fs_search.c

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/*
     This file is part of GNUnet.
     Copyright (C) 2001-2014 GNUnet e.V.

     GNUnet is free software: you can redistribute it and/or modify it
     under the terms of the GNU Affero General Public License as published
     by the Free Software Foundation, either version 3 of the License,
     or (at your option) any later version.

     GNUnet is distributed in the hope that it will be useful, but
     WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Affero General Public License for more details.

     You should have received a copy of the GNU Affero General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.

     SPDX-License-Identifier: AGPL3.0-or-later
 */
#include "platform.h"
#include "gnunet_constants.h"
#include "gnunet_fs_service.h"
#include "gnunet_protocols.h"
#include "fs_api.h"
#include "fs_publish_ublock.h"


#define AVAILABILITY_TRIALS_MAX 8

void *
GNUNET_FS_search_make_status_(struct GNUNET_FS_ProgressInfo *pi,
                              struct GNUNET_FS_Handle *h,
                              struct GNUNET_FS_SearchContext *sc)
{
  void *ret;

  pi->value.search.sc = sc;
  pi->value.search.cctx = (NULL != sc) ? sc->client_info : NULL;
  pi->value.search.pctx =
    ((NULL == sc) || (NULL == sc->psearch_result))
    ? NULL
    : sc->psearch_result->client_info;
  pi->value.search.query = (NULL != sc) ? sc->uri : NULL;
  pi->value.search.duration = (NULL != sc)
                              ? GNUNET_TIME_absolute_get_duration(sc->start_time)
                              : GNUNET_TIME_UNIT_ZERO;
  pi->value.search.anonymity = (NULL != sc) ? sc->anonymity : 0;
  pi->fsh = h;
  ret = h->upcb(h->upcb_cls, pi);
  return ret;
}


static int
test_result_present(void *cls,
                    const struct GNUNET_HashCode * key,
                    void *value)
{
  const struct GNUNET_FS_Uri *uri = cls;
  struct GNUNET_FS_SearchResult *sr = value;

  if (GNUNET_FS_uri_test_equal(uri, sr->uri))
    return GNUNET_SYSERR;
  return GNUNET_OK;
}


static void
notify_client_chk_result(struct GNUNET_FS_SearchContext *sc,
                         struct GNUNET_FS_SearchResult *sr)
{
  struct GNUNET_FS_ProgressInfo pi;

  pi.status = GNUNET_FS_STATUS_SEARCH_RESULT;
  pi.value.search.specifics.result.meta = sr->meta;
  pi.value.search.specifics.result.uri = sr->uri;
  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->h, sc);
}


static void
notify_client_chk_update(struct GNUNET_FS_SearchContext *sc,
                         struct GNUNET_FS_SearchResult *sr)
{
  struct GNUNET_FS_ProgressInfo pi;

  pi.status = GNUNET_FS_STATUS_SEARCH_UPDATE;
  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 =
    2 * sr->availability_success - sr->availability_trials;
  pi.value.search.specifics.update.availability_certainty =
    sr->availability_trials;
  pi.value.search.specifics.update.applicability_rank = sr->optional_support;
  pi.value.search.specifics.update.current_probe_time
    = GNUNET_TIME_absolute_get_duration(sr->probe_active_time);
  sr->client_info = GNUNET_FS_search_make_status_(&pi, sc->h, sc);
}


struct GetResultContext {
  const struct GNUNET_FS_Uri *uri;

  struct GNUNET_FS_SearchResult *sr;
};


static int
get_result_present(void *cls,
                   const struct GNUNET_HashCode *key,
                   void *value)
{
  struct GetResultContext *grc = cls;
  struct GNUNET_FS_SearchResult *sr = value;

  if (GNUNET_FS_uri_test_equal(grc->uri, sr->uri))
    grc->sr = sr;
  return GNUNET_OK;
}


static void
signal_probe_result(struct GNUNET_FS_SearchResult *sr)
{
  struct GNUNET_FS_ProgressInfo pi;

  pi.status = GNUNET_FS_STATUS_SEARCH_UPDATE;
  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
    = 2 * sr->availability_success - sr->availability_trials;
  pi.value.search.specifics.update.availability_certainty
    = sr->availability_trials;
  pi.value.search.specifics.update.applicability_rank = sr->optional_support;
  pi.value.search.specifics.update.current_probe_time
    = GNUNET_TIME_absolute_get_duration(sr->probe_active_time);
  sr->client_info = GNUNET_FS_search_make_status_(&pi, sr->h, sr->sc);
  GNUNET_FS_search_start_probe_(sr);
}


static void
probe_failure_handler(void *cls)
{
  struct GNUNET_FS_SearchResult *sr = cls;

  sr->probe_cancel_task = NULL;
  sr->availability_trials++;
  GNUNET_FS_download_stop(sr->probe_ctx, GNUNET_YES);
  sr->probe_ctx = NULL;
  GNUNET_FS_stop_probe_ping_task_(sr);
  GNUNET_FS_search_result_sync_(sr);
  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
             "Probe #%u for search result %p failed\n",
             sr->availability_trials,
             sr);
  signal_probe_result(sr);
}


static void
probe_success_handler(void *cls)
{
  struct GNUNET_FS_SearchResult *sr = cls;

  sr->probe_cancel_task = NULL;
  sr->availability_trials++;
  sr->availability_success++;
  GNUNET_FS_download_stop(sr->probe_ctx, GNUNET_YES);
  sr->probe_ctx = NULL;
  GNUNET_FS_stop_probe_ping_task_(sr);
  GNUNET_FS_search_result_sync_(sr);
  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
             "Probe #%u for search result %p succeeded\n",
             sr->availability_trials,
             sr);
  signal_probe_result(sr);
}


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 (NULL != sr->probe_cancel_task)
        {
          GNUNET_SCHEDULER_cancel(sr->probe_cancel_task);
          sr->probe_cancel_task = NULL;
        }
      sr->probe_cancel_task =
        GNUNET_SCHEDULER_add_delayed(sr->remaining_probe_time,
                                     &probe_failure_handler, sr);
      break;

    case GNUNET_FS_STATUS_DOWNLOAD_COMPLETED:
      if (NULL != sr->probe_cancel_task)
        {
          GNUNET_SCHEDULER_cancel(sr->probe_cancel_task);
          sr->probe_cancel_task = NULL;
        }
      sr->probe_cancel_task =
        GNUNET_SCHEDULER_add_now(&probe_success_handler, sr);
      break;

    case GNUNET_FS_STATUS_DOWNLOAD_STOPPED:
      if (NULL != sr->probe_cancel_task)
        {
          GNUNET_SCHEDULER_cancel(sr->probe_cancel_task);
          sr->probe_cancel_task = NULL;
        }
      sr = NULL;
      break;

    case GNUNET_FS_STATUS_DOWNLOAD_ACTIVE:
      if (NULL == sr->probe_cancel_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 (NULL != sr->probe_cancel_task)
        {
          GNUNET_SCHEDULER_cancel(sr->probe_cancel_task);
          sr->probe_cancel_task = NULL;
        }
      dur = GNUNET_TIME_absolute_get_duration(sr->probe_active_time);
      sr->remaining_probe_time =
        GNUNET_TIME_relative_subtract(sr->remaining_probe_time, dur);
      if (0 == sr->remaining_probe_time.rel_value_us)
        sr->probe_cancel_task =
          GNUNET_SCHEDULER_add_now(&probe_failure_handler, sr);
      GNUNET_FS_search_result_sync_(sr);
      break;

    default:
      GNUNET_break(0);
      return NULL;
    }
  return sr;
}


static void
probe_ping_task_cb(void *cls)
{
  struct GNUNET_FS_Handle *h = cls;
  struct GNUNET_FS_SearchResult *sr;

  for (sr = h->probes_head; NULL != sr; sr = sr->next)
    if (NULL != sr->probe_ctx->mq)
      signal_probe_result(sr);
  h->probe_ping_task
    = GNUNET_SCHEDULER_add_delayed(GNUNET_FS_PROBE_UPDATE_FREQUENCY,
                                   &probe_ping_task_cb,
                                   h);
}


static void
start_probe_ping_task(struct GNUNET_FS_SearchResult *sr)
{
  struct GNUNET_FS_Handle *h = sr->h;

  GNUNET_CONTAINER_DLL_insert(h->probes_head,
                              h->probes_tail,
                              sr);
  if (NULL == h->probe_ping_task)
    h->probe_ping_task
      = GNUNET_SCHEDULER_add_now(&probe_ping_task_cb,
                                 h);
}


void
GNUNET_FS_stop_probe_ping_task_(struct GNUNET_FS_SearchResult *sr)
{
  struct GNUNET_FS_Handle *h = sr->h;

  GNUNET_CONTAINER_DLL_remove(h->probes_head,
                              h->probes_tail,
                              sr);
  if (NULL == h->probes_head)
    {
      GNUNET_SCHEDULER_cancel(h->probe_ping_task);
      h->probe_ping_task = NULL;
    }
}


void
GNUNET_FS_search_start_probe_(struct GNUNET_FS_SearchResult *sr)
{
  uint64_t off;
  uint64_t len;

  if (NULL != sr->probe_ctx)
    return;
  if (NULL != sr->download)
    return;
  if (0 == (sr->h->flags & GNUNET_FS_FLAGS_DO_PROBES))
    return;
  if (sr->availability_trials > AVAILABILITY_TRIALS_MAX)
    return;
  if ((GNUNET_FS_URI_CHK != sr->uri->type) && (GNUNET_FS_URI_LOC != sr->uri->type))
    return;
  len = GNUNET_FS_uri_chk_get_file_size(sr->uri);
  if (0 == len)
    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;
  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
             "Starting probe #%u (at offset %llu) for search result %p\n",
             sr->availability_trials + 1,
             (unsigned long long)off,
             sr);
  sr->remaining_probe_time =
    GNUNET_TIME_relative_saturating_multiply(sr->h->avg_block_latency,
                                             2 * (1 + sr->availability_trials));
  sr->probe_ctx =
    GNUNET_FS_download_start(sr->h, sr->uri, sr->meta, NULL, NULL, off,
                             len, sr->anonymity,
                             GNUNET_FS_DOWNLOAD_NO_TEMPORARIES |
                             GNUNET_FS_DOWNLOAD_IS_PROBE, sr, NULL);
  start_probe_ping_task(sr);
}


struct GNUNET_FS_SearchResult *
GNUNET_FS_probe(struct GNUNET_FS_Handle *h,
                const struct GNUNET_FS_Uri *uri,
                const struct GNUNET_CONTAINER_MetaData *meta,
                void *client_info,
                uint32_t anonymity)
{
  struct GNUNET_FS_SearchResult *sr;

  GNUNET_assert(NULL != h);
  GNUNET_assert(NULL != uri);
  sr = GNUNET_new(struct GNUNET_FS_SearchResult);
  sr->h = h;
  sr->uri = GNUNET_FS_uri_dup(uri);
  sr->meta = GNUNET_CONTAINER_meta_data_duplicate(meta);
  sr->client_info = client_info;
  sr->anonymity = anonymity;
  GNUNET_FS_search_start_probe_(sr);
  return sr;
}


static void
GNUNET_FS_search_stop_probe_(struct GNUNET_FS_SearchResult *sr)
{
  if (NULL != sr->probe_ctx)
    {
      GNUNET_FS_download_stop(sr->probe_ctx, GNUNET_YES);
      sr->probe_ctx = NULL;
      GNUNET_FS_stop_probe_ping_task_(sr);
    }
  if (NULL != sr->probe_cancel_task)
    {
      GNUNET_SCHEDULER_cancel(sr->probe_cancel_task);
      sr->probe_cancel_task = NULL;
    }
}


void *
GNUNET_FS_probe_stop(struct GNUNET_FS_SearchResult *sr)
{
  void *client_info;

  GNUNET_assert(NULL == sr->sc);
  GNUNET_FS_search_stop_probe_(sr);
  GNUNET_FS_uri_destroy(sr->uri);
  GNUNET_CONTAINER_meta_data_destroy(sr->meta);
  client_info = sr->client_info;
  GNUNET_free(sr);
  return client_info;
}


static void
process_ksk_result(struct GNUNET_FS_SearchContext *sc,
                   struct SearchRequestEntry *ent,
                   const struct GNUNET_FS_Uri *uri,
                   const struct GNUNET_CONTAINER_MetaData *meta)
{
  struct GNUNET_HashCode key;
  struct GNUNET_FS_SearchResult *sr;
  struct GetResultContext grc;
  int is_new;
  unsigned int koff;

  /* check if new */
  GNUNET_assert(NULL != sc);
  if (GNUNET_OK !=
      GNUNET_FS_uri_to_key(uri,
                           &key))
    {
      GNUNET_break_op(0);
      return;
    }
  if (GNUNET_SYSERR ==
      GNUNET_CONTAINER_multihashmap_get_multiple(ent->results,
                                                 &key,
                                                 &test_result_present,
                                                 (void *)uri))
    return;                     /* duplicate result */
  /* try to find search result in master map */
  grc.sr = NULL;
  grc.uri = uri;
  GNUNET_CONTAINER_multihashmap_get_multiple(sc->master_result_map,
                                             &key,
                                             &get_result_present, &grc);
  sr = grc.sr;
  is_new = (NULL == sr) || (sr->mandatory_missing > 0);
  if (NULL == sr)
    {
      sr = GNUNET_new(struct GNUNET_FS_SearchResult);
      sr->h = sc->h;
      sr->sc = sc;
      sr->anonymity = sc->anonymity;
      sr->uri = GNUNET_FS_uri_dup(uri);
      sr->meta = GNUNET_CONTAINER_meta_data_duplicate(meta);
      sr->mandatory_missing = sc->mandatory_count;
      sr->key = key;
      sr->keyword_bitmap = GNUNET_malloc((sc->uri->data.ksk.keywordCount + 7) / 8); /* round up, count bits */
      GNUNET_CONTAINER_multihashmap_put(sc->master_result_map, &key, sr,
                                        GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
    }
  else
    {
      GNUNET_CONTAINER_meta_data_merge(sr->meta, meta);
    }
  GNUNET_break(GNUNET_OK ==
               GNUNET_CONTAINER_multihashmap_put(ent->results,
                                                 &sr->key,
                                                 sr,
                                                 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));

  koff = ent - sc->requests;
  GNUNET_assert((ent >= sc->requests) &&
                (koff < sc->uri->data.ksk.keywordCount));
  sr->keyword_bitmap[koff / 8] |= (1 << (koff % 8));
  /* check if mandatory satisfied */
  if (1 <= GNUNET_CONTAINER_multihashmap_size(ent->results))
    {
      if (ent->mandatory)
        {
          GNUNET_break(sr->mandatory_missing > 0);
          sr->mandatory_missing--;
        }
      else
        {
          sr->optional_support++;
        }
    }
  if (0 != sr->mandatory_missing)
    {
      GNUNET_break(NULL == sr->client_info);
      return;
    }
  if (is_new)
    notify_client_chk_result(sc, sr);
  else
    notify_client_chk_update(sc, sr);
  GNUNET_FS_search_result_sync_(sr);
  GNUNET_FS_search_start_probe_(sr);
}


static struct GNUNET_FS_SearchContext *
search_start(struct GNUNET_FS_Handle *h,
             const struct GNUNET_FS_Uri *uri,
             uint32_t anonymity,
             enum GNUNET_FS_SearchOptions options,
             void *cctx,
             struct GNUNET_FS_SearchResult *psearch);


static void
process_sks_result(struct GNUNET_FS_SearchContext *sc,
                   const char *id_update,
                   const struct GNUNET_FS_Uri *uri,
                   const struct GNUNET_CONTAINER_MetaData *meta)
{
  struct GNUNET_FS_Uri uu;
  struct GNUNET_HashCode key;
  struct GNUNET_FS_SearchResult *sr;

  /* check if new */
  GNUNET_assert(NULL != sc);
  if (GNUNET_OK !=
      GNUNET_FS_uri_to_key(uri,
                           &key))
    {
      GNUNET_break(0);
      return;
    }
  GNUNET_CRYPTO_hash_xor(&uri->data.chk.chk.key,
                         &uri->data.chk.chk.query,
                         &key);
  if (GNUNET_SYSERR ==
      GNUNET_CONTAINER_multihashmap_get_multiple(sc->master_result_map, &key,
                                                 &test_result_present,
                                                 (void *)uri))
    return;                     /* duplicate result */
  sr = GNUNET_new(struct GNUNET_FS_SearchResult);
  sr->h = sc->h;
  sr->sc = sc;
  sr->anonymity = sc->anonymity;
  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);
  GNUNET_FS_search_result_sync_(sr);
  GNUNET_FS_search_start_probe_(sr);
  /* notify client */
  if (0 == sr->mandatory_missing)
    notify_client_chk_result(sc, sr);
  else
    GNUNET_break(NULL == sr->client_info);
  /* search for updates */
  if (0 == strlen(id_update))
    return;                     /* no updates */
  uu.type = GNUNET_FS_URI_SKS;
  uu.data.sks.ns = sc->uri->data.sks.ns;
  uu.data.sks.identifier = GNUNET_strdup(id_update);
  (void)search_start(sc->h, &uu, sc->anonymity, sc->options, NULL, sr);
  GNUNET_free(uu.data.sks.identifier);
}


static int
decrypt_block_with_keyword(const struct GNUNET_FS_SearchContext *sc,
                           const struct GNUNET_CRYPTO_EcdsaPublicKey *dpub,
                           const void *edata,
                           size_t edata_size,
                           char *data)
{
  const struct GNUNET_CRYPTO_EcdsaPrivateKey *anon;
  struct GNUNET_CRYPTO_EcdsaPublicKey anon_pub;
  unsigned int i;

  /* find key */
  for (i = 0; i < sc->uri->data.ksk.keywordCount; i++)
    if (0 == memcmp(dpub,
                    &sc->requests[i].dpub,
                    sizeof(struct GNUNET_CRYPTO_EcdsaPublicKey)))
      break;
  if (i == sc->uri->data.ksk.keywordCount)
    {
      /* oops, does not match any of our keywords!? */
      GNUNET_break(0);
      return GNUNET_SYSERR;
    }
  /* decrypt */
  anon = GNUNET_CRYPTO_ecdsa_key_get_anonymous();
  GNUNET_CRYPTO_ecdsa_key_get_public(anon, &anon_pub);
  GNUNET_FS_ublock_decrypt_(edata, edata_size,
                            &anon_pub,
                            sc->requests[i].keyword,
                            data);
  return i;
}


static void
process_kblock(struct GNUNET_FS_SearchContext *sc,
               const struct UBlock *ub,
               size_t size)
{
  size_t j;
  char pt[size - sizeof(struct UBlock)];
  const char *eos;
  struct GNUNET_CONTAINER_MetaData *meta;
  struct GNUNET_FS_Uri *uri;
  char *emsg;
  int i;

  if (-1 == (i = decrypt_block_with_keyword(sc,
                                            &ub->verification_key,
                                            &ub[1],
                                            size - sizeof(struct UBlock),
                                            pt)))
    return;
  /* parse; pt[0] is just '\0', so we skip over that */
  eos = memchr(&pt[1], '\0', sizeof(pt) - 1);
  if (NULL == eos)
    {
      GNUNET_break_op(0);
      return;
    }
  if (NULL == (uri = GNUNET_FS_uri_parse(&pt[1], &emsg)))
    {
      if (GNUNET_FS_VERSION > 0x00090400)
        {
          /* we broke this in 0x00090300, so don't bitch
             too loudly just one version up... */
          GNUNET_break_op(0);     /* ublock malformed */
          GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
                     _("Failed to parse URI `%s': %s\n"),
                     &pt[1],
                     emsg);
        }
      GNUNET_free_non_null(emsg);
      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 (NULL == meta)
    {
      GNUNET_break_op(0);       /* ublock malformed */
      GNUNET_FS_uri_destroy(uri);
      return;
    }
  process_ksk_result(sc,
                     &sc->requests[i],
                     uri,
                     meta);

  /* clean up */
  GNUNET_CONTAINER_meta_data_destroy(meta);
  GNUNET_FS_uri_destroy(uri);
}


static void
process_sblock(struct GNUNET_FS_SearchContext *sc,
               const struct UBlock *ub,
               size_t size)
{
  size_t len = size - sizeof(struct UBlock);
  char pt[len];
  struct GNUNET_FS_Uri *uri;
  struct GNUNET_CONTAINER_MetaData *meta;
  const char *id;
  const char *uris;
  size_t off;
  char *emsg;

  GNUNET_FS_ublock_decrypt_(&ub[1], len,
                            &sc->uri->data.sks.ns,
                            sc->uri->data.sks.identifier,
                            pt);
  /* parse */
  if (0 == (off = GNUNET_STRINGS_buffer_tokenize(pt, len, 2, &id, &uris)))
    {
      GNUNET_break_op(0);       /* ublock malformed */
      return;
    }
  if (NULL == (meta = GNUNET_CONTAINER_meta_data_deserialize(&pt[off], len - off)))
    {
      GNUNET_break_op(0);       /* ublock malformed */
      return;
    }
  if (NULL == (uri = GNUNET_FS_uri_parse(uris, &emsg)))
    {
      GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
                 _("Failed to parse URI `%s': %s\n"),
                 uris, emsg);
      GNUNET_break_op(0);       /* ublock malformed */
      GNUNET_free_non_null(emsg);
      GNUNET_CONTAINER_meta_data_destroy(meta);
      return;
    }
  /* process */
  process_sks_result(sc, id, uri, meta);
  /* clean up */
  GNUNET_FS_uri_destroy(uri);
  GNUNET_CONTAINER_meta_data_destroy(meta);
}


static void
try_reconnect(struct GNUNET_FS_SearchContext *sc);


static int
check_result(void *cls,
             const struct ClientPutMessage *cm)
{
  /* payload of any variable size is OK */
  return GNUNET_OK;
}


static void
handle_result(void *cls,
              const struct ClientPutMessage *cm)
{
  struct GNUNET_FS_SearchContext *sc = cls;
  uint16_t msize = ntohs(cm->header.size) - sizeof(*cm);
  enum GNUNET_BLOCK_Type type = ntohl(cm->type);

  if (GNUNET_TIME_absolute_get_duration(GNUNET_TIME_absolute_ntoh(cm->expiration)).rel_value_us > 0)
    {
      GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
                 "Result received has already expired.\n");
      return;                   /* result expired */
    }
  switch (type)
    {
    case GNUNET_BLOCK_TYPE_FS_UBLOCK:
      if (GNUNET_FS_URI_SKS == sc->uri->type)
        process_sblock(sc,
                       (const struct UBlock *)&cm[1],
                       msize);
      else
        process_kblock(sc,
                       (const struct UBlock *)&cm[1],
                       msize);
      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:
      GNUNET_log(GNUNET_ERROR_TYPE_WARNING,
                 _("Got result with unknown block type `%d', ignoring"),
                 type);
      break;
    }
}


static void
schedule_transmit_search_request(struct GNUNET_FS_SearchContext *sc);


struct MessageBuilderContext {
  unsigned int put_cnt;

  unsigned int skip_cnt;

  struct GNUNET_HashCode *xoff;

  struct GNUNET_FS_SearchContext *sc;

  unsigned int keyword_offset;
};


static int
build_result_set(void *cls,
                 const struct GNUNET_HashCode *key,
                 void *value)
{
  struct MessageBuilderContext *mbc = cls;
  struct GNUNET_FS_SearchResult *sr = value;

  if ((NULL != sr->keyword_bitmap) &&
      (0 == (sr->keyword_bitmap[mbc->keyword_offset / 8] & (1 << (mbc->keyword_offset % 8)))))
    return GNUNET_OK; /* have no match for this keyword yet */
  if (mbc->skip_cnt > 0)
    {
      mbc->skip_cnt--;
      return GNUNET_OK;
    }
  if (0 == mbc->put_cnt)
    return GNUNET_SYSERR;
  mbc->xoff[--mbc->put_cnt] = *key;

  return GNUNET_OK;
}


static int
find_result_set(void *cls,
                const struct GNUNET_HashCode *key,
                void *value)
{
  struct MessageBuilderContext *mbc = cls;
  struct GNUNET_FS_SearchResult *sr = value;

  if ((NULL != sr->keyword_bitmap) &&
      (0 == (sr->keyword_bitmap[mbc->keyword_offset / 8] & (1 << (mbc->keyword_offset % 8)))))
    return GNUNET_OK; /* have no match for this keyword yet */
  mbc->put_cnt++;
  return GNUNET_OK;
}


static void
schedule_transmit_search_request(struct GNUNET_FS_SearchContext *sc)
{
  struct MessageBuilderContext mbc;
  struct GNUNET_MQ_Envelope *env;
  struct SearchMessage *sm;
  struct GNUNET_CRYPTO_EcdsaPublicKey dpub;
  unsigned int total_seen_results; /* total number of result hashes to send */
  uint32_t options;
  unsigned int left;
  unsigned int todo;
  unsigned int fit;
  unsigned int search_request_map_offset;
  unsigned int keyword_offset;
  int first_call;

  memset(&mbc, 0, sizeof(mbc));
  mbc.sc = sc;
  if (GNUNET_FS_uri_test_ksk(sc->uri))
    {
      /* This will calculate the result set size ONLY for
         "keyword_offset == 0", so we will have to recalculate
         it for the other keywords later! */
      GNUNET_CONTAINER_multihashmap_iterate(sc->master_result_map,
                                            &find_result_set,
                                            &mbc);
      total_seen_results = mbc.put_cnt;
    }
  else
    {
      total_seen_results
        = GNUNET_CONTAINER_multihashmap_size(sc->master_result_map);
    }
  search_request_map_offset = 0;
  keyword_offset = 0;
  first_call = GNUNET_YES;
  while ((0 != (left =
                  (total_seen_results - search_request_map_offset))) ||
         (GNUNET_YES == first_call))
    {
      first_call = GNUNET_NO;
      options = SEARCH_MESSAGE_OPTION_NONE;
      if (0 != (sc->options & GNUNET_FS_SEARCH_OPTION_LOOPBACK_ONLY))
        options |= SEARCH_MESSAGE_OPTION_LOOPBACK_ONLY;

      fit = (GNUNET_MAX_MESSAGE_SIZE - 1 - sizeof(*sm)) / sizeof(struct GNUNET_HashCode);
      todo = GNUNET_MIN(fit,
                        left);
      env = GNUNET_MQ_msg_extra(sm,
                                sizeof(struct GNUNET_HashCode) * todo,
                                GNUNET_MESSAGE_TYPE_FS_START_SEARCH);
      mbc.skip_cnt = search_request_map_offset;
      mbc.xoff = (struct GNUNET_HashCode *)&sm[1];
      sm->type = htonl(GNUNET_BLOCK_TYPE_FS_UBLOCK);
      sm->anonymity_level = htonl(sc->anonymity);
      memset(&sm->target,
             0,
             sizeof(struct GNUNET_PeerIdentity));

      if (GNUNET_FS_uri_test_ksk(sc->uri))
        {
          mbc.keyword_offset = keyword_offset;
          /* calculate how many results we can send in this message */
          mbc.put_cnt = todo;
          /* now build message */
          sm->query = sc->requests[keyword_offset].uquery;
          GNUNET_CONTAINER_multihashmap_iterate(sc->master_result_map,
                                                &build_result_set,
                                                &mbc);
          search_request_map_offset += todo;
          GNUNET_assert(0 == mbc.put_cnt);
          GNUNET_assert(total_seen_results >= search_request_map_offset);
          if (total_seen_results != search_request_map_offset)
            {
              /* more requesting to be done... */
              sm->options = htonl(options | SEARCH_MESSAGE_OPTION_CONTINUED);
            }
          else
            {
              sm->options = htonl(options);
              keyword_offset++;
              if (sc->uri->data.ksk.keywordCount != keyword_offset)
                {
                  /* more keywords => more requesting to be done... */
                  first_call = GNUNET_YES;
                  search_request_map_offset = 0;
                  mbc.put_cnt = 0;
                  mbc.keyword_offset = keyword_offset;
                  GNUNET_CONTAINER_multihashmap_iterate(sc->master_result_map,
                                                        &find_result_set,
                                                        &mbc);
                  total_seen_results = mbc.put_cnt;
                }
            }
        }
      else
        {
          GNUNET_assert(GNUNET_FS_uri_test_sks(sc->uri));

          GNUNET_CRYPTO_ecdsa_public_key_derive(&sc->uri->data.sks.ns,
                                                sc->uri->data.sks.identifier,
                                                "fs-ublock",
                                                &dpub);
          GNUNET_CRYPTO_hash(&dpub,
                             sizeof(dpub),
                             &sm->query);
          mbc.put_cnt = todo;
          mbc.keyword_offset = 0;
          GNUNET_CONTAINER_multihashmap_iterate(sc->master_result_map,
                                                &build_result_set,
                                                &mbc);
          GNUNET_assert(total_seen_results >= search_request_map_offset);
          if (total_seen_results != search_request_map_offset)
            {
              /* more requesting to be done... */
              sm->options = htonl(options | SEARCH_MESSAGE_OPTION_CONTINUED);
            }
          else
            {
              sm->options = htonl(options);
            }
        }
      GNUNET_MQ_send(sc->mq,
                     env);
    }
}


static void
search_mq_error_handler(void *cls,
                        enum GNUNET_MQ_Error error)
{
  struct GNUNET_FS_SearchContext *sc = cls;

  if (NULL != sc->mq)
    {
      GNUNET_MQ_destroy(sc->mq);
      sc->mq = NULL;
    }
  try_reconnect(sc);
}


static void
do_reconnect(void *cls)
{
  struct GNUNET_FS_SearchContext *sc = cls;
  struct GNUNET_MQ_MessageHandler handlers[] = {
    GNUNET_MQ_hd_var_size(result,
                          GNUNET_MESSAGE_TYPE_FS_PUT,
                          struct ClientPutMessage,
                          sc),
    GNUNET_MQ_handler_end()
  };

  sc->task = NULL;
  sc->mq = GNUNET_CLIENT_connect(sc->h->cfg,
                                 "fs",
                                 handlers,
                                 &search_mq_error_handler,
                                 sc);
  if (NULL == sc->mq)
    {
      try_reconnect(sc);
      return;
    }
  schedule_transmit_search_request(sc);
}


static void
try_reconnect(struct GNUNET_FS_SearchContext *sc)
{
  if (NULL != sc->mq)
    {
      GNUNET_MQ_destroy(sc->mq);
      sc->mq = NULL;
    }
  sc->reconnect_backoff = GNUNET_TIME_STD_BACKOFF(sc->reconnect_backoff);
  sc->task =
    GNUNET_SCHEDULER_add_delayed(sc->reconnect_backoff,
                                 &do_reconnect,
                                 sc);
}


static struct GNUNET_FS_SearchContext *
search_start(struct GNUNET_FS_Handle *h,
             const struct GNUNET_FS_Uri *uri,
             uint32_t anonymity,
             enum GNUNET_FS_SearchOptions options,
             void *cctx,
             struct GNUNET_FS_SearchResult *psearch)
{
  struct GNUNET_FS_SearchContext *sc;
  struct GNUNET_FS_ProgressInfo pi;

  sc = GNUNET_new(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 (NULL != psearch)
    {
      sc->psearch_result = psearch;
      psearch->update_search = sc;
    }
  sc->master_result_map = GNUNET_CONTAINER_multihashmap_create(16, GNUNET_NO);
  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->h, sc);
  return sc;
}


static int
update_sre_result_maps(void *cls,
                       const struct GNUNET_HashCode *key,
                       void *value)
{
  struct GNUNET_FS_SearchContext *sc = cls;
  struct GNUNET_FS_SearchResult *sr = value;
  unsigned int i;

  for (i = 0; i < sc->uri->data.ksk.keywordCount; i++)
    if (0 != (sr->keyword_bitmap[i / 8] & (1 << (i % 8))))
      GNUNET_break(GNUNET_OK ==
                   GNUNET_CONTAINER_multihashmap_put(sc->requests[i].results,
                                                     &sr->key,
                                                     sr,
                                                     GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));

  return GNUNET_YES;
}


int
GNUNET_FS_search_start_searching_(struct GNUNET_FS_SearchContext *sc)
{
  unsigned int i;
  const char *keyword;
  const struct GNUNET_CRYPTO_EcdsaPrivateKey *anon;
  struct GNUNET_CRYPTO_EcdsaPublicKey anon_pub;
  struct SearchRequestEntry *sre;

  GNUNET_assert(NULL == sc->mq);
  if (GNUNET_FS_uri_test_ksk(sc->uri))
    {
      GNUNET_assert(0 != sc->uri->data.ksk.keywordCount);
      anon = GNUNET_CRYPTO_ecdsa_key_get_anonymous();
      GNUNET_CRYPTO_ecdsa_key_get_public(anon, &anon_pub);
      sc->requests
        = GNUNET_new_array(sc->uri->data.ksk.keywordCount,
                           struct SearchRequestEntry);

      for (i = 0; i < sc->uri->data.ksk.keywordCount; i++)
        {
          keyword = &sc->uri->data.ksk.keywords[i][1];
          sre = &sc->requests[i];
          sre->keyword = GNUNET_strdup(keyword);
          GNUNET_CRYPTO_ecdsa_public_key_derive(&anon_pub,
                                                keyword,
                                                "fs-ublock",
                                                &sre->dpub);
          GNUNET_CRYPTO_hash(&sre->dpub,
                             sizeof(struct GNUNET_CRYPTO_EcdsaPublicKey),
                             &sre->uquery);
          sre->mandatory = (sc->uri->data.ksk.keywords[i][0] == '+');
          if (sre->mandatory)
            sc->mandatory_count++;
          sre->results = GNUNET_CONTAINER_multihashmap_create(4, GNUNET_NO);
        }
      GNUNET_CONTAINER_multihashmap_iterate(sc->master_result_map,
                                            &update_sre_result_maps,
                                            sc);
    }
  GNUNET_assert(NULL == sc->task);
  do_reconnect(sc);
  if (NULL == sc->mq)
    {
      GNUNET_SCHEDULER_cancel(sc->task);
      sc->task = NULL;
      return GNUNET_SYSERR;
    }
  return GNUNET_OK;
}


static int
search_result_freeze_probes(void *cls,
                            const struct GNUNET_HashCode *key,
                            void *value)
{
  struct GNUNET_FS_SearchResult *sr = value;

  if (NULL != sr->probe_ctx)
    {
      GNUNET_FS_download_stop(sr->probe_ctx, GNUNET_YES);
      sr->probe_ctx = NULL;
      GNUNET_FS_stop_probe_ping_task_(sr);
    }
  if (NULL != sr->probe_cancel_task)
    {
      GNUNET_SCHEDULER_cancel(sr->probe_cancel_task);
      sr->probe_cancel_task = NULL;
    }
  if (NULL != sr->update_search)
    GNUNET_FS_search_pause(sr->update_search);
  return GNUNET_OK;
}


static int
search_result_resume_probes(void *cls,
                            const struct GNUNET_HashCode * key,
                            void *value)
{
  struct GNUNET_FS_SearchResult *sr = value;

  GNUNET_FS_search_start_probe_(sr);
  if (NULL != sr->update_search)
    GNUNET_FS_search_continue(sr->update_search);
  return GNUNET_OK;
}


static int
search_result_suspend(void *cls,
                      const struct GNUNET_HashCode *key,
                      void *value)
{
  struct GNUNET_FS_SearchContext *sc = cls;
  struct GNUNET_FS_SearchResult *sr = value;
  struct GNUNET_FS_ProgressInfo pi;

  if (NULL != sr->download)
    {
      GNUNET_FS_download_signal_suspend_(sr->download);
      sr->download = NULL;
    }
  if (NULL != sr->update_search)
    {
      GNUNET_FS_search_signal_suspend_(sr->update_search);
      sr->update_search = NULL;
    }
  GNUNET_FS_search_stop_probe_(sr);
  if (0 == sr->mandatory_missing)
    {
      /* client is aware of search result, notify about suspension event */
      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->h, 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);
  GNUNET_free_non_null(sr->keyword_bitmap);
  GNUNET_free(sr);
  return GNUNET_OK;
}


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->h, sc);
  GNUNET_break(NULL == sc->client_info);
  if (sc->task != NULL)
    {
      GNUNET_SCHEDULER_cancel(sc->task);
      sc->task = NULL;
    }
  if (NULL != sc->mq)
    {
      GNUNET_MQ_destroy(sc->mq);
      sc->mq = NULL;
    }
  GNUNET_CONTAINER_multihashmap_destroy(sc->master_result_map);
  if (NULL != sc->requests)
    {
      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(sc->requests[i].keyword);
        }
    }
  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);
}


struct GNUNET_FS_SearchContext *
GNUNET_FS_search_start(struct GNUNET_FS_Handle *h,
                       const struct GNUNET_FS_Uri *uri, uint32_t anonymity,
                       enum GNUNET_FS_SearchOptions options, void *cctx)
{
  struct GNUNET_FS_SearchContext *ret;

  ret = search_start(h, uri, anonymity, options, cctx, NULL);
  if (NULL == ret)
    return NULL;
  ret->top = GNUNET_FS_make_top(h, &GNUNET_FS_search_signal_suspend_, ret);
  return ret;
}


void
GNUNET_FS_search_pause(struct GNUNET_FS_SearchContext *sc)
{
  struct GNUNET_FS_ProgressInfo pi;

  if (NULL != sc->task)
    {
      GNUNET_SCHEDULER_cancel(sc->task);
      sc->task = NULL;
    }
  if (NULL != sc->mq)
    {
      GNUNET_MQ_destroy(sc->mq);
      sc->mq = NULL;
    }
  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;
  sc->client_info = GNUNET_FS_search_make_status_(&pi,
                                                  sc->h,
                                                  sc);
}


void
GNUNET_FS_search_continue(struct GNUNET_FS_SearchContext *sc)
{
  struct GNUNET_FS_ProgressInfo pi;

  GNUNET_assert(NULL == sc->mq);
  GNUNET_assert(NULL == sc->task);
  do_reconnect(sc);
  GNUNET_FS_search_sync_(sc);
  pi.status = GNUNET_FS_STATUS_SEARCH_CONTINUED;
  sc->client_info = GNUNET_FS_search_make_status_(&pi, sc->h, sc);
  GNUNET_CONTAINER_multihashmap_iterate(sc->master_result_map,
                                        &search_result_resume_probes, sc);
}


static int
search_result_stop(void *cls,
                   const struct GNUNET_HashCode *key,
                   void *value)
{
  struct GNUNET_FS_SearchContext *sc = cls;
  struct GNUNET_FS_SearchResult *sr = value;
  struct GNUNET_FS_ProgressInfo pi;

  GNUNET_FS_search_stop_probe_(sr);
  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 (0 != sr->mandatory_missing)
    {
      /* client is unaware of search result as
         it does not match required keywords */
      GNUNET_break(NULL == sr->client_info);
      return GNUNET_OK;
    }
  pi.status = GNUNET_FS_STATUS_SEARCH_RESULT_STOPPED;
  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 = GNUNET_FS_search_make_status_(&pi, sr->h, sc);
  return GNUNET_OK;
}


static int
search_result_free(void *cls,
                   const struct GNUNET_HashCode *key,
                   void *value)
{
  struct GNUNET_FS_SearchResult *sr = value;

  if (NULL != sr->update_search)
    {
      GNUNET_FS_search_stop(sr->update_search);
      GNUNET_assert(NULL == sr->update_search);
    }
  GNUNET_break(NULL == sr->probe_ctx);
  GNUNET_break(NULL == sr->probe_cancel_task);
  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);
  GNUNET_free_non_null(sr->keyword_bitmap);
  GNUNET_free(sr);
  return GNUNET_OK;
}


void
GNUNET_FS_search_stop(struct GNUNET_FS_SearchContext *sc)
{
  struct GNUNET_FS_ProgressInfo pi;
  unsigned int i;

  if (NULL != sc->top)
    GNUNET_FS_end_top(sc->h, sc->top);
  GNUNET_CONTAINER_multihashmap_iterate(sc->master_result_map,
                                        &search_result_stop,
                                        sc);
  if (NULL != sc->psearch_result)
    sc->psearch_result->update_search = NULL;
  if (NULL != sc->serialization)
    {
      GNUNET_FS_remove_sync_file_(sc->h,
                                  (NULL != sc->psearch_result)
                                  ? GNUNET_FS_SYNC_PATH_CHILD_SEARCH
                                  : GNUNET_FS_SYNC_PATH_MASTER_SEARCH,
                                  sc->serialization);
      GNUNET_FS_remove_sync_dir_(sc->h,
                                 (NULL != sc->psearch_result)
                                 ? 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;
  sc->client_info = GNUNET_FS_search_make_status_(&pi,
                                                  sc->h,
                                                  sc);
  GNUNET_break(NULL == sc->client_info);
  if (NULL != sc->task)
    {
      GNUNET_SCHEDULER_cancel(sc->task);
      sc->task = NULL;
    }
  if (NULL != sc->mq)
    {
      GNUNET_MQ_destroy(sc->mq);
      sc->mq = NULL;
    }
  GNUNET_CONTAINER_multihashmap_iterate(sc->master_result_map,
                                        &search_result_free, sc);
  GNUNET_CONTAINER_multihashmap_destroy(sc->master_result_map);
  if (NULL != sc->requests)
    {
      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);
}

/* end of fs_search.c */