GNUnet  0.10.x
plugin_block_fs.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 
26 #include "platform.h"
27 #include "gnunet_block_plugin.h"
28 #include "gnunet_fs_service.h"
29 #include "block_fs.h"
30 #include "gnunet_signatures.h"
31 #include "gnunet_block_group_lib.h"
32 
33 
38 #define BLOOMFILTER_K 16
39 
40 
53 static struct GNUNET_BLOCK_Group *
56  uint32_t nonce,
57  const void *raw_data,
58  size_t raw_data_size,
59  va_list va)
60 {
61  unsigned int size;
62  const char *guard;
63 
64  switch (type)
65  {
67  GNUNET_break (NULL == va_arg (va, const char *));
68  return NULL;
70  GNUNET_break (NULL == va_arg (va, const char *));
71  return NULL;
73  guard = va_arg (va, const char *);
74  if (0 == strcmp (guard,
75  "seen-set-size"))
76  {
77  size = GNUNET_BLOCK_GROUP_compute_bloomfilter_size (va_arg (va, unsigned int),
79  }
80  else if (0 == strcmp (guard,
81  "filter-size"))
82  {
83  size = va_arg (va, unsigned int);
84  }
85  else
86  {
87  /* va-args invalid! bad bug, complain! */
88  GNUNET_break (0);
89  size = 8;
90  }
91  if (0 == size)
92  size = raw_data_size; /* not for us to determine, use what we got! */
93  GNUNET_break (NULL == va_arg (va, const char *));
94  return GNUNET_BLOCK_GROUP_bf_create (cls,
95  size,
97  type,
98  nonce,
99  raw_data,
100  raw_data_size);
101  default:
102  GNUNET_break (NULL == va_arg (va, const char *));
103  GNUNET_break (0);
104  return NULL;
105  }
106 }
107 
108 
130  struct GNUNET_BLOCK_Context *ctx,
131  enum GNUNET_BLOCK_Type type,
132  struct GNUNET_BLOCK_Group *bg,
134  const struct GNUNET_HashCode *query,
135  const void *xquery,
136  size_t xquery_size,
137  const void *reply_block,
138  size_t reply_block_size)
139 {
140  const struct UBlock *ub;
141  struct GNUNET_HashCode hc;
142  struct GNUNET_HashCode chash;
143 
144  switch (type)
145  {
148  if (0 != xquery_size)
149  {
150  GNUNET_break_op (0);
152  }
153  if (NULL == reply_block)
157  if (0 != xquery_size)
158  {
159  GNUNET_break_op (0);
161  }
162  if (NULL == reply_block)
164 
165  if (reply_block_size < sizeof (struct UBlock))
166  {
167  GNUNET_break_op (0);
169  }
170  ub = reply_block;
172  sizeof (ub->verification_key),
173  &hc);
174  if (0 != memcmp (&hc,
175  query,
176  sizeof (struct GNUNET_HashCode)))
177  {
178  GNUNET_break_op (0);
180  }
181  if (reply_block_size != ntohl (ub->purpose.size) + sizeof (struct GNUNET_CRYPTO_EcdsaSignature))
182  {
183  GNUNET_break_op (0);
185  }
186  if ( (0 == (eo & GNUNET_BLOCK_EO_LOCAL_SKIP_CRYPTO)) &&
187  (GNUNET_OK !=
189  &ub->purpose,
190  &ub->signature,
191  &ub->verification_key)) )
192  {
193  GNUNET_break_op (0);
195  }
196  GNUNET_CRYPTO_hash (reply_block,
197  reply_block_size,
198  &chash);
199  if (GNUNET_YES ==
201  &chash))
204  default:
206  }
207 }
208 
209 
221 static int
223  enum GNUNET_BLOCK_Type type,
224  const void *block,
225  size_t block_size,
226  struct GNUNET_HashCode *key)
227 {
228  const struct UBlock *ub;
229 
230  switch (type)
231  {
234  GNUNET_CRYPTO_hash (block, block_size, key);
235  return GNUNET_OK;
237  if (block_size < sizeof (struct UBlock))
238  {
239  GNUNET_break (0);
240  return GNUNET_SYSERR;
241  }
242  ub = block;
244  sizeof (ub->verification_key),
245  key);
246  return GNUNET_OK;
247  default:
248  GNUNET_break (0);
249  return GNUNET_SYSERR;
250  }
251 }
252 
253 
257 void *
259 {
260  static enum GNUNET_BLOCK_Type types[] =
261  {
265  GNUNET_BLOCK_TYPE_ANY /* end of list */
266  };
267  struct GNUNET_BLOCK_PluginFunctions *api;
268 
273  api->types = types;
274  return api;
275 }
276 
277 
281 void *
283 {
284  struct GNUNET_BLOCK_PluginFunctions *api = cls;
285 
286  GNUNET_free (api);
287  return NULL;
288 }
289 
290 /* end of plugin_block_fs.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.
int GNUNET_CRYPTO_ecdsa_verify(uint32_t purpose, const struct GNUNET_CRYPTO_EccSignaturePurpose *validate, const struct GNUNET_CRYPTO_EcdsaSignature *sig, const struct GNUNET_CRYPTO_EcdsaPublicKey *pub)
Verify ECDSA signature.
Definition: crypto_ecc.c:1048
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.
#define BLOOMFILTER_K
Number of bits we set per entry in the bloomfilter.
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:175
Each plugin is required to return a pointer to a struct of this type as the return value from its ent...
#define GNUNET_OK
Named constants for return values.
Definition: gnunet_common.h:78
#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_SIGNATURE_PURPOSE_FS_UBLOCK
UBlock Signature, done using DSS, not ECC.
#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.
static int block_plugin_fs_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.
struct GNUNET_CRYPTO_EcdsaSignature signature
Signature using pseudonym and search keyword / identifier.
Definition: block_fs.h:56
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
static enum GNUNET_BLOCK_EvaluationResult block_plugin_fs_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.
Inner block in the CHK tree.
Last possible valid result.
an ECC signature using ECDSA
uint32_t size
How many bytes does this signature sign? (including this purpose header); in network byte order (!)...
Type of a block representing any type of search result (universal).
A 512-bit hashcode.
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
GNUNET_BLOCK_GroupCreateFunction create_group
Create a block group to process a bunch of blocks in a shared context (i.e.
static unsigned int size
Size of the "table".
Definition: peer.c:67
void * libgnunet_plugin_block_fs_done(void *cls)
Exit point from the plugin.
GNUNET_BLOCK_EvaluationResult
Possible ways for how a block may relate to a query.
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).
Data block (leaf) in the CHK tree.
Block group data.
enum GNUNET_TESTBED_UnderlayLinkModelType type
the type of this model
#define GNUNET_YES
Definition: gnunet_common.h:80
void * libgnunet_plugin_block_fs_init(void *cls)
Entry point for the plugin.
static struct GNUNET_BLOCK_Group * block_plugin_fs_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.
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.
struct GNUNET_CRYPTO_EccSignaturePurpose purpose
What is being signed and why?
Definition: block_fs.h:61
Query is valid, no reply given.
struct GNUNET_CRYPTO_EcdsaPublicKey verification_key
Public key used to sign this block.
Definition: block_fs.h:66
universal block for keyword and namespace search results
Definition: block_fs.h:50
#define GNUNET_free(ptr)
Wrapper around free.