/*
This file is part of GNUnet.
- Copyright (C) 2013 GNUnet e.V.
+ 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 General Public License as published
/**
* @file cadet/gnunet-service-cadet_peer.h
- * @brief cadet service; dealing with remote peers
+ * @brief Information we track per peer.
* @author Bartlomiej Polot
- *
- * All functions in this file should use the prefix GMP (Gnunet Cadet Peer)
+ * @author Christian Grothoff
*/
-
#ifndef GNUNET_SERVICE_CADET_PEER_H
#define GNUNET_SERVICE_CADET_PEER_H
-#ifdef __cplusplus
-extern "C"
-{
-#if 0 /* keep Emacsens' auto-indent happy */
-}
-#endif
-#endif
-
-#include "platform.h"
-#include "gnunet_util_lib.h"
-#include "cadet_path.h"
+#include "gnunet-service-cadet.h"
+#include "gnunet_hello_lib.h"
-/**
- * Struct containing all information regarding a given peer
- */
-struct CadetPeer;
-
-/**
- * Handle to queued messages on a peer level.
- */
-struct CadetPeerQueue;
-
-#include "gnunet-service-cadet_connection.h"
-
-
-/**
- * Callback called when a queued message is sent.
- *
- * @param cls Closure.
- * @param c Connection this message was on.
- * @param fwd Was this a FWD going message?
- * @param sent Was it really sent? (Could have been canceled)
- * @param type Type of message sent.
- * @param payload_type Type of payload, if applicable.
- * @param pid Message ID, or 0 if not applicable (create, destroy, etc).
- * @param size Size of the message.
- * @param wait Time spent waiting for core (only the time for THIS message)
- */
-typedef void
-(*GCP_sent) (void *cls,
- struct CadetConnection *c,
- int fwd,
- int sent,
- uint16_t type,
- uint16_t payload_type,
- struct CadetEncryptedMessageIdentifier pid,
- size_t size,
- struct GNUNET_TIME_Relative wait);
/**
- * Peer path iterator.
+ * Get the static string for a peer ID.
*
- * @param cls Closure.
- * @param peer Peer this path is towards.
- * @param path Path itself
- * @return #GNUNET_YES if should keep iterating.
- * #GNUNET_NO otherwise.
- */
-typedef int
-(*GCP_path_iterator) (void *cls,
- struct CadetPeer *peer,
- struct CadetPeerPath *path);
-
-
-/******************************************************************************/
-/******************************** API ***********************************/
-/******************************************************************************/
-
-/**
- * Initialize peer subsystem.
+ * @param peer Peer.
*
- * @param c Configuration.
- */
-void
-GCP_init (const struct GNUNET_CONFIGURATION_Handle *c);
-
-/**
- * Shut down the peer subsystem.
+ * @return Static string for it's ID.
*/
-void
-GCP_shutdown (void);
+const char *
+GCP_2s (const struct CadetPeer *peer);
/**
- * Retrieve the CadetPeer stucture associated with the peer. Optionally create
- * one and insert it in the appropriate structures if the peer is not known yet.
+ * Retrieve the CadetPeer stucture associated with the
+ * peer. Optionally create one and insert it in the appropriate
+ * structures if the peer is not known yet.
*
* @param peer_id Full identity of the peer.
* @param create #GNUNET_YES if a new peer should be created if unknown.
- * #GNUNET_NO otherwise.
- *
+ * #GNUNET_NO to return NULL if peer is unknown.
* @return Existing or newly created peer structure.
* NULL if unknown and not requested @a create
*/
struct CadetPeer *
-GCP_get (const struct GNUNET_PeerIdentity *peer_id, int create);
+GCP_get (const struct GNUNET_PeerIdentity *peer_id,
+ int create);
/**
- * Retrieve the CadetPeer stucture associated with the peer. Optionally create
- * one and insert it in the appropriate structures if the peer is not known yet.
- *
- * @param peer Short identity of the peer.
- * @param create #GNUNET_YES if a new peer should be created if unknown.
- * #GNUNET_NO otherwise.
+ * Calculate how desirable a path is for @a cp if
+ * @a cp is at offset @a off in the path.
*
- * @return Existing or newly created peer structure.
- * NULL if unknown and not requested @a create
+ * @param cp a peer reachable via a path
+ * @param off offset of @a cp in a path
+ * @return score how useful a path is to reach @a cp,
+ * positive scores mean path is more desirable
*/
-struct CadetPeer *
-GCP_get_short (const GNUNET_PEER_Id peer, int create);
+double
+GCP_get_desirability_of_path (struct CadetPeer *cp,
+ unsigned int off);
/**
- * Try to establish a new connection to this peer (in its tunnel).
- * If the peer doesn't have any path to it yet, try to get one.
- * If the peer already has some path, send a CREATE CONNECTION towards it.
- *
- * @param peer Peer to connect to.
- */
-void
-GCP_connect (struct CadetPeer *peer);
-
-/**
- * @brief Send a message to another peer (using CORE).
+ * Obtain the peer identity for a `struct CadetPeer`.
*
- * @param peer Peer towards which to queue the message.
- * @param message Message to send.
- * @param payload_type Type of the message's payload, for debug messages.
- * 0 if the message is a retransmission (unknown payload).
- * UINT16_MAX if the message does not have payload.
- * @param payload_id ID of the payload (MID, ACK #, etc)
- * @param c Connection this message belongs to (can be NULL).
- * @param fwd Is this a message going root->dest? (FWD ACK are NOT FWD!)
- * @param cont Continuation to be called once CORE has sent the message.
- * @param cont_cls Closure for @c cont.
+ * @param cp our peer handle
+ * @return the peer identity
*/
-struct CadetPeerQueue *
-GCP_send (struct CadetPeer *peer,
- const struct GNUNET_MessageHeader *message,
- uint16_t payload_type,
- struct CadetEncryptedMessageIdentifier payload_id,
- struct CadetConnection *c,
- int fwd,
- GCP_sent cont,
- void *cont_cls);
+const struct GNUNET_PeerIdentity *
+GCP_get_id (struct CadetPeer *cp);
-/**
- * Cancel sending a message. Message must have been sent with
- * #GCP_send before. May not be called after the notify sent
- * callback has been called.
- *
- * It does NOT call the continuation given to #GCP_send.
- *
- * @param q Queue handle to cancel
- */
-void
-GCP_send_cancel (struct CadetPeerQueue *q);
/**
- * Set tunnel.
+ * Iterate over all known peers.
*
- * @param peer Peer.
- * @param t Tunnel.
+ * @param iter Iterator.
+ * @param cls Closure for @c iter.
*/
void
-GCP_set_tunnel (struct CadetPeer *peer, struct CadetTunnel *t);
+GCP_iterate_all (GNUNET_CONTAINER_PeerMapIterator iter,
+ void *cls);
/**
- * Check whether there is a direct (core level) connection to peer.
- *
- * @param peer Peer to check.
+ * Count the number of known paths toward the peer.
*
- * @return #GNUNET_YES if there is a direct connection.
+ * @param cp Peer to get path info.
+ * @return Number of known paths.
*/
-int
-GCP_is_neighbor (const struct CadetPeer *peer);
+unsigned int
+GCP_count_paths (const struct CadetPeer *cp);
/**
- * Create and initialize a new tunnel towards a peer, in case it has none.
+ * Drop all paths owned by this peer, and do not
+ * allow new ones to be added: We are shutting down.
*
- * Does not generate any traffic, just creates the local data structures.
- *
- * @param peer Peer towards which to create the tunnel.
+ * @param cp peer to drop paths to
*/
void
-GCP_add_tunnel (struct CadetPeer *peer);
+GCP_drop_owned_paths (struct CadetPeer *cp);
/**
- * Add a connection to a neighboring peer.
- *
- * Store that the peer is the first hop of the connection in one
- * direction and that on peer disconnect the connection must be
- * notified and destroyed, for it will no longer be valid.
+ * Peer path iterator.
*
- * @param peer Peer to add connection to.
- * @param c Connection to add.
- * @param pred #GNUNET_YES if we are predecessor, #GNUNET_NO if we are successor
+ * @param cls Closure.
+ * @param path Path itself
+ * @param off offset of the target peer in @a path
+ * @return #GNUNET_YES if should keep iterating.
+ * #GNUNET_NO otherwise.
*/
-void
-GCP_add_connection (struct CadetPeer *peer,
- struct CadetConnection *c,
- int pred);
+typedef int
+(*GCP_PathIterator) (void *cls,
+ struct CadetPeerPath *path,
+ unsigned int off);
/**
- * Add the path to the peer and update the path used to reach it in case this
- * is the shortest.
- *
- * @param peer Destination peer to add the path to.
- * @param path New path to add. Last peer must be the peer in arg 1.
- * Path will be either used of freed if already known.
- * @param trusted Do we trust that this path is real?
+ * Iterate over the paths to a peer.
*
- * @return path if path was taken, pointer to existing duplicate if exists
- * NULL on error.
+ * @param cp Peer to get path info.
+ * @param callback Function to call for every path.
+ * @param callback_cls Closure for @a callback.
+ * @return Number of iterated paths.
*/
-struct CadetPeerPath *
-GCP_add_path (struct CadetPeer *peer,
- struct CadetPeerPath *p,
- int trusted);
+unsigned int
+GCP_iterate_paths (struct CadetPeer *cp,
+ GCP_PathIterator callback,
+ void *callback_cls);
/**
- * Add the path to the origin peer and update the path used to reach it in case
- * this is the shortest.
- * The path is given in peer_info -> destination, therefore we turn the path
- * upside down first.
- *
- * @param peer Peer to add the path to, being the origin of the path.
- * @param path New path to add after being inversed.
- * Path will be either used or freed.
- * @param trusted Do we trust that this path is real?
+ * Iterate over the paths to @a peer where
+ * @a peer is at distance @a dist from us.
*
- * @return path if path was taken, pointer to existing duplicate if exists
- * NULL on error.
+ * @param cp Peer to get path info.
+ * @param dist desired distance of @a peer to us on the path
+ * @param callback Function to call for every path.
+ * @param callback_cls Closure for @a callback.
+ * @return Number of iterated paths.
*/
-struct CadetPeerPath *
-GCP_add_path_to_origin (struct CadetPeer *peer,
- struct CadetPeerPath *path,
- int trusted);
+unsigned int
+GCP_iterate_paths_at (struct CadetPeer *cp,
+ unsigned int dist,
+ GCP_PathIterator callback,
+ void *callback_cls);
+
/**
- * Adds a path to the info of all the peers in the path
+ * Remove an entry from the DLL of all of the paths that this peer is on.
*
- * @param p Path to process.
- * @param confirmed Whether we know if the path works or not.
+ * @param cp peer to modify
+ * @param entry an entry on a path
+ * @param off offset of this peer on the path
*/
void
-GCP_add_path_to_all (const struct CadetPeerPath *p, int confirmed);
+GCP_path_entry_remove (struct CadetPeer *cp,
+ struct CadetPeerPathEntry *entry,
+ unsigned int off);
/**
- * Remove any path to the peer that has the extact same peers as the one given.
+ * Add an entry to the DLL of all of the paths that this peer is on.
*
- * @param peer Peer to remove the path from.
- * @param path Path to remove. Is always destroyed .
+ * @param cp peer to modify
+ * @param entry an entry on a path
+ * @param off offset of this peer on the path
*/
void
-GCP_remove_path (struct CadetPeer *peer,
- struct CadetPeerPath *path);
+GCP_path_entry_add (struct CadetPeer *cp,
+ struct CadetPeerPathEntry *entry,
+ unsigned int off);
/**
- * Check that we are aware of a connection from a neighboring peer.
+ * Get the tunnel towards a peer.
*
- * @param peer Peer to the connection is with
- * @param c Connection that should be in the map with this peer.
+ * @param cp Peer to get from.
+ * @param create #GNUNET_YES to create a tunnel if we do not have one
+ * @return Tunnel towards peer.
*/
-void
-GCP_check_connection (const struct CadetPeer *peer,
- const struct CadetConnection *c);
+struct CadetTunnel *
+GCP_get_tunnel (struct CadetPeer *cp,
+ int create);
/**
- * Remove a connection from a neighboring peer.
+ * The tunnel to the given peer no longer exists, remove it from our
+ * data structures, and possibly clean up the peer itself.
*
- * @param peer Peer to remove connection from.
- * @param c Connection to remove.
+ * @param cp the peer affected
+ * @param t the dead tunnel
*/
void
-GCP_remove_connection (struct CadetPeer *peer,
- const struct CadetConnection *c);
+GCP_drop_tunnel (struct CadetPeer *cp,
+ struct CadetTunnel *t);
/**
- * Start the DHT search for new paths towards the peer: we don't have
- * enough good connections.
+ * Try adding a @a path to this @a cp. If the peer already
+ * has plenty of paths, return NULL.
*
- * @param peer Destination peer.
+ * @param cp peer to which the @a path leads to
+ * @param path a path looking for an owner; may not be fully initialized yet!
+ * @param off offset of @a cp in @a path
+ * @param force for attaching the path
+ * @return NULL if this peer does not care to become a new owner,
+ * otherwise the node in the peer's path heap for the @a path.
*/
-void
-GCP_start_search (struct CadetPeer *peer);
+struct GNUNET_CONTAINER_HeapNode *
+GCP_attach_path (struct CadetPeer *cp,
+ struct CadetPeerPath *path,
+ unsigned int off,
+ int force);
/**
- * Stop the DHT search for new paths towards the peer: we already have
- * enough good connections.
+ * This peer can no longer own @a path as the path
+ * has been extended and a peer further down the line
+ * is now the new owner.
*
- * @param peer Destination peer.
+ * @param cp old owner of the @a path
+ * @param path path where the ownership is lost
+ * @param hn note in @a cp's path heap that must be deleted
*/
void
-GCP_stop_search (struct CadetPeer *peer);
+GCP_detach_path (struct CadetPeer *cp,
+ struct CadetPeerPath *path,
+ struct GNUNET_CONTAINER_HeapNode *hn);
/**
- * Get the Full ID of a peer.
+ * Add a @a connection to this @a cp.
*
- * @param peer Peer to get from.
- *
- * @return Full ID of peer.
+ * @param cp peer via which the @a connection goes
+ * @param cc the connection to add
*/
-const struct GNUNET_PeerIdentity *
-GCP_get_id (const struct CadetPeer *peer);
+void
+GCP_add_connection (struct CadetPeer *cp,
+ struct CadetConnection *cc);
/**
- * Get the Short ID of a peer.
- *
- * @param peer Peer to get from.
+ * Remove a @a connection that went via this @a cp.
*
- * @return Short ID of peer.
+ * @param cp peer via which the @a connection went
+ * @param cc the connection to remove
*/
-GNUNET_PEER_Id
-GCP_get_short_id (const struct CadetPeer *peer);
+void
+GCP_remove_connection (struct CadetPeer *cp,
+ struct CadetConnection *cc);
/**
- * Get the tunnel towards a peer.
+ * We got a HELLO for a @a cp, remember it, and possibly
+ * trigger adequate actions (like trying to connect).
*
- * @param peer Peer to get from.
- *
- * @return Tunnel towards peer.
+ * @param cp the peer we got a HELLO for
+ * @param hello the HELLO to remember
*/
-struct CadetTunnel *
-GCP_get_tunnel (const struct CadetPeer *peer);
+void
+GCP_set_hello (struct CadetPeer *cp,
+ const struct GNUNET_HELLO_Message *hello);
/**
- * Set the hello message.
- *
- * @param peer Peer whose message to set.
- * @param hello Hello message.
+ * Clean up all entries about all peers.
+ * Must only be called after all tunnels, CORE-connections and
+ * connections are down.
*/
void
-GCP_set_hello (struct CadetPeer *peer,
- const struct GNUNET_HELLO_Message *hello);
+GCP_destroy_all_peers (void);
/**
- * Get the hello message.
- *
- * @param peer Peer whose message to get.
+ * Data structure used to track whom we have to notify about changes
+ * in our ability to transmit to a given peer.
*
- * @return Hello message.
+ * All queue managers will be given equal chance for sending messages
+ * to @a cp. This construct this guarantees fairness for access to @a
+ * cp among the different message queues. Each connection or route
+ * will have its respective message queue managers for each direction.
*/
-struct GNUNET_HELLO_Message *
-GCP_get_hello (struct CadetPeer *peer);
+struct GCP_MessageQueueManager;
/**
- * Try to connect to a peer on TRANSPORT level.
+ * Function to call with updated message queue object.
*
- * @param peer Peer to whom to connect.
+ * @param cls closure
+ * @param available #GNUNET_YES if sending is now possible,
+ * #GNUNET_NO if sending is no longer possible
+ * #GNUNET_SYSERR if sending is no longer possible
+ * and the last envelope was discarded
*/
-void
-GCP_try_connect (struct CadetPeer *peer);
+typedef void
+(*GCP_MessageQueueNotificationCallback)(void *cls,
+ int available);
+
/**
- * Notify a peer that a link between two other peers is broken. If any path
- * used that link, eliminate it.
+ * Start message queue change notifications. Will create a new slot
+ * to manage the message queue to the given @a cp.
*
- * @param peer Peer affected by the change.
- * @param peer1 Peer whose link is broken.
- * @param peer2 Peer whose link is broken.
+ * @param cp peer to notify for
+ * @param cb function to call if mq becomes available or unavailable
+ * @param cb_cls closure for @a cb
+ * @return handle to cancel request
*/
-void
-GCP_notify_broken_link (struct CadetPeer *peer,
- const struct GNUNET_PeerIdentity *peer1,
- const struct GNUNET_PeerIdentity *peer2);
+struct GCP_MessageQueueManager *
+GCP_request_mq (struct CadetPeer *cp,
+ GCP_MessageQueueNotificationCallback cb,
+ void *cb_cls);
/**
- * Count the number of known paths toward the peer.
+ * Test if @a cp has a core-level connection
*
- * @param peer Peer to get path info.
- *
- * @return Number of known paths.
+ * @param cp peer to test
+ * @return #GNUNET_YES if @a cp has a core-level connection
*/
-unsigned int
-GCP_count_paths (const struct CadetPeer *peer);
+int
+GCP_has_core_connection (struct CadetPeer *cp);
+
/**
- * Iterate over the paths to a peer.
+ * Send the message in @a env via a @a mqm. Must only be called at
+ * most once after the respective
+ * #GCP_MessageQueueNotificationCallback was called with `available`
+ * set to #GNUNET_YES, and not after the callback was called with
+ * `available` set to #GNUNET_NO or #GNUNET_SYSERR.
*
- * @param peer Peer to get path info.
- * @param callback Function to call for every path.
- * @param cls Closure for @a callback.
- *
- * @return Number of iterated paths.
+ * @param mqm message queue manager for the transmission
+ * @param env envelope with the message to send; must NOT
+ * yet have a #GNUNET_MQ_notify_sent() callback attached to it
*/
-unsigned int
-GCP_iterate_paths (struct CadetPeer *peer,
- GCP_path_iterator callback,
- void *cls);
+void
+GCP_send (struct GCP_MessageQueueManager *mqm,
+ struct GNUNET_MQ_Envelope *env);
/**
- * Iterate all known peers.
+ * Send the message in @a env to @a cp, overriding queueing logic.
+ * This function should only be used to send error messages outside
+ * of flow and congestion control, similar to ICMP. Note that
+ * the envelope may be silently discarded as well.
*
- * @param iter Iterator.
- * @param cls Closure for @c iter.
+ * @param cp peer to send the message to
+ * @param env envelope with the message to send
*/
void
-GCP_iterate_all (GNUNET_CONTAINER_PeerMapIterator iter,
- void *cls);
+GCP_send_ooo (struct CadetPeer *cp,
+ struct GNUNET_MQ_Envelope *env);
/**
- * Get the static string for a peer ID.
- *
- * @param peer Peer.
+ * Stops message queue change notifications and sends a last message.
+ * In practice, this is implemented by sending that @a last_env
+ * message immediately (if any), ignoring queue order.
*
- * @return Static string for it's ID.
+ * @param mqm handle matching request to cancel
+ * @param last_env final message to transmit, or NULL
*/
-const char *
-GCP_2s (const struct CadetPeer *peer);
+void
+GCP_request_mq_cancel (struct GCP_MessageQueueManager *mqm,
+ struct GNUNET_MQ_Envelope *last_env);
/**
- * Log all kinds of info about a peer.
+ * Set the message queue to @a mq for peer @a cp and notify watchers.
*
- * @param peer Peer.
+ * @param cp peer to modify
+ * @param mq message queue to set (can be NULL)
*/
void
-GCP_debug (const struct CadetPeer *p,
- enum GNUNET_ErrorType level);
-
+GCP_set_mq (struct CadetPeer *cp,
+ struct GNUNET_MQ_Handle *mq);
-#if 0 /* keep Emacsens' auto-indent happy */
-{
-#endif
-#ifdef __cplusplus
-}
-#endif
-/* ifndef GNUNET_CADET_SERVICE_PEER_H */
#endif
-/* end of gnunet-cadet-service_peer.h */