1 /*
2 * X.509 certificate parsing and verification
3 *
4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
5 * SPDX-License-Identifier: Apache-2.0
6 *
7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
8 * not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 *
19 * This file is part of mbed TLS (https://tls.mbed.org)
20 */
21 /*
22 * The ITU-T X.509 standard defines a certificate format for PKI.
23 *
24 * http://www.ietf.org/rfc/rfc5280.txt (Certificates and CRLs)
25 * http://www.ietf.org/rfc/rfc3279.txt (Alg IDs for CRLs)
26 * http://www.ietf.org/rfc/rfc2986.txt (CSRs, aka PKCS#10)
27 *
28 * http://www.itu.int/ITU-T/studygroups/com17/languages/X.680-0207.pdf
29 * http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf
30 */
31
32 #if !defined(MBEDTLS_CONFIG_FILE)
33 #include "mbedtls/config.h"
34 #else
35 #include MBEDTLS_CONFIG_FILE
36 #endif
37
38 #if defined(MBEDTLS_X509_CRT_PARSE_C)
39
40 #include "mbedtls/x509_crt.h"
41 #include "mbedtls/oid.h"
42
43 #include <stdio.h>
44 #include <string.h>
45
46 #if defined(MBEDTLS_PEM_PARSE_C)
47 #include "mbedtls/pem.h"
48 #endif
49
50 #if defined(MBEDTLS_PLATFORM_C)
51 #include "mbedtls/platform.h"
52 #else
53 #include <stdlib.h>
54 #define mbedtls_free free
55 #define mbedtls_calloc calloc
56 #define mbedtls_snprintf snprintf
57 #endif
58
59 #if defined(MBEDTLS_THREADING_C)
60 #include "mbedtls/threading.h"
61 #endif
62
63 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
64 #include <windows.h>
65 #else
66 #include <time.h>
67 #endif
68
69 #if defined(MBEDTLS_FS_IO)
70 #include <stdio.h>
71 #if !defined(_WIN32) || defined(EFIX64) || defined(EFI32)
72 #include <sys/types.h>
73 #include <sys/stat.h>
74 #include <dirent.h>
75 #endif /* !_WIN32 || EFIX64 || EFI32 */
76 #endif
77
78 /* Implementation that should never be optimized out by the compiler */
mbedtls_zeroize(void * v,size_t n)79 static void mbedtls_zeroize( void *v, size_t n ) {
80 volatile unsigned char *p = v; while( n-- ) *p++ = 0;
81 }
82
83 /*
84 * Default profile
85 */
86 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_default =
87 {
88 /* Hashes from SHA-1 and above */
89 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA1 ) |
90 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_RIPEMD160 ) |
91 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA224 ) |
92 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
93 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ) |
94 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA512 ),
95 0xFFFFFFF, /* Any PK alg */
96 0xFFFFFFF, /* Any curve */
97 2048,
98 };
99
100 /*
101 * Next-default profile
102 */
103 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_next =
104 {
105 /* Hashes from SHA-256 and above */
106 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
107 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ) |
108 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA512 ),
109 0xFFFFFFF, /* Any PK alg */
110 #if defined(MBEDTLS_ECP_C)
111 /* Curves at or above 128-bit security level */
112 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256R1 ) |
113 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP384R1 ) |
114 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP521R1 ) |
115 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP256R1 ) |
116 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP384R1 ) |
117 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP512R1 ) |
118 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256K1 ),
119 #else
120 0,
121 #endif
122 2048,
123 };
124
125 /*
126 * NSA Suite B Profile
127 */
128 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_suiteb =
129 {
130 /* Only SHA-256 and 384 */
131 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
132 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ),
133 /* Only ECDSA */
134 MBEDTLS_X509_ID_FLAG( MBEDTLS_PK_ECDSA ),
135 #if defined(MBEDTLS_ECP_C)
136 /* Only NIST P-256 and P-384 */
137 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256R1 ) |
138 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP384R1 ),
139 #else
140 0,
141 #endif
142 0,
143 };
144
145 /*
146 * Check md_alg against profile
147 * Return 0 if md_alg acceptable for this profile, -1 otherwise
148 */
x509_profile_check_md_alg(const mbedtls_x509_crt_profile * profile,mbedtls_md_type_t md_alg)149 static int x509_profile_check_md_alg( const mbedtls_x509_crt_profile *profile,
150 mbedtls_md_type_t md_alg )
151 {
152 if( ( profile->allowed_mds & MBEDTLS_X509_ID_FLAG( md_alg ) ) != 0 )
153 return( 0 );
154
155 return( -1 );
156 }
157
158 /*
159 * Check pk_alg against profile
160 * Return 0 if pk_alg acceptable for this profile, -1 otherwise
161 */
x509_profile_check_pk_alg(const mbedtls_x509_crt_profile * profile,mbedtls_pk_type_t pk_alg)162 static int x509_profile_check_pk_alg( const mbedtls_x509_crt_profile *profile,
163 mbedtls_pk_type_t pk_alg )
164 {
165 if( ( profile->allowed_pks & MBEDTLS_X509_ID_FLAG( pk_alg ) ) != 0 )
166 return( 0 );
167
168 return( -1 );
169 }
170
171 /*
172 * Check key against profile
173 * Return 0 if pk_alg acceptable for this profile, -1 otherwise
174 */
x509_profile_check_key(const mbedtls_x509_crt_profile * profile,mbedtls_pk_type_t pk_alg,const mbedtls_pk_context * pk)175 static int x509_profile_check_key( const mbedtls_x509_crt_profile *profile,
176 mbedtls_pk_type_t pk_alg,
177 const mbedtls_pk_context *pk )
178 {
179 #if defined(MBEDTLS_RSA_C)
180 if( pk_alg == MBEDTLS_PK_RSA || pk_alg == MBEDTLS_PK_RSASSA_PSS )
181 {
182 if( mbedtls_pk_get_bitlen( pk ) >= profile->rsa_min_bitlen )
183 return( 0 );
184
185 return( -1 );
186 }
187 #endif
188
189 #if defined(MBEDTLS_ECP_C)
190 if( pk_alg == MBEDTLS_PK_ECDSA ||
191 pk_alg == MBEDTLS_PK_ECKEY ||
192 pk_alg == MBEDTLS_PK_ECKEY_DH )
193 {
194 mbedtls_ecp_group_id gid = mbedtls_pk_ec( *pk )->grp.id;
195
196 if( ( profile->allowed_curves & MBEDTLS_X509_ID_FLAG( gid ) ) != 0 )
197 return( 0 );
198
199 return( -1 );
200 }
201 #endif
202
203 return( -1 );
204 }
205
206 /*
207 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
208 */
x509_get_version(unsigned char ** p,const unsigned char * end,int * ver)209 static int x509_get_version( unsigned char **p,
210 const unsigned char *end,
211 int *ver )
212 {
213 int ret;
214 size_t len;
215
216 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
217 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 0 ) ) != 0 )
218 {
219 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
220 {
221 *ver = 0;
222 return( 0 );
223 }
224
225 return( ret );
226 }
227
228 end = *p + len;
229
230 if( ( ret = mbedtls_asn1_get_int( p, end, ver ) ) != 0 )
231 return( MBEDTLS_ERR_X509_INVALID_VERSION + ret );
232
233 if( *p != end )
234 return( MBEDTLS_ERR_X509_INVALID_VERSION +
235 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
236
237 return( 0 );
238 }
239
240 /*
241 * Validity ::= SEQUENCE {
242 * notBefore Time,
243 * notAfter Time }
244 */
x509_get_dates(unsigned char ** p,const unsigned char * end,mbedtls_x509_time * from,mbedtls_x509_time * to)245 static int x509_get_dates( unsigned char **p,
246 const unsigned char *end,
247 mbedtls_x509_time *from,
248 mbedtls_x509_time *to )
249 {
250 int ret;
251 size_t len;
252
253 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
254 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
255 return( MBEDTLS_ERR_X509_INVALID_DATE + ret );
256
257 end = *p + len;
258
259 if( ( ret = mbedtls_x509_get_time( p, end, from ) ) != 0 )
260 return( ret );
261
262 if( ( ret = mbedtls_x509_get_time( p, end, to ) ) != 0 )
263 return( ret );
264
265 if( *p != end )
266 return( MBEDTLS_ERR_X509_INVALID_DATE +
267 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
268
269 return( 0 );
270 }
271
272 /*
273 * X.509 v2/v3 unique identifier (not parsed)
274 */
x509_get_uid(unsigned char ** p,const unsigned char * end,mbedtls_x509_buf * uid,int n)275 static int x509_get_uid( unsigned char **p,
276 const unsigned char *end,
277 mbedtls_x509_buf *uid, int n )
278 {
279 int ret;
280
281 if( *p == end )
282 return( 0 );
283
284 uid->tag = **p;
285
286 if( ( ret = mbedtls_asn1_get_tag( p, end, &uid->len,
287 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | n ) ) != 0 )
288 {
289 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
290 return( 0 );
291
292 return( ret );
293 }
294
295 uid->p = *p;
296 *p += uid->len;
297
298 return( 0 );
299 }
300
x509_get_basic_constraints(unsigned char ** p,const unsigned char * end,int * ca_istrue,int * max_pathlen)301 static int x509_get_basic_constraints( unsigned char **p,
302 const unsigned char *end,
303 int *ca_istrue,
304 int *max_pathlen )
305 {
306 int ret;
307 size_t len;
308
309 /*
310 * BasicConstraints ::= SEQUENCE {
311 * cA BOOLEAN DEFAULT FALSE,
312 * pathLenConstraint INTEGER (0..MAX) OPTIONAL }
313 */
314 *ca_istrue = 0; /* DEFAULT FALSE */
315 *max_pathlen = 0; /* endless */
316
317 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
318 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
319 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
320
321 if( *p == end )
322 return( 0 );
323
324 if( ( ret = mbedtls_asn1_get_bool( p, end, ca_istrue ) ) != 0 )
325 {
326 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
327 ret = mbedtls_asn1_get_int( p, end, ca_istrue );
328
329 if( ret != 0 )
330 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
331
332 if( *ca_istrue != 0 )
333 *ca_istrue = 1;
334 }
335
336 if( *p == end )
337 return( 0 );
338
339 if( ( ret = mbedtls_asn1_get_int( p, end, max_pathlen ) ) != 0 )
340 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
341
342 if( *p != end )
343 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
344 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
345
346 (*max_pathlen)++;
347
348 return( 0 );
349 }
350
x509_get_ns_cert_type(unsigned char ** p,const unsigned char * end,unsigned char * ns_cert_type)351 static int x509_get_ns_cert_type( unsigned char **p,
352 const unsigned char *end,
353 unsigned char *ns_cert_type)
354 {
355 int ret;
356 mbedtls_x509_bitstring bs = { 0, 0, NULL };
357
358 if( ( ret = mbedtls_asn1_get_bitstring( p, end, &bs ) ) != 0 )
359 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
360
361 if( bs.len != 1 )
362 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
363 MBEDTLS_ERR_ASN1_INVALID_LENGTH );
364
365 /* Get actual bitstring */
366 *ns_cert_type = *bs.p;
367 return( 0 );
368 }
369
x509_get_key_usage(unsigned char ** p,const unsigned char * end,unsigned int * key_usage)370 static int x509_get_key_usage( unsigned char **p,
371 const unsigned char *end,
372 unsigned int *key_usage)
373 {
374 int ret;
375 size_t i;
376 mbedtls_x509_bitstring bs = { 0, 0, NULL };
377
378 if( ( ret = mbedtls_asn1_get_bitstring( p, end, &bs ) ) != 0 )
379 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
380
381 if( bs.len < 1 )
382 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
383 MBEDTLS_ERR_ASN1_INVALID_LENGTH );
384
385 /* Get actual bitstring */
386 *key_usage = 0;
387 for( i = 0; i < bs.len && i < sizeof( unsigned int ); i++ )
388 {
389 *key_usage |= (unsigned int) bs.p[i] << (8*i);
390 }
391
392 return( 0 );
393 }
394
395 /*
396 * ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId
397 *
398 * KeyPurposeId ::= OBJECT IDENTIFIER
399 */
x509_get_ext_key_usage(unsigned char ** p,const unsigned char * end,mbedtls_x509_sequence * ext_key_usage)400 static int x509_get_ext_key_usage( unsigned char **p,
401 const unsigned char *end,
402 mbedtls_x509_sequence *ext_key_usage)
403 {
404 int ret;
405
406 if( ( ret = mbedtls_asn1_get_sequence_of( p, end, ext_key_usage, MBEDTLS_ASN1_OID ) ) != 0 )
407 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
408
409 /* Sequence length must be >= 1 */
410 if( ext_key_usage->buf.p == NULL )
411 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
412 MBEDTLS_ERR_ASN1_INVALID_LENGTH );
413
414 return( 0 );
415 }
416
417 /*
418 * SubjectAltName ::= GeneralNames
419 *
420 * GeneralNames ::= SEQUENCE SIZE (1..MAX) OF GeneralName
421 *
422 * GeneralName ::= CHOICE {
423 * otherName [0] OtherName,
424 * rfc822Name [1] IA5String,
425 * dNSName [2] IA5String,
426 * x400Address [3] ORAddress,
427 * directoryName [4] Name,
428 * ediPartyName [5] EDIPartyName,
429 * uniformResourceIdentifier [6] IA5String,
430 * iPAddress [7] OCTET STRING,
431 * registeredID [8] OBJECT IDENTIFIER }
432 *
433 * OtherName ::= SEQUENCE {
434 * type-id OBJECT IDENTIFIER,
435 * value [0] EXPLICIT ANY DEFINED BY type-id }
436 *
437 * EDIPartyName ::= SEQUENCE {
438 * nameAssigner [0] DirectoryString OPTIONAL,
439 * partyName [1] DirectoryString }
440 *
441 * NOTE: we only parse and use dNSName at this point.
442 */
x509_get_subject_alt_name(unsigned char ** p,const unsigned char * end,mbedtls_x509_sequence * subject_alt_name)443 static int x509_get_subject_alt_name( unsigned char **p,
444 const unsigned char *end,
445 mbedtls_x509_sequence *subject_alt_name )
446 {
447 int ret;
448 size_t len, tag_len;
449 mbedtls_asn1_buf *buf;
450 unsigned char tag;
451 mbedtls_asn1_sequence *cur = subject_alt_name;
452
453 /* Get main sequence tag */
454 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
455 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
456 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
457
458 if( *p + len != end )
459 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
460 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
461
462 while( *p < end )
463 {
464 if( ( end - *p ) < 1 )
465 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
466 MBEDTLS_ERR_ASN1_OUT_OF_DATA );
467
468 tag = **p;
469 (*p)++;
470 if( ( ret = mbedtls_asn1_get_len( p, end, &tag_len ) ) != 0 )
471 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
472
473 if( ( tag & MBEDTLS_ASN1_CONTEXT_SPECIFIC ) != MBEDTLS_ASN1_CONTEXT_SPECIFIC )
474 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
475 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
476
477 /* Skip everything but DNS name */
478 if( tag != ( MBEDTLS_ASN1_CONTEXT_SPECIFIC | 2 ) )
479 {
480 *p += tag_len;
481 continue;
482 }
483
484 /* Allocate and assign next pointer */
485 if( cur->buf.p != NULL )
486 {
487 if( cur->next != NULL )
488 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS );
489
490 cur->next = mbedtls_calloc( 1, sizeof( mbedtls_asn1_sequence ) );
491
492 if( cur->next == NULL )
493 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
494 MBEDTLS_ERR_ASN1_ALLOC_FAILED );
495
496 cur = cur->next;
497 }
498
499 buf = &(cur->buf);
500 buf->tag = tag;
501 buf->p = *p;
502 buf->len = tag_len;
503 *p += buf->len;
504 }
505
506 /* Set final sequence entry's next pointer to NULL */
507 cur->next = NULL;
508
509 if( *p != end )
510 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
511 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
512
513 return( 0 );
514 }
515
516 /*
517 * X.509 v3 extensions
518 *
519 */
x509_get_crt_ext(unsigned char ** p,const unsigned char * end,mbedtls_x509_crt * crt)520 static int x509_get_crt_ext( unsigned char **p,
521 const unsigned char *end,
522 mbedtls_x509_crt *crt )
523 {
524 int ret;
525 size_t len;
526 unsigned char *end_ext_data, *end_ext_octet;
527
528 if( ( ret = mbedtls_x509_get_ext( p, end, &crt->v3_ext, 3 ) ) != 0 )
529 {
530 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
531 return( 0 );
532
533 return( ret );
534 }
535
536 while( *p < end )
537 {
538 /*
539 * Extension ::= SEQUENCE {
540 * extnID OBJECT IDENTIFIER,
541 * critical BOOLEAN DEFAULT FALSE,
542 * extnValue OCTET STRING }
543 */
544 mbedtls_x509_buf extn_oid = {0, 0, NULL};
545 int is_critical = 0; /* DEFAULT FALSE */
546 int ext_type = 0;
547
548 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
549 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
550 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
551
552 end_ext_data = *p + len;
553
554 /* Get extension ID */
555 extn_oid.tag = **p;
556
557 if( ( ret = mbedtls_asn1_get_tag( p, end, &extn_oid.len, MBEDTLS_ASN1_OID ) ) != 0 )
558 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
559
560 extn_oid.p = *p;
561 *p += extn_oid.len;
562
563 if( ( end - *p ) < 1 )
564 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
565 MBEDTLS_ERR_ASN1_OUT_OF_DATA );
566
567 /* Get optional critical */
568 if( ( ret = mbedtls_asn1_get_bool( p, end_ext_data, &is_critical ) ) != 0 &&
569 ( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) )
570 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
571
572 /* Data should be octet string type */
573 if( ( ret = mbedtls_asn1_get_tag( p, end_ext_data, &len,
574 MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
575 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS + ret );
576
577 end_ext_octet = *p + len;
578
579 if( end_ext_octet != end_ext_data )
580 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
581 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
582
583 /*
584 * Detect supported extensions
585 */
586 ret = mbedtls_oid_get_x509_ext_type( &extn_oid, &ext_type );
587
588 if( ret != 0 )
589 {
590 /* No parser found, skip extension */
591 *p = end_ext_octet;
592
593 #if !defined(MBEDTLS_X509_ALLOW_UNSUPPORTED_CRITICAL_EXTENSION)
594 if( is_critical )
595 {
596 /* Data is marked as critical: fail */
597 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
598 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
599 }
600 #endif
601 continue;
602 }
603
604 /* Forbid repeated extensions */
605 if( ( crt->ext_types & ext_type ) != 0 )
606 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS );
607
608 crt->ext_types |= ext_type;
609
610 switch( ext_type )
611 {
612 case MBEDTLS_X509_EXT_BASIC_CONSTRAINTS:
613 /* Parse basic constraints */
614 if( ( ret = x509_get_basic_constraints( p, end_ext_octet,
615 &crt->ca_istrue, &crt->max_pathlen ) ) != 0 )
616 return( ret );
617 break;
618
619 case MBEDTLS_X509_EXT_KEY_USAGE:
620 /* Parse key usage */
621 if( ( ret = x509_get_key_usage( p, end_ext_octet,
622 &crt->key_usage ) ) != 0 )
623 return( ret );
624 break;
625
626 case MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE:
627 /* Parse extended key usage */
628 if( ( ret = x509_get_ext_key_usage( p, end_ext_octet,
629 &crt->ext_key_usage ) ) != 0 )
630 return( ret );
631 break;
632
633 case MBEDTLS_X509_EXT_SUBJECT_ALT_NAME:
634 /* Parse subject alt name */
635 if( ( ret = x509_get_subject_alt_name( p, end_ext_octet,
636 &crt->subject_alt_names ) ) != 0 )
637 return( ret );
638 break;
639
640 case MBEDTLS_X509_EXT_NS_CERT_TYPE:
641 /* Parse netscape certificate type */
642 if( ( ret = x509_get_ns_cert_type( p, end_ext_octet,
643 &crt->ns_cert_type ) ) != 0 )
644 return( ret );
645 break;
646
647 default:
648 return( MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE );
649 }
650 }
651
652 if( *p != end )
653 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
654 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
655
656 return( 0 );
657 }
658
659 /*
660 * Parse and fill a single X.509 certificate in DER format
661 */
x509_crt_parse_der_core(mbedtls_x509_crt * crt,const unsigned char * buf,size_t buflen)662 static int x509_crt_parse_der_core( mbedtls_x509_crt *crt, const unsigned char *buf,
663 size_t buflen )
664 {
665 int ret;
666 size_t len;
667 unsigned char *p, *end, *crt_end;
668 mbedtls_x509_buf sig_params1, sig_params2, sig_oid2;
669
670 memset( &sig_params1, 0, sizeof( mbedtls_x509_buf ) );
671 memset( &sig_params2, 0, sizeof( mbedtls_x509_buf ) );
672 memset( &sig_oid2, 0, sizeof( mbedtls_x509_buf ) );
673
674 /*
675 * Check for valid input
676 */
677 if( crt == NULL || buf == NULL )
678 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
679
680 // Use the original buffer until we figure out actual length
681 p = (unsigned char*) buf;
682 len = buflen;
683 end = p + len;
684
685 /*
686 * Certificate ::= SEQUENCE {
687 * tbsCertificate TBSCertificate,
688 * signatureAlgorithm AlgorithmIdentifier,
689 * signatureValue BIT STRING }
690 */
691 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
692 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
693 {
694 mbedtls_x509_crt_free( crt );
695 return( MBEDTLS_ERR_X509_INVALID_FORMAT );
696 }
697
698 if( len > (size_t) ( end - p ) )
699 {
700 mbedtls_x509_crt_free( crt );
701 return( MBEDTLS_ERR_X509_INVALID_FORMAT +
702 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
703 }
704 crt_end = p + len;
705
706 // Create and populate a new buffer for the raw field
707 crt->raw.len = crt_end - buf;
708 crt->raw.p = p = mbedtls_calloc( 1, crt->raw.len );
709 if( p == NULL )
710 return( MBEDTLS_ERR_X509_ALLOC_FAILED );
711
712 memcpy( p, buf, crt->raw.len );
713
714 // Direct pointers to the new buffer
715 p += crt->raw.len - len;
716 end = crt_end = p + len;
717
718 /*
719 * TBSCertificate ::= SEQUENCE {
720 */
721 crt->tbs.p = p;
722
723 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
724 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
725 {
726 mbedtls_x509_crt_free( crt );
727 return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
728 }
729
730 end = p + len;
731 crt->tbs.len = end - crt->tbs.p;
732
733 /*
734 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
735 *
736 * CertificateSerialNumber ::= INTEGER
737 *
738 * signature AlgorithmIdentifier
739 */
740 if( ( ret = x509_get_version( &p, end, &crt->version ) ) != 0 ||
741 ( ret = mbedtls_x509_get_serial( &p, end, &crt->serial ) ) != 0 ||
742 ( ret = mbedtls_x509_get_alg( &p, end, &crt->sig_oid,
743 &sig_params1 ) ) != 0 )
744 {
745 mbedtls_x509_crt_free( crt );
746 return( ret );
747 }
748
749 crt->version++;
750
751 if( crt->version > 3 )
752 {
753 mbedtls_x509_crt_free( crt );
754 return( MBEDTLS_ERR_X509_UNKNOWN_VERSION );
755 }
756
757 if( ( ret = mbedtls_x509_get_sig_alg( &crt->sig_oid, &sig_params1,
758 &crt->sig_md, &crt->sig_pk,
759 &crt->sig_opts ) ) != 0 )
760 {
761 mbedtls_x509_crt_free( crt );
762 return( ret );
763 }
764
765 /*
766 * issuer Name
767 */
768 crt->issuer_raw.p = p;
769
770 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
771 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
772 {
773 mbedtls_x509_crt_free( crt );
774 return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
775 }
776
777 if( ( ret = mbedtls_x509_get_name( &p, p + len, &crt->issuer ) ) != 0 )
778 {
779 mbedtls_x509_crt_free( crt );
780 return( ret );
781 }
782
783 crt->issuer_raw.len = p - crt->issuer_raw.p;
784
785 /*
786 * Validity ::= SEQUENCE {
787 * notBefore Time,
788 * notAfter Time }
789 *
790 */
791 if( ( ret = x509_get_dates( &p, end, &crt->valid_from,
792 &crt->valid_to ) ) != 0 )
793 {
794 mbedtls_x509_crt_free( crt );
795 return( ret );
796 }
797
798 /*
799 * subject Name
800 */
801 crt->subject_raw.p = p;
802
803 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
804 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
805 {
806 mbedtls_x509_crt_free( crt );
807 return( MBEDTLS_ERR_X509_INVALID_FORMAT + ret );
808 }
809
810 if( len && ( ret = mbedtls_x509_get_name( &p, p + len, &crt->subject ) ) != 0 )
811 {
812 mbedtls_x509_crt_free( crt );
813 return( ret );
814 }
815
816 crt->subject_raw.len = p - crt->subject_raw.p;
817
818 /*
819 * SubjectPublicKeyInfo
820 */
821 if( ( ret = mbedtls_pk_parse_subpubkey( &p, end, &crt->pk ) ) != 0 )
822 {
823 mbedtls_x509_crt_free( crt );
824 return( ret );
825 }
826
827 /*
828 * issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
829 * -- If present, version shall be v2 or v3
830 * subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
831 * -- If present, version shall be v2 or v3
832 * extensions [3] EXPLICIT Extensions OPTIONAL
833 * -- If present, version shall be v3
834 */
835 if( crt->version == 2 || crt->version == 3 )
836 {
837 ret = x509_get_uid( &p, end, &crt->issuer_id, 1 );
838 if( ret != 0 )
839 {
840 mbedtls_x509_crt_free( crt );
841 return( ret );
842 }
843 }
844
845 if( crt->version == 2 || crt->version == 3 )
846 {
847 ret = x509_get_uid( &p, end, &crt->subject_id, 2 );
848 if( ret != 0 )
849 {
850 mbedtls_x509_crt_free( crt );
851 return( ret );
852 }
853 }
854
855 #if !defined(MBEDTLS_X509_ALLOW_EXTENSIONS_NON_V3)
856 if( crt->version == 3 )
857 #endif
858 {
859 ret = x509_get_crt_ext( &p, end, crt );
860 if( ret != 0 )
861 {
862 mbedtls_x509_crt_free( crt );
863 return( ret );
864 }
865 }
866
867 if( p != end )
868 {
869 mbedtls_x509_crt_free( crt );
870 return( MBEDTLS_ERR_X509_INVALID_FORMAT +
871 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
872 }
873
874 end = crt_end;
875
876 /*
877 * }
878 * -- end of TBSCertificate
879 *
880 * signatureAlgorithm AlgorithmIdentifier,
881 * signatureValue BIT STRING
882 */
883 if( ( ret = mbedtls_x509_get_alg( &p, end, &sig_oid2, &sig_params2 ) ) != 0 )
884 {
885 mbedtls_x509_crt_free( crt );
886 return( ret );
887 }
888
889 if( crt->sig_oid.len != sig_oid2.len ||
890 memcmp( crt->sig_oid.p, sig_oid2.p, crt->sig_oid.len ) != 0 ||
891 sig_params1.len != sig_params2.len ||
892 ( sig_params1.len != 0 &&
893 memcmp( sig_params1.p, sig_params2.p, sig_params1.len ) != 0 ) )
894 {
895 mbedtls_x509_crt_free( crt );
896 return( MBEDTLS_ERR_X509_SIG_MISMATCH );
897 }
898
899 if( ( ret = mbedtls_x509_get_sig( &p, end, &crt->sig ) ) != 0 )
900 {
901 mbedtls_x509_crt_free( crt );
902 return( ret );
903 }
904
905 if( p != end )
906 {
907 mbedtls_x509_crt_free( crt );
908 return( MBEDTLS_ERR_X509_INVALID_FORMAT +
909 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
910 }
911
912 return( 0 );
913 }
914
915 /*
916 * Parse one X.509 certificate in DER format from a buffer and add them to a
917 * chained list
918 */
mbedtls_x509_crt_parse_der(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)919 int mbedtls_x509_crt_parse_der( mbedtls_x509_crt *chain, const unsigned char *buf,
920 size_t buflen )
921 {
922 int ret;
923 mbedtls_x509_crt *crt = chain, *prev = NULL;
924
925 /*
926 * Check for valid input
927 */
928 if( crt == NULL || buf == NULL )
929 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
930
931 while( crt->version != 0 && crt->next != NULL )
932 {
933 prev = crt;
934 crt = crt->next;
935 }
936
937 /*
938 * Add new certificate on the end of the chain if needed.
939 */
940 if( crt->version != 0 && crt->next == NULL )
941 {
942 crt->next = mbedtls_calloc( 1, sizeof( mbedtls_x509_crt ) );
943
944 if( crt->next == NULL )
945 return( MBEDTLS_ERR_X509_ALLOC_FAILED );
946
947 prev = crt;
948 mbedtls_x509_crt_init( crt->next );
949 crt = crt->next;
950 }
951
952 if( ( ret = x509_crt_parse_der_core( crt, buf, buflen ) ) != 0 )
953 {
954 if( prev )
955 prev->next = NULL;
956
957 if( crt != chain )
958 mbedtls_free( crt );
959
960 return( ret );
961 }
962
963 return( 0 );
964 }
965
966 /*
967 * Parse one or more PEM certificates from a buffer and add them to the chained
968 * list
969 */
mbedtls_x509_crt_parse(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)970 int mbedtls_x509_crt_parse( mbedtls_x509_crt *chain, const unsigned char *buf, size_t buflen )
971 {
972 int success = 0, first_error = 0, total_failed = 0;
973 #if defined(MBEDTLS_PEM_PARSE_C)
974 int buf_format = MBEDTLS_X509_FORMAT_DER;
975 #endif
976
977 /*
978 * Check for valid input
979 */
980 if( chain == NULL || buf == NULL )
981 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
982
983 /*
984 * Determine buffer content. Buffer contains either one DER certificate or
985 * one or more PEM certificates.
986 */
987 #if defined(MBEDTLS_PEM_PARSE_C)
988 if( buflen != 0 && buf[buflen - 1] == '\0' &&
989 strstr( (const char *) buf, "-----BEGIN CERTIFICATE-----" ) != NULL )
990 {
991 buf_format = MBEDTLS_X509_FORMAT_PEM;
992 }
993
994 if( buf_format == MBEDTLS_X509_FORMAT_DER )
995 return mbedtls_x509_crt_parse_der( chain, buf, buflen );
996 #else
997 return mbedtls_x509_crt_parse_der( chain, buf, buflen );
998 #endif
999
1000 #if defined(MBEDTLS_PEM_PARSE_C)
1001 if( buf_format == MBEDTLS_X509_FORMAT_PEM )
1002 {
1003 int ret;
1004 mbedtls_pem_context pem;
1005
1006 /* 1 rather than 0 since the terminating NULL byte is counted in */
1007 while( buflen > 1 )
1008 {
1009 size_t use_len;
1010 mbedtls_pem_init( &pem );
1011
1012 /* If we get there, we know the string is null-terminated */
1013 ret = mbedtls_pem_read_buffer( &pem,
1014 "-----BEGIN CERTIFICATE-----",
1015 "-----END CERTIFICATE-----",
1016 buf, NULL, 0, &use_len );
1017
1018 if( ret == 0 )
1019 {
1020 /*
1021 * Was PEM encoded
1022 */
1023 buflen -= use_len;
1024 buf += use_len;
1025 }
1026 else if( ret == MBEDTLS_ERR_PEM_BAD_INPUT_DATA )
1027 {
1028 return( ret );
1029 }
1030 else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
1031 {
1032 mbedtls_pem_free( &pem );
1033
1034 /*
1035 * PEM header and footer were found
1036 */
1037 buflen -= use_len;
1038 buf += use_len;
1039
1040 if( first_error == 0 )
1041 first_error = ret;
1042
1043 total_failed++;
1044 continue;
1045 }
1046 else
1047 break;
1048
1049 ret = mbedtls_x509_crt_parse_der( chain, pem.buf, pem.buflen );
1050
1051 mbedtls_pem_free( &pem );
1052
1053 if( ret != 0 )
1054 {
1055 /*
1056 * Quit parsing on a memory error
1057 */
1058 if( ret == MBEDTLS_ERR_X509_ALLOC_FAILED )
1059 return( ret );
1060
1061 if( first_error == 0 )
1062 first_error = ret;
1063
1064 total_failed++;
1065 continue;
1066 }
1067
1068 success = 1;
1069 }
1070 }
1071
1072 if( success )
1073 return( total_failed );
1074 else if( first_error )
1075 return( first_error );
1076 else
1077 return( MBEDTLS_ERR_X509_CERT_UNKNOWN_FORMAT );
1078 #endif /* MBEDTLS_PEM_PARSE_C */
1079 }
1080
1081 #if defined(MBEDTLS_FS_IO)
1082 /*
1083 * Load one or more certificates and add them to the chained list
1084 */
mbedtls_x509_crt_parse_file(mbedtls_x509_crt * chain,const char * path)1085 int mbedtls_x509_crt_parse_file( mbedtls_x509_crt *chain, const char *path )
1086 {
1087 int ret;
1088 size_t n;
1089 unsigned char *buf;
1090
1091 if( ( ret = mbedtls_pk_load_file( path, &buf, &n ) ) != 0 )
1092 return( ret );
1093
1094 ret = mbedtls_x509_crt_parse( chain, buf, n );
1095
1096 mbedtls_zeroize( buf, n );
1097 mbedtls_free( buf );
1098
1099 return( ret );
1100 }
1101
mbedtls_x509_crt_parse_path(mbedtls_x509_crt * chain,const char * path)1102 int mbedtls_x509_crt_parse_path( mbedtls_x509_crt *chain, const char *path )
1103 {
1104 int ret = 0;
1105 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
1106 int w_ret;
1107 WCHAR szDir[MAX_PATH];
1108 char filename[MAX_PATH];
1109 char *p;
1110 size_t len = strlen( path );
1111
1112 WIN32_FIND_DATAW file_data;
1113 HANDLE hFind;
1114
1115 if( len > MAX_PATH - 3 )
1116 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1117
1118 memset( szDir, 0, sizeof(szDir) );
1119 memset( filename, 0, MAX_PATH );
1120 memcpy( filename, path, len );
1121 filename[len++] = '\\';
1122 p = filename + len;
1123 filename[len++] = '*';
1124
1125 w_ret = MultiByteToWideChar( CP_ACP, 0, filename, len, szDir,
1126 MAX_PATH - 3 );
1127 if( w_ret == 0 )
1128 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1129
1130 hFind = FindFirstFileW( szDir, &file_data );
1131 if( hFind == INVALID_HANDLE_VALUE )
1132 return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
1133
1134 len = MAX_PATH - len;
1135 do
1136 {
1137 memset( p, 0, len );
1138
1139 if( file_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY )
1140 continue;
1141
1142 w_ret = WideCharToMultiByte( CP_ACP, 0, file_data.cFileName,
1143 lstrlenW( file_data.cFileName ),
1144 p, (int) len - 1,
1145 NULL, NULL );
1146 if( w_ret == 0 )
1147 return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
1148
1149 w_ret = mbedtls_x509_crt_parse_file( chain, filename );
1150 if( w_ret < 0 )
1151 ret++;
1152 else
1153 ret += w_ret;
1154 }
1155 while( FindNextFileW( hFind, &file_data ) != 0 );
1156
1157 if( GetLastError() != ERROR_NO_MORE_FILES )
1158 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1159
1160 FindClose( hFind );
1161 #else /* _WIN32 */
1162 int t_ret;
1163 int snp_ret;
1164 struct stat sb;
1165 struct dirent *entry;
1166 char entry_name[MBEDTLS_X509_MAX_FILE_PATH_LEN];
1167 DIR *dir = opendir( path );
1168
1169 if( dir == NULL )
1170 return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
1171
1172 #if defined(MBEDTLS_THREADING_PTHREAD)
1173 if( ( ret = mbedtls_mutex_lock( &mbedtls_threading_readdir_mutex ) ) != 0 )
1174 {
1175 closedir( dir );
1176 return( ret );
1177 }
1178 #endif
1179
1180 while( ( entry = readdir( dir ) ) != NULL )
1181 {
1182 snp_ret = mbedtls_snprintf( entry_name, sizeof entry_name,
1183 "%s/%s", path, entry->d_name );
1184
1185 if( snp_ret < 0 || (size_t)snp_ret >= sizeof entry_name )
1186 {
1187 ret = MBEDTLS_ERR_X509_BUFFER_TOO_SMALL;
1188 goto cleanup;
1189 }
1190 else if( stat( entry_name, &sb ) == -1 )
1191 {
1192 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1193 goto cleanup;
1194 }
1195
1196 if( !S_ISREG( sb.st_mode ) )
1197 continue;
1198
1199 // Ignore parse errors
1200 //
1201 t_ret = mbedtls_x509_crt_parse_file( chain, entry_name );
1202 if( t_ret < 0 )
1203 ret++;
1204 else
1205 ret += t_ret;
1206 }
1207
1208 cleanup:
1209 closedir( dir );
1210
1211 #if defined(MBEDTLS_THREADING_PTHREAD)
1212 if( mbedtls_mutex_unlock( &mbedtls_threading_readdir_mutex ) != 0 )
1213 ret = MBEDTLS_ERR_THREADING_MUTEX_ERROR;
1214 #endif
1215
1216 #endif /* _WIN32 */
1217
1218 return( ret );
1219 }
1220 #endif /* MBEDTLS_FS_IO */
1221
x509_info_subject_alt_name(char ** buf,size_t * size,const mbedtls_x509_sequence * subject_alt_name)1222 static int x509_info_subject_alt_name( char **buf, size_t *size,
1223 const mbedtls_x509_sequence *subject_alt_name )
1224 {
1225 size_t i;
1226 size_t n = *size;
1227 char *p = *buf;
1228 const mbedtls_x509_sequence *cur = subject_alt_name;
1229 const char *sep = "";
1230 size_t sep_len = 0;
1231
1232 while( cur != NULL )
1233 {
1234 if( cur->buf.len + sep_len >= n )
1235 {
1236 *p = '\0';
1237 return( MBEDTLS_ERR_X509_BUFFER_TOO_SMALL );
1238 }
1239
1240 n -= cur->buf.len + sep_len;
1241 for( i = 0; i < sep_len; i++ )
1242 *p++ = sep[i];
1243 for( i = 0; i < cur->buf.len; i++ )
1244 *p++ = cur->buf.p[i];
1245
1246 sep = ", ";
1247 sep_len = 2;
1248
1249 cur = cur->next;
1250 }
1251
1252 *p = '\0';
1253
1254 *size = n;
1255 *buf = p;
1256
1257 return( 0 );
1258 }
1259
1260 #define PRINT_ITEM(i) \
1261 { \
1262 ret = mbedtls_snprintf( p, n, "%s" i, sep ); \
1263 MBEDTLS_X509_SAFE_SNPRINTF; \
1264 sep = ", "; \
1265 }
1266
1267 #define CERT_TYPE(type,name) \
1268 if( ns_cert_type & type ) \
1269 PRINT_ITEM( name );
1270
x509_info_cert_type(char ** buf,size_t * size,unsigned char ns_cert_type)1271 static int x509_info_cert_type( char **buf, size_t *size,
1272 unsigned char ns_cert_type )
1273 {
1274 int ret;
1275 size_t n = *size;
1276 char *p = *buf;
1277 const char *sep = "";
1278
1279 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_CLIENT, "SSL Client" );
1280 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER, "SSL Server" );
1281 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_EMAIL, "Email" );
1282 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING, "Object Signing" );
1283 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_RESERVED, "Reserved" );
1284 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_CA, "SSL CA" );
1285 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_EMAIL_CA, "Email CA" );
1286 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING_CA, "Object Signing CA" );
1287
1288 *size = n;
1289 *buf = p;
1290
1291 return( 0 );
1292 }
1293
1294 #define KEY_USAGE(code,name) \
1295 if( key_usage & code ) \
1296 PRINT_ITEM( name );
1297
x509_info_key_usage(char ** buf,size_t * size,unsigned int key_usage)1298 static int x509_info_key_usage( char **buf, size_t *size,
1299 unsigned int key_usage )
1300 {
1301 int ret;
1302 size_t n = *size;
1303 char *p = *buf;
1304 const char *sep = "";
1305
1306 KEY_USAGE( MBEDTLS_X509_KU_DIGITAL_SIGNATURE, "Digital Signature" );
1307 KEY_USAGE( MBEDTLS_X509_KU_NON_REPUDIATION, "Non Repudiation" );
1308 KEY_USAGE( MBEDTLS_X509_KU_KEY_ENCIPHERMENT, "Key Encipherment" );
1309 KEY_USAGE( MBEDTLS_X509_KU_DATA_ENCIPHERMENT, "Data Encipherment" );
1310 KEY_USAGE( MBEDTLS_X509_KU_KEY_AGREEMENT, "Key Agreement" );
1311 KEY_USAGE( MBEDTLS_X509_KU_KEY_CERT_SIGN, "Key Cert Sign" );
1312 KEY_USAGE( MBEDTLS_X509_KU_CRL_SIGN, "CRL Sign" );
1313 KEY_USAGE( MBEDTLS_X509_KU_ENCIPHER_ONLY, "Encipher Only" );
1314 KEY_USAGE( MBEDTLS_X509_KU_DECIPHER_ONLY, "Decipher Only" );
1315
1316 *size = n;
1317 *buf = p;
1318
1319 return( 0 );
1320 }
1321
x509_info_ext_key_usage(char ** buf,size_t * size,const mbedtls_x509_sequence * extended_key_usage)1322 static int x509_info_ext_key_usage( char **buf, size_t *size,
1323 const mbedtls_x509_sequence *extended_key_usage )
1324 {
1325 int ret;
1326 const char *desc;
1327 size_t n = *size;
1328 char *p = *buf;
1329 const mbedtls_x509_sequence *cur = extended_key_usage;
1330 const char *sep = "";
1331
1332 while( cur != NULL )
1333 {
1334 if( mbedtls_oid_get_extended_key_usage( &cur->buf, &desc ) != 0 )
1335 desc = "???";
1336
1337 ret = mbedtls_snprintf( p, n, "%s%s", sep, desc );
1338 MBEDTLS_X509_SAFE_SNPRINTF;
1339
1340 sep = ", ";
1341
1342 cur = cur->next;
1343 }
1344
1345 *size = n;
1346 *buf = p;
1347
1348 return( 0 );
1349 }
1350
1351 /*
1352 * Return an informational string about the certificate.
1353 */
1354 #define BEFORE_COLON 18
1355 #define BC "18"
mbedtls_x509_crt_info(char * buf,size_t size,const char * prefix,const mbedtls_x509_crt * crt)1356 int mbedtls_x509_crt_info( char *buf, size_t size, const char *prefix,
1357 const mbedtls_x509_crt *crt )
1358 {
1359 int ret;
1360 size_t n;
1361 char *p;
1362 char key_size_str[BEFORE_COLON];
1363
1364 p = buf;
1365 n = size;
1366
1367 if( NULL == crt )
1368 {
1369 ret = mbedtls_snprintf( p, n, "\nCertificate is uninitialised!\n" );
1370 MBEDTLS_X509_SAFE_SNPRINTF;
1371
1372 return( (int) ( size - n ) );
1373 }
1374
1375 ret = mbedtls_snprintf( p, n, "%scert. version : %d\n",
1376 prefix, crt->version );
1377 MBEDTLS_X509_SAFE_SNPRINTF;
1378 ret = mbedtls_snprintf( p, n, "%sserial number : ",
1379 prefix );
1380 MBEDTLS_X509_SAFE_SNPRINTF;
1381
1382 ret = mbedtls_x509_serial_gets( p, n, &crt->serial );
1383 MBEDTLS_X509_SAFE_SNPRINTF;
1384
1385 ret = mbedtls_snprintf( p, n, "\n%sissuer name : ", prefix );
1386 MBEDTLS_X509_SAFE_SNPRINTF;
1387 ret = mbedtls_x509_dn_gets( p, n, &crt->issuer );
1388 MBEDTLS_X509_SAFE_SNPRINTF;
1389
1390 ret = mbedtls_snprintf( p, n, "\n%ssubject name : ", prefix );
1391 MBEDTLS_X509_SAFE_SNPRINTF;
1392 ret = mbedtls_x509_dn_gets( p, n, &crt->subject );
1393 MBEDTLS_X509_SAFE_SNPRINTF;
1394
1395 ret = mbedtls_snprintf( p, n, "\n%sissued on : " \
1396 "%04d-%02d-%02d %02d:%02d:%02d", prefix,
1397 crt->valid_from.year, crt->valid_from.mon,
1398 crt->valid_from.day, crt->valid_from.hour,
1399 crt->valid_from.min, crt->valid_from.sec );
1400 MBEDTLS_X509_SAFE_SNPRINTF;
1401
1402 ret = mbedtls_snprintf( p, n, "\n%sexpires on : " \
1403 "%04d-%02d-%02d %02d:%02d:%02d", prefix,
1404 crt->valid_to.year, crt->valid_to.mon,
1405 crt->valid_to.day, crt->valid_to.hour,
1406 crt->valid_to.min, crt->valid_to.sec );
1407 MBEDTLS_X509_SAFE_SNPRINTF;
1408
1409 ret = mbedtls_snprintf( p, n, "\n%ssigned using : ", prefix );
1410 MBEDTLS_X509_SAFE_SNPRINTF;
1411
1412 ret = mbedtls_x509_sig_alg_gets( p, n, &crt->sig_oid, crt->sig_pk,
1413 crt->sig_md, crt->sig_opts );
1414 MBEDTLS_X509_SAFE_SNPRINTF;
1415
1416 /* Key size */
1417 if( ( ret = mbedtls_x509_key_size_helper( key_size_str, BEFORE_COLON,
1418 mbedtls_pk_get_name( &crt->pk ) ) ) != 0 )
1419 {
1420 return( ret );
1421 }
1422
1423 ret = mbedtls_snprintf( p, n, "\n%s%-" BC "s: %d bits", prefix, key_size_str,
1424 (int) mbedtls_pk_get_bitlen( &crt->pk ) );
1425 MBEDTLS_X509_SAFE_SNPRINTF;
1426
1427 /*
1428 * Optional extensions
1429 */
1430
1431 if( crt->ext_types & MBEDTLS_X509_EXT_BASIC_CONSTRAINTS )
1432 {
1433 ret = mbedtls_snprintf( p, n, "\n%sbasic constraints : CA=%s", prefix,
1434 crt->ca_istrue ? "true" : "false" );
1435 MBEDTLS_X509_SAFE_SNPRINTF;
1436
1437 if( crt->max_pathlen > 0 )
1438 {
1439 ret = mbedtls_snprintf( p, n, ", max_pathlen=%d", crt->max_pathlen - 1 );
1440 MBEDTLS_X509_SAFE_SNPRINTF;
1441 }
1442 }
1443
1444 if( crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME )
1445 {
1446 ret = mbedtls_snprintf( p, n, "\n%ssubject alt name : ", prefix );
1447 MBEDTLS_X509_SAFE_SNPRINTF;
1448
1449 if( ( ret = x509_info_subject_alt_name( &p, &n,
1450 &crt->subject_alt_names ) ) != 0 )
1451 return( ret );
1452 }
1453
1454 if( crt->ext_types & MBEDTLS_X509_EXT_NS_CERT_TYPE )
1455 {
1456 ret = mbedtls_snprintf( p, n, "\n%scert. type : ", prefix );
1457 MBEDTLS_X509_SAFE_SNPRINTF;
1458
1459 if( ( ret = x509_info_cert_type( &p, &n, crt->ns_cert_type ) ) != 0 )
1460 return( ret );
1461 }
1462
1463 if( crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE )
1464 {
1465 ret = mbedtls_snprintf( p, n, "\n%skey usage : ", prefix );
1466 MBEDTLS_X509_SAFE_SNPRINTF;
1467
1468 if( ( ret = x509_info_key_usage( &p, &n, crt->key_usage ) ) != 0 )
1469 return( ret );
1470 }
1471
1472 if( crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE )
1473 {
1474 ret = mbedtls_snprintf( p, n, "\n%sext key usage : ", prefix );
1475 MBEDTLS_X509_SAFE_SNPRINTF;
1476
1477 if( ( ret = x509_info_ext_key_usage( &p, &n,
1478 &crt->ext_key_usage ) ) != 0 )
1479 return( ret );
1480 }
1481
1482 ret = mbedtls_snprintf( p, n, "\n" );
1483 MBEDTLS_X509_SAFE_SNPRINTF;
1484
1485 return( (int) ( size - n ) );
1486 }
1487
1488 struct x509_crt_verify_string {
1489 int code;
1490 const char *string;
1491 };
1492
1493 static const struct x509_crt_verify_string x509_crt_verify_strings[] = {
1494 { MBEDTLS_X509_BADCERT_EXPIRED, "The certificate validity has expired" },
1495 { MBEDTLS_X509_BADCERT_REVOKED, "The certificate has been revoked (is on a CRL)" },
1496 { MBEDTLS_X509_BADCERT_CN_MISMATCH, "The certificate Common Name (CN) does not match with the expected CN" },
1497 { MBEDTLS_X509_BADCERT_NOT_TRUSTED, "The certificate is not correctly signed by the trusted CA" },
1498 { MBEDTLS_X509_BADCRL_NOT_TRUSTED, "The CRL is not correctly signed by the trusted CA" },
1499 { MBEDTLS_X509_BADCRL_EXPIRED, "The CRL is expired" },
1500 { MBEDTLS_X509_BADCERT_MISSING, "Certificate was missing" },
1501 { MBEDTLS_X509_BADCERT_SKIP_VERIFY, "Certificate verification was skipped" },
1502 { MBEDTLS_X509_BADCERT_OTHER, "Other reason (can be used by verify callback)" },
1503 { MBEDTLS_X509_BADCERT_FUTURE, "The certificate validity starts in the future" },
1504 { MBEDTLS_X509_BADCRL_FUTURE, "The CRL is from the future" },
1505 { MBEDTLS_X509_BADCERT_KEY_USAGE, "Usage does not match the keyUsage extension" },
1506 { MBEDTLS_X509_BADCERT_EXT_KEY_USAGE, "Usage does not match the extendedKeyUsage extension" },
1507 { MBEDTLS_X509_BADCERT_NS_CERT_TYPE, "Usage does not match the nsCertType extension" },
1508 { MBEDTLS_X509_BADCERT_BAD_MD, "The certificate is signed with an unacceptable hash." },
1509 { MBEDTLS_X509_BADCERT_BAD_PK, "The certificate is signed with an unacceptable PK alg (eg RSA vs ECDSA)." },
1510 { MBEDTLS_X509_BADCERT_BAD_KEY, "The certificate is signed with an unacceptable key (eg bad curve, RSA too short)." },
1511 { MBEDTLS_X509_BADCRL_BAD_MD, "The CRL is signed with an unacceptable hash." },
1512 { MBEDTLS_X509_BADCRL_BAD_PK, "The CRL is signed with an unacceptable PK alg (eg RSA vs ECDSA)." },
1513 { MBEDTLS_X509_BADCRL_BAD_KEY, "The CRL is signed with an unacceptable key (eg bad curve, RSA too short)." },
1514 { 0, NULL }
1515 };
1516
mbedtls_x509_crt_verify_info(char * buf,size_t size,const char * prefix,uint32_t flags)1517 int mbedtls_x509_crt_verify_info( char *buf, size_t size, const char *prefix,
1518 uint32_t flags )
1519 {
1520 int ret;
1521 const struct x509_crt_verify_string *cur;
1522 char *p = buf;
1523 size_t n = size;
1524
1525 for( cur = x509_crt_verify_strings; cur->string != NULL ; cur++ )
1526 {
1527 if( ( flags & cur->code ) == 0 )
1528 continue;
1529
1530 ret = mbedtls_snprintf( p, n, "%s%s\n", prefix, cur->string );
1531 MBEDTLS_X509_SAFE_SNPRINTF;
1532 flags ^= cur->code;
1533 }
1534
1535 if( flags != 0 )
1536 {
1537 ret = mbedtls_snprintf( p, n, "%sUnknown reason "
1538 "(this should not happen)\n", prefix );
1539 MBEDTLS_X509_SAFE_SNPRINTF;
1540 }
1541
1542 return( (int) ( size - n ) );
1543 }
1544
1545 #if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
mbedtls_x509_crt_check_key_usage(const mbedtls_x509_crt * crt,unsigned int usage)1546 int mbedtls_x509_crt_check_key_usage( const mbedtls_x509_crt *crt,
1547 unsigned int usage )
1548 {
1549 unsigned int usage_must, usage_may;
1550 unsigned int may_mask = MBEDTLS_X509_KU_ENCIPHER_ONLY
1551 | MBEDTLS_X509_KU_DECIPHER_ONLY;
1552
1553 if( ( crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE ) == 0 )
1554 return( 0 );
1555
1556 usage_must = usage & ~may_mask;
1557
1558 if( ( ( crt->key_usage & ~may_mask ) & usage_must ) != usage_must )
1559 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1560
1561 usage_may = usage & may_mask;
1562
1563 if( ( ( crt->key_usage & may_mask ) | usage_may ) != usage_may )
1564 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1565
1566 return( 0 );
1567 }
1568 #endif
1569
1570 #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)1571 int mbedtls_x509_crt_check_extended_key_usage( const mbedtls_x509_crt *crt,
1572 const char *usage_oid,
1573 size_t usage_len )
1574 {
1575 const mbedtls_x509_sequence *cur;
1576
1577 /* Extension is not mandatory, absent means no restriction */
1578 if( ( crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE ) == 0 )
1579 return( 0 );
1580
1581 /*
1582 * Look for the requested usage (or wildcard ANY) in our list
1583 */
1584 for( cur = &crt->ext_key_usage; cur != NULL; cur = cur->next )
1585 {
1586 const mbedtls_x509_buf *cur_oid = &cur->buf;
1587
1588 if( cur_oid->len == usage_len &&
1589 memcmp( cur_oid->p, usage_oid, usage_len ) == 0 )
1590 {
1591 return( 0 );
1592 }
1593
1594 if( MBEDTLS_OID_CMP( MBEDTLS_OID_ANY_EXTENDED_KEY_USAGE, cur_oid ) == 0 )
1595 return( 0 );
1596 }
1597
1598 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1599 }
1600 #endif /* MBEDTLS_X509_CHECK_EXTENDED_KEY_USAGE */
1601
1602 #if defined(MBEDTLS_X509_CRL_PARSE_C)
1603 /*
1604 * Return 1 if the certificate is revoked, or 0 otherwise.
1605 */
mbedtls_x509_crt_is_revoked(const mbedtls_x509_crt * crt,const mbedtls_x509_crl * crl)1606 int mbedtls_x509_crt_is_revoked( const mbedtls_x509_crt *crt, const mbedtls_x509_crl *crl )
1607 {
1608 const mbedtls_x509_crl_entry *cur = &crl->entry;
1609
1610 while( cur != NULL && cur->serial.len != 0 )
1611 {
1612 if( crt->serial.len == cur->serial.len &&
1613 memcmp( crt->serial.p, cur->serial.p, crt->serial.len ) == 0 )
1614 {
1615 if( mbedtls_x509_time_is_past( &cur->revocation_date ) )
1616 return( 1 );
1617 }
1618
1619 cur = cur->next;
1620 }
1621
1622 return( 0 );
1623 }
1624
1625 /*
1626 * Check that the given certificate is not revoked according to the CRL.
1627 * Skip validation is no CRL for the given CA is present.
1628 */
x509_crt_verifycrl(mbedtls_x509_crt * crt,mbedtls_x509_crt * ca,mbedtls_x509_crl * crl_list,const mbedtls_x509_crt_profile * profile)1629 static int x509_crt_verifycrl( mbedtls_x509_crt *crt, mbedtls_x509_crt *ca,
1630 mbedtls_x509_crl *crl_list,
1631 const mbedtls_x509_crt_profile *profile )
1632 {
1633 int flags = 0;
1634 unsigned char hash[MBEDTLS_MD_MAX_SIZE];
1635 const mbedtls_md_info_t *md_info;
1636
1637 if( ca == NULL )
1638 return( flags );
1639
1640 while( crl_list != NULL )
1641 {
1642 if( crl_list->version == 0 ||
1643 crl_list->issuer_raw.len != ca->subject_raw.len ||
1644 memcmp( crl_list->issuer_raw.p, ca->subject_raw.p,
1645 crl_list->issuer_raw.len ) != 0 )
1646 {
1647 crl_list = crl_list->next;
1648 continue;
1649 }
1650
1651 /*
1652 * Check if the CA is configured to sign CRLs
1653 */
1654 #if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
1655 if( mbedtls_x509_crt_check_key_usage( ca, MBEDTLS_X509_KU_CRL_SIGN ) != 0 )
1656 {
1657 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
1658 break;
1659 }
1660 #endif
1661
1662 /*
1663 * Check if CRL is correctly signed by the trusted CA
1664 */
1665 if( x509_profile_check_md_alg( profile, crl_list->sig_md ) != 0 )
1666 flags |= MBEDTLS_X509_BADCRL_BAD_MD;
1667
1668 if( x509_profile_check_pk_alg( profile, crl_list->sig_pk ) != 0 )
1669 flags |= MBEDTLS_X509_BADCRL_BAD_PK;
1670
1671 md_info = mbedtls_md_info_from_type( crl_list->sig_md );
1672 if( md_info == NULL )
1673 {
1674 /*
1675 * Cannot check 'unknown' hash
1676 */
1677 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
1678 break;
1679 }
1680
1681 mbedtls_md( md_info, crl_list->tbs.p, crl_list->tbs.len, hash );
1682
1683 if( x509_profile_check_key( profile, crl_list->sig_pk, &ca->pk ) != 0 )
1684 flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
1685
1686 if( mbedtls_pk_verify_ext( crl_list->sig_pk, crl_list->sig_opts, &ca->pk,
1687 crl_list->sig_md, hash, mbedtls_md_get_size( md_info ),
1688 crl_list->sig.p, crl_list->sig.len ) != 0 )
1689 {
1690 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
1691 break;
1692 }
1693
1694 /*
1695 * Check for validity of CRL (Do not drop out)
1696 */
1697 if( mbedtls_x509_time_is_past( &crl_list->next_update ) )
1698 flags |= MBEDTLS_X509_BADCRL_EXPIRED;
1699
1700 if( mbedtls_x509_time_is_future( &crl_list->this_update ) )
1701 flags |= MBEDTLS_X509_BADCRL_FUTURE;
1702
1703 /*
1704 * Check if certificate is revoked
1705 */
1706 if( mbedtls_x509_crt_is_revoked( crt, crl_list ) )
1707 {
1708 flags |= MBEDTLS_X509_BADCERT_REVOKED;
1709 break;
1710 }
1711
1712 crl_list = crl_list->next;
1713 }
1714
1715 return( flags );
1716 }
1717 #endif /* MBEDTLS_X509_CRL_PARSE_C */
1718
1719 /*
1720 * Like memcmp, but case-insensitive and always returns -1 if different
1721 */
x509_memcasecmp(const void * s1,const void * s2,size_t len)1722 static int x509_memcasecmp( const void *s1, const void *s2, size_t len )
1723 {
1724 size_t i;
1725 unsigned char diff;
1726 const unsigned char *n1 = s1, *n2 = s2;
1727
1728 for( i = 0; i < len; i++ )
1729 {
1730 diff = n1[i] ^ n2[i];
1731
1732 if( diff == 0 )
1733 continue;
1734
1735 if( diff == 32 &&
1736 ( ( n1[i] >= 'a' && n1[i] <= 'z' ) ||
1737 ( n1[i] >= 'A' && n1[i] <= 'Z' ) ) )
1738 {
1739 continue;
1740 }
1741
1742 return( -1 );
1743 }
1744
1745 return( 0 );
1746 }
1747
1748 /*
1749 * Return 0 if name matches wildcard, -1 otherwise
1750 */
x509_check_wildcard(const char * cn,mbedtls_x509_buf * name)1751 static int x509_check_wildcard( const char *cn, mbedtls_x509_buf *name )
1752 {
1753 size_t i;
1754 size_t cn_idx = 0, cn_len = strlen( cn );
1755
1756 if( name->len < 3 || name->p[0] != '*' || name->p[1] != '.' )
1757 return( 0 );
1758
1759 for( i = 0; i < cn_len; ++i )
1760 {
1761 if( cn[i] == '.' )
1762 {
1763 cn_idx = i;
1764 break;
1765 }
1766 }
1767
1768 if( cn_idx == 0 )
1769 return( -1 );
1770
1771 if( cn_len - cn_idx == name->len - 1 &&
1772 x509_memcasecmp( name->p + 1, cn + cn_idx, name->len - 1 ) == 0 )
1773 {
1774 return( 0 );
1775 }
1776
1777 return( -1 );
1778 }
1779
1780 /*
1781 * Compare two X.509 strings, case-insensitive, and allowing for some encoding
1782 * variations (but not all).
1783 *
1784 * Return 0 if equal, -1 otherwise.
1785 */
x509_string_cmp(const mbedtls_x509_buf * a,const mbedtls_x509_buf * b)1786 static int x509_string_cmp( const mbedtls_x509_buf *a, const mbedtls_x509_buf *b )
1787 {
1788 if( a->tag == b->tag &&
1789 a->len == b->len &&
1790 memcmp( a->p, b->p, b->len ) == 0 )
1791 {
1792 return( 0 );
1793 }
1794
1795 if( ( a->tag == MBEDTLS_ASN1_UTF8_STRING || a->tag == MBEDTLS_ASN1_PRINTABLE_STRING ) &&
1796 ( b->tag == MBEDTLS_ASN1_UTF8_STRING || b->tag == MBEDTLS_ASN1_PRINTABLE_STRING ) &&
1797 a->len == b->len &&
1798 x509_memcasecmp( a->p, b->p, b->len ) == 0 )
1799 {
1800 return( 0 );
1801 }
1802
1803 return( -1 );
1804 }
1805
1806 /*
1807 * Compare two X.509 Names (aka rdnSequence).
1808 *
1809 * See RFC 5280 section 7.1, though we don't implement the whole algorithm:
1810 * we sometimes return unequal when the full algorithm would return equal,
1811 * but never the other way. (In particular, we don't do Unicode normalisation
1812 * or space folding.)
1813 *
1814 * Return 0 if equal, -1 otherwise.
1815 */
x509_name_cmp(const mbedtls_x509_name * a,const mbedtls_x509_name * b)1816 static int x509_name_cmp( const mbedtls_x509_name *a, const mbedtls_x509_name *b )
1817 {
1818 /* Avoid recursion, it might not be optimised by the compiler */
1819 while( a != NULL || b != NULL )
1820 {
1821 if( a == NULL || b == NULL )
1822 return( -1 );
1823
1824 /* type */
1825 if( a->oid.tag != b->oid.tag ||
1826 a->oid.len != b->oid.len ||
1827 memcmp( a->oid.p, b->oid.p, b->oid.len ) != 0 )
1828 {
1829 return( -1 );
1830 }
1831
1832 /* value */
1833 if( x509_string_cmp( &a->val, &b->val ) != 0 )
1834 return( -1 );
1835
1836 /* structure of the list of sets */
1837 if( a->next_merged != b->next_merged )
1838 return( -1 );
1839
1840 a = a->next;
1841 b = b->next;
1842 }
1843
1844 /* a == NULL == b */
1845 return( 0 );
1846 }
1847
1848 /*
1849 * Check if 'parent' is a suitable parent (signing CA) for 'child'.
1850 * Return 0 if yes, -1 if not.
1851 *
1852 * top means parent is a locally-trusted certificate
1853 * bottom means child is the end entity cert
1854 */
x509_crt_check_parent(const mbedtls_x509_crt * child,const mbedtls_x509_crt * parent,int top,int bottom)1855 static int x509_crt_check_parent( const mbedtls_x509_crt *child,
1856 const mbedtls_x509_crt *parent,
1857 int top, int bottom )
1858 {
1859 int need_ca_bit;
1860
1861 /* Parent must be the issuer */
1862 if( x509_name_cmp( &child->issuer, &parent->subject ) != 0 )
1863 return( -1 );
1864
1865 /* Parent must have the basicConstraints CA bit set as a general rule */
1866 need_ca_bit = 1;
1867
1868 /* Exception: v1/v2 certificates that are locally trusted. */
1869 if( top && parent->version < 3 )
1870 need_ca_bit = 0;
1871
1872 /* Exception: self-signed end-entity certs that are locally trusted. */
1873 if( top && bottom &&
1874 child->raw.len == parent->raw.len &&
1875 memcmp( child->raw.p, parent->raw.p, child->raw.len ) == 0 )
1876 {
1877 need_ca_bit = 0;
1878 }
1879
1880 if( need_ca_bit && ! parent->ca_istrue )
1881 return( -1 );
1882
1883 #if defined(MBEDTLS_X509_CHECK_KEY_USAGE)
1884 if( need_ca_bit &&
1885 mbedtls_x509_crt_check_key_usage( parent, MBEDTLS_X509_KU_KEY_CERT_SIGN ) != 0 )
1886 {
1887 return( -1 );
1888 }
1889 #endif
1890
1891 return( 0 );
1892 }
1893
x509_crt_verify_top(mbedtls_x509_crt * child,mbedtls_x509_crt * trust_ca,mbedtls_x509_crl * ca_crl,const mbedtls_x509_crt_profile * profile,int path_cnt,int self_cnt,uint32_t * flags,int (* f_vrfy)(void *,mbedtls_x509_crt *,int,uint32_t *),void * p_vrfy)1894 static int x509_crt_verify_top(
1895 mbedtls_x509_crt *child, mbedtls_x509_crt *trust_ca,
1896 mbedtls_x509_crl *ca_crl,
1897 const mbedtls_x509_crt_profile *profile,
1898 int path_cnt, int self_cnt, uint32_t *flags,
1899 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
1900 void *p_vrfy )
1901 {
1902 int ret;
1903 uint32_t ca_flags = 0;
1904 int check_path_cnt;
1905 unsigned char hash[MBEDTLS_MD_MAX_SIZE];
1906 const mbedtls_md_info_t *md_info;
1907
1908 if( mbedtls_x509_time_is_past( &child->valid_to ) )
1909 *flags |= MBEDTLS_X509_BADCERT_EXPIRED;
1910
1911 if( mbedtls_x509_time_is_future( &child->valid_from ) )
1912 *flags |= MBEDTLS_X509_BADCERT_FUTURE;
1913
1914 if( x509_profile_check_md_alg( profile, child->sig_md ) != 0 )
1915 *flags |= MBEDTLS_X509_BADCERT_BAD_MD;
1916
1917 if( x509_profile_check_pk_alg( profile, child->sig_pk ) != 0 )
1918 *flags |= MBEDTLS_X509_BADCERT_BAD_PK;
1919
1920 /*
1921 * Child is the top of the chain. Check against the trust_ca list.
1922 */
1923 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
1924
1925 md_info = mbedtls_md_info_from_type( child->sig_md );
1926 if( md_info == NULL )
1927 {
1928 /*
1929 * Cannot check 'unknown', no need to try any CA
1930 */
1931 trust_ca = NULL;
1932 }
1933 else
1934 mbedtls_md( md_info, child->tbs.p, child->tbs.len, hash );
1935
1936 for( /* trust_ca */ ; trust_ca != NULL; trust_ca = trust_ca->next )
1937 {
1938 if( x509_crt_check_parent( child, trust_ca, 1, path_cnt == 0 ) != 0 )
1939 continue;
1940
1941 check_path_cnt = path_cnt + 1;
1942
1943 /*
1944 * Reduce check_path_cnt to check against if top of the chain is
1945 * the same as the trusted CA
1946 */
1947 if( child->subject_raw.len == trust_ca->subject_raw.len &&
1948 memcmp( child->subject_raw.p, trust_ca->subject_raw.p,
1949 child->issuer_raw.len ) == 0 )
1950 {
1951 check_path_cnt--;
1952 }
1953
1954 /* Self signed certificates do not count towards the limit */
1955 if( trust_ca->max_pathlen > 0 &&
1956 trust_ca->max_pathlen < check_path_cnt - self_cnt )
1957 {
1958 continue;
1959 }
1960
1961 if( mbedtls_x509_time_is_past( &trust_ca->valid_to ) )
1962 {
1963 continue;
1964 }
1965
1966 if( mbedtls_x509_time_is_future( &trust_ca->valid_from ) )
1967 {
1968 continue;
1969 }
1970
1971 if( mbedtls_pk_verify_ext( child->sig_pk, child->sig_opts, &trust_ca->pk,
1972 child->sig_md, hash, mbedtls_md_get_size( md_info ),
1973 child->sig.p, child->sig.len ) != 0 )
1974 {
1975 continue;
1976 }
1977
1978 /*
1979 * Top of chain is signed by a trusted CA
1980 */
1981 *flags &= ~MBEDTLS_X509_BADCERT_NOT_TRUSTED;
1982
1983 if( x509_profile_check_key( profile, child->sig_pk, &trust_ca->pk ) != 0 )
1984 *flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
1985
1986 break;
1987 }
1988
1989 /*
1990 * If top of chain is not the same as the trusted CA send a verify request
1991 * to the callback for any issues with validity and CRL presence for the
1992 * trusted CA certificate.
1993 */
1994 if( trust_ca != NULL &&
1995 ( child->subject_raw.len != trust_ca->subject_raw.len ||
1996 memcmp( child->subject_raw.p, trust_ca->subject_raw.p,
1997 child->issuer_raw.len ) != 0 ) )
1998 {
1999 #if defined(MBEDTLS_X509_CRL_PARSE_C)
2000 /* Check trusted CA's CRL for the chain's top crt */
2001 *flags |= x509_crt_verifycrl( child, trust_ca, ca_crl, profile );
2002 #else
2003 ((void) ca_crl);
2004 #endif
2005
2006 if( NULL != f_vrfy )
2007 {
2008 if( ( ret = f_vrfy( p_vrfy, trust_ca, path_cnt + 1,
2009 &ca_flags ) ) != 0 )
2010 {
2011 return( ret );
2012 }
2013 }
2014 }
2015
2016 /* Call callback on top cert */
2017 if( NULL != f_vrfy )
2018 {
2019 if( ( ret = f_vrfy( p_vrfy, child, path_cnt, flags ) ) != 0 )
2020 return( ret );
2021 }
2022
2023 *flags |= ca_flags;
2024
2025 return( 0 );
2026 }
2027
x509_crt_verify_child(mbedtls_x509_crt * child,mbedtls_x509_crt * parent,mbedtls_x509_crt * trust_ca,mbedtls_x509_crl * ca_crl,const mbedtls_x509_crt_profile * profile,int path_cnt,int self_cnt,uint32_t * flags,int (* f_vrfy)(void *,mbedtls_x509_crt *,int,uint32_t *),void * p_vrfy)2028 static int x509_crt_verify_child(
2029 mbedtls_x509_crt *child, mbedtls_x509_crt *parent,
2030 mbedtls_x509_crt *trust_ca, mbedtls_x509_crl *ca_crl,
2031 const mbedtls_x509_crt_profile *profile,
2032 int path_cnt, int self_cnt, uint32_t *flags,
2033 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2034 void *p_vrfy )
2035 {
2036 int ret;
2037 uint32_t parent_flags = 0;
2038 unsigned char hash[MBEDTLS_MD_MAX_SIZE];
2039 mbedtls_x509_crt *grandparent;
2040 const mbedtls_md_info_t *md_info;
2041
2042 /* Counting intermediate self signed certificates */
2043 if( ( path_cnt != 0 ) && x509_name_cmp( &child->issuer, &child->subject ) == 0 )
2044 self_cnt++;
2045
2046 /* path_cnt is 0 for the first intermediate CA */
2047 if( 1 + path_cnt > MBEDTLS_X509_MAX_INTERMEDIATE_CA )
2048 {
2049 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
2050 return( MBEDTLS_ERR_X509_CERT_VERIFY_FAILED );
2051 }
2052
2053 if( mbedtls_x509_time_is_past( &child->valid_to ) )
2054 *flags |= MBEDTLS_X509_BADCERT_EXPIRED;
2055
2056 if( mbedtls_x509_time_is_future( &child->valid_from ) )
2057 *flags |= MBEDTLS_X509_BADCERT_FUTURE;
2058
2059 if( x509_profile_check_md_alg( profile, child->sig_md ) != 0 )
2060 *flags |= MBEDTLS_X509_BADCERT_BAD_MD;
2061
2062 if( x509_profile_check_pk_alg( profile, child->sig_pk ) != 0 )
2063 *flags |= MBEDTLS_X509_BADCERT_BAD_PK;
2064
2065 md_info = mbedtls_md_info_from_type( child->sig_md );
2066 if( md_info == NULL )
2067 {
2068 /*
2069 * Cannot check 'unknown' hash
2070 */
2071 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
2072 }
2073 else
2074 {
2075 mbedtls_md( md_info, child->tbs.p, child->tbs.len, hash );
2076
2077 if( x509_profile_check_key( profile, child->sig_pk, &parent->pk ) != 0 )
2078 *flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
2079
2080 if( mbedtls_pk_verify_ext( child->sig_pk, child->sig_opts, &parent->pk,
2081 child->sig_md, hash, mbedtls_md_get_size( md_info ),
2082 child->sig.p, child->sig.len ) != 0 )
2083 {
2084 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
2085 }
2086 }
2087
2088 #if defined(MBEDTLS_X509_CRL_PARSE_C)
2089 /* Check trusted CA's CRL for the given crt */
2090 *flags |= x509_crt_verifycrl(child, parent, ca_crl, profile );
2091 #endif
2092
2093 /* Look for a grandparent in trusted CAs */
2094 for( grandparent = trust_ca;
2095 grandparent != NULL;
2096 grandparent = grandparent->next )
2097 {
2098 if( x509_crt_check_parent( parent, grandparent,
2099 0, path_cnt == 0 ) == 0 )
2100 break;
2101 }
2102
2103 if( grandparent != NULL )
2104 {
2105 ret = x509_crt_verify_top( parent, grandparent, ca_crl, profile,
2106 path_cnt + 1, self_cnt, &parent_flags, f_vrfy, p_vrfy );
2107 if( ret != 0 )
2108 return( ret );
2109 }
2110 else
2111 {
2112 /* Look for a grandparent upwards the chain */
2113 for( grandparent = parent->next;
2114 grandparent != NULL;
2115 grandparent = grandparent->next )
2116 {
2117 /* +2 because the current step is not yet accounted for
2118 * and because max_pathlen is one higher than it should be.
2119 * Also self signed certificates do not count to the limit. */
2120 if( grandparent->max_pathlen > 0 &&
2121 grandparent->max_pathlen < 2 + path_cnt - self_cnt )
2122 {
2123 continue;
2124 }
2125
2126 if( x509_crt_check_parent( parent, grandparent,
2127 0, path_cnt == 0 ) == 0 )
2128 break;
2129 }
2130
2131 /* Is our parent part of the chain or at the top? */
2132 if( grandparent != NULL )
2133 {
2134 ret = x509_crt_verify_child( parent, grandparent, trust_ca, ca_crl,
2135 profile, path_cnt + 1, self_cnt, &parent_flags,
2136 f_vrfy, p_vrfy );
2137 if( ret != 0 )
2138 return( ret );
2139 }
2140 else
2141 {
2142 ret = x509_crt_verify_top( parent, trust_ca, ca_crl, profile,
2143 path_cnt + 1, self_cnt, &parent_flags,
2144 f_vrfy, p_vrfy );
2145 if( ret != 0 )
2146 return( ret );
2147 }
2148 }
2149
2150 /* child is verified to be a child of the parent, call verify callback */
2151 if( NULL != f_vrfy )
2152 if( ( ret = f_vrfy( p_vrfy, child, path_cnt, flags ) ) != 0 )
2153 return( ret );
2154
2155 *flags |= parent_flags;
2156
2157 return( 0 );
2158 }
2159
2160 /*
2161 * Verify the certificate validity
2162 */
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)2163 int mbedtls_x509_crt_verify( mbedtls_x509_crt *crt,
2164 mbedtls_x509_crt *trust_ca,
2165 mbedtls_x509_crl *ca_crl,
2166 const char *cn, uint32_t *flags,
2167 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2168 void *p_vrfy )
2169 {
2170 return( mbedtls_x509_crt_verify_with_profile( crt, trust_ca, ca_crl,
2171 &mbedtls_x509_crt_profile_default, cn, flags, f_vrfy, p_vrfy ) );
2172 }
2173
2174
2175 /*
2176 * Verify the certificate validity, with profile
2177 */
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)2178 int mbedtls_x509_crt_verify_with_profile( mbedtls_x509_crt *crt,
2179 mbedtls_x509_crt *trust_ca,
2180 mbedtls_x509_crl *ca_crl,
2181 const mbedtls_x509_crt_profile *profile,
2182 const char *cn, uint32_t *flags,
2183 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
2184 void *p_vrfy )
2185 {
2186 size_t cn_len;
2187 int ret;
2188 int pathlen = 0, selfsigned = 0;
2189 mbedtls_x509_crt *parent;
2190 mbedtls_x509_name *name;
2191 mbedtls_x509_sequence *cur = NULL;
2192 mbedtls_pk_type_t pk_type;
2193
2194 if( profile == NULL )
2195 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
2196
2197 *flags = 0;
2198
2199 if( cn != NULL )
2200 {
2201 name = &crt->subject;
2202 cn_len = strlen( cn );
2203
2204 if( crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME )
2205 {
2206 cur = &crt->subject_alt_names;
2207
2208 while( cur != NULL )
2209 {
2210 if( cur->buf.len == cn_len &&
2211 x509_memcasecmp( cn, cur->buf.p, cn_len ) == 0 )
2212 break;
2213
2214 if( cur->buf.len > 2 &&
2215 memcmp( cur->buf.p, "*.", 2 ) == 0 &&
2216 x509_check_wildcard( cn, &cur->buf ) == 0 )
2217 {
2218 break;
2219 }
2220
2221 cur = cur->next;
2222 }
2223
2224 if( cur == NULL )
2225 *flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH;
2226 }
2227 else
2228 {
2229 while( name != NULL )
2230 {
2231 if( MBEDTLS_OID_CMP( MBEDTLS_OID_AT_CN, &name->oid ) == 0 )
2232 {
2233 if( name->val.len == cn_len &&
2234 x509_memcasecmp( name->val.p, cn, cn_len ) == 0 )
2235 break;
2236
2237 if( name->val.len > 2 &&
2238 memcmp( name->val.p, "*.", 2 ) == 0 &&
2239 x509_check_wildcard( cn, &name->val ) == 0 )
2240 break;
2241 }
2242
2243 name = name->next;
2244 }
2245
2246 if( name == NULL )
2247 *flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH;
2248 }
2249 }
2250
2251 /* Check the type and size of the key */
2252 pk_type = mbedtls_pk_get_type( &crt->pk );
2253
2254 if( x509_profile_check_pk_alg( profile, pk_type ) != 0 )
2255 *flags |= MBEDTLS_X509_BADCERT_BAD_PK;
2256
2257 if( x509_profile_check_key( profile, pk_type, &crt->pk ) != 0 )
2258 *flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
2259
2260 /* Look for a parent in trusted CAs */
2261 for( parent = trust_ca; parent != NULL; parent = parent->next )
2262 {
2263 if( x509_crt_check_parent( crt, parent, 0, pathlen == 0 ) == 0 )
2264 break;
2265 }
2266
2267 if( parent != NULL )
2268 {
2269 ret = x509_crt_verify_top( crt, parent, ca_crl, profile,
2270 pathlen, selfsigned, flags, f_vrfy, p_vrfy );
2271 if( ret != 0 )
2272 return( ret );
2273 }
2274 else
2275 {
2276 /* Look for a parent upwards the chain */
2277 for( parent = crt->next; parent != NULL; parent = parent->next )
2278 if( x509_crt_check_parent( crt, parent, 0, pathlen == 0 ) == 0 )
2279 break;
2280
2281 /* Are we part of the chain or at the top? */
2282 if( parent != NULL )
2283 {
2284 ret = x509_crt_verify_child( crt, parent, trust_ca, ca_crl, profile,
2285 pathlen, selfsigned, flags, f_vrfy, p_vrfy );
2286 if( ret != 0 )
2287 return( ret );
2288 }
2289 else
2290 {
2291 ret = x509_crt_verify_top( crt, trust_ca, ca_crl, profile,
2292 pathlen, selfsigned, flags, f_vrfy, p_vrfy );
2293 if( ret != 0 )
2294 return( ret );
2295 }
2296 }
2297
2298 if( *flags != 0 )
2299 return( MBEDTLS_ERR_X509_CERT_VERIFY_FAILED );
2300
2301 return( 0 );
2302 }
2303
2304 /*
2305 * Initialize a certificate chain
2306 */
mbedtls_x509_crt_init(mbedtls_x509_crt * crt)2307 void mbedtls_x509_crt_init( mbedtls_x509_crt *crt )
2308 {
2309 memset( crt, 0, sizeof(mbedtls_x509_crt) );
2310 }
2311
2312 /*
2313 * Unallocate all certificate data
2314 */
mbedtls_x509_crt_free(mbedtls_x509_crt * crt)2315 void mbedtls_x509_crt_free( mbedtls_x509_crt *crt )
2316 {
2317 mbedtls_x509_crt *cert_cur = crt;
2318 mbedtls_x509_crt *cert_prv;
2319 mbedtls_x509_name *name_cur;
2320 mbedtls_x509_name *name_prv;
2321 mbedtls_x509_sequence *seq_cur;
2322 mbedtls_x509_sequence *seq_prv;
2323
2324 if( crt == NULL )
2325 return;
2326
2327 do
2328 {
2329 mbedtls_pk_free( &cert_cur->pk );
2330
2331 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
2332 mbedtls_free( cert_cur->sig_opts );
2333 #endif
2334
2335 name_cur = cert_cur->issuer.next;
2336 while( name_cur != NULL )
2337 {
2338 name_prv = name_cur;
2339 name_cur = name_cur->next;
2340 mbedtls_zeroize( name_prv, sizeof( mbedtls_x509_name ) );
2341 mbedtls_free( name_prv );
2342 }
2343
2344 name_cur = cert_cur->subject.next;
2345 while( name_cur != NULL )
2346 {
2347 name_prv = name_cur;
2348 name_cur = name_cur->next;
2349 mbedtls_zeroize( name_prv, sizeof( mbedtls_x509_name ) );
2350 mbedtls_free( name_prv );
2351 }
2352
2353 seq_cur = cert_cur->ext_key_usage.next;
2354 while( seq_cur != NULL )
2355 {
2356 seq_prv = seq_cur;
2357 seq_cur = seq_cur->next;
2358 mbedtls_zeroize( seq_prv, sizeof( mbedtls_x509_sequence ) );
2359 mbedtls_free( seq_prv );
2360 }
2361
2362 seq_cur = cert_cur->subject_alt_names.next;
2363 while( seq_cur != NULL )
2364 {
2365 seq_prv = seq_cur;
2366 seq_cur = seq_cur->next;
2367 mbedtls_zeroize( seq_prv, sizeof( mbedtls_x509_sequence ) );
2368 mbedtls_free( seq_prv );
2369 }
2370
2371 if( cert_cur->raw.p != NULL )
2372 {
2373 mbedtls_zeroize( cert_cur->raw.p, cert_cur->raw.len );
2374 mbedtls_free( cert_cur->raw.p );
2375 }
2376
2377 cert_cur = cert_cur->next;
2378 }
2379 while( cert_cur != NULL );
2380
2381 cert_cur = crt;
2382 do
2383 {
2384 cert_prv = cert_cur;
2385 cert_cur = cert_cur->next;
2386
2387 mbedtls_zeroize( cert_prv, sizeof( mbedtls_x509_crt ) );
2388 if( cert_prv != crt )
2389 mbedtls_free( cert_prv );
2390 }
2391 while( cert_cur != NULL );
2392 }
2393
2394 #endif /* MBEDTLS_X509_CRT_PARSE_C */
2395
