aboutsummaryrefslogtreecommitdiff
path: root/src/nat/nat_test.c
blob: eda9695024afbf483298601ec4d2853455fb093d (plain) (blame)
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
/*
     This file is part of GNUnet.
     Copyright (C) 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., 51 Franklin Street, Fifth Floor,
     Boston, MA 02110-1301, USA.
*/

/**
 * @file nat/nat_test.c
 * @brief functions to test if the NAT configuration is successful at achieving NAT traversal (with the help of a gnunet-nat-server)
 * @author Christian Grothoff
 */
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_nat_lib.h"
#include "nat.h"

#define LOG(kind,...) GNUNET_log_from (kind, "nat", __VA_ARGS__)

#define NAT_SERVER_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 30)

/**
 * Entry we keep for each incoming connection.
 */
struct NatActivity
{
  /**
   * This is a doubly-linked list.
   */
  struct NatActivity *next;

  /**
   * This is a doubly-linked list.
   */
  struct NatActivity *prev;

  /**
   * Socket of the incoming connection.
   */
  struct GNUNET_NETWORK_Handle *sock;

  /**
   * Handle of the master context.
   */
  struct GNUNET_NAT_Test *h;

  /**
   * Task reading from the incoming connection.
   */
  struct GNUNET_SCHEDULER_Task * rtask;
};


/**
 * Entry we keep for each connection to the gnunet-nat-service.
 */
struct ClientActivity
{
  /**
   * This is a doubly-linked list.
   */
  struct ClientActivity *next;

  /**
   * This is a doubly-linked list.
   */
  struct ClientActivity *prev;

  /**
   * Socket of the incoming connection.
   */
  struct GNUNET_CLIENT_Connection *client;

};


/**
 * Handle to a NAT test.
 */
struct GNUNET_NAT_Test
{

  /**
   * Configuration used
   */
  const struct GNUNET_CONFIGURATION_Handle *cfg;

  /**
   * Function to call with success report
   */
  GNUNET_NAT_TestCallback report;

  /**
   * Closure for @e report.
   */
  void *report_cls;

  /**
   * Handle to NAT traversal in use
   */
  struct GNUNET_NAT_Handle *nat;

  /**
   * Handle to listen socket, or NULL
   */
  struct GNUNET_NETWORK_Handle *lsock;

  /**
   * Head of list of nat activities.
   */
  struct NatActivity *na_head;

  /**
   * Tail of list of nat activities.
   */
  struct NatActivity *na_tail;

  /**
   * Head of list of client activities.
   */
  struct ClientActivity *ca_head;

  /**
   * Tail of list of client activities.
   */
  struct ClientActivity *ca_tail;

  /**
   * Identity of task for the listen socket (if any)
   */
  struct GNUNET_SCHEDULER_Task * ltask;

  /**
   * Task identifier for the timeout (if any)
   */
  struct GNUNET_SCHEDULER_Task * ttask;

  /**
   * GNUNET_YES if we're testing TCP
   */
  int is_tcp;

  /**
   * Data that should be transmitted or source-port.
   */
  uint16_t data;

  /**
   * Advertised port to the other peer.
   */
  uint16_t adv_port;

  /**
   * Status code to be reported to the timeout/status call
   */
  enum GNUNET_NAT_StatusCode status;
};


/**
 * Function called from #GNUNET_NAT_register whenever someone asks us
 * to do connection reversal.
 *
 * @param cls closure, our `struct GNUNET_NAT_Handle`
 * @param addr public IP address of the other peer
 * @param addrlen actual lenght of the address
 */
static void
reversal_cb (void *cls,
             const struct sockaddr *addr,
             socklen_t addrlen)
{
  struct GNUNET_NAT_Test *h = cls;
  const struct sockaddr_in *sa;

  if (sizeof (struct sockaddr_in) != addrlen)
    return;
  sa = (const struct sockaddr_in *) addr;
  if (h->data != sa->sin_port)
  {
    LOG (GNUNET_ERROR_TYPE_DEBUG,
         "Received connection reversal request for wrong port\n");
    return;                     /* wrong port */
  }
  /* report success */
  h->report (h->report_cls, GNUNET_NAT_ERROR_SUCCESS);
}


/**
 * Activity on our incoming socket.  Read data from the
 * incoming connection.
 *
 * @param cls the `struct GNUNET_NAT_Test`
 * @param tc scheduler context
 */
static void
do_udp_read (void *cls,
             const struct GNUNET_SCHEDULER_TaskContext *tc)
{
  struct GNUNET_NAT_Test *tst = cls;
  uint16_t data;

  tst->ltask =
      GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
                                     tst->lsock,
                                     &do_udp_read, tst);
  if ((NULL != tc->write_ready) &&
      (GNUNET_NETWORK_fdset_isset (tc->read_ready, tst->lsock)) &&
      (sizeof (data) ==
       GNUNET_NETWORK_socket_recv (tst->lsock, &data, sizeof (data))))
  {
    if (data == tst->data)
      tst->report (tst->report_cls, GNUNET_NAT_ERROR_SUCCESS);
    else
      LOG (GNUNET_ERROR_TYPE_DEBUG,
           "Received data mismatches expected value\n");
  }
  else
    LOG (GNUNET_ERROR_TYPE_DEBUG,
         "Failed to receive data from inbound connection\n");
}


/**
 * Activity on our incoming socket.  Read data from the
 * incoming connection.
 *
 * @param cls the `struct NatActivity`
 * @param tc scheduler context
 */
static void
do_read (void *cls,
         const struct GNUNET_SCHEDULER_TaskContext *tc)
{
  struct NatActivity *na = cls;
  struct GNUNET_NAT_Test *tst;
  uint16_t data;

  na->rtask = NULL;
  tst = na->h;
  GNUNET_CONTAINER_DLL_remove (tst->na_head, tst->na_tail, na);
  if ((NULL != tc->write_ready) &&
      (GNUNET_NETWORK_fdset_isset (tc->read_ready, na->sock)) &&
      (sizeof (data) ==
       GNUNET_NETWORK_socket_recv (na->sock, &data, sizeof (data))))
  {
    if (data == tst->data)
      tst->report (tst->report_cls, GNUNET_NAT_ERROR_SUCCESS);
    else
      LOG (GNUNET_ERROR_TYPE_DEBUG,
           "Received data does not match expected value\n");
  }
  else
    LOG (GNUNET_ERROR_TYPE_DEBUG,
         "Failed to receive data from inbound connection\n");
  GNUNET_NETWORK_socket_close (na->sock);
  GNUNET_free (na);
}


/**
 * Activity on our listen socket. Accept the
 * incoming connection.
 *
 * @param cls the `struct GNUNET_NAT_Test`
 * @param tc scheduler context
 */
static void
do_accept (void *cls,
           const struct GNUNET_SCHEDULER_TaskContext *tc)
{
  struct GNUNET_NAT_Test *tst = cls;
  struct GNUNET_NETWORK_Handle *s;
  struct NatActivity *wl;

  tst->ltask = NULL;
  if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
    return;
  tst->ltask =
      GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL, tst->lsock,
                                     &do_accept, tst);
  s = GNUNET_NETWORK_socket_accept (tst->lsock, NULL, NULL);
  if (NULL == s)
  {
    GNUNET_log_strerror (GNUNET_ERROR_TYPE_INFO, "accept");
    return;                     /* odd error */
  }
  LOG (GNUNET_ERROR_TYPE_DEBUG,
       "Got an inbound connection, waiting for data\n");
  wl = GNUNET_new (struct NatActivity);
  wl->sock = s;
  wl->h = tst;
  wl->rtask =
    GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
                                   wl->sock,
                                   &do_read, wl);
  GNUNET_CONTAINER_DLL_insert (tst->na_head, tst->na_tail, wl);
}


/**
 * Address-callback, used to send message to gnunet-nat-server.
 *
 * @param cls closure
 * @param add_remove #GNUNET_YES to mean the new public IP address, #GNUNET_NO to mean
 *     the previous (now invalid) one
 * @param addr either the previous or the new public IP address
 * @param addrlen actual length of the @a addr
 */
static void
addr_cb (void *cls,
         int add_remove,
         const struct sockaddr *addr,
         socklen_t addrlen)
{
  struct GNUNET_NAT_Test *h = cls;
  struct ClientActivity *ca;
  struct GNUNET_CLIENT_Connection *client;
  struct GNUNET_NAT_TestMessage msg;
  const struct sockaddr_in *sa;

  if (GNUNET_YES != add_remove)
    return;
  if (addrlen != sizeof (struct sockaddr_in))
  {
    LOG (GNUNET_ERROR_TYPE_DEBUG,
	 "NAT test ignores IPv6 address `%s' returned from NAT library\n",
	 GNUNET_a2s (addr, addrlen));
    return;                     /* ignore IPv6 here */
  }
  LOG (GNUNET_ERROR_TYPE_INFO,
       "Asking gnunet-nat-server to connect to `%s'\n",
       GNUNET_a2s (addr, addrlen));
  sa = (const struct sockaddr_in *) addr;
  msg.header.size = htons (sizeof (struct GNUNET_NAT_TestMessage));
  msg.header.type = htons (GNUNET_MESSAGE_TYPE_NAT_TEST);
  msg.dst_ipv4 = sa->sin_addr.s_addr;
  msg.dport = sa->sin_port;
  msg.data = h->data;
  msg.is_tcp = htonl ((uint32_t) h->is_tcp);

  client = GNUNET_CLIENT_connect ("gnunet-nat-server", h->cfg);
  if (NULL == client)
  {
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                _("Failed to connect to `gnunet-nat-server'\n"));
    return;
  }
  ca = GNUNET_new (struct ClientActivity);
  ca->client = client;
  GNUNET_CONTAINER_DLL_insert (h->ca_head, h->ca_tail, ca);
  GNUNET_break (GNUNET_OK ==
                GNUNET_CLIENT_transmit_and_get_response (client, &msg.header,
                                                         NAT_SERVER_TIMEOUT,
                                                         GNUNET_YES, NULL,
                                                         NULL));
}


/**
 * Timeout task for a nat test.
 * Calls the report-callback with a timeout return value
 *
 * Destroys the nat handle after the callback has been processed.
 *
 * @param cls handle to the timed out NAT test
 * @param tc not used
 */
static void
do_timeout (void *cls,
            const struct GNUNET_SCHEDULER_TaskContext *tc)
{
  struct GNUNET_NAT_Test *nh = cls;

  nh->ttask = NULL;
  nh->report (nh->report_cls,
              (GNUNET_NAT_ERROR_SUCCESS == nh->status)
              ? GNUNET_NAT_ERROR_TIMEOUT
              : nh->status);
}


/**
 * Start testing if NAT traversal works using the
 * given configuration (IPv4-only).
 *
 * ALL failures are reported directly to the report callback
 *
 * @param cfg configuration for the NAT traversal
 * @param is_tcp #GNUNET_YES to test TCP, #GNUNET_NO to test UDP
 * @param bnd_port port to bind to, 0 for connection reversal
 * @param adv_port externally advertised port to use
 * @param timeout delay after which the test should be aborted
 * @param report function to call with the result of the test
 * @param report_cls closure for @a report
 * @return handle to cancel NAT test or NULL. The error is always indicated via the report callback
 */
struct GNUNET_NAT_Test *
GNUNET_NAT_test_start (const struct GNUNET_CONFIGURATION_Handle *cfg,
                       int is_tcp,
                       uint16_t bnd_port,
                       uint16_t adv_port,
                       struct GNUNET_TIME_Relative timeout,
                       GNUNET_NAT_TestCallback report,
                       void *report_cls)
{
  struct GNUNET_NAT_Test *nh;
  struct sockaddr_in sa;
  const struct sockaddr *addrs[] = { (const struct sockaddr *) &sa };
  const socklen_t addrlens[] = { sizeof (sa) };

  memset (&sa, 0, sizeof (sa));
  sa.sin_family = AF_INET;
  sa.sin_port = htons (bnd_port);
#if HAVE_SOCKADDR_IN_SIN_LEN
  sa.sin_len = sizeof (sa);
#endif

  nh = GNUNET_new (struct GNUNET_NAT_Test);
  nh->cfg = cfg;
  nh->is_tcp = is_tcp;
  nh->data = bnd_port;
  nh->adv_port = adv_port;
  nh->report = report;
  nh->report_cls = report_cls;
  nh->status = GNUNET_NAT_ERROR_SUCCESS;
  if (0 == bnd_port)
  {
    nh->nat 
      = GNUNET_NAT_register (cfg, is_tcp, 0, 0, 
			     NULL, NULL,
			     &addr_cb,
                             &reversal_cb, nh);
  }
  else
  {
    nh->lsock =
        GNUNET_NETWORK_socket_create (AF_INET,
                                      (is_tcp ==
                                       GNUNET_YES) ? SOCK_STREAM : SOCK_DGRAM,
                                      0);
    if ((nh->lsock == NULL) ||
        (GNUNET_OK !=
         GNUNET_NETWORK_socket_bind (nh->lsock, (const struct sockaddr *) &sa,
                                     sizeof (sa))))
    {
      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                  _("Failed to create listen socket bound to `%s' for NAT test: %s\n"),
                  GNUNET_a2s ((const struct sockaddr *) &sa, sizeof (sa)),
                  STRERROR (errno));
      if (NULL != nh->lsock)
      {
        GNUNET_NETWORK_socket_close (nh->lsock);
        nh->lsock = NULL;
      }
      nh->status = GNUNET_NAT_ERROR_INTERNAL_NETWORK_ERROR;
      nh->ttask = GNUNET_SCHEDULER_add_now (&do_timeout, nh);
      return nh;
    }
    if (GNUNET_YES == is_tcp)
    {
      GNUNET_break (GNUNET_OK == GNUNET_NETWORK_socket_listen (nh->lsock, 5));
      nh->ltask =
          GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
                                         nh->lsock, &do_accept, nh);
    }
    else
    {
      nh->ltask =
          GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
                                         nh->lsock, &do_udp_read, nh);
    }
    LOG (GNUNET_ERROR_TYPE_DEBUG,
	 "NAT test listens on port %u (%s)\n",
	 bnd_port,
	 (GNUNET_YES == is_tcp) ? "tcp" : "udp");
    nh->nat = GNUNET_NAT_register (cfg, is_tcp, adv_port, 1,
                                   addrs, addrlens,
                                   &addr_cb, NULL, nh);
    if (NULL == nh->nat)
    {
      LOG (GNUNET_ERROR_TYPE_ERROR,
          _("NAT test failed to start NAT library\n"));
      if (NULL != nh->ltask)
      {
        GNUNET_SCHEDULER_cancel (nh->ltask);
        nh->ltask = NULL;
      }
      if (NULL != nh->lsock)
      {
        GNUNET_NETWORK_socket_close (nh->lsock);
        nh->lsock = NULL;
      }
      nh->status = GNUNET_NAT_ERROR_NAT_REGISTER_FAILED;
      nh->ttask = GNUNET_SCHEDULER_add_now (&do_timeout, nh);
      return nh;
    }
  }
  nh->ttask = GNUNET_SCHEDULER_add_delayed (timeout, &do_timeout, nh);
  return nh;
}


/**
 * Stop an active NAT test.
 *
 * @param tst test to stop.
 */
void
GNUNET_NAT_test_stop (struct GNUNET_NAT_Test *tst)
{
  struct NatActivity *pos;
  struct ClientActivity *cpos;

  LOG (GNUNET_ERROR_TYPE_DEBUG,
       "Stopping NAT test\n");
  while (NULL != (cpos = tst->ca_head))
  {
    GNUNET_CONTAINER_DLL_remove (tst->ca_head, tst->ca_tail, cpos);
    GNUNET_CLIENT_disconnect (cpos->client);
    GNUNET_free (cpos);
  }
  while (NULL != (pos = tst->na_head))
  {
    GNUNET_CONTAINER_DLL_remove (tst->na_head, tst->na_tail, pos);
    GNUNET_SCHEDULER_cancel (pos->rtask);
    GNUNET_NETWORK_socket_close (pos->sock);
    GNUNET_free (pos);
  }
  if (NULL != tst->ttask)
    GNUNET_SCHEDULER_cancel (tst->ttask);
  if (NULL != tst->ltask)
    GNUNET_SCHEDULER_cancel (tst->ltask);
  if (NULL != tst->lsock)
    GNUNET_NETWORK_socket_close (tst->lsock);
  if (NULL != tst->nat)
    GNUNET_NAT_unregister (tst->nat);
  GNUNET_free (tst);
}

/* end of nat_test.c */