diff options
Diffstat (limited to 'src/namecache/namecache_api.c')
-rw-r--r-- | src/namecache/namecache_api.c | 567 |
1 files changed, 0 insertions, 567 deletions
diff --git a/src/namecache/namecache_api.c b/src/namecache/namecache_api.c deleted file mode 100644 index 70c848037..000000000 --- a/src/namecache/namecache_api.c +++ /dev/null | |||
@@ -1,567 +0,0 @@ | |||
1 | /* | ||
2 | This file is part of GNUnet. | ||
3 | Copyright (C) 2010-2013, 2016 GNUnet e.V. | ||
4 | |||
5 | GNUnet is free software: you can redistribute it and/or modify it | ||
6 | under the terms of the GNU Affero General Public License as published | ||
7 | by the Free Software Foundation, either version 3 of the License, | ||
8 | or (at your 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 | Affero General Public License for more details. | ||
14 | |||
15 | You should have received a copy of the GNU Affero General Public License | ||
16 | along with this program. If not, see <http://www.gnu.org/licenses/>. | ||
17 | |||
18 | SPDX-License-Identifier: AGPL3.0-or-later | ||
19 | */ | ||
20 | |||
21 | /** | ||
22 | * @file namecache/namecache_api.c | ||
23 | * @brief API to access the NAMECACHE service | ||
24 | * @author Martin Schanzenbach | ||
25 | * @author Matthias Wachs | ||
26 | * @author Christian Grothoff | ||
27 | */ | ||
28 | |||
29 | #include "platform.h" | ||
30 | #include "gnunet_util_lib.h" | ||
31 | #include "gnunet_crypto_lib.h" | ||
32 | #include "gnunet_constants.h" | ||
33 | #include "gnunet_dnsparser_lib.h" | ||
34 | #include "gnunet_gnsrecord_lib.h" | ||
35 | #include "gnunet_signatures.h" | ||
36 | #include "gnunet_namecache_service.h" | ||
37 | #include "namecache.h" | ||
38 | |||
39 | |||
40 | #define LOG(kind, ...) GNUNET_log_from (kind, "namecache-api", __VA_ARGS__) | ||
41 | |||
42 | |||
43 | /** | ||
44 | * An QueueEntry used to store information for a pending | ||
45 | * NAMECACHE record operation | ||
46 | */ | ||
47 | struct GNUNET_NAMECACHE_QueueEntry | ||
48 | { | ||
49 | /** | ||
50 | * Kept in a DLL. | ||
51 | */ | ||
52 | struct GNUNET_NAMECACHE_QueueEntry *next; | ||
53 | |||
54 | /** | ||
55 | * Kept in a DLL. | ||
56 | */ | ||
57 | struct GNUNET_NAMECACHE_QueueEntry *prev; | ||
58 | |||
59 | /** | ||
60 | * Main handle to access the namecache. | ||
61 | */ | ||
62 | struct GNUNET_NAMECACHE_Handle *nsh; | ||
63 | |||
64 | /** | ||
65 | * Continuation to call | ||
66 | */ | ||
67 | GNUNET_NAMECACHE_ContinuationWithStatus cont; | ||
68 | |||
69 | /** | ||
70 | * Closure for @e cont. | ||
71 | */ | ||
72 | void *cont_cls; | ||
73 | |||
74 | /** | ||
75 | * Function to call with the blocks we get back; or NULL. | ||
76 | */ | ||
77 | GNUNET_NAMECACHE_BlockProcessor block_proc; | ||
78 | |||
79 | /** | ||
80 | * Closure for @e block_proc. | ||
81 | */ | ||
82 | void *block_proc_cls; | ||
83 | |||
84 | /** | ||
85 | * The operation id this zone iteration operation has | ||
86 | */ | ||
87 | uint32_t op_id; | ||
88 | }; | ||
89 | |||
90 | |||
91 | /** | ||
92 | * Connection to the NAMECACHE service. | ||
93 | */ | ||
94 | struct GNUNET_NAMECACHE_Handle | ||
95 | { | ||
96 | /** | ||
97 | * Configuration to use. | ||
98 | */ | ||
99 | const struct GNUNET_CONFIGURATION_Handle *cfg; | ||
100 | |||
101 | /** | ||
102 | * Message queue to service. | ||
103 | */ | ||
104 | struct GNUNET_MQ_Handle *mq; | ||
105 | |||
106 | /** | ||
107 | * Currently pending transmission request (or NULL). | ||
108 | */ | ||
109 | struct GNUNET_CLIENT_TransmitHandle *th; | ||
110 | |||
111 | /** | ||
112 | * Head of pending namecache queue entries | ||
113 | */ | ||
114 | struct GNUNET_NAMECACHE_QueueEntry *op_head; | ||
115 | |||
116 | /** | ||
117 | * Tail of pending namecache queue entries | ||
118 | */ | ||
119 | struct GNUNET_NAMECACHE_QueueEntry *op_tail; | ||
120 | |||
121 | /** | ||
122 | * Reconnect task | ||
123 | */ | ||
124 | struct GNUNET_SCHEDULER_Task *reconnect_task; | ||
125 | |||
126 | /** | ||
127 | * Delay introduced before we reconnect. | ||
128 | */ | ||
129 | struct GNUNET_TIME_Relative reconnect_delay; | ||
130 | |||
131 | /** | ||
132 | * Should we reconnect to service due to some serious error? | ||
133 | */ | ||
134 | int reconnect; | ||
135 | |||
136 | /** | ||
137 | * The last operation id used for a NAMECACHE operation | ||
138 | */ | ||
139 | uint32_t last_op_id_used; | ||
140 | }; | ||
141 | |||
142 | |||
143 | /** | ||
144 | * Disconnect from service and then reconnect. | ||
145 | * | ||
146 | * @param h our handle | ||
147 | */ | ||
148 | static void | ||
149 | force_reconnect (struct GNUNET_NAMECACHE_Handle *h); | ||
150 | |||
151 | |||
152 | /** | ||
153 | * Find queue entry for the given @a rid. | ||
154 | * | ||
155 | * @param h handle to search | ||
156 | * @param rid request ID to look for | ||
157 | * @return NULL if not found, otherwise the queue entry (removed from the queue) | ||
158 | */ | ||
159 | static struct GNUNET_NAMECACHE_QueueEntry * | ||
160 | find_qe (struct GNUNET_NAMECACHE_Handle *h, | ||
161 | uint32_t rid) | ||
162 | { | ||
163 | struct GNUNET_NAMECACHE_QueueEntry *qe; | ||
164 | |||
165 | for (qe = h->op_head; qe != NULL; qe = qe->next) | ||
166 | { | ||
167 | if (qe->op_id == rid) | ||
168 | { | ||
169 | GNUNET_CONTAINER_DLL_remove (h->op_head, | ||
170 | h->op_tail, | ||
171 | qe); | ||
172 | return qe; | ||
173 | } | ||
174 | } | ||
175 | return NULL; | ||
176 | } | ||
177 | |||
178 | |||
179 | /** | ||
180 | * Handle an incoming message of type | ||
181 | * #GNUNET_MESSAGE_TYPE_NAMECACHE_LOOKUP_BLOCK_RESPONSE. | ||
182 | * | ||
183 | * @param cls the `struct GNUNET_NAMECACHE_Handle` | ||
184 | * @param msg the message we received | ||
185 | */ | ||
186 | static int | ||
187 | check_lookup_block_response (void *cls, | ||
188 | const struct LookupBlockResponseMessage *msg) | ||
189 | { | ||
190 | /* any length will do, format validation is in handler */ | ||
191 | return GNUNET_OK; | ||
192 | } | ||
193 | |||
194 | |||
195 | /** | ||
196 | * Handle an incoming message of type | ||
197 | * #GNUNET_MESSAGE_TYPE_NAMECACHE_LOOKUP_BLOCK_RESPONSE. | ||
198 | * | ||
199 | * @param cls the `struct GNUNET_NAMECACHE_Handle` | ||
200 | * @param msg the message we received | ||
201 | */ | ||
202 | static void | ||
203 | handle_lookup_block_response (void *cls, | ||
204 | const struct LookupBlockResponseMessage *msg) | ||
205 | { | ||
206 | struct GNUNET_NAMECACHE_Handle *h = cls; | ||
207 | size_t size; | ||
208 | struct GNUNET_NAMECACHE_QueueEntry *qe; | ||
209 | |||
210 | LOG (GNUNET_ERROR_TYPE_DEBUG, | ||
211 | "Received LOOKUP_BLOCK_RESPONSE\n"); | ||
212 | qe = find_qe (h, | ||
213 | ntohl (msg->gns_header.r_id)); | ||
214 | if (NULL == qe) | ||
215 | return; | ||
216 | if (0 == GNUNET_TIME_absolute_ntoh (msg->expire).abs_value_us) | ||
217 | { | ||
218 | /* no match found */ | ||
219 | if (NULL != qe->block_proc) | ||
220 | qe->block_proc (qe->block_proc_cls, | ||
221 | NULL); | ||
222 | GNUNET_free (qe); | ||
223 | return; | ||
224 | } | ||
225 | size = ntohs (msg->gns_header.header.size) | ||
226 | - sizeof(struct LookupBlockResponseMessage); | ||
227 | { | ||
228 | char buf[size] GNUNET_ALIGN; | ||
229 | struct GNUNET_GNSRECORD_Block *block; | ||
230 | |||
231 | memset (buf, 0, size); | ||
232 | block = (struct GNUNET_GNSRECORD_Block *) buf; | ||
233 | GNUNET_memcpy (block, | ||
234 | &msg[1], | ||
235 | size); | ||
236 | if (GNUNET_OK != | ||
237 | GNUNET_GNSRECORD_block_verify (block)) | ||
238 | { | ||
239 | GNUNET_break (0); | ||
240 | if (NULL != qe->block_proc) | ||
241 | qe->block_proc (qe->block_proc_cls, | ||
242 | NULL); | ||
243 | force_reconnect (h); | ||
244 | } | ||
245 | else | ||
246 | { | ||
247 | if (NULL != qe->block_proc) | ||
248 | qe->block_proc (qe->block_proc_cls, | ||
249 | block); | ||
250 | } | ||
251 | } | ||
252 | GNUNET_free (qe); | ||
253 | } | ||
254 | |||
255 | |||
256 | /** | ||
257 | * Handle an incoming message of type | ||
258 | * #GNUNET_MESSAGE_TYPE_NAMECACHE_BLOCK_CACHE_RESPONSE | ||
259 | * | ||
260 | * @param cls the `struct GNUNET_NAMECACHE_Handle` | ||
261 | * @param msg the message we received | ||
262 | * @param size the message size | ||
263 | * @return #GNUNET_OK on success, #GNUNET_SYSERR on error and we did NOT notify the client | ||
264 | */ | ||
265 | static void | ||
266 | handle_block_cache_response (void *cls, | ||
267 | const struct BlockCacheResponseMessage *msg) | ||
268 | { | ||
269 | struct GNUNET_NAMECACHE_Handle *h = cls; | ||
270 | struct GNUNET_NAMECACHE_QueueEntry *qe; | ||
271 | int res; | ||
272 | |||
273 | LOG (GNUNET_ERROR_TYPE_DEBUG, | ||
274 | "Received BLOCK_CACHE_RESPONSE\n"); | ||
275 | qe = find_qe (h, | ||
276 | ntohl (msg->gns_header.r_id)); | ||
277 | if (NULL == qe) | ||
278 | return; | ||
279 | res = ntohl (msg->op_result); | ||
280 | /* TODO: add actual error message from namecache to response... */ | ||
281 | if (NULL != qe->cont) | ||
282 | qe->cont (qe->cont_cls, | ||
283 | res, | ||
284 | (GNUNET_OK == res) | ||
285 | ? NULL | ||
286 | : _ ("Namecache failed to cache block")); | ||
287 | GNUNET_free (qe); | ||
288 | } | ||
289 | |||
290 | |||
291 | /** | ||
292 | * Generic error handler, called with the appropriate error code and | ||
293 | * the same closure specified at the creation of the message queue. | ||
294 | * Not every message queue implementation supports an error handler. | ||
295 | * | ||
296 | * @param cls closure with the `struct GNUNET_NAMECACHE_Handle *` | ||
297 | * @param error error code | ||
298 | */ | ||
299 | static void | ||
300 | mq_error_handler (void *cls, | ||
301 | enum GNUNET_MQ_Error error) | ||
302 | { | ||
303 | struct GNUNET_NAMECACHE_Handle *h = cls; | ||
304 | |||
305 | force_reconnect (h); | ||
306 | } | ||
307 | |||
308 | |||
309 | /** | ||
310 | * Reconnect to namecache service. | ||
311 | * | ||
312 | * @param h the handle to the NAMECACHE service | ||
313 | */ | ||
314 | static void | ||
315 | reconnect (struct GNUNET_NAMECACHE_Handle *h) | ||
316 | { | ||
317 | struct GNUNET_MQ_MessageHandler handlers[] = { | ||
318 | GNUNET_MQ_hd_var_size (lookup_block_response, | ||
319 | GNUNET_MESSAGE_TYPE_NAMECACHE_LOOKUP_BLOCK_RESPONSE, | ||
320 | struct LookupBlockResponseMessage, | ||
321 | h), | ||
322 | GNUNET_MQ_hd_fixed_size (block_cache_response, | ||
323 | GNUNET_MESSAGE_TYPE_NAMECACHE_BLOCK_CACHE_RESPONSE, | ||
324 | struct BlockCacheResponseMessage, | ||
325 | h), | ||
326 | GNUNET_MQ_handler_end () | ||
327 | }; | ||
328 | |||
329 | GNUNET_assert (NULL == h->mq); | ||
330 | h->mq = GNUNET_CLIENT_connect (h->cfg, | ||
331 | "namecache", | ||
332 | handlers, | ||
333 | &mq_error_handler, | ||
334 | h); | ||
335 | } | ||
336 | |||
337 | |||
338 | /** | ||
339 | * Re-establish the connection to the service. | ||
340 | * | ||
341 | * @param cls handle to use to re-connect. | ||
342 | */ | ||
343 | static void | ||
344 | reconnect_task (void *cls) | ||
345 | { | ||
346 | struct GNUNET_NAMECACHE_Handle *h = cls; | ||
347 | |||
348 | h->reconnect_task = NULL; | ||
349 | reconnect (h); | ||
350 | } | ||
351 | |||
352 | |||
353 | /** | ||
354 | * Disconnect from service and then reconnect. | ||
355 | * | ||
356 | * @param h our handle | ||
357 | */ | ||
358 | static void | ||
359 | force_reconnect (struct GNUNET_NAMECACHE_Handle *h) | ||
360 | { | ||
361 | struct GNUNET_NAMECACHE_QueueEntry *qe; | ||
362 | |||
363 | h->reconnect = GNUNET_NO; | ||
364 | GNUNET_MQ_destroy (h->mq); | ||
365 | h->mq = NULL; | ||
366 | while (NULL != (qe = h->op_head)) | ||
367 | { | ||
368 | GNUNET_CONTAINER_DLL_remove (h->op_head, | ||
369 | h->op_tail, | ||
370 | qe); | ||
371 | if (NULL != qe->cont) | ||
372 | qe->cont (qe->cont_cls, | ||
373 | GNUNET_SYSERR, | ||
374 | _ ("Error communicating with namecache service")); | ||
375 | GNUNET_free (qe); | ||
376 | } | ||
377 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
378 | "Reconnecting to namecache\n"); | ||
379 | h->reconnect_delay = GNUNET_TIME_STD_BACKOFF (h->reconnect_delay); | ||
380 | h->reconnect_task = GNUNET_SCHEDULER_add_delayed (h->reconnect_delay, | ||
381 | &reconnect_task, | ||
382 | h); | ||
383 | } | ||
384 | |||
385 | |||
386 | /** | ||
387 | * Get a fresh operation id to distinguish between namecache requests | ||
388 | * | ||
389 | * @param h the namecache handle | ||
390 | * @return next operation id to use | ||
391 | */ | ||
392 | static uint32_t | ||
393 | get_op_id (struct GNUNET_NAMECACHE_Handle *h) | ||
394 | { | ||
395 | return h->last_op_id_used++; | ||
396 | } | ||
397 | |||
398 | |||
399 | /** | ||
400 | * Initialize the connection with the NAMECACHE service. | ||
401 | * | ||
402 | * @param cfg configuration to use | ||
403 | * @return handle to the GNS service, or NULL on error | ||
404 | */ | ||
405 | struct GNUNET_NAMECACHE_Handle * | ||
406 | GNUNET_NAMECACHE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg) | ||
407 | { | ||
408 | struct GNUNET_NAMECACHE_Handle *h; | ||
409 | |||
410 | h = GNUNET_new (struct GNUNET_NAMECACHE_Handle); | ||
411 | h->cfg = cfg; | ||
412 | reconnect (h); | ||
413 | if (NULL == h->mq) | ||
414 | { | ||
415 | GNUNET_free (h); | ||
416 | return NULL; | ||
417 | } | ||
418 | return h; | ||
419 | } | ||
420 | |||
421 | |||
422 | /** | ||
423 | * Disconnect from the namecache service (and free associated | ||
424 | * resources). | ||
425 | * | ||
426 | * @param h handle to the namecache | ||
427 | */ | ||
428 | void | ||
429 | GNUNET_NAMECACHE_disconnect (struct GNUNET_NAMECACHE_Handle *h) | ||
430 | { | ||
431 | struct GNUNET_NAMECACHE_QueueEntry *q; | ||
432 | |||
433 | GNUNET_break (NULL == h->op_head); | ||
434 | while (NULL != (q = h->op_head)) | ||
435 | { | ||
436 | GNUNET_CONTAINER_DLL_remove (h->op_head, | ||
437 | h->op_tail, | ||
438 | q); | ||
439 | GNUNET_free (q); | ||
440 | } | ||
441 | if (NULL != h->mq) | ||
442 | { | ||
443 | GNUNET_MQ_destroy (h->mq); | ||
444 | h->mq = NULL; | ||
445 | } | ||
446 | if (NULL != h->reconnect_task) | ||
447 | { | ||
448 | GNUNET_SCHEDULER_cancel (h->reconnect_task); | ||
449 | h->reconnect_task = NULL; | ||
450 | } | ||
451 | GNUNET_free (h); | ||
452 | } | ||
453 | |||
454 | |||
455 | /** | ||
456 | * Store an item in the namecache. If the item is already present, | ||
457 | * it is replaced with the new record. | ||
458 | * | ||
459 | * @param h handle to the namecache | ||
460 | * @param block block to store | ||
461 | * @param cont continuation to call when done | ||
462 | * @param cont_cls closure for @a cont | ||
463 | * @return handle to abort the request, NULL on error | ||
464 | */ | ||
465 | struct GNUNET_NAMECACHE_QueueEntry * | ||
466 | GNUNET_NAMECACHE_block_cache (struct GNUNET_NAMECACHE_Handle *h, | ||
467 | const struct GNUNET_GNSRECORD_Block *block, | ||
468 | GNUNET_NAMECACHE_ContinuationWithStatus cont, | ||
469 | void *cont_cls) | ||
470 | { | ||
471 | struct GNUNET_NAMECACHE_QueueEntry *qe; | ||
472 | struct BlockCacheMessage *msg; | ||
473 | struct GNUNET_MQ_Envelope *env; | ||
474 | uint32_t rid; | ||
475 | size_t blen; | ||
476 | |||
477 | if (NULL == h->mq) | ||
478 | return NULL; | ||
479 | blen = GNUNET_GNSRECORD_block_get_size (block); | ||
480 | rid = get_op_id (h); | ||
481 | qe = GNUNET_new (struct GNUNET_NAMECACHE_QueueEntry); | ||
482 | qe->nsh = h; | ||
483 | qe->cont = cont; | ||
484 | qe->cont_cls = cont_cls; | ||
485 | qe->op_id = rid; | ||
486 | GNUNET_CONTAINER_DLL_insert_tail (h->op_head, | ||
487 | h->op_tail, | ||
488 | qe); | ||
489 | /* send msg */ | ||
490 | env = GNUNET_MQ_msg_extra (msg, | ||
491 | blen, | ||
492 | GNUNET_MESSAGE_TYPE_NAMECACHE_BLOCK_CACHE); | ||
493 | msg->gns_header.r_id = htonl (rid); | ||
494 | GNUNET_memcpy (&msg[1], | ||
495 | block, | ||
496 | blen); | ||
497 | GNUNET_MQ_send (h->mq, | ||
498 | env); | ||
499 | return qe; | ||
500 | } | ||
501 | |||
502 | |||
503 | /** | ||
504 | * Get a result for a particular key from the namecache. The processor | ||
505 | * will only be called once. | ||
506 | * | ||
507 | * @param h handle to the namecache | ||
508 | * @param derived_hash hash of zone key combined with name to lookup | ||
509 | * @param proc function to call on the matching block, or with | ||
510 | * NULL if there is no matching block | ||
511 | * @param proc_cls closure for @a proc | ||
512 | * @return a handle that can be used to cancel, NULL on error | ||
513 | */ | ||
514 | struct GNUNET_NAMECACHE_QueueEntry * | ||
515 | GNUNET_NAMECACHE_lookup_block (struct GNUNET_NAMECACHE_Handle *h, | ||
516 | const struct GNUNET_HashCode *derived_hash, | ||
517 | GNUNET_NAMECACHE_BlockProcessor proc, | ||
518 | void *proc_cls) | ||
519 | { | ||
520 | struct GNUNET_NAMECACHE_QueueEntry *qe; | ||
521 | struct LookupBlockMessage *msg; | ||
522 | struct GNUNET_MQ_Envelope *env; | ||
523 | uint32_t rid; | ||
524 | |||
525 | if (NULL == h->mq) | ||
526 | return NULL; | ||
527 | LOG (GNUNET_ERROR_TYPE_DEBUG, | ||
528 | "Looking for block under %s\n", | ||
529 | GNUNET_h2s (derived_hash)); | ||
530 | rid = get_op_id (h); | ||
531 | qe = GNUNET_new (struct GNUNET_NAMECACHE_QueueEntry); | ||
532 | qe->nsh = h; | ||
533 | qe->block_proc = proc; | ||
534 | qe->block_proc_cls = proc_cls; | ||
535 | qe->op_id = rid; | ||
536 | GNUNET_CONTAINER_DLL_insert_tail (h->op_head, | ||
537 | h->op_tail, | ||
538 | qe); | ||
539 | env = GNUNET_MQ_msg (msg, | ||
540 | GNUNET_MESSAGE_TYPE_NAMECACHE_LOOKUP_BLOCK); | ||
541 | msg->gns_header.r_id = htonl (rid); | ||
542 | msg->query = *derived_hash; | ||
543 | GNUNET_MQ_send (h->mq, | ||
544 | env); | ||
545 | return qe; | ||
546 | } | ||
547 | |||
548 | |||
549 | /** | ||
550 | * Cancel a namecache operation. The final callback from the | ||
551 | * operation must not have been done yet. | ||
552 | * | ||
553 | * @param qe operation to cancel | ||
554 | */ | ||
555 | void | ||
556 | GNUNET_NAMECACHE_cancel (struct GNUNET_NAMECACHE_QueueEntry *qe) | ||
557 | { | ||
558 | struct GNUNET_NAMECACHE_Handle *h = qe->nsh; | ||
559 | |||
560 | GNUNET_CONTAINER_DLL_remove (h->op_head, | ||
561 | h->op_tail, | ||
562 | qe); | ||
563 | GNUNET_free (qe); | ||
564 | } | ||
565 | |||
566 | |||
567 | /* end of namecache_api.c */ | ||