GNUnet 0.21.1
gnunet-service-dht_routing.c
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1/*
2 This file is part of GNUnet.
3 Copyright (C) 2011, 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
26#include "platform.h"
29#include "gnunet-service-dht.h"
31
32
37#define DHT_MAX_RECENT (1024 * 128)
38
39
45{
50
55
60
65
70 const void *xquery;
71
76
81
86};
87
88
93
98
99
104{
109
114
118 unsigned int get_path_length;
119
120};
121
122
132process (void *cls,
133 const struct GNUNET_HashCode *query_hash,
134 void *value)
135{
136 struct ProcessContext *pc = cls;
137 struct RecentRequest *rr = value;
139 unsigned int get_path_length;
140 struct GNUNET_DATACACHE_Block bdx = *pc->bd;
141
142 if ( (rr->type != GNUNET_BLOCK_TYPE_ANY) &&
143 (rr->type != pc->bd->type) )
144 return GNUNET_OK; /* type mismatch */
145 if (0 != (rr->options & GNUNET_DHT_RO_RECORD_ROUTE))
146 {
147 get_path_length = pc->get_path_length;
148 }
149 else
150 {
151 get_path_length = 0;
152 bdx.put_path_length = 0;
153 bdx.put_path = NULL;
154 }
155 if ( (0 == (rr->options & GNUNET_DHT_RO_FIND_APPROXIMATE)) &&
156 (0 != GNUNET_memcmp (query_hash,
157 &bdx.key)) )
158 {
160 "# Inexact matches discarded in exact search",
161 1,
162 GNUNET_NO);
163 return GNUNET_OK; /* exact search, but inexact match */
164 }
166 bdx.type,
167 rr->bg,
168 &bdx.key,
169 rr->xquery,
170 rr->xquery_size,
171 bdx.data,
172 bdx.data_size);
174 "Result for %s of type %d was evaluated as %d\n",
175 GNUNET_h2s (&bdx.key),
176 bdx.type,
177 eval);
179 {
180 /* If we do not know the block type, we still filter
181 exact duplicates by the block content */
182 struct GNUNET_HashCode chash;
183
185 bdx.data_size,
186 &chash);
187 if (GNUNET_YES ==
189 &chash))
191 else
193 }
194 switch (eval)
195 {
199 {
200 struct PeerInfo *pi;
201
203 "# Good REPLIES matched against routing table",
204 1,
205 GNUNET_NO);
207 if (NULL == pi)
208 {
209 /* peer disconnected in the meantime, drop reply */
211 "No matching peer for reply for key %s\n",
212 GNUNET_h2s (query_hash));
213 return GNUNET_OK;
214 }
216 &bdx,
217 query_hash,
218 get_path_length,
219 pc->get_path));
220 }
221 break;
224 "# Duplicate REPLIES matched against routing table",
225 1,
226 GNUNET_NO);
227 return GNUNET_OK;
230 "# Irrelevant REPLIES matched against routing table",
231 1,
232 GNUNET_NO);
233 return GNUNET_OK;
234 default:
235 GNUNET_break (0);
236 return GNUNET_OK;
237 }
238 return GNUNET_OK;
239}
240
241
254void
256 const struct GNUNET_HashCode *query_hash,
257 unsigned int get_path_length,
258 const struct GNUNET_DHT_PathElement *get_path)
259{
260 struct ProcessContext pc = {
261 .bd = bd,
262 .get_path = get_path,
263 .get_path_length = get_path_length
264 };
265
267 query_hash,
268 &process,
269 &pc);
270}
271
272
278static void
280{
281 struct RecentRequest *recent_req;
282
284 "# Old entries removed from routing table",
285 1,
286 GNUNET_NO);
288 GNUNET_assert (recent_req != NULL);
290 GNUNET_BLOCK_group_destroy (recent_req->bg);
293 &recent_req->key,
294 recent_req));
295 GNUNET_free (recent_req);
296}
297
298
311 const struct GNUNET_HashCode *key,
312 void *value)
313{
314 struct RecentRequest *in = cls;
315 struct RecentRequest *rr = value;
316
317 if ( (0 != GNUNET_memcmp (&in->peer,
318 &rr->peer)) ||
319 (in->type != rr->type) ||
320 (in->xquery_size != rr->xquery_size) ||
321 (0 != memcmp (in->xquery,
322 rr->xquery,
323 in->xquery_size) ) )
324 return GNUNET_OK;
327 rr->bg));
328 rr->bg = in->bg;
329 GNUNET_free (in);
330 return GNUNET_SYSERR;
331}
332
333
345void
348 struct GNUNET_BLOCK_Group *bg,
350 const struct GNUNET_HashCode *key,
351 const void *xquery,
352 size_t xquery_size)
353{
354 struct RecentRequest *recent_req;
355
359 "# Entries added to routing table",
360 1,
361 GNUNET_NO);
362 recent_req = GNUNET_malloc (sizeof(struct RecentRequest) + xquery_size);
363 recent_req->peer = *sender;
364 recent_req->key = *key;
365 recent_req->bg = bg;
366 recent_req->type = type;
367 recent_req->options = options;
368 recent_req->xquery = &recent_req[1];
369 GNUNET_memcpy (&recent_req[1],
370 xquery,
372 recent_req->xquery_size = xquery_size;
373 if (GNUNET_SYSERR ==
375 key,
377 recent_req))
378 {
380 "# DHT requests combined",
381 1,
382 GNUNET_NO);
383 return;
384 }
385 recent_req->heap_node
388 recent_req,
389 GNUNET_TIME_absolute_get ().abs_value_us);
392 key,
393 recent_req,
395}
396
397
401void
403{
406 GNUNET_NO);
407}
408
409
413void
415{
418 GNUNET_assert (0 ==
421 recent_heap = NULL;
422 GNUNET_assert (0 ==
425 recent_map = NULL;
426}
427
428
429/* end of gnunet-service-dht_routing.c */
struct GNUNET_GETOPT_CommandLineOption options[]
Definition: 002.c:5
struct GNUNET_HashCode key
The key used in the DHT.
static char * value
Value of the record to add/remove.
static uint32_t type
Type string converted to DNS type value.
static struct GNUNET_FS_PublishContext * pc
Handle to FS-publishing operation.
GNUnet DHT globals.
struct GNUNET_STATISTICS_Handle * GDS_stats
Handle for the statistics service.
struct GNUNET_BLOCK_Context * GDS_block_context
Our handle to the BLOCK library.
bool GDS_NEIGHBOURS_handle_reply(struct PeerInfo *pi, const struct GNUNET_DATACACHE_Block *bd, const struct GNUNET_HashCode *query_hash, unsigned int get_path_length, const struct GNUNET_DHT_PathElement *get_path)
Handle a reply (route to origin).
struct PeerInfo * GDS_NEIGHBOURS_lookup_peer(const struct GNUNET_PeerIdentity *target)
Lookup peer by peer's identity.
GNUnet DHT routing code.
static enum GNUNET_GenericReturnValue try_combine_recent(void *cls, const struct GNUNET_HashCode *key, void *value)
Try to combine multiple recent requests for the same value (if they come from the same peer).
static enum GNUNET_GenericReturnValue process(void *cls, const struct GNUNET_HashCode *query_hash, void *value)
Forward the result to the given peer if it matches the request.
void GDS_ROUTING_done()
Shutdown routing subsystem.
void GDS_ROUTING_add(const struct GNUNET_PeerIdentity *sender, enum GNUNET_BLOCK_Type type, struct GNUNET_BLOCK_Group *bg, enum GNUNET_DHT_RouteOption options, const struct GNUNET_HashCode *key, const void *xquery, size_t xquery_size)
Add a new entry to our routing table.
#define DHT_MAX_RECENT
Number of requests we track at most (for routing replies).
static void expire_oldest_entry(void)
Remove the oldest entry from the DHT routing table.
static struct GNUNET_CONTAINER_MultiHashMap * recent_map
Recently seen requests by key.
static struct GNUNET_CONTAINER_Heap * recent_heap
Recent requests by time inserted.
void GDS_ROUTING_process(const struct GNUNET_DATACACHE_Block *bd, const struct GNUNET_HashCode *query_hash, unsigned int get_path_length, const struct GNUNET_DHT_PathElement *get_path)
Handle a reply (route to origin).
void GDS_ROUTING_init()
Initialize routing subsystem.
GNUnet DHT tracking of requests for routing replies.
enum GNUNET_BLOCK_ReplyEvaluationResult GNUNET_BLOCK_check_reply(struct GNUNET_BLOCK_Context *ctx, 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 if a reply is good for a particular query.
Definition: block.c:337
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
GNUNET_BLOCK_ReplyEvaluationResult
Possible ways for how a block may relate to a query.
enum GNUNET_GenericReturnValue GNUNET_BLOCK_group_merge(struct GNUNET_BLOCK_Group *bg1, struct GNUNET_BLOCK_Group *bg2)
Try merging two block groups.
Definition: block.c:201
void GNUNET_BLOCK_group_destroy(struct GNUNET_BLOCK_Group *bg)
Destroy resources used by a block group.
Definition: block.c:192
@ 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.
@ GNUNET_BLOCK_REPLY_IRRELEVANT
Block does not match xquery (valid result, not relevant for the request)
GNUNET_DHT_RouteOption
Options for routing.
@ GNUNET_DHT_RO_RECORD_ROUTE
We should keep track of the route that the message took in the P2P network.
@ GNUNET_DHT_RO_FIND_APPROXIMATE
Approximate results are fine.
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
enum GNUNET_GenericReturnValue GNUNET_CONTAINER_multihashmap_remove(struct GNUNET_CONTAINER_MultiHashMap *map, const struct GNUNET_HashCode *key, const void *value)
Remove the given key-value pair from the map.
enum GNUNET_GenericReturnValue GNUNET_CONTAINER_multihashmap_put(struct GNUNET_CONTAINER_MultiHashMap *map, const struct GNUNET_HashCode *key, void *value, enum GNUNET_CONTAINER_MultiHashMapOption opt)
Store a key-value pair in the map.
unsigned int GNUNET_CONTAINER_multihashmap_size(const struct GNUNET_CONTAINER_MultiHashMap *map)
Get the number of key-value pairs in the map.
void GNUNET_CONTAINER_multihashmap_destroy(struct GNUNET_CONTAINER_MultiHashMap *map)
Destroy a hash map.
struct GNUNET_CONTAINER_MultiHashMap * GNUNET_CONTAINER_multihashmap_create(unsigned int len, int do_not_copy_keys)
Create a multi hash map.
enum GNUNET_GenericReturnValue GNUNET_CONTAINER_multihashmap_get_multiple(struct GNUNET_CONTAINER_MultiHashMap *map, const struct GNUNET_HashCode *key, GNUNET_CONTAINER_MultiHashMapIteratorCallback it, void *it_cls)
Iterate over all entries in the map that match a particular key.
@ GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE
Allow multiple values with the same key.
void * GNUNET_CONTAINER_heap_remove_node(struct GNUNET_CONTAINER_HeapNode *node)
Removes a node from the heap.
void * GNUNET_CONTAINER_heap_peek(const struct GNUNET_CONTAINER_Heap *heap)
Get element stored at the root of heap.
struct GNUNET_CONTAINER_HeapNode * GNUNET_CONTAINER_heap_insert(struct GNUNET_CONTAINER_Heap *heap, void *element, GNUNET_CONTAINER_HeapCostType cost)
Inserts a new element into the heap.
unsigned int GNUNET_CONTAINER_heap_get_size(const struct GNUNET_CONTAINER_Heap *heap)
Get the current size of the heap.
struct GNUNET_CONTAINER_Heap * GNUNET_CONTAINER_heap_create(enum GNUNET_CONTAINER_HeapOrder order)
Create a new heap.
void GNUNET_CONTAINER_heap_destroy(struct GNUNET_CONTAINER_Heap *heap)
Destroys the heap.
@ GNUNET_CONTAINER_HEAP_ORDER_MIN
Heap with the minimum cost at the root.
#define GNUNET_log(kind,...)
#define GNUNET_memcmp(a, b)
Compare memory in a and b, where both must be of the same pointer type.
#define GNUNET_memcpy(dst, src, n)
Call memcpy() but check for n being 0 first.
GNUNET_GenericReturnValue
Named constants for return values.
@ GNUNET_OK
@ GNUNET_YES
@ GNUNET_NO
@ GNUNET_SYSERR
#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.
const char * GNUNET_h2s(const struct GNUNET_HashCode *hc)
Convert a hash value to a string (for printing debug messages).
@ GNUNET_ERROR_TYPE_DEBUG
#define GNUNET_malloc(size)
Wrapper around malloc.
#define GNUNET_free(ptr)
Wrapper around free.
void GNUNET_STATISTICS_update(struct GNUNET_STATISTICS_Handle *handle, const char *name, int64_t delta, int make_persistent)
Set statistic value for the peer.
struct GNUNET_TIME_Absolute GNUNET_TIME_absolute_get(void)
Get the current time.
Definition: time.c:111
GNUNET_BLOCK_Type
WARNING: This header is generated! In order to add DHT block types, you must register them in GANA,...
@ GNUNET_BLOCK_TYPE_ANY
Identifier for any block.
Block group data.
Handle to a node in a heap.
Internal representation of the hash map.
Information about a block stored in the datacache.
const struct GNUNET_DHT_PathElement * put_path
PUT path taken by the block, array of peer identities.
enum GNUNET_BLOCK_Type type
Type of the block.
const void * data
Actual block data.
struct GNUNET_HashCode key
Key of the block.
size_t data_size
Number of bytes in data.
unsigned int put_path_length
Length of the put_path array.
A (signed) path tracking a block's flow through the DHT is represented by an array of path elements,...
A 512-bit hashcode.
The identity of the host (wraps the signing key of the peer).
Entry for a peer in a bucket.
Closure for the process() function.
const struct GNUNET_DHT_PathElement * get_path
Path of the reply.
const struct GNUNET_DATACACHE_Block * bd
Block data.
unsigned int get_path_length
Number of entries in get_path.
Information we keep about all recent GET requests so that we can route replies.
size_t xquery_size
Number of bytes in xquery.
enum GNUNET_BLOCK_Type type
Type of the requested block.
struct GNUNET_HashCode key
Key of this request.
struct GNUNET_BLOCK_Group * bg
Block group for filtering replies.
struct GNUNET_CONTAINER_HeapNode * heap_node
Position of this node in the min heap.
enum GNUNET_DHT_RouteOption options
Request options.
struct GNUNET_PeerIdentity peer
The peer this request was received from.
const void * xquery
extended query (see gnunet_block_lib.h).