GNUnet  0.11.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
73  int),
75  else if (0 == strcmp (guard,
76  "filter-size"))
77  bf_size = va_arg (va, unsigned int);
78  else
79  {
80  GNUNET_break (0);
81  bf_size = GNS_BF_SIZE;
82  }
83  GNUNET_break (NULL == va_arg (va, const char *));
84  return GNUNET_BLOCK_GROUP_bf_create (cls,
85  bf_size,
87  type,
88  nonce,
89  raw_data,
90  raw_data_size);
91 }
92 
93 
115  struct GNUNET_BLOCK_Context *ctx,
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  const struct GNUNET_GNSRECORD_Block *block;
126  struct GNUNET_HashCode h;
127  struct GNUNET_HashCode chash;
128 
131  if (NULL == reply_block)
132  {
133  if (0 != xquery_size)
134  {
135  GNUNET_break_op (0);
137  }
139  }
140 
141  /* this is a reply */
142  if (reply_block_size < sizeof(struct GNUNET_GNSRECORD_Block))
143  {
144  GNUNET_break_op (0);
146  }
147  block = reply_block;
148  if (GNUNET_GNSRECORD_block_get_size (block) > reply_block_size)
149  {
150  GNUNET_break_op (0);
152  }
154  &h);
155  if (0 != GNUNET_memcmp (&h, query))
156  {
157  GNUNET_break_op (0);
159  }
160  if (GNUNET_OK !=
162  {
163  GNUNET_break_op (0);
165  }
166  GNUNET_CRYPTO_hash (reply_block,
167  reply_block_size,
168  &chash);
169  if (GNUNET_YES ==
171  &chash))
174 }
175 
176 
188 static int
190  enum GNUNET_BLOCK_Type type,
191  const void *reply_block,
192  size_t reply_block_size,
193  struct GNUNET_HashCode *key)
194 {
195  const struct GNUNET_GNSRECORD_Block *block;
196 
198  return GNUNET_SYSERR;
199  if (reply_block_size < sizeof(struct GNUNET_GNSRECORD_Block))
200  {
201  GNUNET_break_op (0);
203  }
204  block = reply_block;
206  key);
207  return GNUNET_OK;
208 }
209 
210 
214 void *
216 {
217  static enum GNUNET_BLOCK_Type types[] = {
219  GNUNET_BLOCK_TYPE_ANY /* end of list */
220  };
221  struct GNUNET_BLOCK_PluginFunctions *api;
222 
227  api->types = types;
228  return api;
229 }
230 
231 
235 void *
237 {
238  struct GNUNET_BLOCK_PluginFunctions *api = cls;
239 
240  GNUNET_free (api);
241  return NULL;
242 }
243 
244 
245 /* end of plugin_block_gns.c */
Block does not match query (invalid result)
Handle to an initialized block library.
Definition: block.c:54
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:174
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_new(type)
Allocate a struct or union of the given type.
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
#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.
size_t GNUNET_GNSRECORD_block_get_size(const struct GNUNET_GNSRECORD_Block *block)
Returns the length of this block in bytes.
#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:41
void * libgnunet_plugin_block_gns_done(void *cls)
Exit point from the plugin.
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.
enum GNUNET_GenericReturnValue 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.
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).
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_GenericReturnValue GNUNET_GNSRECORD_query_from_block(const struct GNUNET_GNSRECORD_Block *block, struct GNUNET_HashCode *query)
Builds the query hash from a block.
enum GNUNET_TESTBED_UnderlayLinkModelType type
the type of this model
void * libgnunet_plugin_block_gns_init(void *cls)
Entry point for the plugin.
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.
#define GNUNET_free(ptr)
Wrapper around free.