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
8 option) any later version.
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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.
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,
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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 "gnunet_transport_plugin.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.
148 handle_dv_message_received (void *cls,
149 struct GNUNET_PeerIdentity *sender,
153 char *sender_address, size_t sender_address_len)
155 struct Plugin *plugin = cls;
157 #if DEBUG_DV_MESSAGES
160 my_id = GNUNET_strdup (GNUNET_i2s (plugin->env->my_identity));
161 GNUNET_log_from (GNUNET_ERROR_TYPE_DEBUG,
162 "plugin_transport_dv",
163 _("%s Received message from %s of type %d, distance %u!\n"),
164 my_id, GNUNET_i2s (sender),
165 ntohs (((struct GNUNET_MessageHeader *) msg)->type),
167 GNUNET_free_non_null (my_id);
169 struct GNUNET_TRANSPORT_ATS_Information ats[2];
171 ats[0].type = htonl (GNUNET_TRANSPORT_ATS_QUALITY_NET_DISTANCE);
172 ats[0].value = htonl (distance);
173 ats[1].type = htonl (GNUNET_TRANSPORT_ATS_ARRAY_TERMINATOR);
174 ats[1].value = htonl (0);
176 plugin->env->receive (plugin->env->cls,
178 (struct GNUNET_MessageHeader *) msg,
179 (const struct GNUNET_TRANSPORT_ATS_Information *) &ats,
180 2, NULL, sender_address, sender_address_len);
185 /* Question: how does the transport service learn of a newly connected (gossipped about)
186 * DV peer? Should the plugin (here) create a HELLO for that peer and send it along,
187 * or should the DV service create a HELLO and send it to us via the other part?
191 * Function that can be used by the transport service to transmit
192 * a message using the plugin.
195 * @param target who should receive this message
196 * @param priority how important is the message
197 * @param msgbuf the message to transmit
198 * @param msgbuf_size number of bytes in 'msgbuf'
199 * @param timeout when should we time out
200 * @param session the session used
201 * @param addr the address to use (can be NULL if the plugin
202 * is "on its own" (i.e. re-use existing TCP connection))
203 * @param addrlen length of the address in bytes
204 * @param force_address GNUNET_YES if the plugin MUST use the given address,
205 * otherwise the plugin may use other addresses or
206 * existing connections (if available)
207 * @param cont continuation to call once the message has
208 * been transmitted (or if the transport is ready
209 * for the next transmission call; or if the
210 * peer disconnected...)
211 * @param cont_cls closure for cont
212 * @return number of bytes used (on the physical network, with overheads);
213 * -1 on hard errors (i.e. address invalid); 0 is a legal value
214 * and does NOT mean that the message was not transmitted (DV)
217 dv_plugin_send (void *cls,
218 const struct GNUNET_PeerIdentity *target,
221 unsigned int priority,
222 struct GNUNET_TIME_Relative timeout,
223 struct Session *session,
227 GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls)
230 struct Plugin *plugin = cls;
232 ret = GNUNET_DV_send (plugin->dv_handle,
236 priority, timeout, addr, addrlen, cont, cont_cls);
243 * Function that can be used to force the plugin to disconnect
244 * from the given peer and cancel all previous transmissions
245 * (and their continuations).
248 * @param target peer from which to disconnect
251 dv_plugin_disconnect (void *cls, const struct GNUNET_PeerIdentity *target)
253 // struct Plugin *plugin = cls;
254 // TODO: Add message type to send to dv service to "disconnect" a peer
259 * Convert the transports address to a nice, human-readable
263 * @param type name of the transport that generated the address
264 * @param addr one of the addresses of the host, NULL for the last address
265 * the specific address format depends on the transport
266 * @param addrlen length of the address
267 * @param numeric should (IP) addresses be displayed in numeric form?
268 * @param timeout after how long should we give up?
269 * @param asc function to call on each string
270 * @param asc_cls closure for asc
273 dv_plugin_address_pretty_printer (void *cls,
278 struct GNUNET_TIME_Relative timeout,
279 GNUNET_TRANSPORT_AddressStringCallback
285 char *addr_buf = (char *) addr;
287 if (addrlen != sizeof (struct GNUNET_PeerIdentity) * 2)
294 GNUNET_strdup (GNUNET_i2s ((struct GNUNET_PeerIdentity *) addr));
296 GNUNET_strdup (GNUNET_i2s
297 ((struct GNUNET_PeerIdentity *)
298 &addr_buf[sizeof (struct GNUNET_PeerIdentity)]));
299 GNUNET_asprintf (&print_string, "DV Peer `%s' via peer`%s'", dest_peer,
301 asc (asc_cls, print_string);
303 GNUNET_free (via_peer);
304 GNUNET_free (dest_peer);
305 GNUNET_free (print_string);
310 * Convert the DV address to a pretty string.
313 * @param addr the (hopefully) DV address
314 * @param addrlen the length of the address
316 * @return string representing the DV address
319 address_to_string (void *cls, const void *addr, size_t addrlen)
321 static char return_buffer[2 * 4 + 2]; // Two four character peer identity prefixes a ':' and '\0'
323 struct GNUNET_CRYPTO_HashAsciiEncoded peer_hash;
324 struct GNUNET_CRYPTO_HashAsciiEncoded via_hash;
325 struct GNUNET_PeerIdentity *peer;
326 struct GNUNET_PeerIdentity *via;
327 char *addr_buf = (char *) addr;
329 if (addrlen == (2 * sizeof (struct GNUNET_PeerIdentity)))
331 peer = (struct GNUNET_PeerIdentity *) addr_buf;
333 (struct GNUNET_PeerIdentity *)
334 &addr_buf[sizeof (struct GNUNET_PeerIdentity)];
336 GNUNET_CRYPTO_hash_to_enc (&peer->hashPubKey, &peer_hash);
337 peer_hash.encoding[4] = '\0';
338 GNUNET_CRYPTO_hash_to_enc (&via->hashPubKey, &via_hash);
339 via_hash.encoding[4] = '\0';
340 GNUNET_snprintf (return_buffer,
341 sizeof (return_buffer), "%s:%s", &peer_hash, &via_hash);
346 return return_buffer;
350 * Another peer has suggested an address for this peer and transport
351 * plugin. Check that this could be a valid address. This function
352 * is not expected to 'validate' the address in the sense of trying to
353 * connect to it but simply to see if the binary format is technically
354 * legal for establishing a connection to this peer (and make sure that
355 * the address really corresponds to our network connection/settings
356 * and not some potential man-in-the-middle).
359 * @param addr pointer to the address
360 * @param addrlen length of addr
361 * @return GNUNET_OK if this is a plausible address for this peer
362 * and transport, GNUNET_SYSERR if not
366 dv_plugin_check_address (void *cls, const void *addr, size_t addrlen)
368 struct Plugin *plugin = cls;
370 /* Verify that the first peer of this address matches our peer id! */
371 if ((addrlen != (2 * sizeof (struct GNUNET_PeerIdentity))) ||
373 memcmp (addr, plugin->env->my_identity,
374 sizeof (struct GNUNET_PeerIdentity))))
376 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
377 "%s: Address not correct size or identity doesn't match ours!\n",
378 GNUNET_i2s (plugin->env->my_identity));
379 if (addrlen == (2 * sizeof (struct GNUNET_PeerIdentity)))
381 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Peer in address is %s\n",
384 return GNUNET_SYSERR;
391 * Entry point for the plugin.
394 libgnunet_plugin_transport_dv_init (void *cls)
396 struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
397 struct GNUNET_TRANSPORT_PluginFunctions *api;
398 struct Plugin *plugin;
400 plugin = GNUNET_malloc (sizeof (struct Plugin));
404 GNUNET_DV_connect (env->cfg, &handle_dv_message_received, plugin);
406 if (plugin->dv_handle == NULL)
408 GNUNET_free (plugin);
412 api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
414 api->send = &dv_plugin_send;
415 api->disconnect = &dv_plugin_disconnect;
416 api->address_pretty_printer = &dv_plugin_address_pretty_printer;
417 api->check_address = &dv_plugin_check_address;
418 api->address_to_string = &address_to_string;
424 * Exit point from the plugin.
427 libgnunet_plugin_transport_dv_done (void *cls)
429 struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
430 struct Plugin *plugin = api->cls;
432 if (plugin->dv_handle != NULL)
433 GNUNET_DV_disconnect (plugin->dv_handle);
435 GNUNET_free (plugin);
440 /* end of plugin_transport_template.c */