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diff --git a/src/service/cadet/gnunet-service-cadet_paths.h b/src/service/cadet/gnunet-service-cadet_paths.h
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+++ b/src/service/cadet/gnunet-service-cadet_paths.h
@@ -0,0 +1,183 @@
+/*
+     This file is part of GNUnet.
+     Copyright (C) 2001-2017 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
+ */
+
+/**
+ * @file cadet/gnunet-service-cadet-new_paths.h
+ * @brief Information we track per path.
+ * @author Bartlomiej Polot
+ * @author Christian Grothoff
+ */
+#ifndef GNUNET_SERVICE_CADET_PATHS_H
+#define GNUNET_SERVICE_CADET_PATHS_H
+
+#include "gnunet_util_lib.h"
+#include "gnunet_dht_service.h"
+#include "gnunet-service-cadet.h"
+
+/**
+ * Create a peer path based on the result of a DHT lookup.  If we
+ * already know this path, or one that is longer, simply return NULL.
+ * Otherwise, we try to extend an existing path, or create a new one
+ * if applicable.
+ *
+ * @param get_path path of the get request
+ * @param get_path_length length of @a get_path
+ * @param put_path path of the put request
+ * @param put_path_length length of the @a put_path
+ */
+void
+GCPP_try_path_from_dht (const struct GNUNET_DHT_PathElement *get_path,
+                        unsigned int get_path_length,
+                        const struct GNUNET_DHT_PathElement *put_path,
+                        unsigned int put_path_length);
+
+
+/**
+ * We got an incoming connection, obtain the corresponding path.
+ *
+ * @param path_length number of segments on the @a path
+ * @param pids path through the network, in reverse order 
+ *             (we are at the end, at index @a path_length)
+ * @return corresponding path object
+ */
+struct CadetPeerPath *
+GCPP_get_path_from_route (unsigned int path_length,
+                          const struct GNUNET_PeerIdentity *pids);
+
+
+/**
+ * Return the length of the path.  Excludes one end of the
+ * path, so the loopback path has length 0.
+ *
+ * @param path path to return the length for
+ * @return number of peers on the path
+ */
+unsigned int
+GCPP_get_length (struct CadetPeerPath *path);
+
+
+/**
+ * Return connection to @a destination using @a path, or return
+ * NULL if no such connection exists.
+ *
+ * @param path path to traverse
+ * @param destination destination node to get to, must be on path
+ * @param off offset of @a destination on @a path
+ * @return NULL if we have no existing connection
+ *         otherwise connection from us to @a destination via @a path
+ */
+struct CadetConnection *
+GCPP_get_connection (struct CadetPeerPath *path,
+                     struct CadetPeer *destination,
+                     unsigned int off);
+
+
+/**
+ * Notify @a path that it is used for connection @a cc
+ * which ends at the path's offset @a off.
+ *
+ * @param path the path to remember the @a cc
+ * @param off the offset where the @a cc ends
+ * @param cc the connection to remember
+ */
+void
+GCPP_add_connection (struct CadetPeerPath *path,
+                     unsigned int off,
+                     struct CadetConnection *cc);
+
+
+/**
+ * Notify @a path that it is no longer used for connection @a cc which
+ * ended at the path's offset @a off.
+ *
+ * @param path the path to forget the @a cc
+ * @param off the offset where the @a cc ended
+ * @param cc the connection to forget
+ */
+void
+GCPP_del_connection (struct CadetPeerPath *path,
+                     unsigned int off,
+                     struct CadetConnection *cc);
+
+
+/**
+ * Find peer's offset on path.
+ *
+ * @param path path to search
+ * @param cp peer to look for
+ * @return offset of @a cp on @a path, or UINT_MAX if not found
+ */
+unsigned int
+GCPP_find_peer (struct CadetPeerPath *path,
+                struct CadetPeer *cp);
+
+
+/**
+ * Return how much we like keeping the path.  This is an aggregate
+ * score based on various factors, including the age of the path
+ * (older == better), and the value of this path to all of its adjacent
+ * peers.  For example, long paths that end at a peer that we have no
+ * shorter way to reach are very desirable, while long paths that end
+ * at a peer for which we have a shorter way as well are much less
+ * desirable.  Higher values indicate more valuable paths.  The
+ * returned value should be used to decide which paths to remember.
+ *
+ * @param path path to return the length for
+ * @return desirability of the path, larger is more desirable
+ */
+GNUNET_CONTAINER_HeapCostType
+GCPP_get_desirability (const struct CadetPeerPath *path);
+
+
+/**
+ * The given peer @a cp used to own this @a path.  However, it is no
+ * longer interested in maintaining it, so the path should be
+ * discarded or shortened (in case a previous peer on the path finds
+ * the path desirable).
+ *
+ * @param path the path that is being released
+ */
+void
+GCPP_release (struct CadetPeerPath *path);
+
+
+/**
+ * Obtain the peer at offset @a off in @a path.
+ *
+ * @param path peer path to inspect
+ * @param off offset to return, must be smaller than path length
+ * @return peer at offset @a off
+ */
+struct CadetPeer *
+GCPP_get_peer_at_offset (struct CadetPeerPath *path,
+                         unsigned int off);
+
+
+/**
+ * Convert a path to a human-readable string.
+ *
+ * @param path path to convert
+ * @return string, statically allocated
+ */
+const char *
+GCPP_2s (struct CadetPeerPath *p);
+
+
+#endif