#include "gnunet_util_lib.h"
+
+/**
+ * All the states a connection can be in.
+ */
+enum MeshConnectionState
+{
+ /**
+ * Uninitialized status, should never appear in operation.
+ */
+ MESH_CONNECTION_NEW,
+
+ /**
+ * Connection create message sent, waiting for ACK.
+ */
+ MESH_CONNECTION_SENT,
+
+ /**
+ * Connection ACK sent, waiting for ACK.
+ */
+ MESH_CONNECTION_ACK,
+
+ /**
+ * Connection confirmed, ready to carry traffic.
+ */
+ MESH_CONNECTION_READY,
+
+ /**
+ * Connection to be destroyed, just waiting to empty queues.
+ */
+ MESH_CONNECTION_DESTROYED,
+};
+
+
/**
* Struct containing all information regarding a connection to a peer.
*/
struct MeshConnection;
+/**
+ * Handle for messages queued but not yet sent.
+ */
+struct MeshConnectionQueue;
+
+#include "mesh_path.h"
+#include "gnunet-service-mesh_channel.h"
+#include "gnunet-service-mesh_peer.h"
+
+
+
+/**
+ * Callback called when a queued message is sent.
+ *
+ * @param cls Closure.
+ * @param c Connection this message was on.
+ * @param type Type of message sent.
+ * @param fwd Was this a FWD going message?
+ * @param size Size of the message.
+ */
+typedef void (*GMC_sent) (void *cls,
+ struct MeshConnection *c,
+ struct MeshConnectionQueue *q,
+ uint16_t type, int fwd, size_t size);
+
+/**
+ * Core handler for connection creation.
+ *
+ * @param cls Closure (unused).
+ * @param peer Sender (neighbor).
+ * @param message Message.
+ *
+ * @return GNUNET_OK to keep the connection open,
+ * GNUNET_SYSERR to close it (signal serious error)
+ */
+int
+GMC_handle_create (void *cls, const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message);
+
+/**
+ * Core handler for path confirmations.
+ *
+ * @param cls closure
+ * @param message message
+ * @param peer peer identity this notification is about
+ *
+ * @return GNUNET_OK to keep the connection open,
+ * GNUNET_SYSERR to close it (signal serious error)
+ */
+int
+GMC_handle_confirm (void *cls, const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message);
+
+/**
+ * Core handler for notifications of broken paths
+ *
+ * @param cls Closure (unused).
+ * @param id Peer identity of sending neighbor.
+ * @param message Message.
+ *
+ * @return GNUNET_OK to keep the connection open,
+ * GNUNET_SYSERR to close it (signal serious error)
+ */
+int
+GMC_handle_broken (void* cls,
+ const struct GNUNET_PeerIdentity* id,
+ const struct GNUNET_MessageHeader* message);
+
+/**
+ * Core handler for tunnel destruction
+ *
+ * @param cls Closure (unused).
+ * @param peer Peer identity of sending neighbor.
+ * @param message Message.
+ *
+ * @return GNUNET_OK to keep the connection open,
+ * GNUNET_SYSERR to close it (signal serious error)
+ */
+int
+GMC_handle_destroy (void *cls, const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message);
+
+/**
+ * Core handler for encrypted mesh network traffic (channel mgmt, data).
+ *
+ * @param cls Closure (unused).
+ * @param message Message received.
+ * @param peer Peer who sent the message.
+ *
+ * @return GNUNET_OK to keep the connection open,
+ * GNUNET_SYSERR to close it (signal serious error)
+ */
+int
+GMC_handle_encrypted (void *cls, const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message);
+
+/**
+ * Core handler for key exchange traffic (ephemeral key, ping, pong).
+ *
+ * @param cls Closure (unused).
+ * @param message Message received.
+ * @param peer Peer who sent the message.
+ *
+ * @return GNUNET_OK to keep the connection open,
+ * GNUNET_SYSERR to close it (signal serious error)
+ */
+int
+GMC_handle_kx (void *cls, const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message);
+
+/**
+ * Core handler for mesh network traffic point-to-point acks.
+ *
+ * @param cls closure
+ * @param message message
+ * @param peer peer identity this notification is about
+ *
+ * @return GNUNET_OK to keep the connection open,
+ * GNUNET_SYSERR to close it (signal serious error)
+ */
+int
+GMC_handle_ack (void *cls, const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message);
+
+/**
+ * Core handler for mesh network traffic point-to-point ack polls.
+ *
+ * @param cls closure
+ * @param message message
+ * @param peer peer identity this notification is about
+ *
+ * @return GNUNET_OK to keep the connection open,
+ * GNUNET_SYSERR to close it (signal serious error)
+ */
+int
+GMC_handle_poll (void *cls, const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message);
+
+/**
+ * Core handler for mesh keepalives.
+ *
+ * @param cls closure
+ * @param message message
+ * @param peer peer identity this notification is about
+ * @return GNUNET_OK to keep the connection open,
+ * GNUNET_SYSERR to close it (signal serious error)
+ *
+ * TODO: Check who we got this from, to validate route.
+ */
+int
+GMC_handle_keepalive (void *cls, const struct GNUNET_PeerIdentity *peer,
+ const struct GNUNET_MessageHeader *message);
+
+/**
+ * Send an ACK on the appropriate connection/channel, depending on
+ * the direction and the position of the peer.
+ *
+ * @param c Which connection to send the hop-by-hop ACK.
+ * @param fwd Is this a fwd ACK? (will go dest->root).
+ * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
+ */
+void
+GMC_send_ack (struct MeshConnection *c, int fwd, int force);
+
/**
* Initialize the connections subsystem
*
/**
* Create a connection.
*
- * @param cid Connection ID.
+ * @param cid Connection ID (either created locally or imposed remotely).
+ * @param t Tunnel this connection belongs to (or NULL);
+ * @param p Path this connection has to use.
+ * @param own_pos Own position in the @c p path.
+ *
+ * @return Newly created connection, NULL in case of error (own id not in path).
*/
struct MeshConnection *
-GMC_new (const struct GNUNET_HashCode *cid);
+GMC_new (const struct GNUNET_HashCode *cid,
+ struct MeshTunnel3 *t,
+ struct MeshPeerPath *p,
+ unsigned int own_pos);
/**
- * Connection is no longer needed: destroy it and remove from tunnel.
+ * Connection is no longer needed: destroy it.
+ *
+ * Cancels all pending traffic (including possible DESTROY messages), all
+ * maintenance tasks and removes the connection from neighbor peers and tunnel.
*
* @param c Connection to destroy.
*/
GMC_destroy (struct MeshConnection *c);
/**
- * Count connections in a DLL.
+ * Get the connection ID.
+ *
+ * @param c Connection to get the ID from.
+ *
+ * @return ID of the connection.
+ */
+const struct GNUNET_HashCode *
+GMC_get_id (const struct MeshConnection *c);
+
+/**
+ * Get the connection path.
+ *
+ * @param c Connection to get the path from.
+ *
+ * @return path used by the connection.
+ */
+const struct MeshPeerPath *
+GMC_get_path (const struct MeshConnection *c);
+
+/**
+ * Get the connection state.
+ *
+ * @param c Connection to get the state from.
+ *
+ * @return state of the connection.
+ */
+enum MeshConnectionState
+GMC_get_state (const struct MeshConnection *c);
+
+/**
+ * Get the connection tunnel.
+ *
+ * @param c Connection to get the tunnel from.
+ *
+ * @return tunnel of the connection.
+ */
+struct MeshTunnel3 *
+GMC_get_tunnel (const struct MeshConnection *c);
+
+/**
+ * Get free buffer space in a connection.
+ *
+ * @param c Connection.
+ * @param fwd Is query about FWD traffic?
+ *
+ * @return Free buffer space [0 - max_msgs_queue/max_connections]
*/
unsigned int
-GMC_count (const struct MeshConnection *head);
+GMC_get_buffer (struct MeshConnection *c, int fwd);
+
+/**
+ * Get how many messages have we allowed to send to us from a direction.
+ *
+ * @param c Connection.
+ * @param fwd Are we asking about traffic from FWD (BCK messages)?
+ *
+ * @return last_ack_sent - last_pid_recv
+ */
+unsigned int
+GMC_get_allowed (struct MeshConnection *c, int fwd);
+
+/**
+ * Get messages queued in a connection.
+ *
+ * @param c Connection.
+ * @param fwd Is query about FWD traffic?
+ *
+ * @return Number of messages queued.
+ */
+unsigned int
+GMC_get_qn (struct MeshConnection *c, int fwd);
+
+/**
+ * Allow the connection to advertise a buffer of the given size.
+ *
+ * The connection will send an @c fwd ACK message (so: in direction !fwd)
+ * allowing up to last_pid_recv + buffer.
+ *
+ * @param c Connection.
+ * @param buffer How many more messages the connection can accept.
+ * @param fwd Is this about FWD traffic? (The ack will go dest->root).
+ */
+void
+GMC_allow (struct MeshConnection *c, unsigned int buffer, int fwd);
/**
* Send FWD keepalive packets for a connection.
/**
- * Change the tunnel state.
+ * Notify other peers on a connection of a broken link. Mark connections
+ * to destroy after all traffic has been sent.
*
- * @param c Connection whose state to change.
- * @param state New state.
+ * @param c Connection on which there has been a disconnection.
+ * @param peer Peer that disconnected.
*/
void
-GMC_change_state (struct MeshConnection* c, enum MeshConnectionState state);
+GMC_notify_broken (struct MeshConnection *c,
+ struct MeshPeer *peer);
/**
- * Iterator to notify all connections of a broken link. Mark connections
- * to destroy after all traffic has been sent.
+ * Is this peer the first one on the connection?
*
- * @param cls Closure (peer disconnected).
- * @param key Current key code (tid).
- * @param value Value in the hash map (connection).
+ * @param c Connection.
+ * @param fwd Is this about fwd traffic?
*
- * @return GNUNET_YES if we should continue to iterate,
- * GNUNET_NO if not.
+ * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
*/
int
-GMC_notify_broken (void *cls,
- const struct GNUNET_HashCode *key,
- void *value);
+GMC_is_origin (struct MeshConnection *c, int fwd);
/**
- * @brief Queue and pass message to core when possible.
+ * Is this peer the last one on the connection?
*
- * @param cls Closure (@c type dependant). It will be used by queue_send to
- * build the message to be sent if not already prebuilt.
- * @param type Type of the message, 0 for a raw message.
- * @param size Size of the message.
- * @param c Connection this message belongs to (cannot be NULL).
- * @param ch Channel this message belongs to, if applicable (otherwise NULL).
- * @param fwd Is this a message going root->dest? (FWD ACK are NOT FWD!)
+ * @param c Connection.
+ * @param fwd Is this about fwd traffic?
+ * Note that the ROOT is the terminal for BCK traffic!
+ *
+ * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
*/
-void
-GMC_queue_add (void* cls,
- uint16_t type,
- size_t size,
- struct MeshConnection* c,
- struct MeshChannel* ch,
- int fwd);
+int
+GMC_is_terminal (struct MeshConnection *c, int fwd);
+/**
+ * See if we are allowed to send by the next hop in the given direction.
+ *
+ * @param c Connection.
+ * @param fwd Is this about fwd traffic?
+ *
+ * @return #GNUNET_YES in case it's OK to send.
+ */
+int
+GMC_is_sendable (struct MeshConnection *c, int fwd);
/**
- * Free a transmission that was already queued with all resources
- * associated to the request.
+ * Cancel a previously sent message while it's in the queue.
+ *
+ * ONLY can be called before the continuation given to the send function
+ * is called. Once the continuation is called, the message is no longer in the
+ * queue.
*
- * @param queue Queue handler to cancel.
- * @param clear_cls Is it necessary to free associated cls?
+ * @param q Handle to the queue.
*/
void
-GMC_queue_destroy (struct MeshPeerQueue *queue, int clear_cls);
-
+GMC_cancel (struct MeshConnectionQueue *q);
/**
- * Core callback to write a queued packet to core buffer
+ * Sends an already built message on a connection, properly registering
+ * all used resources.
*
- * @param cls Closure (peer info).
- * @param size Number of bytes available in buf.
- * @param buf Where the to write the message.
+ * @param message Message to send. Function makes a copy of it.
+ * If message is not hop-by-hop, decrements TTL of copy.
+ * @param c Connection on which this message is transmitted.
+ * @param fwd Is this a fwd message?
+ * @param force Force the connection to accept the message (buffer overfill).
+ * @param cont Continuation called once message is sent. Can be NULL.
+ * @param cont_cls Closure for @c cont.
*
- * @return number of bytes written to buf
+ * @return Handle to cancel the message before it's sent.
+ * NULL on error or if @c cont is NULL.
+ * Invalid on @c cont call.
*/
-size_t
-GMC_queue_send (void *cls, size_t size, void *buf);
-
+struct MeshConnectionQueue *
+GMC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
+ struct MeshConnection *c, int fwd, int force,
+ GMC_sent cont, void *cont_cls);
+/**
+ * Sends a CREATE CONNECTION message for a path to a peer.
+ * Changes the connection and tunnel states if necessary.
+ *
+ * @param connection Connection to create.
+ */
+void
+GMC_send_create (struct MeshConnection *connection);
/**
- * Is this peer the first one on the connection?
+ * Send a message to all peers in this connection that the connection
+ * is no longer valid.
*
- * @param c Connection.
- * @param fwd Is this about fwd traffic?
+ * If some peer should not receive the message, it should be zero'ed out
+ * before calling this function.
*
- * @return GNUNET_YES if origin, GNUNET_NO if relay/terminal.
+ * @param c The connection whose peers to notify.
*/
-int
-GMC_is_origin (struct MeshConnection *c, int fwd);
+void
+GMC_send_destroy (struct MeshConnection *c);
/**
- * Is this peer the last one on the connection?
+ * @brief Start a polling timer for the connection.
*
- * @param c Connection.
- * @param fwd Is this about fwd traffic?
- * Note that the ROOT is the terminal for BCK traffic!
+ * When a neighbor does not accept more traffic on the connection it could be
+ * caused by a simple congestion or by a lost ACK. Polling enables to check
+ * for the lastest ACK status for a connection.
*
- * @return GNUNET_YES if terminal, GNUNET_NO if relay/origin.
+ * @param c Connection.
+ * @param fwd Should we poll in the FWD direction?
*/
-int
-GMC_is_terminal (struct MeshConnection *c, int fwd);
+void
+GMC_start_poll (struct MeshConnection *c, int fwd);
+/**
+ * @brief Stop polling a connection for ACKs.
+ *
+ * Once we have enough ACKs for future traffic, polls are no longer necessary.
+ *
+ * @param c Connection.
+ * @param fwd Should we stop the poll in the FWD direction?
+ */
+void
+GMC_stop_poll (struct MeshConnection *c, int fwd);
+
+/**
+ * Get a (static) string for a connection.
+ *
+ * @param c Connection.
+ */
+const char *
+GMC_2s (const struct MeshConnection *c);
#if 0 /* keep Emacsens' auto-indent happy */
{
/* ifndef GNUNET_SERVICE_MESH_CONNECTION_H */
#endif
-/* end of gnunet-service-mesh_connection.h */
\ No newline at end of file
+/* end of gnunet-service-mesh_connection.h */
projects / oweals / gnunet.git / blobdiff