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;
69 
71  GNUNET_break(NULL == va_arg(va, const char *));
72  return NULL;
73 
75  guard = va_arg(va, const char *);
76  if (0 == strcmp(guard,
77  "seen-set-size"))
78  {
79  size = GNUNET_BLOCK_GROUP_compute_bloomfilter_size(va_arg(va, unsigned int),
81  }
82  else if (0 == strcmp(guard,
83  "filter-size"))
84  {
85  size = va_arg(va, unsigned int);
86  }
87  else
88  {
89  /* va-args invalid! bad bug, complain! */
90  GNUNET_break(0);
91  size = 8;
92  }
93  if (0 == size)
94  size = raw_data_size; /* not for us to determine, use what we got! */
95  GNUNET_break(NULL == va_arg(va, const char *));
97  size,
99  type,
100  nonce,
101  raw_data,
102  raw_data_size);
103 
104  default:
105  GNUNET_break(NULL == va_arg(va, const char *));
106  GNUNET_break(0);
107  return NULL;
108  }
109 }
110 
111 
133  struct GNUNET_BLOCK_Context *ctx,
134  enum GNUNET_BLOCK_Type type,
135  struct GNUNET_BLOCK_Group *bg,
137  const struct GNUNET_HashCode *query,
138  const void *xquery,
139  size_t xquery_size,
140  const void *reply_block,
141  size_t reply_block_size)
142 {
143  const struct UBlock *ub;
144  struct GNUNET_HashCode hc;
145  struct GNUNET_HashCode chash;
146 
147  switch (type)
148  {
151  if (0 != xquery_size)
152  {
153  GNUNET_break_op(0);
155  }
156  if (NULL == reply_block)
159 
161  if (0 != xquery_size)
162  {
163  GNUNET_break_op(0);
165  }
166  if (NULL == reply_block)
168 
169  if (reply_block_size < sizeof(struct UBlock))
170  {
171  GNUNET_break_op(0);
173  }
174  ub = reply_block;
176  sizeof(ub->verification_key),
177  &hc);
178  if (0 != memcmp(&hc,
179  query,
180  sizeof(struct GNUNET_HashCode)))
181  {
182  GNUNET_break_op(0);
184  }
185  if (reply_block_size != ntohl(ub->purpose.size) + sizeof(struct GNUNET_CRYPTO_EcdsaSignature))
186  {
187  GNUNET_break_op(0);
189  }
190  if ((0 == (eo & GNUNET_BLOCK_EO_LOCAL_SKIP_CRYPTO)) &&
191  (GNUNET_OK !=
193  &ub->purpose,
194  &ub->signature,
195  &ub->verification_key)))
196  {
197  GNUNET_break_op(0);
199  }
200  GNUNET_CRYPTO_hash(reply_block,
201  reply_block_size,
202  &chash);
203  if (GNUNET_YES ==
205  &chash))
208 
209  default:
211  }
212 }
213 
214 
226 static int
228  enum GNUNET_BLOCK_Type type,
229  const void *block,
230  size_t block_size,
231  struct GNUNET_HashCode *key)
232 {
233  const struct UBlock *ub;
234 
235  switch (type)
236  {
239  GNUNET_CRYPTO_hash(block, block_size, key);
240  return GNUNET_OK;
241 
243  if (block_size < sizeof(struct UBlock))
244  {
245  GNUNET_break(0);
246  return GNUNET_SYSERR;
247  }
248  ub = block;
250  sizeof(ub->verification_key),
251  key);
252  return GNUNET_OK;
253 
254  default:
255  GNUNET_break(0);
256  return GNUNET_SYSERR;
257  }
258 }
259 
260 
264 void *
266 {
267  static enum GNUNET_BLOCK_Type types[] =
268  {
272  GNUNET_BLOCK_TYPE_ANY /* end of list */
273  };
274  struct GNUNET_BLOCK_PluginFunctions *api;
275 
280  api->types = types;
281  return api;
282 }
283 
284 
288 void *
290 {
291  struct GNUNET_BLOCK_PluginFunctions *api = cls;
292 
293  GNUNET_free(api);
294  return NULL;
295 }
296 
297 /* end of plugin_block_fs.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.
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:173
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:75
#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:248
#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:54
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:76
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:66
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:77
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: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
What is being signed and why?
Definition: block_fs.h:59
Query is valid, no reply given.
struct GNUNET_CRYPTO_EcdsaPublicKey verification_key
Public key used to sign this block.
Definition: block_fs.h:64
universal block for keyword and namespace search results
Definition: block_fs.h:50
#define GNUNET_free(ptr)
Wrapper around free.