GNUnet  0.10.x
peerinfo_api.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2001-2014 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_util_lib.h"
28 #include "gnunet_protocols.h"
29 #include "peerinfo.h"
30 
31 #define LOG(kind,...) GNUNET_log_from (kind, "peerinfo-api",__VA_ARGS__)
32 
33 
38 {
39 
44 
49 
54 
59 
63  void *callback_cls;
64 
69 
73  int have_peer;
74 
79 
80 };
81 
82 
87 {
92 
97 
102 
107 
112 
113 };
114 
115 
121 static void
123 
124 
132 struct GNUNET_PEERINFO_Handle *
134 {
135  struct GNUNET_PEERINFO_Handle *h;
136 
137  h = GNUNET_new (struct GNUNET_PEERINFO_Handle);
138  h->cfg = cfg;
139  reconnect (h);
140  if (NULL == h->mq)
141  {
142  GNUNET_free (h);
143  return NULL;
144  }
145  return h;
146 }
147 
148 
158 void
160 {
162 
163  while (NULL != (ic = h->ic_head))
164  {
166  h->ic_tail,
167  ic);
168  GNUNET_free (ic);
169  }
170  if (NULL != h->mq)
171  {
172  GNUNET_MQ_destroy (h->mq);
173  h->mq = NULL;
174  }
175  if (NULL != h->r_task)
176  {
178  h->r_task = NULL;
179  }
180  GNUNET_free (h);
181 }
182 
183 
189 static void
190 reconnect_task (void *cls)
191 {
192  struct GNUNET_PEERINFO_Handle *h = cls;
193 
194  h->r_task = NULL;
195  reconnect (h);
196 }
197 
198 
204 static void
206 {
208 
209  GNUNET_MQ_destroy (h->mq);
210  h->mq = NULL;
211  if (NULL != ic)
212  {
214  h->ic_tail,
215  ic);
216  if (NULL != ic->callback)
217  ic->callback (ic->callback_cls,
218  NULL,
219  NULL,
220  _("Failed to receive response from `PEERINFO' service."));
221  GNUNET_free (ic);
222  }
224  h);
225 }
226 
227 
235 static void
236 mq_error_handler (void *cls,
237  enum GNUNET_MQ_Error error)
238 {
239  struct GNUNET_PEERINFO_Handle *h = cls;
240 
241  do_reconnect (h);
242 }
243 
244 
245 
254 static int
255 check_info (void *cls,
256  const struct InfoMessage *im)
257 {
258  struct GNUNET_PEERINFO_Handle *h = cls;
260  uint16_t ms = ntohs (im->header.size) - sizeof (*im);
261 
262  if (0 != ntohl (im->reserved))
263  {
264  GNUNET_break (0);
265  return GNUNET_SYSERR;
266  }
267  if (NULL == ic)
268  {
269  /* didn't expect a response, bad */
270  GNUNET_break (0);
271  return GNUNET_SYSERR;
272  }
273  if ( (GNUNET_YES == ic->have_peer) &&
274  (0 != GNUNET_memcmp (&ic->peer,
275  &im->peer)) )
276  {
277  /* bogus message (from a different iteration call?); out of sequence! */
279  "Received HELLO for peer `%s', expected peer `%s'\n",
280  GNUNET_i2s (&im->peer),
281  GNUNET_i2s (&ic->peer));
282  GNUNET_break (0);
283  return GNUNET_SYSERR;
284  }
285  if (ms > sizeof (struct GNUNET_MessageHeader))
286  {
287  const struct GNUNET_HELLO_Message *hello;
288  struct GNUNET_PeerIdentity id;
289 
290  hello = (const struct GNUNET_HELLO_Message *) &im[1];
291  if (ms != GNUNET_HELLO_size (hello))
292  {
293  /* malformed message */
294  GNUNET_break (0);
295  return GNUNET_SYSERR;
296  }
297  if (GNUNET_OK !=
298  GNUNET_HELLO_get_id (hello,
299  &id))
300  {
301  /* malformed message */
302  GNUNET_break (0);
303  return GNUNET_SYSERR;
304  }
305  if (0 != GNUNET_memcmp (&im->peer,
306  &id))
307  {
308  /* malformed message */
309  GNUNET_break (0);
310  return GNUNET_SYSERR;
311  }
312  }
313  else if (0 != ms)
314  {
315  /* malformed message */
316  GNUNET_break (0);
317  return GNUNET_SYSERR;
318  }
319  return GNUNET_OK;
320 }
321 
322 
329 static void
330 handle_info (void *cls,
331  const struct InfoMessage *im)
332 {
333  struct GNUNET_PEERINFO_Handle *h = cls;
335  const struct GNUNET_HELLO_Message *hello = NULL;
336  uint16_t ms;
337 
338  ms = ntohs (im->header.size);
339  if (ms > sizeof (struct InfoMessage))
340  hello = (const struct GNUNET_HELLO_Message *) &im[1];
341  if (NULL != ic->callback)
342  ic->callback (ic->callback_cls,
343  &im->peer,
344  hello,
345  NULL);
346 }
347 
348 
354 static void
356 {
358  struct GNUNET_MQ_Envelope *env;
359  struct ListAllPeersMessage *lapm;
360  struct ListPeerMessage *lpm;
361 
362  if (NULL == ic)
363  {
364  GNUNET_break (0);
365  return;
366  }
367  if (NULL == h->mq)
368  {
369  GNUNET_break (0);
370  return;
371  }
372  if (GNUNET_NO == ic->have_peer)
373  {
375  "Requesting list of peers from PEERINFO service\n");
376  env = GNUNET_MQ_msg (lapm,
378  lapm->include_friend_only = htonl (ic->include_friend_only);
379  }
380  else
381  {
383  "Requesting information on peer `%s' from PEERINFO service\n",
384  GNUNET_i2s (&ic->peer));
385  env = GNUNET_MQ_msg (lpm,
387  lpm->include_friend_only = htonl (ic->include_friend_only);
388  lpm->peer = ic->peer;
389  }
390  GNUNET_MQ_send (h->mq,
391  env);
392 }
393 
394 
404 static void
406  const struct GNUNET_MessageHeader *msg)
407 {
408  struct GNUNET_PEERINFO_Handle *h = cls;
410 
411  if (NULL == ic)
412  {
413  /* didn't expect a response, reconnect */
414  GNUNET_break (0);
415  reconnect (h);
416  return;
417  }
419  "Received end of list of peers from PEERINFO service\n");
421  h->ic_tail,
422  ic);
423  if (NULL != h->ic_head)
424  send_ic_request (h);
425  if (NULL != ic->callback)
426  ic->callback (ic->callback_cls,
427  NULL,
428  NULL,
429  NULL);
430  GNUNET_free (ic);
431 }
432 
433 
439 static void
441 {
442  struct GNUNET_MQ_MessageHandler handlers[] = {
443  GNUNET_MQ_hd_var_size (info,
445  struct InfoMessage,
446  h),
447  GNUNET_MQ_hd_fixed_size (end_iteration,
449  struct GNUNET_MessageHeader,
450  h),
452  };
453 
454  if (NULL != h->r_task)
455  {
457  h->r_task = NULL;
458  }
459  if (NULL != h->mq)
460  {
461  GNUNET_MQ_destroy (h->mq);
462  h->mq = NULL;
463  }
464  h->mq = GNUNET_CLIENT_connect (h->cfg,
465  "peerinfo",
466  handlers,
468  h);
469  if (NULL != h->ic_head)
470  send_ic_request (h);
471 }
472 
473 
493  const struct GNUNET_PeerIdentity *peer,
495  void *callback_cls)
496 {
498 
500  ic->h = h;
502  ic->callback = callback;
504  if (NULL != peer)
505  {
506  ic->have_peer = GNUNET_YES;
507  ic->peer = *peer;
508  }
510  h->ic_tail,
511  ic);
512  if (h->ic_head == ic)
513  send_ic_request (h);
514  return ic;
515 }
516 
517 
523 void
525 {
526  struct GNUNET_PEERINFO_Handle *h = ic->h;
527 
528  ic->callback = NULL;
529  if (ic == h->ic_head)
530  return;
532  h->ic_tail,
533  ic);
534  GNUNET_free (ic);
535 }
536 
537 
556 struct GNUNET_MQ_Envelope *
558  const struct GNUNET_HELLO_Message *hello,
560  void *cont_cls)
561 {
562  struct GNUNET_MQ_Envelope *env;
563  struct GNUNET_PeerIdentity peer;
564 
565  if (NULL == h->mq)
566  return NULL;
568  GNUNET_HELLO_get_id (hello,
569  &peer));
571  "Adding peer `%s' to PEERINFO database\n",
572  GNUNET_i2s (&peer));
573  env = GNUNET_MQ_msg_copy ((const struct GNUNET_MessageHeader *) hello);
574  if (NULL != cont)
576  cont,
577  cont_cls);
578  GNUNET_MQ_send (h->mq,
579  env);
580  return env;
581 }
582 
583 
584 /* end of peerinfo_api.c */
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
uint32_t include_friend_only
Include friend only HELLOs and peers in callbacks.
Definition: peerinfo.h:77
#define GNUNET_MESSAGE_TYPE_PEERINFO_GET
Request update and listing of a peer.
struct GNUNET_MQ_Handle * mq
Connection to the service.
Definition: peerinfo_api.c:96
uint32_t include_friend_only
Include friend only HELLOs and peers in callbacks.
Definition: peerinfo.h:53
void(* GNUNET_PEERINFO_Processor)(void *cls, const struct GNUNET_PeerIdentity *peer, const struct GNUNET_HELLO_Message *hello, const char *err_msg)
Type of an iterator over the hosts.
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:668
struct GNUNET_MQ_Envelope * GNUNET_MQ_msg_copy(const struct GNUNET_MessageHeader *hdr)
Create a new envelope by copying an existing message.
Definition: mq.c:653
Handle to the peerinfo service.
Definition: peerinfo_api.c:86
A HELLO message is used to exchange information about transports with other peers.
struct GNUNET_MessageHeader * msg
Definition: 005.c:2
static void reconnect(struct GNUNET_PEERINFO_Handle *h)
Close the existing connection to PEERINFO and reconnect.
Definition: peerinfo_api.c:440
struct GNUNET_MQ_Handle * GNUNET_CLIENT_connect(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *service_name, const struct GNUNET_MQ_MessageHandler *handlers, GNUNET_MQ_ErrorHandler error_handler, void *error_handler_cls)
Create a message queue to connect to a GNUnet service.
Definition: client.c:901
struct GNUNET_PEERINFO_Handle * GNUNET_PEERINFO_connect(const struct GNUNET_CONFIGURATION_Handle *cfg)
Connect to the peerinfo service.
Definition: peerinfo_api.c:133
struct GNUNET_PeerIdentity peer
Restrict to peers with this identity (optional field, check header.size!).
Definition: peerinfo.h:59
GNUNET_MQ_Error
Error codes for the queue.
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
static void send_ic_request(struct GNUNET_PEERINFO_Handle *h)
Send the next IC request at the head of the queue.
Definition: peerinfo_api.c:355
Message used to inform the client about a particular peer; this message is optionally followed by a H...
Definition: peerinfo.h:107
struct GNUNET_PEERINFO_IteratorContext * ic_tail
Tail of iterator DLL.
Definition: peerinfo_api.c:106
const struct GNUNET_CONFIGURATION_Handle * cfg
Our configuration.
Definition: peerinfo_api.c:91
struct GNUNET_PEERINFO_IteratorContext * ic_head
Head of iterator DLL.
Definition: peerinfo_api.c:101
#define GNUNET_MQ_hd_fixed_size(name, code, str, ctx)
#define GNUNET_MQ_msg(mvar, type)
Allocate a GNUNET_MQ_Envelope.
Definition: gnunet_mq_lib.h:67
#define GNUNET_NO
Definition: gnunet_common.h:81
#define GNUNET_OK
Named constants for return values.
Definition: gnunet_common.h:78
#define GNUNET_new(type)
Allocate a struct or union of the given type.
uint16_t size
The length of the struct (in bytes, including the length field itself), in big-endian format...
#define LOG(kind,...)
Definition: peerinfo_api.c:31
Context for an iteration request.
Definition: peerinfo_api.c:37
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur...
void(* GNUNET_SCHEDULER_TaskCallback)(void *cls)
Signature of the main function of a task.
static void do_reconnect(struct GNUNET_PEERINFO_Handle *h)
We encountered an error, reconnect to the PEERINFO service.
Definition: peerinfo_api.c:205
#define _(String)
GNU gettext support macro.
Definition: platform.h:208
struct GNUNET_PeerIdentity peer
About which peer are we talking here?
Definition: peerinfo.h:123
struct GNUNET_PEERINFO_IteratorContext * GNUNET_PEERINFO_iterate(struct GNUNET_PEERINFO_Handle *h, int include_friend_only, const struct GNUNET_PeerIdentity *peer, GNUNET_PEERINFO_Processor callback, void *callback_cls)
Call a method for each known matching host.
Definition: peerinfo_api.c:491
void GNUNET_PEERINFO_iterate_cancel(struct GNUNET_PEERINFO_IteratorContext *ic)
Cancel an iteration over peer information.
Definition: peerinfo_api.c:524
void GNUNET_MQ_notify_sent(struct GNUNET_MQ_Envelope *ev, GNUNET_SCHEDULER_TaskCallback cb, void *cb_cls)
Call a callback once the envelope has been sent, that is, sending it can not be canceled anymore...
Definition: mq.c:774
struct GNUNET_PEERINFO_IteratorContext * next
Kept in a DLL.
Definition: peerinfo_api.c:43
uint32_t reserved
Always zero.
Definition: peerinfo.h:118
#define GNUNET_MQ_hd_var_size(name, code, str, ctx)
struct GNUNET_SCHEDULER_Task * GNUNET_SCHEDULER_add_now(GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
Schedule a new task to be run as soon as possible.
Definition: scheduler.c:1273
static void mq_error_handler(void *cls, enum GNUNET_MQ_Error error)
We got a disconnect after asking regex to do the announcement.
Definition: peerinfo_api.c:236
void * callback_cls
Closure for callback.
Definition: peerinfo_api.c:63
static void handle_end_iteration(void *cls, const struct GNUNET_MessageHeader *msg)
Type of a function to call when we receive a message from the service.
Definition: peerinfo_api.c:405
struct GNUNET_MessageHeader header
Type will be GNUNET_MESSAGE_TYPE_PEERINFO_INFO.
Definition: peerinfo.h:113
struct GNUNET_MQ_Envelope * GNUNET_PEERINFO_add_peer(struct GNUNET_PEERINFO_Handle *h, const struct GNUNET_HELLO_Message *hello, GNUNET_SCHEDULER_TaskCallback cont, void *cont_cls)
Add a host to the persistent list.
Definition: peerinfo_api.c:557
static void reconnect_task(void *cls)
Task scheduled to re-try connecting to the peerinfo service.
Definition: peerinfo_api.c:190
Message handler for a specific message type.
struct GNUNET_SCHEDULER_Task * r_task
ID for a reconnect task.
Definition: peerinfo_api.c:111
static struct GNUNET_CONFIGURATION_Handle * cfg
Our configuration.
Definition: gnunet-arm.c:104
#define GNUNET_SYSERR
Definition: gnunet_common.h:79
common internal definitions for peerinfo service
struct GNUNET_MQ_Envelope * env
Definition: 005.c:1
#define GNUNET_CONTAINER_DLL_insert_tail(head, tail, element)
Insert an element at the tail of a DLL.
#define GNUNET_MESSAGE_TYPE_PEERINFO_INFO
Information about one of the peers.
#define GNUNET_memcmp(a, b)
Compare memory in a and b, where both must be of the same pointer type.
Handle to a message queue.
Definition: mq.c:85
The identity of the host (wraps the signing key of the peer).
configuration data
Definition: configuration.c:85
GNUNET_PEERINFO_Processor callback
Function to call with the results.
Definition: peerinfo_api.c:58
static int check_info(void *cls, const struct InfoMessage *im)
Function called when we receive an info message.
Definition: peerinfo_api.c:255
static void handle_info(void *cls, const struct InfoMessage *im)
Handle info message.
Definition: peerinfo_api.c:330
Entry in list of pending tasks.
Definition: scheduler.c:134
Message requesting a listing of all peers, restricted to the specified peer identity.
Definition: peerinfo.h:67
int include_friend_only
Only include friends in reply?
Definition: peerinfo_api.c:78
uint16_t GNUNET_HELLO_size(const struct GNUNET_HELLO_Message *hello)
Return the size of the given HELLO message.
Definition: hello.c:649
Message requesting a listing of peers, restricted to the specified peer identity. ...
Definition: peerinfo.h:42
void GNUNET_PEERINFO_disconnect(struct GNUNET_PEERINFO_Handle *h)
Disconnect from the peerinfo service.
Definition: peerinfo_api.c:159
#define GNUNET_MESSAGE_TYPE_PEERINFO_GET_ALL
Request update and listing of all peers.
Header for all communications.
struct GNUNET_PeerIdentity peer
Peer we are interested in (only valid if iteration was restricted to one peer).
Definition: peerinfo_api.c:68
void GNUNET_MQ_destroy(struct GNUNET_MQ_Handle *mq)
Destroy the message queue.
Definition: mq.c:824
#define GNUNET_YES
Definition: gnunet_common.h:80
void GNUNET_MQ_send(struct GNUNET_MQ_Handle *mq, struct GNUNET_MQ_Envelope *ev)
Send a message with the given message queue.
Definition: mq.c:353
#define GNUNET_MESSAGE_TYPE_PEERINFO_INFO_END
End of information about other peers.
struct GNUNET_PEERINFO_Handle * h
Handle to the PEERINFO service.
Definition: peerinfo_api.c:53
const char * GNUNET_i2s(const struct GNUNET_PeerIdentity *pid)
Convert a peer identity to a string (for printing debug messages).
#define GNUNET_MQ_handler_end()
End-marker for the handlers array.
struct GNUNET_PEERINFO_IteratorContext * prev
Kept in a DLL.
Definition: peerinfo_api.c:48
#define GNUNET_free(ptr)
Wrapper around free.
void * GNUNET_SCHEDULER_cancel(struct GNUNET_SCHEDULER_Task *task)
Cancel the task with the specified identifier.
Definition: scheduler.c:965