+ * ATS connectivity handle.
+ */
+extern struct GNUNET_ATS_ConnectivityHandle *GST_ats_connect;
+
+/**
+ * Interface scanner determines our LAN address range(s).
+ */
+extern struct GNUNET_ATS_InterfaceScanner *GST_is;
+
+
+/**
+ * Function to call when a peer's address has changed
+ *
+ * @param cls closure
+ * @param peer peer this update is about,
+ * @param address address, NULL for disconnect notification
+ */
+typedef void
+(*GNUNET_TRANSPORT_NeighbourChangeCallback) (void *cls,
+ const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_HELLO_Address *address,
+ enum GNUNET_TRANSPORT_PeerState state,
+ struct GNUNET_TIME_Absolute state_timeout,
+ struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
+ struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out);
+
+
+/**
+ * Continuation called from a blacklist test.
+ *
+ * @param cls closure
+ * @param peer identity of peer that was tested
+ * @param address address associated with the request
+ * @param session session associated with the request
+ * @param result #GNUNET_OK if the connection is allowed,
+ * #GNUNET_NO if not,
+ * #GNUNET_SYSERR if operation was aborted
+ */
+typedef void
+(*GST_BlacklistTestContinuation) (void *cls,
+ const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_HELLO_Address *address,
+ struct GNUNET_ATS_Session *session,
+ int result);
+
+
+/**
+ * Add the given peer to the blacklist (for the given transport).
+ *
+ * @param peer peer to blacklist
+ * @param transport_name transport to blacklist for this peer, NULL for all
+ */
+void
+GST_blacklist_add_peer (const struct GNUNET_PeerIdentity *peer,
+ const char *transport_name);
+
+
+/**
+ * Handle to an active blacklist check.
+ */
+struct GST_BlacklistCheck;
+
+
+
+/**
+ * Test if a peer/transport combination is blacklisted.
+ *
+ * @param peer the identity of the peer to test
+ * @param transport_name name of the transport to test, never NULL
+ * @param cont function to call with result
+ * @param cont_cls closure for @a cont
+ * @param address address to pass back to @a cont, can be NULL
+ * @param session session to pass back to @a cont, can be NULL
+ * @return handle to the blacklist check, NULL if the decision
+ * was made instantly and @a cont was already called
+ */
+struct GST_BlacklistCheck *
+GST_blacklist_test_allowed (const struct GNUNET_PeerIdentity *peer,
+ const char *transport_name,
+ GST_BlacklistTestContinuation cont,
+ void *cont_cls,
+ const struct GNUNET_HELLO_Address *address,
+ struct GNUNET_ATS_Session *session);
+
+
+/**
+ * Abort blacklist if @a address and @a session match.
+ *
+ * @param address address used to abort matching checks
+ * @param session session used to abort matching checks
+ */
+void
+GST_blacklist_abort_matching (const struct GNUNET_HELLO_Address *address,
+ struct GNUNET_ATS_Session *session);
+
+/**
+ * Cancel a blacklist check.
+ *
+ * @param bc check to cancel
+ */
+void
+GST_blacklist_test_cancel (struct GST_BlacklistCheck *bc);
+
+
+/**
+ * Function called by the transport for each received message.
+ *
+ * @param cls closure, const char* with the name of the plugin we received the message from
+ * @param address address and (claimed) identity of the other peer
+ * @param session identifier used for this session (NULL for plugins
+ * that do not offer bi-directional communication to the sender
+ * using the same "connection")
+ * @param message the message, NULL if we only care about
+ * learning about the delay until we should receive again
+ * @return how long the plugin should wait until receiving more data
+ * (plugins that do not support this, can ignore the return value)