1 /*
2 * X.509 certificate parsing and verification
3 *
4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
5 * SPDX-License-Identifier: GPL-2.0
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License along
18 * with this program; if not, write to the Free Software Foundation, Inc.,
19 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * This file is part of mbed TLS (https://tls.mbed.org)
22 */
23 /*
24 * The ITU-T X.509 standard defines a certificate format for PKI.
25 *
26 * http://www.ietf.org/rfc/rfc5280.txt (Certificates and CRLs)
27 * http://www.ietf.org/rfc/rfc3279.txt (Alg IDs for CRLs)
28 * http://www.ietf.org/rfc/rfc2986.txt (CSRs, aka PKCS#10)
29 *
30 * http://www.itu.int/ITU-T/studygroups/com17/languages/X.680-0207.pdf
31 * http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf
32 *
33 * [SIRO] https://cabforum.org/wp-content/uploads/Chunghwatelecom201503cabforumV4.pdf
34 */
35
36 #if !defined(MBEDTLS_CONFIG_FILE)
37 #include "mbedtls/config.h"
38 #else
39 #include MBEDTLS_CONFIG_FILE
40 #endif
41
42 #if defined(MBEDTLS_X509_CRT_PARSE_C)
43
44 #include "mbedtls/x509_crt.h"
45 #include "mbedtls/oid.h"
46 #include "mbedtls/platform_util.h"
47
48 #include <string.h>
49
50 #if defined(MBEDTLS_PEM_PARSE_C)
51 #include "mbedtls/pem.h"
52 #endif
53
54 #if defined(MBEDTLS_PLATFORM_C)
55 #include "mbedtls/platform.h"
56 #else
57 #include <stdio.h>
58 #include <stdlib.h>
59 #define mbedtls_free free
60 #define mbedtls_calloc calloc
61 #define mbedtls_snprintf snprintf
62 #endif
63
64 #if defined(MBEDTLS_THREADING_C)
65 #include "mbedtls/threading.h"
66 #endif
67
68 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
69 #include <windows.h>
70 #else
71 #include <time.h>
72 #endif
73
74 #if defined(MBEDTLS_FS_IO)
75 #include <stdio.h>
76 #if !defined(_WIN32) || defined(EFIX64) || defined(EFI32)
77 #include <sys/types.h>
78 #include <sys/stat.h>
79 #include <dirent.h>
80 #endif /* !_WIN32 || EFIX64 || EFI32 */
81 #endif
82
83 /*
84 * Item in a verification chain: cert and flags for it
85 */
86 typedef struct {
87 mbedtls_x509_crt *crt;
88 uint32_t flags;
89 } x509_crt_verify_chain_item;
90
91 /*
92 * Max size of verification chain: end-entity + intermediates + trusted root
93 */
94 #define X509_MAX_VERIFY_CHAIN_SIZE ( MBEDTLS_X509_MAX_INTERMEDIATE_CA + 2 )
95
96 /*
97 * Default profile
98 */
99 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_default =
100 {
101 #if defined(MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_CERTIFICATES)
102 /* Allow SHA-1 (weak, but still safe in controlled environments) */
103 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA1 ) |
104 #endif
105 /* Only SHA-2 hashes */
106 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA224 ) |
107 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
108 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ) |
109 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA512 ),
110 0xFFFFFFF, /* Any PK alg */
111 0xFFFFFFF, /* Any curve */
112 2048,
113 };
114
115 /*
116 * Next-default profile
117 */
118 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_next =
119 {
120 /* Hashes from SHA-256 and above */
121 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
122 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ) |
123 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA512 ),
124 0xFFFFFFF, /* Any PK alg */
125 #if defined(MBEDTLS_ECP_C)
126 /* Curves at or above 128-bit security level */
127 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256R1 ) |
128 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP384R1 ) |
129 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP521R1 ) |
130 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP256R1 ) |
131 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP384R1 ) |
132 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP512R1 ) |
133 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256K1 ),
134 #else
135 0,
136 #endif
137 2048,
138 };
139
140 /*
141 * NSA Suite B Profile
142 */
143 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_suiteb =
144 {
145 /* Only SHA-256 and 384 */
146 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
147 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ),
148 /* Only ECDSA */
149 MBEDTLS_X509_ID_FLAG( MBEDTLS_PK_ECDSA ) |
150 MBEDTLS_X509_ID_FLAG( MBEDTLS_PK_ECKEY ),
151 #if defined(MBEDTLS_ECP_C)
152 /* Only NIST P-256 and P-384 */
153 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256R1 ) |
154 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP384R1 ),
155 #else
156 0,
157 #endif
158 0,
159 };
160
161 /*
162 * Check md_alg against profile
163 * Return 0 if md_alg is acceptable for this profile, -1 otherwise
164 */
x509_profile_check_md_alg(const mbedtls_x509_crt_profile * profile,mbedtls_md_type_t md_alg)165 static int x509_profile_check_md_alg( const mbedtls_x509_crt_profile *profile,
166 mbedtls_md_type_t md_alg )
167 {
168 if( md_alg == MBEDTLS_MD_NONE )
169 return( -1 );
170
171 if( ( profile->allowed_mds & MBEDTLS_X509_ID_FLAG( md_alg ) ) != 0 )
172 return( 0 );
173
174 return( -1 );
175 }
176
177 /*
178 * Check pk_alg against profile
179 * Return 0 if pk_alg is acceptable for this profile, -1 otherwise
180 */
x509_profile_check_pk_alg(const mbedtls_x509_crt_profile * profile,mbedtls_pk_type_t pk_alg)181 static int x509_profile_check_pk_alg( const mbedtls_x509_crt_profile *profile,
182 mbedtls_pk_type_t pk_alg )
183 {
184 if( pk_alg == MBEDTLS_PK_NONE )
185 return( -1 );
186
187 if( ( profile->allowed_pks & MBEDTLS_X509_ID_FLAG( pk_alg ) ) != 0 )
188 return( 0 );
189
190 return( -1 );
191 }
192
193 /*
194 * Check key against profile
195 * Return 0 if pk is acceptable for this profile, -1 otherwise
196 */
x509_profile_check_key(const mbedtls_x509_crt_profile * profile,const mbedtls_pk_context * pk)197 static int x509_profile_check_key( const mbedtls_x509_crt_profile *profile,
198 const mbedtls_pk_context *pk )
199 {
200 const mbedtls_pk_type_t pk_alg = mbedtls_pk_get_type( pk );
201
202 #if defined(MBEDTLS_RSA_C)
203 if( pk_alg == MBEDTLS_PK_RSA || pk_alg == MBEDTLS_PK_RSASSA_PSS )
204 {
205 if( mbedtls_pk_get_bitlen( pk ) >= profile->rsa_min_bitlen )
206 return( 0 );
207
208 return( -1 );
209 }
210 #endif
211
212 #if defined(MBEDTLS_ECP_C)
213 if( pk_alg == MBEDTLS_PK_ECDSA ||
214 pk_alg == MBEDTLS_PK_ECKEY ||
215 pk_alg == MBEDTLS_PK_ECKEY_DH )
216 {
217 const mbedtls_ecp_group_id gid = mbedtls_pk_ec( *pk )->grp.id;
218
219 if( gid == MBEDTLS_ECP_DP_NONE )
220 return( -1 );
221
222 if( ( profile->allowed_curves & MBEDTLS_X509_ID_FLAG( gid ) ) != 0 )
223 return( 0 );
224
225 return( -1 );
226 }
227 #endif
228
229 return( -1 );
230 }
231
232 /*
233 * Like memcmp, but case-insensitive and always returns -1 if different
234 */
x509_memcasecmp(const void * s1,const void * s2,size_t len)235 static int x509_memcasecmp( const void *s1, const void *s2, size_t len )
236 {
237 size_t i;
238 unsigned char diff;
239 const unsigned char *n1 = s1, *n2 = s2;
240
241 for( i = 0; i < len; i++ )
242 {
243 diff = n1[i] ^ n2[i];
244
245 if( diff == 0 )
246 continue;
247
248 if( diff == 32 &&
249 ( ( n1[i] >= 'a' && n1[i] <= 'z' ) ||
250 ( n1[i] >= 'A' && n1[i] <= 'Z' ) ) )
251 {
252 continue;
253 }
254
255 return( -1 );
256 }
257
258 return( 0 );
259 }
260
261 /*
262 * Return 0 if name matches wildcard, -1 otherwise
263 */
x509_check_wildcard(const char * cn,const mbedtls_x509_buf * name)264 static int x509_check_wildcard( const char *cn, const mbedtls_x509_buf *name )
265 {
266 size_t i;
267 size_t cn_idx = 0, cn_len = strlen( cn );
268
269 /* We can't have a match if there is no wildcard to match */
270 if( name->len < 3 || name->p[0] != '*' || name->p[1] != '.' )
271 return( -1 );
272
273 for( i = 0; i < cn_len; ++i )
274 {
275 if( cn[i] == '.' )
276 {
277 cn_idx = i;
278 break;
279 }
280 }
281
282 if( cn_idx == 0 )
283 return( -1 );
284
285 if( cn_len - cn_idx == name->len - 1 &&
286 x509_memcasecmp( name->p + 1, cn + cn_idx, name->len - 1 ) == 0 )
287 {
288 return( 0 );
289 }
290
291 return( -1 );
292 }
293
294 /*
295 * Compare two X.509 strings, case-insensitive, and allowing for some encoding
296 * variations (but not all).
297 *
298 * Return 0 if equal, -1 otherwise.
299 */
x509_string_cmp(const mbedtls_x509_buf * a,const mbedtls_x509_buf * b)300 static int x509_string_cmp( const mbedtls_x509_buf *a, const mbedtls_x509_buf *b )
301 {
302 if( a->tag == b->tag &&
303 a->len == b->len &&
304 memcmp( a->p, b->p, b->len ) == 0 )
305 {
306 return( 0 );
307 }
308
309 if( ( a->tag == MBEDTLS_ASN1_UTF8_STRING || a->tag == MBEDTLS_ASN1_PRINTABLE_STRING ) &&
310 ( b->tag == MBEDTLS_ASN1_UTF8_STRING || b->tag == MBEDTLS_ASN1_PRINTABLE_STRING ) &&
311 a->len == b->len &&
312 x509_memcasecmp( a->p, b->p, b->len ) == 0 )
313 {
314 return( 0 );
315 }
316
317 return( -1 );
318 }
319
320 /*
321 * Compare two X.509 Names (aka rdnSequence).
322 *
323 * See RFC 5280 section 7.1, though we don't implement the whole algorithm:
324 * we sometimes return unequal when the full algorithm would return equal,
325 * but never the other way. (In particular, we don't do Unicode normalisation
326 * or space folding.)
327 *
328 * Return 0 if equal, -1 otherwise.
329 */
x509_name_cmp(const mbedtls_x509_name * a,const mbedtls_x509_name * b)330 static int x509_name_cmp( const mbedtls_x509_name *a, const mbedtls_x509_name *b )
331 {
332 /* Avoid recursion, it might not be optimised by the compiler */
333 while( a != NULL || b != NULL )
334 {
335 if( a == NULL || b == NULL )
336 return( -1 );
337
338 /* type */
339 if( a->oid.tag != b->oid.tag ||
340 a->oid.len != b->oid.len ||
341 memcmp( a->oid.p, b->oid.p, b->oid.len ) != 0 )
342 {
343 return( -1 );
344 }
345
346 /* value */
347 if( x509_string_cmp( &a->val, &b->val ) != 0 )
348 return( -1 );
349
350 /* structure of the list of sets */
351 if( a->next_merged != b->next_merged )
352 return( -1 );
353
354 a = a->next;
355 b = b->next;
356 }
357
358 /* a == NULL == b */
359 return( 0 );
360 }
361
362 /*
363 * Reset (init or clear) a verify_chain
364 */
x509_crt_verify_chain_reset(mbedtls_x509_crt_verify_chain * ver_chain)365 static void x509_crt_verify_chain_reset(
366 mbedtls_x509_crt_verify_chain *ver_chain )
367 {
368 size_t i;
369
370 for( i = 0; i < MBEDTLS_X509_MAX_VERIFY_CHAIN_SIZE; i++ )
371 {
372 ver_chain->items[i].crt = NULL;
373 ver_chain->items[i].flags = -1;
374 }
375
376 ver_chain->len = 0;
377 }
378
379 /*
380 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
381 */
x509_get_version(unsigned char ** p,const unsigned char * end,int * ver)382 static int x509_get_version( unsigned char **p,
383 const unsigned char *end,
384 int *ver )
385 {
386 int ret;
387 size_t len;
388
389 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
390 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 0 ) ) != 0 )
391 {
392 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
393 {
394 *ver = 0;
395 return( 0 );
396 }
397
398 return( ret );
399 }
400
401 end = *p + len;
402
403 if( ( ret = mbedtls_asn1_get_int( p, end, ver ) ) != 0 )
404 return( MBEDTLS_ERR_X509_INVALID_VERSION + ret );
405
406 if( *p != end )
407 return( MBEDTLS_ERR_X509_INVALID_VERSION +
408 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
409
410 return( 0 );
411 }
412
413 /*
414 * Validity ::= SEQUENCE {
415 * notBefore Time,
416 * notAfter Time }
417 */
x509_get_dates(unsigned char ** p,const unsigned char * end,mbedtls_x509_time * from,mbedtls_x509_time * to)418 static int x509_get_dates( unsigned char **p,
419 const unsigned char *end,
420 mbedtls_x509_time *from,
421 mbedtls_x509_time *to )
422 {
423 int ret;
424 size_t len;
425
426 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
427 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
428 return( MBEDTLS_ERR_X509_INVALID_DATE + ret );
429
430 end = *p + len;
431
432 if( ( ret = mbedtls_x509_get_time( p, end, from ) ) != 0 )
433 return( ret );
434
435 if( ( ret = mbedtls_x509_get_time( p, end, to ) ) != 0 )
436 return( ret );
437
438 if( *p != end )
439 return( MBEDTLS_ERR_X509_INVALID_DATE +
440 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
441
442 return( 0 );
443 }
444
445 /*
446 * X.509 v2/v3 unique identifier (not parsed)
447 */
x509_get_uid(unsigned char ** p,const unsigned char * end,mbedtls_x509_buf * uid,int n)448 static int x509_get_uid( unsigned char **p,
449 const unsigned char *end,
450 mbedtls_x509_buf *uid, int n )
451 {
452 int ret;
453
454 if( *p == end )
455 return( 0 );
456
457 uid->tag = **p;
458
459 if( ( ret = mbedtls_asn1_get_tag( p, end, &uid->len,
460 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | n ) ) != 0 )
461 {
462 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
463 return( 0 );
464
465 return( ret );
466 }
467
468 uid->p = *p;
469 *p += uid->len;
470
471 return( 0 );
472 }
473
x509_get_basic_constraints(unsigned char ** p,const unsigned char * end,int * ca_istrue,int * max_pathlen)474 static int x509_get_basic_constraints( unsigned char **p,
475 const unsigned char *end,
476 int *ca_istrue,
477 int *max_pathlen )
478 {
479 int ret;
480 size_t len;
481
482 /*
483 * BasicConstraints ::= SEQUENCE {
484 * cA BOOLEAN DEFAULT FALSE,
485 * pathLenConstraint INTEGER (0..MAX) OPTIONAL }
486 */
487 *ca_istrue = 0; /* DEFAULT FALSE */
488 *max_pathlen = 0; /* endless */
489
490 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
491 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
492 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
493
494 if( *p == end )
495 return( 0 );
496
497 if( ( ret = mbedtls_asn1_get_bool( p, end, ca_istrue ) ) != 0 )
498 {
499 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
500 ret = mbedtls_asn1_get_int( p, end, ca_istrue );
501
502 if( ret != 0 )
503 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
504
505 if( *ca_istrue != 0 )
506 *ca_istrue = 1;
507 }
508
509 if( *p == end )
510 return( 0 );
511
512 if( ( ret = mbedtls_asn1_get_int( p, end, max_pathlen ) ) != 0 )
513 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
514
515 if( *p != end )
516 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
517 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
518
519 (*max_pathlen)++;
520
521 return( 0 );
522 }
523
x509_get_ns_cert_type(unsigned char ** p,const unsigned char * end,unsigned char * ns_cert_type)524 static int x509_get_ns_cert_type( unsigned char **p,
525 const unsigned char *end,
526 unsigned char *ns_cert_type)
527 {
528 int ret;
529 mbedtls_x509_bitstring bs = { 0, 0, NULL };
530
531 if( ( ret = mbedtls_asn1_get_bitstring( p, end, &bs ) ) != 0 )
532 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
533
534 if( bs.len != 1 )
535 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
536 MBEDTLS_ERR_ASN1_INVALID_LENGTH );
537
538 /* Get actual bitstring */
539 *ns_cert_type = *bs.p;
540 return( 0 );
541 }
542
x509_get_key_usage(unsigned char ** p,const unsigned char * end,unsigned int * key_usage)543 static int x509_get_key_usage( unsigned char **p,
544 const unsigned char *end,
545 unsigned int *key_usage)
546 {
547 int ret;
548 size_t i;
549 mbedtls_x509_bitstring bs = { 0, 0, NULL };
550
551 if( ( ret = mbedtls_asn1_get_bitstring( p, end, &bs ) ) != 0 )
552 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
553
554 if( bs.len < 1 )
555 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
556 MBEDTLS_ERR_ASN1_INVALID_LENGTH );
557
558 /* Get actual bitstring */
559 *key_usage = 0;
560 for( i = 0; i < bs.len && i < sizeof( unsigned int ); i++ )
561 {
562 *key_usage |= (unsigned int) bs.p[i] << (8*i);
563 }
564
565 return( 0 );
566 }
567
568 /*
569 * ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId
570 *
571 * KeyPurposeId ::= OBJECT IDENTIFIER
572 */
x509_get_ext_key_usage(unsigned char ** p,const unsigned char * end,mbedtls_x509_sequence * ext_key_usage)573 static int x509_get_ext_key_usage( unsigned char **p,
574 const unsigned char *end,
575 mbedtls_x509_sequence *ext_key_usage)
576 {
577 int ret;
578
579 if( ( ret = mbedtls_asn1_get_sequence_of( p, end, ext_key_usage, MBEDTLS_ASN1_OID ) ) != 0 )
580 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
581
582 /* Sequence length must be >= 1 */
583 if( ext_key_usage->buf.p == NULL )
584 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
585 MBEDTLS_ERR_ASN1_INVALID_LENGTH );
586
587 return( 0 );
588 }
589
590 /*
591 * SubjectAltName ::= GeneralNames
592 *
593 * GeneralNames ::= SEQUENCE SIZE (1..MAX) OF GeneralName
594 *
595 * GeneralName ::= CHOICE {
596 * otherName [0] OtherName,
597 * rfc822Name [1] IA5String,
598 * dNSName [2] IA5String,
599 * x400Address [3] ORAddress,
600 * directoryName [4] Name,
601 * ediPartyName [5] EDIPartyName,
602 * uniformResourceIdentifier [6] IA5String,
603 * iPAddress [7] OCTET STRING,
604 * registeredID [8] OBJECT IDENTIFIER }
605 *
606 * OtherName ::= SEQUENCE {
607 * type-id OBJECT IDENTIFIER,
608 * value [0] EXPLICIT ANY DEFINED BY type-id }
609 *
610 * EDIPartyName ::= SEQUENCE {
611 * nameAssigner [0] DirectoryString OPTIONAL,
612 * partyName [1] DirectoryString }
613 *
614 * NOTE: we only parse and use dNSName at this point.
615 */
x509_get_subject_alt_name(unsigned char ** p,const unsigned char * end,mbedtls_x509_sequence * subject_alt_name)616 static int x509_get_subject_alt_name( unsigned char **p,
617 const unsigned char *end,
618 mbedtls_x509_sequence *subject_alt_name )
619 {
620 int ret;
621 size_t len, tag_len;
622 mbedtls_asn1_buf *buf;
623 unsigned char tag;
624 mbedtls_asn1_sequence *cur = subject_alt_name;
625
626 /* Get main sequence tag */
627 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
628 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
629 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
630
631 if( *p + len != end )
632 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
633 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
634
635 while( *p < end )
636 {
637 if( ( end - *p ) < 1 )
638 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
639 MBEDTLS_ERR_ASN1_OUT_OF_DATA );
640
641 tag = **p;
642 (*p)++;
643 if( ( ret = mbedtls_asn1_get_len( p, end, &tag_len ) ) != 0 )
644 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
645
646 if( ( tag & MBEDTLS_ASN1_TAG_CLASS_MASK ) !=
647 MBEDTLS_ASN1_CONTEXT_SPECIFIC )
648 {
649 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
650 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
651 }
652
653 /* Skip everything but DNS name */
654 if( tag != ( MBEDTLS_ASN1_CONTEXT_SPECIFIC | 2 ) )
655 {
656 *p += tag_len;
657 continue;
658 }
659
660 /* Allocate and assign next pointer */
661 if( cur->buf.p != NULL )
662 {
663 if( cur->next != NULL )
664 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS );
665
666 cur->next = mbedtls_calloc( 1, sizeof( mbedtls_asn1_sequence ) );
667
668 if( cur->next == NULL )
669 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
670 MBEDTLS_ERR_ASN1_ALLOC_FAILED );
671
672 cur = cur->next;
673 }
674
675 buf = &(cur->buf);
676 buf->tag = tag;
677 buf->p = *p;
678 buf->len = tag_len;
679 *p += buf->len;
680 }
681
682 /* Set final sequence entry's next pointer to NULL */
683 cur->next = NULL;
684
685 if( *p != end )
686 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
687 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
688
689 return( 0 );
690 }
691
692 /*
693 * X.509 v3 extensions
694 *
695 */
x509_get_crt_ext(unsigned char ** p,const unsigned char * end,mbedtls_x509_crt * crt)696 static int x509_get_crt_ext( unsigned char **p,
697 const unsigned char *end,
698 mbedtls_x509_crt *crt )
699 {
700 int ret;
701 size_t len;
702 unsigned char *end_ext_data, *end_ext_octet;
703
704 if( ( ret = mbedtls_x509_get_ext( p, end, &crt->v3_ext, 3 ) ) != 0 )
705 {
706 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
707 return( 0 );
708
709 return( ret );
710 }
711
712 while( *p < end )
713 {
714 /*
715 * Extension ::= SEQUENCE {
716 * extnID OBJECT IDENTIFIER,
717 * critical BOOLEAN DEFAULT FALSE,
718 * extnValue OCTET STRING }
719 */
720 mbedtls_x509_buf extn_oid = {0, 0, NULL};
721 int is_critical = 0; /* DEFAULT FALSE */
722 int ext_type = 0;
723
724 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
725 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
726 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
727
728 end_ext_data = *p + len;
729
730 /* Get extension ID */
731 if( ( ret = mbedtls_asn1_get_tag( p, end_ext_data, &extn_oid.len,
732 MBEDTLS_ASN1_OID ) ) != 0 )
733 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
734
735 extn_oid.tag = MBEDTLS_ASN1_OID;
736 extn_oid.p = *p;
737 *p += extn_oid.len;
738
739 /* Get optional critical */
740 if( ( ret = mbedtls_asn1_get_bool( p, end_ext_data, &is_critical ) ) != 0 &&
741 ( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) )
742 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
743
744 /* Data should be octet string type */
745 if( ( ret = mbedtls_asn1_get_tag( p, end_ext_data, &len,
746 MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
747 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
748
749 end_ext_octet = *p + len;
750
751 if( end_ext_octet != end_ext_data )
752 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
753 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
754
755 /*
756 * Detect supported extensions
757 */
758 ret = mbedtls_oid_get_x509_ext_type( &extn_oid, &ext_type );
759
760 if( ret != 0 )
761 {
762 /* No parser found, skip extension */
763 *p = end_ext_octet;
764
765 #if !defined(MBEDTLS_X509_ALLOW_UNSUPPORTED_CRITICAL_EXTENSION)
766 if( is_critical )
767 {
768 /* Data is marked as critical: fail */
769 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
770 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
771 }
772 #endif
773 continue;
774 }
775
776 /* Forbid repeated extensions */
777 if( ( crt->ext_types & ext_type ) != 0 )
778 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS );
779
780 crt->ext_types |= ext_type;
781
782 switch( ext_type )
783 {
784 case MBEDTLS_X509_EXT_BASIC_CONSTRAINTS:
785 /* Parse basic constraints */
786 if( ( ret = x509_get_basic_constraints( p, end_ext_octet,
787 &crt->ca_istrue, &crt->max_pathlen ) ) != 0 )
788 return( ret );
789 break;
790
791 case MBEDTLS_X509_EXT_KEY_USAGE:
792 /* Parse key usage */
793 if( ( ret = x509_get_key_usage( p, end_ext_octet,
794 &crt->key_usage ) ) != 0 )
795 return( ret );
796 break;
797
798 case MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE:
799 /* Parse extended key usage */
800 if( ( ret = x509_get_ext_key_usage( p, end_ext_octet,
801 &crt->ext_key_usage ) ) != 0 )
802 return( ret );
803 break;
804
805 case MBEDTLS_X509_EXT_SUBJECT_ALT_NAME:
806 /* Parse subject alt name */
807 if( ( ret = x509_get_subject_alt_name( p, end_ext_octet,
808 &crt->subject_alt_names ) ) != 0 )
809 return( ret );
810 break;
811
812 case MBEDTLS_X509_EXT_NS_CERT_TYPE:
813 /* Parse netscape certificate type */
814 if( ( ret = x509_get_ns_cert_type( p, end_ext_octet,
815 &crt->ns_cert_type ) ) != 0 )
816 return( ret );
817 break;
818
819 default:
820 return( MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE );
821 }
822 }
823
824 if( *p != end )
825 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
826 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
827
828 return( 0 );
829 }
830
831 /*
832 * Parse and fill a single X.509 certificate in DER format
833 */
x509_crt_parse_der_core(mbedtls_x509_crt * crt,const unsigned char * buf,size_t buflen)834 static int x509_crt_parse_der_core( mbedtls_x509_crt *crt, const unsigned char *buf,
835 size_t buflen )
836 {
837 int ret;
838 size_t len;
839 unsigned char *p, *end, *crt_end;
840 mbedtls_x509_buf sig_params1, sig_params2, sig_oid2;
841
842 memset( &sig_params1, 0, sizeof( mbedtls_x509_buf ) );
843 memset( &sig_params2, 0, sizeof( mbedtls_x509_buf ) );
844 memset( &sig_oid2, 0, sizeof( mbedtls_x509_buf ) );
845
846 /*
847 * Check for valid input
848 */
849 if( crt == NULL || buf == NULL )
850 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
851
852 // Use the original buffer until we figure out actual length
853 p = (unsigned char*) buf;
854 len = buflen;
855 end = p + len;
856
857 /*
858 * Certificate ::= SEQUENCE {
859 * tbsCertificate TBSCertificate,
860 * signatureAlgorithm AlgorithmIdentifier,
861 * signatureValue BIT STRING }
862 */
863 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
864 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
865 {
866 mbedtls_x509_crt_free( crt );
867 return( MBEDTLS_ERR_X509_INVALID_FORMAT );
868 }
869
870 if( len > (size_t) ( end - p ) )
871 {
872 mbedtls_x509_crt_free( crt );
873 return( MBEDTLS_ERR_X509_INVALID_FORMAT +
874 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
875 }
876 crt_end = p + len;
877
878 // Create and populate a new buffer for the raw field
879 crt->raw.len = crt_end - buf;
880 crt->raw.p = p = mbedtls_calloc( 1, crt->raw.len );
881 if( p == NULL )
882 return( MBEDTLS_ERR_X509_ALLOC_FAILED );
883
884 memcpy( p, buf, crt->raw.len );
885
886 // Direct pointers to the new buffer
887 p += crt->raw.len - len;
888 end = crt_end = p + len;
889
890 /*
891 * TBSCertificate ::= SEQUENCE {
892 */
893 crt->tbs.p = p;
894
895 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
896 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
897 {
898 mbedtls_x509_crt_free( crt );
899 return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
900 }
901
902 end = p + len;
903 crt->tbs.len = end - crt->tbs.p;
904
905 /*
906 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
907 *
908 * CertificateSerialNumber ::= INTEGER
909 *
910 * signature AlgorithmIdentifier
911 */
912 if( ( ret = x509_get_version( &p, end, &crt->version ) ) != 0 ||
913 ( ret = mbedtls_x509_get_serial( &p, end, &crt->serial ) ) != 0 ||
914 ( ret = mbedtls_x509_get_alg( &p, end, &crt->sig_oid,
915 &sig_params1 ) ) != 0 )
916 {
917 mbedtls_x509_crt_free( crt );
918 return( ret );
919 }
920
921 if( crt->version < 0 || crt->version > 2 )
922 {
923 mbedtls_x509_crt_free( crt );
924 return( MBEDTLS_ERR_X509_UNKNOWN_VERSION );
925 }
926
927 crt->version++;
928
929 if( ( ret = mbedtls_x509_get_sig_alg( &crt->sig_oid, &sig_params1,
930 &crt->sig_md, &crt->sig_pk,
931 &crt->sig_opts ) ) != 0 )
932 {
933 mbedtls_x509_crt_free( crt );
934 return( ret );
935 }
936
937 /*
938 * issuer Name
939 */
940 crt->issuer_raw.p = p;
941
942 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
943 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
944 {
945 mbedtls_x509_crt_free( crt );
946 return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
947 }
948
949 if( ( ret = mbedtls_x509_get_name( &p, p + len, &crt->issuer ) ) != 0 )
950 {
951 mbedtls_x509_crt_free( crt );
952 return( ret );
953 }
954
955 crt->issuer_raw.len = p - crt->issuer_raw.p;
956
957 /*
958 * Validity ::= SEQUENCE {
959 * notBefore Time,
960 * notAfter Time }
961 *
962 */
963 if( ( ret = x509_get_dates( &p, end, &crt->valid_from,
964 &crt->valid_to ) ) != 0 )
965 {
966 mbedtls_x509_crt_free( crt );
967 return( ret );
968 }
969
970 /*
971 * subject Name
972 */
973 crt->subject_raw.p = p;
974
975 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
976 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
977 {
978 mbedtls_x509_crt_free( crt );
979 return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
980 }
981
982 if( len && ( ret = mbedtls_x509_get_name( &p, p + len, &crt->subject ) ) != 0 )
983 {
984 mbedtls_x509_crt_free( crt );
985 return( ret );
986 }
987
988 crt->subject_raw.len = p - crt->subject_raw.p;
989
990 /*
991 * SubjectPublicKeyInfo
992 */
993 if( ( ret = mbedtls_pk_parse_subpubkey( &p, end, &crt->pk ) ) != 0 )
994 {
995 mbedtls_x509_crt_free( crt );
996 return( ret );
997 }
998
999 /*
1000 * issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
1001 * -- If present, version shall be v2 or v3
1002 * subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
1003 * -- If present, version shall be v2 or v3
1004 * extensions [3] EXPLICIT Extensions OPTIONAL
1005 * -- If present, version shall be v3
1006 */
1007 if( crt->version == 2 || crt->version == 3 )
1008 {
1009 ret = x509_get_uid( &p, end, &crt->issuer_id, 1 );
1010 if( ret != 0 )
1011 {
1012 mbedtls_x509_crt_free( crt );
1013 return( ret );
1014 }
1015 }
1016
1017 if( crt->version == 2 || crt->version == 3 )
1018 {
1019 ret = x509_get_uid( &p, end, &crt->subject_id, 2 );
1020 if( ret != 0 )
1021 {
1022 mbedtls_x509_crt_free( crt );
1023 return( ret );
1024 }
1025 }
1026
1027 #if !defined(MBEDTLS_X509_ALLOW_EXTENSIONS_NON_V3)
1028 if( crt->version == 3 )
1029 #endif
1030 {
1031 ret = x509_get_crt_ext( &p, end, crt );
1032 if( ret != 0 )
1033 {
1034 mbedtls_x509_crt_free( crt );
1035 return( ret );
1036 }
1037 }
1038
1039 if( p != end )
1040 {
1041 mbedtls_x509_crt_free( crt );
1042 return( MBEDTLS_ERR_X509_INVALID_FORMAT +
1043 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
1044 }
1045
1046 end = crt_end;
1047
1048 /*
1049 * }
1050 * -- end of TBSCertificate
1051 *
1052 * signatureAlgorithm AlgorithmIdentifier,
1053 * signatureValue BIT STRING
1054 */
1055 if( ( ret = mbedtls_x509_get_alg( &p, end, &sig_oid2, &sig_params2 ) ) != 0 )
1056 {
1057 mbedtls_x509_crt_free( crt );
1058 return( ret );
1059 }
1060
1061 if( crt->sig_oid.len != sig_oid2.len ||
1062 memcmp( crt->sig_oid.p, sig_oid2.p, crt->sig_oid.len ) != 0 ||
1063 sig_params1.len != sig_params2.len ||
1064 ( sig_params1.len != 0 &&
1065 memcmp( sig_params1.p, sig_params2.p, sig_params1.len ) != 0 ) )
1066 {
1067 mbedtls_x509_crt_free( crt );
1068 return( MBEDTLS_ERR_X509_SIG_MISMATCH );
1069 }
1070
1071 if( ( ret = mbedtls_x509_get_sig( &p, end, &crt->sig ) ) != 0 )
1072 {
1073 mbedtls_x509_crt_free( crt );
1074 return( ret );
1075 }
1076
1077 if( p != end )
1078 {
1079 mbedtls_x509_crt_free( crt );
1080 return( MBEDTLS_ERR_X509_INVALID_FORMAT +
1081 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
1082 }
1083
1084 return( 0 );
1085 }
1086
1087 /*
1088 * Parse one X.509 certificate in DER format from a buffer and add them to a
1089 * chained list
1090 */
mbedtls_x509_crt_parse_der(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)1091 int mbedtls_x509_crt_parse_der( mbedtls_x509_crt *chain, const unsigned char *buf,
1092 size_t buflen )
1093 {
1094 int ret;
1095 mbedtls_x509_crt *crt = chain, *prev = NULL;
1096
1097 /*
1098 * Check for valid input
1099 */
1100 if( crt == NULL || buf == NULL )
1101 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1102
1103 while( crt->version != 0 && crt->next != NULL )
1104 {
1105 prev = crt;
1106 crt = crt->next;
1107 }
1108
1109 /*
1110 * Add new certificate on the end of the chain if needed.
1111 */
1112 if( crt->version != 0 && crt->next == NULL )
1113 {
1114 crt->next = mbedtls_calloc( 1, sizeof( mbedtls_x509_crt ) );
1115
1116 if( crt->next == NULL )
1117 return( MBEDTLS_ERR_X509_ALLOC_FAILED );
1118
1119 prev = crt;
1120 mbedtls_x509_crt_init( crt->next );
1121 crt = crt->next;
1122 }
1123
1124 if( ( ret = x509_crt_parse_der_core( crt, buf, buflen ) ) != 0 )
1125 {
1126 if( prev )
1127 prev->next = NULL;
1128
1129 if( crt != chain )
1130 mbedtls_free( crt );
1131
1132 return( ret );
1133 }
1134
1135 return( 0 );
1136 }
1137
1138 /*
1139 * Parse one or more PEM certificates from a buffer and add them to the chained
1140 * list
1141 */
mbedtls_x509_crt_parse(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)1142 int mbedtls_x509_crt_parse( mbedtls_x509_crt *chain, const unsigned char *buf, size_t buflen )
1143 {
1144 #if defined(MBEDTLS_PEM_PARSE_C)
1145 int success = 0, first_error = 0, total_failed = 0;
1146 int buf_format = MBEDTLS_X509_FORMAT_DER;
1147 #endif
1148
1149 /*
1150 * Check for valid input
1151 */
1152 if( chain == NULL || buf == NULL )
1153 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1154
1155 /*
1156 * Determine buffer content. Buffer contains either one DER certificate or
1157 * one or more PEM certificates.
1158 */
1159 #if defined(MBEDTLS_PEM_PARSE_C)
1160 if( buflen != 0 && buf[buflen - 1] == '\0' &&
1161 strstr( (const char *) buf, "-----BEGIN CERTIFICATE-----" ) != NULL )
1162 {
1163 buf_format = MBEDTLS_X509_FORMAT_PEM;
1164 }
1165
1166 if( buf_format == MBEDTLS_X509_FORMAT_DER )
1167 return mbedtls_x509_crt_parse_der( chain, buf, buflen );
1168 #else
1169 return mbedtls_x509_crt_parse_der( chain, buf, buflen );
1170 #endif
1171
1172 #if defined(MBEDTLS_PEM_PARSE_C)
1173 if( buf_format == MBEDTLS_X509_FORMAT_PEM )
1174 {
1175 int ret;
1176 mbedtls_pem_context pem;
1177
1178 /* 1 rather than 0 since the terminating NULL byte is counted in */
1179 while( buflen > 1 )
1180 {
1181 size_t use_len;
1182 mbedtls_pem_init( &pem );
1183
1184 /* If we get there, we know the string is null-terminated */
1185 ret = mbedtls_pem_read_buffer( &pem,
1186 "-----BEGIN CERTIFICATE-----",
1187 "-----END CERTIFICATE-----",
1188 buf, NULL, 0, &use_len );
1189
1190 if( ret == 0 )
1191 {
1192 /*
1193 * Was PEM encoded
1194 */
1195 buflen -= use_len;
1196 buf += use_len;
1197 }
1198 else if( ret == MBEDTLS_ERR_PEM_BAD_INPUT_DATA )
1199 {
1200 return( ret );
1201 }
1202 else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
1203 {
1204 mbedtls_pem_free( &pem );
1205
1206 /*
1207 * PEM header and footer were found
1208 */
1209 buflen -= use_len;
1210 buf += use_len;
1211
1212 if( first_error == 0 )
1213 first_error = ret;
1214
1215 total_failed++;
1216 continue;
1217 }
1218 else
1219 break;
1220
1221 ret = mbedtls_x509_crt_parse_der( chain, pem.buf, pem.buflen );
1222
1223 mbedtls_pem_free( &pem );
1224
1225 if( ret != 0 )
1226 {
1227 /*
1228 * Quit parsing on a memory error
1229 */
1230 if( ret == MBEDTLS_ERR_X509_ALLOC_FAILED )
1231 return( ret );
1232
1233 if( first_error == 0 )
1234 first_error = ret;
1235
1236 total_failed++;
1237 continue;
1238 }
1239
1240 success = 1;
1241 }
1242 }
1243
1244 if( success )
1245 return( total_failed );
1246 else if( first_error )
1247 return( first_error );
1248 else
1249 return( MBEDTLS_ERR_X509_CERT_UNKNOWN_FORMAT );
1250 #endif /* MBEDTLS_PEM_PARSE_C */
1251 }
1252
1253 #if defined(MBEDTLS_FS_IO)
1254 /*
1255 * Load one or more certificates and add them to the chained list
1256 */
mbedtls_x509_crt_parse_file(mbedtls_x509_crt * chain,const char * path)1257 int mbedtls_x509_crt_parse_file( mbedtls_x509_crt *chain, const char *path )
1258 {
1259 int ret;
1260 size_t n;
1261 unsigned char *buf;
1262
1263 if( ( ret = mbedtls_pk_load_file( path, &buf, &n ) ) != 0 )
1264 return( ret );
1265
1266 ret = mbedtls_x509_crt_parse( chain, buf, n );
1267
1268 mbedtls_platform_zeroize( buf, n );
1269 mbedtls_free( buf );
1270
1271 return( ret );
1272 }
1273
mbedtls_x509_crt_parse_path(mbedtls_x509_crt * chain,const char * path)1274 int mbedtls_x509_crt_parse_path( mbedtls_x509_crt *chain, const char *path )
1275 {
1276 int ret = 0;
1277 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
1278 int w_ret;
1279 WCHAR szDir[MAX_PATH];
1280 char filename[MAX_PATH];
1281 char *p;
1282 size_t len = strlen( path );
1283
1284 WIN32_FIND_DATAW file_data;
1285 HANDLE hFind;
1286
1287 if( len > MAX_PATH - 3 )
1288 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1289
1290 memset( szDir, 0, sizeof(szDir) );
1291 memset( filename, 0, MAX_PATH );
1292 memcpy( filename, path, len );
1293 filename[len++] = '\\';
1294 p = filename + len;
1295 filename[len++] = '*';
1296
1297 w_ret = MultiByteToWideChar( CP_ACP, 0, filename, (int)len, szDir,
1298 MAX_PATH - 3 );
1299 if( w_ret == 0 )
1300 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1301
1302 hFind = FindFirstFileW( szDir, &file_data );
1303 if( hFind == INVALID_HANDLE_VALUE )
1304 return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
1305
1306 len = MAX_PATH - len;
1307 do
1308 {
1309 memset( p, 0, len );
1310
1311 if( file_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY )
1312 continue;
1313
1314 w_ret = WideCharToMultiByte( CP_ACP, 0, file_data.cFileName,
1315 lstrlenW( file_data.cFileName ),
1316 p, (int) len - 1,
1317 NULL, NULL );
1318 if( w_ret == 0 )
1319 {
1320 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1321 goto cleanup;
1322 }
1323
1324 w_ret = mbedtls_x509_crt_parse_file( chain, filename );
1325 if( w_ret < 0 )
1326 ret++;
1327 else
1328 ret += w_ret;
1329 }
1330 while( FindNextFileW( hFind, &file_data ) != 0 );
1331
1332 if( GetLastError() != ERROR_NO_MORE_FILES )
1333 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1334
1335 cleanup:
1336 FindClose( hFind );
1337 #else /* _WIN32 */
1338 int t_ret;
1339 int snp_ret;
1340 struct stat sb;
1341 struct dirent *entry;
1342 char entry_name[MBEDTLS_X509_MAX_FILE_PATH_LEN];
1343 DIR *dir = opendir( path );
1344
1345 if( dir == NULL )
1346 return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
1347
1348 #if defined(MBEDTLS_THREADING_C)
1349 if( ( ret = mbedtls_mutex_lock( &mbedtls_threading_readdir_mutex ) ) != 0 )
1350 {
1351 closedir( dir );
1352 return( ret );
1353 }
1354 #endif /* MBEDTLS_THREADING_C */
1355
1356 while( ( entry = readdir( dir ) ) != NULL )
1357 {
1358 snp_ret = mbedtls_snprintf( entry_name, sizeof entry_name,
1359 "%s/%s", path, entry->d_name );
1360
1361 if( snp_ret < 0 || (size_t)snp_ret >= sizeof entry_name )
1362 {
1363 ret = MBEDTLS_ERR_X509_BUFFER_TOO_SMALL;
1364 goto cleanup;
1365 }
1366 else if( stat( entry_name, &sb ) == -1 )
1367 {
1368 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1369 goto cleanup;
1370 }
1371
1372 if( !S_ISREG( sb.st_mode ) )
1373 continue;
1374
1375 // Ignore parse errors
1376 //
1377 t_ret = mbedtls_x509_crt_parse_file( chain, entry_name );
1378 if( t_ret < 0 )
1379 ret++;
1380 else
1381 ret += t_ret;
1382 }
1383
1384 cleanup:
1385 closedir( dir );
1386
1387 #if defined(MBEDTLS_THREADING_C)
1388 if( mbedtls_mutex_unlock( &mbedtls_threading_readdir_mutex ) != 0 )
1389 ret = MBEDTLS_ERR_THREADING_MUTEX_ERROR;
1390 #endif /* MBEDTLS_THREADING_C */
1391
1392 #endif /* _WIN32 */
1393
1394 return( ret );
1395 }
1396 #endif /* MBEDTLS_FS_IO */
1397
x509_info_subject_alt_name(char ** buf,size_t * size,const mbedtls_x509_sequence * subject_alt_name)1398 static int x509_info_subject_alt_name( char **buf, size_t *size,
1399 const mbedtls_x509_sequence *subject_alt_name )
1400 {
1401 size_t i;
1402 size_t n = *size;
1403 char *p = *buf;
1404 const mbedtls_x509_sequence *cur = subject_alt_name;
1405 const char *sep = "";
1406 size_t sep_len = 0;
1407
1408 while( cur != NULL )
1409 {
1410 if( cur->buf.len + sep_len >= n )
1411 {
1412 *p = '\0';
1413 return( MBEDTLS_ERR_X509_BUFFER_TOO_SMALL );
1414 }
1415
1416 n -= cur->buf.len + sep_len;
1417 for( i = 0; i < sep_len; i++ )
1418 *p++ = sep[i];
1419 for( i = 0; i < cur->buf.len; i++ )
1420 *p++ = cur->buf.p[i];
1421
1422 sep = ", ";
1423 sep_len = 2;
1424
1425 cur = cur->next;
1426 }
1427
1428 *p = '\0';
1429
1430 *size = n;
1431 *buf = p;
1432
1433 return( 0 );
1434 }
1435
1436 #define PRINT_ITEM(i) \
1437 { \
1438 ret = mbedtls_snprintf( p, n, "%s" i, sep ); \
1439 MBEDTLS_X509_SAFE_SNPRINTF; \
1440 sep = ", "; \
1441 }
1442
1443 #define CERT_TYPE(type,name) \
1444 if( ns_cert_type & type ) \
1445 PRINT_ITEM( name );
1446
x509_info_cert_type(char ** buf,size_t * size,unsigned char ns_cert_type)1447 static int x509_info_cert_type( char **buf, size_t *size,
1448 unsigned char ns_cert_type )
1449 {
1450 int ret;
1451 size_t n = *size;
1452 char *p = *buf;
1453 const char *sep = "";
1454
1455 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_CLIENT, "SSL Client" );
1456 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER, "SSL Server" );
1457 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_EMAIL, "Email" );
1458 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING, "Object Signing" );
1459 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_RESERVED, "Reserved" );
1460 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_CA, "SSL CA" );
1461 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_EMAIL_CA, "Email CA" );
1462 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING_CA, "Object Signing CA" );
1463
1464 *size = n;
1465 *buf = p;
1466
1467 return( 0 );
1468 }
1469
1470 #define KEY_USAGE(code,name) \
1471 if( key_usage & code ) \
1472 PRINT_ITEM( name );
1473
x509_info_key_usage(char ** buf,size_t * size,unsigned int key_usage)1474 static int x509_info_key_usage( char **buf, size_t *size,
1475 unsigned int key_usage )
1476 {
1477 int ret;
1478 size_t n = *size;
1479 char *p = *buf;
1480 const char *sep = "";
1481
1482 KEY_USAGE( MBEDTLS_X509_KU_DIGITAL_SIGNATURE, "Digital Signature" );
1483 KEY_USAGE( MBEDTLS_X509_KU_NON_REPUDIATION, "Non Repudiation" );
1484 KEY_USAGE( MBEDTLS_X509_KU_KEY_ENCIPHERMENT, "Key Encipherment" );
1485 KEY_USAGE( MBEDTLS_X509_KU_DATA_ENCIPHERMENT, "Data Encipherment" );
1486 KEY_USAGE( MBEDTLS_X509_KU_KEY_AGREEMENT, "Key Agreement" );
1487 KEY_USAGE( MBEDTLS_X509_KU_KEY_CERT_SIGN, "Key Cert Sign" );
1488 KEY_USAGE( MBEDTLS_X509_KU_CRL_SIGN, "CRL Sign" );
1489 KEY_USAGE( MBEDTLS_X509_KU_ENCIPHER_ONLY, "Encipher Only" );
1490 KEY_USAGE( MBEDTLS_X509_KU_DECIPHER_ONLY, "Decipher Only" );
1491
1492 *size = n;
1493 *buf = p;
1494
1495 return( 0 );
1496 }
1497
x509_info_ext_key_usage(char ** buf,size_t * size,const mbedtls_x509_sequence * extended_key_usage)1498 static int x509_info_ext_key_usage( char **buf, size_t *size,
1499 const mbedtls_x509_sequence *extended_key_usage )
1500 {
1501 int ret;
1502 const char *desc;
1503 size_t n = *size;
1504 char *p = *buf;
1505 const mbedtls_x509_sequence *cur = extended_key_usage;
1506 const char *sep = "";
1507
1508 while( cur != NULL )
1509 {
1510 if( mbedtls_oid_get_extended_key_usage( &cur->buf, &desc ) != 0 )
1511 desc = "???";
1512
1513 ret = mbedtls_snprintf( p, n, "%s%s", sep, desc );
1514 MBEDTLS_X509_SAFE_SNPRINTF;
1515
1516 sep = ", ";
1517
1518 cur = cur->next;
1519 }
1520
1521 *size = n;
1522 *buf = p;
1523
1524 return( 0 );
1525 }
1526
1527 /*
1528 * Return an informational string about the certificate.
1529 */
1530 #define BEFORE_COLON 18
1531 #define BC "18"
mbedtls_x509_crt_info(char * buf,size_t size,const char * prefix,const mbedtls_x509_crt * crt)1532 int mbedtls_x509_crt_info( char *buf, size_t size, const char *prefix,
1533 const mbedtls_x509_crt *crt )
1534 {
1535 int ret;
1536 size_t n;
1537 char *p;
1538 char key_size_str[BEFORE_COLON];
1539
1540 p = buf;
1541 n = size;
1542
1543 if( NULL == crt )
1544 {
1545 ret = mbedtls_snprintf( p, n, "\nCertificate is uninitialised!\n" );
1546 MBEDTLS_X509_SAFE_SNPRINTF;
1547
1548 return( (int) ( size - n ) );
1549 }
1550
1551 ret = mbedtls_snprintf( p, n, "%scert. version : %d\n",
1552 prefix, crt->version );
1553 MBEDTLS_X509_SAFE_SNPRINTF;
1554 ret = mbedtls_snprintf( p, n, "%sserial number : ",
1555 prefix );
1556 MBEDTLS_X509_SAFE_SNPRINTF;
1557
1558 ret = mbedtls_x509_serial_gets( p, n, &crt->serial );
1559 MBEDTLS_X509_SAFE_SNPRINTF;
1560
1561 ret = mbedtls_snprintf( p, n, "\n%sissuer name : ", prefix );
1562 MBEDTLS_X509_SAFE_SNPRINTF;
1563 ret = mbedtls_x509_dn_gets( p, n, &crt->issuer );
1564 MBEDTLS_X509_SAFE_SNPRINTF;
1565
1566 ret = mbedtls_snprintf( p, n, "\n%ssubject name : ", prefix );
1567 MBEDTLS_X509_SAFE_SNPRINTF;
1568 ret = mbedtls_x509_dn_gets( p, n, &crt->subject );
1569 MBEDTLS_X509_SAFE_SNPRINTF;
1570
1571 ret = mbedtls_snprintf( p, n, "\n%sissued on : " \
1572 "%04d-%02d-%02d %02d:%02d:%02d", prefix,
1573 crt->valid_from.year, crt->valid_from.mon,
1574 crt->valid_from.day, crt->valid_from.hour,
1575 crt->valid_from.min, crt->valid_from.sec );
1576 MBEDTLS_X509_SAFE_SNPRINTF;
1577
1578 ret = mbedtls_snprintf( p, n, "\n%sexpires on : " \
1579 "%04d-%02d-%02d %02d:%02d:%02d", prefix,
1580 crt->valid_to.year, crt->valid_to.mon,
1581 crt->valid_to.day, crt->valid_to.hour,
1582 crt->valid_to.min, crt->valid_to.sec );
1583 MBEDTLS_X509_SAFE_SNPRINTF;
1584
1585 ret = mbedtls_snprintf( p, n, "\n%ssigned using : ", prefix );
1586 MBEDTLS_X509_SAFE_SNPRINTF;
1587
1588 ret = mbedtls_x509_sig_alg_gets( p, n, &crt->sig_oid, crt->sig_pk,
1589 crt->sig_md, crt->sig_opts );
1590 MBEDTLS_X509_SAFE_SNPRINTF;
1591
1592 /* Key size */
1593 if( ( ret = mbedtls_x509_key_size_helper( key_size_str, BEFORE_COLON,
1594 mbedtls_pk_get_name( &crt->pk ) ) ) != 0 )
1595 {
1596 return( ret );
1597 }
1598
1599 ret = mbedtls_snprintf( p, n, "\n%s%-" BC "s: %d bits", prefix, key_size_str,
1600 (int) mbedtls_pk_get_bitlen( &crt->pk ) );
1601 MBEDTLS_X509_SAFE_SNPRINTF;
1602
1603 /*
1604 * Optional extensions
1605 */
1606
1607 if( crt->ext_types & MBEDTLS_X509_EXT_BASIC_CONSTRAINTS )
1608 {
1609 ret = mbedtls_snprintf( p, n, "\n%sbasic constraints : CA=%s", prefix,
1610 crt->ca_istrue ? "true" : "false" );
1611 MBEDTLS_X509_SAFE_SNPRINTF;
1612
1613 if( crt->max_pathlen > 0 )
1614 {
1615 ret = mbedtls_snprintf( p, n, ", max_pathlen=%d", crt->max_pathlen - 1 );
1616 MBEDTLS_X509_SAFE_SNPRINTF;
1617 }
1618 }
1619
1620 if( crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME )
1621 {
1622 ret = mbedtls_snprintf( p, n, "\n%ssubject alt name : ", prefix );
1623 MBEDTLS_X509_SAFE_SNPRINTF;
1624
1625 if( ( ret = x509_info_subject_alt_name( &p, &n,
1626 &crt->subject_alt_names ) ) != 0 )
1627 return( ret );
1628 }
1629
1630 if( crt->ext_types & MBEDTLS_X509_EXT_NS_CERT_TYPE )
1631 {
1632 ret = mbedtls_snprintf( p, n, "\n%scert. type : ", prefix );
1633 MBEDTLS_X509_SAFE_SNPRINTF;
1634
1635 if( ( ret = x509_info_cert_type( &p, &n, crt->ns_cert_type ) ) != 0 )
1636 return( ret );
1637 }
1638
1639 if( crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE )
1640 {
1641 ret = mbedtls_snprintf( p, n, "\n%skey usage : ", prefix );
1642 MBEDTLS_X509_SAFE_SNPRINTF;
1643
1644 if( ( ret = x509_info_key_usage( &p, &n, crt->key_usage ) ) != 0 )
1645 return( ret );
1646 }
1647
1648 if( crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE )
1649 {
1650 ret = mbedtls_snprintf( p, n, "\n%sext key usage : ", prefix );
1651 MBEDTLS_X509_SAFE_SNPRINTF;
1652
1653 if( ( ret = x509_info_ext_key_usage( &p, &n,
1654 &crt->ext_key_usage ) ) != 0 )
1655 return( ret );
1656 }
1657
1658 ret = mbedtls_snprintf( p, n, "\n" );
1659 MBEDTLS_X509_SAFE_SNPRINTF;
1660
1661 return( (int) ( size - n ) );
1662 }
1663
1664 struct x509_crt_verify_string {
1665 int code;
1666 const char *string;
1667 };
1668
1669 static const struct x509_crt_verify_string x509_crt_verify_strings[] = {
1670 { MBEDTLS_X509_BADCERT_EXPIRED, "The certificate validity has expired" },
1671 { MBEDTLS_X509_BADCERT_REVOKED, "The certificate has been revoked (is on a CRL)" },
1672 { MBEDTLS_X509_BADCERT_CN_MISMATCH, "The certificate Common Name (CN) does not match with the expected CN" },
1673 { MBEDTLS_X509_BADCERT_NOT_TRUSTED, "The certificate is not correctly signed by the trusted CA" },
1674 { MBEDTLS_X509_BADCRL_NOT_TRUSTED, "The CRL is not correctly signed by the trusted CA" },
1675 { MBEDTLS_X509_BADCRL_EXPIRED, "The CRL is expired" },
1676 { MBEDTLS_X509_BADCERT_MISSING, "Certificate was missing" },
1677 { MBEDTLS_X509_BADCERT_SKIP_VERIFY, "Certificate verification was skipped" },
1678 { MBEDTLS_X509_BADCERT_OTHER, "Other reason (can be used by verify callback)" },
1679 { MBEDTLS_X509_BADCERT_FUTURE, "The certificate validity starts in the future" },
1680 { MBEDTLS_X509_BADCRL_FUTURE, "The CRL is from the future" },
1681 { MBEDTLS_X509_BADCERT_KEY_USAGE, "Usage does not match the keyUsage extension" },
1682 { MBEDTLS_X509_BADCERT_EXT_KEY_USAGE, "Usage does not match the extendedKeyUsage extension" },
1683 { MBEDTLS_X509_BADCERT_NS_CERT_TYPE, "Usage does not match the nsCertType extension" },
1684 { MBEDTLS_X509_BADCERT_BAD_MD, "The certificate is signed with an unacceptable hash." },
1685 { MBEDTLS_X509_BADCERT_BAD_PK, "The certificate is signed with an unacceptable PK alg (eg RSA vs ECDSA)." },
1686 { MBEDTLS_X509_BADCERT_BAD_KEY, "The certificate is signed with an unacceptable key (eg bad curve, RSA too short)." },
1687 { MBEDTLS_X509_BADCRL_BAD_MD, "The CRL is signed with an unacceptable hash." },
1688 { MBEDTLS_X509_BADCRL_BAD_PK, "The CRL is signed with an unacceptable PK alg (eg RSA vs ECDSA)." },
1689 { MBEDTLS_X509_BADCRL_BAD_KEY, "The CRL is signed with an unacceptable key (eg bad curve, RSA too short)." },
1690 { 0, NULL }
1691 };
1692
mbedtls_x509_crt_verify_info(char * buf,size_t size,const char * prefix,uint32_t flags)1693 int mbedtls_x509_crt_verify_info( char *buf, size_t size, const char *prefix,
1694 uint32_t flags )
1695 {
1696 int ret;
1697 const struct x509_crt_verify_string *cur;
1698 char *p = buf;
1699 size_t n = size;
1700
1701 for( cur = x509_crt_verify_strings; cur->string != NULL ; cur++ )
1702 {
1703 if( ( flags & cur->code ) == 0 )
1704 continue;
1705
1706 ret = mbedtls_snprintf( p, n, "%s%s\n", prefix, cur->string );
1707 MBEDTLS_X509_SAFE_SNPRINTF;
1708 flags ^= cur->code;
1709 }
1710
1711 if( flags != 0 )
1712 {
1713 ret = mbedtls_snprintf( p, n, "%sUnknown reason "
1714 "(this should not happen)\n", prefix );
1715 MBEDTLS_X509_SAFE_SNPRINTF;
1716 }
1717
1718 return( (int) ( size - n ) );
1719 }
1720
1721 #if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
mbedtls_x509_crt_check_key_usage(const mbedtls_x509_crt * crt,unsigned int usage)1722 int mbedtls_x509_crt_check_key_usage( const mbedtls_x509_crt *crt,
1723 unsigned int usage )
1724 {
1725 unsigned int usage_must, usage_may;
1726 unsigned int may_mask = MBEDTLS_X509_KU_ENCIPHER_ONLY
1727 | MBEDTLS_X509_KU_DECIPHER_ONLY;
1728
1729 if( ( crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE ) == 0 )
1730 return( 0 );
1731
1732 usage_must = usage & ~may_mask;
1733
1734 if( ( ( crt->key_usage & ~may_mask ) & usage_must ) != usage_must )
1735 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1736
1737 usage_may = usage & may_mask;
1738
1739 if( ( ( crt->key_usage & may_mask ) | usage_may ) != usage_may )
1740 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1741
1742 return( 0 );
1743 }
1744 #endif
1745
1746 #if defined(MBEDTLS_X509_CHECK_EXTENDED_KEY_USAGE)
mbedtls_x509_crt_check_extended_key_usage(const mbedtls_x509_crt * crt,const char * usage_oid,size_t usage_len)1747 int mbedtls_x509_crt_check_extended_key_usage( const mbedtls_x509_crt *crt,
1748 const char *usage_oid,
1749 size_t usage_len )
1750 {
1751 const mbedtls_x509_sequence *cur;
1752
1753 /* Extension is not mandatory, absent means no restriction */
1754 if( ( crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE ) == 0 )
1755 return( 0 );
1756
1757 /*
1758 * Look for the requested usage (or wildcard ANY) in our list
1759 */
1760 for( cur = &crt->ext_key_usage; cur != NULL; cur = cur->next )
1761 {
1762 const mbedtls_x509_buf *cur_oid = &cur->buf;
1763
1764 if( cur_oid->len == usage_len &&
1765 memcmp( cur_oid->p, usage_oid, usage_len ) == 0 )
1766 {
1767 return( 0 );
1768 }
1769
1770 if( MBEDTLS_OID_CMP( MBEDTLS_OID_ANY_EXTENDED_KEY_USAGE, cur_oid ) == 0 )
1771 return( 0 );
1772 }
1773
1774 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1775 }
1776 #endif /* MBEDTLS_X509_CHECK_EXTENDED_KEY_USAGE */
1777
1778 #if defined(MBEDTLS_X509_CRL_PARSE_C)
1779 /*
1780 * Return 1 if the certificate is revoked, or 0 otherwise.
1781 */
mbedtls_x509_crt_is_revoked(const mbedtls_x509_crt * crt,const mbedtls_x509_crl * crl)1782 int mbedtls_x509_crt_is_revoked( const mbedtls_x509_crt *crt, const mbedtls_x509_crl *crl )
1783 {
1784 const mbedtls_x509_crl_entry *cur = &crl->entry;
1785
1786 while( cur != NULL && cur->serial.len != 0 )
1787 {
1788 if( crt->serial.len == cur->serial.len &&
1789 memcmp( crt->serial.p, cur->serial.p, crt->serial.len ) == 0 )
1790 {
1791 if( mbedtls_x509_time_is_past( &cur->revocation_date ) )
1792 return( 1 );
1793 }
1794
1795 cur = cur->next;
1796 }
1797
1798 return( 0 );
1799 }
1800
1801 /*
1802 * Check that the given certificate is not revoked according to the CRL.
1803 * Skip validation if no CRL for the given CA is present.
1804 */
x509_crt_verifycrl(mbedtls_x509_crt * crt,mbedtls_x509_crt * ca,mbedtls_x509_crl * crl_list,const mbedtls_x509_crt_profile * profile)1805 static int x509_crt_verifycrl( mbedtls_x509_crt *crt, mbedtls_x509_crt *ca,
1806 mbedtls_x509_crl *crl_list,
1807 const mbedtls_x509_crt_profile *profile )
1808 {
1809 int flags = 0;
1810 unsigned char hash[MBEDTLS_MD_MAX_SIZE];
1811 const mbedtls_md_info_t *md_info;
1812
1813 if( ca == NULL )
1814 return( flags );
1815
1816 while( crl_list != NULL )
1817 {
1818 if( crl_list->version == 0 ||
1819 x509_name_cmp( &crl_list->issuer, &ca->subject ) != 0 )
1820 {
1821 crl_list = crl_list->next;
1822 continue;
1823 }
1824
1825 /*
1826 * Check if the CA is configured to sign CRLs
1827 */
1828 #if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
1829 if( mbedtls_x509_crt_check_key_usage( ca,
1830 MBEDTLS_X509_KU_CRL_SIGN ) != 0 )
1831 {
1832 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
1833 break;
1834 }
1835 #endif
1836
1837 /*
1838 * Check if CRL is correctly signed by the trusted CA
1839 */
1840 if( x509_profile_check_md_alg( profile, crl_list->sig_md ) != 0 )
1841 flags |= MBEDTLS_X509_BADCRL_BAD_MD;
1842
1843 if( x509_profile_check_pk_alg( profile, crl_list->sig_pk ) != 0 )
1844 flags |= MBEDTLS_X509_BADCRL_BAD_PK;
1845
1846 md_info = mbedtls_md_info_from_type( crl_list->sig_md );
1847 if( mbedtls_md( md_info, crl_list->tbs.p, crl_list->tbs.len, hash ) != 0 )
1848 {
1849 /* Note: this can't happen except after an internal error */
1850 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
1851 break;
1852 }
1853
1854 if( x509_profile_check_key( profile, &ca->pk ) != 0 )
1855 flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
1856
1857 if( mbedtls_pk_verify_ext( crl_list->sig_pk, crl_list->sig_opts, &ca->pk,
1858 crl_list->sig_md, hash, mbedtls_md_get_size( md_info ),
1859 crl_list->sig.p, crl_list->sig.len ) != 0 )
1860 {
1861 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
1862 break;
1863 }
1864
1865 /*
1866 * Check for validity of CRL (Do not drop out)
1867 */
1868 if( mbedtls_x509_time_is_past( &crl_list->next_update ) )
1869 flags |= MBEDTLS_X509_BADCRL_EXPIRED;
1870
1871 if( mbedtls_x509_time_is_future( &crl_list->this_update ) )
1872 flags |= MBEDTLS_X509_BADCRL_FUTURE;
1873
1874 /*
1875 * Check if certificate is revoked
1876 */
1877 if( mbedtls_x509_crt_is_revoked( crt, crl_list ) )
1878 {
1879 flags |= MBEDTLS_X509_BADCERT_REVOKED;
1880 break;
1881 }
1882
1883 crl_list = crl_list->next;
1884 }
1885
1886 return( flags );
1887 }
1888 #endif /* MBEDTLS_X509_CRL_PARSE_C */
1889
1890 /*
1891 * Check the signature of a certificate by its parent
1892 */
x509_crt_check_signature(const mbedtls_x509_crt * child,mbedtls_x509_crt * parent,mbedtls_x509_crt_restart_ctx * rs_ctx)1893 static int x509_crt_check_signature( const mbedtls_x509_crt *child,
1894 mbedtls_x509_crt *parent,
1895 mbedtls_x509_crt_restart_ctx *rs_ctx )
1896 {
1897 const mbedtls_md_info_t *md_info;
1898 unsigned char hash[MBEDTLS_MD_MAX_SIZE];
1899
1900 md_info = mbedtls_md_info_from_type( child->sig_md );
1901 if( mbedtls_md( md_info, child->tbs.p, child->tbs.len, hash ) != 0 )
1902 {
1903 /* Note: this can't happen except after an internal error */
1904 return( -1 );
1905 }
1906
1907 /* Skip expensive computation on obvious mismatch */
1908 if( ! mbedtls_pk_can_do( &parent->pk, child->sig_pk ) )
1909 return( -1 );
1910
1911 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
1912 if( rs_ctx != NULL && child->sig_pk == MBEDTLS_PK_ECDSA )
1913 {
1914 return( mbedtls_pk_verify_restartable( &parent->pk,
1915 child->sig_md, hash, mbedtls_md_get_size( md_info ),
1916 child->sig.p, child->sig.len, &rs_ctx->pk ) );
1917 }
1918 #else
1919 (void) rs_ctx;
1920 #endif
1921
1922 return( mbedtls_pk_verify_ext( child->sig_pk, child->sig_opts, &parent->pk,
1923 child->sig_md, hash, mbedtls_md_get_size( md_info ),
1924 child->sig.p, child->sig.len ) );
1925 }
1926
1927 /*
1928 * Check if 'parent' is a suitable parent (signing CA) for 'child'.
1929 * Return 0 if yes, -1 if not.
1930 *
1931 * top means parent is a locally-trusted certificate
1932 */
x509_crt_check_parent(const mbedtls_x509_crt * child,const mbedtls_x509_crt * parent,int top)1933 static int x509_crt_check_parent( const mbedtls_x509_crt *child,
1934 const mbedtls_x509_crt *parent,
1935 int top )
1936 {
1937 int need_ca_bit;
1938
1939 /* Parent must be the issuer */
1940 if( x509_name_cmp( &child->issuer, &parent->subject ) != 0 )
1941 return( -1 );
1942
1943 /* Parent must have the basicConstraints CA bit set as a general rule */
1944 need_ca_bit = 1;
1945
1946 /* Exception: v1/v2 certificates that are locally trusted. */
1947 if( top && parent->version < 3 )
1948 need_ca_bit = 0;
1949
1950 if( need_ca_bit && ! parent->ca_istrue )
1951 return( -1 );
1952
1953 #if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
1954 if( need_ca_bit &&
1955 mbedtls_x509_crt_check_key_usage( parent, MBEDTLS_X509_KU_KEY_CERT_SIGN ) != 0 )
1956 {
1957 return( -1 );
1958 }
1959 #endif
1960
1961 return( 0 );
1962 }
1963
1964 /*
1965 * Find a suitable parent for child in candidates, or return NULL.
1966 *
1967 * Here suitable is defined as:
1968 * 1. subject name matches child's issuer
1969 * 2. if necessary, the CA bit is set and key usage allows signing certs
1970 * 3. for trusted roots, the signature is correct
1971 * (for intermediates, the signature is checked and the result reported)
1972 * 4. pathlen constraints are satisfied
1973 *
1974 * If there's a suitable candidate which is also time-valid, return the first
1975 * such. Otherwise, return the first suitable candidate (or NULL if there is
1976 * none).
1977 *
1978 * The rationale for this rule is that someone could have a list of trusted
1979 * roots with two versions on the same root with different validity periods.
1980 * (At least one user reported having such a list and wanted it to just work.)
1981 * The reason we don't just require time-validity is that generally there is
1982 * only one version, and if it's expired we want the flags to state that
1983 * rather than NOT_TRUSTED, as would be the case if we required it here.
1984 *
1985 * The rationale for rule 3 (signature for trusted roots) is that users might
1986 * have two versions of the same CA with different keys in their list, and the
1987 * way we select the correct one is by checking the signature (as we don't
1988 * rely on key identifier extensions). (This is one way users might choose to
1989 * handle key rollover, another relies on self-issued certs, see [SIRO].)
1990 *
1991 * Arguments:
1992 * - [in] child: certificate for which we're looking for a parent
1993 * - [in] candidates: chained list of potential parents
1994 * - [out] r_parent: parent found (or NULL)
1995 * - [out] r_signature_is_good: 1 if child signature by parent is valid, or 0
1996 * - [in] top: 1 if candidates consists of trusted roots, ie we're at the top
1997 * of the chain, 0 otherwise
1998 * - [in] path_cnt: number of intermediates seen so far
1999 * - [in] self_cnt: number of self-signed intermediates seen so far
2000 * (will never be greater than path_cnt)
2001 * - [in-out] rs_ctx: context for restarting operations
2002 *
2003 * Return value:
2004 * - 0 on success
2005 * - MBEDTLS_ERR_ECP_IN_PROGRESS otherwise
2006 */
x509_crt_find_parent_in(mbedtls_x509_crt * child,mbedtls_x509_crt * candidates,mbedtls_x509_crt ** r_parent,int * r_signature_is_good,int top,unsigned path_cnt,unsigned self_cnt,mbedtls_x509_crt_restart_ctx * rs_ctx)2007 static int x509_crt_find_parent_in(
2008 mbedtls_x509_crt *child,
2009 mbedtls_x509_crt *candidates,
2010 mbedtls_x509_crt **r_parent,
2011 int *r_signature_is_good,
2012 int top,
2013 unsigned path_cnt,
2014 unsigned self_cnt,
2015 mbedtls_x509_crt_restart_ctx *rs_ctx )
2016 {
2017 int ret;
2018 mbedtls_x509_crt *parent, *fallback_parent;
2019 int signature_is_good, fallback_signature_is_good;
2020
2021 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2022 /* did we have something in progress? */
2023 if( rs_ctx != NULL && rs_ctx->parent != NULL )
2024 {
2025 /* restore saved state */
2026 parent = rs_ctx->parent;
2027 fallback_parent = rs_ctx->fallback_parent;
2028 fallback_signature_is_good = rs_ctx->fallback_signature_is_good;
2029
2030 /* clear saved state */
2031 rs_ctx->parent = NULL;
2032 rs_ctx->fallback_parent = NULL;
2033 rs_ctx->fallback_signature_is_good = 0;
2034
2035 /* resume where we left */
2036 goto check_signature;
2037 }
2038 #endif
2039
2040 fallback_parent = NULL;
2041 fallback_signature_is_good = 0;
2042
2043 for( parent = candidates; parent != NULL; parent = parent->next )
2044 {
2045 /* basic parenting skills (name, CA bit, key usage) */
2046 if( x509_crt_check_parent( child, parent, top ) != 0 )
2047 continue;
2048
2049 /* +1 because stored max_pathlen is 1 higher that the actual value */
2050 if( parent->max_pathlen > 0 &&
2051 (size_t) parent->max_pathlen < 1 + path_cnt - self_cnt )
2052 {
2053 continue;
2054 }
2055
2056 /* Signature */
2057 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2058 check_signature:
2059 #endif
2060 ret = x509_crt_check_signature( child, parent, rs_ctx );
2061
2062 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2063 if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
2064 {
2065 /* save state */
2066 rs_ctx->parent = parent;
2067 rs_ctx->fallback_parent = fallback_parent;
2068 rs_ctx->fallback_signature_is_good = fallback_signature_is_good;
2069
2070 return( ret );
2071 }
2072 #else
2073 (void) ret;
2074 #endif
2075
2076 signature_is_good = ret == 0;
2077 if( top && ! signature_is_good )
2078 continue;
2079
2080 /* optional time check */
2081 if( mbedtls_x509_time_is_past( &parent->valid_to ) ||
2082 mbedtls_x509_time_is_future( &parent->valid_from ) )
2083 {
2084 if( fallback_parent == NULL )
2085 {
2086 fallback_parent = parent;
2087 fallback_signature_is_good = signature_is_good;
2088 }
2089
2090 continue;
2091 }
2092
2093 break;
2094 }
2095
2096 if( parent != NULL )
2097 {
2098 *r_parent = parent;
2099 *r_signature_is_good = signature_is_good;
2100 }
2101 else
2102 {
2103 *r_parent = fallback_parent;
2104 *r_signature_is_good = fallback_signature_is_good;
2105 }
2106
2107 return( 0 );
2108 }
2109
2110 /*
2111 * Find a parent in trusted CAs or the provided chain, or return NULL.
2112 *
2113 * Searches in trusted CAs first, and return the first suitable parent found
2114 * (see find_parent_in() for definition of suitable).
2115 *
2116 * Arguments:
2117 * - [in] child: certificate for which we're looking for a parent, followed
2118 * by a chain of possible intermediates
2119 * - [in] trust_ca: list of locally trusted certificates
2120 * - [out] parent: parent found (or NULL)
2121 * - [out] parent_is_trusted: 1 if returned `parent` is trusted, or 0
2122 * - [out] signature_is_good: 1 if child signature by parent is valid, or 0
2123 * - [in] path_cnt: number of links in the chain so far (EE -> ... -> child)
2124 * - [in] self_cnt: number of self-signed certs in the chain so far
2125 * (will always be no greater than path_cnt)
2126 * - [in-out] rs_ctx: context for restarting operations
2127 *
2128 * Return value:
2129 * - 0 on success
2130 * - MBEDTLS_ERR_ECP_IN_PROGRESS otherwise
2131 */
x509_crt_find_parent(mbedtls_x509_crt * child,mbedtls_x509_crt * trust_ca,mbedtls_x509_crt ** parent,int * parent_is_trusted,int * signature_is_good,unsigned path_cnt,unsigned self_cnt,mbedtls_x509_crt_restart_ctx * rs_ctx)2132 static int x509_crt_find_parent(
2133 mbedtls_x509_crt *child,
2134 mbedtls_x509_crt *trust_ca,
2135 mbedtls_x509_crt **parent,
2136 int *parent_is_trusted,
2137 int *signature_is_good,
2138 unsigned path_cnt,
2139 unsigned self_cnt,
2140 mbedtls_x509_crt_restart_ctx *rs_ctx )
2141 {
2142 int ret;
2143 mbedtls_x509_crt *search_list;
2144
2145 *parent_is_trusted = 1;
2146
2147 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2148 /* restore then clear saved state if we have some stored */
2149 if( rs_ctx != NULL && rs_ctx->parent_is_trusted != -1 )
2150 {
2151 *parent_is_trusted = rs_ctx->parent_is_trusted;
2152 rs_ctx->parent_is_trusted = -1;
2153 }
2154 #endif
2155
2156 while( 1 ) {
2157 search_list = *parent_is_trusted ? trust_ca : child->next;
2158
2159 ret = x509_crt_find_parent_in( child, search_list,
2160 parent, signature_is_good,
2161 *parent_is_trusted,
2162 path_cnt, self_cnt, rs_ctx );
2163
2164 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2165 if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
2166 {
2167 /* save state */
2168 rs_ctx->parent_is_trusted = *parent_is_trusted;
2169 return( ret );
2170 }
2171 #else
2172 (void) ret;
2173 #endif
2174
2175 /* stop here if found or already in second iteration */
2176 if( *parent != NULL || *parent_is_trusted == 0 )
2177 break;
2178
2179 /* prepare second iteration */
2180 *parent_is_trusted = 0;
2181 }
2182
2183 /* extra precaution against mistakes in the caller */
2184 if( *parent == NULL )
2185 {
2186 *parent_is_trusted = 0;
2187 *signature_is_good = 0;
2188 }
2189
2190 return( 0 );
2191 }
2192
2193 /*
2194 * Check if an end-entity certificate is locally trusted
2195 *
2196 * Currently we require such certificates to be self-signed (actually only
2197 * check for self-issued as self-signatures are not checked)
2198 */
x509_crt_check_ee_locally_trusted(mbedtls_x509_crt * crt,mbedtls_x509_crt * trust_ca)2199 static int x509_crt_check_ee_locally_trusted(
2200 mbedtls_x509_crt *crt,
2201 mbedtls_x509_crt *trust_ca )
2202 {
2203 mbedtls_x509_crt *cur;
2204
2205 /* must be self-issued */
2206 if( x509_name_cmp( &crt->issuer, &crt->subject ) != 0 )
2207 return( -1 );
2208
2209 /* look for an exact match with trusted cert */
2210 for( cur = trust_ca; cur != NULL; cur = cur->next )
2211 {
2212 if( crt->raw.len == cur->raw.len &&
2213 memcmp( crt->raw.p, cur->raw.p, crt->raw.len ) == 0 )
2214 {
2215 return( 0 );
2216 }
2217 }
2218
2219 /* too bad */
2220 return( -1 );
2221 }
2222
2223 /*
2224 * Build and verify a certificate chain
2225 *
2226 * Given a peer-provided list of certificates EE, C1, ..., Cn and
2227 * a list of trusted certs R1, ... Rp, try to build and verify a chain
2228 * EE, Ci1, ... Ciq [, Rj]
2229 * such that every cert in the chain is a child of the next one,
2230 * jumping to a trusted root as early as possible.
2231 *
2232 * Verify that chain and return it with flags for all issues found.
2233 *
2234 * Special cases:
2235 * - EE == Rj -> return a one-element list containing it
2236 * - EE, Ci1, ..., Ciq cannot be continued with a trusted root
2237 * -> return that chain with NOT_TRUSTED set on Ciq
2238 *
2239 * Tests for (aspects of) this function should include at least:
2240 * - trusted EE
2241 * - EE -> trusted root
2242 * - EE -> intermedate CA -> trusted root
2243 * - if relevant: EE untrusted
2244 * - if relevant: EE -> intermediate, untrusted
2245 * with the aspect under test checked at each relevant level (EE, int, root).
2246 * For some aspects longer chains are required, but usually length 2 is
2247 * enough (but length 1 is not in general).
2248 *
2249 * Arguments:
2250 * - [in] crt: the cert list EE, C1, ..., Cn
2251 * - [in] trust_ca: the trusted list R1, ..., Rp
2252 * - [in] ca_crl, profile: as in verify_with_profile()
2253 * - [out] ver_chain: the built and verified chain
2254 * Only valid when return value is 0, may contain garbage otherwise!
2255 * Restart note: need not be the same when calling again to resume.
2256 * - [in-out] rs_ctx: context for restarting operations
2257 *
2258 * Return value:
2259 * - non-zero if the chain could not be fully built and examined
2260 * - 0 is the chain was successfully built and examined,
2261 * even if it was found to be invalid
2262 */
x509_crt_verify_chain(mbedtls_x509_crt * crt,mbedtls_x509_crt * trust_ca,mbedtls_x509_crl * ca_crl,const mbedtls_x509_crt_profile * profile,mbedtls_x509_crt_verify_chain * ver_chain,mbedtls_x509_crt_restart_ctx * rs_ctx)2263 static int x509_crt_verify_chain(
2264 mbedtls_x509_crt *crt,
2265 mbedtls_x509_crt *trust_ca,
2266 mbedtls_x509_crl *ca_crl,
2267 const mbedtls_x509_crt_profile *profile,
2268 mbedtls_x509_crt_verify_chain *ver_chain,
2269 mbedtls_x509_crt_restart_ctx *rs_ctx )
2270 {
2271 /* Don't initialize any of those variables here, so that the compiler can
2272 * catch potential issues with jumping ahead when restarting */
2273 int ret;
2274 uint32_t *flags;
2275 mbedtls_x509_crt_verify_chain_item *cur;
2276 mbedtls_x509_crt *child;
2277 mbedtls_x509_crt *parent;
2278 int parent_is_trusted;
2279 int child_is_trusted;
2280 int signature_is_good;
2281 unsigned self_cnt;
2282
2283 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2284 /* resume if we had an operation in progress */
2285 if( rs_ctx != NULL && rs_ctx->in_progress == x509_crt_rs_find_parent )
2286 {
2287 /* restore saved state */
2288 *ver_chain = rs_ctx->ver_chain; /* struct copy */
2289 self_cnt = rs_ctx->self_cnt;
2290
2291 /* restore derived state */
2292 cur = &ver_chain->items[ver_chain->len - 1];
2293 child = cur->crt;
2294 flags = &cur->flags;
2295
2296 goto find_parent;
2297 }
2298 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
2299
2300 child = crt;
2301 self_cnt = 0;
2302 parent_is_trusted = 0;
2303 child_is_trusted = 0;
2304
2305 while( 1 ) {
2306 /* Add certificate to the verification chain */
2307 cur = &ver_chain->items[ver_chain->len];
2308 cur->crt = child;
2309 cur->flags = 0;
2310 ver_chain->len++;
2311 flags = &cur->flags;
2312
2313 /* Check time-validity (all certificates) */
2314 if( mbedtls_x509_time_is_past( &child->valid_to ) )
2315 *flags |= MBEDTLS_X509_BADCERT_EXPIRED;
2316
2317 if( mbedtls_x509_time_is_future( &child->valid_from ) )
2318 *flags |= MBEDTLS_X509_BADCERT_FUTURE;
2319
2320 /* Stop here for trusted roots (but not for trusted EE certs) */
2321 if( child_is_trusted )
2322 return( 0 );
2323
2324 /* Check signature algorithm: MD & PK algs */
2325 if( x509_profile_check_md_alg( profile, child->sig_md ) != 0 )
2326 *flags |= MBEDTLS_X509_BADCERT_BAD_MD;
2327
2328 if( x509_profile_check_pk_alg( profile, child->sig_pk ) != 0 )
2329 *flags |= MBEDTLS_X509_BADCERT_BAD_PK;
2330
2331 /* Special case: EE certs that are locally trusted */
2332 if( ver_chain->len == 1 &&
2333 x509_crt_check_ee_locally_trusted( child, trust_ca ) == 0 )
2334 {
2335 return( 0 );
2336 }
2337
2338 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2339 find_parent:
2340 #endif
2341 /* Look for a parent in trusted CAs or up the chain */
2342 ret = x509_crt_find_parent( child, trust_ca, &parent,
2343 &parent_is_trusted, &signature_is_good,
2344 ver_chain->len - 1, self_cnt, rs_ctx );
2345
2346 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2347 if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
2348 {
2349 /* save state */
2350 rs_ctx->in_progress = x509_crt_rs_find_parent;
2351 rs_ctx->self_cnt = self_cnt;
2352 rs_ctx->ver_chain = *ver_chain; /* struct copy */
2353
2354 return( ret );
2355 }
2356 #else
2357 (void) ret;
2358 #endif
2359
2360 /* No parent? We're done here */
2361 if( parent == NULL )
2362 {
2363 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
2364 return( 0 );
2365 }
2366
2367 /* Count intermediate self-issued (not necessarily self-signed) certs.
2368 * These can occur with some strategies for key rollover, see [SIRO],
2369 * and should be excluded from max_pathlen checks. */
2370 if( ver_chain->len != 1 &&
2371 x509_name_cmp( &child->issuer, &child->subject ) == 0 )
2372 {
2373 self_cnt++;
2374 }
2375
2376 /* path_cnt is 0 for the first intermediate CA,
2377 * and if parent is trusted it's not an intermediate CA */
2378 if( ! parent_is_trusted &&
2379 ver_chain->len > MBEDTLS_X509_MAX_INTERMEDIATE_CA )
2380 {
2381 /* return immediately to avoid overflow the chain array */
2382 return( MBEDTLS_ERR_X509_FATAL_ERROR );
2383 }
2384
2385 /* signature was checked while searching parent */
2386 if( ! signature_is_good )
2387 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
2388
2389 /* check size of signing key */
2390 if( x509_profile_check_key( profile, &parent->pk ) != 0 )
2391 *flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
2392
2393 #if defined(MBEDTLS_X509_CRL_PARSE_C)
2394 /* Check trusted CA's CRL for the given crt */
2395 *flags |= x509_crt_verifycrl( child, parent, ca_crl, profile );
2396 #else
2397 (void) ca_crl;
2398 #endif
2399
2400 /* prepare for next iteration */
2401 child = parent;
2402 parent = NULL;
2403 child_is_trusted = parent_is_trusted;
2404 signature_is_good = 0;
2405 }
2406 }
2407
2408 /*
2409 * Check for CN match
2410 */
x509_crt_check_cn(const mbedtls_x509_buf * name,const char * cn,size_t cn_len)2411 static int x509_crt_check_cn( const mbedtls_x509_buf *name,
2412 const char *cn, size_t cn_len )
2413 {
2414 /* try exact match */
2415 if( name->len == cn_len &&
2416 x509_memcasecmp( cn, name->p, cn_len ) == 0 )
2417 {
2418 return( 0 );
2419 }
2420
2421 /* try wildcard match */
2422 if( x509_check_wildcard( cn, name ) == 0 )
2423 {
2424 return( 0 );
2425 }
2426
2427 return( -1 );
2428 }
2429
2430 /*
2431 * Verify the requested CN - only call this if cn is not NULL!
2432 */
x509_crt_verify_name(const mbedtls_x509_crt * crt,const char * cn,uint32_t * flags)2433 static void x509_crt_verify_name( const mbedtls_x509_crt *crt,
2434 const char *cn,
2435 uint32_t *flags )
2436 {
2437 const mbedtls_x509_name *name;
2438 const mbedtls_x509_sequence *cur;
2439 size_t cn_len = strlen( cn );
2440
2441 if( crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME )
2442 {
2443 for( cur = &crt->subject_alt_names; cur != NULL; cur = cur->next )
2444 {
2445 if( x509_crt_check_cn( &cur->buf, cn, cn_len ) == 0 )
2446 break;
2447 }
2448
2449 if( cur == NULL )
2450 *flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH;
2451 }
2452 else
2453 {
2454 for( name = &crt->subject; name != NULL; name = name->next )
2455 {
2456 if( MBEDTLS_OID_CMP( MBEDTLS_OID_AT_CN, &name->oid ) == 0 &&
2457 x509_crt_check_cn( &name->val, cn, cn_len ) == 0 )
2458 {
2459 break;
2460 }
2461 }
2462
2463 if( name == NULL )
2464 *flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH;
2465 }
2466 }
2467
2468 /*
2469 * Merge the flags for all certs in the chain, after calling callback
2470 */
x509_crt_merge_flags_with_cb(uint32_t * flags,const mbedtls_x509_crt_verify_chain * ver_chain,int (* f_vrfy)(void *,mbedtls_x509_crt *,int,uint32_t *),void * p_vrfy)2471 static int x509_crt_merge_flags_with_cb(
2472 uint32_t *flags,
2473 const mbedtls_x509_crt_verify_chain *ver_chain,
2474 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2475 void *p_vrfy )
2476 {
2477 int ret;
2478 unsigned i;
2479 uint32_t cur_flags;
2480 const mbedtls_x509_crt_verify_chain_item *cur;
2481
2482 for( i = ver_chain->len; i != 0; --i )
2483 {
2484 cur = &ver_chain->items[i-1];
2485 cur_flags = cur->flags;
2486
2487 if( NULL != f_vrfy )
2488 if( ( ret = f_vrfy( p_vrfy, cur->crt, (int) i-1, &cur_flags ) ) != 0 )
2489 return( ret );
2490
2491 *flags |= cur_flags;
2492 }
2493
2494 return( 0 );
2495 }
2496
2497 /*
2498 * Verify the certificate validity (default profile, not restartable)
2499 */
mbedtls_x509_crt_verify(mbedtls_x509_crt * crt,mbedtls_x509_crt * trust_ca,mbedtls_x509_crl * ca_crl,const char * cn,uint32_t * flags,int (* f_vrfy)(void *,mbedtls_x509_crt *,int,uint32_t *),void * p_vrfy)2500 int mbedtls_x509_crt_verify( mbedtls_x509_crt *crt,
2501 mbedtls_x509_crt *trust_ca,
2502 mbedtls_x509_crl *ca_crl,
2503 const char *cn, uint32_t *flags,
2504 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2505 void *p_vrfy )
2506 {
2507 return( mbedtls_x509_crt_verify_restartable( crt, trust_ca, ca_crl,
2508 &mbedtls_x509_crt_profile_default, cn, flags,
2509 f_vrfy, p_vrfy, NULL ) );
2510 }
2511
2512 /*
2513 * Verify the certificate validity (user-chosen profile, not restartable)
2514 */
mbedtls_x509_crt_verify_with_profile(mbedtls_x509_crt * crt,mbedtls_x509_crt * trust_ca,mbedtls_x509_crl * ca_crl,const mbedtls_x509_crt_profile * profile,const char * cn,uint32_t * flags,int (* f_vrfy)(void *,mbedtls_x509_crt *,int,uint32_t *),void * p_vrfy)2515 int mbedtls_x509_crt_verify_with_profile( mbedtls_x509_crt *crt,
2516 mbedtls_x509_crt *trust_ca,
2517 mbedtls_x509_crl *ca_crl,
2518 const mbedtls_x509_crt_profile *profile,
2519 const char *cn, uint32_t *flags,
2520 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2521 void *p_vrfy )
2522 {
2523 return( mbedtls_x509_crt_verify_restartable( crt, trust_ca, ca_crl,
2524 profile, cn, flags, f_vrfy, p_vrfy, NULL ) );
2525 }
2526
2527 /*
2528 * Verify the certificate validity, with profile, restartable version
2529 *
2530 * This function:
2531 * - checks the requested CN (if any)
2532 * - checks the type and size of the EE cert's key,
2533 * as that isn't done as part of chain building/verification currently
2534 * - builds and verifies the chain
2535 * - then calls the callback and merges the flags
2536 */
mbedtls_x509_crt_verify_restartable(mbedtls_x509_crt * crt,mbedtls_x509_crt * trust_ca,mbedtls_x509_crl * ca_crl,const mbedtls_x509_crt_profile * profile,const char * cn,uint32_t * flags,int (* f_vrfy)(void *,mbedtls_x509_crt *,int,uint32_t *),void * p_vrfy,mbedtls_x509_crt_restart_ctx * rs_ctx)2537 int mbedtls_x509_crt_verify_restartable( mbedtls_x509_crt *crt,
2538 mbedtls_x509_crt *trust_ca,
2539 mbedtls_x509_crl *ca_crl,
2540 const mbedtls_x509_crt_profile *profile,
2541 const char *cn, uint32_t *flags,
2542 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2543 void *p_vrfy,
2544 mbedtls_x509_crt_restart_ctx *rs_ctx )
2545 {
2546 int ret;
2547 mbedtls_pk_type_t pk_type;
2548 mbedtls_x509_crt_verify_chain ver_chain;
2549 uint32_t ee_flags;
2550
2551 *flags = 0;
2552 ee_flags = 0;
2553 x509_crt_verify_chain_reset( &ver_chain );
2554
2555 if( profile == NULL )
2556 {
2557 ret = MBEDTLS_ERR_X509_BAD_INPUT_DATA;
2558 goto exit;
2559 }
2560
2561 /* check name if requested */
2562 if( cn != NULL )
2563 x509_crt_verify_name( crt, cn, &ee_flags );
2564
2565 /* Check the type and size of the key */
2566 pk_type = mbedtls_pk_get_type( &crt->pk );
2567
2568 if( x509_profile_check_pk_alg( profile, pk_type ) != 0 )
2569 ee_flags |= MBEDTLS_X509_BADCERT_BAD_PK;
2570
2571 if( x509_profile_check_key( profile, &crt->pk ) != 0 )
2572 ee_flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
2573
2574 /* Check the chain */
2575 ret = x509_crt_verify_chain( crt, trust_ca, ca_crl, profile,
2576 &ver_chain, rs_ctx );
2577
2578 if( ret != 0 )
2579 goto exit;
2580
2581 /* Merge end-entity flags */
2582 ver_chain.items[0].flags |= ee_flags;
2583
2584 /* Build final flags, calling callback on the way if any */
2585 ret = x509_crt_merge_flags_with_cb( flags, &ver_chain, f_vrfy, p_vrfy );
2586
2587 exit:
2588 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2589 if( rs_ctx != NULL && ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
2590 mbedtls_x509_crt_restart_free( rs_ctx );
2591 #endif
2592
2593 /* prevent misuse of the vrfy callback - VERIFY_FAILED would be ignored by
2594 * the SSL module for authmode optional, but non-zero return from the
2595 * callback means a fatal error so it shouldn't be ignored */
2596 if( ret == MBEDTLS_ERR_X509_CERT_VERIFY_FAILED )
2597 ret = MBEDTLS_ERR_X509_FATAL_ERROR;
2598
2599 if( ret != 0 )
2600 {
2601 *flags = (uint32_t) -1;
2602 return( ret );
2603 }
2604
2605 if( *flags != 0 )
2606 return( MBEDTLS_ERR_X509_CERT_VERIFY_FAILED );
2607
2608 return( 0 );
2609 }
2610
2611 /*
2612 * Initialize a certificate chain
2613 */
mbedtls_x509_crt_init(mbedtls_x509_crt * crt)2614 void mbedtls_x509_crt_init( mbedtls_x509_crt *crt )
2615 {
2616 memset( crt, 0, sizeof(mbedtls_x509_crt) );
2617 }
2618
2619 /*
2620 * Unallocate all certificate data
2621 */
mbedtls_x509_crt_free(mbedtls_x509_crt * crt)2622 void mbedtls_x509_crt_free( mbedtls_x509_crt *crt )
2623 {
2624 mbedtls_x509_crt *cert_cur = crt;
2625 mbedtls_x509_crt *cert_prv;
2626 mbedtls_x509_name *name_cur;
2627 mbedtls_x509_name *name_prv;
2628 mbedtls_x509_sequence *seq_cur;
2629 mbedtls_x509_sequence *seq_prv;
2630
2631 if( crt == NULL )
2632 return;
2633
2634 do
2635 {
2636 mbedtls_pk_free( &cert_cur->pk );
2637
2638 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
2639 mbedtls_free( cert_cur->sig_opts );
2640 #endif
2641
2642 name_cur = cert_cur->issuer.next;
2643 while( name_cur != NULL )
2644 {
2645 name_prv = name_cur;
2646 name_cur = name_cur->next;
2647 mbedtls_platform_zeroize( name_prv, sizeof( mbedtls_x509_name ) );
2648 mbedtls_free( name_prv );
2649 }
2650
2651 name_cur = cert_cur->subject.next;
2652 while( name_cur != NULL )
2653 {
2654 name_prv = name_cur;
2655 name_cur = name_cur->next;
2656 mbedtls_platform_zeroize( name_prv, sizeof( mbedtls_x509_name ) );
2657 mbedtls_free( name_prv );
2658 }
2659
2660 seq_cur = cert_cur->ext_key_usage.next;
2661 while( seq_cur != NULL )
2662 {
2663 seq_prv = seq_cur;
2664 seq_cur = seq_cur->next;
2665 mbedtls_platform_zeroize( seq_prv,
2666 sizeof( mbedtls_x509_sequence ) );
2667 mbedtls_free( seq_prv );
2668 }
2669
2670 seq_cur = cert_cur->subject_alt_names.next;
2671 while( seq_cur != NULL )
2672 {
2673 seq_prv = seq_cur;
2674 seq_cur = seq_cur->next;
2675 mbedtls_platform_zeroize( seq_prv,
2676 sizeof( mbedtls_x509_sequence ) );
2677 mbedtls_free( seq_prv );
2678 }
2679
2680 if( cert_cur->raw.p != NULL )
2681 {
2682 mbedtls_platform_zeroize( cert_cur->raw.p, cert_cur->raw.len );
2683 mbedtls_free( cert_cur->raw.p );
2684 }
2685
2686 cert_cur = cert_cur->next;
2687 }
2688 while( cert_cur != NULL );
2689
2690 cert_cur = crt;
2691 do
2692 {
2693 cert_prv = cert_cur;
2694 cert_cur = cert_cur->next;
2695
2696 mbedtls_platform_zeroize( cert_prv, sizeof( mbedtls_x509_crt ) );
2697 if( cert_prv != crt )
2698 mbedtls_free( cert_prv );
2699 }
2700 while( cert_cur != NULL );
2701 }
2702
2703 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2704 /*
2705 * Initialize a restart context
2706 */
mbedtls_x509_crt_restart_init(mbedtls_x509_crt_restart_ctx * ctx)2707 void mbedtls_x509_crt_restart_init( mbedtls_x509_crt_restart_ctx *ctx )
2708 {
2709 mbedtls_pk_restart_init( &ctx->pk );
2710
2711 ctx->parent = NULL;
2712 ctx->fallback_parent = NULL;
2713 ctx->fallback_signature_is_good = 0;
2714
2715 ctx->parent_is_trusted = -1;
2716
2717 ctx->in_progress = x509_crt_rs_none;
2718 ctx->self_cnt = 0;
2719 x509_crt_verify_chain_reset( &ctx->ver_chain );
2720 }
2721
2722 /*
2723 * Free the components of a restart context
2724 */
mbedtls_x509_crt_restart_free(mbedtls_x509_crt_restart_ctx * ctx)2725 void mbedtls_x509_crt_restart_free( mbedtls_x509_crt_restart_ctx *ctx )
2726 {
2727 if( ctx == NULL )
2728 return;
2729
2730 mbedtls_pk_restart_free( &ctx->pk );
2731 mbedtls_x509_crt_restart_init( ctx );
2732 }
2733 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
2734
2735 #endif /* MBEDTLS_X509_CRT_PARSE_C */
2736