/* This file is part of GNUnet. (C) 2009, 2010, 2011, 2012, 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 include/gnunet_mesh_service.h * @brief mesh service; establish tunnels to distant peers * @author Christian Grothoff */ #ifndef GNUNET_MESH_SERVICE_H #define GNUNET_MESH_SERVICE_H #ifdef __cplusplus extern "C" { #if 0 /* keep Emacsens' auto-indent happy */ } #endif #endif #include "gnunet_util_lib.h" #include "gnunet_transport_service.h" /** * Version number of GNUnet-mesh API. */ #define GNUNET_MESH_VERSION 0x00000001 /** * Opaque handle to the service. */ struct GNUNET_MESH_Handle; /** * Opaque handle to a tunnel. */ struct GNUNET_MESH_Tunnel; /** * Functions with this signature are called whenever a message is * received. * * @param cls closure (set from GNUNET_MESH_connect) * @param tunnel connection to the other end * @param tunnel_ctx place to store local state associated with the tunnel * @param sender who sent the message * @param message the actual message * @return GNUNET_OK to keep the connection open, * GNUNET_SYSERR to close it (signal serious error) */ typedef int (*GNUNET_MESH_MessageCallback) (void *cls, struct GNUNET_MESH_Tunnel * tunnel, void **tunnel_ctx, const struct GNUNET_PeerIdentity * sender, const struct GNUNET_MessageHeader * message); /** * Message handler. Each struct specifies how to handle on particular * type of message received. */ struct GNUNET_MESH_MessageHandler { /** * Function to call for messages of "type". */ GNUNET_MESH_MessageCallback callback; /** * Type of the message this handler covers. */ uint16_t type; /** * Expected size of messages of this type. Use 0 for variable-size. * If non-zero, messages of the given type will be discarded if they * do not have the right size. */ uint16_t expected_size; }; /** * Method called whenever another peer has added us to a tunnel * the other peer initiated. * Only called (once) upon reception of data with a message type which was * subscribed to in GNUNET_MESH_connect. A call to GNUNET_MESH_tunnel_destroy * causes te tunnel to be ignored and no further notifications are sent about * the same tunnel. * * @param cls closure * @param tunnel new handle to the tunnel * @param initiator peer that started the tunnel * @param atsi performance information for the tunnel * @return initial tunnel context for the tunnel * (can be NULL -- that's not an error) */ typedef void *(GNUNET_MESH_InboundTunnelNotificationHandler) (void *cls, struct GNUNET_MESH_Tunnel * tunnel, const struct GNUNET_PeerIdentity * initiator); /** * Function called whenever an inbound tunnel is destroyed. Should clean up * any associated state. This function is NOT called if the client has * explicitly asked for the tunnel to be destroyed using * GNUNET_MESH_tunnel_destroy. It must NOT call GNUNET_MESH_tunnel_destroy on * the tunnel. * * @param cls closure (set from GNUNET_MESH_connect) * @param tunnel connection to the other end (henceforth invalid) * @param tunnel_ctx place where local state associated * with the tunnel is stored */ typedef void (GNUNET_MESH_TunnelEndHandler) (void *cls, const struct GNUNET_MESH_Tunnel * tunnel, void *tunnel_ctx); /** * Connect to the mesh service. * * @param cfg configuration to use * @param cls closure for the various callbacks that follow * (including handlers in the handlers array) * @param new_tunnel function called when an *inbound* tunnel is created * @param cleaner function called when an *inbound* tunnel is destroyed by the * remote peer, it is *not* called if GNUNET_MESH_tunnel_destroy * is called on the tunnel * @param handlers callbacks for messages we care about, NULL-terminated * note that the mesh is allowed to drop notifications about * inbound messages if the client does not process them fast * enough (for this notification type, a bounded queue is used) * @return handle to the mesh service NULL on error * (in this case, init is never called) */ struct GNUNET_MESH_Handle * GNUNET_MESH_connect (const struct GNUNET_CONFIGURATION_Handle *cfg, void *cls, GNUNET_MESH_InboundTunnelNotificationHandler new_tunnel, GNUNET_MESH_TunnelEndHandler cleaner, const struct GNUNET_MESH_MessageHandler *handlers); /** * Disconnect from the mesh service. All tunnels will be destroyed. All tunnel * disconnect callbacks will be called on any still connected peers, notifying * about their disconnection. The registered inbound tunnel cleaner will be * called should any inbound tunnels still exist. * * @param handle connection to mesh to disconnect */ void GNUNET_MESH_disconnect (struct GNUNET_MESH_Handle *handle); /** * Create a new tunnel (we're initiator and will be allowed to add/remove peers * and to broadcast). * * @param h mesh handle * @param tunnel_ctx client's tunnel context to associate with the tunnel * @param peer peer identity the tunnel should go to * @return handle to the tunnel */ struct GNUNET_MESH_Tunnel * GNUNET_MESH_tunnel_create (struct GNUNET_MESH_Handle *h, void *tunnel_ctx, const struct GNUNET_PeerIdentity *peer); /** * Destroy an existing tunnel. The existing callback for the tunnel will NOT * be called. * * @param tunnel tunnel handle */ void GNUNET_MESH_tunnel_destroy (struct GNUNET_MESH_Tunnel *tunnel); /** * Turn on/off the buffering status of the tunnel. * * @param tunnel Tunnel affected. * @param buffer GNUNET_YES to turn buffering on (default), * GNUNET_NO otherwise. */ void GNUNET_MESH_tunnel_buffer (struct GNUNET_MESH_Tunnel *tunnel, int buffer); /** * Handle for a transmission request. */ struct GNUNET_MESH_TransmitHandle; /** * Ask the mesh to call "notify" once it is ready to transmit the * given number of bytes to the specified tunnel. * Only one call can be active at any time, to issue another request, * wait for the callback or cancel the current request. * * @param tunnel tunnel to use for transmission * @param cork is corking allowed for this transmission? * @param maxdelay how long can the message wait? * @param notify_size how many bytes of buffer space does notify want? * @param notify function to call when buffer space is available; * will be called with NULL on timeout or if the overall queue * for this peer is larger than queue_size and this is currently * the message with the lowest priority * @param notify_cls closure for notify * @return non-NULL if the notify callback was queued, * NULL if we can not even queue the request (insufficient * memory); if NULL is returned, "notify" will NOT be called. */ struct GNUNET_MESH_TransmitHandle * GNUNET_MESH_notify_transmit_ready (struct GNUNET_MESH_Tunnel *tunnel, int cork, struct GNUNET_TIME_Relative maxdelay, size_t notify_size, GNUNET_CONNECTION_TransmitReadyNotify notify, void *notify_cls); /** * Cancel the specified transmission-ready notification. * * @param th handle that was returned by "notify_transmit_ready". */ void GNUNET_MESH_notify_transmit_ready_cancel (struct GNUNET_MESH_TransmitHandle *th); /** * Method called to retrieve information about each tunnel the mesh peer * is aware of. * * @param cls Closure. * @param tunnel_number Tunnel number. * @param origin that started the tunnel (owner). * @param target other endpoint of the tunnel */ typedef void (*GNUNET_MESH_TunnelsCB) (void *cls, uint32_t tunnel_number, const struct GNUNET_PeerIdentity *origin, const struct GNUNET_PeerIdentity *target); /** * Method called to retrieve information about a specific tunnel the mesh peer * is aware of, including all transit nodes. * * @param cls Closure. * @param peer Peer in the tunnel's tree. * @param parent Parent of the current peer. All 0 when peer is root. */ typedef void (*GNUNET_MESH_TunnelCB) (void *cls, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_PeerIdentity *parent); /** * Request information about the running mesh peer. * The callback will be called for every tunnel known to the service, * listing all active peers that blong to the tunnel. * * If called again on the same handle, it will overwrite the previous * callback and cls. To retrieve the cls, monitor_cancel must be * called first. * * WARNING: unstable API, likely to change in the future! * * @param h Handle to the mesh peer. * @param callback Function to call with the requested data. * @param callback_cls Closure for @c callback. */ void GNUNET_MESH_get_tunnels (struct GNUNET_MESH_Handle *h, GNUNET_MESH_TunnelsCB callback, void *callback_cls); /** * Request information about a specific tunnel of the running mesh peer. * * WARNING: unstable API, likely to change in the future! * * @param h Handle to the mesh peer. * @param initiator ID of the owner of the tunnel. * @param tunnel_number Tunnel number. * @param callback Function to call with the requested data. * @param callback_cls Closure for @c callback. */ void GNUNET_MESH_show_tunnel (struct GNUNET_MESH_Handle *h, struct GNUNET_PeerIdentity *initiator, uint32_t tunnel_number, GNUNET_MESH_TunnelCB callback, void *callback_cls); /** * Cancel a monitor request. The monitor callback will not be called. * * WARNING: unstable API, likely to change in the future! * * @param h Mesh handle. * * @return Closure given to GNUNET_MESH_monitor, if any. */ void * GNUNET_MESH_get_tunnels_cancel (struct GNUNET_MESH_Handle *h); #if 0 /* keep Emacsens' auto-indent happy */ { #endif #ifdef __cplusplus } #endif /* ifndef GNUNET_MESH_SERVICE_H */ #endif /* end of gnunet_mesh_service.h */