1 files changed, 766 insertions, 0 deletions

diff --git a/src/fs/gnunet-service-fs_cadet_client.c b/src/fs/gnunet-service-fs_cadet_client.c
new file mode 100644
index 000000000..dde7aba48
--- /dev/null
+++ b/src/fs/gnunet-service-fs_cadet_client.c
@@ -0,0 +1,766 @@
+/*
+     This file is part of GNUnet.
+     (C) 2012, 2013 Christian Grothoff (and other contributing authors)
+
+     GNUnet is free software; you can redistribute it and/or modify
+     it under the terms of the GNU General Public License as published
+     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
+     WITHOUT ANY WARRANTY; without even the implied warranty of
+     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with GNUnet; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+*/
+
+/**
+ * @file fs/gnunet-service-fs_cadet_client.c
+ * @brief non-anonymous file-transfer
+ * @author Christian Grothoff
+ *
+ * TODO:
+ * - PORT is set to old application type, unsure if we should keep
+ *   it that way (fine for now)
+ */
+#include "platform.h"
+#include "gnunet_constants.h"
+#include "gnunet_util_lib.h"
+#include "gnunet_cadet_service.h"
+#include "gnunet_protocols.h"
+#include "gnunet_applications.h"
+#include "gnunet-service-fs.h"
+#include "gnunet-service-fs_indexing.h"
+#include "gnunet-service-fs_cadet.h"
+
+
+/**
+ * After how long do we reset connections without replies?
+ */
+#define CLIENT_RETRY_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30)
+
+
+/**
+ * Handle for a cadet to another peer.
+ */
+struct CadetHandle;
+
+
+/**
+ * Handle for a request that is going out via cadet API.
+ */
+struct GSF_CadetRequest
+{
+
+  /**
+   * DLL.
+   */
+  struct GSF_CadetRequest *next;
+
+  /**
+   * DLL.
+   */
+  struct GSF_CadetRequest *prev;
+
+  /**
+   * Which cadet is this request associated with?
+   */
+  struct CadetHandle *mh;
+
+  /**
+   * Function to call with the result.
+   */
+  GSF_CadetReplyProcessor proc;
+
+  /**
+   * Closure for 'proc'
+   */
+  void *proc_cls;
+
+  /**
+   * Query to transmit to the other peer.
+   */
+  struct GNUNET_HashCode query;
+
+  /**
+   * Desired type for the reply.
+   */
+  enum GNUNET_BLOCK_Type type;
+
+  /**
+   * Did we transmit this request already? #GNUNET_YES if we are
+   * in the 'waiting_map', #GNUNET_NO if we are in the 'pending' DLL.
+   */
+  int was_transmitted;
+};
+
+
+/**
+ * Handle for a cadet to another peer.
+ */
+struct CadetHandle
+{
+  /**
+   * Head of DLL of pending requests on this cadet.
+   */
+  struct GSF_CadetRequest *pending_head;
+
+  /**
+   * Tail of DLL of pending requests on this cadet.
+   */
+  struct GSF_CadetRequest *pending_tail;
+
+  /**
+   * Map from query to `struct GSF_CadetRequest`s waiting for
+   * a reply.
+   */
+  struct GNUNET_CONTAINER_MultiHashMap *waiting_map;
+
+  /**
+   * Channel to the other peer.
+   */
+  struct GNUNET_CADET_Channel *channel;
+
+  /**
+   * Handle for active write operation, or NULL.
+   */
+  struct GNUNET_CADET_TransmitHandle *wh;
+
+  /**
+   * Which peer does this cadet go to?
+   */
+  struct GNUNET_PeerIdentity target;
+
+  /**
+   * Task to kill inactive cadets (we keep them around for
+   * a few seconds to give the application a chance to give
+   * us another query).
+   */
+  GNUNET_SCHEDULER_TaskIdentifier timeout_task;
+
+  /**
+   * Task to reset cadets that had errors (asynchronously,
+   * as we may not be able to do it immediately during a
+   * callback from the cadet API).
+   */
+  GNUNET_SCHEDULER_TaskIdentifier reset_task;
+
+};
+
+
+/**
+ * Cadet channel for creating outbound channels.
+ */
+static struct GNUNET_CADET_Handle *cadet_handle;
+
+/**
+ * Map from peer identities to 'struct CadetHandles' with cadet
+ * channels to those peers.
+ */
+static struct GNUNET_CONTAINER_MultiPeerMap *cadet_map;
+
+
+/* ********************* client-side code ************************* */
+
+
+/**
+ * Transmit pending requests via the cadet.
+ *
+ * @param mh cadet to process
+ */
+static void
+transmit_pending (struct CadetHandle *mh);
+
+
+/**
+ * Iterator called on each entry in a waiting map to
+ * move it back to the pending list.
+ *
+ * @param cls the `struct CadetHandle`
+ * @param key the key of the entry in the map (the query)
+ * @param value the `struct GSF_CadetRequest` to move to pending
+ * @return #GNUNET_YES (continue to iterate)
+ */
+static int
+move_to_pending (void *cls,
+                 const struct GNUNET_HashCode *key,
+                 void *value)
+{
+  struct CadetHandle *mh = cls;
+  struct GSF_CadetRequest *sr = value;
+
+  GNUNET_assert (GNUNET_YES ==
+                 GNUNET_CONTAINER_multihashmap_remove (mh->waiting_map,
+                                                       key,
+                                                       value));
+  GNUNET_CONTAINER_DLL_insert (mh->pending_head,
+                               mh->pending_tail,
+                               sr);
+  sr->was_transmitted = GNUNET_NO;
+  return GNUNET_YES;
+}
+
+
+/**
+ * We had a serious error, tear down and re-create cadet from scratch.
+ *
+ * @param mh cadet to reset
+ */
+static void
+reset_cadet (struct CadetHandle *mh)
+{
+  struct GNUNET_CADET_Channel *channel = mh->channel;
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Resetting cadet channel to %s\n",
+              GNUNET_i2s (&mh->target));
+  mh->channel = NULL;
+  if (NULL != channel)
+    GNUNET_CADET_channel_destroy (channel);
+  GNUNET_CONTAINER_multihashmap_iterate (mh->waiting_map,
+                                         &move_to_pending,
+                                         mh);
+  mh->channel = GNUNET_CADET_channel_create (cadet_handle,
+                                          mh,
+                                          &mh->target,
+                                          GNUNET_APPLICATION_TYPE_FS_BLOCK_TRANSFER,
+                                          GNUNET_CADET_OPTION_RELIABLE);
+  transmit_pending (mh);
+}
+
+
+/**
+ * Task called when it is time to destroy an inactive cadet channel.
+ *
+ * @param cls the `struct CadetHandle` to tear down
+ * @param tc scheduler context, unused
+ */
+static void
+cadet_timeout (void *cls,
+              const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct CadetHandle *mh = cls;
+  struct GNUNET_CADET_Channel *tun;
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Timeout on cadet channel to %s\n",
+              GNUNET_i2s (&mh->target));
+  mh->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+  tun = mh->channel;
+  mh->channel = NULL;
+  GNUNET_CADET_channel_destroy (tun);
+}
+
+
+/**
+ * Task called when it is time to reset an cadet.
+ *
+ * @param cls the `struct CadetHandle` to tear down
+ * @param tc scheduler context, unused
+ */
+static void
+reset_cadet_task (void *cls,
+                 const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct CadetHandle *mh = cls;
+
+  mh->reset_task = GNUNET_SCHEDULER_NO_TASK;
+  reset_cadet (mh);
+}
+
+
+/**
+ * We had a serious error, tear down and re-create cadet from scratch,
+ * but do so asynchronously.
+ *
+ * @param mh cadet to reset
+ */
+static void
+reset_cadet_async (struct CadetHandle *mh)
+{
+  if (GNUNET_SCHEDULER_NO_TASK != mh->reset_task)
+    GNUNET_SCHEDULER_cancel (mh->reset_task);
+  mh->reset_task = GNUNET_SCHEDULER_add_now (&reset_cadet_task,
+                                             mh);
+}
+
+
+/**
+ * Functions of this signature are called whenever we are ready to transmit
+ * query via a cadet.
+ *
+ * @param cls the struct CadetHandle for which we did the write call
+ * @param size the number of bytes that can be written to @a buf
+ * @param buf where to write the message
+ * @return number of bytes written to @a buf
+ */
+static size_t
+transmit_sqm (void *cls,
+              size_t size,
+              void *buf)
+{
+  struct CadetHandle *mh = cls;
+  struct CadetQueryMessage sqm;
+  struct GSF_CadetRequest *sr;
+
+  mh->wh = NULL;
+  if (NULL == buf)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+                "Cadet channel to %s failed during transmission attempt, rebuilding\n",
+                GNUNET_i2s (&mh->target));
+    reset_cadet_async (mh);
+    return 0;
+  }
+  sr = mh->pending_head;
+  if (NULL == sr)
+    return 0;
+  GNUNET_assert (size >= sizeof (struct CadetQueryMessage));
+  GNUNET_CONTAINER_DLL_remove (mh->pending_head,
+                               mh->pending_tail,
+                               sr);
+  GNUNET_assert (GNUNET_OK ==
+                 GNUNET_CONTAINER_multihashmap_put (mh->waiting_map,
+                                                    &sr->query,
+                                                    sr,
+                                                    GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE));
+  sr->was_transmitted = GNUNET_YES;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Sending query for %s via cadet to %s\n",
+              GNUNET_h2s (&sr->query),
+              GNUNET_i2s (&mh->target));
+  sqm.header.size = htons (sizeof (sqm));
+  sqm.header.type = htons (GNUNET_MESSAGE_TYPE_FS_CADET_QUERY);
+  sqm.type = htonl (sr->type);
+  sqm.query = sr->query;
+  memcpy (buf, &sqm, sizeof (sqm));
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Successfully transmitted %u bytes via cadet to %s\n",
+              (unsigned int) size,
+              GNUNET_i2s (&mh->target));
+  transmit_pending (mh);
+  return sizeof (sqm);
+}
+
+
+/**
+ * Transmit pending requests via the cadet.
+ *
+ * @param mh cadet to process
+ */
+static void
+transmit_pending (struct CadetHandle *mh)
+{
+  if (NULL == mh->channel)
+    return;
+  if (NULL != mh->wh)
+    return;
+  mh->wh = GNUNET_CADET_notify_transmit_ready (mh->channel, GNUNET_YES /* allow cork */,
+                                              GNUNET_TIME_UNIT_FOREVER_REL,
+                                              sizeof (struct CadetQueryMessage),
+                                              &transmit_sqm, mh);
+}
+
+
+/**
+ * Closure for handle_reply().
+ */
+struct HandleReplyClosure
+{
+
+  /**
+   * Reply payload.
+   */
+  const void *data;
+
+  /**
+   * Expiration time for the block.
+   */
+  struct GNUNET_TIME_Absolute expiration;
+
+  /**
+   * Number of bytes in 'data'.
+   */
+  size_t data_size;
+
+  /**
+   * Type of the block.
+   */
+  enum GNUNET_BLOCK_Type type;
+
+  /**
+   * Did we have a matching query?
+   */
+  int found;
+};
+
+
+/**
+ * Iterator called on each entry in a waiting map to
+ * process a result.
+ *
+ * @param cls the `struct HandleReplyClosure`
+ * @param key the key of the entry in the map (the query)
+ * @param value the `struct GSF_CadetRequest` to handle result for
+ * @return #GNUNET_YES (continue to iterate)
+ */
+static int
+handle_reply (void *cls,
+              const struct GNUNET_HashCode *key,
+              void *value)
+{
+  struct HandleReplyClosure *hrc = cls;
+  struct GSF_CadetRequest *sr = value;
+
+  sr->proc (sr->proc_cls,
+            hrc->type,
+            hrc->expiration,
+            hrc->data_size,
+            hrc->data);
+  sr->proc = NULL;
+  GSF_cadet_query_cancel (sr);
+  hrc->found = GNUNET_YES;
+  return GNUNET_YES;
+}
+
+
+/**
+ * Functions with this signature are called whenever a complete reply
+ * is received.
+ *
+ * @param cls closure with the `struct CadetHandle`
+ * @param channel channel handle
+ * @param channel_ctx channel context
+ * @param message the actual message
+ * @return #GNUNET_OK on success, #GNUNET_SYSERR to stop further processing
+ */
+static int
+reply_cb (void *cls,
+          struct GNUNET_CADET_Channel *channel,
+          void **channel_ctx,
+          const struct GNUNET_MessageHeader *message)
+{
+  struct CadetHandle *mh = *channel_ctx;
+  const struct CadetReplyMessage *srm;
+  struct HandleReplyClosure hrc;
+  uint16_t msize;
+  enum GNUNET_BLOCK_Type type;
+  struct GNUNET_HashCode query;
+
+  msize = ntohs (message->size);
+  if (sizeof (struct CadetReplyMessage) > msize)
+  {
+    GNUNET_break_op (0);
+    reset_cadet_async (mh);
+    return GNUNET_SYSERR;
+  }
+  srm = (const struct CadetReplyMessage *) message;
+  msize -= sizeof (struct CadetReplyMessage);
+  type = (enum GNUNET_BLOCK_Type) ntohl (srm->type);
+  if (GNUNET_YES !=
+      GNUNET_BLOCK_get_key (GSF_block_ctx,
+                            type,
+                            &srm[1], msize, &query))
+  {
+    GNUNET_break_op (0);
+    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+                "Received bogus reply of type %u with %u bytes via cadet from peer %s\n",
+                type,
+                msize,
+                GNUNET_i2s (&mh->target));
+    reset_cadet_async (mh);
+    return GNUNET_SYSERR;
+  }
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Received reply `%s' via cadet from peer %s\n",
+              GNUNET_h2s (&query),
+              GNUNET_i2s (&mh->target));
+  GNUNET_CADET_receive_done (channel);
+  GNUNET_STATISTICS_update (GSF_stats,
+                            gettext_noop ("# replies received via cadet"), 1,
+                            GNUNET_NO);
+  hrc.data = &srm[1];
+  hrc.data_size = msize;
+  hrc.expiration = GNUNET_TIME_absolute_ntoh (srm->expiration);
+  hrc.type = type;
+  hrc.found = GNUNET_NO;
+  GNUNET_CONTAINER_multihashmap_get_multiple (mh->waiting_map,
+                                              &query,
+                                              &handle_reply,
+                                              &hrc);
+  if (GNUNET_NO == hrc.found)
+  {
+    GNUNET_STATISTICS_update (GSF_stats,
+                              gettext_noop ("# replies received via cadet dropped"), 1,
+                              GNUNET_NO);
+    return GNUNET_OK;
+  }
+  return GNUNET_OK;
+}
+
+
+/**
+ * Get (or create) a cadet to talk to the given peer.
+ *
+ * @param target peer we want to communicate with
+ */
+static struct CadetHandle *
+get_cadet (const struct GNUNET_PeerIdentity *target)
+{
+  struct CadetHandle *mh;
+
+  mh = GNUNET_CONTAINER_multipeermap_get (cadet_map,
+                                          target);
+  if (NULL != mh)
+  {
+    if (GNUNET_SCHEDULER_NO_TASK != mh->timeout_task)
+    {
+      GNUNET_SCHEDULER_cancel (mh->timeout_task);
+      mh->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+    }
+    return mh;
+  }
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Creating cadet channel to %s\n",
+              GNUNET_i2s (target));
+  mh = GNUNET_new (struct CadetHandle);
+  mh->reset_task = GNUNET_SCHEDULER_add_delayed (CLIENT_RETRY_TIMEOUT,
+                                                 &reset_cadet_task,
+                                                 mh);
+  mh->waiting_map = GNUNET_CONTAINER_multihashmap_create (16, GNUNET_YES);
+  mh->target = *target;
+  GNUNET_assert (GNUNET_OK ==
+                 GNUNET_CONTAINER_multipeermap_put (cadet_map,
+                                                    &mh->target,
+                                                    mh,
+                                                    GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
+  mh->channel = GNUNET_CADET_channel_create (cadet_handle,
+                                            mh,
+                                            &mh->target,
+                                            GNUNET_APPLICATION_TYPE_FS_BLOCK_TRANSFER,
+                                            GNUNET_CADET_OPTION_RELIABLE);
+  GNUNET_assert (mh ==
+                 GNUNET_CONTAINER_multipeermap_get (cadet_map,
+                                                    target));
+  return mh;
+}
+
+
+/**
+ * Look for a block by directly contacting a particular peer.
+ *
+ * @param target peer that should have the block
+ * @param query hash to query for the block
+ * @param type desired type for the block
+ * @param proc function to call with result
+ * @param proc_cls closure for @a proc
+ * @return handle to cancel the operation
+ */
+struct GSF_CadetRequest *
+GSF_cadet_query (const struct GNUNET_PeerIdentity *target,
+                const struct GNUNET_HashCode *query,
+                enum GNUNET_BLOCK_Type type,
+                GSF_CadetReplyProcessor proc, void *proc_cls)
+{
+  struct CadetHandle *mh;
+  struct GSF_CadetRequest *sr;
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Preparing to send query for %s via cadet to %s\n",
+              GNUNET_h2s (query),
+              GNUNET_i2s (target));
+  mh = get_cadet (target);
+  sr = GNUNET_new (struct GSF_CadetRequest);
+  sr->mh = mh;
+  sr->proc = proc;
+  sr->proc_cls = proc_cls;
+  sr->type = type;
+  sr->query = *query;
+  GNUNET_CONTAINER_DLL_insert (mh->pending_head,
+                               mh->pending_tail,
+                               sr);
+  transmit_pending (mh);
+  return sr;
+}
+
+
+/**
+ * Cancel an active request; must not be called after 'proc'
+ * was calld.
+ *
+ * @param sr request to cancel
+ */
+void
+GSF_cadet_query_cancel (struct GSF_CadetRequest *sr)
+{
+  struct CadetHandle *mh = sr->mh;
+  GSF_CadetReplyProcessor p;
+
+  p = sr->proc;
+  sr->proc = NULL;
+  if (NULL != p)
+  {
+    /* signal failure / cancellation to callback */
+    p (sr->proc_cls, GNUNET_BLOCK_TYPE_ANY,
+       GNUNET_TIME_UNIT_ZERO_ABS,
+       0, NULL);
+  }
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Cancelled query for %s via cadet to %s\n",
+              GNUNET_h2s (&sr->query),
+              GNUNET_i2s (&sr->mh->target));
+  if (GNUNET_YES == sr->was_transmitted)
+    GNUNET_assert (GNUNET_OK ==
+                   GNUNET_CONTAINER_multihashmap_remove (mh->waiting_map,
+                                                         &sr->query,
+                                                         sr));
+  else
+    GNUNET_CONTAINER_DLL_remove (mh->pending_head,
+                                 mh->pending_tail,
+                                 sr);
+  GNUNET_free (sr);
+  if ( (0 == GNUNET_CONTAINER_multihashmap_size (mh->waiting_map)) &&
+       (NULL == mh->pending_head) )
+    mh->timeout_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS,
+                                                     &cadet_timeout,
+                                                     mh);
+}
+
+
+/**
+ * Iterator called on each entry in a waiting map to
+ * call the 'proc' continuation and release associated
+ * resources.
+ *
+ * @param cls the `struct CadetHandle`
+ * @param key the key of the entry in the map (the query)
+ * @param value the `struct GSF_CadetRequest` to clean up
+ * @return #GNUNET_YES (continue to iterate)
+ */
+static int
+free_waiting_entry (void *cls,
+                    const struct GNUNET_HashCode *key,
+                    void *value)
+{
+  struct GSF_CadetRequest *sr = value;
+
+  GSF_cadet_query_cancel (sr);
+  return GNUNET_YES;
+}
+
+
+/**
+ * Function called by cadet when a client disconnects.
+ * Cleans up our `struct CadetClient` of that channel.
+ *
+ * @param cls NULL
+ * @param channel channel of the disconnecting client
+ * @param channel_ctx our `struct CadetClient`
+ */
+static void
+cleaner_cb (void *cls,
+            const struct GNUNET_CADET_Channel *channel,
+            void *channel_ctx)
+{
+  struct CadetHandle *mh = channel_ctx;
+  struct GSF_CadetRequest *sr;
+
+  if (NULL == mh->channel)
+    return; /* being destroyed elsewhere */
+  GNUNET_assert (channel == mh->channel);
+  mh->channel = NULL;
+  while (NULL != (sr = mh->pending_head))
+    GSF_cadet_query_cancel (sr);
+  /* first remove `mh` from the `cadet_map`, so that if the
+     callback from `free_waiting_entry()` happens to re-issue
+     the request, we don't immediately have it back in the
+     `waiting_map`. */
+  GNUNET_assert (GNUNET_OK ==
+                 GNUNET_CONTAINER_multipeermap_remove (cadet_map,
+                                                       &mh->target,
+                                                       mh));
+  GNUNET_CONTAINER_multihashmap_iterate (mh->waiting_map,
+                                         &free_waiting_entry,
+                                         mh);
+  if (NULL != mh->wh)
+    GNUNET_CADET_notify_transmit_ready_cancel (mh->wh);
+  if (GNUNET_SCHEDULER_NO_TASK != mh->timeout_task)
+    GNUNET_SCHEDULER_cancel (mh->timeout_task);
+  if (GNUNET_SCHEDULER_NO_TASK != mh->reset_task)
+    GNUNET_SCHEDULER_cancel (mh->reset_task);
+  GNUNET_assert (0 ==
+                 GNUNET_CONTAINER_multihashmap_size (mh->waiting_map));
+  GNUNET_CONTAINER_multihashmap_destroy (mh->waiting_map);
+  GNUNET_free (mh);
+}
+
+
+/**
+ * Initialize subsystem for non-anonymous file-sharing.
+ */
+void
+GSF_cadet_start_client ()
+{
+  static const struct GNUNET_CADET_MessageHandler handlers[] = {
+    { &reply_cb, GNUNET_MESSAGE_TYPE_FS_CADET_REPLY, 0 },
+    { NULL, 0, 0 }
+  };
+
+  cadet_map = GNUNET_CONTAINER_multipeermap_create (16, GNUNET_YES);
+  cadet_handle = GNUNET_CADET_connect (GSF_cfg,
+                                     NULL,
+                                     NULL,
+                                     &cleaner_cb,
+                                     handlers,
+                                     NULL);
+}
+
+
+/**
+ * Function called on each active cadets to shut them down.
+ *
+ * @param cls NULL
+ * @param key target peer, unused
+ * @param value the `struct CadetHandle` to destroy
+ * @return #GNUNET_YES (continue to iterate)
+ */
+static int
+release_cadets (void *cls,
+               const struct GNUNET_PeerIdentity *key,
+               void *value)
+{
+  struct CadetHandle *mh = value;
+
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Timeout on cadet channel to %s\n",
+              GNUNET_i2s (&mh->target));
+  if (NULL != mh->channel)
+    GNUNET_CADET_channel_destroy (mh->channel);
+  return GNUNET_YES;
+}
+
+
+/**
+ * Shutdown subsystem for non-anonymous file-sharing.
+ */
+void
+GSF_cadet_stop_client ()
+{
+  GNUNET_CONTAINER_multipeermap_iterate (cadet_map,
+                                         &release_cadets,
+                                         NULL);
+  GNUNET_CONTAINER_multipeermap_destroy (cadet_map);
+  cadet_map = NULL;
+  if (NULL != cadet_handle)
+  {
+    GNUNET_CADET_disconnect (cadet_handle);
+    cadet_handle = NULL;
+  }
+}
+
+
+/* end of gnunet-service-fs_cadet_client.c */