2 This file is part of GNUnet.
3 Copyright (C) 2013 GNUnet e.V.
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.
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., 51 Franklin Street, Fifth Floor,
18 Boston, MA 02110-1301, USA.
23 #include "gnunet_util_lib.h"
25 #include "gnunet_dht_service.h"
26 #include "gnunet_statistics_service.h"
28 #include "cadet_path.h"
29 #include "gnunet-service-cadet_dht.h"
30 #include "gnunet-service-cadet_peer.h"
31 #include "gnunet-service-cadet_hello.h"
33 #define LOG(level, ...) GNUNET_log_from (level,"cadet-dht",__VA_ARGS__)
36 /******************************************************************************/
37 /******************************** STRUCTS **********************************/
38 /******************************************************************************/
41 * Handle for DHT searches.
43 struct GCD_search_handle
45 /** DHT_GET handle. */
46 struct GNUNET_DHT_GetHandle *dhtget;
48 /** Provided callback to call when a path is found. */
49 GCD_search_callback callback;
51 /** Provided closure. */
54 /** Peer ID searched for */
55 GNUNET_PEER_Id peer_id;
59 /******************************************************************************/
60 /******************************* GLOBALS ***********************************/
61 /******************************************************************************/
64 * Global handle to the statistics service.
66 extern struct GNUNET_STATISTICS_Handle *stats;
69 * Own ID (short value).
71 extern GNUNET_PEER_Id myid;
74 * Own ID (full value).
76 extern struct GNUNET_PeerIdentity my_full_id;
81 static struct GNUNET_DHT_Handle *dht_handle;
84 * How often to PUT own ID in the DHT.
86 static struct GNUNET_TIME_Relative id_announce_time;
89 * DHT replication level, see DHT API: GNUNET_DHT_get_start, GNUNET_DHT_put.
91 static unsigned long long dht_replication_level;
94 * Task to periodically announce itself in the network.
96 static struct GNUNET_SCHEDULER_Task * announce_id_task;
99 * Delay for the next ID announce.
101 static struct GNUNET_TIME_Relative announce_delay;
104 * GET requests to stop on shutdown.
106 static struct GNUNET_CONTAINER_MultiHashMap32 *get_requests;
108 /******************************************************************************/
109 /******************************** STATIC ***********************************/
110 /******************************************************************************/
114 * Build a PeerPath from the paths returned from the DHT, reversing the paths
115 * to obtain a local peer -> destination path and interning the peer ids.
117 * @return Newly allocated and created path
119 * FIXME refactor and use build_path_from_peer_ids
121 static struct CadetPeerPath *
122 path_build_from_dht (const struct GNUNET_PeerIdentity *get_path,
123 unsigned int get_path_length,
124 const struct GNUNET_PeerIdentity *put_path,
125 unsigned int put_path_length)
127 size_t size = get_path_length + put_path_length + 1;
128 struct GNUNET_PeerIdentity peers[size];
129 const struct GNUNET_PeerIdentity *peer;
130 struct CadetPeerPath *p;
131 unsigned int own_pos;
134 peers[0] = my_full_id;
135 LOG (GNUNET_ERROR_TYPE_DEBUG, " GET has %d hops.\n", get_path_length);
136 for (i = 0 ; i < get_path_length; i++)
138 peer = &get_path[get_path_length - i - 1];
139 LOG (GNUNET_ERROR_TYPE_DEBUG, " From GET: %s\n", GNUNET_i2s (peer));
140 peers[i + 1] = *peer;
142 for (i = 0 ; i < put_path_length; i++)
144 peer = &put_path[put_path_length - i - 1];
145 LOG (GNUNET_ERROR_TYPE_DEBUG, " From PUT: %s\n", GNUNET_i2s (peer));
146 peers[i + get_path_length + 1] = *peer;
148 p = path_build_from_peer_ids (peers, size, myid, &own_pos);
154 * Function to process paths received for a new peer addition. The recorded
155 * paths form the initial tunnel, which can be optimized later.
156 * Called on each result obtained for the DHT search.
159 * @param exp when will this value expire
160 * @param key key of the result
161 * @param get_path path of the get request
162 * @param get_path_length lenght of @a get_path
163 * @param put_path path of the put request
164 * @param put_path_length length of the @a put_path
165 * @param type type of the result
166 * @param size number of bytes in data
167 * @param data pointer to the result data
170 dht_get_id_handler (void *cls, struct GNUNET_TIME_Absolute exp,
171 const struct GNUNET_HashCode * key,
172 const struct GNUNET_PeerIdentity *get_path,
173 unsigned int get_path_length,
174 const struct GNUNET_PeerIdentity *put_path,
175 unsigned int put_path_length, enum GNUNET_BLOCK_Type type,
176 size_t size, const void *data)
178 struct GCD_search_handle *h = cls;
179 struct GNUNET_HELLO_Message *hello;
180 struct CadetPeerPath *p;
181 struct CadetPeer *peer;
184 p = path_build_from_dht (get_path, get_path_length,
185 put_path, put_path_length);
193 LOG (GNUNET_ERROR_TYPE_INFO,
194 "Got path from DHT: %s\n",
196 GNUNET_free_non_null (s);
198 peer = GCP_get_short (p->peers[p->length - 1], GNUNET_YES);
199 LOG (GNUNET_ERROR_TYPE_DEBUG,
200 "Got HELLO for %s\n",
202 h->callback (h->cls, p);
204 hello = (struct GNUNET_HELLO_Message *) data;
205 GCP_set_hello (peer, hello);
206 GCP_try_connect (peer);
211 * Periodically announce self id in the DHT
216 announce_id (void *cls)
218 struct GNUNET_HashCode phash;
219 const struct GNUNET_HELLO_Message *hello;
221 struct GNUNET_TIME_Absolute expiration;
222 struct GNUNET_TIME_Relative next_put;
224 announce_id_task = NULL;
225 LOG (GNUNET_ERROR_TYPE_DEBUG, "Announce ID\n");
226 hello = GCH_get_mine ();
227 size = NULL != hello ? GNUNET_HELLO_size (hello) : 0;
228 if (NULL == hello || 0 == size)
230 /* Peerinfo gave us no hello yet, try again soon. */
231 LOG (GNUNET_ERROR_TYPE_INFO, " no hello, waiting!\n");
232 GNUNET_STATISTICS_update (stats, "# DHT announce skipped (no hello)",
234 expiration = GNUNET_TIME_absolute_add (GNUNET_TIME_absolute_get (),
236 announce_delay = GNUNET_TIME_STD_BACKOFF (announce_delay);
240 expiration = GNUNET_HELLO_get_last_expiration (hello);
241 announce_delay = GNUNET_TIME_UNIT_SECONDS;
244 LOG (GNUNET_ERROR_TYPE_DEBUG, "Hello %p size: %u\n", hello, size);
245 GNUNET_STATISTICS_update (stats, "# DHT announce",
247 memset (&phash, 0, sizeof (phash));
248 GNUNET_memcpy (&phash, &my_full_id, sizeof (my_full_id));
249 GNUNET_DHT_put (dht_handle, /* DHT handle */
250 &phash, /* Key to use */
251 dht_replication_level, /* Replication level */
252 GNUNET_DHT_RO_RECORD_ROUTE
253 | GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE, /* DHT options */
254 GNUNET_BLOCK_TYPE_DHT_HELLO, /* Block type */
255 size, /* Size of the data */
256 (const char *) hello, /* Data itself */
257 expiration, /* Data expiration */
258 NULL, /* Continuation */
259 NULL); /* Continuation closure */
261 /* Call again in id_announce_time, unless HELLO expires first,
262 * but wait at least 1s. */
263 next_put = GNUNET_TIME_absolute_get_remaining (expiration);
264 next_put = GNUNET_TIME_relative_min (next_put, id_announce_time);
265 next_put = GNUNET_TIME_relative_max (next_put, GNUNET_TIME_UNIT_SECONDS);
266 announce_id_task = GNUNET_SCHEDULER_add_delayed (next_put, &announce_id, cls);
270 * Iterator over hash map entries and stop GET requests before disconnecting
273 * @param cls Closure (unused)
274 * @param key Current peer ID.
275 * @param value Value in the hash map (GCD_search_handle).
277 * @return #GNUNET_YES, we should continue to iterate,
284 struct GCD_search_handle *h = value;
291 /******************************************************************************/
292 /******************************** API ***********************************/
293 /******************************************************************************/
296 * Initialize the DHT subsystem.
298 * @param c Configuration.
301 GCD_init (const struct GNUNET_CONFIGURATION_Handle *c)
303 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
305 GNUNET_CONFIGURATION_get_value_number (c, "CADET",
306 "DHT_REPLICATION_LEVEL",
307 &dht_replication_level))
309 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_WARNING, "CADET",
310 "DHT_REPLICATION_LEVEL", "USING DEFAULT");
311 dht_replication_level = 3;
315 GNUNET_CONFIGURATION_get_value_time (c, "CADET", "ID_ANNOUNCE_TIME",
318 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR, "CADET",
319 "ID_ANNOUNCE_TIME", "MISSING");
320 GNUNET_SCHEDULER_shutdown ();
324 dht_handle = GNUNET_DHT_connect (c, 64);
325 if (NULL == dht_handle)
330 announce_delay = GNUNET_TIME_UNIT_SECONDS;
331 announce_id_task = GNUNET_SCHEDULER_add_now (&announce_id, NULL);
332 get_requests = GNUNET_CONTAINER_multihashmap32_create (32);
337 * Shut down the DHT subsystem.
342 LOG (GNUNET_ERROR_TYPE_DEBUG, "Shutting down DHT\n");
343 GNUNET_CONTAINER_multihashmap32_iterate (get_requests, &stop_get, NULL);
344 GNUNET_CONTAINER_multihashmap32_destroy (get_requests);
345 if (dht_handle != NULL)
347 GNUNET_DHT_disconnect (dht_handle);
350 if (NULL != announce_id_task)
352 GNUNET_SCHEDULER_cancel (announce_id_task);
353 announce_id_task = NULL;
357 struct GCD_search_handle *
358 GCD_search (const struct GNUNET_PeerIdentity *peer_id,
359 GCD_search_callback callback, void *cls)
361 struct GNUNET_HashCode phash;
362 struct GCD_search_handle *h;
364 LOG (GNUNET_ERROR_TYPE_DEBUG, "Starting DHT GET for peer %s\n",
365 GNUNET_i2s (peer_id));
366 GNUNET_STATISTICS_update (stats, "# DHT search", 1, GNUNET_NO);
367 memset (&phash, 0, sizeof (phash));
368 GNUNET_memcpy (&phash, peer_id, sizeof (*peer_id));
369 h = GNUNET_new (struct GCD_search_handle);
370 h->peer_id = GNUNET_PEER_intern (peer_id);
371 h->callback = callback;
373 h->dhtget = GNUNET_DHT_get_start (dht_handle, /* handle */
374 GNUNET_BLOCK_TYPE_DHT_HELLO, /* type */
375 &phash, /* key to search */
376 dht_replication_level, /* replication level */
377 GNUNET_DHT_RO_RECORD_ROUTE |
378 GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE,
381 &dht_get_id_handler, h);
382 GNUNET_CONTAINER_multihashmap32_put (get_requests, h->peer_id, h,
383 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST);
389 GCD_search_stop (struct GCD_search_handle *h)
391 GNUNET_break (GNUNET_OK ==
392 GNUNET_CONTAINER_multihashmap32_remove (get_requests,
394 GNUNET_DHT_get_stop (h->dhtget);