arg
[oweals/gnunet.git] / src / fs / fs_search.c
index 85d65f483b3f734cb939d0f05de8c430d480df2f..77b66f82f48bf06ca81e1b3dd597d25fce2ccfd2 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
  * @file fs/fs_search.c
  * @brief Helper functions for searching.
  * @author Christian Grothoff
- *
- * TODO:
- * - handle SKS updates searches nicely (can wait)
- * - handle availability probes (can wait)
- * - make operations persistent (can wait)
- * - handle namespace advertisements (can wait)
- * - add support for pushing "already seen" information
- *   to FS service for bloomfilter (can wait)
  */
 
 #include "platform.h"
 #include "gnunet_protocols.h"
 #include "fs.h"
 
-#define DEBUG_SEARCH GNUNET_YES
-
-
+#define DEBUG_SEARCH GNUNET_NO
 
 /**
- * Fill in all of the generic fields for 
- * a search event.
+ * Fill in all of the generic fields for a search event and
+ * call the callback.
  *
  * @param pi structure to fill in
  * @param sc overall search context
+ * @return value returned by the callback
  */
-static void
-make_search_status (struct GNUNET_FS_ProgressInfo *pi,
-                   struct GNUNET_FS_SearchContext *sc)
-{
+void *
+GNUNET_FS_search_make_status_ (struct GNUNET_FS_ProgressInfo *pi,
+                              struct GNUNET_FS_SearchContext *sc)
+{  
+  void *ret;
   pi->value.search.sc = sc;
   pi->value.search.cctx
     = sc->client_info;
   pi->value.search.pctx
-    = (sc->parent == NULL) ? NULL : sc->parent->client_info;
+    = (sc->psearch_result == NULL) ? NULL : sc->psearch_result->client_info;
   pi->value.search.query 
     = sc->uri;
   pi->value.search.duration = GNUNET_TIME_absolute_get_duration (sc->start_time);
   pi->value.search.anonymity = sc->anonymity;
+  ret =  sc->h->upcb (sc->h->upcb_cls,
+                     pi);
+  return ret;
 }
 
 
@@ -71,7 +66,7 @@ make_search_status (struct GNUNET_FS_ProgressInfo *pi,
  * 
  * @param cls points to the URI we check against
  * @param key not used
- * @param value a "struct SearchResult" who's URI we
+ * @param value a "struct GNUNET_FS_SearchResult" who's URI we
  *        should compare with
  * @return GNUNET_SYSERR if the result is present,
  *         GNUNET_OK otherwise
@@ -82,7 +77,7 @@ test_result_present (void *cls,
                     void *value)
 {
   const struct GNUNET_FS_Uri *uri = cls;
-  struct SearchResult *sr = value;
+  struct GNUNET_FS_SearchResult *sr = value;
 
   if (GNUNET_FS_uri_test_equal (uri,
                                sr->uri))
@@ -100,16 +95,16 @@ test_result_present (void *cls,
  */
 static void
 notify_client_chk_result (struct GNUNET_FS_SearchContext *sc, 
-                         struct SearchResult *sr)
+                         struct GNUNET_FS_SearchResult *sr)
 {                        
   struct GNUNET_FS_ProgressInfo pi;
 
   pi.status = GNUNET_FS_STATUS_SEARCH_RESULT;
-  make_search_status (&pi, sc);
   pi.value.search.specifics.result.meta = sr->meta;
   pi.value.search.specifics.result.uri = sr->uri;
-  sr->client_info = sc->h->upcb (sc->h->upcb_cls,
-                                &pi);
+  pi.value.search.specifics.result.result = sr;
+  pi.value.search.specifics.result.applicability_rank = sr->optional_support;
+  sr->client_info = GNUNET_FS_search_make_status_ (&pi, sc);
 }
 
 
@@ -122,12 +117,11 @@ notify_client_chk_result (struct GNUNET_FS_SearchContext *sc,
  */
 static void
 notify_client_chk_update (struct GNUNET_FS_SearchContext *sc, 
-                         struct SearchResult *sr)
+                         struct GNUNET_FS_SearchResult *sr)
 {                        
   struct GNUNET_FS_ProgressInfo pi;
 
   pi.status = GNUNET_FS_STATUS_SEARCH_UPDATE;
-  make_search_status (&pi, sc);
   pi.value.search.specifics.update.cctx = sr->client_info;
   pi.value.search.specifics.update.meta = sr->meta;
   pi.value.search.specifics.update.uri = sr->uri;
@@ -137,8 +131,7 @@ notify_client_chk_update (struct GNUNET_FS_SearchContext *sc,
     = sr->availability_trials;
   pi.value.search.specifics.update.applicability_rank 
     = sr->optional_support;
-  sr->client_info = sc->h->upcb (sc->h->upcb_cls,
-                                &pi);
+  sr->client_info = GNUNET_FS_search_make_status_ (&pi, sc);
 }
 
 
@@ -156,17 +149,17 @@ struct GetResultContext
    * Where to store a pointer to the search
    * result struct if we found a match.
    */
-  struct SearchResult *sr;
+  struct GNUNET_FS_SearchResult *sr;
 };
 
 
 /**
- * Check if the given result is identical
- * to the given URI and if so return it.
+ * Check if the given result is identical to the given URI and if so
+ * return it.
  * 
  * @param cls a "struct GetResultContext"
  * @param key not used
- * @param value a "struct SearchResult" who's URI we
+ * @param value a "struct GNUNET_FS_SearchResult" who's URI we
  *        should compare with
  * @return GNUNET_OK
  */
@@ -176,7 +169,7 @@ get_result_present (void *cls,
                     void *value)
 {
   struct GetResultContext *grc = cls;
-  struct SearchResult *sr = value;
+  struct GNUNET_FS_SearchResult *sr = value;
 
   if (GNUNET_FS_uri_test_equal (grc->uri,
                                sr->uri))
@@ -186,9 +179,202 @@ get_result_present (void *cls,
 
 
 /**
- * We have received a KSK result.  Check
- * how it fits in with the overall query
- * and notify the client accordingly.
+ * Signal result of last probe to client and then schedule next
+ * probe.
+ */
+static void
+signal_probe_result (struct GNUNET_FS_SearchResult *sr)
+{
+  struct GNUNET_FS_ProgressInfo pi;
+
+  pi.status = GNUNET_FS_STATUS_SEARCH_START;
+  pi.value.search.specifics.update.cctx = sr->client_info;
+  pi.value.search.specifics.update.meta = sr->meta;
+  pi.value.search.specifics.update.uri = sr->uri;
+  pi.value.search.specifics.update.availability_rank = sr->availability_success;
+  pi.value.search.specifics.update.availability_certainty = sr->availability_trials;
+  pi.value.search.specifics.update.applicability_rank = sr->optional_support;
+  sr->sc->client_info = GNUNET_FS_search_make_status_ (&pi, sr->sc);
+  GNUNET_FS_search_start_probe_ (sr);
+}
+
+
+/**
+ * Handle the case where we have failed to receive a response for our probe.
+ *
+ * @param cls our 'struct GNUNET_FS_SearchResult*'
+ * @param tc scheduler context
+ */
+static void
+probe_failure_handler (void *cls,
+                      const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct GNUNET_FS_SearchResult *sr = cls;
+  sr->availability_trials++;
+  GNUNET_FS_search_result_sync_ (sr);
+  signal_probe_result (sr);
+}
+
+
+/**
+ * Handle the case where we have gotten a response for our probe.
+ *
+ * @param cls our 'struct GNUNET_FS_SearchResult*'
+ * @param tc scheduler context
+ */
+static void
+probe_success_handler (void *cls,
+                      const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct GNUNET_FS_SearchResult *sr = cls;
+  sr->availability_trials++;
+  sr->availability_success++;
+  GNUNET_FS_search_result_sync_ (sr);
+  signal_probe_result (sr);
+}
+
+
+/**
+ * Notification of FS that a search probe has made progress.
+ * This function is used INSTEAD of the client's event handler
+ * for downloads where the GNUNET_FS_DOWNLOAD_IS_PROBE flag is set.
+ *
+ * @param cls closure, always NULL (!), actual closure
+ *        is in the client-context of the info struct
+ * @param info details about the event, specifying the event type
+ *        and various bits about the event
+ * @return client-context (for the next progress call
+ *         for this operation; should be set to NULL for
+ *         SUSPEND and STOPPED events).  The value returned
+ *         will be passed to future callbacks in the respective
+ *         field in the GNUNET_FS_ProgressInfo struct.
+ */
+void*
+GNUNET_FS_search_probe_progress_ (void *cls,
+                                 const struct GNUNET_FS_ProgressInfo *info)
+{
+  struct GNUNET_FS_SearchResult *sr = info->value.download.cctx;
+  struct GNUNET_TIME_Relative dur;
+
+  switch (info->status)
+    {
+    case GNUNET_FS_STATUS_DOWNLOAD_START:
+      /* ignore */
+      break;
+    case GNUNET_FS_STATUS_DOWNLOAD_RESUME:
+      /* probes should never be resumed */
+      GNUNET_assert (0);
+      break;
+    case GNUNET_FS_STATUS_DOWNLOAD_SUSPEND:
+      /* probes should never be suspended */
+      GNUNET_break (0);
+      break;
+    case GNUNET_FS_STATUS_DOWNLOAD_PROGRESS:
+      /* ignore */
+      break;
+    case GNUNET_FS_STATUS_DOWNLOAD_ERROR:
+      if (sr->probe_cancel_task != GNUNET_SCHEDULER_NO_TASK)
+       {
+         GNUNET_SCHEDULER_cancel (sr->probe_cancel_task);
+         sr->probe_cancel_task = GNUNET_SCHEDULER_NO_TASK;
+       }     
+      sr->probe_cancel_task = GNUNET_SCHEDULER_add_delayed (sr->remaining_probe_time,
+                                                           &probe_failure_handler,
+                                                           sr);
+      break;
+    case GNUNET_FS_STATUS_DOWNLOAD_COMPLETED:
+      if (sr->probe_cancel_task != GNUNET_SCHEDULER_NO_TASK)
+       {
+         GNUNET_SCHEDULER_cancel (sr->probe_cancel_task);
+         sr->probe_cancel_task = GNUNET_SCHEDULER_NO_TASK;
+       }     
+      sr->probe_cancel_task = GNUNET_SCHEDULER_add_delayed (sr->remaining_probe_time,
+                                                           &probe_success_handler,
+                                                           sr);
+      break;
+    case GNUNET_FS_STATUS_DOWNLOAD_STOPPED:
+      if (sr->probe_cancel_task != GNUNET_SCHEDULER_NO_TASK)
+       {
+         GNUNET_SCHEDULER_cancel (sr->probe_cancel_task);
+         sr->probe_cancel_task = GNUNET_SCHEDULER_NO_TASK;
+       }     
+      sr = NULL;
+      break;
+    case GNUNET_FS_STATUS_DOWNLOAD_ACTIVE:
+      GNUNET_assert (sr->probe_cancel_task == GNUNET_SCHEDULER_NO_TASK);
+      sr->probe_active_time = GNUNET_TIME_absolute_get ();
+      sr->probe_cancel_task = GNUNET_SCHEDULER_add_delayed (sr->remaining_probe_time,
+                                                           &probe_failure_handler,
+                                                           sr);
+      break;
+    case GNUNET_FS_STATUS_DOWNLOAD_INACTIVE:
+      if (sr->probe_cancel_task != GNUNET_SCHEDULER_NO_TASK)
+       {
+         GNUNET_SCHEDULER_cancel (sr->probe_cancel_task);
+         sr->probe_cancel_task = GNUNET_SCHEDULER_NO_TASK;
+       }
+      dur = GNUNET_TIME_absolute_get_duration (sr->probe_active_time);
+      sr->remaining_probe_time = GNUNET_TIME_relative_subtract (sr->remaining_probe_time,
+                                                               dur);
+      GNUNET_FS_search_result_sync_ (sr);
+      break;
+    default:
+      GNUNET_break (0);
+      return NULL;
+    }
+  return sr;
+}
+
+
+/**
+ * Start download probes for the given search result.
+ *
+ * @param sr the search result
+ */
+void
+GNUNET_FS_search_start_probe_ (struct GNUNET_FS_SearchResult *sr)
+{
+  uint64_t off;
+  uint64_t len;
+  
+  if (sr->probe_ctx != NULL)
+    return;
+  if (sr->download != NULL)
+    return;
+  if (0 == (sr->sc->h->flags & GNUNET_FS_FLAGS_DO_PROBES))
+    return;
+  if (sr->availability_trials > AVAILABILITY_TRIALS_MAX)
+    return;
+  len = GNUNET_FS_uri_chk_get_file_size (sr->uri);
+  if (len == 0)
+    return;
+  if ( (len <= DBLOCK_SIZE) && (sr->availability_success > 0))
+    return;
+  off = len / DBLOCK_SIZE;
+  if (off > 0)
+    off = GNUNET_CRYPTO_random_u32 (GNUNET_CRYPTO_QUALITY_WEAK, off);
+  off *= DBLOCK_SIZE;
+  if (len - off < DBLOCK_SIZE)
+    len = len - off;
+  else
+    len = DBLOCK_SIZE;
+  sr->remaining_probe_time = GNUNET_TIME_relative_multiply (sr->sc->h->avg_block_latency,
+                                                           2 * (1 + sr->availability_trials));
+  sr->probe_ctx = GNUNET_FS_download_start (sr->sc->h,
+                                           sr->uri,
+                                           sr->meta,
+                                           NULL, NULL,
+                                           off, len, 
+                                           sr->sc->anonymity,
+                                           GNUNET_FS_DOWNLOAD_NO_TEMPORARIES |
+                                           GNUNET_FS_DOWNLOAD_IS_PROBE,
+                                           sr, NULL);    
+}
+
+
+/**
+ * We have received a KSK result.  Check how it fits in with the
+ * overall query and notify the client accordingly.
  *
  * @param sc context for the overall query
  * @param ent entry for the specific keyword
@@ -203,19 +389,12 @@ process_ksk_result (struct GNUNET_FS_SearchContext *sc,
                    const struct GNUNET_CONTAINER_MetaData *meta)
 {
   GNUNET_HashCode key;
-  struct SearchResult *sr;
+  struct GNUNET_FS_SearchResult *sr;
   struct GetResultContext grc;
   int is_new;
 
   /* check if new */
-  if (! GNUNET_FS_uri_test_ksk (uri))
-    {
-      GNUNET_break_op (0);
-      return;
-    }
-  GNUNET_CRYPTO_hash_xor (&uri->data.chk.chk.key,
-                         &uri->data.chk.chk.query,
-                         &key);
+  GNUNET_FS_uri_to_key (uri, &key);
   if (GNUNET_SYSERR ==
       GNUNET_CONTAINER_multihashmap_get_multiple (ent->results,
                                                  &key,
@@ -233,10 +412,12 @@ process_ksk_result (struct GNUNET_FS_SearchContext *sc,
   is_new = (NULL == sr) || (sr->mandatory_missing > 0);
   if (NULL == sr)
     {
-      sr = GNUNET_malloc (sizeof (struct SearchResult));
+      sr = GNUNET_malloc (sizeof (struct GNUNET_FS_SearchResult));
+      sr->sc = sc;
       sr->uri = GNUNET_FS_uri_dup (uri);
       sr->meta = GNUNET_CONTAINER_meta_data_duplicate (meta);
       sr->mandatory_missing = sc->mandatory_count;
+      sr->key = key;
       GNUNET_CONTAINER_multihashmap_put (sc->master_result_map,
                                         &key,
                                         sr,
@@ -244,7 +425,7 @@ process_ksk_result (struct GNUNET_FS_SearchContext *sc,
     }
   else
     {
-      /* FIXME: consider combining the meta data */
+      GNUNET_CONTAINER_meta_data_merge (sr->meta, meta);
     }
   /* check if mandatory satisfied */
   if (ent->mandatory)
@@ -257,7 +438,8 @@ process_ksk_result (struct GNUNET_FS_SearchContext *sc,
     notify_client_chk_result (sc, sr);
   else
     notify_client_chk_update (sc, sr);
-  /* FIXME: consider starting probes for "sr" */
+  GNUNET_FS_search_result_sync_ (sr);
+  GNUNET_FS_search_start_probe_ (sr);
 }
 
 
@@ -268,20 +450,23 @@ process_ksk_result (struct GNUNET_FS_SearchContext *sc,
  * @param uri specifies the search parameters; can be
  *        a KSK URI or an SKS URI.
  * @param anonymity desired level of anonymity
- * @param parent parent search (for namespace update searches)
+ * @param options options for the search
+ * @param cctx client context
+ * @param psearch parent search result (for namespace update searches)
  * @return context that can be used to control the search
  */
 static struct GNUNET_FS_SearchContext *
 search_start (struct GNUNET_FS_Handle *h,
              const struct GNUNET_FS_Uri *uri,
              uint32_t anonymity,
-             struct GNUNET_FS_SearchContext *parent);
+             enum GNUNET_FS_SearchOptions options,
+             void *cctx,
+             struct GNUNET_FS_SearchResult *psearch);
 
 
 /**
- * We have received an SKS result.  Start
- * searching for updates and notify the
- * client if it is a new result.
+ * We have received an SKS result.  Start searching for updates and
+ * notify the client if it is a new result.
  *
  * @param sc context for the overall query
  * @param id_update identifier for updates, NULL for none
@@ -296,14 +481,10 @@ process_sks_result (struct GNUNET_FS_SearchContext *sc,
 {
   struct GNUNET_FS_Uri uu;
   GNUNET_HashCode key;
-  struct SearchResult *sr;
+  struct GNUNET_FS_SearchResult *sr;
 
   /* check if new */
-  if (! GNUNET_FS_uri_test_ksk (uri))
-    {
-      GNUNET_break_op (0);
-      return;
-    }
+  GNUNET_FS_uri_to_key (uri, &key);
   GNUNET_CRYPTO_hash_xor (&uri->data.chk.chk.key,
                          &uri->data.chk.chk.query,
                          &key);
@@ -313,15 +494,17 @@ process_sks_result (struct GNUNET_FS_SearchContext *sc,
                                                  &test_result_present,
                                                  (void*) uri))
     return; /* duplicate result */
-  sr = GNUNET_malloc (sizeof (struct SearchResult));
+  sr = GNUNET_malloc (sizeof (struct GNUNET_FS_SearchResult));
+  sr->sc = sc;
   sr->uri = GNUNET_FS_uri_dup (uri);
   sr->meta = GNUNET_CONTAINER_meta_data_duplicate (meta);
+  sr->key = key;
   GNUNET_CONTAINER_multihashmap_put (sc->master_result_map,
                                     &key,
                                     sr,
                                     GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
-  /* FIXME: consider starting probes for "sr" */
-
+  GNUNET_FS_search_result_sync_ (sr);
+  GNUNET_FS_search_start_probe_ (sr);
   /* notify client */
   notify_client_chk_result (sc, sr);
   /* search for updates */
@@ -330,13 +513,13 @@ process_sks_result (struct GNUNET_FS_SearchContext *sc,
   uu.type = sks;
   uu.data.sks.namespace = sc->uri->data.sks.namespace;
   uu.data.sks.identifier = GNUNET_strdup (id_update);
-  /* FIXME: should attach update search
-     to the individual result, not
-     the entire SKS search! */
-  search_start (sc->h,
-               &uu,
-               sc->anonymity,
-               sc);
+  (void) search_start (sc->h,
+                      &uu,
+                      sc->anonymity,
+                      sc->options,
+                      NULL,
+                      sr);
+  GNUNET_free (uu.data.sks.identifier);
 }
 
 
@@ -380,11 +563,15 @@ process_kblock (struct GNUNET_FS_SearchContext *sc,
     }
   /* decrypt */
   GNUNET_CRYPTO_hash_to_aes_key (&sc->requests[i].key, &skey, &iv);
-  GNUNET_CRYPTO_aes_encrypt (&kb[1],
-                            size - sizeof (struct KBlock),
-                            &skey,
-                            &iv,
-                            pt);
+  if (-1 == GNUNET_CRYPTO_aes_decrypt (&kb[1],
+                                      size - sizeof (struct KBlock),
+                                      &skey,
+                                      &iv,
+                                      pt))
+    {
+      GNUNET_break (0);
+      return;
+    }
   /* parse */
   eos = memchr (pt, 0, sizeof (pt));
   if (NULL == eos)
@@ -393,8 +580,11 @@ process_kblock (struct GNUNET_FS_SearchContext *sc,
       return;
     }
   j = eos - pt + 1;
-  meta = GNUNET_CONTAINER_meta_data_deserialize (&pt[j],
-                                                sizeof (pt) - j);
+  if (sizeof (pt) == j)
+    meta = GNUNET_CONTAINER_meta_data_create ();
+  else
+    meta = GNUNET_CONTAINER_meta_data_deserialize (&pt[j],
+                                                  sizeof (pt) - j);
   if (meta == NULL)
     {
       GNUNET_break_op (0);       /* kblock malformed */
@@ -417,6 +607,101 @@ process_kblock (struct GNUNET_FS_SearchContext *sc,
 }
 
 
+/**
+ * Process a keyword-search result with a namespace advertisment.
+ *
+ * @param sc our search context
+ * @param nb the nblock
+ * @param size size of nb
+ */
+static void
+process_nblock (struct GNUNET_FS_SearchContext *sc,
+               const struct NBlock *nb,
+               size_t size)
+{
+  unsigned int i;
+  size_t j;
+  GNUNET_HashCode q;
+  char pt[size - sizeof (struct NBlock)];
+  struct GNUNET_CRYPTO_AesSessionKey skey;
+  struct GNUNET_CRYPTO_AesInitializationVector iv;
+  const char *eos;
+  struct GNUNET_CONTAINER_MetaData *meta;
+  struct GNUNET_FS_Uri *uri;
+  char *uris;
+  
+  GNUNET_CRYPTO_hash (&nb->keyspace,
+                     sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
+                     &q);
+  /* find key */
+  for (i=0;i<sc->uri->data.ksk.keywordCount;i++)
+    if (0 == memcmp (&q,
+                    &sc->requests[i].query,
+                    sizeof (GNUNET_HashCode)))
+      break;
+  if (i == sc->uri->data.ksk.keywordCount)
+    {
+      /* oops, does not match any of our keywords!? */
+      GNUNET_break (0);
+      return;
+    }
+  /* decrypt */
+  GNUNET_CRYPTO_hash_to_aes_key (&sc->requests[i].key, &skey, &iv);
+  if (-1 == GNUNET_CRYPTO_aes_decrypt (&nb[1],
+                                      size - sizeof (struct NBlock),
+                                      &skey,
+                                      &iv,
+                                      pt))
+    {
+      GNUNET_break (0);
+      return;
+    }
+  /* parse */
+  eos = memchr (pt, 0, sizeof (pt));
+  if (NULL == eos)
+    {
+      GNUNET_break_op (0);
+      return;
+    }
+  j = eos - pt + 1;
+  if (sizeof (pt) == j)
+    meta = GNUNET_CONTAINER_meta_data_create ();
+  else
+    meta = GNUNET_CONTAINER_meta_data_deserialize (&pt[j],
+                                                  sizeof (pt) - j);
+  if (meta == NULL)
+    {
+      GNUNET_break_op (0);       /* nblock malformed */
+      return;
+    }
+
+  uri = GNUNET_malloc (sizeof (struct GNUNET_FS_Uri));
+  uri->type = sks;
+  uri->data.sks.identifier = GNUNET_strdup (pt);
+  GNUNET_CRYPTO_hash (&nb->subspace,
+                     sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
+                     &uri->data.sks.namespace);
+  uris = GNUNET_FS_uri_to_string (uri);
+  GNUNET_CONTAINER_meta_data_insert (meta,
+                                    "<gnunet>",
+                                    EXTRACTOR_METATYPE_URI,
+                                    EXTRACTOR_METAFORMAT_UTF8,
+                                    "text/plain",
+                                    uris,
+                                    strlen (uris)+1);
+  GNUNET_free (uris);
+  GNUNET_PSEUDONYM_add (sc->h->cfg,
+                       &uri->data.sks.namespace,
+                       meta);
+  /* process */
+  process_ksk_result (sc, &sc->requests[i], uri, meta);
+
+  /* clean up */
+  GNUNET_CONTAINER_meta_data_destroy (meta);
+  GNUNET_FS_uri_destroy (uri);
+}
+
+
 /**
  * Process a namespace-search result.
  *
@@ -448,11 +733,15 @@ process_sblock (struct GNUNET_FS_SearchContext *sc,
                      strlen (identifier), 
                      &key);
   GNUNET_CRYPTO_hash_to_aes_key (&key, &skey, &iv);
-  GNUNET_CRYPTO_aes_encrypt (&sb[1],
-                            len,
-                            &skey,
-                            &iv,
-                            pt);
+  if (-1 == GNUNET_CRYPTO_aes_decrypt (&sb[1],
+                                      len,
+                                      &skey,
+                                      &iv,
+                                      pt))
+    {
+      GNUNET_break (0);
+      return;
+    }
   /* parse */
   off = GNUNET_STRINGS_buffer_tokenize (pt,
                                        len, 
@@ -474,6 +763,9 @@ process_sblock (struct GNUNET_FS_SearchContext *sc,
   uri = GNUNET_FS_uri_parse (uris, &emsg);
   if (uri == NULL)
     {
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                 "Failed to parse URI `%s': %s\n",
+                 uris, emsg);
       GNUNET_break_op (0);     /* sblock malformed */
       GNUNET_free_non_null (emsg);
       GNUNET_CONTAINER_meta_data_destroy (meta);
@@ -498,16 +790,20 @@ process_sblock (struct GNUNET_FS_SearchContext *sc,
  */
 static void
 process_result (struct GNUNET_FS_SearchContext *sc,
-               uint32_t type,
+               enum GNUNET_BLOCK_Type type,
                struct GNUNET_TIME_Absolute expiration,
                const void *data,
                size_t size)
 {
-  if (GNUNET_TIME_absolute_get_duration (expiration).value > 0)
-    return; /* result expired */
+  if (GNUNET_TIME_absolute_get_duration (expiration).rel_value > 0)
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                 "Result received has already expired.\n");
+      return; /* result expired */
+    }
   switch (type)
     {
-    case GNUNET_DATASTORE_BLOCKTYPE_KBLOCK:
+    case GNUNET_BLOCK_TYPE_FS_KBLOCK:
       if (! GNUNET_FS_uri_test_ksk (sc->uri))
        {
          GNUNET_break (0);
@@ -520,8 +816,8 @@ process_result (struct GNUNET_FS_SearchContext *sc,
        }
       process_kblock (sc, data, size);
       break;
-    case GNUNET_DATASTORE_BLOCKTYPE_SBLOCK:
-      if (! GNUNET_FS_uri_test_ksk (sc->uri))
+    case GNUNET_BLOCK_TYPE_FS_SBLOCK:
+      if (! GNUNET_FS_uri_test_sks (sc->uri))
        {
          GNUNET_break (0);
          return;
@@ -533,10 +829,29 @@ process_result (struct GNUNET_FS_SearchContext *sc,
        }
       process_sblock (sc, data, size);
       break;
-    case GNUNET_DATASTORE_BLOCKTYPE_ANY:
-    case GNUNET_DATASTORE_BLOCKTYPE_DBLOCK:
-    case GNUNET_DATASTORE_BLOCKTYPE_ONDEMAND:
-    case GNUNET_DATASTORE_BLOCKTYPE_IBLOCK:
+    case GNUNET_BLOCK_TYPE_FS_NBLOCK:
+      if (! GNUNET_FS_uri_test_ksk (sc->uri))
+       {
+         GNUNET_break (0);
+         return;
+       }
+      if (sizeof (struct NBlock) > size)
+       {
+         GNUNET_break_op (0);
+         return;
+       }
+      process_nblock (sc, data, size);
+      break;
+    case GNUNET_BLOCK_TYPE_ANY:
+      GNUNET_break (0);
+      break;
+    case GNUNET_BLOCK_TYPE_FS_DBLOCK:
+      GNUNET_break (0);
+      break;
+    case GNUNET_BLOCK_TYPE_FS_ONDEMAND:
+      GNUNET_break (0);
+      break;
+    case GNUNET_BLOCK_TYPE_FS_IBLOCK:
       GNUNET_break (0);
       break;
     default:
@@ -571,23 +886,26 @@ receive_results (void *cls,
                 const struct GNUNET_MessageHeader * msg)
 {
   struct GNUNET_FS_SearchContext *sc = cls;
-  const struct ContentMessage *cm;
+  const struct PutMessage *cm;
   uint16_t msize;
 
   if ( (NULL == msg) ||
-       (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_FS_CONTENT) ||
-       (ntohs (msg->size) <= sizeof (struct ContentMessage)) )
+       (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_FS_PUT) ||
+       (ntohs (msg->size) <= sizeof (struct PutMessage)) )
     {
       try_reconnect (sc);
       return;
     }
   msize = ntohs (msg->size);
-  cm = (const struct ContentMessage*) msg;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+             "Receiving %u bytes of result from fs service\n",
+             msize);
+  cm = (const struct PutMessage*) msg;
   process_result (sc, 
                  ntohl (cm->type),
                  GNUNET_TIME_absolute_ntoh (cm->expiration),
                  &cm[1],
-                 msize - sizeof (struct ContentMessage));
+                 msize - sizeof (struct PutMessage));
   /* continue receiving */
   GNUNET_CLIENT_receive (sc->client,
                         &receive_results,
@@ -596,6 +914,110 @@ receive_results (void *cls,
 }
 
 
+/**
+ * Schedule the transmission of the (next) search request
+ * to the service.
+ *
+ * @param sc context for the search
+ */
+static void
+schedule_transmit_search_request (struct GNUNET_FS_SearchContext *sc);
+
+
+/**
+ * Closure for 'build_result_set'.
+ */
+struct MessageBuilderContext
+{
+  /**
+   * How many entries can we store to xoff.
+   */
+  unsigned int put_cnt;
+
+  /**
+   * How many entries should we skip.
+   */
+  unsigned int skip_cnt;
+
+  /**
+   * Where to store the keys.
+   */
+  GNUNET_HashCode *xoff;
+
+  /**
+   * Search context we are iterating for.
+   */
+  struct GNUNET_FS_SearchContext *sc;
+
+  /**
+   * URI the search result must match, NULL for any
+   */
+  struct GNUNET_FS_Uri *uri;
+};
+
+
+/**
+ * Iterating over the known results, pick those
+ * matching the given result range and store
+ * their keys at 'xoff'.
+ *
+ * @param cls the 'struct MessageBuilderContext'
+ * @param key key for a result
+ * @param value the search result
+ * @return GNUNET_OK to continue iterating
+ */
+static int
+build_result_set (void *cls,
+                 const GNUNET_HashCode *key,
+                 void *value)
+{
+  struct MessageBuilderContext *mbc = cls;
+  struct GNUNET_FS_SearchResult *sr = value;
+  
+  if ( (mbc->uri != NULL) &&
+       (GNUNET_YES != GNUNET_FS_uri_test_equal (mbc->uri,
+                                               sr->uri)) )
+    return GNUNET_OK;
+  if (mbc->skip_cnt > 0)
+    {
+      mbc->skip_cnt--;
+      return GNUNET_OK;
+    }
+  if (mbc->put_cnt == 0)
+    return GNUNET_SYSERR;
+  mbc->sc->search_request_map_offset++;
+  mbc->xoff[--mbc->put_cnt] = *key;
+  return GNUNET_OK;
+}
+
+
+/**
+ * Iterating over the known results, count those
+ * matching the given result range and increment
+ * put count for each.
+ *
+ * @param cls the 'struct MessageBuilderContext'
+ * @param key key for a result
+ * @param value the search result
+ * @return GNUNET_OK to continue iterating
+ */
+static int
+find_result_set (void *cls,
+                 const GNUNET_HashCode *key,
+                 void *value)
+{
+  struct MessageBuilderContext *mbc = cls;
+  struct GNUNET_FS_SearchResult *sr = value;
+  
+  if ( (mbc->uri != NULL) &&
+       (GNUNET_YES != GNUNET_FS_uri_test_equal (mbc->uri,
+                                               sr->uri)) )
+    return GNUNET_OK;
+  mbc->put_cnt++;
+  return GNUNET_OK;
+}
+
+
 /**
  * We're ready to transmit the search request to the
  * file-sharing service.  Do it.
@@ -611,48 +1033,108 @@ transmit_search_request (void *cls,
                         void *buf)
 {
   struct GNUNET_FS_SearchContext *sc = cls;
+  struct MessageBuilderContext mbc;
   size_t msize;
   struct SearchMessage *sm;
-  unsigned int i;
   const char *identifier;
+  GNUNET_HashCode key;
   GNUNET_HashCode idh;
+  unsigned int sqms;
 
   if (NULL == buf)
     {
       try_reconnect (sc);
       return 0;
     }
+  mbc.sc = sc;
+  mbc.skip_cnt = sc->search_request_map_offset;
+  sm = buf;
+  sm->header.type = htons (GNUNET_MESSAGE_TYPE_FS_START_SEARCH);
+  mbc.xoff = (GNUNET_HashCode* ) &sm[1];
   if (GNUNET_FS_uri_test_ksk (sc->uri))
     {
-      msize = sizeof (struct SearchMessage) * sc->uri->data.ksk.keywordCount;
+      msize = sizeof (struct SearchMessage);
       GNUNET_assert (size >= msize);
-      sm = buf;
-      memset (sm, 0, msize);
-      for (i=0;i<sc->uri->data.ksk.keywordCount;i++)
+      mbc.uri = NULL;
+      mbc.put_cnt = 0;
+      GNUNET_CONTAINER_multihashmap_iterate (sc->master_result_map,
+                                            &find_result_set,
+                                            &mbc);
+      sqms = mbc.put_cnt;
+      mbc.put_cnt = (size - msize) / sizeof (GNUNET_HashCode);
+      mbc.put_cnt = GNUNET_MIN (mbc.put_cnt,
+                               sqms - mbc.skip_cnt);
+      if (sc->search_request_map_offset < sqms)
+       GNUNET_assert (mbc.put_cnt > 0);
+
+      sm->header.size = htons (msize);
+      if (0 != (sc->options & GNUNET_FS_SEARCH_OPTION_LOOPBACK_ONLY))
+       sm->options = htonl (1);
+      else
+       sm->options = htonl (0);          
+      sm->type = htonl (GNUNET_BLOCK_TYPE_ANY);
+      sm->anonymity_level = htonl (sc->anonymity);
+      sm->query = sc->requests[sc->keyword_offset].query;
+      msize += sizeof (GNUNET_HashCode) * mbc.put_cnt;
+      GNUNET_CONTAINER_multihashmap_iterate (sc->master_result_map,
+                                            &build_result_set,
+                                            &mbc);
+      sm->header.size = htons (msize);
+      if (sqms != sc->search_request_map_offset)
        {
-         sm[i].header.size = htons (sizeof (struct SearchMessage));
-         sm[i].header.type = htons (GNUNET_MESSAGE_TYPE_FS_START_SEARCH);
-         sm[i].anonymity_level = htonl (sc->anonymity);
-         sm[i].query = sc->requests[i].query;
+         /* more requesting to be done... */
+         schedule_transmit_search_request (sc);
+         return msize;
+       }
+      sc->keyword_offset++;
+      if (sc->uri->data.ksk.keywordCount !=
+         sc->keyword_offset)
+       {
+         /* more requesting to be done... */
+         schedule_transmit_search_request (sc);
+         return msize;
        }
     }
   else
     {
+      GNUNET_assert (GNUNET_FS_uri_test_sks (sc->uri));
       msize = sizeof (struct SearchMessage);
       GNUNET_assert (size >= msize);
-      sm = buf;
-      memset (sm, 0, msize);
-      sm->header.size = htons (sizeof (struct SearchMessage));
-      sm->header.type = htons (GNUNET_MESSAGE_TYPE_FS_START_SEARCH);
+      if (0 != (sc->options & GNUNET_FS_SEARCH_OPTION_LOOPBACK_ONLY))
+       sm->options = htonl (1);
+      else
+       sm->options = htonl (0);      
+      sm->type = htonl (GNUNET_BLOCK_TYPE_FS_SBLOCK);
       sm->anonymity_level = htonl (sc->anonymity);
       sm->target = sc->uri->data.sks.namespace;
       identifier = sc->uri->data.sks.identifier;
       GNUNET_CRYPTO_hash (identifier,
                          strlen (identifier),
+                         &key);
+      GNUNET_CRYPTO_hash (&key,
+                         sizeof (GNUNET_HashCode),
                          &idh);
       GNUNET_CRYPTO_hash_xor (&idh,
                              &sm->target,
                              &sm->query);
+      mbc.put_cnt = (size - msize) / sizeof (GNUNET_HashCode);
+      sqms = GNUNET_CONTAINER_multihashmap_size (sc->master_result_map);
+      mbc.put_cnt = GNUNET_MIN (mbc.put_cnt,
+                               sqms - mbc.skip_cnt);
+      mbc.uri = NULL;
+      if (sc->search_request_map_offset < sqms)
+       GNUNET_assert (mbc.put_cnt > 0);
+      msize += sizeof (GNUNET_HashCode) * mbc.put_cnt;
+      GNUNET_CONTAINER_multihashmap_iterate (sc->master_result_map,
+                                            &build_result_set,
+                                            &mbc);
+      sm->header.size = htons (msize);
+      if (sqms != sc->search_request_map_offset)
+       {
+         /* more requesting to be done... */
+         schedule_transmit_search_request (sc);
+         return msize;
+       }
     }
   GNUNET_CLIENT_receive (sc->client,
                         &receive_results,
@@ -662,6 +1144,34 @@ transmit_search_request (void *cls,
 }
 
 
+/**
+ * Schedule the transmission of the (next) search request
+ * to the service.
+ *
+ * @param sc context for the search
+ */
+static void
+schedule_transmit_search_request (struct GNUNET_FS_SearchContext *sc)
+{
+  size_t size;
+  unsigned int sqms;
+  unsigned int fit;
+
+  size = sizeof (struct SearchMessage);
+  sqms = GNUNET_CONTAINER_multihashmap_size (sc->master_result_map) - sc->search_request_map_offset;  
+  fit = (GNUNET_SERVER_MAX_MESSAGE_SIZE - 1 - size) / sizeof (GNUNET_HashCode);
+  fit = GNUNET_MIN (fit, sqms);
+  size += sizeof (GNUNET_HashCode) * fit;
+  GNUNET_CLIENT_notify_transmit_ready (sc->client,
+                                      size,
+                                       GNUNET_CONSTANTS_SERVICE_TIMEOUT,
+                                      GNUNET_NO,
+                                      &transmit_search_request,
+                                      sc);  
+
+}
+
+
 /**
  * Reconnect to the FS service and transmit
  * our queries NOW.
@@ -675,11 +1185,9 @@ do_reconnect (void *cls,
 {
   struct GNUNET_FS_SearchContext *sc = cls;
   struct GNUNET_CLIENT_Connection *client;
-  size_t size;
-  
   sc->task = GNUNET_SCHEDULER_NO_TASK;
-  client = GNUNET_CLIENT_connect (sc->h->sched,
-                                 "fs",
+  client = GNUNET_CLIENT_connect ("fs",
                                  sc->h->cfg);
   if (NULL == client)
     {
@@ -687,15 +1195,9 @@ do_reconnect (void *cls,
       return;
     }
   sc->client = client;
-  if (GNUNET_FS_uri_test_ksk (sc->uri))
-    size = sizeof (struct SearchMessage) * sc->uri->data.ksk.keywordCount;
-  else
-    size = sizeof (struct SearchMessage);
-  GNUNET_CLIENT_notify_transmit_ready (client,
-                                      size,
-                                       GNUNET_CONSTANTS_SERVICE_TIMEOUT,
-                                      &transmit_search_request,
-                                      sc);  
+  sc->search_request_map_offset = 0;
+  sc->keyword_offset = 0;
+  schedule_transmit_search_request (sc);
 }
 
 
@@ -711,15 +1213,11 @@ try_reconnect (struct GNUNET_FS_SearchContext *sc)
 {
   if (NULL != sc->client)
     {
-      GNUNET_CLIENT_disconnect (sc->client);
+      GNUNET_CLIENT_disconnect (sc->client, GNUNET_NO);
       sc->client = NULL;
     }
   sc->task
-    = GNUNET_SCHEDULER_add_delayed (sc->h->sched,
-                                   GNUNET_NO,
-                                   GNUNET_SCHEDULER_PRIORITY_IDLE,
-                                   GNUNET_SCHEDULER_NO_TASK,
-                                   GNUNET_TIME_UNIT_SECONDS,
+    = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS,
                                    &do_reconnect,
                                    sc);
 }
@@ -732,89 +1230,231 @@ try_reconnect (struct GNUNET_FS_SearchContext *sc)
  * @param uri specifies the search parameters; can be
  *        a KSK URI or an SKS URI.
  * @param anonymity desired level of anonymity
- * @param parent parent search (for namespace update searches)
+ * @param options options for the search
+ * @param cctx initial value for the client context
+ * @param psearch parent search result (for namespace update searches)
  * @return context that can be used to control the search
  */
 static struct GNUNET_FS_SearchContext *
 search_start (struct GNUNET_FS_Handle *h,
              const struct GNUNET_FS_Uri *uri,
              uint32_t anonymity,
-             struct GNUNET_FS_SearchContext *parent)
+             enum GNUNET_FS_SearchOptions options,
+             void *cctx,
+             struct GNUNET_FS_SearchResult *psearch)
 {
   struct GNUNET_FS_SearchContext *sc;
-  struct GNUNET_CLIENT_Connection *client;
   struct GNUNET_FS_ProgressInfo pi;
-  size_t size;
+
+  sc = GNUNET_malloc (sizeof(struct GNUNET_FS_SearchContext));
+  sc->h = h;
+  sc->options = options;
+  sc->uri = GNUNET_FS_uri_dup (uri);
+  sc->anonymity = anonymity;
+  sc->start_time = GNUNET_TIME_absolute_get ();
+  if (psearch != NULL)
+    {
+      sc->psearch_result = psearch;  
+      psearch->update_search = sc;
+    }
+  sc->master_result_map = GNUNET_CONTAINER_multihashmap_create (16);
+  sc->client_info = cctx;
+  if (GNUNET_OK !=
+      GNUNET_FS_search_start_searching_ (sc))
+    {
+      GNUNET_FS_uri_destroy (sc->uri);
+      GNUNET_CONTAINER_multihashmap_destroy (sc->master_result_map);
+      GNUNET_free (sc);      
+      return NULL;
+    }
+  GNUNET_FS_search_sync_ (sc);
+  pi.status = GNUNET_FS_STATUS_SEARCH_START;
+  sc->client_info = GNUNET_FS_search_make_status_ (&pi, sc);
+  return sc;
+}
+
+
+/**
+ * Build the request and actually initiate the search using the
+ * GNUnet FS service.
+ *
+ * @param sc search context
+ * @return GNUNET_OK on success, GNUNET_SYSERR on error
+ */
+int
+GNUNET_FS_search_start_searching_ (struct GNUNET_FS_SearchContext *sc)
+{
   unsigned int i;
   const char *keyword;
   GNUNET_HashCode hc;
   struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded pub;  
   struct GNUNET_CRYPTO_RsaPrivateKey *pk;
 
-  if (GNUNET_FS_uri_test_ksk (uri))
+  GNUNET_assert (NULL == sc->client);
+  if (GNUNET_FS_uri_test_ksk (sc->uri))
     {
-      size = sizeof (struct SearchMessage) * uri->data.ksk.keywordCount;
+      GNUNET_assert (0 != sc->uri->data.ksk.keywordCount);
+      sc->requests = GNUNET_malloc (sizeof (struct SearchRequestEntry) *
+                                   sc->uri->data.ksk.keywordCount);
+      for (i=0;i<sc->uri->data.ksk.keywordCount;i++)
+       {
+         keyword = &sc->uri->data.ksk.keywords[i][1];
+         GNUNET_CRYPTO_hash (keyword, 
+                             strlen (keyword), 
+                             &hc);
+         pk = GNUNET_CRYPTO_rsa_key_create_from_hash (&hc);
+         GNUNET_assert (pk != NULL);
+         GNUNET_CRYPTO_rsa_key_get_public (pk, &pub);
+         GNUNET_CRYPTO_rsa_key_free (pk);
+         GNUNET_CRYPTO_hash (&pub,
+                             sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded), 
+                             &sc->requests[i].query);
+         sc->requests[i].mandatory = (sc->uri->data.ksk.keywords[i][0] == '+');
+         if (sc->requests[i].mandatory)
+           sc->mandatory_count++;
+         sc->requests[i].results = GNUNET_CONTAINER_multihashmap_create (4);
+         GNUNET_CRYPTO_hash (keyword,
+                             strlen (keyword),
+                             &sc->requests[i].key);
+       }
     }
-  else
+  sc->client = GNUNET_CLIENT_connect ("fs",
+                                     sc->h->cfg);
+  if (NULL == sc->client)
+    return GNUNET_SYSERR;
+  schedule_transmit_search_request (sc);
+  return GNUNET_OK;
+}
+
+
+/**
+ * Freeze probes for the given search result.
+ *
+ * @param cls the global FS handle
+ * @param key the key for the search result (unused)
+ * @param value the search result to free
+ * @return GNUNET_OK
+ */
+static int
+search_result_freeze_probes (void *cls,
+                            const GNUNET_HashCode * key,
+                            void *value)
+{
+  struct GNUNET_FS_SearchResult *sr = value;
+
+  if (sr->probe_ctx != NULL)
     {
-      GNUNET_assert (GNUNET_FS_uri_test_sks (uri));
-      size = sizeof (struct SearchMessage);
+      GNUNET_FS_download_stop (sr->probe_ctx, GNUNET_YES);    
+      sr->probe_ctx = NULL;
     }
-  if (size >= GNUNET_SERVER_MAX_MESSAGE_SIZE)
+  if (sr->probe_cancel_task != GNUNET_SCHEDULER_NO_TASK)
     {
-      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
-                 _("Too many keywords specified for a single search."));
-      return NULL;
+      GNUNET_SCHEDULER_cancel (sr->probe_cancel_task);
+      sr->probe_cancel_task = GNUNET_SCHEDULER_NO_TASK;
     }
-  client = GNUNET_CLIENT_connect (h->sched,
-                                 "fs",
-                                 h->cfg);
-  if (NULL == client)
-    return NULL;
-  sc = GNUNET_malloc (sizeof(struct GNUNET_FS_SearchContext));
-  sc->h = h;
-  sc->uri = GNUNET_FS_uri_dup (uri);
-  sc->anonymity = anonymity;
-  sc->start_time = GNUNET_TIME_absolute_get ();
-  sc->client = client;  
-  sc->parent = parent;
-  sc->master_result_map = GNUNET_CONTAINER_multihashmap_create (16);
+  if (sr->update_search != NULL)
+    GNUNET_FS_search_pause (sr->update_search);
+  return GNUNET_OK;
+}
 
-  sc->requests = GNUNET_malloc (sizeof (struct SearchRequestEntry) *
-                               sc->uri->data.ksk.keywordCount);
-  for (i=0;i<sc->uri->data.ksk.keywordCount;i++)
+
+/**
+ * Resume probes for the given search result.
+ *
+ * @param cls the global FS handle
+ * @param key the key for the search result (unused)
+ * @param value the search result to free
+ * @return GNUNET_OK
+ */
+static int
+search_result_resume_probes (void *cls,
+                            const GNUNET_HashCode * key,
+                            void *value)
+{
+  struct GNUNET_FS_SearchResult *sr = value;
+
+  GNUNET_FS_search_start_probe_ (sr);
+  if (sr->update_search != NULL)
+    GNUNET_FS_search_continue (sr->update_search);
+  return GNUNET_OK;
+}
+
+
+/**
+ * Signal suspend and free the given search result.
+ *
+ * @param cls the global FS handle
+ * @param key the key for the search result (unused)
+ * @param value the search result to free
+ * @return GNUNET_OK
+ */
+static int
+search_result_suspend (void *cls,
+                      const GNUNET_HashCode * key,
+                      void *value)
+{
+  struct GNUNET_FS_SearchContext *sc = cls;
+  struct GNUNET_FS_SearchResult *sr = value;
+  struct GNUNET_FS_ProgressInfo pi;
+
+  if (sr->download != NULL)
+    GNUNET_FS_download_signal_suspend_ (sr->download);
+  if (sr->update_search != NULL)
+    GNUNET_FS_search_signal_suspend_ (sr->update_search);
+  pi.status = GNUNET_FS_STATUS_SEARCH_RESULT_SUSPEND;
+  pi.value.search.specifics.result_suspend.cctx = sr->client_info;
+  pi.value.search.specifics.result_suspend.meta = sr->meta;
+  pi.value.search.specifics.result_suspend.uri = sr->uri;
+  sr->client_info = GNUNET_FS_search_make_status_ (&pi, sc);
+  GNUNET_break (NULL == sr->client_info);
+  GNUNET_free_non_null (sr->serialization);
+  GNUNET_FS_uri_destroy (sr->uri);
+  GNUNET_CONTAINER_meta_data_destroy (sr->meta);
+  if (sr->probe_ctx != NULL)
+    GNUNET_FS_download_stop (sr->probe_ctx, GNUNET_YES);    
+  if (sr->probe_cancel_task != GNUNET_SCHEDULER_NO_TASK)
+    GNUNET_SCHEDULER_cancel (sr->probe_cancel_task);
+  GNUNET_free (sr);
+  return GNUNET_OK;
+}
+
+
+/**
+ * Create SUSPEND event for the given search operation
+ * and then clean up our state (without stop signal).
+ *
+ * @param cls the 'struct GNUNET_FS_SearchContext' to signal for
+ */
+void
+GNUNET_FS_search_signal_suspend_ (void *cls)
+{
+  struct GNUNET_FS_SearchContext *sc = cls;
+  struct GNUNET_FS_ProgressInfo pi;
+  unsigned int i;
+
+  GNUNET_FS_end_top (sc->h, sc->top);
+  GNUNET_CONTAINER_multihashmap_iterate (sc->master_result_map,
+                                        &search_result_suspend,
+                                        sc);
+  pi.status = GNUNET_FS_STATUS_SEARCH_SUSPEND;
+  sc->client_info = GNUNET_FS_search_make_status_ (&pi, sc);
+  GNUNET_break (NULL == sc->client_info);
+  if (sc->task != GNUNET_SCHEDULER_NO_TASK)
+    GNUNET_SCHEDULER_cancel (sc->task);
+  if (NULL != sc->client)
+    GNUNET_CLIENT_disconnect (sc->client, GNUNET_NO);
+  GNUNET_CONTAINER_multihashmap_destroy (sc->master_result_map);
+  if (sc->requests != NULL)
     {
-      keyword = &sc->uri->data.ksk.keywords[i][1];
-      GNUNET_CRYPTO_hash (keyword, strlen (keyword), &hc);
-      pk = GNUNET_CRYPTO_rsa_key_create_from_hash (&hc);
-      GNUNET_CRYPTO_rsa_key_get_public (pk, &pub);
-      GNUNET_CRYPTO_rsa_key_free (pk);
-      GNUNET_CRYPTO_hash (&pub,
-                         sizeof (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded), 
-                         &sc->requests[i].query);
-      sc->requests[i].mandatory = (sc->uri->data.ksk.keywords[i][0] == '+');
-      if (sc->requests[i].mandatory)
-       sc->mandatory_count++;
-      sc->requests[i].results = GNUNET_CONTAINER_multihashmap_create (4);
-      GNUNET_CRYPTO_hash (keyword,
-                         strlen (keyword),
-                         &sc->requests[i].key);
-    }
-  if (NULL != parent)
-    {
-      // FIXME: need to track children
-      // in parent in case parent is stopped!
+      GNUNET_assert (GNUNET_FS_uri_test_ksk (sc->uri));
+      for (i=0;i<sc->uri->data.ksk.keywordCount;i++)
+       GNUNET_CONTAINER_multihashmap_destroy (sc->requests[i].results);
     }
-  pi.status = GNUNET_FS_STATUS_SEARCH_START;
-  make_search_status (&pi, sc);
-  sc->client_info = h->upcb (h->upcb_cls,
-                            &pi);
-  GNUNET_CLIENT_notify_transmit_ready (client,
-                                      size,
-                                       GNUNET_CONSTANTS_SERVICE_TIMEOUT,
-                                      &transmit_search_request,
-                                      sc);  
-  return sc;
+  GNUNET_free_non_null (sc->requests);
+  GNUNET_free_non_null (sc->emsg);
+  GNUNET_FS_uri_destroy (sc->uri);
+  GNUNET_free_non_null (sc->serialization);
+  GNUNET_free (sc);
 }
 
 
@@ -825,14 +1465,23 @@ search_start (struct GNUNET_FS_Handle *h,
  * @param uri specifies the search parameters; can be
  *        a KSK URI or an SKS URI.
  * @param anonymity desired level of anonymity
+ * @param options options for the search
+ * @param cctx initial value for the client context
  * @return context that can be used to control the search
  */
 struct GNUNET_FS_SearchContext *
 GNUNET_FS_search_start (struct GNUNET_FS_Handle *h,
                        const struct GNUNET_FS_Uri *uri,
-                       uint32_t anonymity)
+                       uint32_t anonymity,
+                       enum GNUNET_FS_SearchOptions options,
+                       void *cctx)
 {
-  return search_start (h, uri, anonymity, NULL);
+  struct GNUNET_FS_SearchContext *ret;
+  ret = search_start (h, uri, anonymity, options, cctx, NULL);
+  if (ret == NULL)
+    return NULL;
+  ret->top = GNUNET_FS_make_top (h, &GNUNET_FS_search_signal_suspend_, ret);
+  return ret;
 }
 
 
@@ -847,18 +1496,17 @@ GNUNET_FS_search_pause (struct GNUNET_FS_SearchContext *sc)
   struct GNUNET_FS_ProgressInfo pi;
 
   if (sc->task != GNUNET_SCHEDULER_NO_TASK)
-    GNUNET_SCHEDULER_cancel (sc->h->sched,
-                            sc->task);
+    GNUNET_SCHEDULER_cancel (sc->task);
   sc->task = GNUNET_SCHEDULER_NO_TASK;
   if (NULL != sc->client)
-    GNUNET_CLIENT_disconnect (sc->client);
+    GNUNET_CLIENT_disconnect (sc->client, GNUNET_NO);
   sc->client = NULL;
-  // FIXME: make persistent!
-  // FIXME: should this freeze all active probes?
+  GNUNET_FS_search_sync_ (sc);
+  GNUNET_CONTAINER_multihashmap_iterate (sc->master_result_map,
+                                        &search_result_freeze_probes,
+                                        sc);
   pi.status = GNUNET_FS_STATUS_SEARCH_PAUSED;
-  make_search_status (&pi, sc);
-  sc->client_info = sc->h->upcb (sc->h->upcb_cls,
-                                &pi);
+  sc->client_info = GNUNET_FS_search_make_status_ (&pi, sc);
 }
 
 
@@ -875,11 +1523,12 @@ GNUNET_FS_search_continue (struct GNUNET_FS_SearchContext *sc)
   GNUNET_assert (sc->client == NULL);
   GNUNET_assert (sc->task == GNUNET_SCHEDULER_NO_TASK);
   do_reconnect (sc, NULL);
-  // FIXME: make persistent!
+  GNUNET_FS_search_sync_ (sc);
   pi.status = GNUNET_FS_STATUS_SEARCH_CONTINUED;
-  make_search_status (&pi, sc);
-  sc->client_info = sc->h->upcb (sc->h->upcb_cls,
-                                &pi);
+  sc->client_info = GNUNET_FS_search_make_status_ (&pi, sc);
+  GNUNET_CONTAINER_multihashmap_iterate (sc->master_result_map,
+                                        &search_result_resume_probes,
+                                        sc);
 }
 
 
@@ -897,35 +1546,47 @@ search_result_free (void *cls,
                    void *value)
 {
   struct GNUNET_FS_SearchContext *sc = cls;
-  struct GNUNET_FS_Handle *h = sc->h;
-  struct SearchResult *sr = value;
+  struct GNUNET_FS_SearchResult *sr = value;
   struct GNUNET_FS_ProgressInfo pi;
 
+  if (NULL != sr->download)
+    {
+      sr->download->search = NULL;
+      sr->download->top = GNUNET_FS_make_top (sr->download->h,
+                                             &GNUNET_FS_download_signal_suspend_,
+                                             sr->download);
+      if (NULL != sr->download->serialization)
+       {
+         GNUNET_FS_remove_sync_file_ (sc->h,
+                                      GNUNET_FS_SYNC_PATH_CHILD_DOWNLOAD,
+                                      sr->download->serialization);
+         GNUNET_free (sr->download->serialization);
+         sr->download->serialization = NULL;
+       }
+      pi.status = GNUNET_FS_STATUS_DOWNLOAD_LOST_PARENT;
+      GNUNET_FS_download_make_status_ (&pi,
+                                      sr->download);      
+      GNUNET_FS_download_sync_ (sr->download);
+      sr->download = NULL;     
+    }
+  if (NULL != sr->update_search)
+    {
+      GNUNET_FS_search_stop (sr->update_search);
+      GNUNET_assert (sr->update_search == NULL);
+    }
   pi.status = GNUNET_FS_STATUS_SEARCH_RESULT_STOPPED;
-  make_search_status (&pi, sc);
   pi.value.search.specifics.result_stopped.cctx = sr->client_info;
   pi.value.search.specifics.result_stopped.meta = sr->meta;
   pi.value.search.specifics.result_stopped.uri = sr->uri;
-  sr->client_info = h->upcb (h->upcb_cls,
-                            &pi);
+  sr->client_info = GNUNET_FS_search_make_status_ (&pi, sc);
   GNUNET_break (NULL == sr->client_info);
-  
+  GNUNET_free_non_null (sr->serialization);
   GNUNET_FS_uri_destroy (sr->uri);
   GNUNET_CONTAINER_meta_data_destroy (sr->meta);
   if (sr->probe_ctx != NULL)
-    {
-      GNUNET_FS_file_download_stop (sr->probe_ctx, GNUNET_YES);
-      h->active_probes--;
-      /* FIXME: trigger starting of new
-        probes here!? Maybe not -- could
-        cause new probes to be immediately
-        stopped again... */
-    }
+    GNUNET_FS_download_stop (sr->probe_ctx, GNUNET_YES);    
   if (sr->probe_cancel_task != GNUNET_SCHEDULER_NO_TASK)
-    {
-      GNUNET_SCHEDULER_cancel (h->sched,
-                              sr->probe_cancel_task);
-    }
+    GNUNET_SCHEDULER_cancel (sr->probe_cancel_task);
   GNUNET_free (sr);
   return GNUNET_OK;
 }
@@ -942,29 +1603,43 @@ GNUNET_FS_search_stop (struct GNUNET_FS_SearchContext *sc)
   struct GNUNET_FS_ProgressInfo pi;
   unsigned int i;
 
-  // FIXME: make un-persistent!
-  if (NULL != sc->parent)
-    {
-      // FIXME: need to untrack sc
-      // in parent!
-    }
+  if (sc->top != NULL)
+    GNUNET_FS_end_top (sc->h, sc->top);
+  if (sc->psearch_result != NULL)
+    sc->psearch_result->update_search = NULL;
   GNUNET_CONTAINER_multihashmap_iterate (sc->master_result_map,
                                         &search_result_free,
                                         sc);
+  if (sc->serialization != NULL)
+    {
+      GNUNET_FS_remove_sync_file_ (sc->h,
+                                  (sc->psearch_result != NULL)  
+                                  ? GNUNET_FS_SYNC_PATH_CHILD_SEARCH 
+                                  : GNUNET_FS_SYNC_PATH_MASTER_SEARCH,
+                                  sc->serialization);
+      GNUNET_FS_remove_sync_dir_ (sc->h,
+                                 (sc->psearch_result != NULL)  
+                                 ? GNUNET_FS_SYNC_PATH_CHILD_SEARCH 
+                                 : GNUNET_FS_SYNC_PATH_MASTER_SEARCH,
+                                 sc->serialization);
+      GNUNET_free (sc->serialization);
+    }
   pi.status = GNUNET_FS_STATUS_SEARCH_STOPPED;
-  make_search_status (&pi, sc);
-  sc->client_info = sc->h->upcb (sc->h->upcb_cls,
-                                &pi);
+  sc->client_info = GNUNET_FS_search_make_status_ (&pi, sc);
   GNUNET_break (NULL == sc->client_info);
   if (sc->task != GNUNET_SCHEDULER_NO_TASK)
-    GNUNET_SCHEDULER_cancel (sc->h->sched,
-                            sc->task);
+    GNUNET_SCHEDULER_cancel (sc->task);
   if (NULL != sc->client)
-    GNUNET_CLIENT_disconnect (sc->client);
+    GNUNET_CLIENT_disconnect (sc->client, GNUNET_NO);
   GNUNET_CONTAINER_multihashmap_destroy (sc->master_result_map);
-  for (i=0;i<sc->uri->data.ksk.keywordCount;i++)
-    GNUNET_CONTAINER_multihashmap_destroy (sc->requests[i].results);
+  if (sc->requests != NULL)
+    {
+      GNUNET_assert (GNUNET_FS_uri_test_ksk (sc->uri));
+      for (i=0;i<sc->uri->data.ksk.keywordCount;i++)
+       GNUNET_CONTAINER_multihashmap_destroy (sc->requests[i].results);
+    }
   GNUNET_free_non_null (sc->requests);
+  GNUNET_free_non_null (sc->emsg);
   GNUNET_FS_uri_destroy (sc->uri);
   GNUNET_free (sc);
 }