- move include file

1 files changed, 619 insertions, 0 deletions

diff --git a/src/include/gnunet_cadet_service.h b/src/include/gnunet_cadet_service.h
new file mode 100644
index 000000000..e69c9eaa7
--- /dev/null
+++ b/src/include/gnunet_cadet_service.h
@@ -0,0 +1,619 @@
+/*
+     This file is part of GNUnet.
+     (C) 2009 - 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_cadet_service.h
+ * @brief cadet service; establish channels to distant peers
+ * @author Christian Grothoff
+ */
+
+#ifndef GNUNET_CADET_SERVICE_H
+#define GNUNET_CADET_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-cadet API.
+ */
+#define GNUNET_CADET_VERSION 0x00000003
+
+
+/**
+ * Opaque handle to the service.
+ */
+struct GNUNET_CADET_Handle;
+
+/**
+ * Opaque handle to a channel.
+ */
+struct GNUNET_CADET_Channel;
+
+/**
+ * Hash to be used in Cadet communication. Only 256 bits needed,
+ * instead of the 512 from @c GNUNET_HashCode.
+ *
+ */
+struct GNUNET_CADET_Hash
+{
+  unsigned char bits[256 / 8];
+};
+
+/**
+ * Channel options.
+ * Second line indicates filed in the CadetChannelInfo union carrying the answer.
+ */
+enum GNUNET_CADET_ChannelOption
+{
+  /**
+   * Default options: unreliable, default buffering, not out of order.
+   */
+  GNUNET_CADET_OPTION_DEFAULT    = 0x0,
+
+  /**
+   * Disable buffering on intermediate nodes (for minimum latency).
+   * Yes/No.
+   */
+  GNUNET_CADET_OPTION_NOBUFFER   = 0x1,
+
+  /**
+   * Enable channel reliability, lost messages will be retransmitted.
+   * Yes/No.
+   */
+  GNUNET_CADET_OPTION_RELIABLE   = 0x2,
+
+  /**
+   * Enable out of order delivery of messages.
+   * Yes/No.
+   */
+  GNUNET_CADET_OPTION_OOORDER    = 0x4,
+
+  /**
+   * Who is the peer at the other end of the channel.
+   * Only for use in @c GNUNET_CADET_channel_get_info
+   * struct GNUNET_PeerIdentity *peer
+   */
+  GNUNET_CADET_OPTION_PEER       = 0x8
+
+};
+
+
+/**
+ * Functions with this signature are called whenever a message is
+ * received.
+ *
+ * Each time the function must call #GNUNET_CADET_receive_done on the channel
+ * in order to receive the next message. This doesn't need to be immediate:
+ * can be delayed if some processing is done on the message.
+ *
+ * @param cls Closure (set from #GNUNET_CADET_connect).
+ * @param channel Connection to the other end.
+ * @param channel_ctx Place to store local state associated with the channel.
+ * @param message The actual message.
+ * @return #GNUNET_OK to keep the channel open,
+ *         #GNUNET_SYSERR to close it (signal serious error).
+ */
+typedef int (*GNUNET_CADET_MessageCallback) (void *cls,
+                                            struct GNUNET_CADET_Channel *channel,
+                                            void **channel_ctx,
+                                            const struct GNUNET_MessageHeader *message);
+
+
+/**
+ * Message handler.  Each struct specifies how to handle on particular
+ * type of message received.
+ */
+struct GNUNET_CADET_MessageHandler
+{
+  /**
+   * Function to call for messages of "type".
+   */
+  GNUNET_CADET_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 channel
+ * the other peer initiated.
+ * Only called (once) upon reception of data with a message type which was
+ * subscribed to in #GNUNET_CADET_connect.
+ *
+ * A call to #GNUNET_CADET_channel_destroy causes te channel to be ignored. In
+ * this case the handler MUST return NULL.
+ *
+ * @param cls closure
+ * @param channel new handle to the channel
+ * @param initiator peer that started the channel
+ * @param port Port this channel is for.
+ * @param options CadetOption flag field, with all active option bits set to 1.
+ *
+ * @return initial channel context for the channel
+ *         (can be NULL -- that's not an error)
+ */
+typedef void *(GNUNET_CADET_InboundChannelNotificationHandler) (void *cls,
+                                                               struct
+                                                               GNUNET_CADET_Channel
+                                                               * channel,
+                                                               const struct
+                                                               GNUNET_PeerIdentity
+                                                               * initiator,
+                                                               uint32_t port,
+                                                               enum GNUNET_CADET_ChannelOption
+                                                               options);
+
+
+/**
+ * Function called whenever a channel is destroyed.  Should clean up
+ * any associated state.
+ *
+ * It must NOT call #GNUNET_CADET_channel_destroy on the channel.
+ *
+ * @param cls closure (set from #GNUNET_CADET_connect)
+ * @param channel connection to the other end (henceforth invalid)
+ * @param channel_ctx place where local state associated
+ *                   with the channel is stored
+ */
+typedef void (GNUNET_CADET_ChannelEndHandler) (void *cls,
+                                              const struct GNUNET_CADET_Channel *
+                                              channel,
+                                              void *channel_ctx);
+
+
+/**
+ * Connect to the cadet service.
+ *
+ * @param cfg Configuration to use.
+ * @param cls Closure for the various callbacks that follow (including
+ *            handlers in the handlers array).
+ * @param new_channel Function called when an *incoming* channel is created.
+ *                    Can be NULL if no inbound channels are desired.
+ *                    See @a ports.
+ * @param cleaner Function called when a channel is destroyed by the remote peer.
+ *                It is NOT called if #GNUNET_CADET_channel_destroy is called on
+ *                the channel.
+ * @param handlers Callbacks for messages we care about, NULL-terminated. Each
+ *                 one must call #GNUNET_CADET_receive_done on the channel to
+ *                 receive the next message.  Messages of a type that is not
+ *                 in the handlers array are ignored if received.
+ * @param ports NULL or 0-terminated array of port numbers for incoming channels.
+ *              See @a new_channel.
+ *
+ * @return handle to the cadet service NULL on error
+ *         (in this case, init is never called)
+ */
+struct GNUNET_CADET_Handle *
+GNUNET_CADET_connect (const struct GNUNET_CONFIGURATION_Handle *cfg, void *cls,
+                     GNUNET_CADET_InboundChannelNotificationHandler new_channel,
+                     GNUNET_CADET_ChannelEndHandler cleaner,
+                     const struct GNUNET_CADET_MessageHandler *handlers,
+                     const uint32_t *ports);
+
+
+/**
+ * Disconnect from the cadet service. All channels will be destroyed. All channel
+ * disconnect callbacks will be called on any still connected peers, notifying
+ * about their disconnection. The registered inbound channel cleaner will be
+ * called should any inbound channels still exist.
+ *
+ * @param handle connection to cadet to disconnect
+ */
+void
+GNUNET_CADET_disconnect (struct GNUNET_CADET_Handle *handle);
+
+
+/**
+ * Create a new channel towards a remote peer.
+ *
+ * If the destination port is not open by any peer or the destination peer
+ * does not accept the channel, #GNUNET_CADET_ChannelEndHandler will be called
+ * for this channel.
+ *
+ * @param h cadet handle
+ * @param channel_ctx client's channel context to associate with the channel
+ * @param peer peer identity the channel should go to
+ * @param port Port number.
+ * @param options CadetOption flag field, with all desired option bits set to 1.
+ *
+ * @return handle to the channel
+ */
+struct GNUNET_CADET_Channel *
+GNUNET_CADET_channel_create (struct GNUNET_CADET_Handle *h,
+                            void *channel_ctx,
+                            const struct GNUNET_PeerIdentity *peer,
+                            uint32_t port,
+                            enum GNUNET_CADET_ChannelOption options);
+
+
+/**
+ * Destroy an existing channel.
+ *
+ * The existing end callback for the channel will be called immediately.
+ * Any pending outgoing messages will be sent but no incoming messages will be
+ * accepted and no data callbacks will be called.
+ *
+ * @param channel Channel handle, becomes invalid after this call.
+ */
+void
+GNUNET_CADET_channel_destroy (struct GNUNET_CADET_Channel *channel);
+
+
+/**
+ * Struct to retrieve info about a channel.
+ */
+union GNUNET_CADET_ChannelInfo
+{
+
+  /**
+   * #GNUNET_YES / #GNUNET_NO, for binary flags.
+   */
+  int yes_no;
+
+  /**
+   * Peer on the other side of the channel
+   */
+  const struct GNUNET_PeerIdentity peer;
+};
+
+
+/**
+ * Get information about a channel.
+ *
+ * @param channel Channel handle.
+ * @param option Query type GNUNET_CADET_OPTION_*
+ * @param ... dependant on option, currently not used
+ * @return Union with an answer to the query.
+ */
+const union GNUNET_CADET_ChannelInfo *
+GNUNET_CADET_channel_get_info (struct GNUNET_CADET_Channel *channel,
+                              enum GNUNET_CADET_ChannelOption option, ...);
+
+
+/**
+ * Handle for a transmission request.
+ */
+struct GNUNET_CADET_TransmitHandle;
+
+
+/**
+ * Ask the cadet to call @a notify once it is ready to transmit the
+ * given number of bytes to the specified channel.
+ * Only one call can be active at any time, to issue another request,
+ * wait for the callback or cancel the current request.
+ *
+ * @param channel channel 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 @a 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, @a notify will NOT be called.
+ */
+struct GNUNET_CADET_TransmitHandle *
+GNUNET_CADET_notify_transmit_ready (struct GNUNET_CADET_Channel *channel,
+                                   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_CADET_notify_transmit_ready_cancel (struct GNUNET_CADET_TransmitHandle
+                                          *th);
+
+
+/**
+ * Indicate readiness to receive the next message on a channel.
+ *
+ * Should only be called once per handler called.
+ *
+ * @param channel Channel that will be allowed to call another handler.
+ */
+void
+GNUNET_CADET_receive_done (struct GNUNET_CADET_Channel *channel);
+
+
+
+/******************************************************************************/
+/********************       MONITORING /DEBUG API     *************************/
+/******************************************************************************/
+/* The following calls are not useful for normal CADET operation, but for      */
+/* debug and monitoring of the cadet state. They can be safely ignored.        */
+/* The API can change at any point without notice.                            */
+/* Please contact the developer if you consider any of this calls useful for  */
+/* normal cadet applications.                                                  */
+/******************************************************************************/
+
+
+/**
+ * Method called to retrieve information about a specific channel the cadet peer
+ * is aware of, including all transit nodes.
+ *
+ * @param cls Closure.
+ * @param root Root of the channel.
+ * @param dest Destination of the channel.
+ * @param port Destination port of the channel.
+ * @param root_channel_number Local number for root, if known.
+ * @param dest_channel_number Local number for dest, if known.
+ * @param public_channel_numbe Number for P2P, always known.
+ */
+typedef void (*GNUNET_CADET_ChannelCB) (void *cls,
+                                       const struct GNUNET_PeerIdentity *root,
+                                       const struct GNUNET_PeerIdentity *dest,
+                                       uint32_t port,
+                                       uint32_t root_channel_number,
+                                       uint32_t dest_channel_number,
+                                       uint32_t public_channel_number);
+
+/**
+ * Method called to retrieve information about all peers in CADET, called
+ * once per peer.
+ *
+ * After last peer has been reported, an additional call with NULL is done.
+ *
+ * @param cls Closure.
+ * @param peer Peer, or NULL on "EOF".
+ * @param tunnel Do we have a tunnel towards this peer?
+ * @param n_paths Number of known paths towards this peer.
+ * @param best_path How long is the best path?
+ *                  (0 = unknown, 1 = ourselves, 2 = neighbor)
+ */
+typedef void (*GNUNET_CADET_PeersCB) (void *cls,
+                                     const struct GNUNET_PeerIdentity *peer,
+                                     int tunnel, unsigned int n_paths,
+                                     unsigned int best_path);
+
+/**
+ * Method called to retrieve information about a specific peer
+ * known to the service.
+ *
+ * @param cls Closure.
+ * @param peer Peer ID.
+ * @param tunnel Do we have a tunnel towards this peer? #GNUNET_YES/#GNUNET_NO
+ * @param neighbor Is this a direct neighbor? #GNUNET_YES/#GNUNET_NO
+ * @param n_paths Number of paths known towards peer.
+ * @param paths Array of PEER_IDs representing all paths to reach the peer.
+ *              Each path starts with the local peer.
+ *              Each path ends with the destination peer (given in @c peer).
+ */
+typedef void (*GNUNET_CADET_PeerCB) (void *cls,
+                                    const struct GNUNET_PeerIdentity *peer,
+                                    int tunnel,
+                                    int neighbor,
+                                    unsigned int n_paths,
+                                    struct GNUNET_PeerIdentity *paths);
+
+
+/**
+ * Method called to retrieve information about all tunnels in CADET, called
+ * once per tunnel.
+ *
+ * After last tunnel has been reported, an additional call with NULL is done.
+ *
+ * @param cls Closure.
+ * @param peer Destination peer, or NULL on "EOF".
+ * @param channels Number of channels.
+ * @param connections Number of connections.
+ * @param estate Encryption state.
+ * @param cstate Connectivity state.
+ */
+typedef void (*GNUNET_CADET_TunnelsCB) (void *cls,
+                                       const struct GNUNET_PeerIdentity *peer,
+                                       unsigned int channels,
+                                       unsigned int connections,
+                                       uint16_t estate,
+                                       uint16_t cstate);
+
+
+
+/**
+ * Method called to retrieve information about a specific tunnel the cadet peer
+ * has established, o`r is trying to establish.
+ *
+ * @param cls Closure.
+ * @param peer Peer towards whom the tunnel is directed.
+ * @param n_channels Number of channels.
+ * @param n_connections Number of connections.
+ * @param channels Channels.
+ * @param connections Connections.
+ * @param estate Encryption state.
+ * @param cstate Connectivity state.
+ */
+typedef void (*GNUNET_CADET_TunnelCB) (void *cls,
+                                      const struct GNUNET_PeerIdentity *peer,
+                                      unsigned int n_channels,
+                                      unsigned int n_connections,
+                                      uint32_t *channels,
+                                      struct GNUNET_CADET_Hash *connections,
+                                      unsigned int estate,
+                                      unsigned int cstate);
+
+/**
+ * Request information about a specific channel of the running cadet peer.
+ *
+ * WARNING: unstable API, likely to change in the future!
+ *
+ * @param h Handle to the cadet peer.
+ * @param peer ID of the other end of the channel.
+ * @param channel_number Channel number.
+ * @param callback Function to call with the requested data.
+ * @param callback_cls Closure for @c callback.
+ */
+void
+GNUNET_CADET_get_channel (struct GNUNET_CADET_Handle *h,
+                         struct GNUNET_PeerIdentity *peer,
+                         uint32_t channel_number,
+                         GNUNET_CADET_ChannelCB callback,
+                         void *callback_cls);
+
+
+/**
+ * Request information about peers known to the running cadet service.
+ * The callback will be called for every peer known to the service.
+ * Only one info request (of any kind) can be active at once.
+ *
+ *
+ * WARNING: unstable API, likely to change in the future!
+ *
+ * @param h Handle to the cadet peer.
+ * @param callback Function to call with the requested data.
+ * @param callback_cls Closure for @c callback.
+ *
+ * @return #GNUNET_OK / #GNUNET_SYSERR
+ */
+int
+GNUNET_CADET_get_peers (struct GNUNET_CADET_Handle *h,
+                       GNUNET_CADET_PeersCB callback,
+                       void *callback_cls);
+
+/**
+ * Cancel a peer info request. The callback will not be called (anymore).
+ *
+ * WARNING: unstable API, likely to change in the future!
+ *
+ * @param h Cadet handle.
+ *
+ * @return Closure given to GNUNET_CADET_get_peers.
+ */
+void *
+GNUNET_CADET_get_peers_cancel (struct GNUNET_CADET_Handle *h);
+
+
+/**
+ * Request information about a peer known to the running cadet peer.
+ * The callback will be called for the tunnel once.
+ * Only one info request (of any kind) can be active at once.
+ *
+ * WARNING: unstable API, likely to change in the future!
+ *
+ * @param h Handle to the cadet peer.
+ * @param id Peer whose tunnel to examine.
+ * @param callback Function to call with the requested data.
+ * @param callback_cls Closure for @c callback.
+ *
+ * @return #GNUNET_OK / #GNUNET_SYSERR
+ */
+int
+GNUNET_CADET_get_peer (struct GNUNET_CADET_Handle *h,
+                      const struct GNUNET_PeerIdentity *id,
+                      GNUNET_CADET_PeerCB callback,
+                      void *callback_cls);
+
+/**
+ * Request information about tunnels of the running cadet peer.
+ * The callback will be called for every tunnel of the service.
+ * Only one info request (of any kind) can be active at once.
+ *
+ * WARNING: unstable API, likely to change in the future!
+ *
+ * @param h Handle to the cadet peer.
+ * @param callback Function to call with the requested data.
+ * @param callback_cls Closure for @c callback.
+ *
+ * @return #GNUNET_OK / #GNUNET_SYSERR
+ */
+int
+GNUNET_CADET_get_tunnels (struct GNUNET_CADET_Handle *h,
+                         GNUNET_CADET_TunnelsCB callback,
+                         void *callback_cls);
+
+/**
+ * Cancel a monitor request. The monitor callback will not be called.
+ *
+ * @param h Cadet handle.
+ *
+ * @return Closure given to GNUNET_CADET_monitor, if any.
+ */
+void *
+GNUNET_CADET_get_tunnels_cancel (struct GNUNET_CADET_Handle *h);
+
+
+/**
+ * Request information about a tunnel of the running cadet peer.
+ * The callback will be called for the tunnel once.
+ * Only one info request (of any kind) can be active at once.
+ *
+ * WARNING: unstable API, likely to change in the future!
+ *
+ * @param h Handle to the cadet peer.
+ * @param id Peer whose tunnel to examine.
+ * @param callback Function to call with the requested data.
+ * @param callback_cls Closure for @c callback.
+ *
+ * @return #GNUNET_OK / #GNUNET_SYSERR
+ */
+int
+GNUNET_CADET_get_tunnel (struct GNUNET_CADET_Handle *h,
+                        const struct GNUNET_PeerIdentity *id,
+                        GNUNET_CADET_TunnelCB callback,
+                        void *callback_cls);
+
+/**
+ * Create a message queue for a cadet channel.
+ * The message queue can only be used to transmit messages,
+ * not to receive them.
+ *
+ * @param channel the channel to create the message qeue for
+ * @return a message queue to messages over the channel
+ */
+struct GNUNET_MQ_Handle *
+GNUNET_CADET_mq_create (struct GNUNET_CADET_Channel *channel);
+
+
+#if 0                           /* keep Emacsens' auto-indent happy */
+{
+#endif
+#ifdef __cplusplus
+}
+#endif
+
+/* ifndef GNUNET_CADET_SERVICE_H */
+#endif
+/* end of gnunet_cadet_service.h */