1 /*
2 * X.509 certificate parsing and verification
3 *
4 * Copyright The Mbed TLS Contributors
5 * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
6 *
7 * This file is provided under the Apache License 2.0, or the
8 * GNU General Public License v2.0 or later.
9 *
10 * **********
11 * Apache License 2.0:
12 *
13 * Licensed under the Apache License, Version 2.0 (the "License"); you may
14 * not use this file except in compliance with the License.
15 * You may obtain a copy of the License at
16 *
17 * http://www.apache.org/licenses/LICENSE-2.0
18 *
19 * Unless required by applicable law or agreed to in writing, software
20 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
21 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
22 * See the License for the specific language governing permissions and
23 * limitations under the License.
24 *
25 * **********
26 *
27 * **********
28 * GNU General Public License v2.0 or later:
29 *
30 * This program is free software; you can redistribute it and/or modify
31 * it under the terms of the GNU General Public License as published by
32 * the Free Software Foundation; either version 2 of the License, or
33 * (at your option) any later version.
34 *
35 * This program is distributed in the hope that it will be useful,
36 * but WITHOUT ANY WARRANTY; without even the implied warranty of
37 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
38 * GNU General Public License for more details.
39 *
40 * You should have received a copy of the GNU General Public License along
41 * with this program; if not, write to the Free Software Foundation, Inc.,
42 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
43 *
44 * **********
45 */
46 /*
47 * The ITU-T X.509 standard defines a certificate format for PKI.
48 *
49 * http://www.ietf.org/rfc/rfc5280.txt (Certificates and CRLs)
50 * http://www.ietf.org/rfc/rfc3279.txt (Alg IDs for CRLs)
51 * http://www.ietf.org/rfc/rfc2986.txt (CSRs, aka PKCS#10)
52 *
53 * http://www.itu.int/ITU-T/studygroups/com17/languages/X.680-0207.pdf
54 * http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf
55 *
56 * [SIRO] https://cabforum.org/wp-content/uploads/Chunghwatelecom201503cabforumV4.pdf
57 */
58
59 #if !defined(MBEDTLS_CONFIG_FILE)
60 #include "mbedtls/config.h"
61 #else
62 #include MBEDTLS_CONFIG_FILE
63 #endif
64
65 #if defined(MBEDTLS_X509_CRT_PARSE_C)
66
67 #include "mbedtls/x509_crt.h"
68 #include "mbedtls/oid.h"
69 #include "mbedtls/platform_util.h"
70
71 #include <string.h>
72
73 #if defined(MBEDTLS_PEM_PARSE_C)
74 #include "mbedtls/pem.h"
75 #endif
76
77 #if defined(MBEDTLS_PLATFORM_C)
78 #include "mbedtls/platform.h"
79 #else
80 #include <stdio.h>
81 #include <stdlib.h>
82 #define mbedtls_free free
83 #define mbedtls_calloc calloc
84 #define mbedtls_snprintf snprintf
85 #endif
86
87 #if defined(MBEDTLS_THREADING_C)
88 #include "mbedtls/threading.h"
89 #endif
90
91 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
92 #include <windows.h>
93 #else
94 #include <time.h>
95 #endif
96
97 #if defined(MBEDTLS_FS_IO)
98 #include <stdio.h>
99 #if !defined(_WIN32) || defined(EFIX64) || defined(EFI32)
100 #include <sys/types.h>
101 #include <sys/stat.h>
102 #include <dirent.h>
103 #endif /* !_WIN32 || EFIX64 || EFI32 */
104 #endif
105
106 /*
107 * Item in a verification chain: cert and flags for it
108 */
109 typedef struct {
110 mbedtls_x509_crt *crt;
111 uint32_t flags;
112 } x509_crt_verify_chain_item;
113
114 /*
115 * Max size of verification chain: end-entity + intermediates + trusted root
116 */
117 #define X509_MAX_VERIFY_CHAIN_SIZE ( MBEDTLS_X509_MAX_INTERMEDIATE_CA + 2 )
118
119 /* Default profile. Do not remove items unless there are serious security
120 * concerns. */
121 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_default =
122 {
123 #if defined(MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_CERTIFICATES)
124 /* Allow SHA-1 (weak, but still safe in controlled environments) */
125 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA1 ) |
126 #endif
127 /* Only SHA-2 hashes */
128 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA224 ) |
129 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
130 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ) |
131 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA512 ),
132 0xFFFFFFF, /* Any PK alg */
133 0xFFFFFFF, /* Any curve */
134 2048,
135 };
136
137 /*
138 * Next-default profile
139 */
140 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_next =
141 {
142 /* Hashes from SHA-256 and above */
143 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
144 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ) |
145 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA512 ),
146 0xFFFFFFF, /* Any PK alg */
147 #if defined(MBEDTLS_ECP_C)
148 /* Curves at or above 128-bit security level */
149 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256R1 ) |
150 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP384R1 ) |
151 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP521R1 ) |
152 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP256R1 ) |
153 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP384R1 ) |
154 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP512R1 ) |
155 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256K1 ),
156 #else
157 0,
158 #endif
159 2048,
160 };
161
162 /*
163 * NSA Suite B Profile
164 */
165 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_suiteb =
166 {
167 /* Only SHA-256 and 384 */
168 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
169 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ),
170 /* Only ECDSA */
171 MBEDTLS_X509_ID_FLAG( MBEDTLS_PK_ECDSA ) |
172 MBEDTLS_X509_ID_FLAG( MBEDTLS_PK_ECKEY ),
173 #if defined(MBEDTLS_ECP_C)
174 /* Only NIST P-256 and P-384 */
175 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256R1 ) |
176 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP384R1 ),
177 #else
178 0,
179 #endif
180 0,
181 };
182
183 /*
184 * Check md_alg against profile
185 * Return 0 if md_alg is acceptable for this profile, -1 otherwise
186 */
x509_profile_check_md_alg(const mbedtls_x509_crt_profile * profile,mbedtls_md_type_t md_alg)187 static int x509_profile_check_md_alg( const mbedtls_x509_crt_profile *profile,
188 mbedtls_md_type_t md_alg )
189 {
190 if( md_alg == MBEDTLS_MD_NONE )
191 return( -1 );
192
193 if( ( profile->allowed_mds & MBEDTLS_X509_ID_FLAG( md_alg ) ) != 0 )
194 return( 0 );
195
196 return( -1 );
197 }
198
199 /*
200 * Check pk_alg against profile
201 * Return 0 if pk_alg is acceptable for this profile, -1 otherwise
202 */
x509_profile_check_pk_alg(const mbedtls_x509_crt_profile * profile,mbedtls_pk_type_t pk_alg)203 static int x509_profile_check_pk_alg( const mbedtls_x509_crt_profile *profile,
204 mbedtls_pk_type_t pk_alg )
205 {
206 if( pk_alg == MBEDTLS_PK_NONE )
207 return( -1 );
208
209 if( ( profile->allowed_pks & MBEDTLS_X509_ID_FLAG( pk_alg ) ) != 0 )
210 return( 0 );
211
212 return( -1 );
213 }
214
215 /*
216 * Check key against profile
217 * Return 0 if pk is acceptable for this profile, -1 otherwise
218 */
x509_profile_check_key(const mbedtls_x509_crt_profile * profile,const mbedtls_pk_context * pk)219 static int x509_profile_check_key( const mbedtls_x509_crt_profile *profile,
220 const mbedtls_pk_context *pk )
221 {
222 const mbedtls_pk_type_t pk_alg = mbedtls_pk_get_type( pk );
223
224 #if defined(MBEDTLS_RSA_C)
225 if( pk_alg == MBEDTLS_PK_RSA || pk_alg == MBEDTLS_PK_RSASSA_PSS )
226 {
227 if( mbedtls_pk_get_bitlen( pk ) >= profile->rsa_min_bitlen )
228 return( 0 );
229
230 return( -1 );
231 }
232 #endif
233
234 #if defined(MBEDTLS_ECP_C)
235 if( pk_alg == MBEDTLS_PK_ECDSA ||
236 pk_alg == MBEDTLS_PK_ECKEY ||
237 pk_alg == MBEDTLS_PK_ECKEY_DH )
238 {
239 const mbedtls_ecp_group_id gid = mbedtls_pk_ec( *pk )->grp.id;
240
241 if( gid == MBEDTLS_ECP_DP_NONE )
242 return( -1 );
243
244 if( ( profile->allowed_curves & MBEDTLS_X509_ID_FLAG( gid ) ) != 0 )
245 return( 0 );
246
247 return( -1 );
248 }
249 #endif
250
251 return( -1 );
252 }
253
254 /*
255 * Like memcmp, but case-insensitive and always returns -1 if different
256 */
x509_memcasecmp(const void * s1,const void * s2,size_t len)257 static int x509_memcasecmp( const void *s1, const void *s2, size_t len )
258 {
259 size_t i;
260 unsigned char diff;
261 const unsigned char *n1 = s1, *n2 = s2;
262
263 for( i = 0; i < len; i++ )
264 {
265 diff = n1[i] ^ n2[i];
266
267 if( diff == 0 )
268 continue;
269
270 if( diff == 32 &&
271 ( ( n1[i] >= 'a' && n1[i] <= 'z' ) ||
272 ( n1[i] >= 'A' && n1[i] <= 'Z' ) ) )
273 {
274 continue;
275 }
276
277 return( -1 );
278 }
279
280 return( 0 );
281 }
282
283 /*
284 * Return 0 if name matches wildcard, -1 otherwise
285 */
x509_check_wildcard(const char * cn,const mbedtls_x509_buf * name)286 static int x509_check_wildcard( const char *cn, const mbedtls_x509_buf *name )
287 {
288 size_t i;
289 size_t cn_idx = 0, cn_len = strlen( cn );
290
291 /* We can't have a match if there is no wildcard to match */
292 if( name->len < 3 || name->p[0] != '*' || name->p[1] != '.' )
293 return( -1 );
294
295 for( i = 0; i < cn_len; ++i )
296 {
297 if( cn[i] == '.' )
298 {
299 cn_idx = i;
300 break;
301 }
302 }
303
304 if( cn_idx == 0 )
305 return( -1 );
306
307 if( cn_len - cn_idx == name->len - 1 &&
308 x509_memcasecmp( name->p + 1, cn + cn_idx, name->len - 1 ) == 0 )
309 {
310 return( 0 );
311 }
312
313 return( -1 );
314 }
315
316 /*
317 * Compare two X.509 strings, case-insensitive, and allowing for some encoding
318 * variations (but not all).
319 *
320 * Return 0 if equal, -1 otherwise.
321 */
x509_string_cmp(const mbedtls_x509_buf * a,const mbedtls_x509_buf * b)322 static int x509_string_cmp( const mbedtls_x509_buf *a, const mbedtls_x509_buf *b )
323 {
324 if( a->tag == b->tag &&
325 a->len == b->len &&
326 memcmp( a->p, b->p, b->len ) == 0 )
327 {
328 return( 0 );
329 }
330
331 if( ( a->tag == MBEDTLS_ASN1_UTF8_STRING || a->tag == MBEDTLS_ASN1_PRINTABLE_STRING ) &&
332 ( b->tag == MBEDTLS_ASN1_UTF8_STRING || b->tag == MBEDTLS_ASN1_PRINTABLE_STRING ) &&
333 a->len == b->len &&
334 x509_memcasecmp( a->p, b->p, b->len ) == 0 )
335 {
336 return( 0 );
337 }
338
339 return( -1 );
340 }
341
342 /*
343 * Compare two X.509 Names (aka rdnSequence).
344 *
345 * See RFC 5280 section 7.1, though we don't implement the whole algorithm:
346 * we sometimes return unequal when the full algorithm would return equal,
347 * but never the other way. (In particular, we don't do Unicode normalisation
348 * or space folding.)
349 *
350 * Return 0 if equal, -1 otherwise.
351 */
x509_name_cmp(const mbedtls_x509_name * a,const mbedtls_x509_name * b)352 static int x509_name_cmp( const mbedtls_x509_name *a, const mbedtls_x509_name *b )
353 {
354 /* Avoid recursion, it might not be optimised by the compiler */
355 while( a != NULL || b != NULL )
356 {
357 if( a == NULL || b == NULL )
358 return( -1 );
359
360 /* type */
361 if( a->oid.tag != b->oid.tag ||
362 a->oid.len != b->oid.len ||
363 memcmp( a->oid.p, b->oid.p, b->oid.len ) != 0 )
364 {
365 return( -1 );
366 }
367
368 /* value */
369 if( x509_string_cmp( &a->val, &b->val ) != 0 )
370 return( -1 );
371
372 /* structure of the list of sets */
373 if( a->next_merged != b->next_merged )
374 return( -1 );
375
376 a = a->next;
377 b = b->next;
378 }
379
380 /* a == NULL == b */
381 return( 0 );
382 }
383
384 /*
385 * Reset (init or clear) a verify_chain
386 */
x509_crt_verify_chain_reset(mbedtls_x509_crt_verify_chain * ver_chain)387 static void x509_crt_verify_chain_reset(
388 mbedtls_x509_crt_verify_chain *ver_chain )
389 {
390 size_t i;
391
392 for( i = 0; i < MBEDTLS_X509_MAX_VERIFY_CHAIN_SIZE; i++ )
393 {
394 ver_chain->items[i].crt = NULL;
395 ver_chain->items[i].flags = (uint32_t) -1;
396 }
397
398 ver_chain->len = 0;
399 }
400
401 /*
402 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
403 */
x509_get_version(unsigned char ** p,const unsigned char * end,int * ver)404 static int x509_get_version( unsigned char **p,
405 const unsigned char *end,
406 int *ver )
407 {
408 int ret;
409 size_t len;
410
411 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
412 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 0 ) ) != 0 )
413 {
414 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
415 {
416 *ver = 0;
417 return( 0 );
418 }
419
420 return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
421 }
422
423 end = *p + len;
424
425 if( ( ret = mbedtls_asn1_get_int( p, end, ver ) ) != 0 )
426 return( MBEDTLS_ERR_X509_INVALID_VERSION + ret );
427
428 if( *p != end )
429 return( MBEDTLS_ERR_X509_INVALID_VERSION +
430 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
431
432 return( 0 );
433 }
434
435 /*
436 * Validity ::= SEQUENCE {
437 * notBefore Time,
438 * notAfter Time }
439 */
x509_get_dates(unsigned char ** p,const unsigned char * end,mbedtls_x509_time * from,mbedtls_x509_time * to)440 static int x509_get_dates( unsigned char **p,
441 const unsigned char *end,
442 mbedtls_x509_time *from,
443 mbedtls_x509_time *to )
444 {
445 int ret;
446 size_t len;
447
448 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
449 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
450 return( MBEDTLS_ERR_X509_INVALID_DATE + ret );
451
452 end = *p + len;
453
454 if( ( ret = mbedtls_x509_get_time( p, end, from ) ) != 0 )
455 return( ret );
456
457 if( ( ret = mbedtls_x509_get_time( p, end, to ) ) != 0 )
458 return( ret );
459
460 if( *p != end )
461 return( MBEDTLS_ERR_X509_INVALID_DATE +
462 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
463
464 return( 0 );
465 }
466
467 /*
468 * X.509 v2/v3 unique identifier (not parsed)
469 */
x509_get_uid(unsigned char ** p,const unsigned char * end,mbedtls_x509_buf * uid,int n)470 static int x509_get_uid( unsigned char **p,
471 const unsigned char *end,
472 mbedtls_x509_buf *uid, int n )
473 {
474 int ret;
475
476 if( *p == end )
477 return( 0 );
478
479 uid->tag = **p;
480
481 if( ( ret = mbedtls_asn1_get_tag( p, end, &uid->len,
482 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | n ) ) != 0 )
483 {
484 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
485 return( 0 );
486
487 return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
488 }
489
490 uid->p = *p;
491 *p += uid->len;
492
493 return( 0 );
494 }
495
x509_get_basic_constraints(unsigned char ** p,const unsigned char * end,int * ca_istrue,int * max_pathlen)496 static int x509_get_basic_constraints( unsigned char **p,
497 const unsigned char *end,
498 int *ca_istrue,
499 int *max_pathlen )
500 {
501 int ret;
502 size_t len;
503
504 /*
505 * BasicConstraints ::= SEQUENCE {
506 * cA BOOLEAN DEFAULT FALSE,
507 * pathLenConstraint INTEGER (0..MAX) OPTIONAL }
508 */
509 *ca_istrue = 0; /* DEFAULT FALSE */
510 *max_pathlen = 0; /* endless */
511
512 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
513 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
514 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
515
516 if( *p == end )
517 return( 0 );
518
519 if( ( ret = mbedtls_asn1_get_bool( p, end, ca_istrue ) ) != 0 )
520 {
521 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
522 ret = mbedtls_asn1_get_int( p, end, ca_istrue );
523
524 if( ret != 0 )
525 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
526
527 if( *ca_istrue != 0 )
528 *ca_istrue = 1;
529 }
530
531 if( *p == end )
532 return( 0 );
533
534 if( ( ret = mbedtls_asn1_get_int( p, end, max_pathlen ) ) != 0 )
535 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
536
537 if( *p != end )
538 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
539 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
540
541 /* Do not accept max_pathlen equal to INT_MAX to avoid a signed integer
542 * overflow, which is an undefined behavior. */
543 if( *max_pathlen == INT_MAX )
544 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
545 MBEDTLS_ERR_ASN1_INVALID_LENGTH );
546
547 (*max_pathlen)++;
548
549 return( 0 );
550 }
551
x509_get_ns_cert_type(unsigned char ** p,const unsigned char * end,unsigned char * ns_cert_type)552 static int x509_get_ns_cert_type( unsigned char **p,
553 const unsigned char *end,
554 unsigned char *ns_cert_type)
555 {
556 int ret;
557 mbedtls_x509_bitstring bs = { 0, 0, NULL };
558
559 if( ( ret = mbedtls_asn1_get_bitstring( p, end, &bs ) ) != 0 )
560 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
561
562 if( bs.len != 1 )
563 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
564 MBEDTLS_ERR_ASN1_INVALID_LENGTH );
565
566 /* Get actual bitstring */
567 *ns_cert_type = *bs.p;
568 return( 0 );
569 }
570
x509_get_key_usage(unsigned char ** p,const unsigned char * end,unsigned int * key_usage)571 static int x509_get_key_usage( unsigned char **p,
572 const unsigned char *end,
573 unsigned int *key_usage)
574 {
575 int ret;
576 size_t i;
577 mbedtls_x509_bitstring bs = { 0, 0, NULL };
578
579 if( ( ret = mbedtls_asn1_get_bitstring( p, end, &bs ) ) != 0 )
580 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
581
582 if( bs.len < 1 )
583 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
584 MBEDTLS_ERR_ASN1_INVALID_LENGTH );
585
586 /* Get actual bitstring */
587 *key_usage = 0;
588 for( i = 0; i < bs.len && i < sizeof( unsigned int ); i++ )
589 {
590 *key_usage |= (unsigned int) bs.p[i] << (8*i);
591 }
592
593 return( 0 );
594 }
595
596 /*
597 * ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId
598 *
599 * KeyPurposeId ::= OBJECT IDENTIFIER
600 */
x509_get_ext_key_usage(unsigned char ** p,const unsigned char * end,mbedtls_x509_sequence * ext_key_usage)601 static int x509_get_ext_key_usage( unsigned char **p,
602 const unsigned char *end,
603 mbedtls_x509_sequence *ext_key_usage)
604 {
605 int ret;
606
607 if( ( ret = mbedtls_asn1_get_sequence_of( p, end, ext_key_usage, MBEDTLS_ASN1_OID ) ) != 0 )
608 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
609
610 /* Sequence length must be >= 1 */
611 if( ext_key_usage->buf.p == NULL )
612 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
613 MBEDTLS_ERR_ASN1_INVALID_LENGTH );
614
615 return( 0 );
616 }
617
618 /*
619 * SubjectAltName ::= GeneralNames
620 *
621 * GeneralNames ::= SEQUENCE SIZE (1..MAX) OF GeneralName
622 *
623 * GeneralName ::= CHOICE {
624 * otherName [0] OtherName,
625 * rfc822Name [1] IA5String,
626 * dNSName [2] IA5String,
627 * x400Address [3] ORAddress,
628 * directoryName [4] Name,
629 * ediPartyName [5] EDIPartyName,
630 * uniformResourceIdentifier [6] IA5String,
631 * iPAddress [7] OCTET STRING,
632 * registeredID [8] OBJECT IDENTIFIER }
633 *
634 * OtherName ::= SEQUENCE {
635 * type-id OBJECT IDENTIFIER,
636 * value [0] EXPLICIT ANY DEFINED BY type-id }
637 *
638 * EDIPartyName ::= SEQUENCE {
639 * nameAssigner [0] DirectoryString OPTIONAL,
640 * partyName [1] DirectoryString }
641 *
642 * NOTE: we only parse and use dNSName at this point.
643 */
x509_get_subject_alt_name(unsigned char ** p,const unsigned char * end,mbedtls_x509_sequence * subject_alt_name)644 static int x509_get_subject_alt_name( unsigned char **p,
645 const unsigned char *end,
646 mbedtls_x509_sequence *subject_alt_name )
647 {
648 int ret;
649 size_t len, tag_len;
650 mbedtls_asn1_buf *buf;
651 unsigned char tag;
652 mbedtls_asn1_sequence *cur = subject_alt_name;
653
654 /* Get main sequence tag */
655 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
656 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
657 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
658
659 if( *p + len != end )
660 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
661 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
662
663 while( *p < end )
664 {
665 if( ( end - *p ) < 1 )
666 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
667 MBEDTLS_ERR_ASN1_OUT_OF_DATA );
668
669 tag = **p;
670 (*p)++;
671 if( ( ret = mbedtls_asn1_get_len( p, end, &tag_len ) ) != 0 )
672 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
673
674 if( ( tag & MBEDTLS_ASN1_TAG_CLASS_MASK ) !=
675 MBEDTLS_ASN1_CONTEXT_SPECIFIC )
676 {
677 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
678 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
679 }
680
681 /* Skip everything but DNS name */
682 if( tag != ( MBEDTLS_ASN1_CONTEXT_SPECIFIC | 2 ) )
683 {
684 *p += tag_len;
685 continue;
686 }
687
688 /* Allocate and assign next pointer */
689 if( cur->buf.p != NULL )
690 {
691 if( cur->next != NULL )
692 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS );
693
694 cur->next = mbedtls_calloc( 1, sizeof( mbedtls_asn1_sequence ) );
695
696 if( cur->next == NULL )
697 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
698 MBEDTLS_ERR_ASN1_ALLOC_FAILED );
699
700 cur = cur->next;
701 }
702
703 buf = &(cur->buf);
704 buf->tag = tag;
705 buf->p = *p;
706 buf->len = tag_len;
707 *p += buf->len;
708 }
709
710 /* Set final sequence entry's next pointer to NULL */
711 cur->next = NULL;
712
713 if( *p != end )
714 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
715 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
716
717 return( 0 );
718 }
719
720 /*
721 * X.509 v3 extensions
722 *
723 */
x509_get_crt_ext(unsigned char ** p,const unsigned char * end,mbedtls_x509_crt * crt)724 static int x509_get_crt_ext( unsigned char **p,
725 const unsigned char *end,
726 mbedtls_x509_crt *crt )
727 {
728 int ret;
729 size_t len;
730 unsigned char *end_ext_data, *end_ext_octet;
731
732 if( *p == end )
733 return( 0 );
734
735 if( ( ret = mbedtls_x509_get_ext( p, end, &crt->v3_ext, 3 ) ) != 0 )
736 return( ret );
737
738 end = crt->v3_ext.p + crt->v3_ext.len;
739 while( *p < end )
740 {
741 /*
742 * Extension ::= SEQUENCE {
743 * extnID OBJECT IDENTIFIER,
744 * critical BOOLEAN DEFAULT FALSE,
745 * extnValue OCTET STRING }
746 */
747 mbedtls_x509_buf extn_oid = {0, 0, NULL};
748 int is_critical = 0; /* DEFAULT FALSE */
749 int ext_type = 0;
750
751 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
752 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
753 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
754
755 end_ext_data = *p + len;
756
757 /* Get extension ID */
758 if( ( ret = mbedtls_asn1_get_tag( p, end_ext_data, &extn_oid.len,
759 MBEDTLS_ASN1_OID ) ) != 0 )
760 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
761
762 extn_oid.tag = MBEDTLS_ASN1_OID;
763 extn_oid.p = *p;
764 *p += extn_oid.len;
765
766 /* Get optional critical */
767 if( ( ret = mbedtls_asn1_get_bool( p, end_ext_data, &is_critical ) ) != 0 &&
768 ( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) )
769 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
770
771 /* Data should be octet string type */
772 if( ( ret = mbedtls_asn1_get_tag( p, end_ext_data, &len,
773 MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
774 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
775
776 end_ext_octet = *p + len;
777
778 if( end_ext_octet != end_ext_data )
779 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
780 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
781
782 /*
783 * Detect supported extensions
784 */
785 ret = mbedtls_oid_get_x509_ext_type( &extn_oid, &ext_type );
786
787 if( ret != 0 )
788 {
789 /* No parser found, skip extension */
790 *p = end_ext_octet;
791
792 #if !defined(MBEDTLS_X509_ALLOW_UNSUPPORTED_CRITICAL_EXTENSION)
793 if( is_critical )
794 {
795 /* Data is marked as critical: fail */
796 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
797 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
798 }
799 #endif
800 continue;
801 }
802
803 /* Forbid repeated extensions */
804 if( ( crt->ext_types & ext_type ) != 0 )
805 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS );
806
807 crt->ext_types |= ext_type;
808
809 switch( ext_type )
810 {
811 case MBEDTLS_X509_EXT_BASIC_CONSTRAINTS:
812 /* Parse basic constraints */
813 if( ( ret = x509_get_basic_constraints( p, end_ext_octet,
814 &crt->ca_istrue, &crt->max_pathlen ) ) != 0 )
815 return( ret );
816 break;
817
818 case MBEDTLS_X509_EXT_KEY_USAGE:
819 /* Parse key usage */
820 if( ( ret = x509_get_key_usage( p, end_ext_octet,
821 &crt->key_usage ) ) != 0 )
822 return( ret );
823 break;
824
825 case MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE:
826 /* Parse extended key usage */
827 if( ( ret = x509_get_ext_key_usage( p, end_ext_octet,
828 &crt->ext_key_usage ) ) != 0 )
829 return( ret );
830 break;
831
832 case MBEDTLS_X509_EXT_SUBJECT_ALT_NAME:
833 /* Parse subject alt name */
834 if( ( ret = x509_get_subject_alt_name( p, end_ext_octet,
835 &crt->subject_alt_names ) ) != 0 )
836 return( ret );
837 break;
838
839 case MBEDTLS_X509_EXT_NS_CERT_TYPE:
840 /* Parse netscape certificate type */
841 if( ( ret = x509_get_ns_cert_type( p, end_ext_octet,
842 &crt->ns_cert_type ) ) != 0 )
843 return( ret );
844 break;
845
846 default:
847 return( MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE );
848 }
849 }
850
851 if( *p != end )
852 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
853 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
854
855 return( 0 );
856 }
857
858 /*
859 * Parse and fill a single X.509 certificate in DER format
860 */
x509_crt_parse_der_core(mbedtls_x509_crt * crt,const unsigned char * buf,size_t buflen)861 static int x509_crt_parse_der_core( mbedtls_x509_crt *crt, const unsigned char *buf,
862 size_t buflen )
863 {
864 int ret;
865 size_t len;
866 unsigned char *p, *end, *crt_end;
867 mbedtls_x509_buf sig_params1, sig_params2, sig_oid2;
868
869 memset( &sig_params1, 0, sizeof( mbedtls_x509_buf ) );
870 memset( &sig_params2, 0, sizeof( mbedtls_x509_buf ) );
871 memset( &sig_oid2, 0, sizeof( mbedtls_x509_buf ) );
872
873 /*
874 * Check for valid input
875 */
876 if( crt == NULL || buf == NULL )
877 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
878
879 // Use the original buffer until we figure out actual length
880 p = (unsigned char*) buf;
881 len = buflen;
882 end = p + len;
883
884 /*
885 * Certificate ::= SEQUENCE {
886 * tbsCertificate TBSCertificate,
887 * signatureAlgorithm AlgorithmIdentifier,
888 * signatureValue BIT STRING }
889 */
890 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
891 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
892 {
893 mbedtls_x509_crt_free( crt );
894 return( MBEDTLS_ERR_X509_INVALID_FORMAT );
895 }
896
897 if( len > (size_t) ( end - p ) )
898 {
899 mbedtls_x509_crt_free( crt );
900 return( MBEDTLS_ERR_X509_INVALID_FORMAT +
901 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
902 }
903 crt_end = p + len;
904
905 // Create and populate a new buffer for the raw field
906 crt->raw.len = crt_end - buf;
907 crt->raw.p = p = mbedtls_calloc( 1, crt->raw.len );
908 if( p == NULL )
909 return( MBEDTLS_ERR_X509_ALLOC_FAILED );
910
911 memcpy( p, buf, crt->raw.len );
912
913 // Direct pointers to the new buffer
914 p += crt->raw.len - len;
915 end = crt_end = p + len;
916
917 /*
918 * TBSCertificate ::= SEQUENCE {
919 */
920 crt->tbs.p = p;
921
922 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
923 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
924 {
925 mbedtls_x509_crt_free( crt );
926 return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
927 }
928
929 end = p + len;
930 crt->tbs.len = end - crt->tbs.p;
931
932 /*
933 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
934 *
935 * CertificateSerialNumber ::= INTEGER
936 *
937 * signature AlgorithmIdentifier
938 */
939 if( ( ret = x509_get_version( &p, end, &crt->version ) ) != 0 ||
940 ( ret = mbedtls_x509_get_serial( &p, end, &crt->serial ) ) != 0 ||
941 ( ret = mbedtls_x509_get_alg( &p, end, &crt->sig_oid,
942 &sig_params1 ) ) != 0 )
943 {
944 mbedtls_x509_crt_free( crt );
945 return( ret );
946 }
947
948 if( crt->version < 0 || crt->version > 2 )
949 {
950 mbedtls_x509_crt_free( crt );
951 return( MBEDTLS_ERR_X509_UNKNOWN_VERSION );
952 }
953
954 crt->version++;
955
956 if( ( ret = mbedtls_x509_get_sig_alg( &crt->sig_oid, &sig_params1,
957 &crt->sig_md, &crt->sig_pk,
958 &crt->sig_opts ) ) != 0 )
959 {
960 mbedtls_x509_crt_free( crt );
961 return( ret );
962 }
963
964 /*
965 * issuer Name
966 */
967 crt->issuer_raw.p = p;
968
969 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
970 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
971 {
972 mbedtls_x509_crt_free( crt );
973 return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
974 }
975
976 if( ( ret = mbedtls_x509_get_name( &p, p + len, &crt->issuer ) ) != 0 )
977 {
978 mbedtls_x509_crt_free( crt );
979 return( ret );
980 }
981
982 crt->issuer_raw.len = p - crt->issuer_raw.p;
983
984 /*
985 * Validity ::= SEQUENCE {
986 * notBefore Time,
987 * notAfter Time }
988 *
989 */
990 if( ( ret = x509_get_dates( &p, end, &crt->valid_from,
991 &crt->valid_to ) ) != 0 )
992 {
993 mbedtls_x509_crt_free( crt );
994 return( ret );
995 }
996
997 /*
998 * subject Name
999 */
1000 crt->subject_raw.p = p;
1001
1002 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
1003 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
1004 {
1005 mbedtls_x509_crt_free( crt );
1006 return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
1007 }
1008
1009 if( len && ( ret = mbedtls_x509_get_name( &p, p + len, &crt->subject ) ) != 0 )
1010 {
1011 mbedtls_x509_crt_free( crt );
1012 return( ret );
1013 }
1014
1015 crt->subject_raw.len = p - crt->subject_raw.p;
1016
1017 /*
1018 * SubjectPublicKeyInfo
1019 */
1020 if( ( ret = mbedtls_pk_parse_subpubkey( &p, end, &crt->pk ) ) != 0 )
1021 {
1022 mbedtls_x509_crt_free( crt );
1023 return( ret );
1024 }
1025
1026 /*
1027 * issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
1028 * -- If present, version shall be v2 or v3
1029 * subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
1030 * -- If present, version shall be v2 or v3
1031 * extensions [3] EXPLICIT Extensions OPTIONAL
1032 * -- If present, version shall be v3
1033 */
1034 if( crt->version == 2 || crt->version == 3 )
1035 {
1036 ret = x509_get_uid( &p, end, &crt->issuer_id, 1 );
1037 if( ret != 0 )
1038 {
1039 mbedtls_x509_crt_free( crt );
1040 return( ret );
1041 }
1042 }
1043
1044 if( crt->version == 2 || crt->version == 3 )
1045 {
1046 ret = x509_get_uid( &p, end, &crt->subject_id, 2 );
1047 if( ret != 0 )
1048 {
1049 mbedtls_x509_crt_free( crt );
1050 return( ret );
1051 }
1052 }
1053
1054 #if !defined(MBEDTLS_X509_ALLOW_EXTENSIONS_NON_V3)
1055 if( crt->version == 3 )
1056 #endif
1057 {
1058 ret = x509_get_crt_ext( &p, end, crt );
1059 if( ret != 0 )
1060 {
1061 mbedtls_x509_crt_free( crt );
1062 return( ret );
1063 }
1064 }
1065
1066 if( p != end )
1067 {
1068 mbedtls_x509_crt_free( crt );
1069 return( MBEDTLS_ERR_X509_INVALID_FORMAT +
1070 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
1071 }
1072
1073 end = crt_end;
1074
1075 /*
1076 * }
1077 * -- end of TBSCertificate
1078 *
1079 * signatureAlgorithm AlgorithmIdentifier,
1080 * signatureValue BIT STRING
1081 */
1082 if( ( ret = mbedtls_x509_get_alg( &p, end, &sig_oid2, &sig_params2 ) ) != 0 )
1083 {
1084 mbedtls_x509_crt_free( crt );
1085 return( ret );
1086 }
1087
1088 if( crt->sig_oid.len != sig_oid2.len ||
1089 memcmp( crt->sig_oid.p, sig_oid2.p, crt->sig_oid.len ) != 0 ||
1090 sig_params1.tag != sig_params2.tag ||
1091 sig_params1.len != sig_params2.len ||
1092 ( sig_params1.len != 0 &&
1093 memcmp( sig_params1.p, sig_params2.p, sig_params1.len ) != 0 ) )
1094 {
1095 mbedtls_x509_crt_free( crt );
1096 return( MBEDTLS_ERR_X509_SIG_MISMATCH );
1097 }
1098
1099 if( ( ret = mbedtls_x509_get_sig( &p, end, &crt->sig ) ) != 0 )
1100 {
1101 mbedtls_x509_crt_free( crt );
1102 return( ret );
1103 }
1104
1105 if( p != end )
1106 {
1107 mbedtls_x509_crt_free( crt );
1108 return( MBEDTLS_ERR_X509_INVALID_FORMAT +
1109 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
1110 }
1111
1112 return( 0 );
1113 }
1114
1115 /*
1116 * Parse one X.509 certificate in DER format from a buffer and add them to a
1117 * chained list
1118 */
mbedtls_x509_crt_parse_der(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)1119 int mbedtls_x509_crt_parse_der( mbedtls_x509_crt *chain, const unsigned char *buf,
1120 size_t buflen )
1121 {
1122 int ret;
1123 mbedtls_x509_crt *crt = chain, *prev = NULL;
1124
1125 /*
1126 * Check for valid input
1127 */
1128 if( crt == NULL || buf == NULL )
1129 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1130
1131 while( crt->version != 0 && crt->next != NULL )
1132 {
1133 prev = crt;
1134 crt = crt->next;
1135 }
1136
1137 /*
1138 * Add new certificate on the end of the chain if needed.
1139 */
1140 if( crt->version != 0 && crt->next == NULL )
1141 {
1142 crt->next = mbedtls_calloc( 1, sizeof( mbedtls_x509_crt ) );
1143
1144 if( crt->next == NULL )
1145 return( MBEDTLS_ERR_X509_ALLOC_FAILED );
1146
1147 prev = crt;
1148 mbedtls_x509_crt_init( crt->next );
1149 crt = crt->next;
1150 }
1151
1152 if( ( ret = x509_crt_parse_der_core( crt, buf, buflen ) ) != 0 )
1153 {
1154 if( prev )
1155 prev->next = NULL;
1156
1157 if( crt != chain )
1158 mbedtls_free( crt );
1159
1160 return( ret );
1161 }
1162
1163 return( 0 );
1164 }
1165
1166 /*
1167 * Parse one or more PEM certificates from a buffer and add them to the chained
1168 * list
1169 */
mbedtls_x509_crt_parse(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)1170 int mbedtls_x509_crt_parse( mbedtls_x509_crt *chain, const unsigned char *buf, size_t buflen )
1171 {
1172 #if defined(MBEDTLS_PEM_PARSE_C)
1173 int success = 0, first_error = 0, total_failed = 0;
1174 int buf_format = MBEDTLS_X509_FORMAT_DER;
1175 #endif
1176
1177 /*
1178 * Check for valid input
1179 */
1180 if( chain == NULL || buf == NULL )
1181 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1182
1183 /*
1184 * Determine buffer content. Buffer contains either one DER certificate or
1185 * one or more PEM certificates.
1186 */
1187 #if defined(MBEDTLS_PEM_PARSE_C)
1188 if( buflen != 0 && buf[buflen - 1] == '\0' &&
1189 strstr( (const char *) buf, "-----BEGIN CERTIFICATE-----" ) != NULL )
1190 {
1191 buf_format = MBEDTLS_X509_FORMAT_PEM;
1192 }
1193
1194 if( buf_format == MBEDTLS_X509_FORMAT_DER )
1195 return mbedtls_x509_crt_parse_der( chain, buf, buflen );
1196 #else
1197 return mbedtls_x509_crt_parse_der( chain, buf, buflen );
1198 #endif
1199
1200 #if defined(MBEDTLS_PEM_PARSE_C)
1201 if( buf_format == MBEDTLS_X509_FORMAT_PEM )
1202 {
1203 int ret;
1204 mbedtls_pem_context pem;
1205
1206 /* 1 rather than 0 since the terminating NULL byte is counted in */
1207 while( buflen > 1 )
1208 {
1209 size_t use_len;
1210 mbedtls_pem_init( &pem );
1211
1212 /* If we get there, we know the string is null-terminated */
1213 ret = mbedtls_pem_read_buffer( &pem,
1214 "-----BEGIN CERTIFICATE-----",
1215 "-----END CERTIFICATE-----",
1216 buf, NULL, 0, &use_len );
1217
1218 if( ret == 0 )
1219 {
1220 /*
1221 * Was PEM encoded
1222 */
1223 buflen -= use_len;
1224 buf += use_len;
1225 }
1226 else if( ret == MBEDTLS_ERR_PEM_BAD_INPUT_DATA )
1227 {
1228 return( ret );
1229 }
1230 else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
1231 {
1232 mbedtls_pem_free( &pem );
1233
1234 /*
1235 * PEM header and footer were found
1236 */
1237 buflen -= use_len;
1238 buf += use_len;
1239
1240 if( first_error == 0 )
1241 first_error = ret;
1242
1243 total_failed++;
1244 continue;
1245 }
1246 else
1247 break;
1248
1249 ret = mbedtls_x509_crt_parse_der( chain, pem.buf, pem.buflen );
1250
1251 mbedtls_pem_free( &pem );
1252
1253 if( ret != 0 )
1254 {
1255 /*
1256 * Quit parsing on a memory error
1257 */
1258 if( ret == MBEDTLS_ERR_X509_ALLOC_FAILED )
1259 return( ret );
1260
1261 if( first_error == 0 )
1262 first_error = ret;
1263
1264 total_failed++;
1265 continue;
1266 }
1267
1268 success = 1;
1269 }
1270 }
1271
1272 if( success )
1273 return( total_failed );
1274 else if( first_error )
1275 return( first_error );
1276 else
1277 return( MBEDTLS_ERR_X509_CERT_UNKNOWN_FORMAT );
1278 #endif /* MBEDTLS_PEM_PARSE_C */
1279 }
1280
1281 #if defined(MBEDTLS_FS_IO)
1282 /*
1283 * Load one or more certificates and add them to the chained list
1284 */
mbedtls_x509_crt_parse_file(mbedtls_x509_crt * chain,const char * path)1285 int mbedtls_x509_crt_parse_file( mbedtls_x509_crt *chain, const char *path )
1286 {
1287 int ret;
1288 size_t n;
1289 unsigned char *buf;
1290
1291 if( ( ret = mbedtls_pk_load_file( path, &buf, &n ) ) != 0 )
1292 return( ret );
1293
1294 ret = mbedtls_x509_crt_parse( chain, buf, n );
1295
1296 mbedtls_platform_zeroize( buf, n );
1297 mbedtls_free( buf );
1298
1299 return( ret );
1300 }
1301
mbedtls_x509_crt_parse_path(mbedtls_x509_crt * chain,const char * path)1302 int mbedtls_x509_crt_parse_path( mbedtls_x509_crt *chain, const char *path )
1303 {
1304 int ret = 0;
1305 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
1306 int w_ret;
1307 WCHAR szDir[MAX_PATH];
1308 char filename[MAX_PATH];
1309 char *p;
1310 size_t len = strlen( path );
1311
1312 WIN32_FIND_DATAW file_data;
1313 HANDLE hFind;
1314
1315 if( len > MAX_PATH - 3 )
1316 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1317
1318 memset( szDir, 0, sizeof(szDir) );
1319 memset( filename, 0, MAX_PATH );
1320 memcpy( filename, path, len );
1321 filename[len++] = '\\';
1322 p = filename + len;
1323 filename[len++] = '*';
1324
1325 w_ret = MultiByteToWideChar( CP_ACP, 0, filename, (int)len, szDir,
1326 MAX_PATH - 3 );
1327 if( w_ret == 0 )
1328 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1329
1330 hFind = FindFirstFileW( szDir, &file_data );
1331 if( hFind == INVALID_HANDLE_VALUE )
1332 return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
1333
1334 len = MAX_PATH - len;
1335 do
1336 {
1337 memset( p, 0, len );
1338
1339 if( file_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY )
1340 continue;
1341
1342 w_ret = WideCharToMultiByte( CP_ACP, 0, file_data.cFileName,
1343 lstrlenW( file_data.cFileName ),
1344 p, (int) len - 1,
1345 NULL, NULL );
1346 if( w_ret == 0 )
1347 {
1348 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1349 goto cleanup;
1350 }
1351
1352 w_ret = mbedtls_x509_crt_parse_file( chain, filename );
1353 if( w_ret < 0 )
1354 ret++;
1355 else
1356 ret += w_ret;
1357 }
1358 while( FindNextFileW( hFind, &file_data ) != 0 );
1359
1360 if( GetLastError() != ERROR_NO_MORE_FILES )
1361 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1362
1363 cleanup:
1364 FindClose( hFind );
1365 #else /* _WIN32 */
1366 int t_ret;
1367 int snp_ret;
1368 struct stat sb;
1369 struct dirent *entry;
1370 char entry_name[MBEDTLS_X509_MAX_FILE_PATH_LEN];
1371 DIR *dir = opendir( path );
1372
1373 if( dir == NULL )
1374 return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
1375
1376 #if defined(MBEDTLS_THREADING_C)
1377 if( ( ret = mbedtls_mutex_lock( &mbedtls_threading_readdir_mutex ) ) != 0 )
1378 {
1379 closedir( dir );
1380 return( ret );
1381 }
1382 #endif /* MBEDTLS_THREADING_C */
1383
1384 while( ( entry = readdir( dir ) ) != NULL )
1385 {
1386 snp_ret = mbedtls_snprintf( entry_name, sizeof entry_name,
1387 "%s/%s", path, entry->d_name );
1388
1389 if( snp_ret < 0 || (size_t)snp_ret >= sizeof entry_name )
1390 {
1391 ret = MBEDTLS_ERR_X509_BUFFER_TOO_SMALL;
1392 goto cleanup;
1393 }
1394 else if( stat( entry_name, &sb ) == -1 )
1395 {
1396 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1397 goto cleanup;
1398 }
1399
1400 if( !S_ISREG( sb.st_mode ) )
1401 continue;
1402
1403 // Ignore parse errors
1404 //
1405 t_ret = mbedtls_x509_crt_parse_file( chain, entry_name );
1406 if( t_ret < 0 )
1407 ret++;
1408 else
1409 ret += t_ret;
1410 }
1411
1412 cleanup:
1413 closedir( dir );
1414
1415 #if defined(MBEDTLS_THREADING_C)
1416 if( mbedtls_mutex_unlock( &mbedtls_threading_readdir_mutex ) != 0 )
1417 ret = MBEDTLS_ERR_THREADING_MUTEX_ERROR;
1418 #endif /* MBEDTLS_THREADING_C */
1419
1420 #endif /* _WIN32 */
1421
1422 return( ret );
1423 }
1424 #endif /* MBEDTLS_FS_IO */
1425
x509_info_subject_alt_name(char ** buf,size_t * size,const mbedtls_x509_sequence * subject_alt_name)1426 static int x509_info_subject_alt_name( char **buf, size_t *size,
1427 const mbedtls_x509_sequence *subject_alt_name )
1428 {
1429 size_t i;
1430 size_t n = *size;
1431 char *p = *buf;
1432 const mbedtls_x509_sequence *cur = subject_alt_name;
1433 const char *sep = "";
1434 size_t sep_len = 0;
1435
1436 while( cur != NULL )
1437 {
1438 if( cur->buf.len + sep_len >= n )
1439 {
1440 *p = '\0';
1441 return( MBEDTLS_ERR_X509_BUFFER_TOO_SMALL );
1442 }
1443
1444 n -= cur->buf.len + sep_len;
1445 for( i = 0; i < sep_len; i++ )
1446 *p++ = sep[i];
1447 for( i = 0; i < cur->buf.len; i++ )
1448 *p++ = cur->buf.p[i];
1449
1450 sep = ", ";
1451 sep_len = 2;
1452
1453 cur = cur->next;
1454 }
1455
1456 *p = '\0';
1457
1458 *size = n;
1459 *buf = p;
1460
1461 return( 0 );
1462 }
1463
1464 #define PRINT_ITEM(i) \
1465 { \
1466 ret = mbedtls_snprintf( p, n, "%s" i, sep ); \
1467 MBEDTLS_X509_SAFE_SNPRINTF; \
1468 sep = ", "; \
1469 }
1470
1471 #define CERT_TYPE(type,name) \
1472 if( ns_cert_type & (type) ) \
1473 PRINT_ITEM( name );
1474
x509_info_cert_type(char ** buf,size_t * size,unsigned char ns_cert_type)1475 static int x509_info_cert_type( char **buf, size_t *size,
1476 unsigned char ns_cert_type )
1477 {
1478 int ret;
1479 size_t n = *size;
1480 char *p = *buf;
1481 const char *sep = "";
1482
1483 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_CLIENT, "SSL Client" );
1484 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER, "SSL Server" );
1485 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_EMAIL, "Email" );
1486 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING, "Object Signing" );
1487 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_RESERVED, "Reserved" );
1488 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_CA, "SSL CA" );
1489 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_EMAIL_CA, "Email CA" );
1490 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING_CA, "Object Signing CA" );
1491
1492 *size = n;
1493 *buf = p;
1494
1495 return( 0 );
1496 }
1497
1498 #define KEY_USAGE(code,name) \
1499 if( key_usage & (code) ) \
1500 PRINT_ITEM( name );
1501
x509_info_key_usage(char ** buf,size_t * size,unsigned int key_usage)1502 static int x509_info_key_usage( char **buf, size_t *size,
1503 unsigned int key_usage )
1504 {
1505 int ret;
1506 size_t n = *size;
1507 char *p = *buf;
1508 const char *sep = "";
1509
1510 KEY_USAGE( MBEDTLS_X509_KU_DIGITAL_SIGNATURE, "Digital Signature" );
1511 KEY_USAGE( MBEDTLS_X509_KU_NON_REPUDIATION, "Non Repudiation" );
1512 KEY_USAGE( MBEDTLS_X509_KU_KEY_ENCIPHERMENT, "Key Encipherment" );
1513 KEY_USAGE( MBEDTLS_X509_KU_DATA_ENCIPHERMENT, "Data Encipherment" );
1514 KEY_USAGE( MBEDTLS_X509_KU_KEY_AGREEMENT, "Key Agreement" );
1515 KEY_USAGE( MBEDTLS_X509_KU_KEY_CERT_SIGN, "Key Cert Sign" );
1516 KEY_USAGE( MBEDTLS_X509_KU_CRL_SIGN, "CRL Sign" );
1517 KEY_USAGE( MBEDTLS_X509_KU_ENCIPHER_ONLY, "Encipher Only" );
1518 KEY_USAGE( MBEDTLS_X509_KU_DECIPHER_ONLY, "Decipher Only" );
1519
1520 *size = n;
1521 *buf = p;
1522
1523 return( 0 );
1524 }
1525
x509_info_ext_key_usage(char ** buf,size_t * size,const mbedtls_x509_sequence * extended_key_usage)1526 static int x509_info_ext_key_usage( char **buf, size_t *size,
1527 const mbedtls_x509_sequence *extended_key_usage )
1528 {
1529 int ret;
1530 const char *desc;
1531 size_t n = *size;
1532 char *p = *buf;
1533 const mbedtls_x509_sequence *cur = extended_key_usage;
1534 const char *sep = "";
1535
1536 while( cur != NULL )
1537 {
1538 if( mbedtls_oid_get_extended_key_usage( &cur->buf, &desc ) != 0 )
1539 desc = "???";
1540
1541 ret = mbedtls_snprintf( p, n, "%s%s", sep, desc );
1542 MBEDTLS_X509_SAFE_SNPRINTF;
1543
1544 sep = ", ";
1545
1546 cur = cur->next;
1547 }
1548
1549 *size = n;
1550 *buf = p;
1551
1552 return( 0 );
1553 }
1554
1555 /*
1556 * Return an informational string about the certificate.
1557 */
1558 #define BEFORE_COLON 18
1559 #define BC "18"
mbedtls_x509_crt_info(char * buf,size_t size,const char * prefix,const mbedtls_x509_crt * crt)1560 int mbedtls_x509_crt_info( char *buf, size_t size, const char *prefix,
1561 const mbedtls_x509_crt *crt )
1562 {
1563 int ret;
1564 size_t n;
1565 char *p;
1566 char key_size_str[BEFORE_COLON];
1567
1568 p = buf;
1569 n = size;
1570
1571 if( NULL == crt )
1572 {
1573 ret = mbedtls_snprintf( p, n, "\nCertificate is uninitialised!\n" );
1574 MBEDTLS_X509_SAFE_SNPRINTF;
1575
1576 return( (int) ( size - n ) );
1577 }
1578
1579 ret = mbedtls_snprintf( p, n, "%scert. version : %d\n",
1580 prefix, crt->version );
1581 MBEDTLS_X509_SAFE_SNPRINTF;
1582 ret = mbedtls_snprintf( p, n, "%sserial number : ",
1583 prefix );
1584 MBEDTLS_X509_SAFE_SNPRINTF;
1585
1586 ret = mbedtls_x509_serial_gets( p, n, &crt->serial );
1587 MBEDTLS_X509_SAFE_SNPRINTF;
1588
1589 ret = mbedtls_snprintf( p, n, "\n%sissuer name : ", prefix );
1590 MBEDTLS_X509_SAFE_SNPRINTF;
1591 ret = mbedtls_x509_dn_gets( p, n, &crt->issuer );
1592 MBEDTLS_X509_SAFE_SNPRINTF;
1593
1594 ret = mbedtls_snprintf( p, n, "\n%ssubject name : ", prefix );
1595 MBEDTLS_X509_SAFE_SNPRINTF;
1596 ret = mbedtls_x509_dn_gets( p, n, &crt->subject );
1597 MBEDTLS_X509_SAFE_SNPRINTF;
1598
1599 ret = mbedtls_snprintf( p, n, "\n%sissued on : " \
1600 "%04d-%02d-%02d %02d:%02d:%02d", prefix,
1601 crt->valid_from.year, crt->valid_from.mon,
1602 crt->valid_from.day, crt->valid_from.hour,
1603 crt->valid_from.min, crt->valid_from.sec );
1604 MBEDTLS_X509_SAFE_SNPRINTF;
1605
1606 ret = mbedtls_snprintf( p, n, "\n%sexpires on : " \
1607 "%04d-%02d-%02d %02d:%02d:%02d", prefix,
1608 crt->valid_to.year, crt->valid_to.mon,
1609 crt->valid_to.day, crt->valid_to.hour,
1610 crt->valid_to.min, crt->valid_to.sec );
1611 MBEDTLS_X509_SAFE_SNPRINTF;
1612
1613 ret = mbedtls_snprintf( p, n, "\n%ssigned using : ", prefix );
1614 MBEDTLS_X509_SAFE_SNPRINTF;
1615
1616 ret = mbedtls_x509_sig_alg_gets( p, n, &crt->sig_oid, crt->sig_pk,
1617 crt->sig_md, crt->sig_opts );
1618 MBEDTLS_X509_SAFE_SNPRINTF;
1619
1620 /* Key size */
1621 if( ( ret = mbedtls_x509_key_size_helper( key_size_str, BEFORE_COLON,
1622 mbedtls_pk_get_name( &crt->pk ) ) ) != 0 )
1623 {
1624 return( ret );
1625 }
1626
1627 ret = mbedtls_snprintf( p, n, "\n%s%-" BC "s: %d bits", prefix, key_size_str,
1628 (int) mbedtls_pk_get_bitlen( &crt->pk ) );
1629 MBEDTLS_X509_SAFE_SNPRINTF;
1630
1631 /*
1632 * Optional extensions
1633 */
1634
1635 if( crt->ext_types & MBEDTLS_X509_EXT_BASIC_CONSTRAINTS )
1636 {
1637 ret = mbedtls_snprintf( p, n, "\n%sbasic constraints : CA=%s", prefix,
1638 crt->ca_istrue ? "true" : "false" );
1639 MBEDTLS_X509_SAFE_SNPRINTF;
1640
1641 if( crt->max_pathlen > 0 )
1642 {
1643 ret = mbedtls_snprintf( p, n, ", max_pathlen=%d", crt->max_pathlen - 1 );
1644 MBEDTLS_X509_SAFE_SNPRINTF;
1645 }
1646 }
1647
1648 if( crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME )
1649 {
1650 ret = mbedtls_snprintf( p, n, "\n%ssubject alt name : ", prefix );
1651 MBEDTLS_X509_SAFE_SNPRINTF;
1652
1653 if( ( ret = x509_info_subject_alt_name( &p, &n,
1654 &crt->subject_alt_names ) ) != 0 )
1655 return( ret );
1656 }
1657
1658 if( crt->ext_types & MBEDTLS_X509_EXT_NS_CERT_TYPE )
1659 {
1660 ret = mbedtls_snprintf( p, n, "\n%scert. type : ", prefix );
1661 MBEDTLS_X509_SAFE_SNPRINTF;
1662
1663 if( ( ret = x509_info_cert_type( &p, &n, crt->ns_cert_type ) ) != 0 )
1664 return( ret );
1665 }
1666
1667 if( crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE )
1668 {
1669 ret = mbedtls_snprintf( p, n, "\n%skey usage : ", prefix );
1670 MBEDTLS_X509_SAFE_SNPRINTF;
1671
1672 if( ( ret = x509_info_key_usage( &p, &n, crt->key_usage ) ) != 0 )
1673 return( ret );
1674 }
1675
1676 if( crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE )
1677 {
1678 ret = mbedtls_snprintf( p, n, "\n%sext key usage : ", prefix );
1679 MBEDTLS_X509_SAFE_SNPRINTF;
1680
1681 if( ( ret = x509_info_ext_key_usage( &p, &n,
1682 &crt->ext_key_usage ) ) != 0 )
1683 return( ret );
1684 }
1685
1686 ret = mbedtls_snprintf( p, n, "\n" );
1687 MBEDTLS_X509_SAFE_SNPRINTF;
1688
1689 return( (int) ( size - n ) );
1690 }
1691
1692 struct x509_crt_verify_string {
1693 int code;
1694 const char *string;
1695 };
1696
1697 static const struct x509_crt_verify_string x509_crt_verify_strings[] = {
1698 { MBEDTLS_X509_BADCERT_EXPIRED, "The certificate validity has expired" },
1699 { MBEDTLS_X509_BADCERT_REVOKED, "The certificate has been revoked (is on a CRL)" },
1700 { MBEDTLS_X509_BADCERT_CN_MISMATCH, "The certificate Common Name (CN) does not match with the expected CN" },
1701 { MBEDTLS_X509_BADCERT_NOT_TRUSTED, "The certificate is not correctly signed by the trusted CA" },
1702 { MBEDTLS_X509_BADCRL_NOT_TRUSTED, "The CRL is not correctly signed by the trusted CA" },
1703 { MBEDTLS_X509_BADCRL_EXPIRED, "The CRL is expired" },
1704 { MBEDTLS_X509_BADCERT_MISSING, "Certificate was missing" },
1705 { MBEDTLS_X509_BADCERT_SKIP_VERIFY, "Certificate verification was skipped" },
1706 { MBEDTLS_X509_BADCERT_OTHER, "Other reason (can be used by verify callback)" },
1707 { MBEDTLS_X509_BADCERT_FUTURE, "The certificate validity starts in the future" },
1708 { MBEDTLS_X509_BADCRL_FUTURE, "The CRL is from the future" },
1709 { MBEDTLS_X509_BADCERT_KEY_USAGE, "Usage does not match the keyUsage extension" },
1710 { MBEDTLS_X509_BADCERT_EXT_KEY_USAGE, "Usage does not match the extendedKeyUsage extension" },
1711 { MBEDTLS_X509_BADCERT_NS_CERT_TYPE, "Usage does not match the nsCertType extension" },
1712 { MBEDTLS_X509_BADCERT_BAD_MD, "The certificate is signed with an unacceptable hash." },
1713 { MBEDTLS_X509_BADCERT_BAD_PK, "The certificate is signed with an unacceptable PK alg (eg RSA vs ECDSA)." },
1714 { MBEDTLS_X509_BADCERT_BAD_KEY, "The certificate is signed with an unacceptable key (eg bad curve, RSA too short)." },
1715 { MBEDTLS_X509_BADCRL_BAD_MD, "The CRL is signed with an unacceptable hash." },
1716 { MBEDTLS_X509_BADCRL_BAD_PK, "The CRL is signed with an unacceptable PK alg (eg RSA vs ECDSA)." },
1717 { MBEDTLS_X509_BADCRL_BAD_KEY, "The CRL is signed with an unacceptable key (eg bad curve, RSA too short)." },
1718 { 0, NULL }
1719 };
1720
mbedtls_x509_crt_verify_info(char * buf,size_t size,const char * prefix,uint32_t flags)1721 int mbedtls_x509_crt_verify_info( char *buf, size_t size, const char *prefix,
1722 uint32_t flags )
1723 {
1724 int ret;
1725 const struct x509_crt_verify_string *cur;
1726 char *p = buf;
1727 size_t n = size;
1728
1729 for( cur = x509_crt_verify_strings; cur->string != NULL ; cur++ )
1730 {
1731 if( ( flags & cur->code ) == 0 )
1732 continue;
1733
1734 ret = mbedtls_snprintf( p, n, "%s%s\n", prefix, cur->string );
1735 MBEDTLS_X509_SAFE_SNPRINTF;
1736 flags ^= cur->code;
1737 }
1738
1739 if( flags != 0 )
1740 {
1741 ret = mbedtls_snprintf( p, n, "%sUnknown reason "
1742 "(this should not happen)\n", prefix );
1743 MBEDTLS_X509_SAFE_SNPRINTF;
1744 }
1745
1746 return( (int) ( size - n ) );
1747 }
1748
1749 #if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
mbedtls_x509_crt_check_key_usage(const mbedtls_x509_crt * crt,unsigned int usage)1750 int mbedtls_x509_crt_check_key_usage( const mbedtls_x509_crt *crt,
1751 unsigned int usage )
1752 {
1753 unsigned int usage_must, usage_may;
1754 unsigned int may_mask = MBEDTLS_X509_KU_ENCIPHER_ONLY
1755 | MBEDTLS_X509_KU_DECIPHER_ONLY;
1756
1757 if( ( crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE ) == 0 )
1758 return( 0 );
1759
1760 usage_must = usage & ~may_mask;
1761
1762 if( ( ( crt->key_usage & ~may_mask ) & usage_must ) != usage_must )
1763 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1764
1765 usage_may = usage & may_mask;
1766
1767 if( ( ( crt->key_usage & may_mask ) | usage_may ) != usage_may )
1768 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1769
1770 return( 0 );
1771 }
1772 #endif
1773
1774 #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)1775 int mbedtls_x509_crt_check_extended_key_usage( const mbedtls_x509_crt *crt,
1776 const char *usage_oid,
1777 size_t usage_len )
1778 {
1779 const mbedtls_x509_sequence *cur;
1780
1781 /* Extension is not mandatory, absent means no restriction */
1782 if( ( crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE ) == 0 )
1783 return( 0 );
1784
1785 /*
1786 * Look for the requested usage (or wildcard ANY) in our list
1787 */
1788 for( cur = &crt->ext_key_usage; cur != NULL; cur = cur->next )
1789 {
1790 const mbedtls_x509_buf *cur_oid = &cur->buf;
1791
1792 if( cur_oid->len == usage_len &&
1793 memcmp( cur_oid->p, usage_oid, usage_len ) == 0 )
1794 {
1795 return( 0 );
1796 }
1797
1798 if( MBEDTLS_OID_CMP( MBEDTLS_OID_ANY_EXTENDED_KEY_USAGE, cur_oid ) == 0 )
1799 return( 0 );
1800 }
1801
1802 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1803 }
1804 #endif /* MBEDTLS_X509_CHECK_EXTENDED_KEY_USAGE */
1805
1806 #if defined(MBEDTLS_X509_CRL_PARSE_C)
1807 /*
1808 * Return 1 if the certificate is revoked, or 0 otherwise.
1809 */
mbedtls_x509_crt_is_revoked(const mbedtls_x509_crt * crt,const mbedtls_x509_crl * crl)1810 int mbedtls_x509_crt_is_revoked( const mbedtls_x509_crt *crt, const mbedtls_x509_crl *crl )
1811 {
1812 const mbedtls_x509_crl_entry *cur = &crl->entry;
1813
1814 while( cur != NULL && cur->serial.len != 0 )
1815 {
1816 if( crt->serial.len == cur->serial.len &&
1817 memcmp( crt->serial.p, cur->serial.p, crt->serial.len ) == 0 )
1818 {
1819 return( 1 );
1820 }
1821
1822 cur = cur->next;
1823 }
1824
1825 return( 0 );
1826 }
1827
1828 /*
1829 * Check that the given certificate is not revoked according to the CRL.
1830 * Skip validation if no CRL for the given CA is present.
1831 */
x509_crt_verifycrl(mbedtls_x509_crt * crt,mbedtls_x509_crt * ca,mbedtls_x509_crl * crl_list,const mbedtls_x509_crt_profile * profile)1832 static int x509_crt_verifycrl( mbedtls_x509_crt *crt, mbedtls_x509_crt *ca,
1833 mbedtls_x509_crl *crl_list,
1834 const mbedtls_x509_crt_profile *profile )
1835 {
1836 int flags = 0;
1837 unsigned char hash[MBEDTLS_MD_MAX_SIZE];
1838 const mbedtls_md_info_t *md_info;
1839
1840 if( ca == NULL )
1841 return( flags );
1842
1843 while( crl_list != NULL )
1844 {
1845 if( crl_list->version == 0 ||
1846 x509_name_cmp( &crl_list->issuer, &ca->subject ) != 0 )
1847 {
1848 crl_list = crl_list->next;
1849 continue;
1850 }
1851
1852 /*
1853 * Check if the CA is configured to sign CRLs
1854 */
1855 #if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
1856 if( mbedtls_x509_crt_check_key_usage( ca,
1857 MBEDTLS_X509_KU_CRL_SIGN ) != 0 )
1858 {
1859 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
1860 break;
1861 }
1862 #endif
1863
1864 /*
1865 * Check if CRL is correctly signed by the trusted CA
1866 */
1867 if( x509_profile_check_md_alg( profile, crl_list->sig_md ) != 0 )
1868 flags |= MBEDTLS_X509_BADCRL_BAD_MD;
1869
1870 if( x509_profile_check_pk_alg( profile, crl_list->sig_pk ) != 0 )
1871 flags |= MBEDTLS_X509_BADCRL_BAD_PK;
1872
1873 md_info = mbedtls_md_info_from_type( crl_list->sig_md );
1874 if( mbedtls_md( md_info, crl_list->tbs.p, crl_list->tbs.len, hash ) != 0 )
1875 {
1876 /* Note: this can't happen except after an internal error */
1877 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
1878 break;
1879 }
1880
1881 if( x509_profile_check_key( profile, &ca->pk ) != 0 )
1882 flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
1883
1884 if( mbedtls_pk_verify_ext( crl_list->sig_pk, crl_list->sig_opts, &ca->pk,
1885 crl_list->sig_md, hash, mbedtls_md_get_size( md_info ),
1886 crl_list->sig.p, crl_list->sig.len ) != 0 )
1887 {
1888 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
1889 break;
1890 }
1891
1892 /*
1893 * Check for validity of CRL (Do not drop out)
1894 */
1895 if( mbedtls_x509_time_is_past( &crl_list->next_update ) )
1896 flags |= MBEDTLS_X509_BADCRL_EXPIRED;
1897
1898 if( mbedtls_x509_time_is_future( &crl_list->this_update ) )
1899 flags |= MBEDTLS_X509_BADCRL_FUTURE;
1900
1901 /*
1902 * Check if certificate is revoked
1903 */
1904 if( mbedtls_x509_crt_is_revoked( crt, crl_list ) )
1905 {
1906 flags |= MBEDTLS_X509_BADCERT_REVOKED;
1907 break;
1908 }
1909
1910 crl_list = crl_list->next;
1911 }
1912
1913 return( flags );
1914 }
1915 #endif /* MBEDTLS_X509_CRL_PARSE_C */
1916
1917 /*
1918 * Check the signature of a certificate by its parent
1919 */
x509_crt_check_signature(const mbedtls_x509_crt * child,mbedtls_x509_crt * parent,mbedtls_x509_crt_restart_ctx * rs_ctx)1920 static int x509_crt_check_signature( const mbedtls_x509_crt *child,
1921 mbedtls_x509_crt *parent,
1922 mbedtls_x509_crt_restart_ctx *rs_ctx )
1923 {
1924 const mbedtls_md_info_t *md_info;
1925 unsigned char hash[MBEDTLS_MD_MAX_SIZE];
1926
1927 md_info = mbedtls_md_info_from_type( child->sig_md );
1928 if( mbedtls_md( md_info, child->tbs.p, child->tbs.len, hash ) != 0 )
1929 {
1930 /* Note: this can't happen except after an internal error */
1931 return( -1 );
1932 }
1933
1934 /* Skip expensive computation on obvious mismatch */
1935 if( ! mbedtls_pk_can_do( &parent->pk, child->sig_pk ) )
1936 return( -1 );
1937
1938 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
1939 if( rs_ctx != NULL && child->sig_pk == MBEDTLS_PK_ECDSA )
1940 {
1941 return( mbedtls_pk_verify_restartable( &parent->pk,
1942 child->sig_md, hash, mbedtls_md_get_size( md_info ),
1943 child->sig.p, child->sig.len, &rs_ctx->pk ) );
1944 }
1945 #else
1946 (void) rs_ctx;
1947 #endif
1948
1949 return( mbedtls_pk_verify_ext( child->sig_pk, child->sig_opts, &parent->pk,
1950 child->sig_md, hash, mbedtls_md_get_size( md_info ),
1951 child->sig.p, child->sig.len ) );
1952 }
1953
1954 /*
1955 * Check if 'parent' is a suitable parent (signing CA) for 'child'.
1956 * Return 0 if yes, -1 if not.
1957 *
1958 * top means parent is a locally-trusted certificate
1959 */
x509_crt_check_parent(const mbedtls_x509_crt * child,const mbedtls_x509_crt * parent,int top)1960 static int x509_crt_check_parent( const mbedtls_x509_crt *child,
1961 const mbedtls_x509_crt *parent,
1962 int top )
1963 {
1964 int need_ca_bit;
1965
1966 /* Parent must be the issuer */
1967 if( x509_name_cmp( &child->issuer, &parent->subject ) != 0 )
1968 return( -1 );
1969
1970 /* Parent must have the basicConstraints CA bit set as a general rule */
1971 need_ca_bit = 1;
1972
1973 /* Exception: v1/v2 certificates that are locally trusted. */
1974 if( top && parent->version < 3 )
1975 need_ca_bit = 0;
1976
1977 if( need_ca_bit && ! parent->ca_istrue )
1978 return( -1 );
1979
1980 #if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
1981 if( need_ca_bit &&
1982 mbedtls_x509_crt_check_key_usage( parent, MBEDTLS_X509_KU_KEY_CERT_SIGN ) != 0 )
1983 {
1984 return( -1 );
1985 }
1986 #endif
1987
1988 return( 0 );
1989 }
1990
1991 /*
1992 * Find a suitable parent for child in candidates, or return NULL.
1993 *
1994 * Here suitable is defined as:
1995 * 1. subject name matches child's issuer
1996 * 2. if necessary, the CA bit is set and key usage allows signing certs
1997 * 3. for trusted roots, the signature is correct
1998 * (for intermediates, the signature is checked and the result reported)
1999 * 4. pathlen constraints are satisfied
2000 *
2001 * If there's a suitable candidate which is also time-valid, return the first
2002 * such. Otherwise, return the first suitable candidate (or NULL if there is
2003 * none).
2004 *
2005 * The rationale for this rule is that someone could have a list of trusted
2006 * roots with two versions on the same root with different validity periods.
2007 * (At least one user reported having such a list and wanted it to just work.)
2008 * The reason we don't just require time-validity is that generally there is
2009 * only one version, and if it's expired we want the flags to state that
2010 * rather than NOT_TRUSTED, as would be the case if we required it here.
2011 *
2012 * The rationale for rule 3 (signature for trusted roots) is that users might
2013 * have two versions of the same CA with different keys in their list, and the
2014 * way we select the correct one is by checking the signature (as we don't
2015 * rely on key identifier extensions). (This is one way users might choose to
2016 * handle key rollover, another relies on self-issued certs, see [SIRO].)
2017 *
2018 * Arguments:
2019 * - [in] child: certificate for which we're looking for a parent
2020 * - [in] candidates: chained list of potential parents
2021 * - [out] r_parent: parent found (or NULL)
2022 * - [out] r_signature_is_good: 1 if child signature by parent is valid, or 0
2023 * - [in] top: 1 if candidates consists of trusted roots, ie we're at the top
2024 * of the chain, 0 otherwise
2025 * - [in] path_cnt: number of intermediates seen so far
2026 * - [in] self_cnt: number of self-signed intermediates seen so far
2027 * (will never be greater than path_cnt)
2028 * - [in-out] rs_ctx: context for restarting operations
2029 *
2030 * Return value:
2031 * - 0 on success
2032 * - MBEDTLS_ERR_ECP_IN_PROGRESS otherwise
2033 */
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)2034 static int x509_crt_find_parent_in(
2035 mbedtls_x509_crt *child,
2036 mbedtls_x509_crt *candidates,
2037 mbedtls_x509_crt **r_parent,
2038 int *r_signature_is_good,
2039 int top,
2040 unsigned path_cnt,
2041 unsigned self_cnt,
2042 mbedtls_x509_crt_restart_ctx *rs_ctx )
2043 {
2044 int ret;
2045 mbedtls_x509_crt *parent, *fallback_parent;
2046 int signature_is_good, fallback_signature_is_good;
2047
2048 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2049 /* did we have something in progress? */
2050 if( rs_ctx != NULL && rs_ctx->parent != NULL )
2051 {
2052 /* restore saved state */
2053 parent = rs_ctx->parent;
2054 fallback_parent = rs_ctx->fallback_parent;
2055 fallback_signature_is_good = rs_ctx->fallback_signature_is_good;
2056
2057 /* clear saved state */
2058 rs_ctx->parent = NULL;
2059 rs_ctx->fallback_parent = NULL;
2060 rs_ctx->fallback_signature_is_good = 0;
2061
2062 /* resume where we left */
2063 goto check_signature;
2064 }
2065 #endif
2066
2067 fallback_parent = NULL;
2068 fallback_signature_is_good = 0;
2069
2070 for( parent = candidates; parent != NULL; parent = parent->next )
2071 {
2072 /* basic parenting skills (name, CA bit, key usage) */
2073 if( x509_crt_check_parent( child, parent, top ) != 0 )
2074 continue;
2075
2076 /* +1 because stored max_pathlen is 1 higher that the actual value */
2077 if( parent->max_pathlen > 0 &&
2078 (size_t) parent->max_pathlen < 1 + path_cnt - self_cnt )
2079 {
2080 continue;
2081 }
2082
2083 /* Signature */
2084 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2085 check_signature:
2086 #endif
2087 ret = x509_crt_check_signature( child, parent, rs_ctx );
2088
2089 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2090 if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
2091 {
2092 /* save state */
2093 rs_ctx->parent = parent;
2094 rs_ctx->fallback_parent = fallback_parent;
2095 rs_ctx->fallback_signature_is_good = fallback_signature_is_good;
2096
2097 return( ret );
2098 }
2099 #else
2100 (void) ret;
2101 #endif
2102
2103 signature_is_good = ret == 0;
2104 if( top && ! signature_is_good )
2105 continue;
2106
2107 /* optional time check */
2108 if( mbedtls_x509_time_is_past( &parent->valid_to ) ||
2109 mbedtls_x509_time_is_future( &parent->valid_from ) )
2110 {
2111 if( fallback_parent == NULL )
2112 {
2113 fallback_parent = parent;
2114 fallback_signature_is_good = signature_is_good;
2115 }
2116
2117 continue;
2118 }
2119
2120 *r_parent = parent;
2121 *r_signature_is_good = signature_is_good;
2122
2123 break;
2124 }
2125
2126 if( parent == NULL )
2127 {
2128 *r_parent = fallback_parent;
2129 *r_signature_is_good = fallback_signature_is_good;
2130 }
2131
2132 return( 0 );
2133 }
2134
2135 /*
2136 * Find a parent in trusted CAs or the provided chain, or return NULL.
2137 *
2138 * Searches in trusted CAs first, and return the first suitable parent found
2139 * (see find_parent_in() for definition of suitable).
2140 *
2141 * Arguments:
2142 * - [in] child: certificate for which we're looking for a parent, followed
2143 * by a chain of possible intermediates
2144 * - [in] trust_ca: list of locally trusted certificates
2145 * - [out] parent: parent found (or NULL)
2146 * - [out] parent_is_trusted: 1 if returned `parent` is trusted, or 0
2147 * - [out] signature_is_good: 1 if child signature by parent is valid, or 0
2148 * - [in] path_cnt: number of links in the chain so far (EE -> ... -> child)
2149 * - [in] self_cnt: number of self-signed certs in the chain so far
2150 * (will always be no greater than path_cnt)
2151 * - [in-out] rs_ctx: context for restarting operations
2152 *
2153 * Return value:
2154 * - 0 on success
2155 * - MBEDTLS_ERR_ECP_IN_PROGRESS otherwise
2156 */
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)2157 static int x509_crt_find_parent(
2158 mbedtls_x509_crt *child,
2159 mbedtls_x509_crt *trust_ca,
2160 mbedtls_x509_crt **parent,
2161 int *parent_is_trusted,
2162 int *signature_is_good,
2163 unsigned path_cnt,
2164 unsigned self_cnt,
2165 mbedtls_x509_crt_restart_ctx *rs_ctx )
2166 {
2167 int ret;
2168 mbedtls_x509_crt *search_list;
2169
2170 *parent_is_trusted = 1;
2171
2172 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2173 /* restore then clear saved state if we have some stored */
2174 if( rs_ctx != NULL && rs_ctx->parent_is_trusted != -1 )
2175 {
2176 *parent_is_trusted = rs_ctx->parent_is_trusted;
2177 rs_ctx->parent_is_trusted = -1;
2178 }
2179 #endif
2180
2181 while( 1 ) {
2182 search_list = *parent_is_trusted ? trust_ca : child->next;
2183
2184 ret = x509_crt_find_parent_in( child, search_list,
2185 parent, signature_is_good,
2186 *parent_is_trusted,
2187 path_cnt, self_cnt, rs_ctx );
2188
2189 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2190 if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
2191 {
2192 /* save state */
2193 rs_ctx->parent_is_trusted = *parent_is_trusted;
2194 return( ret );
2195 }
2196 #else
2197 (void) ret;
2198 #endif
2199
2200 /* stop here if found or already in second iteration */
2201 if( *parent != NULL || *parent_is_trusted == 0 )
2202 break;
2203
2204 /* prepare second iteration */
2205 *parent_is_trusted = 0;
2206 }
2207
2208 /* extra precaution against mistakes in the caller */
2209 if( *parent == NULL )
2210 {
2211 *parent_is_trusted = 0;
2212 *signature_is_good = 0;
2213 }
2214
2215 return( 0 );
2216 }
2217
2218 /*
2219 * Check if an end-entity certificate is locally trusted
2220 *
2221 * Currently we require such certificates to be self-signed (actually only
2222 * check for self-issued as self-signatures are not checked)
2223 */
x509_crt_check_ee_locally_trusted(mbedtls_x509_crt * crt,mbedtls_x509_crt * trust_ca)2224 static int x509_crt_check_ee_locally_trusted(
2225 mbedtls_x509_crt *crt,
2226 mbedtls_x509_crt *trust_ca )
2227 {
2228 mbedtls_x509_crt *cur;
2229
2230 /* must be self-issued */
2231 if( x509_name_cmp( &crt->issuer, &crt->subject ) != 0 )
2232 return( -1 );
2233
2234 /* look for an exact match with trusted cert */
2235 for( cur = trust_ca; cur != NULL; cur = cur->next )
2236 {
2237 if( crt->raw.len == cur->raw.len &&
2238 memcmp( crt->raw.p, cur->raw.p, crt->raw.len ) == 0 )
2239 {
2240 return( 0 );
2241 }
2242 }
2243
2244 /* too bad */
2245 return( -1 );
2246 }
2247
2248 /*
2249 * Build and verify a certificate chain
2250 *
2251 * Given a peer-provided list of certificates EE, C1, ..., Cn and
2252 * a list of trusted certs R1, ... Rp, try to build and verify a chain
2253 * EE, Ci1, ... Ciq [, Rj]
2254 * such that every cert in the chain is a child of the next one,
2255 * jumping to a trusted root as early as possible.
2256 *
2257 * Verify that chain and return it with flags for all issues found.
2258 *
2259 * Special cases:
2260 * - EE == Rj -> return a one-element list containing it
2261 * - EE, Ci1, ..., Ciq cannot be continued with a trusted root
2262 * -> return that chain with NOT_TRUSTED set on Ciq
2263 *
2264 * Tests for (aspects of) this function should include at least:
2265 * - trusted EE
2266 * - EE -> trusted root
2267 * - EE -> intermediate CA -> trusted root
2268 * - if relevant: EE untrusted
2269 * - if relevant: EE -> intermediate, untrusted
2270 * with the aspect under test checked at each relevant level (EE, int, root).
2271 * For some aspects longer chains are required, but usually length 2 is
2272 * enough (but length 1 is not in general).
2273 *
2274 * Arguments:
2275 * - [in] crt: the cert list EE, C1, ..., Cn
2276 * - [in] trust_ca: the trusted list R1, ..., Rp
2277 * - [in] ca_crl, profile: as in verify_with_profile()
2278 * - [out] ver_chain: the built and verified chain
2279 * Only valid when return value is 0, may contain garbage otherwise!
2280 * Restart note: need not be the same when calling again to resume.
2281 * - [in-out] rs_ctx: context for restarting operations
2282 *
2283 * Return value:
2284 * - non-zero if the chain could not be fully built and examined
2285 * - 0 is the chain was successfully built and examined,
2286 * even if it was found to be invalid
2287 */
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)2288 static int x509_crt_verify_chain(
2289 mbedtls_x509_crt *crt,
2290 mbedtls_x509_crt *trust_ca,
2291 mbedtls_x509_crl *ca_crl,
2292 const mbedtls_x509_crt_profile *profile,
2293 mbedtls_x509_crt_verify_chain *ver_chain,
2294 mbedtls_x509_crt_restart_ctx *rs_ctx )
2295 {
2296 /* Don't initialize any of those variables here, so that the compiler can
2297 * catch potential issues with jumping ahead when restarting */
2298 int ret;
2299 uint32_t *flags;
2300 mbedtls_x509_crt_verify_chain_item *cur;
2301 mbedtls_x509_crt *child;
2302 mbedtls_x509_crt *parent;
2303 int parent_is_trusted;
2304 int child_is_trusted;
2305 int signature_is_good;
2306 unsigned self_cnt;
2307
2308 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2309 /* resume if we had an operation in progress */
2310 if( rs_ctx != NULL && rs_ctx->in_progress == x509_crt_rs_find_parent )
2311 {
2312 /* restore saved state */
2313 *ver_chain = rs_ctx->ver_chain; /* struct copy */
2314 self_cnt = rs_ctx->self_cnt;
2315
2316 /* restore derived state */
2317 cur = &ver_chain->items[ver_chain->len - 1];
2318 child = cur->crt;
2319 flags = &cur->flags;
2320
2321 goto find_parent;
2322 }
2323 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
2324
2325 child = crt;
2326 self_cnt = 0;
2327 parent_is_trusted = 0;
2328 child_is_trusted = 0;
2329
2330 while( 1 ) {
2331 /* Add certificate to the verification chain */
2332 cur = &ver_chain->items[ver_chain->len];
2333 cur->crt = child;
2334 cur->flags = 0;
2335 ver_chain->len++;
2336 flags = &cur->flags;
2337
2338 /* Check time-validity (all certificates) */
2339 if( mbedtls_x509_time_is_past( &child->valid_to ) )
2340 *flags |= MBEDTLS_X509_BADCERT_EXPIRED;
2341
2342 if( mbedtls_x509_time_is_future( &child->valid_from ) )
2343 *flags |= MBEDTLS_X509_BADCERT_FUTURE;
2344
2345 /* Stop here for trusted roots (but not for trusted EE certs) */
2346 if( child_is_trusted )
2347 return( 0 );
2348
2349 /* Check signature algorithm: MD & PK algs */
2350 if( x509_profile_check_md_alg( profile, child->sig_md ) != 0 )
2351 *flags |= MBEDTLS_X509_BADCERT_BAD_MD;
2352
2353 if( x509_profile_check_pk_alg( profile, child->sig_pk ) != 0 )
2354 *flags |= MBEDTLS_X509_BADCERT_BAD_PK;
2355
2356 /* Special case: EE certs that are locally trusted */
2357 if( ver_chain->len == 1 &&
2358 x509_crt_check_ee_locally_trusted( child, trust_ca ) == 0 )
2359 {
2360 return( 0 );
2361 }
2362
2363 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2364 find_parent:
2365 #endif
2366 /* Look for a parent in trusted CAs or up the chain */
2367 ret = x509_crt_find_parent( child, trust_ca, &parent,
2368 &parent_is_trusted, &signature_is_good,
2369 ver_chain->len - 1, self_cnt, rs_ctx );
2370
2371 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2372 if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
2373 {
2374 /* save state */
2375 rs_ctx->in_progress = x509_crt_rs_find_parent;
2376 rs_ctx->self_cnt = self_cnt;
2377 rs_ctx->ver_chain = *ver_chain; /* struct copy */
2378
2379 return( ret );
2380 }
2381 #else
2382 (void) ret;
2383 #endif
2384
2385 /* No parent? We're done here */
2386 if( parent == NULL )
2387 {
2388 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
2389 return( 0 );
2390 }
2391
2392 /* Count intermediate self-issued (not necessarily self-signed) certs.
2393 * These can occur with some strategies for key rollover, see [SIRO],
2394 * and should be excluded from max_pathlen checks. */
2395 if( ver_chain->len != 1 &&
2396 x509_name_cmp( &child->issuer, &child->subject ) == 0 )
2397 {
2398 self_cnt++;
2399 }
2400
2401 /* path_cnt is 0 for the first intermediate CA,
2402 * and if parent is trusted it's not an intermediate CA */
2403 if( ! parent_is_trusted &&
2404 ver_chain->len > MBEDTLS_X509_MAX_INTERMEDIATE_CA )
2405 {
2406 /* return immediately to avoid overflow the chain array */
2407 return( MBEDTLS_ERR_X509_FATAL_ERROR );
2408 }
2409
2410 /* signature was checked while searching parent */
2411 if( ! signature_is_good )
2412 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
2413
2414 /* check size of signing key */
2415 if( x509_profile_check_key( profile, &parent->pk ) != 0 )
2416 *flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
2417
2418 #if defined(MBEDTLS_X509_CRL_PARSE_C)
2419 /* Check trusted CA's CRL for the given crt */
2420 *flags |= x509_crt_verifycrl( child, parent, ca_crl, profile );
2421 #else
2422 (void) ca_crl;
2423 #endif
2424
2425 /* prepare for next iteration */
2426 child = parent;
2427 parent = NULL;
2428 child_is_trusted = parent_is_trusted;
2429 signature_is_good = 0;
2430 }
2431 }
2432
2433 /*
2434 * Check for CN match
2435 */
x509_crt_check_cn(const mbedtls_x509_buf * name,const char * cn,size_t cn_len)2436 static int x509_crt_check_cn( const mbedtls_x509_buf *name,
2437 const char *cn, size_t cn_len )
2438 {
2439 /* try exact match */
2440 if( name->len == cn_len &&
2441 x509_memcasecmp( cn, name->p, cn_len ) == 0 )
2442 {
2443 return( 0 );
2444 }
2445
2446 /* try wildcard match */
2447 if( x509_check_wildcard( cn, name ) == 0 )
2448 {
2449 return( 0 );
2450 }
2451
2452 return( -1 );
2453 }
2454
2455 /*
2456 * Verify the requested CN - only call this if cn is not NULL!
2457 */
x509_crt_verify_name(const mbedtls_x509_crt * crt,const char * cn,uint32_t * flags)2458 static void x509_crt_verify_name( const mbedtls_x509_crt *crt,
2459 const char *cn,
2460 uint32_t *flags )
2461 {
2462 const mbedtls_x509_name *name;
2463 const mbedtls_x509_sequence *cur;
2464 size_t cn_len = strlen( cn );
2465
2466 if( crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME )
2467 {
2468 for( cur = &crt->subject_alt_names; cur != NULL; cur = cur->next )
2469 {
2470 if( x509_crt_check_cn( &cur->buf, cn, cn_len ) == 0 )
2471 break;
2472 }
2473
2474 if( cur == NULL )
2475 *flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH;
2476 }
2477 else
2478 {
2479 for( name = &crt->subject; name != NULL; name = name->next )
2480 {
2481 if( MBEDTLS_OID_CMP( MBEDTLS_OID_AT_CN, &name->oid ) == 0 &&
2482 x509_crt_check_cn( &name->val, cn, cn_len ) == 0 )
2483 {
2484 break;
2485 }
2486 }
2487
2488 if( name == NULL )
2489 *flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH;
2490 }
2491 }
2492
2493 /*
2494 * Merge the flags for all certs in the chain, after calling callback
2495 */
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)2496 static int x509_crt_merge_flags_with_cb(
2497 uint32_t *flags,
2498 const mbedtls_x509_crt_verify_chain *ver_chain,
2499 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2500 void *p_vrfy )
2501 {
2502 int ret;
2503 unsigned i;
2504 uint32_t cur_flags;
2505 const mbedtls_x509_crt_verify_chain_item *cur;
2506
2507 for( i = ver_chain->len; i != 0; --i )
2508 {
2509 cur = &ver_chain->items[i-1];
2510 cur_flags = cur->flags;
2511
2512 if( NULL != f_vrfy )
2513 if( ( ret = f_vrfy( p_vrfy, cur->crt, (int) i-1, &cur_flags ) ) != 0 )
2514 return( ret );
2515
2516 *flags |= cur_flags;
2517 }
2518
2519 return( 0 );
2520 }
2521
2522 /*
2523 * Verify the certificate validity (default profile, not restartable)
2524 */
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)2525 int mbedtls_x509_crt_verify( mbedtls_x509_crt *crt,
2526 mbedtls_x509_crt *trust_ca,
2527 mbedtls_x509_crl *ca_crl,
2528 const char *cn, uint32_t *flags,
2529 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2530 void *p_vrfy )
2531 {
2532 return( mbedtls_x509_crt_verify_restartable( crt, trust_ca, ca_crl,
2533 &mbedtls_x509_crt_profile_default, cn, flags,
2534 f_vrfy, p_vrfy, NULL ) );
2535 }
2536
2537 /*
2538 * Verify the certificate validity (user-chosen profile, not restartable)
2539 */
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)2540 int mbedtls_x509_crt_verify_with_profile( mbedtls_x509_crt *crt,
2541 mbedtls_x509_crt *trust_ca,
2542 mbedtls_x509_crl *ca_crl,
2543 const mbedtls_x509_crt_profile *profile,
2544 const char *cn, uint32_t *flags,
2545 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2546 void *p_vrfy )
2547 {
2548 return( mbedtls_x509_crt_verify_restartable( crt, trust_ca, ca_crl,
2549 profile, cn, flags, f_vrfy, p_vrfy, NULL ) );
2550 }
2551
2552 /*
2553 * Verify the certificate validity, with profile, restartable version
2554 *
2555 * This function:
2556 * - checks the requested CN (if any)
2557 * - checks the type and size of the EE cert's key,
2558 * as that isn't done as part of chain building/verification currently
2559 * - builds and verifies the chain
2560 * - then calls the callback and merges the flags
2561 */
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)2562 int mbedtls_x509_crt_verify_restartable( mbedtls_x509_crt *crt,
2563 mbedtls_x509_crt *trust_ca,
2564 mbedtls_x509_crl *ca_crl,
2565 const mbedtls_x509_crt_profile *profile,
2566 const char *cn, uint32_t *flags,
2567 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2568 void *p_vrfy,
2569 mbedtls_x509_crt_restart_ctx *rs_ctx )
2570 {
2571 int ret;
2572 mbedtls_pk_type_t pk_type;
2573 mbedtls_x509_crt_verify_chain ver_chain;
2574 uint32_t ee_flags;
2575
2576 *flags = 0;
2577 ee_flags = 0;
2578 x509_crt_verify_chain_reset( &ver_chain );
2579
2580 if( profile == NULL )
2581 {
2582 ret = MBEDTLS_ERR_X509_BAD_INPUT_DATA;
2583 goto exit;
2584 }
2585
2586 /* check name if requested */
2587 if( cn != NULL )
2588 x509_crt_verify_name( crt, cn, &ee_flags );
2589
2590 /* Check the type and size of the key */
2591 pk_type = mbedtls_pk_get_type( &crt->pk );
2592
2593 if( x509_profile_check_pk_alg( profile, pk_type ) != 0 )
2594 ee_flags |= MBEDTLS_X509_BADCERT_BAD_PK;
2595
2596 if( x509_profile_check_key( profile, &crt->pk ) != 0 )
2597 ee_flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
2598
2599 /* Check the chain */
2600 ret = x509_crt_verify_chain( crt, trust_ca, ca_crl, profile,
2601 &ver_chain, rs_ctx );
2602
2603 if( ret != 0 )
2604 goto exit;
2605
2606 /* Merge end-entity flags */
2607 ver_chain.items[0].flags |= ee_flags;
2608
2609 /* Build final flags, calling callback on the way if any */
2610 ret = x509_crt_merge_flags_with_cb( flags, &ver_chain, f_vrfy, p_vrfy );
2611
2612 exit:
2613 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2614 if( rs_ctx != NULL && ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
2615 mbedtls_x509_crt_restart_free( rs_ctx );
2616 #endif
2617
2618 /* prevent misuse of the vrfy callback - VERIFY_FAILED would be ignored by
2619 * the SSL module for authmode optional, but non-zero return from the
2620 * callback means a fatal error so it shouldn't be ignored */
2621 if( ret == MBEDTLS_ERR_X509_CERT_VERIFY_FAILED )
2622 ret = MBEDTLS_ERR_X509_FATAL_ERROR;
2623
2624 if( ret != 0 )
2625 {
2626 *flags = (uint32_t) -1;
2627 return( ret );
2628 }
2629
2630 if( *flags != 0 )
2631 return( MBEDTLS_ERR_X509_CERT_VERIFY_FAILED );
2632
2633 return( 0 );
2634 }
2635
2636 /*
2637 * Initialize a certificate chain
2638 */
mbedtls_x509_crt_init(mbedtls_x509_crt * crt)2639 void mbedtls_x509_crt_init( mbedtls_x509_crt *crt )
2640 {
2641 memset( crt, 0, sizeof(mbedtls_x509_crt) );
2642 }
2643
2644 /*
2645 * Unallocate all certificate data
2646 */
mbedtls_x509_crt_free(mbedtls_x509_crt * crt)2647 void mbedtls_x509_crt_free( mbedtls_x509_crt *crt )
2648 {
2649 mbedtls_x509_crt *cert_cur = crt;
2650 mbedtls_x509_crt *cert_prv;
2651 mbedtls_x509_name *name_cur;
2652 mbedtls_x509_name *name_prv;
2653 mbedtls_x509_sequence *seq_cur;
2654 mbedtls_x509_sequence *seq_prv;
2655
2656 if( crt == NULL )
2657 return;
2658
2659 do
2660 {
2661 mbedtls_pk_free( &cert_cur->pk );
2662
2663 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
2664 mbedtls_free( cert_cur->sig_opts );
2665 #endif
2666
2667 name_cur = cert_cur->issuer.next;
2668 while( name_cur != NULL )
2669 {
2670 name_prv = name_cur;
2671 name_cur = name_cur->next;
2672 mbedtls_platform_zeroize( name_prv, sizeof( mbedtls_x509_name ) );
2673 mbedtls_free( name_prv );
2674 }
2675
2676 name_cur = cert_cur->subject.next;
2677 while( name_cur != NULL )
2678 {
2679 name_prv = name_cur;
2680 name_cur = name_cur->next;
2681 mbedtls_platform_zeroize( name_prv, sizeof( mbedtls_x509_name ) );
2682 mbedtls_free( name_prv );
2683 }
2684
2685 seq_cur = cert_cur->ext_key_usage.next;
2686 while( seq_cur != NULL )
2687 {
2688 seq_prv = seq_cur;
2689 seq_cur = seq_cur->next;
2690 mbedtls_platform_zeroize( seq_prv,
2691 sizeof( mbedtls_x509_sequence ) );
2692 mbedtls_free( seq_prv );
2693 }
2694
2695 seq_cur = cert_cur->subject_alt_names.next;
2696 while( seq_cur != NULL )
2697 {
2698 seq_prv = seq_cur;
2699 seq_cur = seq_cur->next;
2700 mbedtls_platform_zeroize( seq_prv,
2701 sizeof( mbedtls_x509_sequence ) );
2702 mbedtls_free( seq_prv );
2703 }
2704
2705 if( cert_cur->raw.p != NULL )
2706 {
2707 mbedtls_platform_zeroize( cert_cur->raw.p, cert_cur->raw.len );
2708 mbedtls_free( cert_cur->raw.p );
2709 }
2710
2711 cert_cur = cert_cur->next;
2712 }
2713 while( cert_cur != NULL );
2714
2715 cert_cur = crt;
2716 do
2717 {
2718 cert_prv = cert_cur;
2719 cert_cur = cert_cur->next;
2720
2721 mbedtls_platform_zeroize( cert_prv, sizeof( mbedtls_x509_crt ) );
2722 if( cert_prv != crt )
2723 mbedtls_free( cert_prv );
2724 }
2725 while( cert_cur != NULL );
2726 }
2727
2728 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2729 /*
2730 * Initialize a restart context
2731 */
mbedtls_x509_crt_restart_init(mbedtls_x509_crt_restart_ctx * ctx)2732 void mbedtls_x509_crt_restart_init( mbedtls_x509_crt_restart_ctx *ctx )
2733 {
2734 mbedtls_pk_restart_init( &ctx->pk );
2735
2736 ctx->parent = NULL;
2737 ctx->fallback_parent = NULL;
2738 ctx->fallback_signature_is_good = 0;
2739
2740 ctx->parent_is_trusted = -1;
2741
2742 ctx->in_progress = x509_crt_rs_none;
2743 ctx->self_cnt = 0;
2744 x509_crt_verify_chain_reset( &ctx->ver_chain );
2745 }
2746
2747 /*
2748 * Free the components of a restart context
2749 */
mbedtls_x509_crt_restart_free(mbedtls_x509_crt_restart_ctx * ctx)2750 void mbedtls_x509_crt_restart_free( mbedtls_x509_crt_restart_ctx *ctx )
2751 {
2752 if( ctx == NULL )
2753 return;
2754
2755 mbedtls_pk_restart_free( &ctx->pk );
2756 mbedtls_x509_crt_restart_init( ctx );
2757 }
2758 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
2759
2760 #endif /* MBEDTLS_X509_CRT_PARSE_C */
2761