aboutsummaryrefslogtreecommitdiff
path: root/lib/vtls/vtls.c
blob: fe69306de0b61ae2eef9a00214f78a4099cdbbbd (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
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
 * are also available at https://curl.haxx.se/docs/copyright.html.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ***************************************************************************/

/* This file is for implementing all "generic" SSL functions that all libcurl
   internals should use. It is then responsible for calling the proper
   "backend" function.

   SSL-functions in libcurl should call functions in this source file, and not
   to any specific SSL-layer.

   Curl_ssl_ - prefix for generic ones
   Curl_ossl_ - prefix for OpenSSL ones
   Curl_gtls_ - prefix for GnuTLS ones
   Curl_nss_ - prefix for NSS ones
   Curl_gskit_ - prefix for GSKit ones
   Curl_polarssl_ - prefix for PolarSSL ones
   Curl_cyassl_ - prefix for CyaSSL ones
   Curl_schannel_ - prefix for Schannel SSPI ones
   Curl_darwinssl_ - prefix for SecureTransport (Darwin) ones

   Note that this source code uses curlssl_* functions, and they are all
   defines/macros #defined by the lib-specific header files.

   "SSL/TLS Strong Encryption: An Introduction"
   https://httpd.apache.org/docs/2.0/ssl/ssl_intro.html
*/

#include "curl_setup.h"

#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif

#include "urldata.h"

#include "vtls.h" /* generic SSL protos etc */
#include "slist.h"
#include "sendf.h"
#include "rawstr.h"
#include "url.h"
#include "progress.h"
#include "share.h"
#include "timeval.h"
#include "curl_md5.h"
#include "warnless.h"
#include "curl_base64.h"
#include "curl_printf.h"

/* The last #include files should be: */
#include "curl_memory.h"
#include "memdebug.h"

/* convenience macro to check if this handle is using a shared SSL session */
#define SSLSESSION_SHARED(data) (data->share &&                        \
                                 (data->share->specifier &             \
                                  (1<<CURL_LOCK_DATA_SSL_SESSION)))

static bool safe_strequal(char* str1, char* str2)
{
  if(str1 && str2)
    /* both pointers point to something then compare them */
    return (0 != Curl_raw_equal(str1, str2)) ? TRUE : FALSE;
  else
    /* if both pointers are NULL then treat them as equal */
    return (!str1 && !str2) ? TRUE : FALSE;
}

bool
Curl_ssl_config_matches(struct ssl_config_data* data,
                        struct ssl_config_data* needle)
{
  if((data->version == needle->version) &&
     (data->verifypeer == needle->verifypeer) &&
     (data->verifyhost == needle->verifyhost) &&
     safe_strequal(data->CApath, needle->CApath) &&
     safe_strequal(data->CAfile, needle->CAfile) &&
     safe_strequal(data->clientcert, needle->clientcert) &&
     safe_strequal(data->cipher_list, needle->cipher_list))
    return TRUE;

  return FALSE;
}

bool
Curl_clone_ssl_config(struct ssl_config_data *source,
                      struct ssl_config_data *dest)
{
  dest->sessionid = source->sessionid;
  dest->verifyhost = source->verifyhost;
  dest->verifypeer = source->verifypeer;
  dest->version = source->version;

  if(source->CAfile) {
    dest->CAfile = strdup(source->CAfile);
    if(!dest->CAfile)
      return FALSE;
  }
  else
    dest->CAfile = NULL;

  if(source->CApath) {
    dest->CApath = strdup(source->CApath);
    if(!dest->CApath)
      return FALSE;
  }
  else
    dest->CApath = NULL;

  if(source->cipher_list) {
    dest->cipher_list = strdup(source->cipher_list);
    if(!dest->cipher_list)
      return FALSE;
  }
  else
    dest->cipher_list = NULL;

  if(source->egdsocket) {
    dest->egdsocket = strdup(source->egdsocket);
    if(!dest->egdsocket)
      return FALSE;
  }
  else
    dest->egdsocket = NULL;

  if(source->random_file) {
    dest->random_file = strdup(source->random_file);
    if(!dest->random_file)
      return FALSE;
  }
  else
    dest->random_file = NULL;

  if(source->clientcert) {
    dest->clientcert = strdup(source->clientcert);
    if(!dest->clientcert)
      return FALSE;
    dest->sessionid = FALSE;
  }
  else
    dest->clientcert = NULL;

  return TRUE;
}

void Curl_free_ssl_config(struct ssl_config_data* sslc)
{
  Curl_safefree(sslc->CAfile);
  Curl_safefree(sslc->CApath);
  Curl_safefree(sslc->cipher_list);
  Curl_safefree(sslc->egdsocket);
  Curl_safefree(sslc->random_file);
  Curl_safefree(sslc->clientcert);
}


/*
 * Curl_rand() returns a random unsigned integer, 32bit.
 *
 * This non-SSL function is put here only because this file is the only one
 * with knowledge of what the underlying SSL libraries provide in terms of
 * randomizers.
 *
 * NOTE: 'data' may be passed in as NULL when coming from external API without
 * easy handle!
 *
 */

unsigned int Curl_rand(struct Curl_easy *data)
{
  unsigned int r = 0;
  static unsigned int randseed;
  static bool seeded = FALSE;

#ifdef CURLDEBUG
  char *force_entropy = getenv("CURL_ENTROPY");
  if(force_entropy) {
    if(!seeded) {
      size_t elen = strlen(force_entropy);
      size_t clen = sizeof(randseed);
      size_t min = elen < clen ? elen : clen;
      memcpy((char *)&randseed, force_entropy, min);
      seeded = TRUE;
    }
    else
      randseed++;
    return randseed;
  }
#endif

  /* data may be NULL! */
  if(!Curl_ssl_random(data, (unsigned char *)&r, sizeof(r)))
    return r;

  /* If Curl_ssl_random() returns non-zero it couldn't offer randomness and we
     instead perform a "best effort" */

#ifdef RANDOM_FILE
  if(!seeded) {
    /* if there's a random file to read a seed from, use it */
    int fd = open(RANDOM_FILE, O_RDONLY);
    if(fd > -1) {
      /* read random data into the randseed variable */
      ssize_t nread = read(fd, &randseed, sizeof(randseed));
      if(nread == sizeof(randseed))
        seeded = TRUE;
      close(fd);
    }
  }
#endif

  if(!seeded) {
    struct timeval now = curlx_tvnow();
    infof(data, "WARNING: Using weak random seed\n");
    randseed += (unsigned int)now.tv_usec + (unsigned int)now.tv_sec;
    randseed = randseed * 1103515245 + 12345;
    randseed = randseed * 1103515245 + 12345;
    randseed = randseed * 1103515245 + 12345;
    seeded = TRUE;
  }

  /* Return an unsigned 32-bit pseudo-random number. */
  r = randseed = randseed * 1103515245 + 12345;
  return (r << 16) | ((r >> 16) & 0xFFFF);
}

int Curl_ssl_backend(void)
{
  return (int)CURL_SSL_BACKEND;
}

#ifdef USE_SSL

/* "global" init done? */
static bool init_ssl=FALSE;

/**
 * Global SSL init
 *
 * @retval 0 error initializing SSL
 * @retval 1 SSL initialized successfully
 */
int Curl_ssl_init(void)
{
  /* make sure this is only done once */
  if(init_ssl)
    return 1;
  init_ssl = TRUE; /* never again */

  return curlssl_init();
}


/* Global cleanup */
void Curl_ssl_cleanup(void)
{
  if(init_ssl) {
    /* only cleanup if we did a previous init */
    curlssl_cleanup();
    init_ssl = FALSE;
  }
}

static bool ssl_prefs_check(struct Curl_easy *data)
{
  /* check for CURLOPT_SSLVERSION invalid parameter value */
  if((data->set.ssl.version < 0)
     || (data->set.ssl.version >= CURL_SSLVERSION_LAST)) {
    failf(data, "Unrecognized parameter value passed via CURLOPT_SSLVERSION");
    return FALSE;
  }
  return TRUE;
}

CURLcode
Curl_ssl_connect(struct connectdata *conn, int sockindex)
{
  CURLcode result;

  if(!ssl_prefs_check(conn->data))
    return CURLE_SSL_CONNECT_ERROR;

  /* mark this is being ssl-enabled from here on. */
  conn->ssl[sockindex].use = TRUE;
  conn->ssl[sockindex].state = ssl_connection_negotiating;

  result = curlssl_connect(conn, sockindex);

  if(!result)
    Curl_pgrsTime(conn->data, TIMER_APPCONNECT); /* SSL is connected */

  return result;
}

CURLcode
Curl_ssl_connect_nonblocking(struct connectdata *conn, int sockindex,
                             bool *done)
{
  CURLcode result;

  if(!ssl_prefs_check(conn->data))
    return CURLE_SSL_CONNECT_ERROR;

  /* mark this is being ssl requested from here on. */
  conn->ssl[sockindex].use = TRUE;
#ifdef curlssl_connect_nonblocking
  result = curlssl_connect_nonblocking(conn, sockindex, done);
#else
  *done = TRUE; /* fallback to BLOCKING */
  result = curlssl_connect(conn, sockindex);
#endif /* non-blocking connect support */
  if(!result && *done)
    Curl_pgrsTime(conn->data, TIMER_APPCONNECT); /* SSL is connected */
  return result;
}

/*
 * Lock shared SSL session data
 */
void Curl_ssl_sessionid_lock(struct connectdata *conn)
{
  if(SSLSESSION_SHARED(conn->data))
    Curl_share_lock(conn->data,
                    CURL_LOCK_DATA_SSL_SESSION, CURL_LOCK_ACCESS_SINGLE);
}

/*
 * Unlock shared SSL session data
 */
void Curl_ssl_sessionid_unlock(struct connectdata *conn)
{
  if(SSLSESSION_SHARED(conn->data))
    Curl_share_unlock(conn->data, CURL_LOCK_DATA_SSL_SESSION);
}

/*
 * Check if there's a session ID for the given connection in the cache, and if
 * there's one suitable, it is provided. Returns TRUE when no entry matched.
 */
bool Curl_ssl_getsessionid(struct connectdata *conn,
                           void **ssl_sessionid,
                           size_t *idsize) /* set 0 if unknown */
{
  struct curl_ssl_session *check;
  struct Curl_easy *data = conn->data;
  size_t i;
  long *general_age;
  bool no_match = TRUE;

  *ssl_sessionid = NULL;

  DEBUGASSERT(conn->ssl_config.sessionid);

  if(!conn->ssl_config.sessionid)
    /* session ID re-use is disabled */
    return TRUE;

  /* Lock if shared */
  if(SSLSESSION_SHARED(data))
    general_age = &data->share->sessionage;
  else
    general_age = &data->state.sessionage;

  for(i = 0; i < data->set.ssl.max_ssl_sessions; i++) {
    check = &data->state.session[i];
    if(!check->sessionid)
      /* not session ID means blank entry */
      continue;
    if(Curl_raw_equal(conn->host.name, check->name) &&
       ((!conn->bits.conn_to_host && !check->conn_to_host) ||
         (conn->bits.conn_to_host && check->conn_to_host &&
           Curl_raw_equal(conn->conn_to_host.name, check->conn_to_host))) &&
       ((!conn->bits.conn_to_port && check->conn_to_port == -1) ||
         (conn->bits.conn_to_port && check->conn_to_port != -1 &&
           conn->conn_to_port == check->conn_to_port)) &&
       (conn->remote_port == check->remote_port) &&
       Curl_ssl_config_matches(&conn->ssl_config, &check->ssl_config)) {
      /* yes, we have a session ID! */
      (*general_age)++;          /* increase general age */
      check->age = *general_age; /* set this as used in this age */
      *ssl_sessionid = check->sessionid;
      if(idsize)
        *idsize = check->idsize;
      no_match = FALSE;
      break;
    }
  }

  return no_match;
}

/*
 * Kill a single session ID entry in the cache.
 */
void Curl_ssl_kill_session(struct curl_ssl_session *session)
{
  if(session->sessionid) {
    /* defensive check */

    /* free the ID the SSL-layer specific way */
    curlssl_session_free(session->sessionid);

    session->sessionid = NULL;
    session->age = 0; /* fresh */

    Curl_free_ssl_config(&session->ssl_config);

    Curl_safefree(session->name);
    Curl_safefree(session->conn_to_host);
  }
}

/*
 * Delete the given session ID from the cache.
 */
void Curl_ssl_delsessionid(struct connectdata *conn, void *ssl_sessionid)
{
  size_t i;
  struct Curl_easy *data=conn->data;

  for(i = 0; i < data->set.ssl.max_ssl_sessions; i++) {
    struct curl_ssl_session *check = &data->state.session[i];

    if(check->sessionid == ssl_sessionid) {
      Curl_ssl_kill_session(check);
      break;
    }
  }
}

/*
 * Store session id in the session cache. The ID passed on to this function
 * must already have been extracted and allocated the proper way for the SSL
 * layer. Curl_XXXX_session_free() will be called to free/kill the session ID
 * later on.
 */
CURLcode Curl_ssl_addsessionid(struct connectdata *conn,
                               void *ssl_sessionid,
                               size_t idsize)
{
  size_t i;
  struct Curl_easy *data=conn->data; /* the mother of all structs */
  struct curl_ssl_session *store = &data->state.session[0];
  long oldest_age=data->state.session[0].age; /* zero if unused */
  char *clone_host;
  char *clone_conn_to_host;
  int conn_to_port;
  long *general_age;

  DEBUGASSERT(conn->ssl_config.sessionid);

  clone_host = strdup(conn->host.name);
  if(!clone_host)
    return CURLE_OUT_OF_MEMORY; /* bail out */

  if(conn->bits.conn_to_host) {
    clone_conn_to_host = strdup(conn->conn_to_host.name);
    if(!clone_conn_to_host) {
      free(clone_host);
      return CURLE_OUT_OF_MEMORY; /* bail out */
    }
  }
  else
    clone_conn_to_host = NULL;

  if(conn->bits.conn_to_port)
    conn_to_port = conn->conn_to_port;
  else
    conn_to_port = -1;

  /* Now we should add the session ID and the host name to the cache, (remove
     the oldest if necessary) */

  /* If using shared SSL session, lock! */
  if(SSLSESSION_SHARED(data)) {
    general_age = &data->share->sessionage;
  }
  else {
    general_age = &data->state.sessionage;
  }

  /* find an empty slot for us, or find the oldest */
  for(i = 1; (i < data->set.ssl.max_ssl_sessions) &&
        data->state.session[i].sessionid; i++) {
    if(data->state.session[i].age < oldest_age) {
      oldest_age = data->state.session[i].age;
      store = &data->state.session[i];
    }
  }
  if(i == data->set.ssl.max_ssl_sessions)
    /* cache is full, we must "kill" the oldest entry! */
    Curl_ssl_kill_session(store);
  else
    store = &data->state.session[i]; /* use this slot */

  /* now init the session struct wisely */
  store->sessionid = ssl_sessionid;
  store->idsize = idsize;
  store->age = *general_age;    /* set current age */
    /* free it if there's one already present */
  free(store->name);
  free(store->conn_to_host);
  store->name = clone_host;               /* clone host name */
  store->conn_to_host = clone_conn_to_host; /* clone connect to host name */
  store->conn_to_port = conn_to_port; /* connect to port number */
  store->remote_port = conn->remote_port; /* port number */

  if(!Curl_clone_ssl_config(&conn->ssl_config, &store->ssl_config)) {
    store->sessionid = NULL; /* let caller free sessionid */
    free(clone_host);
    free(clone_conn_to_host);
    return CURLE_OUT_OF_MEMORY;
  }

  return CURLE_OK;
}


void Curl_ssl_close_all(struct Curl_easy *data)
{
  size_t i;
  /* kill the session ID cache if not shared */
  if(data->state.session && !SSLSESSION_SHARED(data)) {
    for(i = 0; i < data->set.ssl.max_ssl_sessions; i++)
      /* the single-killer function handles empty table slots */
      Curl_ssl_kill_session(&data->state.session[i]);

    /* free the cache data */
    Curl_safefree(data->state.session);
  }

  curlssl_close_all(data);
}

void Curl_ssl_close(struct connectdata *conn, int sockindex)
{
  DEBUGASSERT((sockindex <= 1) && (sockindex >= -1));
  curlssl_close(conn, sockindex);
}

CURLcode Curl_ssl_shutdown(struct connectdata *conn, int sockindex)
{
  if(curlssl_shutdown(conn, sockindex))
    return CURLE_SSL_SHUTDOWN_FAILED;

  conn->ssl[sockindex].use = FALSE; /* get back to ordinary socket usage */
  conn->ssl[sockindex].state = ssl_connection_none;

  conn->recv[sockindex] = Curl_recv_plain;
  conn->send[sockindex] = Curl_send_plain;

  return CURLE_OK;
}

/* Selects an SSL crypto engine
 */
CURLcode Curl_ssl_set_engine(struct Curl_easy *data, const char *engine)
{
  return curlssl_set_engine(data, engine);
}

/* Selects the default SSL crypto engine
 */
CURLcode Curl_ssl_set_engine_default(struct Curl_easy *data)
{
  return curlssl_set_engine_default(data);
}

/* Return list of OpenSSL crypto engine names. */
struct curl_slist *Curl_ssl_engines_list(struct Curl_easy *data)
{
  return curlssl_engines_list(data);
}

/*
 * This sets up a session ID cache to the specified size. Make sure this code
 * is agnostic to what underlying SSL technology we use.
 */
CURLcode Curl_ssl_initsessions(struct Curl_easy *data, size_t amount)
{
  struct curl_ssl_session *session;

  if(data->state.session)
    /* this is just a precaution to prevent multiple inits */
    return CURLE_OK;

  session = calloc(amount, sizeof(struct curl_ssl_session));
  if(!session)
    return CURLE_OUT_OF_MEMORY;

  /* store the info in the SSL section */
  data->set.ssl.max_ssl_sessions = amount;
  data->state.session = session;
  data->state.sessionage = 1; /* this is brand new */
  return CURLE_OK;
}

size_t Curl_ssl_version(char *buffer, size_t size)
{
  return curlssl_version(buffer, size);
}

/*
 * This function tries to determine connection status.
 *
 * Return codes:
 *     1 means the connection is still in place
 *     0 means the connection has been closed
 *    -1 means the connection status is unknown
 */
int Curl_ssl_check_cxn(struct connectdata *conn)
{
  return curlssl_check_cxn(conn);
}

bool Curl_ssl_data_pending(const struct connectdata *conn,
                           int connindex)
{
  return curlssl_data_pending(conn, connindex);
}

void Curl_ssl_free_certinfo(struct Curl_easy *data)
{
  int i;
  struct curl_certinfo *ci = &data->info.certs;

  if(ci->num_of_certs) {
    /* free all individual lists used */
    for(i=0; i<ci->num_of_certs; i++) {
      curl_slist_free_all(ci->certinfo[i]);
      ci->certinfo[i] = NULL;
    }

    free(ci->certinfo); /* free the actual array too */
    ci->certinfo = NULL;
    ci->num_of_certs = 0;
  }
}

CURLcode Curl_ssl_init_certinfo(struct Curl_easy *data, int num)
{
  struct curl_certinfo *ci = &data->info.certs;
  struct curl_slist **table;

  /* Free any previous certificate information structures */
  Curl_ssl_free_certinfo(data);

  /* Allocate the required certificate information structures */
  table = calloc((size_t) num, sizeof(struct curl_slist *));
  if(!table)
    return CURLE_OUT_OF_MEMORY;

  ci->num_of_certs = num;
  ci->certinfo = table;

  return CURLE_OK;
}

/*
 * 'value' is NOT a zero terminated string
 */
CURLcode Curl_ssl_push_certinfo_len(struct Curl_easy *data,
                                    int certnum,
                                    const char *label,
                                    const char *value,
                                    size_t valuelen)
{
  struct curl_certinfo * ci = &data->info.certs;
  char * output;
  struct curl_slist * nl;
  CURLcode result = CURLE_OK;
  size_t labellen = strlen(label);
  size_t outlen = labellen + 1 + valuelen + 1; /* label:value\0 */

  output = malloc(outlen);
  if(!output)
    return CURLE_OUT_OF_MEMORY;

  /* sprintf the label and colon */
  snprintf(output, outlen, "%s:", label);

  /* memcpy the value (it might not be zero terminated) */
  memcpy(&output[labellen+1], value, valuelen);

  /* zero terminate the output */
  output[labellen + 1 + valuelen] = 0;

  nl = Curl_slist_append_nodup(ci->certinfo[certnum], output);
  if(!nl) {
    free(output);
    curl_slist_free_all(ci->certinfo[certnum]);
    result = CURLE_OUT_OF_MEMORY;
  }

  ci->certinfo[certnum] = nl;
  return result;
}

/*
 * This is a convenience function for push_certinfo_len that takes a zero
 * terminated value.
 */
CURLcode Curl_ssl_push_certinfo(struct Curl_easy *data,
                                int certnum,
                                const char *label,
                                const char *value)
{
  size_t valuelen = strlen(value);

  return Curl_ssl_push_certinfo_len(data, certnum, label, value, valuelen);
}

int Curl_ssl_random(struct Curl_easy *data,
                     unsigned char *entropy,
                     size_t length)
{
  return curlssl_random(data, entropy, length);
}

/*
 * Public key pem to der conversion
 */

static CURLcode pubkey_pem_to_der(const char *pem,
                                  unsigned char **der, size_t *der_len)
{
  char *stripped_pem, *begin_pos, *end_pos;
  size_t pem_count, stripped_pem_count = 0, pem_len;
  CURLcode result;

  /* if no pem, exit. */
  if(!pem)
    return CURLE_BAD_CONTENT_ENCODING;

  begin_pos = strstr(pem, "-----BEGIN PUBLIC KEY-----");
  if(!begin_pos)
    return CURLE_BAD_CONTENT_ENCODING;

  pem_count = begin_pos - pem;
  /* Invalid if not at beginning AND not directly following \n */
  if(0 != pem_count && '\n' != pem[pem_count - 1])
    return CURLE_BAD_CONTENT_ENCODING;

  /* 26 is length of "-----BEGIN PUBLIC KEY-----" */
  pem_count += 26;

  /* Invalid if not directly following \n */
  end_pos = strstr(pem + pem_count, "\n-----END PUBLIC KEY-----");
  if(!end_pos)
    return CURLE_BAD_CONTENT_ENCODING;

  pem_len = end_pos - pem;

  stripped_pem = malloc(pem_len - pem_count + 1);
  if(!stripped_pem)
    return CURLE_OUT_OF_MEMORY;

  /*
   * Here we loop through the pem array one character at a time between the
   * correct indices, and place each character that is not '\n' or '\r'
   * into the stripped_pem array, which should represent the raw base64 string
   */
  while(pem_count < pem_len) {
    if('\n' != pem[pem_count] && '\r' != pem[pem_count])
      stripped_pem[stripped_pem_count++] = pem[pem_count];
    ++pem_count;
  }
  /* Place the null terminator in the correct place */
  stripped_pem[stripped_pem_count] = '\0';

  result = Curl_base64_decode(stripped_pem, der, der_len);

  Curl_safefree(stripped_pem);

  return result;
}

/*
 * Generic pinned public key check.
 */

CURLcode Curl_pin_peer_pubkey(struct Curl_easy *data,
                              const char *pinnedpubkey,
                              const unsigned char *pubkey, size_t pubkeylen)
{
  FILE *fp;
  unsigned char *buf = NULL, *pem_ptr = NULL;
  long filesize;
  size_t size, pem_len;
  CURLcode pem_read;
  CURLcode result = CURLE_SSL_PINNEDPUBKEYNOTMATCH;
#ifdef curlssl_sha256sum
  CURLcode encode;
  size_t encodedlen, pinkeylen;
  char *encoded, *pinkeycopy, *begin_pos, *end_pos;
  unsigned char *sha256sumdigest = NULL;
#endif

  /* if a path wasn't specified, don't pin */
  if(!pinnedpubkey)
    return CURLE_OK;
  if(!pubkey || !pubkeylen)
    return result;

  /* only do this if pinnedpubkey starts with "sha256//", length 8 */
  if(strncmp(pinnedpubkey, "sha256//", 8) == 0) {
#ifdef curlssl_sha256sum
    /* compute sha256sum of public key */
    sha256sumdigest = malloc(SHA256_DIGEST_LENGTH);
    if(!sha256sumdigest)
      return CURLE_OUT_OF_MEMORY;
    curlssl_sha256sum(pubkey, pubkeylen,
                      sha256sumdigest, SHA256_DIGEST_LENGTH);
    encode = Curl_base64_encode(data, (char *)sha256sumdigest,
                                SHA256_DIGEST_LENGTH, &encoded, &encodedlen);
    Curl_safefree(sha256sumdigest);

    if(encode)
      return encode;

    infof(data, "\t public key hash: sha256//%s\n", encoded);

    /* it starts with sha256//, copy so we can modify it */
    pinkeylen = strlen(pinnedpubkey) + 1;
    pinkeycopy = malloc(pinkeylen);
    if(!pinkeycopy) {
      Curl_safefree(encoded);
      return CURLE_OUT_OF_MEMORY;
    }
    memcpy(pinkeycopy, pinnedpubkey, pinkeylen);
    /* point begin_pos to the copy, and start extracting keys */
    begin_pos = pinkeycopy;
    do {
      end_pos = strstr(begin_pos, ";sha256//");
      /*
       * if there is an end_pos, null terminate,
       * otherwise it'll go to the end of the original string
       */
      if(end_pos)
        end_pos[0] = '\0';

      /* compare base64 sha256 digests, 8 is the length of "sha256//" */
      if(encodedlen == strlen(begin_pos + 8) &&
         !memcmp(encoded, begin_pos + 8, encodedlen)) {
        result = CURLE_OK;
        break;
      }

      /*
       * change back the null-terminator we changed earlier,
       * and look for next begin
       */
      if(end_pos) {
        end_pos[0] = ';';
        begin_pos = strstr(end_pos, "sha256//");
      }
    } while(end_pos && begin_pos);
    Curl_safefree(encoded);
    Curl_safefree(pinkeycopy);
#else
    /* without sha256 support, this cannot match */
    (void)data;
#endif
    return result;
  }

  fp = fopen(pinnedpubkey, "rb");
  if(!fp)
    return result;

  do {
    /* Determine the file's size */
    if(fseek(fp, 0, SEEK_END))
      break;
    filesize = ftell(fp);
    if(fseek(fp, 0, SEEK_SET))
      break;
    if(filesize < 0 || filesize > MAX_PINNED_PUBKEY_SIZE)
      break;

    /*
     * if the size of our certificate is bigger than the file
     * size then it can't match
     */
    size = curlx_sotouz((curl_off_t) filesize);
    if(pubkeylen > size)
      break;

    /*
     * Allocate buffer for the pinned key
     * With 1 additional byte for null terminator in case of PEM key
     */
    buf = malloc(size + 1);
    if(!buf)
      break;

    /* Returns number of elements read, which should be 1 */
    if((int) fread(buf, size, 1, fp) != 1)
      break;

    /* If the sizes are the same, it can't be base64 encoded, must be der */
    if(pubkeylen == size) {
      if(!memcmp(pubkey, buf, pubkeylen))
        result = CURLE_OK;
      break;
    }

    /*
     * Otherwise we will assume it's PEM and try to decode it
     * after placing null terminator
     */
    buf[size] = '\0';
    pem_read = pubkey_pem_to_der((const char *)buf, &pem_ptr, &pem_len);
    /* if it wasn't read successfully, exit */
    if(pem_read)
      break;

    /*
     * if the size of our certificate doesn't match the size of
     * the decoded file, they can't be the same, otherwise compare
     */
    if(pubkeylen == pem_len && !memcmp(pubkey, pem_ptr, pubkeylen))
      result = CURLE_OK;
  } while(0);

  Curl_safefree(buf);
  Curl_safefree(pem_ptr);
  fclose(fp);

  return result;
}

#ifndef CURL_DISABLE_CRYPTO_AUTH
CURLcode Curl_ssl_md5sum(unsigned char *tmp, /* input */
                         size_t tmplen,
                         unsigned char *md5sum, /* output */
                         size_t md5len)
{
#ifdef curlssl_md5sum
  curlssl_md5sum(tmp, tmplen, md5sum, md5len);
#else
  MD5_context *MD5pw;

  (void) md5len;

  MD5pw = Curl_MD5_init(Curl_DIGEST_MD5);
  if(!MD5pw)
    return CURLE_OUT_OF_MEMORY;
  Curl_MD5_update(MD5pw, tmp, curlx_uztoui(tmplen));
  Curl_MD5_final(MD5pw, md5sum);
#endif
  return CURLE_OK;
}
#endif

/*
 * Check whether the SSL backend supports the status_request extension.
 */
bool Curl_ssl_cert_status_request(void)
{
#ifdef curlssl_cert_status_request
  return curlssl_cert_status_request();
#else
  return FALSE;
#endif
}

/*
 * Check whether the SSL backend supports false start.
 */
bool Curl_ssl_false_start(void)
{
#ifdef curlssl_false_start
  return curlssl_false_start();
#else
  return FALSE;
#endif
}

#endif /* USE_SSL */