GNUnet  0.19.3
plugin_block_dht.c
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1 /*
2  This file is part of GNUnet
3  Copyright (C) 2010, 2017, 2022 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 
28 #include "platform.h"
29 #include "gnunet_constants.h"
30 #include "gnunet_hello_lib.h"
31 #include "gnunet_hello_uri_lib.h"
32 #include "gnunet_block_plugin.h"
33 #include "gnunet_block_group_lib.h"
34 
35 #define DEBUG_DHT GNUNET_EXTRA_LOGGING
36 
41 #define BLOOMFILTER_K 16
42 
43 
55 static 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,
69  unsigned 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 *));
80  return GNUNET_BLOCK_GROUP_bf_create (cls,
81  bf_size,
83  type,
84  raw_data,
85  raw_data_size);
86 }
87 
88 
99 static enum GNUNET_GenericReturnValue
101  enum GNUNET_BLOCK_Type type,
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;
116  if (0 != xquery_size)
117  {
118  GNUNET_break_op (0);
119  return GNUNET_NO;
120  }
121  return GNUNET_OK;
122  default:
123  GNUNET_break (0);
124  return GNUNET_SYSERR;
125  }
126 }
127 
128 
138 static enum GNUNET_GenericReturnValue
140  enum GNUNET_BLOCK_Type type,
141  const void *block,
142  size_t block_size)
143 {
144  switch (type)
145  {
147  {
148  const struct GNUNET_HELLO_Message *hello;
149  struct GNUNET_PeerIdentity pid;
150  const struct GNUNET_MessageHeader *msg;
151 
152  if (block_size < sizeof(struct GNUNET_MessageHeader))
153  {
154  GNUNET_break_op (0);
155  return GNUNET_NO;
156  }
157  msg = block;
158  if (block_size != ntohs (msg->size))
159  {
160  GNUNET_break_op (0);
161  return GNUNET_NO;
162  }
163  hello = block;
164  if (GNUNET_OK !=
165  GNUNET_HELLO_get_id (hello,
166  &pid))
167  {
168  GNUNET_break_op (0);
169  return GNUNET_NO;
170  }
171  return GNUNET_OK;
172  }
174  {
175  struct GNUNET_HELLO_Builder *b;
176  struct GNUNET_PeerIdentity pid;
177  struct GNUNET_HashCode h_pid;
178 
180  block_size);
181  if (NULL == b)
182  {
183  GNUNET_break (0);
184  return GNUNET_NO;
185  }
187  &pid,
188  NULL, NULL);
190  sizeof (pid),
191  &h_pid);
193  return GNUNET_OK;
194  }
195  default:
196  GNUNET_break (0);
197  return GNUNET_SYSERR;
198  }
199 }
200 
201 
220  void *cls,
221  enum GNUNET_BLOCK_Type type,
222  struct GNUNET_BLOCK_Group *group,
223  const struct GNUNET_HashCode *query,
224  const void *xquery,
225  size_t xquery_size,
226  const void *reply_block,
227  size_t reply_block_size)
228 {
229  switch (type)
230  {
232  {
233  /* LEGACY */
234  const struct GNUNET_MessageHeader *msg = reply_block;
235  const struct GNUNET_HELLO_Message *hello = reply_block;
236  struct GNUNET_PeerIdentity pid;
237  struct GNUNET_HashCode phash;
238 
239  GNUNET_assert (reply_block_size >= sizeof(struct GNUNET_MessageHeader));
240  GNUNET_assert (reply_block_size == ntohs (msg->size));
242  GNUNET_HELLO_get_id (hello,
243  &pid));
245  sizeof(pid),
246  &phash);
247  if (GNUNET_YES ==
249  &phash))
252  }
254  {
255  struct GNUNET_HELLO_Builder *b;
256  struct GNUNET_PeerIdentity pid;
257  struct GNUNET_HashCode h_pid;
258 
259  b = GNUNET_HELLO_builder_from_block (reply_block,
260  reply_block_size);
261  GNUNET_assert (NULL != b);
263  &pid,
264  NULL, NULL);
266  sizeof (pid),
267  &h_pid);
269  if (GNUNET_YES ==
271  &h_pid))
274  }
275  default:
277  }
278 }
279 
280 
292 static enum GNUNET_GenericReturnValue
293 block_plugin_dht_get_key (void *cls,
294  enum GNUNET_BLOCK_Type type,
295  const void *block,
296  size_t block_size,
297  struct GNUNET_HashCode *key)
298 {
299  switch (type)
300  {
302  {
303  /* LEGACY */
304  const struct GNUNET_MessageHeader *msg;
305  const struct GNUNET_HELLO_Message *hello;
306  struct GNUNET_PeerIdentity *pid;
307 
308  if (block_size < sizeof(struct GNUNET_MessageHeader))
309  {
310  GNUNET_break_op (0);
311  memset (key,
312  0,
313  sizeof (*key));
314  return GNUNET_OK;
315  }
316  msg = block;
317  if (block_size != ntohs (msg->size))
318  {
319  GNUNET_break_op (0);
320  memset (key,
321  0,
322  sizeof (*key));
323  return GNUNET_OK;
324  }
325  hello = block;
326  memset (key,
327  0,
328  sizeof(*key));
329  pid = (struct GNUNET_PeerIdentity *) key;
330  if (GNUNET_OK !=
331  GNUNET_HELLO_get_id (hello,
332  pid))
333  {
334  GNUNET_break_op (0);
335  memset (key,
336  0,
337  sizeof (*key));
338  return GNUNET_OK;
339  }
340  return GNUNET_OK;
341  }
343  {
344  struct GNUNET_HELLO_Builder *b;
345  struct GNUNET_PeerIdentity pid;
346 
348  block_size);
349  if (NULL == b)
350  {
351  GNUNET_break (0);
352  memset (key,
353  0,
354  sizeof (*key));
355  return GNUNET_OK;
356  }
358  &pid,
359  NULL, NULL);
361  sizeof (pid),
362  key);
364  return GNUNET_OK;
365  }
366  default:
367  GNUNET_break (0);
368  return GNUNET_SYSERR;
369  }
370 }
371 
372 
376 void *
378 {
379  static enum GNUNET_BLOCK_Type types[] = {
382  GNUNET_BLOCK_TYPE_ANY /* end of list */
383  };
384  struct GNUNET_BLOCK_PluginFunctions *api;
385 
392  api->types = types;
393  return api;
394 }
395 
396 
400 void *
402 {
403  struct GNUNET_BLOCK_PluginFunctions *api = cls;
404 
405  GNUNET_free (api);
406  return NULL;
407 }
408 
409 
410 /* end of plugin_block_dht.c */
struct GNUNET_MessageHeader * msg
Definition: 005.c:2
GNUNET_BLOCK_Type
WARNING: This header is generated! In order to add DHT block types, you must register them in GANA,...
@ GNUNET_BLOCK_TYPE_LEGACY_HELLO
Legacy type of a block that contains a HELLO for a peer.
@ GNUNET_BLOCK_TYPE_ANY
Identifier for any block.
@ GNUNET_BLOCK_TYPE_DHT_HELLO
Type of a block that contains a DHT-NG HELLO for a peer.
struct GNUNET_HashCode key
The key used in the DHT.
static struct GNUNET_PeerIdentity pid
Identity of the peer we transmit to / connect to.
API for block plugins.
Helper library for handling HELLOs.
Helper library for handling HELLO URIs.
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.
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
struct GNUNET_HELLO_Builder * GNUNET_HELLO_builder_from_block(const void *block, size_t block_size)
Parse block into builder.
Definition: hello-uri.c:360
void GNUNET_HELLO_builder_free(struct GNUNET_HELLO_Builder *builder)
Release resources of a builder.
Definition: hello-uri.c:319
void GNUNET_HELLO_builder_iterate(const struct GNUNET_HELLO_Builder *builder, struct GNUNET_PeerIdentity *pid, GNUNET_HELLO_UriCallback uc, void *uc_cls)
Iterate over URIs in a builder.
Definition: hello-uri.c:822
int GNUNET_HELLO_get_id(const struct GNUNET_HELLO_Message *hello, struct GNUNET_PeerIdentity *peer)
Get the peer identity from a HELLO message.
Definition: hello.c:649
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_assert(cond)
Use this for fatal errors that cannot be handled.
#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 enum GNUNET_BLOCK_ReplyEvaluationResult block_plugin_dht_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.
#define BLOOMFILTER_K
Number of bits we set per entry in the bloomfilter.
static enum GNUNET_GenericReturnValue block_plugin_dht_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_dht_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_dht_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 enum GNUNET_GenericReturnValue block_plugin_dht_check_block(void *cls, enum GNUNET_BLOCK_Type type, const void *block, size_t block_size)
Function called to validate a block for storage.
void * libgnunet_plugin_block_dht_init(void *cls)
Entry point for the plugin.
void * libgnunet_plugin_block_dht_done(void *cls)
Exit point from the plugin.
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.
Context for building (or parsing) HELLO URIs.
Definition: hello-uri.c:184
A HELLO message is used to exchange information about transports with other peers.
A 512-bit hashcode.
Header for all communications.
uint16_t size
The length of the struct (in bytes, including the length field itself), in big-endian format.
The identity of the host (wraps the signing key of the peer).
enum GNUNET_TESTBED_UnderlayLinkModelType type
the type of this model