diff options
Diffstat (limited to 'src/service/fs/gnunet-service-fs_cadet_server.c')
-rw-r--r-- | src/service/fs/gnunet-service-fs_cadet_server.c | 545 |
1 files changed, 545 insertions, 0 deletions
diff --git a/src/service/fs/gnunet-service-fs_cadet_server.c b/src/service/fs/gnunet-service-fs_cadet_server.c new file mode 100644 index 000000000..8bfe91cf0 --- /dev/null +++ b/src/service/fs/gnunet-service-fs_cadet_server.c | |||
@@ -0,0 +1,545 @@ | |||
1 | /* | ||
2 | This file is part of GNUnet. | ||
3 | Copyright (C) 2012, 2013, 2017 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 fs/gnunet-service-fs_cadet_server.c | ||
23 | * @brief non-anonymous file-transfer | ||
24 | * @author Christian Grothoff | ||
25 | * | ||
26 | * TODO: | ||
27 | * - PORT is set to old application type, unsure if we should keep | ||
28 | * it that way (fine for now) | ||
29 | */ | ||
30 | #include "platform.h" | ||
31 | #include "gnunet_constants.h" | ||
32 | #include "gnunet_util_lib.h" | ||
33 | #include "gnunet_cadet_service.h" | ||
34 | #include "gnunet_protocols.h" | ||
35 | #include "gnunet_applications.h" | ||
36 | #include "gnunet-service-fs.h" | ||
37 | #include "gnunet-service-fs_indexing.h" | ||
38 | #include "gnunet-service-fs_cadet.h" | ||
39 | |||
40 | /** | ||
41 | * After how long do we termiante idle connections? | ||
42 | */ | ||
43 | #define IDLE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 2) | ||
44 | |||
45 | |||
46 | /** | ||
47 | * A message in the queue to be written to the cadet. | ||
48 | */ | ||
49 | struct WriteQueueItem | ||
50 | { | ||
51 | /** | ||
52 | * Kept in a DLL. | ||
53 | */ | ||
54 | struct WriteQueueItem *next; | ||
55 | |||
56 | /** | ||
57 | * Kept in a DLL. | ||
58 | */ | ||
59 | struct WriteQueueItem *prev; | ||
60 | |||
61 | /** | ||
62 | * Number of bytes of payload, allocated at the end of this struct. | ||
63 | */ | ||
64 | size_t msize; | ||
65 | }; | ||
66 | |||
67 | |||
68 | /** | ||
69 | * Information we keep around for each active cadeting client. | ||
70 | */ | ||
71 | struct CadetClient | ||
72 | { | ||
73 | /** | ||
74 | * DLL | ||
75 | */ | ||
76 | struct CadetClient *next; | ||
77 | |||
78 | /** | ||
79 | * DLL | ||
80 | */ | ||
81 | struct CadetClient *prev; | ||
82 | |||
83 | /** | ||
84 | * Channel for communication. | ||
85 | */ | ||
86 | struct GNUNET_CADET_Channel *channel; | ||
87 | |||
88 | /** | ||
89 | * Head of write queue. | ||
90 | */ | ||
91 | struct WriteQueueItem *wqi_head; | ||
92 | |||
93 | /** | ||
94 | * Tail of write queue. | ||
95 | */ | ||
96 | struct WriteQueueItem *wqi_tail; | ||
97 | |||
98 | /** | ||
99 | * Current active request to the datastore, if we have one pending. | ||
100 | */ | ||
101 | struct GNUNET_DATASTORE_QueueEntry *qe; | ||
102 | |||
103 | /** | ||
104 | * Task that is scheduled to asynchronously terminate the connection. | ||
105 | */ | ||
106 | struct GNUNET_SCHEDULER_Task *terminate_task; | ||
107 | |||
108 | /** | ||
109 | * Task that is scheduled to terminate idle connections. | ||
110 | */ | ||
111 | struct GNUNET_SCHEDULER_Task *timeout_task; | ||
112 | |||
113 | /** | ||
114 | * Size of the last write that was initiated. | ||
115 | */ | ||
116 | size_t reply_size; | ||
117 | }; | ||
118 | |||
119 | |||
120 | /** | ||
121 | * Listen port for incoming requests. | ||
122 | */ | ||
123 | static struct GNUNET_CADET_Port *cadet_port; | ||
124 | |||
125 | /** | ||
126 | * Head of DLL of cadet clients. | ||
127 | */ | ||
128 | static struct CadetClient *sc_head; | ||
129 | |||
130 | /** | ||
131 | * Tail of DLL of cadet clients. | ||
132 | */ | ||
133 | static struct CadetClient *sc_tail; | ||
134 | |||
135 | /** | ||
136 | * Number of active cadet clients in the 'sc_*'-DLL. | ||
137 | */ | ||
138 | static unsigned int sc_count; | ||
139 | |||
140 | /** | ||
141 | * Maximum allowed number of cadet clients. | ||
142 | */ | ||
143 | static unsigned long long sc_count_max; | ||
144 | |||
145 | |||
146 | /** | ||
147 | * Task run to asynchronously terminate the cadet due to timeout. | ||
148 | * | ||
149 | * @param cls the 'struct CadetClient' | ||
150 | */ | ||
151 | static void | ||
152 | timeout_cadet_task (void *cls) | ||
153 | { | ||
154 | struct CadetClient *sc = cls; | ||
155 | struct GNUNET_CADET_Channel *tun; | ||
156 | |||
157 | sc->timeout_task = NULL; | ||
158 | tun = sc->channel; | ||
159 | sc->channel = NULL; | ||
160 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
161 | "Timeout for inactive cadet client %p\n", | ||
162 | sc); | ||
163 | GNUNET_CADET_channel_destroy (tun); | ||
164 | } | ||
165 | |||
166 | |||
167 | /** | ||
168 | * Reset the timeout for the cadet client (due to activity). | ||
169 | * | ||
170 | * @param sc client handle to reset timeout for | ||
171 | */ | ||
172 | static void | ||
173 | refresh_timeout_task (struct CadetClient *sc) | ||
174 | { | ||
175 | if (NULL != sc->timeout_task) | ||
176 | GNUNET_SCHEDULER_cancel (sc->timeout_task); | ||
177 | sc->timeout_task = GNUNET_SCHEDULER_add_delayed (IDLE_TIMEOUT, | ||
178 | &timeout_cadet_task, | ||
179 | sc); | ||
180 | } | ||
181 | |||
182 | |||
183 | /** | ||
184 | * Check if we are done with the write queue, and if so tell CADET | ||
185 | * that we are ready to read more. | ||
186 | * | ||
187 | * @param cls where to process the write queue | ||
188 | */ | ||
189 | static void | ||
190 | continue_writing (void *cls) | ||
191 | { | ||
192 | struct CadetClient *sc = cls; | ||
193 | struct GNUNET_MQ_Handle *mq; | ||
194 | |||
195 | mq = GNUNET_CADET_get_mq (sc->channel); | ||
196 | if (0 != GNUNET_MQ_get_length (mq)) | ||
197 | { | ||
198 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
199 | "Write pending, waiting for it to complete\n"); | ||
200 | return; | ||
201 | } | ||
202 | refresh_timeout_task (sc); | ||
203 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
204 | "Finished processing cadet request from client %p, ready to receive the next one\n", | ||
205 | sc); | ||
206 | GNUNET_CADET_receive_done (sc->channel); | ||
207 | } | ||
208 | |||
209 | |||
210 | /** | ||
211 | * Process a datum that was stored in the datastore. | ||
212 | * | ||
213 | * @param cls closure with the `struct CadetClient` which sent the query | ||
214 | * @param key key for the content | ||
215 | * @param size number of bytes in @a data | ||
216 | * @param data content stored | ||
217 | * @param type type of the content | ||
218 | * @param priority priority of the content | ||
219 | * @param anonymity anonymity-level for the content | ||
220 | * @param replication replication-level for the content | ||
221 | * @param expiration expiration time for the content | ||
222 | * @param uid unique identifier for the datum; | ||
223 | * maybe 0 if no unique identifier is available | ||
224 | */ | ||
225 | static void | ||
226 | handle_datastore_reply (void *cls, | ||
227 | const struct GNUNET_HashCode *key, | ||
228 | size_t size, | ||
229 | const void *data, | ||
230 | enum GNUNET_BLOCK_Type type, | ||
231 | uint32_t priority, | ||
232 | uint32_t anonymity, | ||
233 | uint32_t replication, | ||
234 | struct GNUNET_TIME_Absolute expiration, | ||
235 | uint64_t uid) | ||
236 | { | ||
237 | struct CadetClient *sc = cls; | ||
238 | size_t msize = size + sizeof(struct CadetReplyMessage); | ||
239 | struct GNUNET_MQ_Envelope *env; | ||
240 | struct CadetReplyMessage *srm; | ||
241 | |||
242 | sc->qe = NULL; | ||
243 | if (NULL == data) | ||
244 | { | ||
245 | /* no result, this should not really happen, as for | ||
246 | non-anonymous routing only peers that HAVE the | ||
247 | answers should be queried; OTOH, this is not a | ||
248 | hard error as we might have had the answer in the | ||
249 | past and the user might have unindexed it. Hence | ||
250 | we log at level "INFO" for now. */if (NULL == key) | ||
251 | { | ||
252 | GNUNET_log (GNUNET_ERROR_TYPE_INFO, | ||
253 | "Have no answer and the query was NULL\n"); | ||
254 | } | ||
255 | else | ||
256 | { | ||
257 | GNUNET_log (GNUNET_ERROR_TYPE_INFO, | ||
258 | "Have no answer for query `%s'\n", | ||
259 | GNUNET_h2s (key)); | ||
260 | } | ||
261 | GNUNET_STATISTICS_update (GSF_stats, | ||
262 | gettext_noop ( | ||
263 | "# queries received via CADET not answered"), | ||
264 | 1, | ||
265 | GNUNET_NO); | ||
266 | continue_writing (sc); | ||
267 | return; | ||
268 | } | ||
269 | if (GNUNET_BLOCK_TYPE_FS_ONDEMAND == type) | ||
270 | { | ||
271 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
272 | "Performing on-demand encoding for query %s\n", | ||
273 | GNUNET_h2s (key)); | ||
274 | if (GNUNET_OK != | ||
275 | GNUNET_FS_handle_on_demand_block (key, | ||
276 | size, | ||
277 | data, | ||
278 | type, | ||
279 | priority, | ||
280 | anonymity, | ||
281 | replication, | ||
282 | expiration, | ||
283 | uid, | ||
284 | &handle_datastore_reply, | ||
285 | sc)) | ||
286 | { | ||
287 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
288 | "On-demand encoding request failed\n"); | ||
289 | continue_writing (sc); | ||
290 | } | ||
291 | return; | ||
292 | } | ||
293 | if (msize > GNUNET_MAX_MESSAGE_SIZE) | ||
294 | { | ||
295 | GNUNET_break (0); | ||
296 | continue_writing (sc); | ||
297 | return; | ||
298 | } | ||
299 | GNUNET_break (GNUNET_BLOCK_TYPE_ANY != type); | ||
300 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
301 | "Starting transmission of %u byte reply of type %d for query `%s' via cadet to %p\n", | ||
302 | (unsigned int) size, | ||
303 | (unsigned int) type, | ||
304 | GNUNET_h2s (key), | ||
305 | sc); | ||
306 | env = GNUNET_MQ_msg_extra (srm, | ||
307 | size, | ||
308 | GNUNET_MESSAGE_TYPE_FS_CADET_REPLY); | ||
309 | srm->type = htonl (type); | ||
310 | srm->expiration = GNUNET_TIME_absolute_hton (expiration); | ||
311 | GNUNET_memcpy (&srm[1], | ||
312 | data, | ||
313 | size); | ||
314 | GNUNET_MQ_notify_sent (env, | ||
315 | &continue_writing, | ||
316 | sc); | ||
317 | GNUNET_STATISTICS_update (GSF_stats, | ||
318 | gettext_noop ("# Blocks transferred via cadet"), | ||
319 | 1, | ||
320 | GNUNET_NO); | ||
321 | GNUNET_MQ_send (GNUNET_CADET_get_mq (sc->channel), | ||
322 | env); | ||
323 | } | ||
324 | |||
325 | |||
326 | /** | ||
327 | * Functions with this signature are called whenever a | ||
328 | * complete query message is received. | ||
329 | * | ||
330 | * @param cls closure with the `struct CadetClient` | ||
331 | * @param sqm the actual message | ||
332 | */ | ||
333 | static void | ||
334 | handle_request (void *cls, | ||
335 | const struct CadetQueryMessage *sqm) | ||
336 | { | ||
337 | struct CadetClient *sc = cls; | ||
338 | |||
339 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
340 | "Received query for `%s' via cadet from client %p\n", | ||
341 | GNUNET_h2s (&sqm->query), | ||
342 | sc); | ||
343 | GNUNET_STATISTICS_update (GSF_stats, | ||
344 | gettext_noop ("# queries received via cadet"), | ||
345 | 1, | ||
346 | GNUNET_NO); | ||
347 | refresh_timeout_task (sc); | ||
348 | sc->qe = GNUNET_DATASTORE_get_key (GSF_dsh, | ||
349 | 0 /* next_uid */, | ||
350 | false /* random */, | ||
351 | &sqm->query, | ||
352 | ntohl (sqm->type), | ||
353 | 0 /* priority */, | ||
354 | GSF_datastore_queue_size, | ||
355 | &handle_datastore_reply, | ||
356 | sc); | ||
357 | if (NULL == sc->qe) | ||
358 | { | ||
359 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
360 | "Queueing request with datastore failed (queue full?)\n"); | ||
361 | continue_writing (sc); | ||
362 | } | ||
363 | } | ||
364 | |||
365 | |||
366 | /** | ||
367 | * Functions of this type are called upon new cadet connection from other peers. | ||
368 | * | ||
369 | * @param cls the closure from GNUNET_CADET_connect | ||
370 | * @param channel the channel representing the cadet | ||
371 | * @param initiator the identity of the peer who wants to establish a cadet | ||
372 | * with us; NULL on binding error | ||
373 | * @return initial channel context (our `struct CadetClient`) | ||
374 | */ | ||
375 | static void * | ||
376 | connect_cb (void *cls, | ||
377 | struct GNUNET_CADET_Channel *channel, | ||
378 | const struct GNUNET_PeerIdentity *initiator) | ||
379 | { | ||
380 | struct CadetClient *sc; | ||
381 | |||
382 | GNUNET_assert (NULL != channel); | ||
383 | if (sc_count >= sc_count_max) | ||
384 | { | ||
385 | GNUNET_STATISTICS_update (GSF_stats, | ||
386 | gettext_noop ( | ||
387 | "# cadet client connections rejected"), | ||
388 | 1, | ||
389 | GNUNET_NO); | ||
390 | GNUNET_CADET_channel_destroy (channel); | ||
391 | return NULL; | ||
392 | } | ||
393 | GNUNET_STATISTICS_update (GSF_stats, | ||
394 | gettext_noop ("# cadet connections active"), | ||
395 | 1, | ||
396 | GNUNET_NO); | ||
397 | sc = GNUNET_new (struct CadetClient); | ||
398 | sc->channel = channel; | ||
399 | GNUNET_CONTAINER_DLL_insert (sc_head, | ||
400 | sc_tail, | ||
401 | sc); | ||
402 | sc_count++; | ||
403 | refresh_timeout_task (sc); | ||
404 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
405 | "Accepting inbound cadet connection from `%s' as client %p\n", | ||
406 | GNUNET_i2s (initiator), | ||
407 | sc); | ||
408 | return sc; | ||
409 | } | ||
410 | |||
411 | |||
412 | /** | ||
413 | * Function called by cadet when a client disconnects. | ||
414 | * Cleans up our `struct CadetClient` of that channel. | ||
415 | * | ||
416 | * @param cls our `struct CadetClient` | ||
417 | * @param channel channel of the disconnecting client | ||
418 | */ | ||
419 | static void | ||
420 | disconnect_cb (void *cls, | ||
421 | const struct GNUNET_CADET_Channel *channel) | ||
422 | { | ||
423 | struct CadetClient *sc = cls; | ||
424 | struct WriteQueueItem *wqi; | ||
425 | |||
426 | if (NULL == sc) | ||
427 | return; | ||
428 | sc->channel = NULL; | ||
429 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
430 | "Terminating cadet connection with client %p\n", | ||
431 | sc); | ||
432 | GNUNET_STATISTICS_update (GSF_stats, | ||
433 | gettext_noop ("# cadet connections active"), -1, | ||
434 | GNUNET_NO); | ||
435 | if (NULL != sc->terminate_task) | ||
436 | GNUNET_SCHEDULER_cancel (sc->terminate_task); | ||
437 | if (NULL != sc->timeout_task) | ||
438 | GNUNET_SCHEDULER_cancel (sc->timeout_task); | ||
439 | if (NULL != sc->qe) | ||
440 | GNUNET_DATASTORE_cancel (sc->qe); | ||
441 | while (NULL != (wqi = sc->wqi_head)) | ||
442 | { | ||
443 | GNUNET_CONTAINER_DLL_remove (sc->wqi_head, | ||
444 | sc->wqi_tail, | ||
445 | wqi); | ||
446 | GNUNET_free (wqi); | ||
447 | } | ||
448 | GNUNET_CONTAINER_DLL_remove (sc_head, | ||
449 | sc_tail, | ||
450 | sc); | ||
451 | sc_count--; | ||
452 | GNUNET_free (sc); | ||
453 | } | ||
454 | |||
455 | |||
456 | /** | ||
457 | * Function called whenever an MQ-channel's transmission window size changes. | ||
458 | * | ||
459 | * The first callback in an outgoing channel will be with a non-zero value | ||
460 | * and will mean the channel is connected to the destination. | ||
461 | * | ||
462 | * For an incoming channel it will be called immediately after the | ||
463 | * #GNUNET_CADET_ConnectEventHandler, also with a non-zero value. | ||
464 | * | ||
465 | * @param cls Channel closure. | ||
466 | * @param channel Connection to the other end (henceforth invalid). | ||
467 | * @param window_size New window size. If the is more messages than buffer size | ||
468 | * this value will be negative.. | ||
469 | */ | ||
470 | static void | ||
471 | window_change_cb (void *cls, | ||
472 | const struct GNUNET_CADET_Channel *channel, | ||
473 | int window_size) | ||
474 | { | ||
475 | /* FIXME: could do flow control here... */ | ||
476 | } | ||
477 | |||
478 | |||
479 | /** | ||
480 | * Initialize subsystem for non-anonymous file-sharing. | ||
481 | */ | ||
482 | void | ||
483 | GSF_cadet_start_server () | ||
484 | { | ||
485 | struct GNUNET_MQ_MessageHandler handlers[] = { | ||
486 | GNUNET_MQ_hd_fixed_size (request, | ||
487 | GNUNET_MESSAGE_TYPE_FS_CADET_QUERY, | ||
488 | struct CadetQueryMessage, | ||
489 | NULL), | ||
490 | GNUNET_MQ_handler_end () | ||
491 | }; | ||
492 | struct GNUNET_HashCode port; | ||
493 | |||
494 | if (GNUNET_YES != | ||
495 | GNUNET_CONFIGURATION_get_value_number (GSF_cfg, | ||
496 | "fs", | ||
497 | "MAX_CADET_CLIENTS", | ||
498 | &sc_count_max)) | ||
499 | return; | ||
500 | GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, | ||
501 | "Initializing cadet FS server with a limit of %llu connections\n", | ||
502 | sc_count_max); | ||
503 | cadet_map = GNUNET_CONTAINER_multipeermap_create (16, GNUNET_YES); | ||
504 | cadet_handle = GNUNET_CADET_connect (GSF_cfg); | ||
505 | GNUNET_assert (NULL != cadet_handle); | ||
506 | GNUNET_CRYPTO_hash (GNUNET_APPLICATION_PORT_FS_BLOCK_TRANSFER, | ||
507 | strlen (GNUNET_APPLICATION_PORT_FS_BLOCK_TRANSFER), | ||
508 | &port); | ||
509 | cadet_port = GNUNET_CADET_open_port (cadet_handle, | ||
510 | &port, | ||
511 | &connect_cb, | ||
512 | NULL, | ||
513 | &window_change_cb, | ||
514 | &disconnect_cb, | ||
515 | handlers); | ||
516 | } | ||
517 | |||
518 | |||
519 | /** | ||
520 | * Shutdown subsystem for non-anonymous file-sharing. | ||
521 | */ | ||
522 | void | ||
523 | GSF_cadet_stop_server () | ||
524 | { | ||
525 | GNUNET_CONTAINER_multipeermap_iterate (cadet_map, | ||
526 | &GSF_cadet_release_clients, | ||
527 | NULL); | ||
528 | GNUNET_CONTAINER_multipeermap_destroy (cadet_map); | ||
529 | cadet_map = NULL; | ||
530 | if (NULL != cadet_port) | ||
531 | { | ||
532 | GNUNET_CADET_close_port (cadet_port); | ||
533 | cadet_port = NULL; | ||
534 | } | ||
535 | if (NULL != cadet_handle) | ||
536 | { | ||
537 | GNUNET_CADET_disconnect (cadet_handle); | ||
538 | cadet_handle = NULL; | ||
539 | } | ||
540 | GNUNET_assert (NULL == sc_head); | ||
541 | GNUNET_assert (0 == sc_count); | ||
542 | } | ||
543 | |||
544 | |||
545 | /* end of gnunet-service-fs_cadet.c */ | ||