GNUnet  0.11.x
gnunet-service-fs_cadet_server.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2012, 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  */
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 
43 #define IDLE_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MINUTES, 2)
44 
45 
50 {
55 
60 
64  size_t msize;
65 };
66 
67 
71 struct CadetClient
72 {
76  struct CadetClient *next;
77 
81  struct CadetClient *prev;
82 
87 
92 
97 
102 
107 
112 
116  size_t reply_size;
117 };
118 
119 
124 
128 static struct CadetClient *sc_head;
129 
133 static struct CadetClient *sc_tail;
134 
138 static unsigned int sc_count;
139 
143 static unsigned long long sc_count_max;
144 
145 
151 static void
153 {
154  struct CadetClient *sc = cls;
155  struct GNUNET_CADET_Channel *tun;
156 
157  sc->timeout_task = NULL;
158  tun = sc->channel;
159  sc->channel = NULL;
161  "Timeout for inactive cadet client %p\n",
162  sc);
164 }
165 
166 
172 static void
174 {
175  if (NULL != sc->timeout_task)
179  sc);
180 }
181 
182 
189 static void
190 continue_writing (void *cls)
191 {
192  struct CadetClient *sc = cls;
193  struct GNUNET_MQ_Handle *mq;
194 
195  mq = GNUNET_CADET_get_mq (sc->channel);
196  if (0 != GNUNET_MQ_get_length (mq))
197  {
199  "Write pending, waiting for it to complete\n");
200  return;
201  }
204  "Finished processing cadet request from client %p, ready to receive the next one\n",
205  sc);
207 }
208 
209 
225 static void
227  const struct GNUNET_HashCode *key,
228  size_t size,
229  const void *data,
230  enum GNUNET_BLOCK_Type type,
231  uint32_t priority,
232  uint32_t anonymity,
233  uint32_t replication,
235  uint64_t uid)
236 {
237  struct CadetClient *sc = cls;
238  size_t msize = size + sizeof(struct CadetReplyMessage);
239  struct GNUNET_MQ_Envelope *env;
240  struct CadetReplyMessage *srm;
241 
242  sc->qe = NULL;
243  if (NULL == data)
244  {
245  /* no result, this should not really happen, as for
246  non-anonymous routing only peers that HAVE the
247  answers should be queried; OTOH, this is not a
248  hard error as we might have had the answer in the
249  past and the user might have unindexed it. Hence
250  we log at level "INFO" for now. */if (NULL == key)
251  {
253  "Have no answer and the query was NULL\n");
254  }
255  else
256  {
258  "Have no answer for query `%s'\n",
259  GNUNET_h2s (key));
260  }
262  gettext_noop (
263  "# queries received via CADET not answered"),
264  1,
265  GNUNET_NO);
266  continue_writing (sc);
267  return;
268  }
269  if (GNUNET_BLOCK_TYPE_FS_ONDEMAND == type)
270  {
272  "Performing on-demand encoding for query %s\n",
273  GNUNET_h2s (key));
274  if (GNUNET_OK !=
276  size,
277  data,
278  type,
279  priority,
280  anonymity,
281  replication,
282  expiration,
283  uid,
285  sc))
286  {
288  "On-demand encoding request failed\n");
289  continue_writing (sc);
290  }
291  return;
292  }
293  if (msize > GNUNET_MAX_MESSAGE_SIZE)
294  {
295  GNUNET_break (0);
296  continue_writing (sc);
297  return;
298  }
301  "Starting transmission of %u byte reply of type %d for query `%s' via cadet to %p\n",
302  (unsigned int) size,
303  (unsigned int) type,
304  GNUNET_h2s (key),
305  sc);
306  env = GNUNET_MQ_msg_extra (srm,
307  size,
309  srm->type = htonl (type);
310  srm->expiration = GNUNET_TIME_absolute_hton (expiration);
311  GNUNET_memcpy (&srm[1],
312  data,
313  size);
316  sc);
318  gettext_noop ("# Blocks transferred via cadet"),
319  1,
320  GNUNET_NO);
322  env);
323 }
324 
325 
333 static void
334 handle_request (void *cls,
335  const struct CadetQueryMessage *sqm)
336 {
337  struct CadetClient *sc = cls;
338 
340  "Received query for `%s' via cadet from client %p\n",
341  GNUNET_h2s (&sqm->query),
342  sc);
344  gettext_noop ("# queries received via cadet"),
345  1,
346  GNUNET_NO);
349  0 /* next_uid */,
350  false /* random */,
351  &sqm->query,
352  ntohl (sqm->type),
353  0 /* priority */,
356  sc);
357  if (NULL == sc->qe)
358  {
360  "Queueing request with datastore failed (queue full?)\n");
361  continue_writing (sc);
362  }
363 }
364 
365 
375 static void *
376 connect_cb (void *cls,
378  const struct GNUNET_PeerIdentity *initiator)
379 {
380  struct CadetClient *sc;
381 
382  GNUNET_assert (NULL != channel);
383  if (sc_count >= sc_count_max)
384  {
386  gettext_noop (
387  "# cadet client connections rejected"),
388  1,
389  GNUNET_NO);
391  return NULL;
392  }
394  gettext_noop ("# cadet connections active"),
395  1,
396  GNUNET_NO);
397  sc = GNUNET_new (struct CadetClient);
398  sc->channel = channel;
400  sc_tail,
401  sc);
402  sc_count++;
405  "Accepting inbound cadet connection from `%s' as client %p\n",
406  GNUNET_i2s (initiator),
407  sc);
408  return sc;
409 }
410 
411 
420 static void
421 disconnect_cb (void *cls,
422  const struct GNUNET_CADET_Channel *channel)
423 {
424  struct CadetClient *sc = cls;
425  struct WriteQueueItem *wqi;
426 
427  if (NULL == sc)
428  return;
429  sc->channel = NULL;
431  "Terminating cadet connection with client %p\n",
432  sc);
434  gettext_noop ("# cadet connections active"), -1,
435  GNUNET_NO);
436  if (NULL != sc->terminate_task)
438  if (NULL != sc->timeout_task)
440  if (NULL != sc->qe)
442  while (NULL != (wqi = sc->wqi_head))
443  {
445  sc->wqi_tail,
446  wqi);
447  GNUNET_free (wqi);
448  }
450  sc_tail,
451  sc);
452  sc_count--;
453  GNUNET_free (sc);
454 }
455 
456 
471 static void
472 window_change_cb (void *cls,
473  const struct GNUNET_CADET_Channel *channel,
474  int window_size)
475 {
476  /* FIXME: could do flow control here... */
477 }
478 
479 
483 void
485 {
486  struct GNUNET_MQ_MessageHandler handlers[] = {
489  struct CadetQueryMessage,
490  NULL),
492  };
493  struct GNUNET_HashCode port;
494 
495  if (GNUNET_YES !=
497  "fs",
498  "MAX_CADET_CLIENTS",
499  &sc_count_max))
500  return;
502  "Initializing cadet FS server with a limit of %llu connections\n",
503  sc_count_max);
506  GNUNET_assert (NULL != cadet_handle);
509  &port);
510  cadet_port = GNUNET_CADET_open_port (cadet_handle,
511  &port,
512  &connect_cb,
513  NULL,
515  &disconnect_cb,
516  handlers);
517 }
518 
519 
523 void
525 {
528  NULL);
530  cadet_map = NULL;
531  if (NULL != cadet_port)
532  {
533  GNUNET_CADET_close_port (cadet_port);
534  cadet_port = NULL;
535  }
536  if (NULL != cadet_handle)
537  {
539  cadet_handle = NULL;
540  }
541  GNUNET_assert (NULL == sc_head);
542  GNUNET_assert (0 == sc_count);
543 }
544 
545 
546 /* end of gnunet-service-fs_cadet.c */
static void * connect_cb(void *cls, struct GNUNET_CADET_Channel *channel, const struct GNUNET_PeerIdentity *initiator)
Functions of this type are called upon new cadet connection from other peers.
#define GNUNET_CONTAINER_DLL_remove(head, tail, element)
Remove an element from a DLL.
#define GNUNET_MESSAGE_TYPE_FS_CADET_REPLY
P2P answer for content (one FS to another via a cadet).
size_t msize
Number of bytes of payload, allocated at the end of this struct.
static struct GNUNET_CADET_Handle * cadet_handle
The handle to cadet.
void GNUNET_CADET_disconnect(struct GNUNET_CADET_Handle *handle)
Disconnect from the cadet service.
Definition: cadet_api.c:841
Query from one peer, asking the other for CHK-data.
static struct GNUNET_VPN_RedirectionRequest * request
Opaque redirection request handle.
Definition: gnunet-vpn.c:41
int 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.
static void handle_datastore_reply(void *cls, const struct GNUNET_HashCode *key, size_t size, const void *data, enum GNUNET_BLOCK_Type type, uint32_t priority, uint32_t anonymity, uint32_t replication, struct GNUNET_TIME_Absolute expiration, uint64_t uid)
Process a datum that was stored in the datastore.
#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.
struct GNUNET_SCHEDULER_Task * timeout_task
Task that is scheduled to terminate idle connections.
struct WriteQueueItem * next
Kept in a DLL.
struct GNUNET_SCHEDULER_Task * terminate_task
Task that is scheduled to asynchronously terminate the connection.
GNUNET_BLOCK_Type
Blocks in the datastore and the datacache must have a unique type.
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
static struct CadetClient * sc_head
Head of DLL of cadet clients.
static unsigned int replication
#define GNUNET_memcpy(dst, src, n)
Call memcpy() but check for n being 0 first.
#define GNUNET_MQ_hd_fixed_size(name, code, str, ctx)
static unsigned long long sc_count_max
Maximum allowed number of cadet clients.
uint32_t type
Block type must be DBLOCK or IBLOCK.
struct GNUNET_STATISTICS_Handle * GSF_stats
Handle for reporting statistics.
#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:80
#define GNUNET_OK
Named constants for return values.
Definition: gnunet_common.h:75
const char * GNUNET_h2s(const struct GNUNET_HashCode *hc)
Convert a hash value to a string (for printing debug messages).
#define GNUNET_new(type)
Allocate a struct or union of the given type.
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_CONTAINER_MultiPeerMap * GNUNET_CONTAINER_multipeermap_create(unsigned int len, int do_not_copy_keys)
Create a multi peer map (hash map for public keys of peers).
const struct GNUNET_CONFIGURATION_Handle * GSF_cfg
Our configuration.
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur...
Type of a block representing a block to be encoded on demand from disk.
void GNUNET_CONTAINER_multipeermap_destroy(struct GNUNET_CONTAINER_MultiPeerMap *map)
Destroy a hash map.
struct GNUNET_CADET_Handle * GNUNET_CADET_connect(const struct GNUNET_CONFIGURATION_Handle *cfg)
Connect to the MQ-based cadet service.
Definition: cadet_api.c:976
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 IDLE_TIMEOUT
After how long do we termiante idle connections?
#define GNUNET_MQ_msg_extra(mvar, esize, type)
Allocate an envelope, with extra space allocated after the space needed by the message struct...
Definition: gnunet_mq_lib.h:52
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:1253
static void refresh_timeout_task(struct CadetClient *sc)
Reset the timeout for the cadet client (due to activity).
Entry in our priority queue.
Definition: datastore_api.c:99
struct GNUNET_CADET_Port * GNUNET_CADET_open_port(struct GNUNET_CADET_Handle *h, const struct GNUNET_HashCode *port, GNUNET_CADET_ConnectEventHandler connects, void *connects_cls, GNUNET_CADET_WindowSizeEventHandler window_changes, GNUNET_CADET_DisconnectEventHandler disconnects, const struct GNUNET_MQ_MessageHandler *handlers)
Open a port to receive incomming MQ-based channels.
Definition: cadet_api.c:1010
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:774
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 unsigned int sc_count
Number of active cadet clients in the &#39;sc_*&#39;-DLL.
static void continue_writing(void *cls)
Check if we are done with the write queue, and if so tell CADET that we are ready to read more...
void GNUNET_CRYPTO_hash(const void *block, size_t size, struct GNUNET_HashCode *ret)
Compute hash of a given block.
Definition: crypto_hash.c:48
unsigned int GNUNET_MQ_get_length(struct GNUNET_MQ_Handle *mq)
Obtain the current length of the message queue.
Definition: mq.c:335
unsigned int GSF_datastore_queue_size
Size of the datastore queue we assume for common requests.
non-anonymous file-transfer
static void timeout_cadet_task(void *cls)
Task run to asynchronously terminate the cadet due to timeout.
struct GNUNET_CONTAINER_MultiPeerMap * cadet_map
Map from peer identities to &#39;struct CadetHandles&#39; with cadet channels to those peers.
struct WriteQueueItem * prev
Kept in a DLL.
struct WriteQueueItem * wqi_head
Head of write queue.
enum GNUNET_MQ_PriorityPreferences priority
Flags that were set for this queue by GNUNET_MQ_set_options().
Definition: mq.c:164
A 512-bit hashcode.
static char * expiration
Credential TTL.
Definition: gnunet-abd.c:96
Message handler for a specific message type.
struct GNUNET_DATASTORE_Handle * GSF_dsh
Our connection to the datastore.
void GSF_cadet_start_server()
Initialize subsystem for non-anonymous file-sharing.
Struct containing information about a client of the service.
struct GNUNET_HashCode key
The key used in the DHT.
static unsigned int size
Size of the "table".
Definition: peer.c:67
struct GNUNET_CADET_Channel * channel
Channel for communication.
void GSF_cadet_stop_server()
Shutdown subsystem for non-anonymous file-sharing.
struct GNUNET_MQ_Envelope * env
Definition: 005.c:1
struct GNUNET_TIME_AbsoluteNBO expiration
Expiration time for the block.
static struct GNUNET_FS_SearchContext * sc
Definition: gnunet-search.c:37
indexing for the file-sharing service
size_t reply_size
Size of the last write that was initiated.
#define GNUNET_MAX_MESSAGE_SIZE
Largest supported message (to be precise, one byte more than the largest possible message...
struct WriteQueueItem * wqi_tail
Tail of write queue.
Handle to a message queue.
Definition: mq.c:85
static void disconnect_cb(void *cls, const struct GNUNET_CADET_Channel *channel)
Function called by cadet when a client disconnects.
int GNUNET_CONTAINER_multipeermap_iterate(struct GNUNET_CONTAINER_MultiPeerMap *map, GNUNET_CONTAINER_PeerMapIterator it, void *it_cls)
Iterate over all entries in the map.
void GNUNET_DATASTORE_cancel(struct GNUNET_DATASTORE_QueueEntry *qe)
Cancel a datastore operation.
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:954
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:134
static void handle_request(void *cls, const struct CadetQueryMessage *sqm)
Functions with this signature are called whenever a complete query message is received.
Opaque handle to a port.
Definition: cadet_api.c:145
static struct GNUNET_CADET_Port * cadet_port
Listen port for incoming requests.
static struct CadetClient * sc_tail
Tail of DLL of cadet clients.
#define GNUNET_APPLICATION_PORT_FS_BLOCK_TRANSFER
Transfer of blocks for non-anonymmous file-sharing.
enum GNUNET_TESTBED_UnderlayLinkModelType type
the type of this model
void GNUNET_CADET_close_port(struct GNUNET_CADET_Port *p)
Close a port opened with GNUNET_CADET_open_port().
Definition: cadet_api.c:874
Time for absolute times used by GNUnet, in microseconds.
#define GNUNET_YES
Definition: gnunet_common.h:77
static unsigned int anonymity
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
uint32_t type
Block type must be DBLOCK or IBLOCK.
struct GNUNET_DATASTORE_QueueEntry * GNUNET_DATASTORE_get_key(struct GNUNET_DATASTORE_Handle *h, uint64_t next_uid, bool random, const struct GNUNET_HashCode *key, enum GNUNET_BLOCK_Type type, unsigned int queue_priority, unsigned int max_queue_size, GNUNET_DATASTORE_DatumProcessor proc, void *proc_cls)
Get a result for a particular key from the datastore.
int GNUNET_FS_handle_on_demand_block(const struct GNUNET_HashCode *key, uint32_t size, const void *data, enum GNUNET_BLOCK_Type type, uint32_t priority, uint32_t anonymity, uint32_t replication, struct GNUNET_TIME_Absolute expiration, uint64_t uid, GNUNET_DATASTORE_DatumProcessor cont, void *cont_cls)
We&#39;ve received an on-demand encoded block from the datastore.
uint32_t data
The data value.
struct GNUNET_TIME_AbsoluteNBO GNUNET_TIME_absolute_hton(struct GNUNET_TIME_Absolute a)
Convert absolute time to network byte order.
Definition: time.c:657
Reply to a CadetQueryMessage.
void GNUNET_CADET_channel_destroy(struct GNUNET_CADET_Channel *channel)
Destroy an existing channel.
Definition: cadet_api.c:903
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_DATASTORE_QueueEntry * qe
Current active request to the datastore, if we have one pending.
A message in the queue to be written to the cadet.
#define GNUNET_free(ptr)
Wrapper around free.
#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:1119
void * GNUNET_SCHEDULER_cancel(struct GNUNET_SCHEDULER_Task *task)
Cancel the task with the specified identifier.
Definition: scheduler.c:966