OpenVPN
ssl_verify_openssl.c
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1 /*
2  * OpenVPN -- An application to securely tunnel IP networks
3  * over a single TCP/UDP port, with support for SSL/TLS-based
4  * session authentication and key exchange,
5  * packet encryption, packet authentication, and
6  * packet compression.
7  *
8  * Copyright (C) 2002-2023 OpenVPN Inc <sales@openvpn.net>
9  * Copyright (C) 2010-2021 Fox Crypto B.V. <openvpn@foxcrypto.com>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License version 2
13  * as published by the Free Software Foundation.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License along
21  * with this program; if not, write to the Free Software Foundation, Inc.,
22  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
23  */
24 
29 #ifdef HAVE_CONFIG_H
30 #include "config.h"
31 #endif
32 
33 #include "syshead.h"
34 
35 #if defined(ENABLE_CRYPTO_OPENSSL)
36 
37 #include "ssl_verify_openssl.h"
38 
39 #include "error.h"
40 #include "ssl_openssl.h"
41 #include "ssl_verify.h"
42 #include "ssl_verify_backend.h"
43 #include "openssl_compat.h"
44 
45 #include <openssl/bn.h>
46 #include <openssl/err.h>
47 #include <openssl/x509v3.h>
48 
49 int
50 verify_callback(int preverify_ok, X509_STORE_CTX *ctx)
51 {
52  int ret = 0;
53  struct tls_session *session;
54  SSL *ssl;
55  struct gc_arena gc = gc_new();
56 
57  /* get the tls_session pointer */
58  ssl = X509_STORE_CTX_get_ex_data(ctx, SSL_get_ex_data_X509_STORE_CTX_idx());
59  ASSERT(ssl);
60  session = (struct tls_session *) SSL_get_ex_data(ssl, mydata_index);
61  ASSERT(session);
62 
63  X509 *current_cert = X509_STORE_CTX_get_current_cert(ctx);
64  struct buffer cert_hash = x509_get_sha256_fingerprint(current_cert, &gc);
65  cert_hash_remember(session, X509_STORE_CTX_get_error_depth(ctx), &cert_hash);
66 
67  /* did peer present cert which was signed by our root cert? */
68  if (!preverify_ok && !session->opt->verify_hash_no_ca)
69  {
70  /* get the X509 name */
71  char *subject = x509_get_subject(current_cert, &gc);
72  char *serial = backend_x509_get_serial(current_cert, &gc);
73 
74  if (!subject)
75  {
76  subject = "(Failed to retrieve certificate subject)";
77  }
78 
79  /* Log and ignore missing CRL errors */
80  if (X509_STORE_CTX_get_error(ctx) == X509_V_ERR_UNABLE_TO_GET_CRL)
81  {
82  msg(D_TLS_DEBUG_LOW, "VERIFY WARNING: depth=%d, %s: %s",
83  X509_STORE_CTX_get_error_depth(ctx),
84  X509_verify_cert_error_string(X509_STORE_CTX_get_error(ctx)),
85  subject);
86  ret = 1;
87  goto cleanup;
88  }
89 
90  /* Remote site specified a certificate, but it's not correct */
91  msg(D_TLS_ERRORS, "VERIFY ERROR: depth=%d, error=%s: %s, serial=%s",
92  X509_STORE_CTX_get_error_depth(ctx),
93  X509_verify_cert_error_string(X509_STORE_CTX_get_error(ctx)),
94  subject, serial ? serial : "<not available>");
95 
96  ERR_clear_error();
97 
98  session->verified = false;
99  goto cleanup;
100  }
101 
102  if (SUCCESS != verify_cert(session, current_cert, X509_STORE_CTX_get_error_depth(ctx)))
103  {
104  goto cleanup;
105  }
106 
107  ret = 1;
108 
109 cleanup:
110  gc_free(&gc);
111 
112  return ret;
113 }
114 
115 #ifdef ENABLE_X509ALTUSERNAME
116 bool
117 x509_username_field_ext_supported(const char *fieldname)
118 {
119  int nid = OBJ_txt2nid(fieldname);
120  return nid == NID_subject_alt_name || nid == NID_issuer_alt_name;
121 }
122 
123 static
124 bool
125 extract_x509_extension(X509 *cert, char *fieldname, char *out, int size)
126 {
127  bool retval = false;
128  char *buf = 0;
129 
130  if (!x509_username_field_ext_supported(fieldname))
131  {
133  "ERROR: --x509-username-field 'ext:%s' not supported", fieldname);
134  return false;
135  }
136 
137  int nid = OBJ_txt2nid(fieldname);
138  GENERAL_NAMES *extensions = X509_get_ext_d2i(cert, nid, NULL, NULL);
139  if (extensions)
140  {
141  int numalts;
142  int i;
143  /* get amount of alternatives,
144  * RFC2459 claims there MUST be at least
145  * one, but we don't depend on it...
146  */
147 
148  numalts = sk_GENERAL_NAME_num(extensions);
149 
150  /* loop through all alternatives */
151  for (i = 0; i<numalts; i++)
152  {
153  /* get a handle to alternative name number i */
154  const GENERAL_NAME *name = sk_GENERAL_NAME_value(extensions, i );
155 
156  switch (name->type)
157  {
158  case GEN_EMAIL:
159  if (ASN1_STRING_to_UTF8((unsigned char **)&buf, name->d.ia5) < 0)
160  {
161  continue;
162  }
163  if (strlen(buf) != name->d.ia5->length)
164  {
165  msg(D_TLS_ERRORS, "ASN1 ERROR: string contained terminating zero");
166  OPENSSL_free(buf);
167  }
168  else
169  {
170  strncpynt(out, buf, size);
171  OPENSSL_free(buf);
172  retval = true;
173  }
174  break;
175 
176  default:
177  msg(D_TLS_DEBUG, "%s: ignoring general name field type %i",
178  __func__, name->type);
179  break;
180  }
181  }
182  GENERAL_NAMES_free(extensions);
183  }
184  return retval;
185 }
186 #endif /* ENABLE_X509ALTUSERNAME */
187 
188 /*
189  * Extract a field from an X509 subject name.
190  *
191  * Example:
192  *
193  * /C=US/ST=CO/L=Denver/O=ORG/CN=First-CN/CN=Test-CA/Email=jim@yonan.net
194  *
195  * The common name is 'Test-CA'
196  *
197  * Return true on success, false on error (insufficient buffer size in 'out'
198  * to contain result is grounds for error).
199  */
200 static result_t
201 extract_x509_field_ssl(X509_NAME *x509, const char *field_name, char *out,
202  int size)
203 {
204  int lastpos = -1;
205  int tmp = -1;
206  X509_NAME_ENTRY *x509ne = NULL;
207  ASN1_STRING *asn1 = NULL;
208  unsigned char *buf = NULL;
209  ASN1_OBJECT *field_name_obj = OBJ_txt2obj(field_name, 0);
210 
211  if (field_name_obj == NULL)
212  {
213  msg(D_TLS_ERRORS, "Invalid X509 attribute name '%s'", field_name);
214  return FAILURE;
215  }
216 
217  ASSERT(size > 0);
218  *out = '\0';
219  do
220  {
221  lastpos = tmp;
222  tmp = X509_NAME_get_index_by_OBJ(x509, field_name_obj, lastpos);
223  } while (tmp > -1);
224 
225  ASN1_OBJECT_free(field_name_obj);
226 
227  /* Nothing found */
228  if (lastpos == -1)
229  {
230  return FAILURE;
231  }
232 
233  x509ne = X509_NAME_get_entry(x509, lastpos);
234  if (!x509ne)
235  {
236  return FAILURE;
237  }
238 
239  asn1 = X509_NAME_ENTRY_get_data(x509ne);
240  if (!asn1)
241  {
242  return FAILURE;
243  }
244  if (ASN1_STRING_to_UTF8(&buf, asn1) < 0)
245  {
246  return FAILURE;
247  }
248 
249  strncpynt(out, (char *)buf, size);
250 
251  {
252  const result_t ret = (strlen((char *)buf) < size) ? SUCCESS : FAILURE;
253  OPENSSL_free(buf);
254  return ret;
255  }
256 }
257 
258 result_t
259 backend_x509_get_username(char *common_name, int cn_len,
260  char *x509_username_field, X509 *peer_cert)
261 {
262 #ifdef ENABLE_X509ALTUSERNAME
263  if (strncmp("ext:", x509_username_field, 4) == 0)
264  {
265  if (!extract_x509_extension(peer_cert, x509_username_field+4, common_name, cn_len))
266  {
267  return FAILURE;
268  }
269  }
270  else if (strcmp(LN_serialNumber, x509_username_field) == 0)
271  {
272  ASN1_INTEGER *asn1_i = X509_get_serialNumber(peer_cert);
273  struct gc_arena gc = gc_new();
274  char *serial = format_hex_ex(asn1_i->data, asn1_i->length,
275  0, 1 | FHE_CAPS, NULL, &gc);
276 
277  if (!serial || cn_len <= strlen(serial)+2)
278  {
279  gc_free(&gc);
280  return FAILURE;
281  }
282  openvpn_snprintf(common_name, cn_len, "0x%s", serial);
283  gc_free(&gc);
284  }
285  else
286 #endif /* ifdef ENABLE_X509ALTUSERNAME */
287  if (FAILURE == extract_x509_field_ssl(X509_get_subject_name(peer_cert),
288  x509_username_field, common_name, cn_len))
289  {
290  return FAILURE;
291  }
292 
293  return SUCCESS;
294 }
295 
296 char *
298 {
299  ASN1_INTEGER *asn1_i;
300  BIGNUM *bignum;
301  char *openssl_serial, *serial;
302 
303  asn1_i = X509_get_serialNumber(cert);
304  bignum = ASN1_INTEGER_to_BN(asn1_i, NULL);
305  openssl_serial = BN_bn2dec(bignum);
306 
307  serial = string_alloc(openssl_serial, gc);
308 
309  BN_free(bignum);
310  OPENSSL_free(openssl_serial);
311 
312  return serial;
313 }
314 
315 char *
317 {
318  const ASN1_INTEGER *asn1_i = X509_get_serialNumber(cert);
319 
320  return format_hex_ex(asn1_i->data, asn1_i->length, 0, 1, ":", gc);
321 }
322 
323 struct buffer
324 x509_get_sha1_fingerprint(X509 *cert, struct gc_arena *gc)
325 {
326  const EVP_MD *sha1 = EVP_sha1();
327  struct buffer hash = alloc_buf_gc(EVP_MD_size(sha1), gc);
328  X509_digest(cert, EVP_sha1(), BPTR(&hash), NULL);
329  ASSERT(buf_inc_len(&hash, EVP_MD_size(sha1)));
330  return hash;
331 }
332 
333 struct buffer
334 x509_get_sha256_fingerprint(X509 *cert, struct gc_arena *gc)
335 {
336  const EVP_MD *sha256 = EVP_sha256();
337  struct buffer hash = alloc_buf_gc(EVP_MD_size(sha256), gc);
338  X509_digest(cert, EVP_sha256(), BPTR(&hash), NULL);
339  ASSERT(buf_inc_len(&hash, EVP_MD_size(sha256)));
340  return hash;
341 }
342 
343 char *
344 x509_get_subject(X509 *cert, struct gc_arena *gc)
345 {
346  BIO *subject_bio = NULL;
347  BUF_MEM *subject_mem;
348  char *subject = NULL;
349 
350  subject_bio = BIO_new(BIO_s_mem());
351  if (subject_bio == NULL)
352  {
353  goto err;
354  }
355 
356  X509_NAME_print_ex(subject_bio, X509_get_subject_name(cert),
357  0, XN_FLAG_SEP_CPLUS_SPC | XN_FLAG_FN_SN
358  |ASN1_STRFLGS_UTF8_CONVERT | ASN1_STRFLGS_ESC_CTRL);
359 
360  if (BIO_eof(subject_bio))
361  {
362  goto err;
363  }
364 
365  BIO_get_mem_ptr(subject_bio, &subject_mem);
366 
367  subject = gc_malloc(subject_mem->length + 1, false, gc);
368 
369  memcpy(subject, subject_mem->data, subject_mem->length);
370  subject[subject_mem->length] = '\0';
371 
372 err:
373  BIO_free(subject_bio);
374  return subject;
375 }
376 
377 
378 /*
379  * x509-track implementation -- save X509 fields to environment,
380  * using the naming convention:
381  *
382  * X509_{cert_depth}_{name}={value}
383  *
384  * This function differs from x509_setenv below in the following ways:
385  *
386  * (1) Only explicitly named attributes in xt are saved, per usage
387  * of "x509-track" program options.
388  * (2) Only the level 0 cert info is saved unless the XT_FULL_CHAIN
389  * flag is set in xt->flags (corresponds with prepending a '+'
390  * to the name when specified by "x509-track" program option).
391  * (3) This function supports both X509 subject name fields as
392  * well as X509 V3 extensions.
393  * (4) This function can return the SHA1 fingerprint of a cert, e.g.
394  * x509-track "+SHA1"
395  * will return the SHA1 fingerprint for each certificate in the
396  * peer chain.
397  */
398 
399 void
400 x509_track_add(const struct x509_track **ll_head, const char *name, int msglevel, struct gc_arena *gc)
401 {
402  struct x509_track *xt;
403  ALLOC_OBJ_CLEAR_GC(xt, struct x509_track, gc);
404  if (*name == '+')
405  {
406  xt->flags |= XT_FULL_CHAIN;
407  ++name;
408  }
409  xt->name = name;
410  xt->nid = OBJ_txt2nid(name);
411  if (xt->nid != NID_undef)
412  {
413  xt->next = *ll_head;
414  *ll_head = xt;
415  }
416  else
417  {
418  msg(msglevel, "x509_track: no such attribute '%s'", name);
419  }
420 }
421 
422 /* worker method for setenv_x509_track */
423 static void
424 do_setenv_x509(struct env_set *es, const char *name, char *value, int depth)
425 {
426  char *name_expand;
427  size_t name_expand_size;
428 
429  string_mod(value, CC_ANY, CC_CRLF, '?');
430  msg(D_X509_ATTR, "X509 ATTRIBUTE name='%s' value='%s' depth=%d", name, value, depth);
431  name_expand_size = 64 + strlen(name);
432  name_expand = (char *) malloc(name_expand_size);
433  check_malloc_return(name_expand);
434  openvpn_snprintf(name_expand, name_expand_size, "X509_%d_%s", depth, name);
435  setenv_str(es, name_expand, value);
436  free(name_expand);
437 }
438 
439 void
440 x509_setenv_track(const struct x509_track *xt, struct env_set *es, const int depth, X509 *x509)
441 {
442  struct gc_arena gc = gc_new();
443  X509_NAME *x509_name = X509_get_subject_name(x509);
444  const char nullc = '\0';
445 
446  while (xt)
447  {
448  if (depth == 0 || (xt->flags & XT_FULL_CHAIN))
449  {
450  switch (xt->nid)
451  {
452  case NID_sha1:
453  case NID_sha256:
454  {
455  struct buffer fp_buf;
456  char *fp_str = NULL;
457 
458  if (xt->nid == NID_sha1)
459  {
460  fp_buf = x509_get_sha1_fingerprint(x509, &gc);
461  }
462  else
463  {
464  fp_buf = x509_get_sha256_fingerprint(x509, &gc);
465  }
466 
467  fp_str = format_hex_ex(BPTR(&fp_buf), BLEN(&fp_buf), 0,
468  1 | FHE_CAPS, ":", &gc);
469  do_setenv_x509(es, xt->name, fp_str, depth);
470  }
471  break;
472 
473  default:
474  {
475  int i = X509_NAME_get_index_by_NID(x509_name, xt->nid, -1);
476  if (i >= 0)
477  {
478  X509_NAME_ENTRY *ent = X509_NAME_get_entry(x509_name, i);
479  if (ent)
480  {
481  ASN1_STRING *val = X509_NAME_ENTRY_get_data(ent);
482  unsigned char *buf = NULL;
483  if (ASN1_STRING_to_UTF8(&buf, val) >= 0)
484  {
485  do_setenv_x509(es, xt->name, (char *)buf, depth);
486  OPENSSL_free(buf);
487  }
488  }
489  }
490  else
491  {
492  i = X509_get_ext_by_NID(x509, xt->nid, -1);
493  if (i >= 0)
494  {
495  X509_EXTENSION *ext = X509_get_ext(x509, i);
496  if (ext)
497  {
498  BIO *bio = BIO_new(BIO_s_mem());
499  if (bio)
500  {
501  if (X509V3_EXT_print(bio, ext, 0, 0))
502  {
503  if (BIO_write(bio, &nullc, 1) == 1)
504  {
505  char *str;
506  BIO_get_mem_data(bio, &str);
507  do_setenv_x509(es, xt->name, str, depth);
508  }
509  }
510  BIO_free(bio);
511  }
512  }
513  }
514  }
515  }
516  }
517  }
518  xt = xt->next;
519  }
520  gc_free(&gc);
521 }
522 
523 /*
524  * Save X509 fields to environment, using the naming convention:
525  *
526  * X509_{cert_depth}_{name}={value}
527  */
528 void
529 x509_setenv(struct env_set *es, int cert_depth, openvpn_x509_cert_t *peer_cert)
530 {
531  int i, n;
532  int fn_nid;
533  ASN1_OBJECT *fn;
534  ASN1_STRING *val;
535  X509_NAME_ENTRY *ent;
536  const char *objbuf;
537  unsigned char *buf = NULL;
538  char *name_expand;
539  size_t name_expand_size;
540  X509_NAME *x509 = X509_get_subject_name(peer_cert);
541 
542  n = X509_NAME_entry_count(x509);
543  for (i = 0; i < n; ++i)
544  {
545  ent = X509_NAME_get_entry(x509, i);
546  if (!ent)
547  {
548  continue;
549  }
550  fn = X509_NAME_ENTRY_get_object(ent);
551  if (!fn)
552  {
553  continue;
554  }
555  val = X509_NAME_ENTRY_get_data(ent);
556  if (!val)
557  {
558  continue;
559  }
560  fn_nid = OBJ_obj2nid(fn);
561  if (fn_nid == NID_undef)
562  {
563  continue;
564  }
565  objbuf = OBJ_nid2sn(fn_nid);
566  if (!objbuf)
567  {
568  continue;
569  }
570  if (ASN1_STRING_to_UTF8(&buf, val) < 0)
571  {
572  continue;
573  }
574  name_expand_size = 64 + strlen(objbuf);
575  name_expand = (char *) malloc(name_expand_size);
576  check_malloc_return(name_expand);
577  openvpn_snprintf(name_expand, name_expand_size, "X509_%d_%s", cert_depth,
578  objbuf);
579  string_mod(name_expand, CC_PRINT, CC_CRLF, '_');
580  string_mod((char *)buf, CC_PRINT, CC_CRLF, '_');
581  setenv_str_incr(es, name_expand, (char *)buf);
582  free(name_expand);
583  OPENSSL_free(buf);
584  }
585 }
586 
587 result_t
589 {
590  if (usage == NS_CERT_CHECK_NONE)
591  {
592  return SUCCESS;
593  }
595  {
596  /*
597  * Unfortunately, X509_check_purpose() does some weird thing that
598  * prevent it to take a const argument
599  */
600  result_t result = X509_check_purpose(peer_cert, X509_PURPOSE_SSL_CLIENT, 0) ?
601  SUCCESS : FAILURE;
602 
603  /*
604  * old versions of OpenSSL allow us to make the less strict check we used to
605  * do. If this less strict check pass, warn user that this might not be the
606  * case when its distribution will update to OpenSSL 1.1
607  */
608  if (result == FAILURE)
609  {
610  ASN1_BIT_STRING *ns;
611  ns = X509_get_ext_d2i(peer_cert, NID_netscape_cert_type, NULL, NULL);
612  result = (ns && ns->length > 0 && (ns->data[0] & NS_SSL_CLIENT)) ? SUCCESS : FAILURE;
613  if (result == SUCCESS)
614  {
615  msg(M_WARN, "X509: Certificate is a client certificate yet it's purpose "
616  "cannot be verified (check may fail in the future)");
617  }
618  ASN1_BIT_STRING_free(ns);
619  }
620  return result;
621  }
623  {
624  /*
625  * Unfortunately, X509_check_purpose() does some weird thing that
626  * prevent it to take a const argument
627  */
628  result_t result = X509_check_purpose(peer_cert, X509_PURPOSE_SSL_SERVER, 0) ?
629  SUCCESS : FAILURE;
630 
631  /*
632  * old versions of OpenSSL allow us to make the less strict check we used to
633  * do. If this less strict check pass, warn user that this might not be the
634  * case when its distribution will update to OpenSSL 1.1
635  */
636  if (result == FAILURE)
637  {
638  ASN1_BIT_STRING *ns;
639  ns = X509_get_ext_d2i(peer_cert, NID_netscape_cert_type, NULL, NULL);
640  result = (ns && ns->length > 0 && (ns->data[0] & NS_SSL_SERVER)) ? SUCCESS : FAILURE;
641  if (result == SUCCESS)
642  {
643  msg(M_WARN, "X509: Certificate is a server certificate yet it's purpose "
644  "cannot be verified (check may fail in the future)");
645  }
646  ASN1_BIT_STRING_free(ns);
647  }
648  return result;
649  }
650 
651  return FAILURE;
652 }
653 
654 result_t
655 x509_verify_cert_ku(X509 *x509, const unsigned *const expected_ku,
656  int expected_len)
657 {
658  ASN1_BIT_STRING *ku = X509_get_ext_d2i(x509, NID_key_usage, NULL, NULL);
659 
660  if (ku == NULL)
661  {
662  msg(D_TLS_ERRORS, "Certificate does not have key usage extension");
663  return FAILURE;
664  }
665 
666  if (expected_ku[0] == OPENVPN_KU_REQUIRED)
667  {
668  /* Extension required, value checked by TLS library */
669  ASN1_BIT_STRING_free(ku);
670  return SUCCESS;
671  }
672 
673  unsigned nku = 0;
674  for (size_t i = 0; i < 8; i++)
675  {
676  if (ASN1_BIT_STRING_get_bit(ku, i))
677  {
678  nku |= 1 << (7 - i);
679  }
680  }
681 
682  /*
683  * Fixup if no LSB bits
684  */
685  if ((nku & 0xff) == 0)
686  {
687  nku >>= 8;
688  }
689 
690  msg(D_HANDSHAKE, "Validating certificate key usage");
691  result_t fFound = FAILURE;
692  for (size_t i = 0; fFound != SUCCESS && i < expected_len; i++)
693  {
694  if (expected_ku[i] != 0 && (nku & expected_ku[i]) == expected_ku[i])
695  {
696  fFound = SUCCESS;
697  }
698  }
699 
700  if (fFound != SUCCESS)
701  {
703  "ERROR: Certificate has key usage %04x, expected one of:", nku);
704  for (size_t i = 0; i < expected_len && expected_ku[i]; i++)
705  {
706  msg(D_TLS_ERRORS, " * %04x", expected_ku[i]);
707  }
708  }
709 
710  ASN1_BIT_STRING_free(ku);
711 
712  return fFound;
713 }
714 
715 result_t
716 x509_verify_cert_eku(X509 *x509, const char *const expected_oid)
717 {
718  EXTENDED_KEY_USAGE *eku = NULL;
719  result_t fFound = FAILURE;
720 
721  if ((eku = (EXTENDED_KEY_USAGE *) X509_get_ext_d2i(x509, NID_ext_key_usage,
722  NULL, NULL)) == NULL)
723  {
724  msg(D_HANDSHAKE, "Certificate does not have extended key usage extension");
725  }
726  else
727  {
728  int i;
729 
730  msg(D_HANDSHAKE, "Validating certificate extended key usage");
731  for (i = 0; SUCCESS != fFound && i < sk_ASN1_OBJECT_num(eku); i++)
732  {
733  ASN1_OBJECT *oid = sk_ASN1_OBJECT_value(eku, i);
734  char szOid[1024];
735 
736  if (SUCCESS != fFound && OBJ_obj2txt(szOid, sizeof(szOid), oid, 0) != -1)
737  {
738  msg(D_HANDSHAKE, "++ Certificate has EKU (str) %s, expects %s",
739  szOid, expected_oid);
740  if (!strcmp(expected_oid, szOid))
741  {
742  fFound = SUCCESS;
743  }
744  }
745  if (SUCCESS != fFound && OBJ_obj2txt(szOid, sizeof(szOid), oid, 1) != -1)
746  {
747  msg(D_HANDSHAKE, "++ Certificate has EKU (oid) %s, expects %s",
748  szOid, expected_oid);
749  if (!strcmp(expected_oid, szOid))
750  {
751  fFound = SUCCESS;
752  }
753  }
754  }
755  }
756 
757  if (eku != NULL)
758  {
759  sk_ASN1_OBJECT_pop_free(eku, ASN1_OBJECT_free);
760  }
761 
762  return fFound;
763 }
764 
765 result_t
766 x509_write_pem(FILE *peercert_file, X509 *peercert)
767 {
768  if (PEM_write_X509(peercert_file, peercert) < 0)
769  {
770  msg(M_NONFATAL, "Failed to write peer certificate in PEM format");
771  return FAILURE;
772  }
773  return SUCCESS;
774 }
775 
776 bool
778 {
779  if (!opt->crl_file || (opt->ssl_flags & SSLF_CRL_VERIFY_DIR))
780  {
781  return false;
782  }
783 
784  X509_STORE *store = SSL_CTX_get_cert_store(opt->ssl_ctx.ctx);
785  if (!store)
786  {
787  crypto_msg(M_FATAL, "Cannot get certificate store");
788  }
789 
790  STACK_OF(X509_OBJECT) *objs = X509_STORE_get0_objects(store);
791  for (int i = 0; i < sk_X509_OBJECT_num(objs); i++)
792  {
793  X509_OBJECT *obj = sk_X509_OBJECT_value(objs, i);
794  ASSERT(obj);
795  if (X509_OBJECT_get_type(obj) == X509_LU_CRL)
796  {
797  return false;
798  }
799  }
800  return true;
801 }
802 
803 #endif /* defined(ENABLE_CRYPTO_OPENSSL) */
D_TLS_DEBUG
#define D_TLS_DEBUG
Definition: errlevel.h:165
error.h
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static struct gc_arena gc_new(void)
Definition: buffer.h:1011
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#define M_FATAL
Definition: error.h:95
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int mydata_index
Allocate space in SSL objects in which to store a struct tls_session pointer back to parent.
Definition: ssl_openssl.c:81
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#define M_NONFATAL
Definition: error.h:96
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struct env_set * es
Definition: test_pkcs11.c:131
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Definition: list.h:58
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#define D_TLS_DEBUG_LOW
Definition: errlevel.h:77
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result_t verify_cert(struct tls_session *session, openvpn_x509_cert_t *cert, int cert_depth)
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#define D_HANDSHAKE
Definition: errlevel.h:72
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struct buffer alloc_buf_gc(size_t size, struct gc_arena *gc)
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void x509_setenv(struct env_set *es, int cert_depth, openvpn_x509_cert_t *peer_cert)
Definition: ssl_verify_openssl.c:529
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Result of verification function.
Definition: ssl_verify_backend.h:35
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#define ASSERT(x)
Definition: error.h:201
STACK_OF
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Fetch the X509 object stack from the X509 store.
Definition: openssl_compat.h:216
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result_t x509_verify_cert_eku(X509 *x509, const char *const expected_oid)
Definition: ssl_verify_openssl.c:716
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static bool buf_inc_len(struct buffer *buf, int inc)
Definition: buffer.h:608
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Definition: ssl_common.h:293
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result_t x509_write_pem(FILE *peercert_file, X509 *peercert)
Definition: ssl_verify_openssl.c:766
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#define BLEN(buf)
Definition: buffer.h:127
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#define CC_PRINT
Definition: buffer.h:911
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int nid
Definition: ssl_verify.h:220
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#define SSLF_CRL_VERIFY_DIR
Definition: ssl_common.h:409
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unsigned int ssl_flags
Definition: ssl_common.h:415
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#define M_WARN
Definition: error.h:97
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result_t x509_verify_cert_ku(X509 *x509, const unsigned *const expected_ku, int expected_len)
Definition: ssl_verify_openssl.c:655
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#define ALLOC_OBJ_CLEAR_GC(dptr, type, gc)
Definition: buffer.h:1083
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#define FHE_CAPS
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Definition: ssl_verify.h:217
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Wrapper structure for dynamically allocated memory.
Definition: buffer.h:60
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Store the supplied name value pair in the env_set.
Definition: env_set.c:305
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char * backend_x509_get_serial_hex(openvpn_x509_cert_t *cert, struct gc_arena *gc)
Definition: ssl_verify_openssl.c:316
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@ SUCCESS
Definition: ssl_verify_backend.h:35
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Definition: errlevel.h:59
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static int X509_OBJECT_get_type(const X509_OBJECT *obj)
Get the type of an X509 object.
Definition: openssl_compat.h:229
openssl_compat.h
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const struct x509_track * next
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CC_ANY
#define CC_ANY
Definition: buffer.h:903
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Security parameter state of a single session within a VPN tunnel.
Definition: ssl_common.h:468
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Definition: ssl_verify.h:218
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#define BPTR(buf)
Definition: buffer.h:124
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Garbage collection arena used to keep track of dynamically allocated memory.
Definition: buffer.h:116
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Definition: env_set.c:283
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static void strncpynt(char *dest, const char *src, size_t maxlen)
Definition: buffer.h:361
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Definition: env_set.h:42
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X509 openvpn_x509_cert_t
Definition: openvpn-plugin.h:40
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result_t x509_verify_ns_cert_type(openvpn_x509_cert_t *peer_cert, const int usage)
Definition: ssl_verify_openssl.c:588
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Definition: options.c:4769
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Retrieve the certificate's SHA256 fingerprint.
Definition: ssl_verify_openssl.c:334
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#define crypto_msg(flags,...)
Retrieve any OpenSSL errors, then print the supplied error message.
Definition: crypto_openssl.h:115
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Definition: ssl_common.h:340
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Definition: ssl_verify_openssl.c:424
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OPENVPN_KU_REQUIRED
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Require keyUsage to be present in cert (0xFFFF is an invalid KU value)
Definition: ssl_verify.h:234
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Definition: ssl_verify_openssl.c:324
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Definition: ssl_verify_openssl.c:201
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Return true iff a CRL is configured, but is not loaded.
Definition: ssl_verify_openssl.c:777
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#define D_X509_ATTR
Definition: errlevel.h:103
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Definition: error.h:150
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Verify that the remote OpenVPN peer's certificate allows setting up a VPN tunnel.
Definition: ssl_verify_openssl.c:50
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Definition: ssl_verify.h:214
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Do not perform Netscape certificate type verification.
Definition: ssl_verify.h:229
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#define NS_CERT_CHECK_NONE
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Definition: ssl_verify.h:227
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Definition: ssl_verify.h:231
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FAILURE
@ FAILURE
Definition: ssl_verify_backend.h:35
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static int cleanup(void **state)
Definition: test_pkcs11.c:278