GNUnet 0.21.1
plugin_block_dns.c
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1/*
2 This file is part of GNUnet
3 Copyright (C) 2013, 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
30#include "platform.h"
31#include "gnunet_block_plugin.h"
32#include "block_dns.h"
33#include "gnunet_signatures.h"
35
36
41#define BLOOMFILTER_K 16
42
43
55static struct GNUNET_BLOCK_Group *
58 const void *raw_data,
59 size_t raw_data_size,
60 va_list va)
61{
62 unsigned int bf_size;
63 const char *guard;
64
65 guard = va_arg (va, const char *);
66 if (0 == strcmp (guard,
67 "seen-set-size"))
68 bf_size = GNUNET_BLOCK_GROUP_compute_bloomfilter_size (va_arg (va, unsigned
69 int),
71 else if (0 == strcmp (guard,
72 "filter-size"))
73 bf_size = va_arg (va, unsigned int);
74 else
75 {
76 GNUNET_break (0);
77 bf_size = 8;
78 }
79 GNUNET_break (NULL == va_arg (va, const char *));
81 bf_size,
83 type,
84 raw_data,
85 raw_data_size);
86}
87
88
102 const struct GNUNET_HashCode *query,
103 const void *xquery,
104 size_t xquery_size)
105{
106 switch (type)
107 {
109 if (0 != xquery_size)
110 {
111 GNUNET_break_op (0);
112 return GNUNET_NO;
113 }
114 return GNUNET_OK;
115 default:
116 GNUNET_break (0);
117 return GNUNET_SYSERR;
118 }
119}
120
121
134 const void *block,
135 size_t block_size)
136{
137 const struct GNUNET_DNS_Advertisement *ad;
138
139 switch (type)
140 {
142 if (sizeof(struct GNUNET_DNS_Advertisement) != block_size)
143 {
144 GNUNET_break_op (0);
145 return GNUNET_NO;
146 }
147 ad = block;
148
149 if (ntohl (ad->purpose.size) !=
150 sizeof(struct GNUNET_DNS_Advertisement)
151 - sizeof(struct GNUNET_CRYPTO_EddsaSignature))
152 {
153 GNUNET_break_op (0);
154 return GNUNET_NO;
155 }
158 {
160 "DNS advertisement has expired\n");
161 return GNUNET_NO;
162 }
163 if (GNUNET_OK !=
165 &ad->purpose,
166 &ad->signature,
167 &ad->peer.public_key))
168 {
169 GNUNET_break_op (0);
170 return GNUNET_NO;
171 }
172 return GNUNET_OK;
173 default:
174 GNUNET_break (0);
175 return GNUNET_SYSERR;
176 }
177}
178
179
198 void *cls,
200 struct GNUNET_BLOCK_Group *group,
201 const struct GNUNET_HashCode *query,
202 const void *xquery,
203 size_t xquery_size,
204 const void *reply_block,
205 size_t reply_block_size)
206{
207 struct GNUNET_HashCode phash;
208
209 switch (type)
210 {
212 GNUNET_CRYPTO_hash (reply_block,
213 reply_block_size,
214 &phash);
215 if (GNUNET_YES ==
217 &phash))
220 default:
221 GNUNET_break (0);
223 }
224}
225
226
241 const void *block,
242 size_t block_size,
243 struct GNUNET_HashCode *key)
244{
246 {
247 GNUNET_break (0);
248 return GNUNET_SYSERR;
249 }
250 return GNUNET_NO;
251}
252
253
257void *
259{
260 static enum GNUNET_BLOCK_Type types[] = {
262 GNUNET_BLOCK_TYPE_ANY /* end of list */
263 };
265
272 api->types = types;
273 return api;
274}
275
276
280void *
282{
283 struct GNUNET_BLOCK_PluginFunctions *api = cls;
284
285 GNUNET_free (api);
286 return NULL;
287}
288
289
290/* end of plugin_block_dns.c */
DNS network structs.
struct GNUNET_HashCode key
The key used in the DHT.
static uint32_t type
Type string converted to DNS type value.
API for block plugins.
enum GNUNET_GenericReturnValue 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:232
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?...
Definition: bg_bf.c:268
GNUNET_BLOCK_ReplyEvaluationResult
Possible ways for how a block may relate to a query.
struct GNUNET_BLOCK_Group * GNUNET_BLOCK_GROUP_bf_create(void *cls, size_t bf_size, unsigned int bf_k, enum GNUNET_BLOCK_Type type, 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
@ GNUNET_BLOCK_REPLY_OK_MORE
Valid result, and there may be more.
@ GNUNET_BLOCK_REPLY_OK_DUPLICATE
Valid result, but suppressed because it is a duplicate.
@ GNUNET_BLOCK_REPLY_TYPE_NOT_SUPPORTED
Specified block type not supported by any plugin.
enum GNUNET_GenericReturnValue GNUNET_CRYPTO_eddsa_verify_(uint32_t purpose, const struct GNUNET_CRYPTO_EccSignaturePurpose *validate, const struct GNUNET_CRYPTO_EddsaSignature *sig, const struct GNUNET_CRYPTO_EddsaPublicKey *pub)
Verify EdDSA signature.
Definition: crypto_ecc.c:705
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
#define GNUNET_log(kind,...)
GNUNET_GenericReturnValue
Named constants for return values.
@ GNUNET_OK
@ GNUNET_YES
@ GNUNET_NO
@ GNUNET_SYSERR
#define GNUNET_break_op(cond)
Use this for assertion violations caused by other peers (i.e.
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur.
@ GNUNET_ERROR_TYPE_DEBUG
#define GNUNET_new(type)
Allocate a struct or union of the given type.
#define GNUNET_free(ptr)
Wrapper around free.
struct GNUNET_TIME_Absolute GNUNET_TIME_absolute_ntoh(struct GNUNET_TIME_AbsoluteNBO a)
Convert absolute time from network byte order.
Definition: time.c:737
bool GNUNET_TIME_absolute_is_past(struct GNUNET_TIME_Absolute abs)
Test if abs is truly in the past (excluding now).
Definition: time.c:669
void * libgnunet_plugin_block_dns_init(void *cls)
Entry point for the plugin.
void * libgnunet_plugin_block_dns_done(void *cls)
Exit point from the plugin.
static enum GNUNET_BLOCK_ReplyEvaluationResult block_plugin_dns_check_reply(void *cls, enum GNUNET_BLOCK_Type type, struct GNUNET_BLOCK_Group *group, 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 to a request.
static enum GNUNET_GenericReturnValue block_plugin_dns_check_block(void *cls, enum GNUNET_BLOCK_Type type, const void *block, size_t block_size)
Function called to validate a block for storage.
#define BLOOMFILTER_K
Number of bits we set per entry in the bloomfilter.
static enum GNUNET_GenericReturnValue block_plugin_dns_check_query(void *cls, enum GNUNET_BLOCK_Type type, const struct GNUNET_HashCode *query, const void *xquery, size_t xquery_size)
Function called to validate a query.
static enum GNUNET_GenericReturnValue block_plugin_dns_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.
static struct GNUNET_BLOCK_Group * block_plugin_dns_create_group(void *cls, enum GNUNET_BLOCK_Type type, const void *raw_data, size_t raw_data_size, va_list va)
Create a new block group.
GNUNET_BLOCK_Type
WARNING: This header is generated! In order to add DHT block types, you must register them in GANA,...
@ GNUNET_BLOCK_TYPE_DNS
Block for storing DNS exit service advertisements.
@ GNUNET_BLOCK_TYPE_ANY
Identifier for any block.
#define GNUNET_SIGNATURE_PURPOSE_DNS_RECORD
Signature on a GNUNET_DNS_Advertisement.
Block group data.
Each plugin is required to return a pointer to a struct of this type as the return value from its ent...
enum GNUNET_BLOCK_Type * types
0-terminated array of block types supported by this plugin.
GNUNET_BLOCK_QueryEvaluationFunction check_query
Check that a query is well-formed.
GNUNET_BLOCK_BlockEvaluationFunction check_block
Check that a block is well-formed.
GNUNET_BLOCK_GetKeyFunction get_key
Obtain the key for a given block (if possible).
GNUNET_BLOCK_ReplyEvaluationFunction check_reply
Check that a reply block matches a query.
GNUNET_BLOCK_GroupCreateFunction create_group
Create a block group to process a bunch of blocks in a shared context (i.e.
void * cls
Closure for all of the callbacks.
uint32_t size
How many bytes does this signature sign? (including this purpose header); in network byte order (!...
an ECC signature using EdDSA.
This is the structure describing an DNS exit service.
Definition: block_dns.h:45
struct GNUNET_PeerIdentity peer
The peer providing this service.
Definition: block_dns.h:65
struct GNUNET_TIME_AbsoluteNBO expiration_time
When does this signature expire?
Definition: block_dns.h:60
struct GNUNET_CRYPTO_EddsaSignature signature
Signature of the peer affirming that it is offering the service.
Definition: block_dns.h:49
struct GNUNET_CRYPTO_EccSignaturePurpose purpose
Beginning of signed portion of the record, signs everything until the end of the struct.
Definition: block_dns.h:55
A 512-bit hashcode.
struct GNUNET_CRYPTO_EddsaPublicKey public_key