GNUnet 0.22.2
namecache_api.c
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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
29#include "platform.h"
30#include "gnunet_util_lib.h"
31#include "gnunet_constants.h"
33#include "gnunet_signatures.h"
35#include "namecache.h"
36
37
38#define LOG(kind, ...) GNUNET_log_from (kind, "namecache-api", __VA_ARGS__)
39
40
46{
51
56
61
66
70 void *cont_cls;
71
76
81
85 uint32_t op_id;
86};
87
88
93{
98
103
107 struct GNUNET_CLIENT_TransmitHandle *th;
108
113
118
123
128
133
138};
139
140
146static void
148
149
157static struct GNUNET_NAMECACHE_QueueEntry *
159 uint32_t rid)
160{
162
163 for (qe = h->op_head; qe != NULL; qe = qe->next)
164 {
165 if (qe->op_id == rid)
166 {
168 h->op_tail,
169 qe);
170 return qe;
171 }
172 }
173 return NULL;
174}
175
176
184static int
186 const struct LookupBlockResponseMessage *msg)
187{
188 /* any length will do, format validation is in handler */
189 return GNUNET_OK;
190}
191
192
200static void
202 const struct LookupBlockResponseMessage *msg)
203{
204 struct GNUNET_NAMECACHE_Handle *h = cls;
205 size_t size;
207
209 "Received LOOKUP_BLOCK_RESPONSE\n");
210 qe = find_qe (h,
211 ntohl (msg->gns_header.r_id));
212 if (NULL == qe)
213 return;
214 if (0 == GNUNET_TIME_absolute_ntoh (msg->expire).abs_value_us)
215 {
216 /* no match found */
217 if (NULL != qe->block_proc)
218 qe->block_proc (qe->block_proc_cls,
219 NULL);
220 GNUNET_free (qe);
221 return;
222 }
223 size = ntohs (msg->gns_header.header.size)
224 - sizeof(struct LookupBlockResponseMessage);
225 {
226 char buf[size] GNUNET_ALIGN;
227 struct GNUNET_GNSRECORD_Block *block;
228
229 memset (buf, 0, size);
230 block = (struct GNUNET_GNSRECORD_Block *) buf;
231 GNUNET_memcpy (block,
232 &msg[1],
233 size);
234 if (GNUNET_OK !=
236 {
237 GNUNET_break (0);
238 if (NULL != qe->block_proc)
239 qe->block_proc (qe->block_proc_cls,
240 NULL);
242 }
243 else
244 {
245 if (NULL != qe->block_proc)
246 qe->block_proc (qe->block_proc_cls,
247 block);
248 }
249 }
250 GNUNET_free (qe);
251}
252
253
262static void
264 const struct BlockCacheResponseMessage *msg)
265{
266 struct GNUNET_NAMECACHE_Handle *h = cls;
268 int res;
269
271 "Received BLOCK_CACHE_RESPONSE\n");
272 qe = find_qe (h,
273 ntohl (msg->gns_header.r_id));
274 if (NULL == qe)
275 return;
276 res = ntohl (msg->op_result);
277 /* TODO: add actual error message from namecache to response... */
278 if (NULL != qe->cont)
279 qe->cont (qe->cont_cls,
280 res,
281 (GNUNET_OK == res)
282 ? NULL
283 : _ ("Namecache failed to cache block"));
284 GNUNET_free (qe);
285}
286
287
296static void
298 enum GNUNET_MQ_Error error)
299{
300 struct GNUNET_NAMECACHE_Handle *h = cls;
301
303}
304
305
311static void
313{
315 GNUNET_MQ_hd_var_size (lookup_block_response,
318 h),
319 GNUNET_MQ_hd_fixed_size (block_cache_response,
322 h),
324 };
325
326 GNUNET_assert (NULL == h->mq);
328 "namecache",
329 handlers,
331 h);
332}
333
334
340static void
342{
343 struct GNUNET_NAMECACHE_Handle *h = cls;
344
345 h->reconnect_task = NULL;
346 reconnect (h);
347}
348
349
355static void
357{
359
360 h->reconnect = GNUNET_NO;
362 h->mq = NULL;
363 while (NULL != (qe = h->op_head))
364 {
366 h->op_tail,
367 qe);
368 if (NULL != qe->cont)
369 qe->cont (qe->cont_cls,
371 _ ("Error communicating with namecache service"));
372 GNUNET_free (qe);
373 }
375 "Reconnecting to namecache\n");
376 h->reconnect_delay = GNUNET_TIME_STD_BACKOFF (h->reconnect_delay);
377 h->reconnect_task = GNUNET_SCHEDULER_add_delayed (h->reconnect_delay,
379 h);
380}
381
382
389static uint32_t
391{
392 return h->last_op_id_used++;
393}
394
395
404{
406
408 h->cfg = cfg;
409 reconnect (h);
410 if (NULL == h->mq)
411 {
412 GNUNET_free (h);
413 return NULL;
414 }
415 return h;
416}
417
418
425void
427{
429
430 GNUNET_break (NULL == h->op_head);
431 while (NULL != (q = h->op_head))
432 {
434 h->op_tail,
435 q);
436 GNUNET_free (q);
437 }
438 if (NULL != h->mq)
439 {
441 h->mq = NULL;
442 }
443 if (NULL != h->reconnect_task)
444 {
446 h->reconnect_task = NULL;
447 }
448 GNUNET_free (h);
449}
450
451
464 const struct GNUNET_GNSRECORD_Block *block,
466 void *cont_cls)
467{
469 struct BlockCacheMessage *msg;
470 struct GNUNET_MQ_Envelope *env;
471 uint32_t rid;
472 size_t blen;
473
474 if (NULL == h->mq)
475 return NULL;
476 blen = GNUNET_GNSRECORD_block_get_size (block);
477 rid = get_op_id (h);
479 qe->nsh = h;
480 qe->cont = cont;
481 qe->cont_cls = cont_cls;
482 qe->op_id = rid;
484 h->op_tail,
485 qe);
486 /* send msg */
488 blen,
490 msg->gns_header.r_id = htonl (rid);
491 GNUNET_memcpy (&msg[1],
492 block,
493 blen);
495 env);
496 return qe;
497}
498
499
513 const struct GNUNET_HashCode *derived_hash,
515 void *proc_cls)
516{
518 struct LookupBlockMessage *msg;
519 struct GNUNET_MQ_Envelope *env;
520 uint32_t rid;
521
522 if (NULL == h->mq)
523 return NULL;
525 "Looking for block under %s\n",
526 GNUNET_h2s (derived_hash));
527 rid = get_op_id (h);
529 qe->nsh = h;
530 qe->block_proc = proc;
531 qe->block_proc_cls = proc_cls;
532 qe->op_id = rid;
534 h->op_tail,
535 qe);
538 msg->gns_header.r_id = htonl (rid);
539 msg->query = *derived_hash;
541 env);
542 return qe;
543}
544
545
552void
554{
555 struct GNUNET_NAMECACHE_Handle *h = qe->nsh;
556
558 h->op_tail,
559 qe);
560 GNUNET_free (qe);
561}
562
563
564/* end of namecache_api.c */
struct GNUNET_MQ_MessageHandlers handlers[]
Definition: 003.c:1
struct GNUNET_MessageHeader * msg
Definition: 005.c:2
struct GNUNET_MQ_Envelope * env
Definition: 005.c:1
static struct GNUNET_ARM_Handle * h
Connection with ARM.
Definition: gnunet-arm.c:98
static struct GNUNET_CONFIGURATION_Handle * cfg
Our configuration.
Definition: gnunet-arm.c:108
static struct GNUNET_DATASTORE_QueueEntry * qe
Current operation.
static char * res
Currently read line or NULL on EOF.
static struct GNUNET_REVOCATION_Query * q
Handle for revocation query.
API that can be used to manipulate GNS record data.
API that can be used to store naming information on a GNUnet node.
struct GNUNET_MQ_Handle * GNUNET_CLIENT_connect(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *service_name, const struct GNUNET_MQ_MessageHandler *handlers, GNUNET_MQ_ErrorHandler error_handler, void *error_handler_cls)
Create a message queue to connect to a GNUnet service.
Definition: client.c:1060
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
#define GNUNET_CONTAINER_DLL_insert_tail(head, tail, element)
Insert an element at the tail of a DLL.
enum GNUNET_GenericReturnValue GNUNET_GNSRECORD_block_verify(const struct GNUNET_GNSRECORD_Block *block)
Check if a signature is valid.
size_t GNUNET_GNSRECORD_block_get_size(const struct GNUNET_GNSRECORD_Block *block)
Returns the length of this block in bytes.
#define GNUNET_log(kind,...)
void * cls
Closure for mv and cb.
#define GNUNET_ALIGN
gcc-ism to force alignment; we use this to align char-arrays that may then be cast to 'struct's.
#define GNUNET_memcpy(dst, src, n)
Call memcpy() but check for n being 0 first.
uint16_t size
The length of the struct (in bytes, including the length field itself), in big-endian format.
@ GNUNET_OK
@ GNUNET_NO
@ GNUNET_SYSERR
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur.
const char * GNUNET_h2s(const struct GNUNET_HashCode *hc)
Convert a hash value to a string (for printing debug messages).
@ GNUNET_ERROR_TYPE_DEBUG
#define GNUNET_new(type)
Allocate a struct or union of the given type.
#define GNUNET_free(ptr)
Wrapper around free.
GNUNET_MQ_Error
Error codes for the queue.
void GNUNET_MQ_send(struct GNUNET_MQ_Handle *mq, struct GNUNET_MQ_Envelope *ev)
Send a message with the given message queue.
Definition: mq.c:305
#define GNUNET_MQ_handler_end()
End-marker for the handlers array.
#define GNUNET_MQ_msg_extra(mvar, esize, type)
Allocate an envelope, with extra space allocated after the space needed by the message struct.
Definition: gnunet_mq_lib.h:63
#define GNUNET_MQ_msg(mvar, type)
Allocate a GNUNET_MQ_Envelope.
Definition: gnunet_mq_lib.h:78
#define GNUNET_MQ_hd_var_size(name, code, str, ctx)
#define GNUNET_MQ_hd_fixed_size(name, code, str, ctx)
void GNUNET_MQ_destroy(struct GNUNET_MQ_Handle *mq)
Destroy the message queue.
Definition: mq.c:700
struct GNUNET_NAMECACHE_Handle * GNUNET_NAMECACHE_connect(const struct GNUNET_CONFIGURATION_Handle *cfg)
Initialize the connection with the NAMECACHE service.
void(* GNUNET_NAMECACHE_ContinuationWithStatus)(void *cls, int32_t success, const char *emsg)
Continuation called to notify client about result of the operation.
void GNUNET_NAMECACHE_disconnect(struct GNUNET_NAMECACHE_Handle *h)
Disconnect from the namecache service (and free associated resources).
void GNUNET_NAMECACHE_cancel(struct GNUNET_NAMECACHE_QueueEntry *qe)
Cancel a namecache operation.
void(* GNUNET_NAMECACHE_BlockProcessor)(void *cls, const struct GNUNET_GNSRECORD_Block *block)
Process a record that was stored in the namecache.
struct GNUNET_NAMECACHE_QueueEntry * GNUNET_NAMECACHE_lookup_block(struct GNUNET_NAMECACHE_Handle *h, const struct GNUNET_HashCode *derived_hash, GNUNET_NAMECACHE_BlockProcessor proc, void *proc_cls)
Get a result for a particular key from the namecache.
struct GNUNET_NAMECACHE_QueueEntry * GNUNET_NAMECACHE_block_cache(struct GNUNET_NAMECACHE_Handle *h, const struct GNUNET_GNSRECORD_Block *block, GNUNET_NAMECACHE_ContinuationWithStatus cont, void *cont_cls)
Store an item in the namecache.
#define GNUNET_MESSAGE_TYPE_NAMECACHE_LOOKUP_BLOCK
Client to service: lookup block.
#define GNUNET_MESSAGE_TYPE_NAMECACHE_BLOCK_CACHE_RESPONSE
Service to client: result of block cache request.
#define GNUNET_MESSAGE_TYPE_NAMECACHE_BLOCK_CACHE
Client to service: cache a block.
#define GNUNET_MESSAGE_TYPE_NAMECACHE_LOOKUP_BLOCK_RESPONSE
Service to client: result of block lookup.
void * GNUNET_SCHEDULER_cancel(struct GNUNET_SCHEDULER_Task *task)
Cancel the task with the specified identifier.
Definition: scheduler.c:979
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_delayed(struct GNUNET_TIME_Relative delay, GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run with a specified delay.
Definition: scheduler.c:1276
struct GNUNET_TIME_Absolute GNUNET_TIME_absolute_ntoh(struct GNUNET_TIME_AbsoluteNBO a)
Convert absolute time from network byte order.
Definition: time.c:741
#define GNUNET_TIME_STD_BACKOFF(r)
Perform our standard exponential back-off calculation, starting at 1 ms and then going by a factor of...
common internal definitions for namecache service
static uint32_t get_op_id(struct GNUNET_NAMECACHE_Handle *h)
Get a fresh operation id to distinguish between namecache requests.
static void handle_lookup_block_response(void *cls, const struct LookupBlockResponseMessage *msg)
Handle an incoming message of type GNUNET_MESSAGE_TYPE_NAMECACHE_LOOKUP_BLOCK_RESPONSE.
static void reconnect(struct GNUNET_NAMECACHE_Handle *h)
Reconnect to namecache service.
static int check_lookup_block_response(void *cls, const struct LookupBlockResponseMessage *msg)
Handle an incoming message of type GNUNET_MESSAGE_TYPE_NAMECACHE_LOOKUP_BLOCK_RESPONSE.
static struct GNUNET_NAMECACHE_QueueEntry * find_qe(struct GNUNET_NAMECACHE_Handle *h, uint32_t rid)
Find queue entry for the given rid.
static void mq_error_handler(void *cls, enum GNUNET_MQ_Error error)
Generic error handler, called with the appropriate error code and the same closure specified at the c...
static void force_reconnect(struct GNUNET_NAMECACHE_Handle *h)
Disconnect from service and then reconnect.
#define LOG(kind,...)
Definition: namecache_api.c:38
static void handle_block_cache_response(void *cls, const struct BlockCacheResponseMessage *msg)
Handle an incoming message of type GNUNET_MESSAGE_TYPE_NAMECACHE_BLOCK_CACHE_RESPONSE.
static void reconnect_task(void *cls)
Re-establish the connection to the service.
static unsigned int size
Size of the "table".
Definition: peer.c:68
#define _(String)
GNU gettext support macro.
Definition: platform.h:178
Cache a record in the namecache.
Definition: namecache.h:95
Response to a request to cache a block.
Definition: namecache.h:114
struct GNUNET_MQ_Handle * mq
Our connection to the ARM service.
Definition: arm_api.c:107
const struct GNUNET_CONFIGURATION_Handle * cfg
The configuration that we are using.
Definition: arm_api.c:112
struct GNUNET_SCHEDULER_Task * reconnect_task
ID of the reconnect task (if any).
Definition: arm_api.c:147
struct GNUNET_DATASTORE_QueueEntry * next
This is a linked list.
GNUNET_DATASTORE_ContinuationWithStatus cont
Function to call after transmission of the request.
void * cont_cls
Closure for cont.
A 512-bit hashcode.
Handle to a message queue.
Definition: mq.c:87
Message handler for a specific message type.
Connection to the NAMECACHE service.
Definition: namecache_api.c:93
struct GNUNET_CLIENT_TransmitHandle * th
Currently pending transmission request (or NULL).
struct GNUNET_TIME_Relative reconnect_delay
Delay introduced before we reconnect.
struct GNUNET_MQ_Handle * mq
Message queue to service.
const struct GNUNET_CONFIGURATION_Handle * cfg
Configuration to use.
Definition: namecache_api.c:97
uint32_t last_op_id_used
The last operation id used for a NAMECACHE operation.
struct GNUNET_NAMECACHE_QueueEntry * op_head
Head of pending namecache queue entries.
int reconnect
Should we reconnect to service due to some serious error?
struct GNUNET_SCHEDULER_Task * reconnect_task
Reconnect task.
struct GNUNET_NAMECACHE_QueueEntry * op_tail
Tail of pending namecache queue entries.
An QueueEntry used to store information for a pending NAMECACHE record operation.
Definition: namecache_api.c:46
struct GNUNET_NAMECACHE_QueueEntry * prev
Kept in a DLL.
Definition: namecache_api.c:55
void * cont_cls
Closure for cont.
Definition: namecache_api.c:70
struct GNUNET_NAMECACHE_QueueEntry * next
Kept in a DLL.
Definition: namecache_api.c:50
GNUNET_NAMECACHE_ContinuationWithStatus cont
Continuation to call.
Definition: namecache_api.c:65
GNUNET_NAMECACHE_BlockProcessor block_proc
Function to call with the blocks we get back; or NULL.
Definition: namecache_api.c:75
struct GNUNET_NAMECACHE_Handle * nsh
Main handle to access the namecache.
Definition: namecache_api.c:60
uint32_t op_id
The operation id this zone iteration operation has.
Definition: namecache_api.c:85
void * block_proc_cls
Closure for block_proc.
Definition: namecache_api.c:80
Entry in list of pending tasks.
Definition: scheduler.c:135
uint64_t abs_value_us
The actual value.
Time for relative time used by GNUnet, in microseconds.
Lookup a block in the namecache.
Definition: namecache.h:59
Lookup response.
Definition: namecache.h:76