GNUnet  0.17.6
plugin_block_fs.c
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1 /*
2  This file is part of GNUnet
3  Copyright (C) 2010, 2013, 2021 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 
52 static struct GNUNET_BLOCK_Group *
55  const void *raw_data,
56  size_t raw_data_size,
57  va_list va)
58 {
59  unsigned int size;
60  const char *guard;
61 
62  switch (type)
63  {
65  GNUNET_break (NULL == va_arg (va, const char *));
66  return NULL;
68  GNUNET_break (NULL == va_arg (va, const char *));
69  return NULL;
71  guard = va_arg (va, const char *);
72  if (0 == strcmp (guard,
73  "seen-set-size"))
74  {
76  int),
78  }
79  else if (0 == strcmp (guard,
80  "filter-size"))
81  {
82  size = va_arg (va, unsigned int);
83  }
84  else
85  {
86  /* va-args invalid! bad bug, complain! */
87  GNUNET_break (0);
88  size = 8;
89  }
90  if (0 == size)
91  size = raw_data_size; /* not for us to determine, use what we got! */
92  GNUNET_break (NULL == va_arg (va, const char *));
93  return GNUNET_BLOCK_GROUP_bf_create (cls,
94  size,
96  type,
97  raw_data,
98  raw_data_size);
99 
100  default:
101  GNUNET_break (NULL == va_arg (va, const char *));
102  GNUNET_break (0);
103  return NULL;
104  }
105 }
106 
107 
119 static enum GNUNET_GenericReturnValue
120 block_plugin_fs_get_key (void *cls,
121  enum GNUNET_BLOCK_Type type,
122  const void *block,
123  size_t block_size,
124  struct GNUNET_HashCode *key)
125 {
126  const struct UBlock *ub;
127 
128  switch (type)
129  {
132  GNUNET_CRYPTO_hash (block,
133  block_size,
134  key);
135  return GNUNET_OK;
137  if (block_size < sizeof(struct UBlock))
138  {
139  GNUNET_break_op (0);
140  memset (key,
141  0,
142  sizeof (*key));
143  return GNUNET_OK;
144  }
145  ub = block;
147  sizeof(ub->verification_key),
148  key);
149  return GNUNET_OK;
150  default:
151  GNUNET_break (0);
152  return GNUNET_SYSERR;
153  }
154 }
155 
156 
168 static enum GNUNET_GenericReturnValue
169 block_plugin_fs_check_query (void *cls,
170  enum GNUNET_BLOCK_Type type,
171  const struct GNUNET_HashCode *query,
172  const void *xquery,
173  size_t xquery_size)
174 {
175  switch (type)
176  {
180  if (0 != xquery_size)
181  {
182  GNUNET_break_op (0);
183  return GNUNET_NO;
184  }
185  return GNUNET_OK;
186  default:
187  GNUNET_break (0);
188  return GNUNET_SYSERR;
189  }
190 }
191 
192 
202 static enum GNUNET_GenericReturnValue
203 block_plugin_fs_check_block (void *cls,
204  enum GNUNET_BLOCK_Type type,
205  const void *block,
206  size_t block_size)
207 {
208  switch (type)
209  {
212  return GNUNET_OK;
214  {
215  const struct UBlock *ub;
216 
217  if (block_size < sizeof(struct UBlock))
218  {
219  GNUNET_break_op (0);
220  return GNUNET_NO;
221  }
222  ub = block;
223  if (block_size !=
224  ntohl (ub->purpose.size)
225  + sizeof (struct GNUNET_CRYPTO_EcdsaSignature))
226  {
227  GNUNET_break_op (0);
228  return GNUNET_NO;
229  }
230  if (GNUNET_OK !=
232  &ub->purpose,
233  &ub->signature,
234  &ub->verification_key))
235  {
236  GNUNET_break_op (0);
237  return GNUNET_NO;
238  }
239  return GNUNET_OK;
240  }
241  default:
242  GNUNET_break (0);
243  return GNUNET_SYSERR;
244  }
245 }
246 
247 
265 block_plugin_fs_check_reply (void *cls,
266  enum GNUNET_BLOCK_Type type,
267  struct GNUNET_BLOCK_Group *group,
268  const struct GNUNET_HashCode *query,
269  const void *xquery,
270  size_t xquery_size,
271  const void *reply_block,
272  size_t reply_block_size)
273 {
274  switch (type)
275  {
280  {
281  struct GNUNET_HashCode chash;
282 
283  GNUNET_CRYPTO_hash (reply_block,
284  reply_block_size,
285  &chash);
286  if (GNUNET_YES ==
288  &chash))
291  }
292  default:
293  GNUNET_break (0);
295  }
296 }
297 
298 
302 void *
304 {
305  static const enum GNUNET_BLOCK_Type types[] = {
309  GNUNET_BLOCK_TYPE_ANY /* end of list */
310  };
311  struct GNUNET_BLOCK_PluginFunctions *api;
312 
319  api->types = types;
320  return api;
321 }
322 
323 
327 void *
329 {
330  struct GNUNET_BLOCK_PluginFunctions *api = cls;
331 
332  GNUNET_free (api);
333  return NULL;
334 }
335 
336 
337 /* end of plugin_block_fs.c */
struct GNUNET_HashCode key
The key used in the DHT.
API for block plugins.
GNUNET_BLOCK_Type
WARNING: This header is generated! In order to add DHT block types, you must register them in GANA,...
@ GNUNET_BLOCK_TYPE_FS_DBLOCK
Data block (leaf) in the CHK tree.
@ GNUNET_BLOCK_TYPE_FS_IBLOCK
Inner block in the CHK tree.
@ GNUNET_BLOCK_TYPE_ANY
Identifier for any block.
@ GNUNET_BLOCK_TYPE_FS_UBLOCK
Type of a block representing any type of search result (universal).
API for file sharing via GNUnet.
#define GNUNET_SIGNATURE_PURPOSE_FS_UBLOCK
UBlock Signature, done using DSS, not ECC (GNUnet-FS)
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_OK_LAST
Last possible valid result.
@ GNUNET_BLOCK_REPLY_TYPE_NOT_SUPPORTED
Specified block type not supported by any plugin.
enum GNUNET_GenericReturnValue 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:643
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
GNUNET_GenericReturnValue
Named constants for return values.
Definition: gnunet_common.h:96
@ GNUNET_OK
Definition: gnunet_common.h:99
@ GNUNET_YES
@ GNUNET_NO
Definition: gnunet_common.h:98
@ GNUNET_SYSERR
Definition: gnunet_common.h:97
#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.
#define GNUNET_new(type)
Allocate a struct or union of the given type.
#define GNUNET_free(ptr)
Wrapper around free.
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.
static enum GNUNET_GenericReturnValue block_plugin_fs_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 struct GNUNET_BLOCK_Group * block_plugin_fs_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.
static enum GNUNET_GenericReturnValue 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.
#define BLOOMFILTER_K
Number of bits we set per entry in the bloomfilter.
void * libgnunet_plugin_block_fs_init(void *cls)
Entry point for the plugin.
static enum GNUNET_GenericReturnValue block_plugin_fs_check_block(void *cls, enum GNUNET_BLOCK_Type type, const void *block, size_t block_size)
Function called to validate a block for storage.
static enum GNUNET_BLOCK_ReplyEvaluationResult block_plugin_fs_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.
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 ECDSA
A 512-bit hashcode.
universal block for keyword and namespace search results
Definition: block_fs.h:50
struct GNUNET_CRYPTO_EcdsaPublicKey verification_key
Public key used to sign this block.
Definition: block_fs.h:64
struct GNUNET_CRYPTO_EccSignaturePurpose purpose
What is being signed and why?
Definition: block_fs.h:59
struct GNUNET_CRYPTO_EcdsaSignature signature
Signature using pseudonym and search keyword / identifier.
Definition: block_fs.h:54
enum GNUNET_TESTBED_UnderlayLinkModelType type
the type of this model