GNUnet  0.10.x
gnunet-service-fs_cadet_client.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2012, 2013 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 
30 #include "platform.h"
31 #include "gnunet_constants.h"
32 #include "gnunet_util_lib.h"
33 #include "gnunet_cadet_service.h"
34 #include "gnunet_protocols.h"
35 #include "gnunet_applications.h"
36 #include "gnunet-service-fs.h"
39 
40 
44 #define CLIENT_RETRY_TIMEOUT \
45  GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS, 30)
46 
47 
51 struct CadetHandle;
52 
53 
62 
67 
71  struct CadetHandle *mh;
72 
77 
81  void *proc_cls;
82 
87 
92 
98 };
99 
100 
104 struct CadetHandle {
109 
114 
120 
125 
129  struct GNUNET_PeerIdentity target;
130 
137 
144 };
145 
146 
151 
157 
158 
159 /* ********************* client-side code ************************* */
160 
161 
167 static void
168 transmit_pending(void *cls);
169 
170 
180 static int
181 move_to_pending(void *cls, const struct GNUNET_HashCode *key, void *value)
182 {
183  struct CadetHandle *mh = cls;
184  struct GSF_CadetRequest *sr = value;
185 
187  GNUNET_YES ==
191  return GNUNET_YES;
192 }
193 
194 
203 static int
204 check_reply(void *cls, const struct CadetReplyMessage *srm)
205 {
206  /* We check later... */
207  return GNUNET_OK;
208 }
209 
210 
216 static void
217 reset_cadet_task(void *cls);
218 
219 
226 static void
228 {
229  if (NULL != mh->reset_task)
232 }
233 
234 
242  const void *data;
243 
248 
252  size_t data_size;
253 
258 
262  int found;
263 };
264 
265 
275 static int
276 process_reply(void *cls, const struct GNUNET_HashCode *key, void *value)
277 {
278  struct HandleReplyClosure *hrc = cls;
279  struct GSF_CadetRequest *sr = value;
280 
281  sr->proc(sr->proc_cls,
282  hrc->type,
283  hrc->expiration,
284  hrc->data_size,
285  hrc->data);
286  sr->proc = NULL;
288  hrc->found = GNUNET_YES;
289  return GNUNET_YES;
290 }
291 
292 
303 static int
304 free_waiting_entry(void *cls, const struct GNUNET_HashCode *key, void *value)
305 {
306  struct GSF_CadetRequest *sr = value;
307 
309  return GNUNET_YES;
310 }
311 
312 
320 static void
321 handle_reply(void *cls, const struct CadetReplyMessage *srm)
322 {
323  struct CadetHandle *mh = cls;
324  struct HandleReplyClosure hrc;
325  uint16_t msize;
326  enum GNUNET_BLOCK_Type type;
327  struct GNUNET_HashCode query;
328 
329  msize = ntohs(srm->header.size) - sizeof(struct CadetReplyMessage);
330  type = (enum GNUNET_BLOCK_Type)ntohl(srm->type);
331  if (GNUNET_YES !=
332  GNUNET_BLOCK_get_key(GSF_block_ctx, type, &srm[1], msize, &query))
333  {
334  GNUNET_break_op(0);
335  GNUNET_log(
337  "Received bogus reply of type %u with %u bytes via cadet from peer %s\n",
338  type,
339  msize,
340  GNUNET_i2s(&mh->target));
341  reset_cadet_async(mh);
342  return;
343  }
345  "Received reply `%s' via cadet from peer %s\n",
346  GNUNET_h2s(&query),
347  GNUNET_i2s(&mh->target));
350  gettext_noop("# replies received via cadet"),
351  1,
352  GNUNET_NO);
353  hrc.data = &srm[1];
354  hrc.data_size = msize;
356  hrc.type = type;
357  hrc.found = GNUNET_NO;
359  &query,
360  &process_reply,
361  &hrc);
362  if (GNUNET_NO == hrc.found)
363  {
365  gettext_noop(
366  "# replies received via cadet dropped"),
367  1,
368  GNUNET_NO);
369  }
370 }
371 
372 
380 static void
381 disconnect_cb(void *cls, const struct GNUNET_CADET_Channel *channel)
382 {
383  struct CadetHandle *mh = cls;
384  struct GSF_CadetRequest *sr;
385 
386  if (NULL == mh->channel)
387  return; /* being destroyed elsewhere */
388  GNUNET_assert(channel == mh->channel);
389  mh->channel = NULL;
390  while (NULL != (sr = mh->pending_head))
392  /* first remove `mh` from the `cadet_map`, so that if the
393  callback from `free_waiting_entry()` happens to re-issue
394  the request, we don't immediately have it back in the
395  `waiting_map`. */
397  &mh->target,
398  mh));
401  mh);
402  if (NULL != mh->timeout_task)
404  if (NULL != mh->reset_task)
408  GNUNET_free(mh);
409 }
410 
411 
426 static void
428  const struct GNUNET_CADET_Channel *channel,
429  int window_size)
430 {
431  /* FIXME: for flow control, implement? */
432 #if 0
433  /* Something like this instead of the GNUNET_MQ_notify_sent() in
434  transmit_pending() might be good (once the window change CB works...) */
435  if (0 < window_size) /* test needed? */
437 #endif
438 }
439 
440 
446 static void
448 {
450  "Resetting cadet channel to %s\n",
451  GNUNET_i2s(&mh->target));
452  if (NULL != mh->channel)
453  {
455  mh->channel = NULL;
456  }
458  {
459  struct GNUNET_MQ_MessageHandler handlers[] =
460  { GNUNET_MQ_hd_var_size(reply,
462  struct CadetReplyMessage,
463  mh),
465  struct GNUNET_HashCode port;
466 
469  &port);
470  mh->channel = GNUNET_CADET_channel_create(cadet_handle,
471  mh,
472  &mh->target,
473  &port,
475  &disconnect_cb,
476  handlers);
477  }
478  transmit_pending(mh);
479 }
480 
481 
487 static void
488 cadet_timeout(void *cls)
489 {
490  struct CadetHandle *mh = cls;
491  struct GNUNET_CADET_Channel *tun;
492 
494  "Timeout on cadet channel to %s\n",
495  GNUNET_i2s(&mh->target));
496  mh->timeout_task = NULL;
497  tun = mh->channel;
498  mh->channel = NULL;
499  if (NULL != tun)
501 }
502 
503 
509 static void
511 {
512  struct CadetHandle *mh = cls;
513 
514  mh->reset_task = NULL;
515  reset_cadet(mh);
516 }
517 
518 
524 static void
526 {
527  struct CadetHandle *mh = cls;
529  struct GSF_CadetRequest *sr;
530  struct GNUNET_MQ_Envelope *env;
531  struct CadetQueryMessage *sqm;
532 
533  if ((0 != GNUNET_MQ_get_length(mq)) || (NULL == (sr = mh->pending_head)))
534  return;
537  mh->waiting_map,
538  &sr->query,
539  sr,
543  "Sending query for %s via cadet to %s\n",
544  GNUNET_h2s(&sr->query),
545  GNUNET_i2s(&mh->target));
551  sqm->type = htonl(sr->type);
552  sqm->query = sr->query;
554  GNUNET_MQ_send(mq, env);
555 }
556 
557 
563 static struct CadetHandle *
565 {
566  struct CadetHandle *mh;
567 
568  mh = GNUNET_CONTAINER_multipeermap_get(cadet_map, target);
569  if (NULL != mh)
570  {
571  if (NULL != mh->timeout_task)
572  {
574  mh->timeout_task = NULL;
575  }
576  return mh;
577  }
579  "Creating cadet channel to %s\n",
580  GNUNET_i2s(target));
581  mh = GNUNET_new(struct CadetHandle);
582  mh->reset_task =
585  mh->target = *target;
588  cadet_map,
589  &mh->target,
590  mh,
592  {
593  struct GNUNET_MQ_MessageHandler handlers[] =
594  { GNUNET_MQ_hd_var_size(reply,
596  struct CadetReplyMessage,
597  mh),
599  struct GNUNET_HashCode port;
600 
603  &port);
604  mh->channel = GNUNET_CADET_channel_create(cadet_handle,
605  mh,
606  &mh->target,
607  &port,
609  &disconnect_cb,
610  handlers);
611  }
612  return mh;
613 }
614 
615 
626 struct GSF_CadetRequest *
628  const struct GNUNET_HashCode *query,
629  enum GNUNET_BLOCK_Type type,
631  void *proc_cls)
632 {
633  struct CadetHandle *mh;
634  struct GSF_CadetRequest *sr;
635 
637  "Preparing to send query for %s via cadet to %s\n",
638  GNUNET_h2s(query),
639  GNUNET_i2s(target));
640  mh = get_cadet(target);
641  sr = GNUNET_new(struct GSF_CadetRequest);
642  sr->mh = mh;
643  sr->proc = proc;
644  sr->proc_cls = proc_cls;
645  sr->type = type;
646  sr->query = *query;
648  transmit_pending(mh);
649  return sr;
650 }
651 
652 
659 void
661 {
662  struct CadetHandle *mh = sr->mh;
664 
665  p = sr->proc;
666  sr->proc = NULL;
667  if (NULL != p)
668  {
669  /* signal failure / cancellation to callback */
671  }
673  "Cancelled query for %s via cadet to %s\n",
674  GNUNET_h2s(&sr->query),
675  GNUNET_i2s(&sr->mh->target));
676  if (GNUNET_YES == sr->was_transmitted)
678  GNUNET_OK ==
680  else
682  GNUNET_free(sr);
684  (NULL == mh->pending_head))
686  &cadet_timeout,
687  mh);
688 }
689 
690 
699 int
701  const struct GNUNET_PeerIdentity *key,
702  void *value)
703 {
704  struct CadetHandle *mh = value;
705 
707  "Timeout on cadet channel to %s\n",
708  GNUNET_i2s(&mh->target));
709  if (NULL != mh->channel)
710  {
711  struct GNUNET_CADET_Channel *channel = mh->channel;
712 
713  mh->channel = NULL;
715  }
716  if (NULL != mh->reset_task)
717  {
719  mh->reset_task = NULL;
720  }
721  return GNUNET_YES;
722 }
723 
724 
725 /* end of gnunet-service-fs_cadet_client.c */
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
static void window_change_cb(void *cls, const struct GNUNET_CADET_Channel *channel, int window_size)
Function called whenever an MQ-channel&#39;s transmission window size changes.
#define GNUNET_MESSAGE_TYPE_FS_CADET_REPLY
P2P answer for content (one FS to another via a cadet).
struct GNUNET_TIME_Absolute expiration
Expiration time for the block.
struct GNUNET_CONTAINER_MultiPeerMap * cadet_map
Map from peer identities to &#39;struct CadetHandles&#39; with cadet channels to those peers.
Query from one peer, asking the other for CHK-data.
int found
Did we have a matching query?
static char * expiration
Credential TTL.
static int check_reply(void *cls, const struct CadetReplyMessage *srm)
Functions with this signature are called whenever a complete reply is received.
struct GNUNET_TIME_Absolute GNUNET_TIME_absolute_ntoh(struct GNUNET_TIME_AbsoluteNBO a)
Convert absolute time from network byte order.
Definition: time.c:671
#define GNUNET_TIME_UNIT_ZERO_ABS
Absolute time zero.
struct GSF_CadetRequest * GSF_cadet_query(const struct GNUNET_PeerIdentity *target, const struct GNUNET_HashCode *query, enum GNUNET_BLOCK_Type type, GSF_CadetReplyProcessor proc, void *proc_cls)
Look for a block by directly contacting a particular peer.
unsigned int GNUNET_CONTAINER_multihashmap_size(const struct GNUNET_CONTAINER_MultiHashMap *map)
Get the number of key-value pairs in the map.
#define GNUNET_CONTAINER_DLL_insert(head, tail, element)
Insert an element at the head of a DLL.
Any type of block, used as a wildcard when searching.
Opaque handle to the service.
Definition: cadet_api.c:38
GNUNET_BLOCK_Type
Blocks in the datastore and the datacache must have a unique type.
static void disconnect_cb(void *cls, const struct GNUNET_CADET_Channel *channel)
Function called by cadet when a client disconnects.
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
Handle for a cadet to another peer.
#define GNUNET_TIME_UNIT_SECONDS
One second.
struct GNUNET_MessageHeader header
Type is GNUNET_MESSAGE_TYPE_FS_CADET_REPLY.
void GNUNET_MQ_env_set_options(struct GNUNET_MQ_Envelope *env, enum GNUNET_MQ_PriorityPreferences pp)
Set application-specific options for this envelope.
Definition: mq.c:1002
static int process_reply(void *cls, const struct GNUNET_HashCode *key, void *value)
Iterator called on each entry in a waiting map to process a result.
#define GNUNET_MQ_msg(mvar, type)
Allocate a GNUNET_MQ_Envelope.
Definition: gnunet_mq_lib.h:67
static int move_to_pending(void *cls, const struct GNUNET_HashCode *key, void *value)
Iterator called on each entry in a waiting map to move it back to the pending list.
uint32_t type
Block type must be DBLOCK or IBLOCK.
struct GNUNET_STATISTICS_Handle * GSF_stats
Handle for reporting statistics.
int GNUNET_CONTAINER_multipeermap_remove(struct GNUNET_CONTAINER_MultiPeerMap *map, const struct GNUNET_PeerIdentity *key, const void *value)
Remove the given key-value pair from the map.
#define GNUNET_NO
Definition: gnunet_common.h:78
shared data structures of gnunet-service-fs.c
Opaque handle to a channel.
Definition: cadet_api.c:79
const char * GNUNET_h2s(const struct GNUNET_HashCode *hc)
Convert a hash value to a string (for printing debug messages).
#define GNUNET_OK
Named constants for return values.
Definition: gnunet_common.h:75
#define GNUNET_new(type)
Allocate a struct or union of the given type.
static void handle_reply(void *cls, const struct CadetReplyMessage *srm)
Functions with this signature are called whenever a complete reply is received.
uint16_t size
The length of the struct (in bytes, including the length field itself), in big-endian format...
void GNUNET_STATISTICS_update(struct GNUNET_STATISTICS_Handle *handle, const char *name, int64_t delta, int make_persistent)
Set statistic value for the peer.
Internal representation of the hash map.
struct GNUNET_HashCode query
Query to transmit to the other peer.
int GNUNET_BLOCK_get_key(struct GNUNET_BLOCK_Context *ctx, 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.
Definition: block.c:377
static void reset_cadet_async(struct CadetHandle *mh)
We had a serious error, tear down and re-create cadet from scratch, but do so asynchronously.
const void * data
Reply payload.
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:1237
Flag to indicate that high bandwidth is desired.
#define CLIENT_RETRY_TIMEOUT
After how long do we reset connections without replies?
static struct GNUNET_OS_Process * p
Helper process we started.
Definition: gnunet-qr.c:59
struct GNUNET_HashCode query
Query hash from CHK (hash of encrypted block).
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:772
static char * value
Value of the record to add/remove.
int was_transmitted
Did we transmit this request already? GNUNET_YES if we are in the &#39;waiting_map&#39;, GNUNET_NO if we are ...
#define GNUNET_MQ_hd_var_size(name, code, str, ctx)
#define GNUNET_break_op(cond)
Use this for assertion violations caused by other peers (i.e.
void GNUNET_CRYPTO_hash(const void *block, size_t size, struct GNUNET_HashCode *ret)
Compute hash of a given block.
Definition: crypto_hash.c:44
unsigned int GNUNET_MQ_get_length(struct GNUNET_MQ_Handle *mq)
Obtain the current length of the message queue.
Definition: mq.c:333
void GNUNET_CONTAINER_multihashmap_destroy(struct GNUNET_CONTAINER_MultiHashMap *map)
Destroy a hash map.
struct GSF_CadetRequest * next
DLL.
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:1264
struct GSF_CadetRequest * prev
DLL.
struct GNUNET_BLOCK_Context * GSF_block_ctx
Our block context.
static void reset_cadet_task(void *cls)
Task called when it is time to reset an cadet.
non-anonymous file-transfer
int 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.
void * proc_cls
Closure for proc.
Closure for handle_reply().
Internal representation of the hash map.
struct GNUNET_PeerIdentity target
Which peer does this cadet go to?
A 512-bit hashcode.
Message handler for a specific message type.
struct GNUNET_SCHEDULER_Task * timeout_task
Task to kill inactive cadets (we keep them around for a few seconds to give the application a chance ...
struct GNUNET_SCHEDULER_Task * reset_task
Task to reset cadets that had errors (asynchronously, as we may not be able to do it immediately duri...
There must only be one value per key; storing a value should fail if a value under the same key alrea...
Handle for a request that is going out via cadet API.
struct GNUNET_HashCode key
The key used in the DHT.
struct GNUNET_MQ_Envelope * env
Definition: 005.c:1
struct GNUNET_TIME_AbsoluteNBO expiration
Expiration time for the block.
indexing for the file-sharing service
int 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.
GSF_CadetReplyProcessor proc
Function to call with the result.
Allow multiple values with the same key.
Handle to a message queue.
Definition: mq.c:84
int GNUNET_CONTAINER_multipeermap_put(struct GNUNET_CONTAINER_MultiPeerMap *map, const struct GNUNET_PeerIdentity *key, void *value, enum GNUNET_CONTAINER_MultiHashMapOption opt)
Store a key-value pair in the map.
The identity of the host (wraps the signing key of the peer).
void GNUNET_CADET_receive_done(struct GNUNET_CADET_Channel *channel)
Send an ack on the channel to confirm the processing of a message.
Definition: cadet_api.c:951
int GNUNET_CONTAINER_multihashmap_get_multiple(struct GNUNET_CONTAINER_MultiHashMap *map, const struct GNUNET_HashCode *key, GNUNET_CONTAINER_MulitHashMapIteratorCallback it, void *it_cls)
Iterate over all entries in the map that match a particular key.
struct GNUNET_CADET_Channel * GNUNET_CADET_channel_create(struct GNUNET_CADET_Handle *h, void *channel_cls, const struct GNUNET_PeerIdentity *destination, const struct GNUNET_HashCode *port, GNUNET_CADET_WindowSizeEventHandler window_changes, GNUNET_CADET_DisconnectEventHandler disconnects, const struct GNUNET_MQ_MessageHandler *handlers)
Create a new channel towards a remote peer.
Definition: cadet_api.c:1065
struct GNUNET_CADET_Channel * channel
Channel to the other peer.
struct GSF_CadetRequest * pending_head
Head of DLL of pending requests on this cadet.
struct GSF_CadetRequest * pending_tail
Tail of DLL of pending requests on this cadet.
static void reset_cadet(struct CadetHandle *mh)
We had a serious error, tear down and re-create cadet from scratch.
void * GNUNET_CONTAINER_multipeermap_get(const struct GNUNET_CONTAINER_MultiPeerMap *map, const struct GNUNET_PeerIdentity *key)
Given a key find a value in the map matching the key.
struct GNUNET_MQ_Handle * mq
Definition: 003.c:5
#define GNUNET_MESSAGE_TYPE_FS_CADET_QUERY
P2P request for content (one FS to another via a cadet).
#define GNUNET_log(kind,...)
Entry in list of pending tasks.
Definition: scheduler.c:131
Flag to indicate that out-of-order delivery is OK.
static void cadet_timeout(void *cls)
Task called when it is time to destroy an inactive cadet channel.
static int free_waiting_entry(void *cls, const struct GNUNET_HashCode *key, void *value)
Iterator called on each entry in a waiting map to call the &#39;proc&#39; continuation and release associated...
struct GNUNET_CONTAINER_MultiHashMap * GNUNET_CONTAINER_multihashmap_create(unsigned int len, int do_not_copy_keys)
Create a multi hash map.
#define GNUNET_APPLICATION_PORT_FS_BLOCK_TRANSFER
Transfer of blocks for non-anonymmous file-sharing.
Flag to indicate that CORKing is acceptable.
Time for absolute times used by GNUnet, in microseconds.
#define GNUNET_YES
Definition: gnunet_common.h:77
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:351
uint32_t type
Block type must be DBLOCK or IBLOCK.
int GSF_cadet_release_clients(void *cls, const struct GNUNET_PeerIdentity *key, void *value)
Function called on each active cadets to shut them down.
static void transmit_pending(void *cls)
Transmit pending requests via the cadet.
struct GNUNET_CADET_Handle * cadet_handle
Cadet channel for creating outbound channels.
enum GNUNET_BLOCK_Type type
Type of the block.
struct CadetHandle * mh
Which cadet is this request associated with?
int GNUNET_CONTAINER_multihashmap_iterate(struct GNUNET_CONTAINER_MultiHashMap *map, GNUNET_CONTAINER_MulitHashMapIteratorCallback it, void *it_cls)
Iterate over all entries in the map.
size_t data_size
Number of bytes in data.
Reply to a CadetQueryMessage.
void GNUNET_CADET_channel_destroy(struct GNUNET_CADET_Channel *channel)
Destroy an existing channel.
Definition: cadet_api.c:900
const char * GNUNET_i2s(const struct GNUNET_PeerIdentity *pid)
Convert a peer identity to a string (for printing debug messages).
struct GNUNET_CONTAINER_MultiHashMap * waiting_map
Map from query to struct GSF_CadetRequests waiting for a reply.
enum GNUNET_BLOCK_Type type
Desired type for the reply.
#define GNUNET_MQ_handler_end()
End-marker for the handlers array.
void(* GSF_CadetReplyProcessor)(void *cls, enum GNUNET_BLOCK_Type type, struct GNUNET_TIME_Absolute expiration, size_t data_size, const void *data)
Function called with a reply from the cadet.
void GSF_cadet_query_cancel(struct GSF_CadetRequest *sr)
Cancel an active request; must not be called after &#39;proc&#39; was calld.
#define GNUNET_free(ptr)
Wrapper around free.
static struct CadetHandle * get_cadet(const struct GNUNET_PeerIdentity *target)
Get (or create) a cadet to talk to the given peer.
#define gettext_noop(String)
Definition: gettext.h:69
struct GNUNET_MQ_Handle * GNUNET_CADET_get_mq(const struct GNUNET_CADET_Channel *channel)
Obtain the message queue for a connected peer.
Definition: cadet_api.c:1116
void * GNUNET_SCHEDULER_cancel(struct GNUNET_SCHEDULER_Task *task)
Cancel the task with the specified identifier.
Definition: scheduler.c:956