summaryrefslogtreecommitdiff
path: root/src/transport/gnunet-service-transport.c
blob: b148f289bcdd6bd29adf27bf250bfb17a482d0b8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
/*
     This file is part of GNUnet.
     (C) 2010,2011 Christian Grothoff (and other contributing authors)

     GNUnet is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published
     by the Free Software Foundation; either version 3, or (at your
     option) any later version.

     GNUnet is distributed in the hope that it will be useful, but
     WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     General Public License for more details.

     You should have received a copy of the GNU General Public License
     along with GNUnet; see the file COPYING.  If not, write to the
     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.
*/

/**
 * @file transport/gnunet-service-transport.c
 * @brief
 * @author Christian Grothoff
 */
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_hello_lib.h"
#include "gnunet_statistics_service.h"
#include "gnunet_transport_service.h"
#include "gnunet_peerinfo_service.h"
#include "gnunet_ats_service.h"
#include "gnunet-service-transport.h"
#include "gnunet-service-transport_blacklist.h"
#include "gnunet-service-transport_clients.h"
#include "gnunet-service-transport_hello.h"
#include "gnunet-service-transport_neighbours.h"
#include "gnunet-service-transport_plugins.h"
#include "gnunet-service-transport_validation.h"
#include "transport.h"

/* globals */

/**
 * Statistics handle.
 */
struct GNUNET_STATISTICS_Handle *GST_stats;

/**
 * Configuration handle.
 */
const struct GNUNET_CONFIGURATION_Handle *GST_cfg;

/**
 * Configuration handle.
 */
struct GNUNET_PeerIdentity GST_my_identity;

/**
 * Handle to peerinfo service.
 */
struct GNUNET_PEERINFO_Handle *GST_peerinfo;

/**
 * Our public key.
 */
struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded GST_my_public_key;

/**
 * Our private key.
 */
struct GNUNET_CRYPTO_RsaPrivateKey *GST_my_private_key;

/**
 * ATS handle.
 */
struct GNUNET_ATS_SchedulingHandle *GST_ats;


/**
 * Transmit our HELLO message to the given (connected) neighbour.
 *
 * @param cls the 'HELLO' message
 * @param target a connected neighbour
 * @param ats performance information (unused)
 * @param ats_count number of records in ats (unused)
 * @param address the address
 */
static void
transmit_our_hello (void *cls, const struct GNUNET_PeerIdentity *target,
                    const struct GNUNET_ATS_Information *ats,
                    uint32_t ats_count,
		    const struct GNUNET_HELLO_Address *address)
{
  const struct GNUNET_MessageHeader *hello = cls;

  GST_neighbours_send (target, (const char *) hello, ntohs (hello->size),
                       GNUNET_CONSTANTS_HELLO_ADDRESS_EXPIRATION, NULL, NULL);
}


/**
 * My HELLO has changed. Tell everyone who should know.
 *
 * @param cls unused
 * @param hello new HELLO
 */
static void
process_hello_update (void *cls, const struct GNUNET_MessageHeader *hello)
{
  GST_clients_broadcast (hello, GNUNET_NO);
  GST_neighbours_iterate (&transmit_our_hello, (void *) hello);
}



/**
 * We received some payload.  Prepare to pass it on to our clients.
 *
 * @param peer (claimed) identity of the other peer
 * @param message the message, never NULL
 * @param ats performance information
 * @param ats_count number of records in ats
 * @return how long the plugin should wait until receiving more data
 */
static struct GNUNET_TIME_Relative
process_payload (const struct GNUNET_PeerIdentity *peer,
                 const struct GNUNET_HELLO_Address *address,
                 struct Session *session,
                 const struct GNUNET_MessageHeader *message,
                 const struct GNUNET_ATS_Information *ats, uint32_t ats_count)
{
  struct GNUNET_TIME_Relative ret;
  int do_forward;
  struct InboundMessage *im;
  size_t msg_size = ntohs (message->size);
  size_t size =
      sizeof (struct InboundMessage) + msg_size +
    sizeof (struct GNUNET_ATS_Information) * (ats_count + 1);
  char buf[size];
  struct GNUNET_ATS_Information *ap;

  ret = GNUNET_TIME_UNIT_ZERO;
  do_forward = GNUNET_SYSERR;
  ret = GST_neighbours_calculate_receive_delay (peer, msg_size, &do_forward);

  if (!GST_neighbours_test_connected (peer))
  {

    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
                "Discarded %u bytes type %u payload from peer `%s'\n", msg_size,
                ntohs (message->type), GNUNET_i2s (peer));

    GNUNET_STATISTICS_update (GST_stats,
                              gettext_noop
                              ("# bytes payload discarded due to not connected peer "),
                              msg_size, GNUNET_NO);
    return ret;
  }

  if (do_forward != GNUNET_YES)
    return ret;
  im = (struct InboundMessage *) buf;
  im->header.size = htons (size);
  im->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_RECV);
  im->ats_count = htonl (ats_count + 1);
  im->peer = *peer;
  ap = (struct GNUNET_ATS_Information *) &im[1];
  memcpy (ap, ats, ats_count * sizeof (struct GNUNET_ATS_Information));
  ap[ats_count].type = htonl (GNUNET_ATS_QUALITY_NET_DELAY);
  ap[ats_count].value = htonl ((uint32_t) GST_neighbour_get_latency (peer).rel_value);
  memcpy (&ap[ats_count + 1], message, ntohs (message->size));

  GNUNET_ATS_address_update (GST_ats, address, session, ap, ats_count +1 );
  GST_clients_broadcast (&im->header, GNUNET_YES);

  return ret;
}


/**
 * Function called by the transport for each received message.
 * This function should also be called with "NULL" for the
 * message to signal that the other peer disconnected.
 *
 * @param cls closure, const char* with the name of the plugin we received the message from
 * @param peer (claimed) identity of the other peer
 * @param message the message, NULL if we only care about
 *                learning about the delay until we should receive again -- FIXME!
 * @param ats performance information
 * @param ats_count number of records in ats
 * @param session identifier used for this session (NULL for plugins
 *                that do not offer bi-directional communication to the sender
 *                using the same "connection")
 * @param sender_address binary address of the sender (if we established the
 *                connection or are otherwise sure of it; should be NULL
 *                for inbound TCP/UDP connections since it it not clear
 *                that we could establish ourselves a connection to that
 *                IP address and get the same system)
 * @param sender_address_len number of bytes in sender_address
 * @return how long the plugin should wait until receiving more data
 *         (plugins that do not support this, can ignore the return value)
 */
static struct GNUNET_TIME_Relative
plugin_env_receive_callback (void *cls, 
			     const struct GNUNET_PeerIdentity *peer,
                             const struct GNUNET_MessageHeader *message,
                             const struct GNUNET_ATS_Information *ats,
                             uint32_t ats_count, struct Session *session,
                             const char *sender_address,
                             uint16_t sender_address_len)
{
  const char *plugin_name = cls;
  struct GNUNET_TIME_Relative ret;
  struct GNUNET_HELLO_Address address;
  uint16_t type;

  address.peer = *peer;
  address.address = sender_address;
  address.address_length = sender_address_len;
  address.transport_name = plugin_name;
  ret = GNUNET_TIME_UNIT_ZERO;
  if (NULL == message)
    goto end;
  type = ntohs (message->type);
#if DEBUG_TRANSPORT

  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Received Message with type %u\n", type);
#endif

  switch (type)
  {
  case GNUNET_MESSAGE_TYPE_HELLO:
    GST_validation_handle_hello (message);
    return ret;
  case GNUNET_MESSAGE_TYPE_TRANSPORT_PING:
#if DEBUG_TRANSPORT
    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
                "Processing `%s' from `%s'\n", "PING",
                (sender_address != NULL) ? GST_plugins_a2s (&address)
                : "<inbound>");
#endif
    GST_validation_handle_ping (peer, message, &address, session);
    break;
  case GNUNET_MESSAGE_TYPE_TRANSPORT_PONG:
#if DEBUG_TRANSPORT
    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG | GNUNET_ERROR_TYPE_BULK,
                "Processing `%s' from `%s'\n", "PONG",
                (sender_address != NULL) ? GST_plugins_a2s (&address)
                : "<inbound>");
#endif
    GST_validation_handle_pong (peer, message);
    break;
  case GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_CONNECT:
    GST_neighbours_handle_connect (message, peer, &address, session, ats, ats_count);
    break;
  case GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_CONNECT_ACK:
    GST_neighbours_handle_connect_ack (message, peer, &address,
                                       session, ats, ats_count);
    break;
  case GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_ACK:
    GST_neighbours_handle_ack (message, peer, &address, session, ats, ats_count);
    break;
  case GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_DISCONNECT:
    GST_neighbours_handle_disconnect_message (peer, message);
    break;
  case GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE:
    GST_neighbours_keepalive (peer);
    break;
  case GNUNET_MESSAGE_TYPE_TRANSPORT_SESSION_KEEPALIVE_RESPONSE:
    GST_neighbours_keepalive_response (peer, ats, ats_count);
    break;
  default:
    /* should be payload */
    ret = process_payload (peer, &address, session, message, ats, ats_count);
    break;
  }
end:
#if 1
  /* FIXME: this should not be needed, and not sure it's good to have it, but without
   * this connections seem to go extra-slow */
  GNUNET_ATS_address_update (GST_ats, &address, session, ats, ats_count);
#endif
#if DEBUG_TRANSPORT
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Allowing receive from peer %s to continue in %llu ms\n",
              GNUNET_i2s (peer), (unsigned long long) ret.rel_value);
#endif
  return ret;
}


/**
 * Function that will be called for each address the transport
 * is aware that it might be reachable under.  Update our HELLO.
 *
 * @param cls name of the plugin (const char*)
 * @param add_remove should the address added (YES) or removed (NO) from the
 *                   set of valid addresses?
 * @param addr one of the addresses of the host
 *        the specific address format depends on the transport
 * @param addrlen length of the address
 */
static void
plugin_env_address_change_notification (void *cls, int add_remove,
                                        const void *addr, size_t addrlen)
{
  const char *plugin_name = cls;
  struct GNUNET_HELLO_Address address;

  address.peer = GST_my_identity;
  address.transport_name = plugin_name;
  address.address = addr;
  address.address_length = addrlen;
  GST_hello_modify_addresses (add_remove, &address);
}


/**
 * Function that will be called whenever the plugin internally
 * cleans up a session pointer and hence the service needs to
 * discard all of those sessions as well.  Plugins that do not
 * use sessions can simply omit calling this function and always
 * use NULL wherever a session pointer is needed.  This function
 * should be called BEFORE a potential "TransmitContinuation"
 * from the "TransmitFunction".
 *
 * @param cls closure
 * @param peer which peer was the session for
 * @param session which session is being destoyed
 */
static void
plugin_env_session_end (void *cls, const struct GNUNET_PeerIdentity *peer,
                        struct Session *session)
{
  const char *transport_name = cls;
  struct GNUNET_HELLO_Address address;

  GNUNET_assert (strlen(transport_name) > 0);
#if DEBUG_TRANSPORT
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Session %X to peer `%s' ended \n",
              session, GNUNET_i2s (peer));
#endif
  if (NULL != session)
    GNUNET_log_from (GNUNET_ERROR_TYPE_INFO | GNUNET_ERROR_TYPE_BULK,
                     "transport-ats",
                     "Telling ATS to destroy session %p from peer %s\n",
                     session, GNUNET_i2s (peer));
  address.peer = *peer;
  address.address = NULL;
  address.address_length = 0;
  address.transport_name = transport_name;
  GST_neighbours_session_terminated (peer, session);
  GNUNET_ATS_address_destroyed (GST_ats, &address, session);
}


/**
 * Function called by ATS to notify the callee that the
 * assigned bandwidth or address for a given peer was changed.  If the
 * callback is called with address/bandwidth assignments of zero, the
 * ATS disconnect function will still be called once the disconnect
 * actually happened.
 *
 * @param cls closure
 * @param address address to use (for peer given in address)
 * @param session session to use (if available)
 * @param bandwidth_out assigned outbound bandwidth for the connection, 0 to disconnect from peer
 * @param bandwidth_in assigned inbound bandwidth for the connection, 0 to disconnect from peer
 */
static void
ats_request_address_change (void *cls, 
			    const struct GNUNET_HELLO_Address *address,
                            struct Session *session,
                            struct GNUNET_BANDWIDTH_Value32NBO bandwidth_out,
                            struct GNUNET_BANDWIDTH_Value32NBO bandwidth_in,
                            const struct GNUNET_ATS_Information *ats,
                            uint32_t ats_count)
{
  uint32_t bw_in = ntohl (bandwidth_in.value__);
  uint32_t bw_out = ntohl (bandwidth_out.value__);

  /* ATS tells me to disconnect from peer */
  if ((bw_in == 0) && (bw_out == 0))
  {
#if DEBUG_TRANSPORT
    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
                "ATS tells me to disconnect from peer `%s'\n",
                GNUNET_i2s (&address->peer));
#endif
    GST_neighbours_force_disconnect (&address->peer);
    return;
  }
  /* will never return GNUNET_YES since connection is to be established */
  GST_neighbours_switch_to_address_3way (&address->peer, 
					 address, session, ats,
                                         ats_count, bandwidth_in,
                                         bandwidth_out);
}


/**
 * Function called to notify transport users that another
 * peer connected to us.
 *
 * @param cls closure
 * @param peer the peer that connected
 * @param ats performance data
 * @param ats_count number of entries in ats
 */
static void
neighbours_connect_notification (void *cls,
                                 const struct GNUNET_PeerIdentity *peer,
                                 const struct GNUNET_ATS_Information *ats,
                                 uint32_t ats_count)
{
  size_t len =
      sizeof (struct ConnectInfoMessage) +
      ats_count * sizeof (struct GNUNET_ATS_Information);
  char buf[len];
  struct ConnectInfoMessage *connect_msg = (struct ConnectInfoMessage *) buf;
  struct GNUNET_ATS_Information *ap;

  connect_msg->header.size = htons (sizeof (buf));
  connect_msg->header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_CONNECT);
  connect_msg->ats_count = htonl (ats_count);
  connect_msg->id = *peer;
  ap = (struct GNUNET_ATS_Information *) &connect_msg[1];
  memcpy (ap, ats, ats_count * sizeof (struct GNUNET_ATS_Information));
  GST_clients_broadcast (&connect_msg->header, GNUNET_NO);
}


/**
 * Function called to notify transport users that another
 * peer disconnected from us.
 *
 * @param cls closure
 * @param peer the peer that disconnected
 */
static void
neighbours_disconnect_notification (void *cls,
                                    const struct GNUNET_PeerIdentity *peer)
{
  struct DisconnectInfoMessage disconnect_msg;

  disconnect_msg.header.size = htons (sizeof (struct DisconnectInfoMessage));
  disconnect_msg.header.type = htons (GNUNET_MESSAGE_TYPE_TRANSPORT_DISCONNECT);
  disconnect_msg.reserved = htonl (0);
  disconnect_msg.peer = *peer;
  GST_clients_broadcast (&disconnect_msg.header, GNUNET_NO);
}


/**
 * Function called when the service shuts down.  Unloads our plugins
 * and cancels pending validations.
 *
 * @param cls closure, unused
 * @param tc task context (unused)
 */
static void
shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
{
  GST_neighbours_stop ();
  GST_validation_stop ();
  GST_plugins_unload ();

  GNUNET_ATS_scheduling_done (GST_ats);
  GST_ats = NULL;
  GST_clients_stop ();
  GST_blacklist_stop ();
  GST_hello_stop ();

  if (GST_peerinfo != NULL)
  {
    GNUNET_PEERINFO_disconnect (GST_peerinfo);
    GST_peerinfo = NULL;
  }
  if (GST_stats != NULL)
  {
    GNUNET_STATISTICS_destroy (GST_stats, GNUNET_NO);
    GST_stats = NULL;
  }
  if (GST_my_private_key != NULL)
  {
    GNUNET_CRYPTO_rsa_key_free (GST_my_private_key);
    GST_my_private_key = NULL;
  }
}


/**
 * Initiate transport service.
 *
 * @param cls closure
 * @param server the initialized server
 * @param c configuration to use
 */
static void
run (void *cls, struct GNUNET_SERVER_Handle *server,
     const struct GNUNET_CONFIGURATION_Handle *c)
{
  char *keyfile;

  /* setup globals */
  GST_cfg = c;
  if (GNUNET_OK !=
      GNUNET_CONFIGURATION_get_value_filename (c, "GNUNETD", "HOSTKEY",
                                               &keyfile))
  {
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                _
                ("Transport service is lacking key configuration settings.  Exiting.\n"));
    GNUNET_SCHEDULER_shutdown ();
    return;
  }
  GST_my_private_key = GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
  GNUNET_free (keyfile);
  if (GST_my_private_key == NULL)
  {
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                _("Transport service could not access hostkey.  Exiting.\n"));
    GNUNET_SCHEDULER_shutdown ();
    return;
  }
  GST_stats = GNUNET_STATISTICS_create ("transport", c);
  GST_peerinfo = GNUNET_PEERINFO_connect (c);
  GNUNET_CRYPTO_rsa_key_get_public (GST_my_private_key, &GST_my_public_key);
  GNUNET_CRYPTO_hash (&GST_my_public_key, sizeof (GST_my_public_key),
                      &GST_my_identity.hashPubKey);
  GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &shutdown_task,
                                NULL);
  if (GST_peerinfo == NULL)
  {
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                _("Could not access PEERINFO service.  Exiting.\n"));
    GNUNET_SCHEDULER_shutdown ();
    return;
  }

  /* start subsystems */
  GST_hello_start (&process_hello_update, NULL);
  GST_blacklist_start (server);
  GST_plugins_load (&plugin_env_receive_callback,
                    &plugin_env_address_change_notification,
                    &plugin_env_session_end);
  GST_ats =
      GNUNET_ATS_scheduling_init (GST_cfg, &ats_request_address_change, NULL);
  GST_neighbours_start (NULL, &neighbours_connect_notification,
                        &neighbours_disconnect_notification);
  GST_clients_start (server);
  GST_validation_start ();
}


/**
 * The main function for the transport service.
 *
 * @param argc number of arguments from the command line
 * @param argv command line arguments
 * @return 0 ok, 1 on error
 */
int
main (int argc, char *const *argv)
{
  return (GNUNET_OK ==
          GNUNET_SERVICE_run (argc, argv, "transport",
                              GNUNET_SERVICE_OPTION_NONE, &run, NULL)) ? 0 : 1;
}

/* end of file gnunet-service-transport-new.c */