GNUnet  0.10.x
plugin_block_gns.c
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1 /*
2  This file is part of GNUnet
3  Copyright (C) 2010-2013 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 
28 #include "platform.h"
29 #include "gnunet_block_group_lib.h"
30 #include "gnunet_block_plugin.h"
32 #include "gnunet_signatures.h"
33 
38 #define BLOOMFILTER_K 16
39 
43 #define GNS_BF_SIZE 8
44 
45 
58 static struct GNUNET_BLOCK_Group *
61  uint32_t nonce,
62  const void *raw_data,
63  size_t raw_data_size,
64  va_list va)
65 {
66  unsigned int bf_size;
67  const char *guard;
68 
69  guard = va_arg(va, const char *);
70  if (0 == strcmp(guard,
71  "seen-set-size"))
72  bf_size = GNUNET_BLOCK_GROUP_compute_bloomfilter_size(va_arg(va, unsigned int),
74  else if (0 == strcmp(guard,
75  "filter-size"))
76  bf_size = va_arg(va, unsigned int);
77  else
78  {
79  GNUNET_break(0);
80  bf_size = GNS_BF_SIZE;
81  }
82  GNUNET_break(NULL == va_arg(va, const char *));
84  bf_size,
86  type,
87  nonce,
88  raw_data,
89  raw_data_size);
90 }
91 
92 
114  struct GNUNET_BLOCK_Context *ctx,
115  enum GNUNET_BLOCK_Type type,
116  struct GNUNET_BLOCK_Group *bg,
118  const struct GNUNET_HashCode *query,
119  const void *xquery,
120  size_t xquery_size,
121  const void *reply_block,
122  size_t reply_block_size)
123 {
124  const struct GNUNET_GNSRECORD_Block *block;
125  struct GNUNET_HashCode h;
126  struct GNUNET_HashCode chash;
127 
130  if (NULL == reply_block)
131  {
132  if (0 != xquery_size)
133  {
134  GNUNET_break_op(0);
136  }
138  }
139 
140  /* this is a reply */
141  if (reply_block_size < sizeof(struct GNUNET_GNSRECORD_Block))
142  {
143  GNUNET_break_op(0);
145  }
146  block = reply_block;
147  if (ntohl(block->purpose.size) + sizeof(struct GNUNET_CRYPTO_EcdsaSignature) + sizeof(struct GNUNET_CRYPTO_EcdsaPublicKey) !=
148  reply_block_size)
149  {
150  GNUNET_break_op(0);
152  }
154  sizeof(block->derived_key),
155  &h);
156  if (0 != GNUNET_memcmp(&h, query))
157  {
158  GNUNET_break_op(0);
160  }
161  if (GNUNET_OK !=
163  {
164  GNUNET_break_op(0);
166  }
167  GNUNET_CRYPTO_hash(reply_block,
168  reply_block_size,
169  &chash);
170  if (GNUNET_YES ==
172  &chash))
175 }
176 
177 
189 static int
191  enum GNUNET_BLOCK_Type type,
192  const void *reply_block,
193  size_t reply_block_size,
194  struct GNUNET_HashCode *key)
195 {
196  const struct GNUNET_GNSRECORD_Block *block;
197 
199  return GNUNET_SYSERR;
200  if (reply_block_size < sizeof(struct GNUNET_GNSRECORD_Block))
201  {
202  GNUNET_break_op(0);
204  }
205  block = reply_block;
207  sizeof(block->derived_key),
208  key);
209  return GNUNET_OK;
210 }
211 
212 
216 void *
218 {
219  static enum GNUNET_BLOCK_Type types[] =
220  {
222  GNUNET_BLOCK_TYPE_ANY /* end of list */
223  };
224  struct GNUNET_BLOCK_PluginFunctions *api;
225 
230  api->types = types;
231  return api;
232 }
233 
234 
238 void *
240 {
241  struct GNUNET_BLOCK_PluginFunctions *api = cls;
242 
243  GNUNET_free(api);
244  return NULL;
245 }
246 
247 /* end of plugin_block_gns.c */
Block does not match query (invalid result)
Handle to an initialized block library.
Definition: block.c:53
enum GNUNET_BLOCK_Type * types
0-terminated array of block types supported by this plugin.
Any type of block, used as a wildcard when searching.
GNUNET_BLOCK_EvaluationFunction evaluate
Main function of a block plugin.
static struct GNUNET_BLOCK_Group * block_plugin_gns_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.
GNUNET_BLOCK_Type
Blocks in the datastore and the datacache must have a unique type.
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:173
Each plugin is required to return a pointer to a struct of this type as the return value from its ent...
static enum GNUNET_BLOCK_EvaluationResult block_plugin_gns_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_OK
Named constants for return values.
Definition: gnunet_common.h:75
#define GNUNET_new(type)
Allocate a struct or union of the given type.
Information we have in an encrypted block with record data (i.e.
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:248
#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.
Valid result, but suppressed because it is a duplicate.
#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:44
void * libgnunet_plugin_block_gns_done(void *cls)
Exit point from the plugin.
an ECC signature using ECDSA
uint32_t size
How many bytes does this signature sign? (including this purpose header); in network byte order (!)...
Block for storing record data.
A 512-bit hashcode.
static int block_plugin_gns_get_key(void *cls, enum GNUNET_BLOCK_Type type, const void *reply_block, size_t reply_block_size, struct GNUNET_HashCode *key)
Function called to obtain the key for a block.
Valid result, and there may be more.
int GNUNET_GNSRECORD_block_verify(const struct GNUNET_GNSRECORD_Block *block)
Check if a signature is valid.
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.
#define GNS_BF_SIZE
How big is the BF we use for GNS blocks?
GNUNET_BLOCK_EvaluationResult
Possible ways for how a block may relate to a query.
#define GNUNET_memcmp(a, b)
Compare memory in a and b, where both must be of the same pointer type.
Specified block type not supported by this plugin.
GNUNET_BLOCK_GetKeyFunction get_key
Obtain the key for a given block (if possible).
Public ECC key (always for Curve25519) encoded in a format suitable for network transmission and ECDS...
Query format does not match block type (invalid query).
#define BLOOMFILTER_K
Number of bits we set per entry in the bloomfilter.
Block group data.
enum GNUNET_TESTBED_UnderlayLinkModelType type
the type of this model
void * libgnunet_plugin_block_gns_init(void *cls)
Entry point for the plugin.
#define GNUNET_YES
Definition: gnunet_common.h:77
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:212
void * cls
Closure for all of the callbacks.
GNUNET_BLOCK_EvaluationOptions
Flags that can be set to control the evaluation.
struct GNUNET_CRYPTO_EccSignaturePurpose purpose
Number of bytes signed; also specifies the number of bytes of encrypted data that follow...
Query is valid, no reply given.
struct GNUNET_CRYPTO_EcdsaPublicKey derived_key
Derived key used for signing; hash of this is the query.
#define GNUNET_free(ptr)
Wrapper around free.