GNUnet  0.10.x
gnunet-service-dht_datacache.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2009, 2010, 2011, 2015, 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 */
26 #include "platform.h"
27 #include "gnunet_datacache_lib.h"
31 #include "gnunet-service-dht.h"
32 
33 #define LOG(kind,...) GNUNET_log_from (kind, "dht-dhtcache",__VA_ARGS__)
34 
39 #define NUM_CLOSEST 42
40 
45 
46 
59 void
61  const struct GNUNET_HashCode *key,
62  unsigned int put_path_length,
63  const struct GNUNET_PeerIdentity *put_path,
65  size_t data_size,
66  const void *data)
67 {
68  int r;
69 
70  if (NULL == datacache)
71  {
73  _("%s request received, but have no datacache!\n"), "PUT");
74  return;
75  }
76  if (data_size >= GNUNET_MAX_MESSAGE_SIZE)
77  {
78  GNUNET_break (0);
79  return;
80  }
81  /* Put size is actual data size plus struct overhead plus path length (if any) */
83  gettext_noop ("# ITEMS stored in datacache"),
84  1,
85  GNUNET_NO);
86  r = GNUNET_DATACACHE_put (datacache,
87  key,
90  data_size,
91  data,
92  type,
93  expiration,
94  put_path_length,
95  put_path);
97  "DATACACHE PUT for key %s [%u] completed (%d) after %u hops\n",
98  GNUNET_h2s (key),
99  data_size,
100  r,
101  put_path_length);
102 }
103 
104 
109 {
113  const void *xquery;
114 
119 
124 
129 
133  void *gc_cls;
134 
138  size_t xquery_size;
139 
144 
145 };
146 
147 
162 static int
164  const struct GNUNET_HashCode *key,
165  size_t data_size,
166  const char *data,
167  enum GNUNET_BLOCK_Type type,
168  struct GNUNET_TIME_Absolute exp,
169  unsigned int put_path_length,
170  const struct GNUNET_PeerIdentity *put_path)
171 {
172  static char non_null;
173  struct GetRequestContext *ctx = cls;
175 
176  if (0 == GNUNET_TIME_absolute_get_remaining (exp).rel_value_us)
177  {
178  GNUNET_break (0); /* why does datacache return expired values? */
179  return GNUNET_OK; /* skip expired record */
180  }
181  if ( (NULL == data) &&
182  (0 == data_size) )
183  data = &non_null; /* point anywhere, but not to NULL */
184 
185  eval
187  type,
188  ctx->bg,
190  key,
191  ctx->xquery,
192  ctx->xquery_size,
193  data,
194  data_size);
196  "Found reply for query %s in datacache, evaluation result is %d\n",
197  GNUNET_h2s (key),
198  (int) eval);
199  ctx->eval = eval;
200  switch (eval)
201  {
204  /* forward to local clients */
207  ("# Good RESULTS found in datacache"), 1,
208  GNUNET_NO);
209  ctx->gc (ctx->gc_cls,
210  type,
211  exp,
212  key,
213  put_path_length, put_path,
214  0, NULL,
215  data, data_size);
216  break;
219  gettext_noop ("# Duplicate RESULTS found in datacache"),
220  1,
221  GNUNET_NO);
222  break;
225  gettext_noop ("# Invalid RESULTS found in datacache"),
226  1,
227  GNUNET_NO);
228  break;
231  gettext_noop ("# Irrelevant RESULTS found in datacache"),
232  1,
233  GNUNET_NO);
234  break;
236  GNUNET_break (0);
237  break;
239  GNUNET_break_op (0);
240  return GNUNET_SYSERR;
243  gettext_noop ("# Unsupported RESULTS found in datacache"),
244  1,
245  GNUNET_NO);
247  _("Unsupported block type (%u) in local response!\n"),
248  type);
249  break;
250  }
252 }
253 
254 
269  enum GNUNET_BLOCK_Type type,
270  const void *xquery,
271  size_t xquery_size,
272  struct GNUNET_BLOCK_Group *bg,
274  void *gc_cls)
275 {
276  struct GetRequestContext ctx;
277  unsigned int r;
278 
279  if (NULL == datacache)
282  gettext_noop ("# GET requests given to datacache"),
283  1,
284  GNUNET_NO);
286  ctx.key = *key;
287  ctx.xquery = xquery;
288  ctx.xquery_size = xquery_size;
289  ctx.bg = bg;
290  ctx.gc = gc;
291  ctx.gc_cls = gc_cls;
292  r = GNUNET_DATACACHE_get (datacache,
293  key,
294  type,
296  &ctx);
298  "DATACACHE GET for key %s completed (%d). %u results found.\n",
299  GNUNET_h2s (key),
300  ctx.eval,
301  r);
302  return ctx.eval;
303 }
304 
305 
320 static int
322  const struct GNUNET_HashCode *key,
323  size_t data_size,
324  const char *data,
325  enum GNUNET_BLOCK_Type type,
326  struct GNUNET_TIME_Absolute exp,
327  unsigned int path_info_len,
328  const struct GNUNET_PeerIdentity *path_info)
329 {
330  struct GNUNET_HashCode *dest = cls;
331 
332  *dest = *key;
333  return GNUNET_OK; /* should actually not matter which we return */
334 }
335 
336 
345 int
347 {
348  if (0 ==
349  GNUNET_DATACACHE_get_random (datacache,
351  key))
352  {
353  /* randomize key in this case */
355  key);
356  return GNUNET_SYSERR;
357  }
358  return GNUNET_OK;
359 }
360 
361 
366 {
371 
375  void *cb_cls;
376 };
377 
378 
393 static int
395  const struct GNUNET_HashCode *key,
396  size_t size,
397  const char *data,
398  enum GNUNET_BLOCK_Type type,
399  struct GNUNET_TIME_Absolute exp,
400  unsigned int put_path_length,
401  const struct GNUNET_PeerIdentity *put_path)
402 {
403  const struct SuccContext *sc = cls;
404 
405  /* NOTE: The datacache currently does not store the RO from
406  the original 'put', so we don't know the 'correct' option
407  at this point anymore. Thus, we conservatively assume
408  that recording is desired (for now). */
409  sc->cb (sc->cb_cls,
411  key,
412  type,
413  put_path_length, put_path,
414  exp,
415  data,
416  size);
417  return GNUNET_OK;
418 }
419 
420 
429 void
432  void *cb_cls)
433 {
434  struct SuccContext sc;
435 
436  sc.cb = cb;
437  sc.cb_cls = cb_cls;
438  (void) GNUNET_DATACACHE_get_closest (datacache,
439  key,
440  NUM_CLOSEST,
442  &sc);
443 }
444 
445 
449 void
451 {
452  datacache = GNUNET_DATACACHE_create (GDS_cfg, "dhtcache");
453 }
454 
455 
459 void
461 {
462  if (NULL != datacache)
463  {
464  GNUNET_DATACACHE_destroy (datacache);
465  datacache = NULL;
466  }
467 }
468 
469 
470 /* end of gnunet-service-dht_datacache.c */
Block does not match query (invalid result)
#define NUM_CLOSEST
How many "closest" results to we return for migration when asked (at most)?
enum GNUNET_BLOCK_EvaluationResult eval
Return value to give back.
GNUnet DHT globals.
struct GNUNET_STATISTICS_Handle * GDS_stats
Handle for the statistics service.
We should keep track of the route that the message took in the P2P network.
size_t xquery_size
Number of bytes in xquery.
static char * expiration
Credential TTL.
void GDS_DATACACHE_init()
Initialize datacache subsystem.
GNUNET_BLOCK_Type
Blocks in the datastore and the datacache must have a unique type.
void(* GDS_DATACACHE_GetCallback)(void *cls, enum GNUNET_BLOCK_Type type, struct GNUNET_TIME_Absolute expiration_time, const struct GNUNET_HashCode *key, unsigned int put_path_length, const struct GNUNET_PeerIdentity *put_path, unsigned int get_path_length, const struct GNUNET_PeerIdentity *get_path, const void *data, size_t data_size)
Handle a result for a GET operation.
unsigned int GNUNET_CRYPTO_hash_matching_bits(const struct GNUNET_HashCode *first, const struct GNUNET_HashCode *second)
Determine how many low order bits match in two struct GNUNET_HashCodes.
Definition: crypto_hash.c:256
void GDS_DATACACHE_done()
Shutdown datacache subsystem.
void GNUNET_DATACACHE_destroy(struct GNUNET_DATACACHE_Handle *h)
Destroy a data cache (and free associated resources).
Definition: datacache.c:232
GDS_DATACACHE_GetCallback gc
Function to call on results.
void(* GDS_DATACACHE_SuccessorCallback)(void *cls, enum GNUNET_DHT_RouteOption options, const struct GNUNET_HashCode *key, enum GNUNET_BLOCK_Type type, unsigned int put_path_length, const struct GNUNET_PeerIdentity *put_path, struct GNUNET_TIME_Absolute expiration, const void *data, size_t data_size)
Send the get result to requesting client.
Block does not match xquery (valid result, not relevant for the request)
int GNUNET_DATACACHE_put(struct GNUNET_DATACACHE_Handle *h, const struct GNUNET_HashCode *key, uint32_t xor_distance, size_t data_size, const char *data, enum GNUNET_BLOCK_Type type, struct GNUNET_TIME_Absolute discard_time, unsigned int path_info_len, const struct GNUNET_PeerIdentity *path_info)
Store an item in the datastore.
Definition: datacache.c:273
#define GNUNET_NO
Definition: gnunet_common.h:81
static int datacache_get_successors_iterator(void *cls, const struct GNUNET_HashCode *key, size_t size, const char *data, enum GNUNET_BLOCK_Type type, struct GNUNET_TIME_Absolute exp, unsigned int put_path_length, const struct GNUNET_PeerIdentity *put_path)
Iterator for local get request results,.
#define GNUNET_OK
Named constants for return values.
Definition: gnunet_common.h:78
const char * GNUNET_h2s(const struct GNUNET_HashCode *hc)
Convert a hash value to a string (for printing debug messages).
void GNUNET_STATISTICS_update(struct GNUNET_STATISTICS_Handle *handle, const char *name, int64_t delta, int make_persistent)
Set statistic value for the peer.
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur...
static struct GNUNET_DNSSTUB_Context * ctx
Context for DNS resolution.
struct GNUNET_HashCode my_identity_hash
Hash of the identity of this peer.
#define _(String)
GNU gettext support macro.
Definition: platform.h:208
struct GNUNET_BLOCK_Context * GDS_block_context
Our handle to the BLOCK library.
struct GNUNET_HashCode key
The key this request was about.
int GDS_DATACACHE_get_random_key(struct GNUNET_HashCode *key)
Obtain a random key from the datacache.
void * cb_cls
Closure for cb.
void GNUNET_CRYPTO_hash_create_random(enum GNUNET_CRYPTO_Quality mode, struct GNUNET_HashCode *result)
Create a random hash code.
Definition: crypto_hash.c:138
#define LOG(kind,...)
Valid result, but suppressed because it is a duplicate.
unsigned int GNUNET_DATACACHE_get(struct GNUNET_DATACACHE_Handle *h, const struct GNUNET_HashCode *key, enum GNUNET_BLOCK_Type type, GNUNET_DATACACHE_Iterator iter, void *iter_cls)
Iterate over the results for a particular key in the datacache.
Definition: datacache.c:338
#define GNUNET_break_op(cond)
Use this for assertion violations caused by other peers (i.e.
enum GNUNET_BLOCK_EvaluationResult GNUNET_BLOCK_evaluate(struct GNUNET_BLOCK_Context *ctx, enum GNUNET_BLOCK_Type type, struct GNUNET_BLOCK_Group *group, enum GNUNET_BLOCK_EvaluationOptions eo, const struct GNUNET_HashCode *query, const void *xquery, size_t xquery_size, const void *reply_block, size_t reply_block_size)
Function called to validate a reply or a request.
Definition: block.c:339
void GDS_DATACACHE_handle_put(struct GNUNET_TIME_Absolute expiration, const struct GNUNET_HashCode *key, unsigned int put_path_length, const struct GNUNET_PeerIdentity *put_path, enum GNUNET_BLOCK_Type type, size_t data_size, const void *data)
Handle a datum we&#39;ve received from another peer.
struct GNUNET_DATACACHE_Handle * GNUNET_DATACACHE_create(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section)
Create a data cache.
Definition: datacache.c:137
Last possible valid result.
Randomness for IVs etc.
GNUnet DHT tracking of requests for routing replies.
A 512-bit hashcode.
Context containing information about a GET request.
struct GNUNET_BLOCK_Group * bg
Block group to use to evaluate replies (updated)
The block is obtained from the local database, skip cryptographic checks.
Valid result, and there may be more.
struct GNUNET_HashCode key
The key used in the DHT.
#define GNUNET_SYSERR
Definition: gnunet_common.h:79
static unsigned int size
Size of the "table".
Definition: peer.c:67
GNUNET_BLOCK_EvaluationResult
Possible ways for how a block may relate to a query.
static struct GNUNET_FS_SearchContext * sc
Definition: gnunet-search.c:37
GNUnet DHT routing code.
#define GNUNET_MAX_MESSAGE_SIZE
Largest supported message (to be precise, one byte more than the largest possible message...
GDS_DATACACHE_SuccessorCallback cb
Function to call on the result.
Specified block type not supported by this plugin.
Closure for datacache_get_successors_iterator().
void GDS_DATACACHE_get_successors(const struct GNUNET_HashCode *key, GDS_DATACACHE_SuccessorCallback cb, void *cb_cls)
Handle a request for data close to a key that we have received from another peer. ...
GNUnet DHT service&#39;s datacache integration.
The identity of the host (wraps the signing key of the peer).
Internal state of the datacache library.
Definition: datacache.c:39
Query format does not match block type (invalid query).
static int datacache_get_iterator(void *cls, const struct GNUNET_HashCode *key, size_t data_size, const char *data, enum GNUNET_BLOCK_Type type, struct GNUNET_TIME_Absolute exp, unsigned int put_path_length, const struct GNUNET_PeerIdentity *put_path)
Iterator for local get request results,.
#define GNUNET_log(kind,...)
Block group data.
void * gc_cls
Closure for gc.
enum GNUNET_BLOCK_EvaluationResult GDS_DATACACHE_handle_get(const struct GNUNET_HashCode *key, enum GNUNET_BLOCK_Type type, const void *xquery, size_t xquery_size, struct GNUNET_BLOCK_Group *bg, GDS_DATACACHE_GetCallback gc, void *gc_cls)
Handle a GET request we&#39;ve received from another peer.
struct GNUNET_TIME_Relative GNUNET_TIME_absolute_get_remaining(struct GNUNET_TIME_Absolute future)
Given a timestamp in the future, how much time remains until then?
Definition: time.c:331
enum GNUNET_TESTBED_UnderlayLinkModelType type
the type of this model
Time for absolute times used by GNUnet, in microseconds.
static int datacache_random_iterator(void *cls, const struct GNUNET_HashCode *key, size_t data_size, const char *data, enum GNUNET_BLOCK_Type type, struct GNUNET_TIME_Absolute exp, unsigned int path_info_len, const struct GNUNET_PeerIdentity *path_info)
Function called with a random element from the datacache.
const struct GNUNET_CONFIGURATION_Handle * GDS_cfg
Configuration we use.
static struct GNUNET_DATACACHE_Handle * datacache
Handle to the datacache service (for inserting/retrieving data)
uint32_t data
The data value.
static size_t data_size
Number of bytes in data.
unsigned int GNUNET_DATACACHE_get_closest(struct GNUNET_DATACACHE_Handle *h, const struct GNUNET_HashCode *key, unsigned int num_results, GNUNET_DATACACHE_Iterator iter, void *iter_cls)
Iterate over the results that are "close" to a particular key in the datacache.
Definition: datacache.c:410
Query is valid, no reply given.
unsigned int GNUNET_DATACACHE_get_random(struct GNUNET_DATACACHE_Handle *h, GNUNET_DATACACHE_Iterator iter, void *iter_cls)
Obtain a random element from the datacache.
Definition: datacache.c:380
const void * xquery
extended query (see gnunet_block_lib.h).
#define gettext_noop(String)
Definition: gettext.h:69