lookup_response (clh, 0, NULL);
     return;
   }
+  clh->lookup = GNS_resolver_lookup (&sh_msg->zone,
+                                     ntohl (sh_msg->type),
+                                     name,
+                                     key,
+                                     (enum GNUNET_GNS_LocalOptions) ntohs (sh_msg->options),
+                                     &send_lookup_response, clh);
+  GNUNET_STATISTICS_update (statistics,
+                            "Lookup attempts",
+                            1, GNUNET_NO);
+}
+
+/**
+ * Handle reverse lookup requests from client
+ *
+ * @param cls the closure
+ * @param client the client
+ * @param message the message
+ */
+static void
+handle_rev_lookup (void *cls,
+                   const struct ReverseLookupMessage *sh_msg)
+{
+  struct GnsClient *gc = cls;
+  struct ClientLookupHandle *clh;
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Received REVERSE_LOOKUP message\n");
+  GNUNET_SERVICE_client_continue (gc->client);
 
-  if ((GNUNET_DNSPARSER_TYPE_A == clh->type) &&
-      (GNUNET_OK != v4_enabled))
+  clh = GNUNET_new (struct ClientLookupHandle);
+  GNUNET_CONTAINER_DLL_insert (gc->clh_head, gc->clh_tail, clh);
+  clh->gc = gc;
+  clh->request_id = sh_msg->id;
+  clh->rev_lookup = GNS_reverse_lookup (&sh_msg->zone_pkey,
+                                        &sh_msg->root_pkey,
+                                        &send_reverse_lookup_response,
+                                        clh);
+  GNUNET_STATISTICS_update (statistics,
+                            "Reverse lookup attempts",
+                            1, GNUNET_NO);
+}
+
+
+/**
+ * The zone monitor is now in SYNC with the current state of the
+ * name store.  Start to perform periodic iterations.
+ *
+ * @param cls NULL
+ */
+static void
+monitor_sync_event (void *cls)
+{
+  GNUNET_assert (NULL == zone_publish_task);
+  zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
+                                                NULL);
+}
+
+
+/**
+ * The zone monitor is now in SYNC with the current state of the
+ * name store.  Start to perform periodic iterations.
+ *
+ * @param cls NULL
+ */
+static void
+handle_monitor_error (void *cls)
+{
+  if (NULL != zone_publish_task)
   {
-    GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
-               "LOOKUP: Query for A record but AF_INET not supported!");
-    clh->name = NULL;
-    send_lookup_response (clh, 0, NULL);
+    GNUNET_SCHEDULER_cancel (zone_publish_task);
+    zone_publish_task = NULL;
+  }
+  if (NULL != namestore_iter)
+  {
+    GNUNET_NAMESTORE_zone_iteration_stop (namestore_iter);
+    namestore_iter = NULL;
+  }
+  if (NULL != active_put)
+  {
+    GNUNET_DHT_put_cancel (active_put);
+    active_put = NULL;
+  }
+  zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start,
+                                                NULL);
+}
+
+/**
+ * Method called to inform about the ego to be used for the master zone
+ * for DNS interceptions.
+ *
+ * This function is only called ONCE, and 'NULL' being passed in
+ * @a ego does indicate that interception is not configured.
+ * If @a ego is non-NULL, we should start to intercept DNS queries
+ * and resolve ".gnu" queries using the given ego as the master zone.
+ *
+ * @param cls closure, our `const struct GNUNET_CONFIGURATION_Handle *c`
+ * @param ego ego handle
+ * @param ctx context for application to store data for this ego
+ *                 (during the lifetime of this process, initially NULL)
+ * @param name name assigned by the user for this ego,
+ *                   NULL if the user just deleted the ego and it
+ *                   must thus no longer be used
+ */
+static void
+identity_reverse_cb (void *cls,
+                       struct GNUNET_IDENTITY_Ego *ego,
+                       void **ctx,
+                       const char *name)
+{
+  identity_op = NULL;
+
+  if (NULL == ego)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+                _("No ego configured for `%s`\n"),
+                "gns-master");
+
     return;
   }
-  
-  if ((GNUNET_DNSPARSER_TYPE_AAAA == clh->type) &&
-      (GNUNET_OK != v6_enabled))
+  if (GNUNET_SYSERR ==
+      GNS_reverse_init (namestore_handle,
+                        GNUNET_IDENTITY_ego_get_private_key (ego),
+                        name))
   {
-    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-                "LOOKUP: Query for AAAA record but AF_INET6 not supported!");
-    clh->name = NULL;
-    send_lookup_response (clh, 0, NULL);
+    GNUNET_break (0);
+    GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
     return;
   }
-  
-  if (GNUNET_NO == ntohl (sh_msg->have_zone))
-    clh->zone = zone_hash;  /* Default zone */
-  else
-    clh->zone = sh_msg->zone;
-  
-  if (GNUNET_YES == auto_import_pkey)
+}
+
+
+
+/**
+ * Method called to inform about the ego to be used for the master zone
+ * for DNS interceptions.
+ *
+ * This function is only called ONCE, and 'NULL' being passed in
+ * @a ego does indicate that interception is not configured.
+ * If @a ego is non-NULL, we should start to intercept DNS queries
+ * and resolve ".gnu" queries using the given ego as the master zone.
+ *
+ * @param cls closure, our `const struct GNUNET_CONFIGURATION_Handle *c`
+ * @param ego ego handle
+ * @param ctx context for application to store data for this ego
+ *                 (during the lifetime of this process, initially NULL)
+ * @param name name assigned by the user for this ego,
+ *                   NULL if the user just deleted the ego and it
+ *                   must thus no longer be used
+ */
+static void
+identity_intercept_cb (void *cls,
+                       struct GNUNET_IDENTITY_Ego *ego,
+                       void **ctx,
+                       const char *name)
+{
+  const struct GNUNET_CONFIGURATION_Handle *cfg = cls;
+  struct GNUNET_CRYPTO_EcdsaPublicKey dns_root;
+  identity_op = NULL;
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Looking for gns-intercept ego\n");
+  identity_op = GNUNET_IDENTITY_get (identity_handle,
+                                     "gns-reverse",
+                                     &identity_reverse_cb,
+                                     (void*)cfg);
+
+
+  if (NULL == ego)
   {
-    gns_resolver_lookup_record (clh->zone, clh->zone, clh->type, clh->name,
-                                clh->shorten_key,
-                                default_lookup_timeout,
-                                clh->only_cached,
-                                &send_lookup_response, clh);  
+    GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+                _("No ego configured for `%s`\n"),
+                "gns-intercept");
+
+    return;
   }
-  else
+  GNUNET_IDENTITY_ego_get_public_key (ego,
+                                      &dns_root);
+  if (GNUNET_SYSERR ==
+      GNS_interceptor_init (&dns_root, cfg))
   {
-    gns_resolver_lookup_record (clh->zone, clh->zone, clh->type, name,
-                                NULL,
-                                default_lookup_timeout,
-                                only_cached,
-                                &send_lookup_response, clh);
+    GNUNET_break (0);
+    GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
+    return;
   }
-  GNUNET_STATISTICS_update (statistics,
-                            "Record lookup attempts", 1, GNUNET_NO);
 }
 
 
@@ -649,146 +1171,125 @@ handle_lookup (void *cls,
  * @param c configuration to use
  */
 static void
-run (void *cls, struct GNUNET_SERVER_Handle *server,
-     const struct GNUNET_CONFIGURATION_Handle *c)
+run (void *cls,
+     const struct GNUNET_CONFIGURATION_Handle *c,
+     struct GNUNET_SERVICE_Handle *service)
 {
-  static const struct GNUNET_SERVER_MessageHandler handlers[] = {
-    { &handle_lookup, NULL, GNUNET_MESSAGE_TYPE_GNS_LOOKUP, 0},
-    {NULL, NULL, 0, 0}
-  };
-  struct GNUNET_CRYPTO_EccPublicKey pkey;
   unsigned long long max_parallel_bg_queries = 0;
-  int ignore_pending = GNUNET_NO;
 
   v6_enabled = GNUNET_NETWORK_test_pf (PF_INET6);
   v4_enabled = GNUNET_NETWORK_test_pf (PF_INET);
-
+  min_relative_record_time = GNUNET_TIME_UNIT_FOREVER_REL;
   namestore_handle = GNUNET_NAMESTORE_connect (c);
   if (NULL == namestore_handle)
   {
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-               _("Failed to connect to the namestore!\n"));
+                _("Failed to connect to the namestore!\n"));
     GNUNET_SCHEDULER_shutdown ();
     return;
   }
-  
-  auto_import_pkey = GNUNET_NO;
-  if (GNUNET_YES ==
-      GNUNET_CONFIGURATION_get_value_yesno (c, "gns",
-                                            "AUTO_IMPORT_PKEY"))
+  namecache_handle = GNUNET_NAMECACHE_connect (c);
+  if (NULL == namecache_handle)
   {
-    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-               "Automatic PKEY import is enabled.\n");
-    auto_import_pkey = GNUNET_YES;
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                _("Failed to connect to the namecache!\n"));
+    GNUNET_SCHEDULER_shutdown ();
+    return;
   }
-  put_interval = INITIAL_PUT_INTERVAL;
-  zone_publish_time_window = DEFAULT_ZONE_PUBLISH_TIME_WINDOW;
 
+  put_interval = INITIAL_PUT_INTERVAL;
+  zone_publish_time_window_default = DEFAULT_ZONE_PUBLISH_TIME_WINDOW;
   if (GNUNET_OK ==
       GNUNET_CONFIGURATION_get_value_time (c, "gns",
-                                          "ZONE_PUBLISH_TIME_WINDOW",
-                                          &zone_publish_time_window))
+                                           "ZONE_PUBLISH_TIME_WINDOW",
+                                           &zone_publish_time_window_default))
   {
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-               "Time window for zone iteration: %s\n",
-               GNUNET_STRINGS_relative_time_to_string (zone_publish_time_window, GNUNET_YES));
+                "Time window for zone iteration: %s\n",
+                GNUNET_STRINGS_relative_time_to_string (zone_publish_time_window,
+                                                        GNUNET_YES));
   }
+  zone_publish_time_window = zone_publish_time_window_default;
   if (GNUNET_OK ==
       GNUNET_CONFIGURATION_get_value_number (c, "gns",
-                                            "MAX_PARALLEL_BACKGROUND_QUERIES",
-                                            &max_parallel_bg_queries))
-  {
-    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-               "Number of allowed parallel background queries: %llu\n",
-               max_parallel_bg_queries);
-  }
-
-  if (GNUNET_YES ==
-      GNUNET_CONFIGURATION_get_value_yesno (c, "gns",
-                                            "AUTO_IMPORT_CONFIRMATION_REQ"))
+                                             "MAX_PARALLEL_BACKGROUND_QUERIES",
+                                             &max_parallel_bg_queries))
   {
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-               "Auto import requires user confirmation\n");
-    ignore_pending = GNUNET_YES;
+                "Number of allowed parallel background queries: %llu\n",
+                max_parallel_bg_queries);
   }
 
-  if (GNUNET_OK ==
-      GNUNET_CONFIGURATION_get_value_time (c, "gns",
-                                          "DEFAULT_LOOKUP_TIMEOUT",
-                                          &default_lookup_timeout))
-  {
-    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-               "Default lookup timeout: %s\n",
-               GNUNET_STRINGS_relative_time_to_string (default_lookup_timeout,
-                                                       GNUNET_YES));
-  }
-  
   dht_handle = GNUNET_DHT_connect (c,
-                                  (unsigned int) max_parallel_bg_queries);
+                                   (unsigned int) max_parallel_bg_queries);
   if (NULL == dht_handle)
   {
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-               _("Could not connect to DHT!\n"));
-    GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
-    return;
-  }
-  
-  if (GNUNET_SYSERR ==
-      gns_resolver_init (namestore_handle, dht_handle, zone_hash, c,
-                        max_parallel_bg_queries,
-                        ignore_pending))
-  {
-    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-               _("Unable to initialize resolver!\n"));
+                _("Could not connect to DHT!\n"));
     GNUNET_SCHEDULER_add_now (&shutdown_task, NULL);
     return;
   }
 
-  if (GNUNET_YES ==
-      GNUNET_CONFIGURATION_get_value_yesno (c, "gns", "HIJACK_DNS"))
+  identity_handle = GNUNET_IDENTITY_connect (c,
+                                             NULL,
+                                             NULL);
+  if (NULL == identity_handle)
   {
     GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-               "DNS hijacking enabled. Connecting to DNS service.\n");
-
-    if (GNUNET_SYSERR ==
-       gns_interceptor_init (zone_hash, zone_key, c))
-    {
-      GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
-               "Failed to enable the DNS interceptor!\n");
-    }
+                "Could not connect to identity service!\n");
   }
-  
-  /**
-   * Schedule periodic put for our records We have roughly an hour for
-   * all records;
-   */
+  else
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "Looking for gns-intercept ego\n");
+    identity_op = GNUNET_IDENTITY_get (identity_handle,
+                                       "gns-intercept",
+                                       &identity_intercept_cb,
+                                       (void *) c);
+  }
+  GNS_resolver_init (namecache_handle,
+                     dht_handle,
+                     c,
+                     max_parallel_bg_queries);
+  GNS_shorten_init (namestore_handle,
+                    namecache_handle,
+                    dht_handle);
+  /* Schedule periodic put for our records. */
   first_zone_iteration = GNUNET_YES;
-  zone_publish_task = GNUNET_SCHEDULER_add_now (&publish_zone_dht_start, NULL);
-  GNUNET_SERVER_add_handlers (server, handlers);
   statistics = GNUNET_STATISTICS_create ("gns", c);
-  nc = GNUNET_SERVER_notification_context_create (server, 1);
-  GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &shutdown_task,
-                                NULL);
+  zmon = GNUNET_NAMESTORE_zone_monitor_start (c,
+                                              NULL,
+                                              GNUNET_NO,
+                                              &handle_monitor_error,
+                                              NULL,
+                                              &handle_monitor_event,
+                                              NULL,
+                                              &monitor_sync_event,
+                                              NULL);
+  GNUNET_break (NULL != zmon);
+  GNUNET_SCHEDULER_add_shutdown (&shutdown_task, NULL);
 }
 
 
 /**
- * The main function for the GNS service.
- *
- * @param argc number of arguments from the command line
- * @param argv command line arguments
- * @return 0 ok, 1 on error
+ * Define "main" method using service macro.
  */
-int
-main (int argc, char *const *argv)
-{
-  int ret;
+GNUNET_SERVICE_MAIN
+("gns",
+ GNUNET_SERVICE_OPTION_NONE,
+ &run,
+ &client_connect_cb,
+ &client_disconnect_cb,
+ NULL,
+ GNUNET_MQ_hd_var_size (lookup,
+                        GNUNET_MESSAGE_TYPE_GNS_LOOKUP,
+                        struct LookupMessage,
+                        NULL),
+ GNUNET_MQ_hd_fixed_size (rev_lookup,
+                          GNUNET_MESSAGE_TYPE_GNS_REVERSE_LOOKUP,
+                          struct ReverseLookupMessage,
+                          NULL),
+ GNUNET_MQ_handler_end());
 
-  ret =
-      (GNUNET_OK ==
-       GNUNET_SERVICE_run (argc, argv, "gns", GNUNET_SERVICE_OPTION_NONE, &run,
-                           NULL)) ? 0 : 1;
-  return ret;
-}
 
 /* end of gnunet-service-gns.c */