GNUnet  0.10.x
plugin_block_revocation.c
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1 /*
2  This file is part of GNUnet
3  Copyright (C) 2017 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 
27 #include "platform.h"
28 #include "gnunet_signatures.h"
29 #include "gnunet_block_plugin.h"
30 #include "gnunet_block_group_lib.h"
31 #include "revocation.h"
33 
34 #define DEBUG_REVOCATION GNUNET_EXTRA_LOGGING
35 
40 #define BLOOMFILTER_K 16
41 
42 
46 #define REVOCATION_BF_SIZE 8
47 
48 
53  unsigned int matching_bits;
54 };
55 
56 
69 static struct GNUNET_BLOCK_Group *
72  uint32_t nonce,
73  const void *raw_data,
74  size_t raw_data_size,
75  va_list va)
76 {
77  unsigned int bf_size;
78  const char *guard;
79 
80  guard = va_arg(va, const char *);
81  if (0 == strcmp(guard,
82  "seen-set-size"))
83  bf_size = GNUNET_BLOCK_GROUP_compute_bloomfilter_size(va_arg(va, unsigned int),
85  else if (0 == strcmp(guard,
86  "filter-size"))
87  bf_size = va_arg(va, unsigned int);
88  else
89  {
90  GNUNET_break(0);
91  bf_size = REVOCATION_BF_SIZE;
92  }
93  GNUNET_break(NULL == va_arg(va, const char *));
95  bf_size,
97  type,
98  nonce,
99  raw_data,
100  raw_data_size);
101 }
102 
103 
122  struct GNUNET_BLOCK_Context *ctx,
123  enum GNUNET_BLOCK_Type type,
124  struct GNUNET_BLOCK_Group *group,
126  const struct GNUNET_HashCode *query,
127  const void *xquery,
128  size_t xquery_size,
129  const void *reply_block,
130  size_t reply_block_size)
131 {
132  struct InternalContext *ic = cls;
133  struct GNUNET_HashCode chash;
134  const struct RevokeMessage *rm = reply_block;
135 
136  if (NULL == reply_block)
138  if (reply_block_size != sizeof(*rm))
139  {
140  GNUNET_break_op(0);
142  }
143  if (GNUNET_YES !=
145  rm->proof_of_work,
146  ic->matching_bits))
147  {
148  GNUNET_break_op(0);
150  }
151  if (GNUNET_OK !=
153  &rm->purpose,
154  &rm->signature,
155  &rm->public_key))
156  {
157  GNUNET_break_op(0);
159  }
161  sizeof(struct GNUNET_CRYPTO_EcdsaPublicKey),
162  &chash);
163  if (GNUNET_YES ==
165  &chash))
168 }
169 
170 
182 static int
184  enum GNUNET_BLOCK_Type type,
185  const void *block,
186  size_t block_size,
187  struct GNUNET_HashCode *key)
188 {
189  const struct RevokeMessage *rm = block;
190 
191  if (block_size != sizeof(*rm))
192  {
193  GNUNET_break_op(0);
194  return GNUNET_SYSERR;
195  }
197  sizeof(struct GNUNET_CRYPTO_EcdsaPublicKey),
198  key);
199  return GNUNET_OK;
200 }
201 
202 
208 void *
210 {
211  static enum GNUNET_BLOCK_Type types[] =
212  {
214  GNUNET_BLOCK_TYPE_ANY /* end of list */
215  };
216  const struct GNUNET_CONFIGURATION_Handle *cfg = cls;
217  struct GNUNET_BLOCK_PluginFunctions *api;
218  struct InternalContext *ic;
219  unsigned long long matching_bits;
220 
221  if (GNUNET_OK !=
223  "REVOCATION",
224  "WORKBITS",
225  &matching_bits))
226  return NULL;
227 
232  api->types = types;
233  ic = GNUNET_new(struct InternalContext);
234  ic->matching_bits = (unsigned int)matching_bits;
235  api->cls = ic;
236  return api;
237 }
238 
239 
243 void *
245 {
246  struct GNUNET_BLOCK_PluginFunctions *api = cls;
247  struct InternalContext *ic = api->cls;
248 
249  GNUNET_free(ic);
250  GNUNET_free(api);
251  return NULL;
252 }
253 
254 /* end of plugin_block_revocation.c */
Block does not match query (invalid result)
static struct GNUNET_BLOCK_Group * block_plugin_revocation_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.
Handle to an initialized block library.
Definition: block.c:53
struct GNUNET_CRYPTO_EcdsaSignature signature
Signature confirming revocation.
Definition: revocation.h:96
int GNUNET_CONFIGURATION_get_value_number(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, unsigned long long *number)
Get a configuration value that should be a number.
void * libgnunet_plugin_block_revocation_init(void *cls)
Entry point for the plugin.
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
static enum GNUNET_BLOCK_EvaluationResult block_plugin_revocation_evaluate(void *cls, struct GNUNET_BLOCK_Context *ctx, enum GNUNET_BLOCK_Type type, struct GNUNET_BLOCK_Group *group, 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.
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 REVOCATION_BF_SIZE
How big is the BF we use for DHT blocks?
Block type for a revocation message by which a key is revoked.
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...
Context used inside the plugin.
struct GNUNET_CRYPTO_EccSignaturePurpose purpose
Must have purpose GNUNET_SIGNATURE_PURPOSE_REVOCATION, size expands over the public key...
Definition: revocation.h:102
#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_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_revocation_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.
Revoke key.
Definition: revocation.h:77
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
messages for key revocation
uint64_t proof_of_work
Number that causes a hash collision with the public_key.
Definition: revocation.h:91
A 512-bit hashcode.
static struct GNUNET_CONFIGURATION_Handle * cfg
Our configuration.
Definition: gnunet-arm.c:104
#define GNUNET_SIGNATURE_PURPOSE_REVOCATION
Signature for confirming a key revocation.
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.
void * libgnunet_plugin_block_revocation_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.
#define BLOOMFILTER_K
Number of bits we set per entry in the bloomfilter.
GNUNET_BLOCK_GetKeyFunction get_key
Obtain the key for a given block (if possible).
configuration data
Definition: configuration.c:83
Public ECC key (always for Curve25519) encoded in a format suitable for network transmission and ECDS...
Block group data.
enum GNUNET_TESTBED_UnderlayLinkModelType type
the type of this model
struct GNUNET_CRYPTO_EcdsaPublicKey public_key
Key to revoke.
Definition: revocation.h:107
#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.
Query is valid, no reply given.
#define GNUNET_free(ptr)
Wrapper around free.
int GNUNET_REVOCATION_check_pow(const struct GNUNET_CRYPTO_EcdsaPublicKey *key, uint64_t pow, unsigned int matching_bits)
Check if the given proof-of-work value would be acceptable for revoking the given key...