GNUnet  0.11.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 {
54  unsigned int matching_bits;
56 };
57 
58 
71 static struct GNUNET_BLOCK_Group *
74  uint32_t nonce,
75  const void *raw_data,
76  size_t raw_data_size,
77  va_list va)
78 {
79  unsigned int bf_size;
80  const char *guard;
81 
82  guard = va_arg (va, const char *);
83  if (0 == strcmp (guard,
84  "seen-set-size"))
85  bf_size = GNUNET_BLOCK_GROUP_compute_bloomfilter_size (va_arg (va, unsigned
86  int),
88  else if (0 == strcmp (guard,
89  "filter-size"))
90  bf_size = va_arg (va, unsigned int);
91  else
92  {
93  GNUNET_break (0);
94  bf_size = REVOCATION_BF_SIZE;
95  }
96  GNUNET_break (NULL == va_arg (va, const char *));
97  return GNUNET_BLOCK_GROUP_bf_create (cls,
98  bf_size,
100  type,
101  nonce,
102  raw_data,
103  raw_data_size);
104 }
105 
106 
125  struct GNUNET_BLOCK_Context *ctx,
126  enum GNUNET_BLOCK_Type type,
127  struct GNUNET_BLOCK_Group *group,
129  const struct GNUNET_HashCode *query,
130  const void *xquery,
131  size_t xquery_size,
132  const void *reply_block,
133  size_t reply_block_size)
134 {
135  struct InternalContext *ic = cls;
136  struct GNUNET_HashCode chash;
137  const struct RevokeMessage *rm = reply_block;
138 
139  if (NULL == reply_block)
141  if (reply_block_size != sizeof(*rm))
142  {
143  GNUNET_break_op (0);
145  }
146  struct GNUNET_REVOCATION_PowP *pow = (struct GNUNET_REVOCATION_PowP *) &rm[1];
147  const struct GNUNET_IDENTITY_PublicKey *pk;
148  pk = (const struct GNUNET_IDENTITY_PublicKey *) &pow[1];
150  ic->matching_bits,
151  ic->epoch_duration))
152  {
153  GNUNET_break_op (0);
155  }
156  GNUNET_CRYPTO_hash (pk,
158  &chash);
159  if (GNUNET_YES ==
161  &chash))
164 }
165 
166 
178 static int
180  enum GNUNET_BLOCK_Type type,
181  const void *block,
182  size_t block_size,
183  struct GNUNET_HashCode *key)
184 {
185  const struct RevokeMessage *rm = block;
186 
187  if (block_size <= sizeof(*rm))
188  {
189  GNUNET_break_op (0);
190  return GNUNET_SYSERR;
191  }
192  struct GNUNET_REVOCATION_PowP *pow = (struct GNUNET_REVOCATION_PowP *) &rm[1];
193  const struct GNUNET_IDENTITY_PublicKey *pk;
194  pk = (const struct GNUNET_IDENTITY_PublicKey *) &pow[1];
195  GNUNET_CRYPTO_hash (pk,
197  key);
198  return GNUNET_OK;
199 }
200 
201 
207 void *
209 {
210  static enum GNUNET_BLOCK_Type types[] = {
212  GNUNET_BLOCK_TYPE_ANY /* end of list */
213  };
214  const struct GNUNET_CONFIGURATION_Handle *cfg = cls;
215  struct GNUNET_BLOCK_PluginFunctions *api;
216  struct InternalContext *ic;
217  unsigned long long matching_bits;
218  struct GNUNET_TIME_Relative epoch_duration;
219 
220  if (GNUNET_OK !=
222  "REVOCATION",
223  "WORKBITS",
224  &matching_bits))
225  return NULL;
226  if (GNUNET_OK !=
228  "REVOCATION",
229  "EPOCH_DURATION",
230  &epoch_duration))
231  return NULL;
232 
237  api->types = types;
238  ic = GNUNET_new (struct InternalContext);
239  ic->matching_bits = (unsigned int) matching_bits;
241  api->cls = ic;
242  return api;
243 }
244 
245 
249 void *
251 {
252  struct GNUNET_BLOCK_PluginFunctions *api = cls;
253  struct InternalContext *ic = api->cls;
254 
255  GNUNET_free (ic);
256  GNUNET_free (api);
257  return NULL;
258 }
259 
260 
261 /* 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:54
int GNUNET_CONFIGURATION_get_value_time(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, struct GNUNET_TIME_Relative *time)
Get a configuration value that should be a relative time.
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.
static const struct GNUNET_CONFIGURATION_Handle * cfg
Configuration we are using.
Definition: gnunet-abd.c:36
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.
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 for a proof of work as part of the revocation.
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...
ssize_t GNUNET_IDENTITY_key_get_length(const struct GNUNET_IDENTITY_PublicKey *key)
Get the compacted length of a GNUNET_IDENTITY_PublicKey.
Definition: identity_api.c:976
Context used inside the plugin.
#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.
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:80
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:48
messages for key revocation
A 512-bit hashcode.
uint64_t pow[32]
The PoWs.
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.
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).
An identity key as per LSD0001.
configuration data
Definition: configuration.c:84
struct GNUNET_IDENTITY_PrivateKey pk
Private key from command line option, or NULL.
Block group data.
struct GNUNET_TIME_Relative epoch_duration
enum GNUNET_TESTBED_UnderlayLinkModelType type
the type of this model
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.
Time for relative time used by GNUnet, in microseconds.
enum GNUNET_GenericReturnValue GNUNET_REVOCATION_check_pow(const struct GNUNET_REVOCATION_PowP *pow, unsigned int matching_bits, struct GNUNET_TIME_Relative epoch_duration)
Check if the given proof-of-work is valid.