2 This file is part of GNUnet
3 (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Christian Grothoff (and other contributing authors)
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 2, or (at your
8 option) any later version.
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.
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.
22 * @file dv/plugin_transport_dv.c
23 * @brief DV transport service, takes incoming DV requests and deals with
25 * @author Christian Grothoff
31 * As a start, the dv plugin needs to listen for information from the dv
32 * service. The plugin (?) will be notified by core (?) when a tcp/udp/whatever
33 * message comes in that should be for dv. The plugin will then hand off the message
34 * to the dv service which will decrypt/validate the message (?) and then send the
35 * result back to us (the transport) which will then send the message to the transport
38 * Or, core will notify the dv service directly which will validate,
39 * etc. and then just send a message to us.
41 * For starters, this plugin needs to have a client which will listen for messages from
42 * the dv service that need to be sent up to the gnunet-transport-service.
44 * Messages sent from the dv transport get passed to the dv service which deals
45 * with the actual sending (how much state does this transport need? should it know
46 * which peers it is currently connected to and their distances, or just assume that
47 * anything should be passed along to the dv service?).
50 #include "gnunet_protocols.h"
51 #include "gnunet_connection_lib.h"
52 #include "gnunet_server_lib.h"
53 #include "gnunet_service_lib.h"
54 #include "gnunet_statistics_service.h"
55 #include "gnunet_dv_service.h"
56 #include "gnunet_transport_service.h"
57 #include "../transport/plugin_transport.h"
60 #define DEBUG_TEMPLATE GNUNET_NO
63 * Encapsulation of all of the state of the plugin.
69 * Session handle for connections.
75 * Stored in a linked list.
80 * Pointer to the global plugin struct.
82 struct Plugin *plugin;
85 * The client (used to identify this connection)
90 * Continuation function to call once the transmission buffer
91 * has again space available. NULL if there is no
92 * continuation to call.
94 GNUNET_TRANSPORT_TransmitContinuation transmit_cont;
97 * Closure for transmit_cont.
99 void *transmit_cont_cls;
102 * To whom are we talking to (set to our identity
103 * if we are still waiting for the welcome message)
105 struct GNUNET_PeerIdentity sender;
108 * At what time did we reset last_received last?
110 struct GNUNET_TIME_Absolute last_quota_update;
113 * How many bytes have we received since the "last_quota_update"
116 uint64_t last_received;
119 * Number of bytes per ms that this peer is allowed
127 * Encapsulation of all of the state of the plugin.
134 struct GNUNET_TRANSPORT_PluginEnvironment *env;
137 * List of open sessions.
139 struct Session *sessions;
144 //struct GNUNET_SERVER_Handle *server;
147 * Handle to the running service.
149 //struct GNUNET_SERVICE_Context *service;
152 * Copy of the handler array where the closures are
153 * set to this struct's instance.
155 struct GNUNET_SERVER_MessageHandler *handlers;
158 * Handle to the DV service
160 struct GNUNET_DV_Handle *dv_handle;
165 * Handler for messages received from the DV service.
167 void handle_dv_message_received (void *cls,
168 struct GNUNET_PeerIdentity *sender,
172 char *sender_address,
173 size_t sender_address_len)
175 struct Plugin *plugin = cls;
177 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
178 "plugin_transport_dv",
179 _("PLUGIN Received message from %s of type %d, distance %u!\n"),
180 "DV SERVICE", ntohs(((struct GNUNET_MessageHeader *)msg)->type), distance);
182 plugin->env->receive(plugin->env->cls,
184 (struct GNUNET_MessageHeader *)msg,
186 NULL, /* FIXME: pass session! */
193 /* Question: how does the transport service learn of a newly connected (gossipped about)
194 * DV peer? Should the plugin (here) create a HELLO for that peer and send it along,
195 * or should the DV service create a HELLO and send it to us via the other part?
199 * Function that can be used by the transport service to transmit
200 * a message using the plugin.
203 * @param target who should receive this message
204 * @param priority how important is the message
205 * @param msgbuf the message to transmit
206 * @param msgbuf_size number of bytes in 'msgbuf'
207 * @param timeout when should we time out
208 * @param session the session used
209 * @param addr the address to use (can be NULL if the plugin
210 * is "on its own" (i.e. re-use existing TCP connection))
211 * @param addrlen length of the address in bytes
212 * @param force_address GNUNET_YES if the plugin MUST use the given address,
213 * otherwise the plugin may use other addresses or
214 * existing connections (if available)
215 * @param cont continuation to call once the message has
216 * been transmitted (or if the transport is ready
217 * for the next transmission call; or if the
218 * peer disconnected...)
219 * @param cont_cls closure for cont
220 * @return number of bytes used (on the physical network, with overheads);
221 * -1 on hard errors (i.e. address invalid); 0 is a legal value
222 * and does NOT mean that the message was not transmitted (DV)
225 dv_plugin_send (void *cls,
226 const struct GNUNET_PeerIdentity *target,
229 unsigned int priority,
230 struct GNUNET_TIME_Relative timeout,
231 struct Session *session,
235 GNUNET_TRANSPORT_TransmitContinuation
236 cont, void *cont_cls)
239 struct Plugin *plugin = cls;
242 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "DV API: Received send request from transport, calling GNUNET_DV_send\n");
244 ret = GNUNET_DV_send(plugin->dv_handle,
261 * Function that can be used to force the plugin to disconnect
262 * from the given peer and cancel all previous transmissions
263 * (and their continuations).
266 * @param target peer from which to disconnect
269 dv_plugin_disconnect (void *cls,
270 const struct GNUNET_PeerIdentity *target)
272 // struct Plugin *plugin = cls;
273 // TODO: Add message type to send to dv service to "disconnect" a peer
278 * Convert the transports address to a nice, human-readable
282 * @param type name of the transport that generated the address
283 * @param addr one of the addresses of the host, NULL for the last address
284 * the specific address format depends on the transport
285 * @param addrlen length of the address
286 * @param numeric should (IP) addresses be displayed in numeric form?
287 * @param timeout after how long should we give up?
288 * @param asc function to call on each string
289 * @param asc_cls closure for asc
292 dv_plugin_address_pretty_printer (void *cls,
297 struct GNUNET_TIME_Relative timeout,
298 GNUNET_TRANSPORT_AddressStringCallback
305 * Convert the DV address to a pretty string.
308 * @param addr the (hopefully) DV address
309 * @param addrlen the length of the address
311 * @return string representing the DV address
313 static const char *address_to_string (void *cls,
317 static char return_buffer[2 * 4 + 2]; // Two four character peer identity prefixes a ':' and '\0'
319 struct GNUNET_CRYPTO_HashAsciiEncoded peer_hash;
320 struct GNUNET_CRYPTO_HashAsciiEncoded via_hash;
321 struct GNUNET_PeerIdentity *peer;
322 struct GNUNET_PeerIdentity *via;
323 char *addr_buf = (char *)addr;
325 if (addrlen == (2 * sizeof(struct GNUNET_PeerIdentity)))
327 peer = (struct GNUNET_PeerIdentity *)addr_buf;
328 via = (struct GNUNET_PeerIdentity *)&addr_buf[sizeof(struct GNUNET_PeerIdentity)];
330 GNUNET_CRYPTO_hash_to_enc (&peer->hashPubKey, &peer_hash);
331 peer_hash.encoding[4] = '\0';
332 GNUNET_CRYPTO_hash_to_enc (&via->hashPubKey, &via_hash);
333 via_hash.encoding[4] = '\0';
334 GNUNET_snprintf (return_buffer,
335 sizeof (return_buffer),
343 return return_buffer;
347 * Another peer has suggested an address for this
348 * peer and transport plugin. Check that this could be a valid
349 * address. If so, consider adding it to the list
353 * @param addr pointer to the address
354 * @param addrlen length of addr
355 * @return GNUNET_OK if this is a plausible address for this peer
358 * FIXME: does this mean anything for the DV plugin?
361 dv_plugin_address_suggested (void *cls,
362 void *addr, size_t addrlen)
364 /* struct Plugin *plugin = cls; */
366 /* check if the address is plausible; if so,
367 add it to our list! */
373 * Entry point for the plugin.
376 libgnunet_plugin_transport_dv_init (void *cls)
378 struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
379 struct GNUNET_TRANSPORT_PluginFunctions *api;
380 struct Plugin *plugin;
382 plugin = GNUNET_malloc (sizeof (struct Plugin));
384 //plugin->service = service;
385 //plugin->server = GNUNET_SERVICE_get_server (service);
387 plugin->dv_handle = GNUNET_DV_connect(env->sched, env->cfg, &handle_dv_message_received, plugin);
389 if (plugin->dv_handle == NULL)
395 api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
397 api->send = &dv_plugin_send;
398 api->disconnect = &dv_plugin_disconnect;
399 api->address_pretty_printer = &dv_plugin_address_pretty_printer;
400 api->check_address = &dv_plugin_address_suggested;
401 api->address_to_string = &address_to_string;
407 * Exit point from the plugin.
410 libgnunet_plugin_transport_dv_done (void *cls)
412 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
413 struct Plugin *plugin = api->cls;
415 GNUNET_free (plugin);
420 /* end of plugin_transport_template.c */