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diff --git a/src/cadet/gnunet-service-cadet_channel.h b/src/cadet/gnunet-service-cadet_channel.h
new file mode 100644
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+++ b/src/cadet/gnunet-service-cadet_channel.h
@@ -0,0 +1,349 @@
+/*
+     This file is part of GNUnet.
+     (C) 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 cadet/gnunet-service-cadet_channel.h
+ * @brief cadet service; dealing with end-to-end channels
+ * @author Bartlomiej Polot
+ *
+ * All functions in this file should use the prefix GMCH (Gnunet Cadet CHannel)
+ */
+
+#ifndef GNUNET_SERVICE_CADET_CHANNEL_H
+#define GNUNET_SERVICE_CADET_CHANNEL_H
+
+#ifdef __cplusplus
+extern "C"
+{
+#if 0                           /* keep Emacsens' auto-indent happy */
+}
+#endif
+#endif
+
+#include "platform.h"
+#include "gnunet_util_lib.h"
+
+#include "cadet_protocol.h"
+#include "cadet.h"
+
+/**
+ * Struct containing all information regarding a channel to a remote client.
+ */
+struct CadetChannel;
+
+
+#include "gnunet-service-cadet_tunnel.h"
+#include "gnunet-service-cadet_local.h"
+
+
+/**
+ * Destroy a channel and free all resources.
+ *
+ * @param ch Channel to destroy.
+ */
+void
+GMCH_destroy (struct CadetChannel *ch);
+
+
+/**
+ * Get the channel's public ID.
+ *
+ * @param ch Channel.
+ *
+ * @return ID used to identify the channel with the remote peer.
+ */
+CADET_ChannelNumber
+GMCH_get_id (const struct CadetChannel *ch);
+
+/**
+ * Get the channel tunnel.
+ *
+ * @param ch Channel to get the tunnel from.
+ *
+ * @return tunnel of the channel.
+ */
+struct CadetTunnel3 *
+GMCH_get_tunnel (const struct CadetChannel *ch);
+
+/**
+ * Get free buffer space towards the client on a specific channel.
+ *
+ * @param ch Channel.
+ * @param fwd Is query about FWD traffic?
+ *
+ * @return Free buffer space [0 - 64]
+ */
+unsigned int
+GMCH_get_buffer (struct CadetChannel *ch, int fwd);
+
+
+/**
+ * Get flow control status of end point: is client allow to send?
+ *
+ * @param ch Channel.
+ * @param fwd Is query about FWD traffic? (Request root status).
+ *
+ * @return #GNUNET_YES if client is allowed to send us data.
+ */
+int
+GMCH_get_allowed (struct CadetChannel *ch, int fwd);
+
+
+/**
+ * Is the root client for this channel on this peer?
+ *
+ * @param ch Channel.
+ * @param fwd Is this for fwd traffic?
+ *
+ * @return #GNUNET_YES in case it is.
+ */
+int
+GMCH_is_origin (struct CadetChannel *ch, int fwd);
+
+/**
+ * Is the destination client for this channel on this peer?
+ *
+ * @param ch Channel.
+ * @param fwd Is this for fwd traffic?
+ *
+ * @return #GNUNET_YES in case it is.
+ */
+int
+GMCH_is_terminal (struct CadetChannel *ch, int fwd);
+
+/**
+ * Send an end-to-end ACK message for the most recent in-sequence payload.
+ *
+ * If channel is not reliable, do nothing.
+ *
+ * @param ch Channel this is about.
+ * @param fwd Is for FWD traffic? (ACK dest->owner)
+ */
+void
+GMCH_send_data_ack (struct CadetChannel *ch, int fwd);
+
+/**
+ * Notify the destination client that a new incoming channel was created.
+ *
+ * @param ch Channel that was created.
+ */
+void
+GMCH_send_create (struct CadetChannel *ch);
+
+/**
+ * Allow a client to send us more data, in case it was choked.
+ *
+ * @param ch Channel.
+ * @param fwd Is this about FWD traffic? (Root client).
+ */
+void
+GMCH_allow_client (struct CadetChannel *ch, int fwd);
+
+/**
+ * Log channel info.
+ *
+ * @param ch Channel.
+ */
+void
+GMCH_debug (struct CadetChannel *ch);
+
+/**
+ * Handle an ACK given by a client.
+ *
+ * Mark client as ready and send him any buffered data we could have for him.
+ *
+ * @param ch Channel.
+ * @param fwd Is this a "FWD ACK"? (FWD ACKs are sent by root and go BCK)
+ */
+void
+GMCH_handle_local_ack (struct CadetChannel *ch, int fwd);
+
+/**
+ * Handle data given by a client.
+ *
+ * Check whether the client is allowed to send in this tunnel, save if channel
+ * is reliable and send an ACK to the client if there is still buffer space
+ * in the tunnel.
+ *
+ * @param ch Channel.
+ * @param c Client which sent the data.
+ * @param message Message.
+ * @param fwd Is this a FWD data?
+ *
+ * @return GNUNET_OK if everything goes well, GNUNET_SYSERR in case of en error.
+ */
+int
+GMCH_handle_local_data (struct CadetChannel *ch,
+                        struct CadetClient *c,
+                        struct GNUNET_MessageHeader *message,
+                        int fwd);
+
+/**
+ * Handle a channel destroy requested by a client.
+ *
+ * Destroy the channel and the tunnel in case this was the last channel.
+ *
+ * @param ch Channel.
+ * @param c Client that requested the destruction (to avoid notifying him).
+ * @param is_root Is the request coming from root?
+ */
+void
+GMCH_handle_local_destroy (struct CadetChannel *ch,
+                           struct CadetClient *c,
+                           int is_root);
+
+/**
+ * Handle a channel create requested by a client.
+ *
+ * Create the channel and the tunnel in case this was the first0 channel.
+ *
+ * @param c Client that requested the creation (will be the root).
+ * @param msg Create Channel message.
+ *
+ * @return GNUNET_OK if everything went fine, GNUNET_SYSERR otherwise.
+ */
+int
+GMCH_handle_local_create (struct CadetClient *c,
+                          struct GNUNET_CADET_ChannelMessage *msg);
+
+/**
+ * Handler for cadet network payload traffic.
+ *
+ * @param ch Channel for the message.
+ * @param msg Unencryted data message.
+ * @param fwd Is this message fwd? This only is meaningful in loopback channels.
+ *            #GNUNET_YES if message is FWD on the respective channel (loopback)
+ *            #GNUNET_NO if message is BCK on the respective channel (loopback)
+ *            #GNUNET_SYSERR if message on a one-ended channel (remote)
+ */
+void
+GMCH_handle_data (struct CadetChannel *ch,
+                  const struct GNUNET_CADET_Data *msg,
+                  int fwd);
+
+/**
+ * Handler for cadet network traffic end-to-end ACKs.
+ *
+ * @param ch Channel on which we got this message.
+ * @param msg Data message.
+ * @param fwd Is this message fwd? This only is meaningful in loopback channels.
+ *            #GNUNET_YES if message is FWD on the respective channel (loopback)
+ *            #GNUNET_NO if message is BCK on the respective channel (loopback)
+ *            #GNUNET_SYSERR if message on a one-ended channel (remote)
+ */
+void
+GMCH_handle_data_ack (struct CadetChannel *ch,
+                      const struct GNUNET_CADET_DataACK *msg,
+                      int fwd);
+
+/**
+ * Handler for channel create messages.
+ *
+ * Does not have fwd parameter because it's always 'FWD': channel is incoming.
+ *
+ * @param t Tunnel this channel will be in.
+ * @param msg Channel crate message.
+ */
+struct CadetChannel *
+GMCH_handle_create (struct CadetTunnel3 *t,
+                    const struct GNUNET_CADET_ChannelCreate *msg);
+
+/**
+ * Handler for channel NACK messages.
+ *
+ * NACK messages always go dest -> root, no need for 'fwd' or 'msg' parameter.
+ *
+ * @param ch Channel.
+ */
+void
+GMCH_handle_nack (struct CadetChannel *ch);
+
+/**
+ * Handler for channel ack messages.
+ *
+ * @param ch Channel this channel is to be created in.
+ * @param msg Message.
+ * @param fwd Is this message fwd? This only is meaningful in loopback channels.
+ *            #GNUNET_YES if message is FWD on the respective channel (loopback)
+ *            #GNUNET_NO if message is BCK on the respective channel (loopback)
+ *            #GNUNET_SYSERR if message on a one-ended channel (remote)
+ */
+void
+GMCH_handle_ack (struct CadetChannel *ch,
+                 const struct GNUNET_CADET_ChannelManage *msg,
+                 int fwd);
+
+/**
+ * Handler for channel destroy messages.
+ *
+ * @param ch Channel this channel is to be destroyed of.
+ * @param msg Message.
+ * @param fwd Is this message fwd? This only is meaningful in loopback channels.
+ *            #GNUNET_YES if message is FWD on the respective channel (loopback)
+ *            #GNUNET_NO if message is BCK on the respective channel (loopback)
+ *            #GNUNET_SYSERR if message on a one-ended channel (remote)
+ */
+void
+GMCH_handle_destroy (struct CadetChannel *ch,
+                     const struct GNUNET_CADET_ChannelManage *msg,
+                     int fwd);
+
+/**
+ * Sends an already built message on a channel.
+ *
+ * If the channel is on a loopback tunnel, notifies the appropriate destination
+ * client locally.
+ *
+ * On a normal channel passes the message to the tunnel for encryption and
+ * sending on a connection.
+ *
+ * This function DOES NOT save the message for retransmission.
+ *
+ * @param message Message to send. Function makes a copy of it.
+ * @param ch Channel on which this message is transmitted.
+ * @param fwd Is this a fwd message?
+ * @param existing_copy This is a retransmission, don't save a copy.
+ */
+void
+GMCH_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
+                            struct CadetChannel *ch, int fwd,
+                            void *existing_copy);
+
+/**
+ * Get the static string for identification of the channel.
+ *
+ * @param ch Channel.i
+ *
+ * @return Static string with the channel IDs.
+ */
+const char *
+GMCH_2s (const struct CadetChannel *ch);
+
+
+#if 0                           /* keep Emacsens' auto-indent happy */
+{
+#endif
+#ifdef __cplusplus
+}
+#endif
+
+/* ifndef GNUNET_SERVICE_CADET_CHANNEL_H */
+#endif
+/* end of gnunet-service-cadet_channel.h */