Coverage Report

Created: 2025-07-01 06:46

/src/FreeRDP/libfreerdp/crypto/x509_utils.c
Line
Count
Source (jump to first uncovered line)
1
/**
2
 * FreeRDP: A Remote Desktop Protocol Implementation
3
 * Cryptographic Abstraction Layer
4
 *
5
 * Copyright 2011-2012 Marc-Andre Moreau <marcandre.moreau@gmail.com>
6
 * Copyright 2023 Armin Novak <anovak@thincast.com>
7
 * Copyright 2023 Thincast Technologies GmbH
8
 *
9
 * Licensed under the Apache License, Version 2.0 (the "License");
10
 * you may not use this file except in compliance with the License.
11
 * You may obtain a copy of the License at
12
 *
13
 *   http://www.apache.org/licenses/LICENSE-2.0
14
 *
15
 * Unless required by applicable law or agreed to in writing, software
16
 * distributed under the License is distributed on an "AS IS" BASIS,
17
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
18
 * See the License for the specific language governing permissions and
19
 * limitations under the License.
20
 */
21
22
#include <openssl/objects.h>
23
#include <openssl/x509v3.h>
24
#include <openssl/pem.h>
25
#include <openssl/err.h>
26
27
#include <freerdp/config.h>
28
29
#include <winpr/crt.h>
30
#include <winpr/string.h>
31
#include <winpr/assert.h>
32
33
#include <freerdp/log.h>
34
35
#include "x509_utils.h"
36
37
#define TAG FREERDP_TAG("crypto")
38
39
BYTE* x509_utils_get_hash(const X509* xcert, const char* hash, size_t* length)
40
0
{
41
0
  UINT32 fp_len = EVP_MAX_MD_SIZE;
42
0
  BYTE* fp = NULL;
43
0
  const EVP_MD* md = EVP_get_digestbyname(hash);
44
0
  if (!md)
45
0
  {
46
0
    WLog_ERR(TAG, "System does not support %s hash!", hash);
47
0
    return NULL;
48
0
  }
49
0
  if (!xcert || !length)
50
0
  {
51
0
    WLog_ERR(TAG, "Invalid arguments: xcert=%p, length=%p", xcert, length);
52
0
    return NULL;
53
0
  }
54
55
0
  fp = calloc(fp_len + 1, sizeof(BYTE));
56
0
  if (!fp)
57
0
  {
58
0
    WLog_ERR(TAG, "could not allocate %" PRIuz " bytes", fp_len);
59
0
    return NULL;
60
0
  }
61
62
0
  if (X509_digest(xcert, md, fp, &fp_len) != 1)
63
0
  {
64
0
    free(fp);
65
0
    WLog_ERR(TAG, "certificate does not have a %s hash!", hash);
66
0
    return NULL;
67
0
  }
68
69
0
  *length = fp_len;
70
0
  return fp;
71
0
}
72
73
static char* crypto_print_name(const X509_NAME* name)
74
0
{
75
0
  char* buffer = NULL;
76
0
  BIO* outBIO = BIO_new(BIO_s_mem());
77
78
0
  if (X509_NAME_print_ex(outBIO, name, 0, XN_FLAG_ONELINE) > 0)
79
0
  {
80
0
    UINT64 size = BIO_number_written(outBIO);
81
0
    if (size > INT_MAX)
82
0
      goto fail;
83
0
    buffer = calloc(1, (size_t)size + 1);
84
85
0
    if (!buffer)
86
0
      goto fail;
87
88
0
    ERR_clear_error();
89
0
    const int rc = BIO_read(outBIO, buffer, (int)size);
90
0
    if (rc <= 0)
91
0
    {
92
0
      free(buffer);
93
0
      buffer = NULL;
94
0
      goto fail;
95
0
    }
96
0
  }
97
98
0
fail:
99
0
  BIO_free_all(outBIO);
100
0
  return buffer;
101
0
}
102
103
char* x509_utils_get_subject(const X509* xcert)
104
0
{
105
0
  char* subject = NULL;
106
0
  if (!xcert)
107
0
  {
108
0
    WLog_ERR(TAG, "Invalid certificate %p", xcert);
109
0
    return NULL;
110
0
  }
111
0
  subject = crypto_print_name(X509_get_subject_name(xcert));
112
0
  if (!subject)
113
0
    WLog_WARN(TAG, "certificate does not have a subject!");
114
0
  return subject;
115
0
}
116
117
/* GENERAL_NAME type labels */
118
119
static const char* general_name_type_labels[] = { "OTHERNAME", "EMAIL    ", "DNS      ",
120
                                                "X400     ", "DIRNAME  ", "EDIPARTY ",
121
                                                "URI      ", "IPADD    ", "RID      " };
122
123
static const char* general_name_type_label(int general_name_type)
124
0
{
125
0
  if ((0 <= general_name_type) &&
126
0
      ((size_t)general_name_type < ARRAYSIZE(general_name_type_labels)))
127
0
  {
128
0
    return general_name_type_labels[general_name_type];
129
0
  }
130
0
  else
131
0
  {
132
0
    static char buffer[80] = { 0 };
133
0
    (void)snprintf(buffer, sizeof(buffer), "Unknown general name type (%d)", general_name_type);
134
0
    return buffer;
135
0
  }
136
0
}
137
138
/*
139
140
map_subject_alt_name(x509,  general_name_type, mapper, data)
141
142
Call the function mapper with subjectAltNames found in the x509
143
certificate and data.  if generate_name_type is GEN_ALL,  the the
144
mapper is called for all the names,  else it's called only for names
145
of the given type.
146
147
148
We implement two extractors:
149
150
 -  a string extractor that can be used to get the subjectAltNames of
151
    the following types: GEN_URI,  GEN_DNS,  GEN_EMAIL
152
153
 - a ASN1_OBJECT filter/extractor that can be used to get the
154
   subjectAltNames of OTHERNAME type.
155
156
   Note: usually, it's a string, but some type of otherNames can be
157
   associated with different classes of objects. eg. a KPN may be a
158
   sequence of realm and principal name, instead of a single string
159
   object.
160
161
Not implemented yet: extractors for the types: GEN_X400, GEN_DIRNAME,
162
GEN_EDIPARTY, GEN_RID, GEN_IPADD (the later can contain nul-bytes).
163
164
165
mapper(name, data, index, count)
166
167
The mapper is passed:
168
 - the GENERAL_NAME selected,
169
 - the data,
170
 - the index of the general name in the subjectAltNames,
171
 - the total number of names in the subjectAltNames.
172
173
The last parameter let's the mapper allocate arrays to collect objects.
174
Note: if names are filtered,  not all the indices from 0 to count-1 are
175
passed to mapper,  only the indices selected.
176
177
When the mapper returns 0, map_subject_alt_name stops the iteration immediately.
178
179
*/
180
181
0
#define GEN_ALL (-1)
182
183
typedef int (*general_name_mapper_pr)(GENERAL_NAME* name, void* data, int index, int count);
184
185
static void map_subject_alt_name(const X509* x509, int general_name_type,
186
                                 general_name_mapper_pr mapper, void* data)
187
0
{
188
0
  int num = 0;
189
0
  STACK_OF(GENERAL_NAME)* gens = NULL;
190
0
  gens = X509_get_ext_d2i(x509, NID_subject_alt_name, NULL, NULL);
191
192
0
  if (!gens)
193
0
  {
194
0
    return;
195
0
  }
196
197
0
  num = sk_GENERAL_NAME_num(gens);
198
199
0
  for (int i = 0; (i < num); i++)
200
0
  {
201
0
    GENERAL_NAME* name = sk_GENERAL_NAME_value(gens, i);
202
203
0
    if (name)
204
0
    {
205
0
      if ((general_name_type == GEN_ALL) || (general_name_type == name->type))
206
0
      {
207
0
        if (!mapper(name, data, i, num))
208
0
        {
209
0
          break;
210
0
        }
211
0
      }
212
0
    }
213
0
  }
214
215
0
  sk_GENERAL_NAME_pop_free(gens, GENERAL_NAME_free);
216
0
}
217
218
/*
219
extract_string  --  string extractor
220
221
- the strings array is allocated lazily, when we first have to store a
222
  string.
223
224
- allocated contains the size of the strings array, or -1 if
225
  allocation failed.
226
227
- count contains the actual count of strings in the strings array.
228
229
- maximum limits the number of strings we can store in the strings
230
  array: beyond, the extractor returns 0 to short-cut the search.
231
232
extract_string stores in the string list OPENSSL strings,
233
that must be freed with OPENSSL_free.
234
235
*/
236
237
typedef struct string_list
238
{
239
  char** strings;
240
  size_t allocated;
241
  size_t count;
242
  size_t maximum;
243
} string_list;
244
245
static void string_list_initialize(string_list* list)
246
0
{
247
0
  list->strings = 0;
248
0
  list->allocated = 0;
249
0
  list->count = 0;
250
0
  list->maximum = INT_MAX;
251
0
}
252
253
static void string_list_allocate(string_list* list, size_t allocate_count)
254
0
{
255
0
  if (!list->strings && list->allocated == 0)
256
0
  {
257
0
    list->strings = (char**)calloc(allocate_count, sizeof(char*));
258
0
    list->allocated = list->strings ? allocate_count : 0;
259
0
    list->count = 0;
260
0
  }
261
0
}
262
263
static void string_list_free(string_list* list)
264
0
{
265
  /* Note: we don't free the contents of the strings array: this */
266
  /* is handled by the caller,  either by returning this */
267
  /* content,  or freeing it itself. */
268
0
  free((void*)list->strings);
269
0
}
270
271
static int extract_string(GENERAL_NAME* name, void* data, int index, int count)
272
0
{
273
0
  string_list* list = data;
274
0
  unsigned char* cstring = 0;
275
0
  ASN1_STRING* str = NULL;
276
277
0
  WINPR_UNUSED(index);
278
279
0
  switch (name->type)
280
0
  {
281
0
    case GEN_URI:
282
0
      str = name->d.uniformResourceIdentifier;
283
0
      break;
284
285
0
    case GEN_DNS:
286
0
      str = name->d.dNSName;
287
0
      break;
288
289
0
    case GEN_EMAIL:
290
0
      str = name->d.rfc822Name;
291
0
      break;
292
293
0
    default:
294
0
      return 1;
295
0
  }
296
297
0
  if ((ASN1_STRING_to_UTF8(&cstring, str)) < 0)
298
0
  {
299
0
    WLog_ERR(TAG, "ASN1_STRING_to_UTF8() failed for %s: %s",
300
0
             general_name_type_label(name->type), ERR_error_string(ERR_get_error(), NULL));
301
0
    return 1;
302
0
  }
303
304
0
  string_list_allocate(list, WINPR_ASSERTING_INT_CAST(WINPR_CIPHER_TYPE, count));
305
306
0
  if (list->allocated <= 0)
307
0
  {
308
0
    OPENSSL_free(cstring);
309
0
    return 0;
310
0
  }
311
312
0
  list->strings[list->count] = (char*)cstring;
313
0
  list->count++;
314
315
0
  if (list->count >= list->maximum)
316
0
  {
317
0
    return 0;
318
0
  }
319
320
0
  return 1;
321
0
}
322
323
/*
324
extract_othername_object --  object extractor.
325
326
- the objects array is allocated lazily, when we first have to store a
327
  string.
328
329
- allocated contains the size of the objects array, or -1 if
330
  allocation failed.
331
332
- count contains the actual count of objects in the objects array.
333
334
- maximum limits the number of objects we can store in the objects
335
  array: beyond, the extractor returns 0 to short-cut the search.
336
337
extract_othername_objects stores in the objects array ASN1_TYPE *
338
pointers directly obtained from the GENERAL_NAME.
339
*/
340
341
typedef struct object_list
342
{
343
  ASN1_OBJECT* type_id;
344
  char** strings;
345
  size_t allocated;
346
  size_t count;
347
  size_t maximum;
348
} object_list;
349
350
static void object_list_initialize(object_list* list)
351
0
{
352
0
  list->type_id = 0;
353
0
  list->strings = 0;
354
0
  list->allocated = 0;
355
0
  list->count = 0;
356
0
  list->maximum = INT_MAX;
357
0
}
358
359
static void object_list_allocate(object_list* list, size_t allocate_count)
360
0
{
361
0
  if (!list->strings && (list->allocated == 0) && (allocate_count > 0))
362
0
  {
363
0
    list->strings = (char**)calloc(allocate_count, sizeof(list->strings[0]));
364
0
    list->allocated = list->strings ? allocate_count : 0;
365
0
    list->count = 0;
366
0
  }
367
0
}
368
369
static char* object_string(ASN1_TYPE* object)
370
0
{
371
0
  char* result = NULL;
372
0
  unsigned char* utf8String = NULL;
373
374
  /* TODO: check that object.type is a string type. */
375
0
  const int length = ASN1_STRING_to_UTF8(&utf8String, object->value.asn1_string);
376
377
0
  if (length < 0)
378
0
  {
379
0
    return 0;
380
0
  }
381
382
0
  result = strndup((char*)utf8String, WINPR_ASSERTING_INT_CAST(size_t, length));
383
0
  OPENSSL_free(utf8String);
384
0
  return result;
385
0
}
386
387
static void object_list_free(object_list* list)
388
0
{
389
0
  WINPR_ASSERT(list);
390
0
  free((void*)list->strings);
391
0
}
392
393
static int extract_othername_object_as_string(GENERAL_NAME* name, void* data, int index, int count)
394
0
{
395
0
  object_list* list = data;
396
0
  WINPR_UNUSED(index);
397
398
0
  if (count < 0)
399
0
    return -1;
400
401
0
  if (name->type != GEN_OTHERNAME)
402
0
  {
403
0
    return 1;
404
0
  }
405
406
0
  if (0 != OBJ_cmp(name->d.otherName->type_id, list->type_id))
407
0
  {
408
0
    return 1;
409
0
  }
410
411
0
  object_list_allocate(list, WINPR_ASSERTING_INT_CAST(size_t, count));
412
413
0
  if (list->allocated <= 0)
414
0
  {
415
0
    return 0;
416
0
  }
417
418
0
  list->strings[list->count] = object_string(name->d.otherName->value);
419
420
0
  if (list->strings[list->count])
421
0
  {
422
0
    list->count++;
423
0
  }
424
425
0
  if (list->count >= list->maximum)
426
0
  {
427
0
    return 0;
428
0
  }
429
430
0
  return 1;
431
0
}
432
433
char* x509_utils_get_email(const X509* x509)
434
0
{
435
0
  char* result = 0;
436
0
  string_list list;
437
0
  string_list_initialize(&list);
438
0
  list.maximum = 1;
439
0
  map_subject_alt_name(x509, GEN_EMAIL, extract_string, &list);
440
441
0
  if (list.count == 0)
442
0
  {
443
0
    string_list_free(&list);
444
0
    return 0;
445
0
  }
446
447
0
  result = _strdup(list.strings[0]);
448
0
  OPENSSL_free(list.strings[0]);
449
0
  string_list_free(&list);
450
0
  return result;
451
0
}
452
453
char* x509_utils_get_upn(const X509* x509)
454
0
{
455
0
  char* result = 0;
456
0
  object_list list = { 0 };
457
0
  object_list_initialize(&list);
458
0
  list.type_id = OBJ_nid2obj(NID_ms_upn);
459
0
  list.maximum = 1;
460
0
  map_subject_alt_name(x509, GEN_OTHERNAME, extract_othername_object_as_string, &list);
461
462
0
  if (list.count == 0)
463
0
  {
464
0
    object_list_free(&list);
465
0
    return 0;
466
0
  }
467
468
0
  result = list.strings[0];
469
0
  object_list_free(&list);
470
0
  return result;
471
0
}
472
473
char* x509_utils_get_date(const X509* x509, BOOL startDate)
474
0
{
475
0
  WINPR_ASSERT(x509);
476
477
0
  const ASN1_TIME* date = startDate ? X509_get0_notBefore(x509) : X509_get0_notAfter(x509);
478
0
  if (!date)
479
0
    return NULL;
480
481
0
  BIO* bmem = BIO_new(BIO_s_mem());
482
0
  if (!bmem)
483
0
    return NULL;
484
485
0
  char* str = NULL;
486
0
  if (ASN1_TIME_print(bmem, date))
487
0
  {
488
0
    BUF_MEM* bptr = NULL;
489
490
0
    BIO_get_mem_ptr(bmem, &bptr);
491
0
    str = strndup(bptr->data, bptr->length);
492
0
  }
493
0
  else
494
0
  { // Log error
495
0
  }
496
0
  BIO_free_all(bmem);
497
0
  return str;
498
0
}
499
500
void x509_utils_dns_names_free(size_t count, size_t* lengths, char** dns_names)
501
0
{
502
0
  free(lengths);
503
504
0
  if (dns_names)
505
0
  {
506
0
    for (size_t i = 0; i < count; i++)
507
0
    {
508
0
      if (dns_names[i])
509
0
      {
510
0
        OPENSSL_free(dns_names[i]);
511
0
      }
512
0
    }
513
514
0
    free((void*)dns_names);
515
0
  }
516
0
}
517
518
char** x509_utils_get_dns_names(const X509* x509, size_t* count, size_t** lengths)
519
0
{
520
0
  char** result = 0;
521
0
  string_list list = { 0 };
522
0
  string_list_initialize(&list);
523
0
  map_subject_alt_name(x509, GEN_DNS, extract_string, &list);
524
0
  (*count) = list.count;
525
526
0
  if (list.count <= 0)
527
0
  {
528
0
    string_list_free(&list);
529
0
    return NULL;
530
0
  }
531
532
  /* lengths are not useful,  since we converted the
533
     strings to utf-8,  there cannot be nul-bytes in them. */
534
0
  result = (char**)calloc(list.count, sizeof(*result));
535
0
  (*lengths) = calloc(list.count, sizeof(**lengths));
536
537
0
  if (!result || !(*lengths))
538
0
  {
539
0
    string_list_free(&list);
540
0
    free((void*)result);
541
0
    free(*lengths);
542
0
    (*lengths) = 0;
543
0
    (*count) = 0;
544
0
    return NULL;
545
0
  }
546
547
0
  for (size_t i = 0; i < list.count; i++)
548
0
  {
549
0
    result[i] = list.strings[i];
550
0
    (*lengths)[i] = strlen(result[i]);
551
0
  }
552
553
0
  string_list_free(&list);
554
0
  return result;
555
0
}
556
557
char* x509_utils_get_issuer(const X509* xcert)
558
0
{
559
0
  char* issuer = NULL;
560
0
  if (!xcert)
561
0
  {
562
0
    WLog_ERR(TAG, "Invalid certificate %p", xcert);
563
0
    return NULL;
564
0
  }
565
0
  issuer = crypto_print_name(X509_get_issuer_name(xcert));
566
0
  if (!issuer)
567
0
    WLog_WARN(TAG, "certificate does not have an issuer!");
568
0
  return issuer;
569
0
}
570
571
BOOL x509_utils_check_eku(const X509* xcert, int nid)
572
0
{
573
0
  BOOL ret = FALSE;
574
0
  STACK_OF(ASN1_OBJECT)* oid_stack = NULL;
575
0
  ASN1_OBJECT* oid = NULL;
576
577
0
  if (!xcert)
578
0
    return FALSE;
579
580
0
  oid = OBJ_nid2obj(nid);
581
0
  if (!oid)
582
0
    return FALSE;
583
584
0
  oid_stack = X509_get_ext_d2i(xcert, NID_ext_key_usage, NULL, NULL);
585
0
  if (!oid_stack)
586
0
    return FALSE;
587
588
0
  if (sk_ASN1_OBJECT_find(oid_stack, oid) >= 0)
589
0
    ret = TRUE;
590
591
0
  sk_ASN1_OBJECT_pop_free(oid_stack, ASN1_OBJECT_free);
592
0
  return ret;
593
0
}
594
595
void x509_utils_print_info(const X509* xcert)
596
0
{
597
0
  char* fp = NULL;
598
0
  char* issuer = NULL;
599
0
  char* subject = NULL;
600
0
  subject = x509_utils_get_subject(xcert);
601
0
  issuer = x509_utils_get_issuer(xcert);
602
0
  fp = (char*)x509_utils_get_hash(xcert, "sha256", NULL);
603
604
0
  if (!fp)
605
0
  {
606
0
    WLog_ERR(TAG, "error computing fingerprint");
607
0
    goto out_free_issuer;
608
0
  }
609
610
0
  WLog_INFO(TAG, "Certificate details:");
611
0
  WLog_INFO(TAG, "\tSubject: %s", subject);
612
0
  WLog_INFO(TAG, "\tIssuer: %s", issuer);
613
0
  WLog_INFO(TAG, "\tThumbprint: %s", fp);
614
0
  WLog_INFO(TAG,
615
0
            "The above X.509 certificate could not be verified, possibly because you do not have "
616
0
            "the CA certificate in your certificate store, or the certificate has expired. "
617
0
            "Please look at the OpenSSL documentation on how to add a private CA to the store.");
618
0
  free(fp);
619
0
out_free_issuer:
620
0
  free(issuer);
621
0
  free(subject);
622
0
}
623
624
X509* x509_utils_from_pem(const char* data, size_t len, BOOL fromFile)
625
0
{
626
0
  X509* x509 = NULL;
627
0
  BIO* bio = NULL;
628
0
  if (fromFile)
629
0
    bio = BIO_new_file(data, "rb");
630
0
  else
631
0
  {
632
0
    if (len > INT_MAX)
633
0
      return NULL;
634
635
0
    bio = BIO_new_mem_buf(data, (int)len);
636
0
  }
637
638
0
  if (!bio)
639
0
  {
640
0
    WLog_ERR(TAG, "BIO_new failed for certificate");
641
0
    return NULL;
642
0
  }
643
644
0
  x509 = PEM_read_bio_X509(bio, NULL, NULL, 0);
645
0
  BIO_free_all(bio);
646
0
  if (!x509)
647
0
    WLog_ERR(TAG, "PEM_read_bio_X509 returned NULL [input length %" PRIuz "]", len);
648
649
0
  return x509;
650
0
}
651
652
static WINPR_MD_TYPE hash_nid_to_winpr(int hash_nid)
653
0
{
654
0
  switch (hash_nid)
655
0
  {
656
0
    case NID_md2:
657
0
      return WINPR_MD_MD2;
658
0
    case NID_md4:
659
0
      return WINPR_MD_MD4;
660
0
    case NID_md5:
661
0
      return WINPR_MD_MD5;
662
0
    case NID_sha1:
663
0
      return WINPR_MD_SHA1;
664
0
    case NID_sha224:
665
0
      return WINPR_MD_SHA224;
666
0
    case NID_sha256:
667
0
      return WINPR_MD_SHA256;
668
0
    case NID_sha384:
669
0
      return WINPR_MD_SHA384;
670
0
    case NID_sha512:
671
0
      return WINPR_MD_SHA512;
672
0
    case NID_ripemd160:
673
0
      return WINPR_MD_RIPEMD160;
674
0
#if (OPENSSL_VERSION_NUMBER >= 0x1010101fL) && !defined(LIBRESSL_VERSION_NUMBER)
675
0
    case NID_sha3_224:
676
0
      return WINPR_MD_SHA3_224;
677
0
    case NID_sha3_256:
678
0
      return WINPR_MD_SHA3_256;
679
0
    case NID_sha3_384:
680
0
      return WINPR_MD_SHA3_384;
681
0
    case NID_sha3_512:
682
0
      return WINPR_MD_SHA3_512;
683
0
    case NID_shake128:
684
0
      return WINPR_MD_SHAKE128;
685
0
    case NID_shake256:
686
0
      return WINPR_MD_SHAKE256;
687
0
#endif
688
0
    case NID_undef:
689
0
    default:
690
0
      return WINPR_MD_NONE;
691
0
  }
692
0
}
693
694
static WINPR_MD_TYPE get_rsa_pss_digest(const X509_ALGOR* alg)
695
0
{
696
0
  WINPR_MD_TYPE ret = WINPR_MD_NONE;
697
0
  WINPR_MD_TYPE message_digest = WINPR_MD_NONE;
698
0
  WINPR_MD_TYPE mgf1_digest = WINPR_MD_NONE;
699
0
  int param_type = 0;
700
0
  const void* param_value = NULL;
701
0
  const ASN1_STRING* sequence = NULL;
702
0
  const unsigned char* inp = NULL;
703
0
  RSA_PSS_PARAMS* params = NULL;
704
0
  X509_ALGOR* mgf1_digest_alg = NULL;
705
706
  /* The RSA-PSS digest is encoded in a complex structure, defined in
707
  https://www.rfc-editor.org/rfc/rfc4055.html. */
708
0
  X509_ALGOR_get0(NULL, &param_type, &param_value, alg);
709
710
  /* param_type and param_value the parameter in ASN1_TYPE form, but split into two parameters. A
711
  SEQUENCE is has type V_ASN1_SEQUENCE, and the value is an ASN1_STRING with the encoded
712
  structure. */
713
0
  if (param_type != V_ASN1_SEQUENCE)
714
0
    goto end;
715
0
  sequence = param_value;
716
717
  /* Decode the structure. */
718
0
  inp = ASN1_STRING_get0_data(sequence);
719
0
  params = d2i_RSA_PSS_PARAMS(NULL, &inp, ASN1_STRING_length(sequence));
720
0
  if (params == NULL)
721
0
    goto end;
722
723
  /* RSA-PSS uses two hash algorithms, a message digest and also an MGF function which is, itself,
724
  parameterized by a hash function. Both fields default to SHA-1, so we must also check for the
725
  value being NULL. */
726
0
  message_digest = WINPR_MD_SHA1;
727
0
  if (params->hashAlgorithm != NULL)
728
0
  {
729
0
    const ASN1_OBJECT* obj = NULL;
730
0
    X509_ALGOR_get0(&obj, NULL, NULL, params->hashAlgorithm);
731
0
    message_digest = hash_nid_to_winpr(OBJ_obj2nid(obj));
732
0
    if (message_digest == WINPR_MD_NONE)
733
0
      goto end;
734
0
  }
735
736
0
  mgf1_digest = WINPR_MD_SHA1;
737
0
  if (params->maskGenAlgorithm != NULL)
738
0
  {
739
0
    const ASN1_OBJECT* obj = NULL;
740
0
    int mgf_param_type = 0;
741
0
    const void* mgf_param_value = NULL;
742
0
    const ASN1_STRING* mgf_param_sequence = NULL;
743
    /* First, check this is MGF-1, the only one ever defined. */
744
0
    X509_ALGOR_get0(&obj, &mgf_param_type, &mgf_param_value, params->maskGenAlgorithm);
745
0
    if (OBJ_obj2nid(obj) != NID_mgf1)
746
0
      goto end;
747
748
    /* MGF-1 is, itself, parameterized by a hash function, encoded as an AlgorithmIdentifier. */
749
0
    if (mgf_param_type != V_ASN1_SEQUENCE)
750
0
      goto end;
751
0
    mgf_param_sequence = mgf_param_value;
752
0
    inp = ASN1_STRING_get0_data(mgf_param_sequence);
753
0
    mgf1_digest_alg = d2i_X509_ALGOR(NULL, &inp, ASN1_STRING_length(mgf_param_sequence));
754
0
    if (mgf1_digest_alg == NULL)
755
0
      goto end;
756
757
    /* Finally, extract the digest. */
758
0
    X509_ALGOR_get0(&obj, NULL, NULL, mgf1_digest_alg);
759
0
    mgf1_digest = hash_nid_to_winpr(OBJ_obj2nid(obj));
760
0
    if (mgf1_digest == WINPR_MD_NONE)
761
0
      goto end;
762
0
  }
763
764
  /* If the two digests do not match, it is ambiguous which to return. tls-server-end-point leaves
765
  it undefined, so return none.
766
  https://www.rfc-editor.org/rfc/rfc5929.html#section-4.1 */
767
0
  if (message_digest != mgf1_digest)
768
0
    goto end;
769
0
  ret = message_digest;
770
771
0
end:
772
0
  RSA_PSS_PARAMS_free(params);
773
0
  X509_ALGOR_free(mgf1_digest_alg);
774
0
  return ret;
775
0
}
776
777
WINPR_MD_TYPE x509_utils_get_signature_alg(const X509* xcert)
778
0
{
779
0
  WINPR_ASSERT(xcert);
780
781
0
  const int nid = X509_get_signature_nid(xcert);
782
783
0
  if (nid == NID_rsassaPss)
784
0
  {
785
0
    const X509_ALGOR* alg = NULL;
786
0
    X509_get0_signature(NULL, &alg, xcert);
787
0
    return get_rsa_pss_digest(alg);
788
0
  }
789
790
0
  int hash_nid = 0;
791
0
  if (OBJ_find_sigid_algs(nid, &hash_nid, NULL) != 1)
792
0
    return WINPR_MD_NONE;
793
794
0
  return hash_nid_to_winpr(hash_nid);
795
0
}
796
797
char* x509_utils_get_common_name(const X509* xcert, size_t* plength)
798
0
{
799
0
  X509_NAME* subject_name = X509_get_subject_name(xcert);
800
0
  if (subject_name == NULL)
801
0
    return NULL;
802
803
0
  const int index = X509_NAME_get_index_by_NID(subject_name, NID_commonName, -1);
804
0
  if (index < 0)
805
0
    return NULL;
806
807
0
  const X509_NAME_ENTRY* entry = X509_NAME_get_entry(subject_name, index);
808
0
  if (entry == NULL)
809
0
    return NULL;
810
811
0
  const ASN1_STRING* entry_data = X509_NAME_ENTRY_get_data(entry);
812
0
  if (entry_data == NULL)
813
0
    return NULL;
814
815
0
  BYTE* common_name_raw = NULL;
816
0
  const int length = ASN1_STRING_to_UTF8(&common_name_raw, entry_data);
817
0
  if (length < 0)
818
0
    return NULL;
819
820
0
  if (plength)
821
0
    *plength = (size_t)length;
822
823
0
  char* common_name = _strdup((char*)common_name_raw);
824
0
  OPENSSL_free(common_name_raw);
825
0
  return common_name;
826
0
}
827
828
static int verify_cb(int ok, X509_STORE_CTX* csc)
829
0
{
830
0
  if (ok != 1)
831
0
  {
832
0
    WINPR_ASSERT(csc);
833
0
    int err = X509_STORE_CTX_get_error(csc);
834
0
    int derr = X509_STORE_CTX_get_error_depth(csc);
835
0
    X509* where = X509_STORE_CTX_get_current_cert(csc);
836
0
    const char* what = X509_verify_cert_error_string(err);
837
0
    char* name = x509_utils_get_subject(where);
838
839
0
    WLog_WARN(TAG, "Certificate verification failure '%s (%d)' at stack position %d", what, err,
840
0
              derr);
841
0
    WLog_WARN(TAG, "%s", name);
842
843
0
    free(name);
844
0
  }
845
0
  return ok;
846
0
}
847
848
BOOL x509_utils_verify(X509* xcert, STACK_OF(X509) * chain, const char* certificate_store_path)
849
0
{
850
0
  const int purposes[3] = { X509_PURPOSE_SSL_SERVER, X509_PURPOSE_SSL_CLIENT, X509_PURPOSE_ANY };
851
0
  X509_STORE_CTX* csc = NULL;
852
0
  BOOL status = FALSE;
853
0
  X509_LOOKUP* lookup = NULL;
854
855
0
  if (!xcert)
856
0
    return FALSE;
857
858
0
  X509_STORE* cert_ctx = X509_STORE_new();
859
860
0
  if (cert_ctx == NULL)
861
0
    goto end;
862
863
#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
864
  OpenSSL_add_all_algorithms();
865
#else
866
0
  OPENSSL_init_crypto(OPENSSL_INIT_ADD_ALL_CIPHERS | OPENSSL_INIT_ADD_ALL_DIGESTS |
867
0
                          OPENSSL_INIT_LOAD_CONFIG,
868
0
                      NULL);
869
0
#endif
870
871
0
  if (X509_STORE_set_default_paths(cert_ctx) != 1)
872
0
    goto end;
873
874
0
  lookup = X509_STORE_add_lookup(cert_ctx, X509_LOOKUP_hash_dir());
875
876
0
  if (lookup == NULL)
877
0
    goto end;
878
879
0
  X509_LOOKUP_add_dir(lookup, NULL, X509_FILETYPE_DEFAULT);
880
881
0
  if (certificate_store_path != NULL)
882
0
  {
883
0
    X509_LOOKUP_add_dir(lookup, certificate_store_path, X509_FILETYPE_PEM);
884
0
  }
885
886
0
  X509_STORE_set_flags(cert_ctx, 0);
887
888
0
  for (size_t i = 0; i < ARRAYSIZE(purposes); i++)
889
0
  {
890
0
    int err = -1;
891
0
    int rc = -1;
892
0
    int purpose = purposes[i];
893
0
    csc = X509_STORE_CTX_new();
894
895
0
    if (csc == NULL)
896
0
      goto skip;
897
0
    if (!X509_STORE_CTX_init(csc, cert_ctx, xcert, chain))
898
0
      goto skip;
899
900
0
    X509_STORE_CTX_set_purpose(csc, purpose);
901
0
    X509_STORE_CTX_set_verify_cb(csc, verify_cb);
902
903
0
    rc = X509_verify_cert(csc);
904
0
    err = X509_STORE_CTX_get_error(csc);
905
0
  skip:
906
0
    X509_STORE_CTX_free(csc);
907
0
    if (rc == 1)
908
0
    {
909
0
      status = TRUE;
910
0
      break;
911
0
    }
912
0
    else if (err != X509_V_ERR_INVALID_PURPOSE)
913
0
      break;
914
0
  }
915
916
0
  X509_STORE_free(cert_ctx);
917
0
end:
918
0
  return status;
919
0
}