src/include/gnunet_mesh_service.h

   1 /*
   2      This file is part of GNUnet.
   3      (C) 2009, 2010 Christian Grothoff (and other contributing authors)
   4
   5      GNUnet is free software; you can redistribute it and/or modify
   6      it under the terms of the GNU General Public License as published
   7      by the Free Software Foundation; either version 3, or (at your
   8      option) any later version.
   9
  10      GNUnet is distributed in the hope that it will be useful, but
  11      WITHOUT ANY WARRANTY; without even the implied warranty of
  12      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13      General Public License for more details.
  14
  15      You should have received a copy of the GNU General Public License
  16      along with GNUnet; see the file COPYING.  If not, write to the
  17      Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18      Boston, MA 02111-1307, USA.
  19 */
  20
  21 /**
  22  * @file include/gnunet_mesh_service.h
  23  * @brief mesh service; establish tunnels to distant peers
  24  * @author Christian Grothoff
  25  */
  26
  27 #ifndef GNUNET_MESH_SERVICE_H
  28 #define GNUNET_MESH_SERVICE_H
  29
  30 #ifdef __cplusplus
  31 extern "C"
  32 {
  33 #if 0                           /* keep Emacsens' auto-indent happy */
  34 }
  35 #endif
  36 #endif
  37
  38 #include "gnunet_util_lib.h"
  39 #include "gnunet_transport_service.h"
  40
  41 /**
  42  * Version number of GNUnet-mesh API.
  43  */
  44 #define GNUNET_MESH_VERSION 0x00000000
  45
  46
  47 /**
  48  * Opaque handle to the service.
  49  */
  50 struct GNUNET_MESH_Handle;
  51
  52 /**
  53  * Opaque handle to a tunnel.
  54  */
  55 struct GNUNET_MESH_Tunnel;
  56
  57 /**
  58  * Functions with this signature are called whenever a message is
  59  * received or transmitted.
  60  *
  61  * @param cls closure (set from GNUNET_MESH_connect)
  62  * @param tunnel connection to the other end
  63  * @param tunnel_ctx place to store local state associated with the tunnel
  64  * @param sender who sent the message
  65  * @param message the actual message
  66  * @param atsi performance data for the connection
  67  * @return GNUNET_OK to keep the connection open,
  68  *         GNUNET_SYSERR to close it (signal serious error)
  69  */
  70 typedef int (*GNUNET_MESH_MessageCallback) (void *cls,
  71                                             struct GNUNET_MESH_Tunnel * tunnel,
  72                                             void **tunnel_ctx,
  73                                             const struct GNUNET_PeerIdentity *
  74                                             sender,
  75                                             const struct GNUNET_MessageHeader *
  76                                             message,
  77                                             const struct
  78                                             GNUNET_TRANSPORT_ATS_Information *
  79                                             atsi);
  80
  81
  82 /**
  83  * Message handler.  Each struct specifies how to handle on particular
  84  * type of message received.
  85  */
  86 struct GNUNET_MESH_MessageHandler
  87 {
  88   /**
  89    * Function to call for messages of "type".
  90    */
  91   GNUNET_MESH_MessageCallback callback;
  92
  93   /**
  94    * Type of the message this handler covers.
  95    */
  96   uint16_t type;
  97
  98   /**
  99    * Expected size of messages of this type.  Use 0 for variable-size.
 100    * If non-zero, messages of the given type will be discarded if they
 101    * do not have the right size.
 102    */
 103   uint16_t expected_size;
 104
 105 };
 106
 107
 108 /**
 109  * Function called whenever an inbound tunnel is destroyed.  Should clean up
 110  * any associated state.
 111  *
 112  * @param cls closure (set from GNUNET_MESH_connect)
 113  * @param tunnel connection to the other end (henceforth invalid)
 114  * @param tunnel_ctx place where local state associated with the tunnel is stored
 115  */
 116 typedef void (GNUNET_MESH_TunnelEndHandler) (void *cls,
 117                                              const struct GNUNET_MESH_Tunnel *
 118                                              tunnel, void **tunnel_ctx);
 119
 120
 121 /**
 122  * Type for an application.  Values defined in gnunet_applications.h
 123  */
 124 typedef uint32_t GNUNET_MESH_ApplicationType;
 125
 126
 127 /**
 128  * Connect to the mesh service.
 129  *
 130  * @param cfg configuration to use
 131  * @param cls closure for the various callbacks that follow (including handlers in the handlers array)
 132  * @param cleaner function called when an *inbound* tunnel is destroyed
 133  * @param handlers callbacks for messages we care about, NULL-terminated
 134  *                note that the mesh is allowed to drop notifications about inbound
 135  *                messages if the client does not process them fast enough (for this
 136  *                notification type, a bounded queue is used)
 137  * @param stypes Application Types the client claims to offer
 138  * @return handle to the mesh service
 139  *           NULL on error (in this case, init is never called)
 140  */
 141 struct GNUNET_MESH_Handle *GNUNET_MESH_connect (const struct
 142                                                 GNUNET_CONFIGURATION_Handle
 143                                                 *cfg, void *cls,
 144                                                 GNUNET_MESH_TunnelEndHandler
 145                                                 cleaner,
 146                                                 const struct
 147                                                 GNUNET_MESH_MessageHandler
 148                                                 *handlers,
 149                                                 const
 150                                                 GNUNET_MESH_ApplicationType
 151                                                 *stypes);
 152
 153 /**
 154  * Get the peer on the other side of this tunnel if it is just one. Return NULL otherwise
 155  *
 156  * @param tunnel the tunnel
 157  * @return the peer or NULL
 158  */
 159 const struct GNUNET_PeerIdentity *GNUNET_MESH_get_peer (const struct
 160                                                         GNUNET_MESH_Tunnel
 161                                                         *tunnel);
 162
 163
 164 /**
 165  * Disconnect from the mesh service.
 166  *
 167  * @param handle connection to mesh to disconnect
 168  */
 169 void GNUNET_MESH_disconnect (struct GNUNET_MESH_Handle *handle);
 170
 171
 172
 173
 174
 175 /**
 176  * Method called whenever a tunnel falls apart.
 177  *
 178  * @param cls closure
 179  * @param peer peer identity the tunnel stopped working with
 180  */
 181 typedef void (*GNUNET_MESH_TunnelDisconnectHandler) (void *cls,
 182                                                      const struct
 183                                                      GNUNET_PeerIdentity *
 184                                                      peer);
 185
 186
 187 /**
 188  * Method called whenever a tunnel is established.
 189  *
 190  * @param cls closure
 191  * @param peer peer identity the tunnel was created to, NULL on timeout
 192  * @param atsi performance data for the connection
 193  */
 194 typedef void (*GNUNET_MESH_TunnelConnectHandler) (void *cls,
 195                                                   const struct
 196                                                   GNUNET_PeerIdentity * peer,
 197                                                   const struct
 198                                                   GNUNET_TRANSPORT_ATS_Information
 199                                                   * atsi);
 200
 201
 202
 203 /**
 204  * Handle for a request to the mesh to connect or disconnect
 205  * from a particular peer.  Can be used to cancel the request
 206  * (before the 'cont'inuation is called).
 207  */
 208 struct GNUNET_MESH_PeerRequestHandle;
 209
 210
 211 /**
 212  * Request that the mesh should try to connect to any of the given peers.
 213  *
 214  * @param h mesh handle
 215  * @param timeout how long to try to establish a connection
 216  * @param num_peers length of the peers array
 217  * @param peers list of candidates to connect to
 218  * @param connect_handler function to call on successful connect (or timeout)
 219  * @param disconnect_handler function to call on disconnect
 220  * @param handler_cls closure for handler
 221  * @return NULL on error (handler will not be called), otherwise handle for cancellation
 222  */
 223 struct GNUNET_MESH_Tunnel *GNUNET_MESH_peer_request_connect_any (struct
 224                                                                  GNUNET_MESH_Handle
 225                                                                  *h,
 226                                                                  struct
 227                                                                  GNUNET_TIME_Relative
 228                                                                  timeout,
 229                                                                  unsigned int
 230                                                                  num_peers,
 231                                                                  const struct
 232                                                                  GNUNET_PeerIdentity
 233                                                                  *peers,
 234                                                                  GNUNET_MESH_TunnelConnectHandler
 235                                                                  connect_handler,
 236                                                                  GNUNET_MESH_TunnelDisconnectHandler
 237                                                                  disconnect_handler,
 238                                                                  void
 239                                                                  *handler_cls);
 240
 241
 242 /**
 243  * Request that the mesh should try to connect to all of the given peers.
 244  * Messages send to the tunnel will be broadcast.
 245  *
 246  * @param h mesh handle
 247  * @param timeout how long to try to establish a connection
 248  * @param num_peers length of the peers array
 249  * @param peers list of candidates to connect to
 250  * @param connect_handler function to call on successful connect (or timeout);
 251  *                will be called for EACH of the peers in the list and
 252  *                once at the end with 'NULL' on timeout or once we've connected
 253  *                to each of the peers in the list
 254  * @param disconnect_handler function called if a peer drops out of the tunnel;
 255  *                the mesh will NOT try to add it back automatically
 256  * @param handler_cls closure for handler
 257  * @return NULL on error (handler will not be called), otherwise handle for cancellation
 258  */
 259 struct GNUNET_MESH_Tunnel *GNUNET_MESH_peer_request_connect_all (struct
 260                                                                  GNUNET_MESH_Handle
 261                                                                  *h,
 262                                                                  struct
 263                                                                  GNUNET_TIME_Relative
 264                                                                  timeout,
 265                                                                  unsigned int
 266                                                                  num_peers,
 267                                                                  const struct
 268                                                                  GNUNET_PeerIdentity
 269                                                                  *peers,
 270                                                                  GNUNET_MESH_TunnelConnectHandler
 271                                                                  connect_handler,
 272                                                                  GNUNET_MESH_TunnelDisconnectHandler
 273                                                                  disconnect_handler,
 274                                                                  void
 275                                                                  *handler_cls);
 276
 277
 278 /**
 279  * Request that a peer should be added to the tunnel.  The existing
 280  * connect handler will be called ONCE with either success or failure.
 281  *
 282  * @param tunnel handle to existing tunnel
 283  * @param timeout how long to try to establish a connection
 284  * @param peer peer to add
 285  */
 286 void GNUNET_MESH_peer_request_connect_add (struct GNUNET_MESH_Tunnel *tunnel,
 287                                            struct GNUNET_TIME_Relative timeout,
 288                                            const struct GNUNET_PeerIdentity
 289                                            *peer);
 290
 291
 292 /**
 293  * Request that a peer should be removed from the tunnel.  The existing
 294  * disconnect handler will be called ONCE if we were connected.
 295  *
 296  * @param tunnel handle to existing tunnel
 297  * @param peer peer to remove
 298  */
 299 void GNUNET_MESH_peer_request_connect_del (struct GNUNET_MESH_Tunnel *tunnel,
 300                                            const struct GNUNET_PeerIdentity
 301                                            *peer);
 302
 303
 304 /**
 305  * Request that the mesh should try to connect to a peer supporting the given
 306  * message type.
 307  *
 308  * @param h mesh handle
 309  * @param timeout how long to try to establish a connection
 310  * @param app_type application type that must be supported by the peer (MESH should
 311  *                discover peer in proximity handling this type)
 312  * @param connect_handler function to call on successful connect (or timeout);
 313  *                will be called for EACH of the peers in the list and
 314  *                once at the end with 'NULL' on timeout or once we've connected
 315  *                to each of the peers in the list
 316  * @param disconnect_handler function called if a peer drops out of the tunnel;
 317  *                the mesh will NOT try to add it back automatically
 318  * @param handler_cls closure for handler
 319  * @return NULL on error (handler will not be called), otherwise handle for cancellation
 320  */
 321 struct GNUNET_MESH_Tunnel *GNUNET_MESH_peer_request_connect_by_type (struct
 322                                                                      GNUNET_MESH_Handle
 323                                                                      *h,
 324                                                                      struct
 325                                                                      GNUNET_TIME_Relative
 326                                                                      timeout,
 327                                                                      GNUNET_MESH_ApplicationType
 328                                                                      app_type,
 329                                                                      GNUNET_MESH_TunnelConnectHandler
 330                                                                      connect_handler,
 331                                                                      GNUNET_MESH_TunnelDisconnectHandler
 332                                                                      disconnect_handler,
 333                                                                      void
 334                                                                      *handler_cls);
 335
 336
 337 /**
 338  * Cancel a pending request to connect to a particular peer.  Destroys the
 339  * tunnel.
 340  *
 341  * @param req request handle that was returned for the original request
 342  */
 343 void GNUNET_MESH_peer_request_connect_cancel (struct GNUNET_MESH_Tunnel *req);
 344
 345
 346 /**
 347  * Handle for a transmission request.
 348  */
 349 struct GNUNET_MESH_TransmitHandle;
 350
 351
 352 /**
 353  * Ask the mesh to call "notify" once it is ready to transmit the
 354  * given number of bytes to the specified "target".  If we are not yet
 355  * connected to the specified peer, a call to this function will cause
 356  * us to try to establish a connection.
 357  *
 358  * @param tunnel tunnel to use for transmission
 359  * @param cork is corking allowed for this transmission?
 360  * @param priority how important is the message?
 361  * @param maxdelay how long can the message wait?
 362  * @param target destination for the message, NULL for multicast to all tunnel targets
 363  * @param notify_size how many bytes of buffer space does notify want?
 364  * @param notify function to call when buffer space is available;
 365  *        will be called with NULL on timeout or if the overall queue
 366  *        for this peer is larger than queue_size and this is currently
 367  *        the message with the lowest priority
 368  * @param notify_cls closure for notify
 369  * @return non-NULL if the notify callback was queued,
 370  *         NULL if we can not even queue the request (insufficient
 371  *         memory); if NULL is returned, "notify" will NOT be called.
 372  */
 373 struct GNUNET_MESH_TransmitHandle *GNUNET_MESH_notify_transmit_ready (struct
 374                                                                       GNUNET_MESH_Tunnel
 375                                                                       *tunnel,
 376                                                                       int cork,
 377                                                                       uint32_t
 378                                                                       priority,
 379                                                                       struct
 380                                                                       GNUNET_TIME_Relative
 381                                                                       maxdelay,
 382                                                                       const
 383                                                                       struct
 384                                                                       GNUNET_PeerIdentity
 385                                                                       *target,
 386                                                                       size_t
 387                                                                       notify_size,
 388                                                                       GNUNET_CONNECTION_TransmitReadyNotify
 389                                                                       notify,
 390                                                                       void
 391                                                                       *notify_cls);
 392
 393
 394 /**
 395  * Cancel the specified transmission-ready notification.
 396  *
 397  * @param th handle that was returned by "notify_transmit_ready".
 398  */
 399 void GNUNET_MESH_notify_transmit_ready_cancel (struct GNUNET_MESH_TransmitHandle
 400                                                *th);
 401
 402 void GNUNET_MESH_tunnel_set_head (struct GNUNET_MESH_Tunnel *tunnel,
 403                                   void *head);
 404 void GNUNET_MESH_tunnel_set_tail (struct GNUNET_MESH_Tunnel *tunnel,
 405                                   void *tail);
 406 void *GNUNET_MESH_tunnel_get_head (struct GNUNET_MESH_Tunnel *tunnel);
 407 void *GNUNET_MESH_tunnel_get_tail (struct GNUNET_MESH_Tunnel *tunnel);
 408
 409 void GNUNET_MESH_tunnel_set_data (struct GNUNET_MESH_Tunnel *tunnel,
 410                                   void *data);
 411 void *GNUNET_MESH_tunnel_get_data (struct GNUNET_MESH_Tunnel *tunnel);
 412
 413 #if 0                           /* keep Emacsens' auto-indent happy */
 414 {
 415 #endif
 416 #ifdef __cplusplus
 417 }
 418 #endif
 419
 420 /* ifndef GNUNET_MESH_SERVICE_H */
 421 #endif
 422 /* end of gnunet_mesh_service.h */