GNUnet  0.11.x
plugin_block_regex.c
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1 /*
2  This file is part of GNUnet
3  Copyright (C) 2013 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 
26 #include "platform.h"
27 #include "gnunet_block_plugin.h"
28 #include "gnunet_block_group_lib.h"
29 #include "block_regex.h"
30 #include "regex_block_lib.h"
31 #include "gnunet_signatures.h"
32 
33 
38 #define BLOOMFILTER_K 16
39 
40 
44 #define REGEX_BF_SIZE 8
45 
46 
59 static struct GNUNET_BLOCK_Group *
62  uint32_t nonce,
63  const void *raw_data,
64  size_t raw_data_size,
65  va_list va)
66 {
67  unsigned int bf_size;
68  const char *guard;
69 
70  guard = va_arg (va, const char *);
71  if (0 == strcmp (guard,
72  "seen-set-size"))
73  bf_size = GNUNET_BLOCK_GROUP_compute_bloomfilter_size (va_arg (va, unsigned
74  int),
76  else if (0 == strcmp (guard,
77  "filter-size"))
78  bf_size = va_arg (va, unsigned int);
79  else
80  {
81  GNUNET_break (0);
82  bf_size = REGEX_BF_SIZE;
83  }
84  GNUNET_break (NULL == va_arg (va, const char *));
85  return GNUNET_BLOCK_GROUP_bf_create (cls,
86  bf_size,
88  type,
89  nonce,
90  raw_data,
91  raw_data_size);
92 }
93 
94 
116  enum GNUNET_BLOCK_Type type,
117  struct GNUNET_BLOCK_Group *bg,
119  const struct GNUNET_HashCode *query,
120  const void *xquery,
121  size_t xquery_size,
122  const void *reply_block,
123  size_t reply_block_size)
124 {
125  struct GNUNET_HashCode chash;
126 
127  if (NULL == reply_block)
128  {
129  if (0 != xquery_size)
130  {
131  const char *s;
132 
133  s = (const char *) xquery;
134  if ('\0' != s[xquery_size - 1]) /* must be valid 0-terminated string */
135  {
136  GNUNET_break_op (0);
138  }
139  }
141  }
142  if (0 != xquery_size)
143  {
144  const char *s;
145 
146  s = (const char *) xquery;
147  if ('\0' != s[xquery_size - 1]) /* must be valid 0-terminated string */
148  {
149  GNUNET_break_op (0);
151  }
152  }
153  else if (NULL != query)
154  {
155  /* xquery is required for regex GETs, at least an empty string */
156  GNUNET_break_op (0);
157  GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "type %d, query %p, xquery %p\n",
158  type, query, xquery);
160  }
161  switch (REGEX_BLOCK_check (reply_block,
162  reply_block_size,
163  query,
164  xquery))
165  {
166  case GNUNET_SYSERR:
167  GNUNET_break_op (0);
169 
170  case GNUNET_NO:
171  /* xquery missmatch, can happen */
173 
174  default:
175  break;
176  }
177  GNUNET_CRYPTO_hash (reply_block,
178  reply_block_size,
179  &chash);
180  if (GNUNET_YES ==
182  &chash))
185 }
186 
187 
209  enum GNUNET_BLOCK_Type type,
210  struct GNUNET_BLOCK_Group *bg,
212  const struct GNUNET_HashCode *query,
213  const void *xquery,
214  size_t xquery_size, const void *reply_block,
215  size_t reply_block_size)
216 {
217  const struct RegexAcceptBlock *rba;
218  struct GNUNET_HashCode chash;
219 
220  if (0 != xquery_size)
221  {
222  GNUNET_break_op (0);
224  }
225  if (NULL == reply_block)
227  if (sizeof(struct RegexAcceptBlock) != reply_block_size)
228  {
229  GNUNET_break_op (0);
231  }
232  rba = reply_block;
233  if (ntohl (rba->purpose.size) !=
234  sizeof(struct GNUNET_CRYPTO_EccSignaturePurpose)
235  + sizeof(struct GNUNET_TIME_AbsoluteNBO)
236  + sizeof(struct GNUNET_HashCode))
237  {
238  GNUNET_break_op (0);
240  }
242  rba->expiration_time)).
243  rel_value_us)
244  {
245  /* technically invalid, but can happen without an error, so
246  we're nice by reporting it as a 'duplicate' */
248  }
249  if (GNUNET_OK !=
251  &rba->purpose,
252  &rba->signature,
253  &rba->peer.public_key))
254  {
255  GNUNET_break_op (0);
257  }
258  GNUNET_CRYPTO_hash (reply_block,
259  reply_block_size,
260  &chash);
261  if (GNUNET_YES ==
263  &chash))
266 }
267 
268 
290  struct GNUNET_BLOCK_Context *ctx,
291  enum GNUNET_BLOCK_Type type,
292  struct GNUNET_BLOCK_Group *bg,
294  const struct GNUNET_HashCode *query,
295  const void *xquery,
296  size_t xquery_size,
297  const void *reply_block,
298  size_t reply_block_size)
299 {
301 
302  switch (type)
303  {
305  result = evaluate_block_regex (cls,
306  type,
307  bg,
308  eo,
309  query,
310  xquery, xquery_size,
311  reply_block, reply_block_size);
312  break;
313 
315  result = evaluate_block_regex_accept (cls,
316  type,
317  bg,
318  eo,
319  query,
320  xquery, xquery_size,
321  reply_block, reply_block_size);
322  break;
323 
324  default:
326  }
327  return result;
328 }
329 
330 
342 static int
344  enum GNUNET_BLOCK_Type type,
345  const void *block,
346  size_t block_size,
347  struct GNUNET_HashCode *key)
348 {
349  switch (type)
350  {
352  if (GNUNET_OK !=
353  REGEX_BLOCK_get_key (block, block_size,
354  key))
355  {
356  GNUNET_break_op (0);
357  return GNUNET_NO;
358  }
359  return GNUNET_OK;
360 
362  if (sizeof(struct RegexAcceptBlock) != block_size)
363  {
364  GNUNET_break_op (0);
365  return GNUNET_NO;
366  }
367  *key = ((struct RegexAcceptBlock *) block)->key;
368  return GNUNET_OK;
369 
370  default:
371  GNUNET_break (0);
372  return GNUNET_SYSERR;
373  }
374 }
375 
376 
380 void *
382 {
383  static enum GNUNET_BLOCK_Type types[] = {
386  GNUNET_BLOCK_TYPE_ANY /* end of list */
387  };
388  struct GNUNET_BLOCK_PluginFunctions *api;
389 
394  api->types = types;
395  return api;
396 }
397 
398 
402 void *
404 {
405  struct GNUNET_BLOCK_PluginFunctions *api = cls;
406 
407  GNUNET_free (api);
408  return NULL;
409 }
410 
411 
412 /* end of plugin_block_regex.c */
Block does not match query (invalid result)
Block to store a cadet regex accepting state.
Handle to an initialized block library.
Definition: block.c:54
struct GNUNET_TIME_Absolute GNUNET_TIME_absolute_ntoh(struct GNUNET_TIME_AbsoluteNBO a)
Convert absolute time from network byte order.
Definition: time.c:673
enum GNUNET_BLOCK_Type * types
0-terminated array of block types supported by this plugin.
static int block_plugin_regex_get_key(void *cls, enum GNUNET_BLOCK_Type type, const void *block, size_t block_size, struct GNUNET_HashCode *key)
Function called to obtain the key for a block.
Any type of block, used as a wildcard when searching.
GNUNET_BLOCK_EvaluationFunction evaluate
Main function of a block plugin.
GNUNET_BLOCK_Type
Blocks in the datastore and the datacache must have a unique type.
int REGEX_BLOCK_get_key(const struct RegexBlock *block, size_t block_len, struct GNUNET_HashCode *key)
Obtain the key that a particular block is to be stored under.
struct GNUNET_CRYPTO_EddsaSignature signature
The signature.
Definition: block_regex.h:75
static struct GNUNET_BLOCK_Group * block_plugin_regex_create_group(void *cls, enum GNUNET_BLOCK_Type type, uint32_t nonce, const void *raw_data, size_t raw_data_size, va_list va)
Create a new block group.
struct GNUNET_BLOCK_Group * GNUNET_BLOCK_GROUP_bf_create(void *cls, size_t bf_size, unsigned int bf_k, enum GNUNET_BLOCK_Type type, uint32_t nonce, const void *raw_data, size_t raw_data_size)
Create a new block group that filters duplicates using a Bloom filter.
Definition: bg_bf.c:174
Each plugin is required to return a pointer to a struct of this type as the return value from its ent...
Block does not match xquery (valid result, not relevant for the request)
#define GNUNET_NO
Definition: gnunet_common.h:78
#define GNUNET_OK
Named constants for return values.
Definition: gnunet_common.h:75
#define GNUNET_new(type)
Allocate a struct or union of the given type.
Block to announce a peer accepting a state.
Definition: block_regex.h:49
size_t GNUNET_BLOCK_GROUP_compute_bloomfilter_size(unsigned int entry_count, unsigned int k)
How many bytes should a bloomfilter be if we have already seen entry_count responses? Sized so that do not have to re-size the filter too often (to keep it cheap).
Definition: bg_bf.c:250
static enum GNUNET_BLOCK_EvaluationResult evaluate_block_regex_accept(void *cls, enum GNUNET_BLOCK_Type type, struct GNUNET_BLOCK_Group *bg, 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 of type GNUNET_BLOCK_TYPE_REGEX_ACCEPT.
Time for absolute time used by GNUnet, in microseconds and in network byte order. ...
#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_PeerIdentity peer
Public key of the peer signing.
Definition: block_regex.h:70
header of what an ECC signature signs this must be followed by "size - 8" bytes of the actual signed ...
int GNUNET_CRYPTO_eddsa_verify(uint32_t purpose, const struct GNUNET_CRYPTO_EccSignaturePurpose *validate, const struct GNUNET_CRYPTO_EddsaSignature *sig, const struct GNUNET_CRYPTO_EddsaPublicKey *pub)
Verify EdDSA signature.
Definition: crypto_ecc.c:1114
Valid result, but suppressed because it is a duplicate.
static enum GNUNET_BLOCK_EvaluationResult block_plugin_regex_evaluate(void *cls, struct GNUNET_BLOCK_Context *ctx, enum GNUNET_BLOCK_Type type, struct GNUNET_BLOCK_Group *bg, 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.
#define GNUNET_break_op(cond)
Use this for assertion violations caused by other peers (i.e.
void GNUNET_CRYPTO_hash(const void *block, size_t size, struct GNUNET_HashCode *ret)
Compute hash of a given block.
Definition: crypto_hash.c:48
static int result
Global testing status.
uint32_t size
How many bytes does this signature sign? (including this purpose header); in network byte order (!)...
struct GNUNET_CRYPTO_EccSignaturePurpose purpose
Accept blocks must be signed.
Definition: block_regex.h:55
A 512-bit hashcode.
Valid result, and there may be more.
struct GNUNET_HashCode key
The key used in the DHT.
#define GNUNET_SYSERR
Definition: gnunet_common.h:76
GNUNET_BLOCK_GroupCreateFunction create_group
Create a block group to process a bunch of blocks in a shared context (i.e.
GNUNET_BLOCK_EvaluationResult
Possible ways for how a block may relate to a query.
static enum GNUNET_BLOCK_EvaluationResult evaluate_block_regex(void *cls, enum GNUNET_BLOCK_Type type, struct GNUNET_BLOCK_Group *bg, 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 of type GNUNET_BLOCK_TYPE_REGEX. ...
Specified block type not supported by this plugin.
void * libgnunet_plugin_block_regex_done(void *cls)
Exit point from the plugin.
GNUNET_BLOCK_GetKeyFunction get_key
Obtain the key for a given block (if possible).
#define GNUNET_SIGNATURE_PURPOSE_REGEX_ACCEPT
Accept state in regex DFA.
Query format does not match block type (invalid query).
common function to manipulate blocks stored by regex in the DHT
#define GNUNET_log(kind,...)
#define BLOOMFILTER_K
Number of bits we set per entry in the bloomfilter.
Block group data.
void * libgnunet_plugin_block_regex_init(void *cls)
Entry point for the plugin.
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
#define GNUNET_YES
Definition: gnunet_common.h:77
#define REGEX_BF_SIZE
How big is the BF we use for REGEX blocks?
int REGEX_BLOCK_check(const struct RegexBlock *block, size_t size, const struct GNUNET_HashCode *query, const char *xquery)
Check if the regex block is well formed, including all edges.
Block to store a cadet regex state.
int GNUNET_BLOCK_GROUP_bf_test_and_set(struct GNUNET_BLOCK_Group *bg, const struct GNUNET_HashCode *hc)
Test if hc is contained in the Bloom filter of bg.
Definition: bg_bf.c:214
void * cls
Closure for all of the callbacks.
GNUNET_BLOCK_EvaluationOptions
Flags that can be set to control the evaluation.
Query is valid, no reply given.
regex block formats
#define GNUNET_free(ptr)
Wrapper around free.
struct GNUNET_CRYPTO_EddsaPublicKey public_key
struct GNUNET_TIME_AbsoluteNBO expiration_time
When does the signature expire?
Definition: block_regex.h:60