GNUnet  0.20.0
gnunet-service-cadet_dht.c
Go to the documentation of this file.
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  */
27 #include "platform.h"
28 #include "gnunet_util_lib.h"
29 #include "gnunet_dht_service.h"
31 #include "gnunet-service-cadet.h"
36 
43 #define STARTUP_DELAY GNUNET_TIME_relative_multiply ( \
44  GNUNET_TIME_UNIT_MILLISECONDS, 500)
45 
51 #define CHANGE_DELAY GNUNET_TIME_relative_multiply ( \
52  GNUNET_TIME_UNIT_MILLISECONDS, 100)
53 
54 
55 #define LOG(level, ...) GNUNET_log_from (level, "cadet-dht", __VA_ARGS__)
56 
57 
59 {
64 };
65 
66 
71 
76 
80 static unsigned long long dht_replication_level;
81 
86 
91 
92 
110 static void
112  const struct GNUNET_HashCode *key,
113  const struct GNUNET_PeerIdentity *trunc_peer,
114  const struct GNUNET_DHT_PathElement *get_path,
115  unsigned int get_path_length,
116  const struct GNUNET_DHT_PathElement *put_path,
117  unsigned int put_path_length,
118  enum GNUNET_BLOCK_Type type,
119  size_t size,
120  const void *data)
121 {
122  const struct GNUNET_HELLO_Message *hello = data;
123 
124  (void) trunc_peer;
125  GCPP_try_path_from_dht (get_path,
126  get_path_length,
127  put_path,
128  put_path_length);
129  if ((size >= sizeof(struct GNUNET_HELLO_Message)) &&
130  (ntohs (hello->header.size) == size) &&
131  (size == GNUNET_HELLO_size (hello)))
132  {
133  struct CadetPeer *peer;
134 
135  peer = GCP_get (&put_path[0].pred,
136  GNUNET_YES);
138  "Got HELLO for %s\n",
139  GCP_2s (peer));
141  hello);
142  }
143 }
144 
145 
151 static void
152 announce_id (void *cls)
153 {
154  struct GNUNET_HashCode phash;
155  const struct GNUNET_HELLO_Message *hello;
156  size_t size;
158  struct GNUNET_TIME_Relative next_put;
159 
160  hello = GCH_get_mine ();
161  size = (NULL != hello) ? GNUNET_HELLO_size (hello) : 0;
162  if (0 == size)
163  {
167  }
168  else
169  {
172  }
173 
174  /* Call again in id_announce_time, unless HELLO expires first,
175  * but wait at least 1s. */
176  next_put
178  next_put
179  = GNUNET_TIME_relative_min (next_put,
181  next_put
182  = GNUNET_TIME_relative_max (next_put,
185  = GNUNET_SCHEDULER_add_delayed (next_put,
186  &announce_id,
187  cls);
189  "# DHT announce",
190  1,
191  GNUNET_NO);
192  memset (&phash,
193  0,
194  sizeof(phash));
195  GNUNET_memcpy (&phash,
196  &my_full_id,
197  sizeof(my_full_id));
199  "Announcing my HELLO (%lu bytes) in the DHT\n",
200  (unsigned long) size);
201  GNUNET_DHT_put (dht_handle, /* DHT handle */
202  &phash, /* Key to use */
203  dht_replication_level, /* Replication level */
205  | GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE, /* DHT options */
206  GNUNET_BLOCK_TYPE_LEGACY_HELLO, /* Block type */
207  size, /* Size of the data */
208  (const char *) hello, /* Data itself */
209  expiration, /* Data expiration */
210  NULL, /* Continuation */
211  NULL); /* Continuation closure */
212 }
213 
214 
215 void
217 {
218  if (NULL == announce_id_task)
219  return; /* too early */
223  &announce_id,
224  NULL);
225 }
226 
227 
228 void
230 {
231  if (GNUNET_OK !=
233  "CADET",
234  "DHT_REPLICATION_LEVEL",
236  {
238  "CADET",
239  "DHT_REPLICATION_LEVEL",
240  "USING DEFAULT");
242  }
243 
244  if (GNUNET_OK !=
246  "CADET",
247  "ID_ANNOUNCE_TIME",
249  {
251  "CADET",
252  "ID_ANNOUNCE_TIME",
253  "MISSING");
255  return;
256  }
257 
259  64);
260  GNUNET_break (NULL != dht_handle);
263  &announce_id,
264  NULL);
265 }
266 
267 
268 void
270 {
271  if (NULL != dht_handle)
272  {
274  dht_handle = NULL;
275  }
276  if (NULL != announce_id_task)
277  {
279  announce_id_task = NULL;
280  }
281 }
282 
283 
284 struct GCD_search_handle *
286 {
287  struct GNUNET_HashCode phash;
288  struct GCD_search_handle *h;
289 
291  "# DHT search",
292  1,
293  GNUNET_NO);
294  memset (&phash,
295  0,
296  sizeof(phash));
297  GNUNET_memcpy (&phash,
298  peer_id,
299  sizeof(*peer_id));
300 
301  h = GNUNET_new (struct GCD_search_handle);
302  h->dhtget = GNUNET_DHT_get_start (dht_handle, /* handle */
304  &phash, /* key to search */
305  dht_replication_level, /* replication level */
308  NULL, /* xquery */
309  0, /* xquery bits */
311  h);
313  "Starting DHT GET for peer %s (%p)\n",
315  h);
316  return h;
317 }
318 
319 
320 void
322 {
324  "Stopping DHT GET %p\n",
325  h);
326  GNUNET_DHT_get_stop (h->dhtget);
327  GNUNET_free (h);
328 }
329 
330 
331 /* end of gnunet-service-cadet_dht.c */
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.
static char * expiration
Credential TTL.
Definition: gnunet-abd.c:96
static struct GNUNET_ARM_Handle * h
Connection with ARM.
Definition: gnunet-arm.c:99
static char * peer_id
Option –peer.
Definition: gnunet-cadet.c:42
struct GNUNET_HashCode key
The key used in the DHT.
uint32_t data
The data value.
struct GNUNET_PeerIdentity my_full_id
Local peer own ID.
struct GNUNET_STATISTICS_Handle * stats
Handle to the statistics service.
Information we track per peer.
static struct GNUNET_SCHEDULER_Task * announce_id_task
Task to periodically announce itself in the network.
static struct GNUNET_TIME_Relative id_announce_time
How often to PUT own ID in the DHT.
#define CHANGE_DELAY
How long do we wait after we get an updated HELLO before publishing? Allows for the HELLO to be updat...
struct GCD_search_handle * GCD_search(const struct GNUNET_PeerIdentity *peer_id)
Search DHT for paths to peeR_id.
static unsigned long long dht_replication_level
DHT replication level, see DHT API: GNUNET_DHT_get_start(), GNUNET_DHT_put().
static struct GNUNET_TIME_Relative announce_delay
Delay for the next ID announce.
void GCD_search_stop(struct GCD_search_handle *h)
Stop DHT search started with GCD_search().
static void announce_id(void *cls)
Periodically announce self id in the DHT.
static struct GNUNET_DHT_Handle * dht_handle
Handle to use DHT.
void GCD_hello_update()
Function called by the HELLO subsystem whenever OUR hello changes.
void GCD_init(const struct GNUNET_CONFIGURATION_Handle *c)
Initialize the DHT subsystem.
#define STARTUP_DELAY
How long do we wait before first announcing our presence to the DHT.
#define LOG(level,...)
static void dht_get_id_handler(void *cls, struct GNUNET_TIME_Absolute exp, const struct GNUNET_HashCode *key, const struct GNUNET_PeerIdentity *trunc_peer, const struct GNUNET_DHT_PathElement *get_path, unsigned int get_path_length, const struct GNUNET_DHT_PathElement *put_path, unsigned int put_path_length, enum GNUNET_BLOCK_Type type, size_t size, const void *data)
Function to process paths received for a new peer addition.
void GCD_shutdown(void)
Shut down the DHT subsystem.
cadet service; dealing with DHT requests and results
const struct GNUNET_HELLO_Message * GCH_get_mine(void)
Get own hello message.
cadet service; dealing with hello messages
void GCPP_try_path_from_dht(const struct GNUNET_DHT_PathElement *get_path, unsigned int get_path_length, const struct GNUNET_DHT_PathElement *put_path, unsigned int put_path_length)
Create a peer path based on the result of a DHT lookup.
void GCP_set_hello(struct CadetPeer *cp, const struct GNUNET_HELLO_Message *hello)
We got a HELLO for a cp, remember it, and possibly trigger adequate actions (like trying to connect).
struct CadetPeer * GCP_get(const struct GNUNET_PeerIdentity *peer_id, int create)
Retrieve the CadetPeer structure associated with the peer.
const char * GCP_2s(const struct CadetPeer *cp)
Get the static string for a peer ID.
Information we track per peer.
API to the DHT service.
API to create, modify and access statistics.
enum GNUNET_GenericReturnValue 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.
enum GNUNET_GenericReturnValue 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.
void GNUNET_DHT_get_stop(struct GNUNET_DHT_GetHandle *get_handle)
Stop async DHT-get.
Definition: dht_api.c:1237
struct GNUNET_DHT_Handle * GNUNET_DHT_connect(const struct GNUNET_CONFIGURATION_Handle *cfg, unsigned int ht_len)
Initialize the connection with the DHT service.
Definition: dht_api.c:1039
struct GNUNET_DHT_PutHandle * GNUNET_DHT_put(struct GNUNET_DHT_Handle *handle, const struct GNUNET_HashCode *key, uint32_t desired_replication_level, enum GNUNET_DHT_RouteOption options, enum GNUNET_BLOCK_Type type, size_t size, const void *data, struct GNUNET_TIME_Absolute exp, GNUNET_SCHEDULER_TaskCallback cont, void *cont_cls)
Perform a PUT operation storing data in the DHT.
Definition: dht_api.c:1090
void GNUNET_DHT_disconnect(struct GNUNET_DHT_Handle *handle)
Shutdown connection with the DHT service.
Definition: dht_api.c:1062
struct GNUNET_DHT_GetHandle * GNUNET_DHT_get_start(struct GNUNET_DHT_Handle *handle, enum GNUNET_BLOCK_Type type, const struct GNUNET_HashCode *key, uint32_t desired_replication_level, enum GNUNET_DHT_RouteOption options, const void *xquery, size_t xquery_size, GNUNET_DHT_GetIterator iter, void *iter_cls)
Perform an asynchronous GET operation on the DHT identified.
Definition: dht_api.c:1164
@ GNUNET_DHT_RO_RECORD_ROUTE
We should keep track of the route that the message took in the P2P network.
@ GNUNET_DHT_RO_DEMULTIPLEX_EVERYWHERE
Each peer along the way should process the request (otherwise only peers locally closest to the key w...
uint16_t GNUNET_HELLO_size(const struct GNUNET_HELLO_Message *hello)
Return the size of the given HELLO message.
Definition: hello.c:630
struct GNUNET_TIME_Absolute GNUNET_HELLO_get_last_expiration(const struct GNUNET_HELLO_Message *msg)
When does the last address in the given HELLO expire?
Definition: hello.c:870
#define GNUNET_memcpy(dst, src, n)
Call memcpy() but check for n being 0 first.
@ GNUNET_OK
@ GNUNET_YES
@ GNUNET_NO
const char * GNUNET_i2s(const struct GNUNET_PeerIdentity *pid)
Convert a peer identity to a string (for printing debug messages).
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur.
void GNUNET_log_config_invalid(enum GNUNET_ErrorType kind, const char *section, const char *option, const char *required)
Log error message about invalid configuration option value.
@ GNUNET_ERROR_TYPE_WARNING
@ GNUNET_ERROR_TYPE_ERROR
@ GNUNET_ERROR_TYPE_DEBUG
#define GNUNET_new(type)
Allocate a struct or union of the given type.
#define GNUNET_free(ptr)
Wrapper around free.
void GNUNET_SCHEDULER_shutdown(void)
Request the shutdown of a scheduler.
Definition: scheduler.c:562
void * GNUNET_SCHEDULER_cancel(struct GNUNET_SCHEDULER_Task *task)
Cancel the task with the specified identifier.
Definition: scheduler.c:975
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_delayed(struct GNUNET_TIME_Relative delay, GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run with a specified delay.
Definition: scheduler.c:1272
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_Relative GNUNET_TIME_relative_min(struct GNUNET_TIME_Relative t1, struct GNUNET_TIME_Relative t2)
Return the minimum of two relative time values.
Definition: time.c:343
struct GNUNET_TIME_Relative GNUNET_TIME_relative_max(struct GNUNET_TIME_Relative t1, struct GNUNET_TIME_Relative t2)
Return the maximum of two relative time values.
Definition: time.c:351
#define GNUNET_TIME_UNIT_SECONDS
One second.
struct GNUNET_TIME_Relative GNUNET_TIME_absolute_get_remaining(struct GNUNET_TIME_Absolute future)
Given a timestamp in the future, how much time remains until then?
Definition: time.c:405
struct GNUNET_TIME_Absolute GNUNET_TIME_absolute_get(void)
Get the current time.
Definition: time.c:111
struct GNUNET_TIME_Absolute GNUNET_TIME_absolute_add(struct GNUNET_TIME_Absolute start, struct GNUNET_TIME_Relative duration)
Add a given relative duration to the given start time.
Definition: time.c:450
#define GNUNET_TIME_STD_BACKOFF(r)
Perform our standard exponential back-off calculation, starting at 1 ms and then going by a factor of...
static unsigned int size
Size of the "table".
Definition: peer.c:68
Peer description.
struct GNUNET_HELLO_Message * hello
Hello message of the peer.
struct GNUNET_DHT_GetHandle * dhtget
DHT_GET handle.
Handle to a GET request.
Definition: dht_api.c:81
Connection to the DHT service.
Definition: dht_api.c:237
A (signed) path tracking a block's flow through the DHT is represented by an array of path elements,...
A HELLO message is used to exchange information about transports with other peers.
struct GNUNET_MessageHeader header
Type will be GNUNET_MESSAGE_TYPE_HELLO.
A 512-bit hashcode.
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).
Entry in list of pending tasks.
Definition: scheduler.c:136
Time for absolute times used by GNUnet, in microseconds.
Time for relative time used by GNUnet, in microseconds.
enum GNUNET_TESTBED_UnderlayLinkModelType type
the type of this model
struct GNUNET_TESTBED_Peer * peer
The peer associated with this model.