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 3, or (at your
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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.
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17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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22 * @file dv/plugin_transport_dv.c
23 * @brief DV transport service, takes incoming DV requests and deals with
25 * @author Nathan Evans
26 * @author Christian Grothoff
30 #include "gnunet_protocols.h"
31 #include "gnunet_connection_lib.h"
32 #include "gnunet_server_lib.h"
33 #include "gnunet_service_lib.h"
34 #include "gnunet_statistics_service.h"
35 #include "gnunet_dv_service.h"
36 #include "gnunet_transport_service.h"
37 #include "../transport/plugin_transport.h"
40 #define DEBUG_TEMPLATE GNUNET_NO
43 * Encapsulation of all of the state of the plugin.
49 * Session handle for connections.
55 * Stored in a linked list.
60 * Pointer to the global plugin struct.
62 struct Plugin *plugin;
65 * The client (used to identify this connection)
70 * Continuation function to call once the transmission buffer
71 * has again space available. NULL if there is no
72 * continuation to call.
74 GNUNET_TRANSPORT_TransmitContinuation transmit_cont;
77 * Closure for transmit_cont.
79 void *transmit_cont_cls;
82 * To whom are we talking to (set to our identity
83 * if we are still waiting for the welcome message)
85 struct GNUNET_PeerIdentity sender;
88 * At what time did we reset last_received last?
90 struct GNUNET_TIME_Absolute last_quota_update;
93 * How many bytes have we received since the "last_quota_update"
96 uint64_t last_received;
99 * Number of bytes per ms that this peer is allowed
107 * Encapsulation of all of the state of the plugin.
114 struct GNUNET_TRANSPORT_PluginEnvironment *env;
117 * List of open sessions.
119 struct Session *sessions;
124 //struct GNUNET_SERVER_Handle *server;
127 * Handle to the running service.
129 //struct GNUNET_SERVICE_Context *service;
132 * Copy of the handler array where the closures are
133 * set to this struct's instance.
135 struct GNUNET_SERVER_MessageHandler *handlers;
138 * Handle to the DV service
140 struct GNUNET_DV_Handle *dv_handle;
145 * Handler for messages received from the DV service.
147 void handle_dv_message_received (void *cls,
148 struct GNUNET_PeerIdentity *sender,
152 char *sender_address,
153 size_t sender_address_len)
155 struct Plugin *plugin = cls;
156 #if DEBUG_DV_MESSAGES
158 my_id = GNUNET_strdup(GNUNET_i2s(plugin->env->my_identity));
159 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
160 "plugin_transport_dv",
161 _("%s Received message from %s of type %d, distance %u!\n"),
162 my_id, GNUNET_i2s(sender), ntohs(((struct GNUNET_MessageHeader *)msg)->type), distance);
163 GNUNET_free_non_null(my_id);
165 plugin->env->receive(plugin->env->cls,
167 (struct GNUNET_MessageHeader *)msg,
176 /* Question: how does the transport service learn of a newly connected (gossipped about)
177 * DV peer? Should the plugin (here) create a HELLO for that peer and send it along,
178 * or should the DV service create a HELLO and send it to us via the other part?
182 * Function that can be used by the transport service to transmit
183 * a message using the plugin.
186 * @param target who should receive this message
187 * @param priority how important is the message
188 * @param msgbuf the message to transmit
189 * @param msgbuf_size number of bytes in 'msgbuf'
190 * @param timeout when should we time out
191 * @param session the session used
192 * @param addr the address to use (can be NULL if the plugin
193 * is "on its own" (i.e. re-use existing TCP connection))
194 * @param addrlen length of the address in bytes
195 * @param force_address GNUNET_YES if the plugin MUST use the given address,
196 * otherwise the plugin may use other addresses or
197 * existing connections (if available)
198 * @param cont continuation to call once the message has
199 * been transmitted (or if the transport is ready
200 * for the next transmission call; or if the
201 * peer disconnected...)
202 * @param cont_cls closure for cont
203 * @return number of bytes used (on the physical network, with overheads);
204 * -1 on hard errors (i.e. address invalid); 0 is a legal value
205 * and does NOT mean that the message was not transmitted (DV)
208 dv_plugin_send (void *cls,
209 const struct GNUNET_PeerIdentity *target,
212 unsigned int priority,
213 struct GNUNET_TIME_Relative timeout,
214 struct Session *session,
218 GNUNET_TRANSPORT_TransmitContinuation
219 cont, void *cont_cls)
222 struct Plugin *plugin = cls;
224 ret = GNUNET_DV_send(plugin->dv_handle,
240 * Function that can be used to force the plugin to disconnect
241 * from the given peer and cancel all previous transmissions
242 * (and their continuations).
245 * @param target peer from which to disconnect
248 dv_plugin_disconnect (void *cls,
249 const struct GNUNET_PeerIdentity *target)
251 // struct Plugin *plugin = cls;
252 // TODO: Add message type to send to dv service to "disconnect" a peer
257 * Convert the transports address to a nice, human-readable
261 * @param type name of the transport that generated the address
262 * @param addr one of the addresses of the host, NULL for the last address
263 * the specific address format depends on the transport
264 * @param addrlen length of the address
265 * @param numeric should (IP) addresses be displayed in numeric form?
266 * @param timeout after how long should we give up?
267 * @param asc function to call on each string
268 * @param asc_cls closure for asc
271 dv_plugin_address_pretty_printer (void *cls,
276 struct GNUNET_TIME_Relative timeout,
277 GNUNET_TRANSPORT_AddressStringCallback
283 char *addr_buf = (char *)addr;
285 if (addrlen != sizeof(struct GNUNET_PeerIdentity) * 2)
291 dest_peer = GNUNET_strdup(GNUNET_i2s((struct GNUNET_PeerIdentity *)addr));
292 via_peer = GNUNET_strdup(GNUNET_i2s((struct GNUNET_PeerIdentity *)&addr_buf[sizeof(struct GNUNET_PeerIdentity)]));
293 GNUNET_asprintf(&print_string, "DV Peer `%s' via peer`%s'", dest_peer, via_peer);
294 asc (asc_cls, print_string);
296 GNUNET_free(via_peer);
297 GNUNET_free(dest_peer);
298 GNUNET_free(print_string);
303 * Convert the DV address to a pretty string.
306 * @param addr the (hopefully) DV address
307 * @param addrlen the length of the address
309 * @return string representing the DV address
311 static const char *address_to_string (void *cls,
315 static char return_buffer[2 * 4 + 2]; // Two four character peer identity prefixes a ':' and '\0'
317 struct GNUNET_CRYPTO_HashAsciiEncoded peer_hash;
318 struct GNUNET_CRYPTO_HashAsciiEncoded via_hash;
319 struct GNUNET_PeerIdentity *peer;
320 struct GNUNET_PeerIdentity *via;
321 char *addr_buf = (char *)addr;
323 if (addrlen == (2 * sizeof(struct GNUNET_PeerIdentity)))
325 peer = (struct GNUNET_PeerIdentity *)addr_buf;
326 via = (struct GNUNET_PeerIdentity *)&addr_buf[sizeof(struct GNUNET_PeerIdentity)];
328 GNUNET_CRYPTO_hash_to_enc (&peer->hashPubKey, &peer_hash);
329 peer_hash.encoding[4] = '\0';
330 GNUNET_CRYPTO_hash_to_enc (&via->hashPubKey, &via_hash);
331 via_hash.encoding[4] = '\0';
332 GNUNET_snprintf (return_buffer,
333 sizeof (return_buffer),
341 return return_buffer;
345 * Another peer has suggested an address for this peer and transport
346 * plugin. Check that this could be a valid address. This function
347 * is not expected to 'validate' the address in the sense of trying to
348 * connect to it but simply to see if the binary format is technically
349 * legal for establishing a connection to this peer (and make sure that
350 * the address really corresponds to our network connection/settings
351 * and not some potential man-in-the-middle).
354 * @param addr pointer to the address
355 * @param addrlen length of addr
356 * @return GNUNET_OK if this is a plausible address for this peer
357 * and transport, GNUNET_SYSERR if not
361 dv_plugin_check_address (void *cls,
362 const void *addr, size_t addrlen)
364 struct Plugin *plugin = cls;
365 /* Verify that the first peer of this address matches our peer id! */
366 if ((addrlen != (2 * sizeof(struct GNUNET_PeerIdentity))) || (0 != memcmp(addr, plugin->env->my_identity, sizeof(struct GNUNET_PeerIdentity))))
368 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "%s: Address not correct size or identity doesn't match ours!\n", GNUNET_i2s(plugin->env->my_identity));
369 if (addrlen == (2 * sizeof(struct GNUNET_PeerIdentity)))
371 GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Peer in address is %s\n", GNUNET_i2s(addr));
373 return GNUNET_SYSERR;
380 * Entry point for the plugin.
383 libgnunet_plugin_transport_dv_init (void *cls)
385 struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
386 struct GNUNET_TRANSPORT_PluginFunctions *api;
387 struct Plugin *plugin;
389 plugin = GNUNET_malloc (sizeof (struct Plugin));
392 plugin->dv_handle = GNUNET_DV_connect(env->sched, env->cfg, &handle_dv_message_received, plugin);
394 if (plugin->dv_handle == NULL)
400 api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
402 api->send = &dv_plugin_send;
403 api->disconnect = &dv_plugin_disconnect;
404 api->address_pretty_printer = &dv_plugin_address_pretty_printer;
405 api->check_address = &dv_plugin_check_address;
406 api->address_to_string = &address_to_string;
412 * Exit point from the plugin.
415 libgnunet_plugin_transport_dv_done (void *cls)
417 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
418 struct Plugin *plugin = api->cls;
420 if (plugin->dv_handle != NULL)
421 GNUNET_DV_disconnect(plugin->dv_handle);
423 GNUNET_free (plugin);
428 /* end of plugin_transport_template.c */