1 /*
2 * X.509 certificate parsing and verification
3 *
4 * Copyright The Mbed TLS Contributors
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 /*
20 * The ITU-T X.509 standard defines a certificate format for PKI.
21 *
22 * http://www.ietf.org/rfc/rfc5280.txt (Certificates and CRLs)
23 * http://www.ietf.org/rfc/rfc3279.txt (Alg IDs for CRLs)
24 * http://www.ietf.org/rfc/rfc2986.txt (CSRs, aka PKCS#10)
25 *
26 * http://www.itu.int/ITU-T/studygroups/com17/languages/X.680-0207.pdf
27 * http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf
28 *
29 * [SIRO] https://cabforum.org/wp-content/uploads/Chunghwatelecom201503cabforumV4.pdf
30 */
31
32 #include "common.h"
33
34 #if defined(MBEDTLS_X509_CRT_PARSE_C)
35
36 #include "mbedtls/x509_crt.h"
37 #include "mbedtls/error.h"
38 #include "mbedtls/oid.h"
39 #include "mbedtls/platform_util.h"
40
41 #include <string.h>
42
43 #if defined(MBEDTLS_PEM_PARSE_C)
44 #include "mbedtls/pem.h"
45 #endif
46
47 #if defined(MBEDTLS_USE_PSA_CRYPTO)
48 #include "psa/crypto.h"
49 #include "mbedtls/psa_util.h"
50 #endif
51
52 #if defined(MBEDTLS_PLATFORM_C)
53 #include "mbedtls/platform.h"
54 #else
55 #include <stdio.h>
56 #include <stdlib.h>
57 #define mbedtls_free free
58 #define mbedtls_calloc calloc
59 #define mbedtls_snprintf snprintf
60 #endif
61
62 #if defined(MBEDTLS_THREADING_C)
63 #include "mbedtls/threading.h"
64 #endif
65
66 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
67 #include <windows.h>
68 #else
69 #include <time.h>
70 #endif
71
72 #if defined(MBEDTLS_FS_IO)
73 #include <stdio.h>
74 #if !defined(_WIN32) || defined(EFIX64) || defined(EFI32)
75 #include <sys/types.h>
76 #include <sys/stat.h>
77 #if defined(__MBED__)
78 #include <platform/mbed_retarget.h>
79 #else
80 #include <dirent.h>
81 #endif /* __MBED__ */
82 #endif /* !_WIN32 || EFIX64 || EFI32 */
83 #endif
84
85 /*
86 * Item in a verification chain: cert and flags for it
87 */
88 typedef struct {
89 mbedtls_x509_crt *crt;
90 uint32_t flags;
91 } x509_crt_verify_chain_item;
92
93 /*
94 * Max size of verification chain: end-entity + intermediates + trusted root
95 */
96 #define X509_MAX_VERIFY_CHAIN_SIZE ( MBEDTLS_X509_MAX_INTERMEDIATE_CA + 2 )
97
98 /* Default profile. Do not remove items unless there are serious security
99 * concerns. */
100 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_default =
101 {
102 /* Hashes from SHA-256 and above. Note that this selection
103 * should be aligned with ssl_preset_default_hashes in ssl_tls.c. */
104 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
105 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ) |
106 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA512 ),
107 0xFFFFFFF, /* Any PK alg */
108 #if defined(MBEDTLS_ECP_C)
109 /* Curves at or above 128-bit security level. Note that this selection
110 * should be aligned with ssl_preset_default_curves in ssl_tls.c. */
111 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256R1 ) |
112 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP384R1 ) |
113 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP521R1 ) |
114 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP256R1 ) |
115 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP384R1 ) |
116 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP512R1 ) |
117 0,
118 #else
119 0,
120 #endif
121 2048,
122 };
123
124 /* Next-generation profile. Currently identical to the default, but may
125 * be tightened at any time. */
126 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_next =
127 {
128 /* Hashes from SHA-256 and above. */
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 #if defined(MBEDTLS_ECP_C)
134 /* Curves at or above 128-bit security level. */
135 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256R1 ) |
136 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP384R1 ) |
137 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP521R1 ) |
138 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP256R1 ) |
139 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP384R1 ) |
140 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_BP512R1 ) |
141 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256K1 ),
142 #else
143 0,
144 #endif
145 2048,
146 };
147
148 /*
149 * NSA Suite B Profile
150 */
151 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_suiteb =
152 {
153 /* Only SHA-256 and 384 */
154 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA256 ) |
155 MBEDTLS_X509_ID_FLAG( MBEDTLS_MD_SHA384 ),
156 /* Only ECDSA */
157 MBEDTLS_X509_ID_FLAG( MBEDTLS_PK_ECDSA ) |
158 MBEDTLS_X509_ID_FLAG( MBEDTLS_PK_ECKEY ),
159 #if defined(MBEDTLS_ECP_C)
160 /* Only NIST P-256 and P-384 */
161 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP256R1 ) |
162 MBEDTLS_X509_ID_FLAG( MBEDTLS_ECP_DP_SECP384R1 ),
163 #else
164 0,
165 #endif
166 0,
167 };
168
169 /*
170 * Empty / all-forbidden profile
171 */
172 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_none =
173 {
174 0,
175 0,
176 0,
177 (uint32_t) -1,
178 };
179
180 /*
181 * Check md_alg against profile
182 * Return 0 if md_alg is acceptable for this profile, -1 otherwise
183 */
x509_profile_check_md_alg(const mbedtls_x509_crt_profile * profile,mbedtls_md_type_t md_alg)184 static int x509_profile_check_md_alg( const mbedtls_x509_crt_profile *profile,
185 mbedtls_md_type_t md_alg )
186 {
187 if( md_alg == MBEDTLS_MD_NONE )
188 return( -1 );
189
190 if( ( profile->allowed_mds & MBEDTLS_X509_ID_FLAG( md_alg ) ) != 0 )
191 return( 0 );
192
193 return( -1 );
194 }
195
196 /*
197 * Check pk_alg against profile
198 * Return 0 if pk_alg is acceptable for this profile, -1 otherwise
199 */
x509_profile_check_pk_alg(const mbedtls_x509_crt_profile * profile,mbedtls_pk_type_t pk_alg)200 static int x509_profile_check_pk_alg( const mbedtls_x509_crt_profile *profile,
201 mbedtls_pk_type_t pk_alg )
202 {
203 if( pk_alg == MBEDTLS_PK_NONE )
204 return( -1 );
205
206 if( ( profile->allowed_pks & MBEDTLS_X509_ID_FLAG( pk_alg ) ) != 0 )
207 return( 0 );
208
209 return( -1 );
210 }
211
212 /*
213 * Check key against profile
214 * Return 0 if pk is acceptable for this profile, -1 otherwise
215 */
x509_profile_check_key(const mbedtls_x509_crt_profile * profile,const mbedtls_pk_context * pk)216 static int x509_profile_check_key( const mbedtls_x509_crt_profile *profile,
217 const mbedtls_pk_context *pk )
218 {
219 const mbedtls_pk_type_t pk_alg = mbedtls_pk_get_type( pk );
220
221 #if defined(MBEDTLS_RSA_C)
222 if( pk_alg == MBEDTLS_PK_RSA || pk_alg == MBEDTLS_PK_RSASSA_PSS )
223 {
224 if( mbedtls_pk_get_bitlen( pk ) >= profile->rsa_min_bitlen )
225 return( 0 );
226
227 return( -1 );
228 }
229 #endif
230
231 #if defined(MBEDTLS_ECP_C)
232 if( pk_alg == MBEDTLS_PK_ECDSA ||
233 pk_alg == MBEDTLS_PK_ECKEY ||
234 pk_alg == MBEDTLS_PK_ECKEY_DH )
235 {
236 const mbedtls_ecp_group_id gid = mbedtls_pk_ec( *pk )->grp.id;
237
238 if( gid == MBEDTLS_ECP_DP_NONE )
239 return( -1 );
240
241 if( ( profile->allowed_curves & MBEDTLS_X509_ID_FLAG( gid ) ) != 0 )
242 return( 0 );
243
244 return( -1 );
245 }
246 #endif
247
248 return( -1 );
249 }
250
251 /*
252 * Like memcmp, but case-insensitive and always returns -1 if different
253 */
x509_memcasecmp(const void * s1,const void * s2,size_t len)254 static int x509_memcasecmp( const void *s1, const void *s2, size_t len )
255 {
256 size_t i;
257 unsigned char diff;
258 const unsigned char *n1 = s1, *n2 = s2;
259
260 for( i = 0; i < len; i++ )
261 {
262 diff = n1[i] ^ n2[i];
263
264 if( diff == 0 )
265 continue;
266
267 if( diff == 32 &&
268 ( ( n1[i] >= 'a' && n1[i] <= 'z' ) ||
269 ( n1[i] >= 'A' && n1[i] <= 'Z' ) ) )
270 {
271 continue;
272 }
273
274 return( -1 );
275 }
276
277 return( 0 );
278 }
279
280 /*
281 * Return 0 if name matches wildcard, -1 otherwise
282 */
x509_check_wildcard(const char * cn,const mbedtls_x509_buf * name)283 static int x509_check_wildcard( const char *cn, const mbedtls_x509_buf *name )
284 {
285 size_t i;
286 size_t cn_idx = 0, cn_len = strlen( cn );
287
288 /* We can't have a match if there is no wildcard to match */
289 if( name->len < 3 || name->p[0] != '*' || name->p[1] != '.' )
290 return( -1 );
291
292 for( i = 0; i < cn_len; ++i )
293 {
294 if( cn[i] == '.' )
295 {
296 cn_idx = i;
297 break;
298 }
299 }
300
301 if( cn_idx == 0 )
302 return( -1 );
303
304 if( cn_len - cn_idx == name->len - 1 &&
305 x509_memcasecmp( name->p + 1, cn + cn_idx, name->len - 1 ) == 0 )
306 {
307 return( 0 );
308 }
309
310 return( -1 );
311 }
312
313 /*
314 * Compare two X.509 strings, case-insensitive, and allowing for some encoding
315 * variations (but not all).
316 *
317 * Return 0 if equal, -1 otherwise.
318 */
x509_string_cmp(const mbedtls_x509_buf * a,const mbedtls_x509_buf * b)319 static int x509_string_cmp( const mbedtls_x509_buf *a, const mbedtls_x509_buf *b )
320 {
321 if( a->tag == b->tag &&
322 a->len == b->len &&
323 memcmp( a->p, b->p, b->len ) == 0 )
324 {
325 return( 0 );
326 }
327
328 if( ( a->tag == MBEDTLS_ASN1_UTF8_STRING || a->tag == MBEDTLS_ASN1_PRINTABLE_STRING ) &&
329 ( b->tag == MBEDTLS_ASN1_UTF8_STRING || b->tag == MBEDTLS_ASN1_PRINTABLE_STRING ) &&
330 a->len == b->len &&
331 x509_memcasecmp( a->p, b->p, b->len ) == 0 )
332 {
333 return( 0 );
334 }
335
336 return( -1 );
337 }
338
339 /*
340 * Compare two X.509 Names (aka rdnSequence).
341 *
342 * See RFC 5280 section 7.1, though we don't implement the whole algorithm:
343 * we sometimes return unequal when the full algorithm would return equal,
344 * but never the other way. (In particular, we don't do Unicode normalisation
345 * or space folding.)
346 *
347 * Return 0 if equal, -1 otherwise.
348 */
x509_name_cmp(const mbedtls_x509_name * a,const mbedtls_x509_name * b)349 static int x509_name_cmp( const mbedtls_x509_name *a, const mbedtls_x509_name *b )
350 {
351 /* Avoid recursion, it might not be optimised by the compiler */
352 while( a != NULL || b != NULL )
353 {
354 if( a == NULL || b == NULL )
355 return( -1 );
356
357 /* type */
358 if( a->oid.tag != b->oid.tag ||
359 a->oid.len != b->oid.len ||
360 memcmp( a->oid.p, b->oid.p, b->oid.len ) != 0 )
361 {
362 return( -1 );
363 }
364
365 /* value */
366 if( x509_string_cmp( &a->val, &b->val ) != 0 )
367 return( -1 );
368
369 /* structure of the list of sets */
370 if( a->next_merged != b->next_merged )
371 return( -1 );
372
373 a = a->next;
374 b = b->next;
375 }
376
377 /* a == NULL == b */
378 return( 0 );
379 }
380
381 /*
382 * Reset (init or clear) a verify_chain
383 */
x509_crt_verify_chain_reset(mbedtls_x509_crt_verify_chain * ver_chain)384 static void x509_crt_verify_chain_reset(
385 mbedtls_x509_crt_verify_chain *ver_chain )
386 {
387 size_t i;
388
389 for( i = 0; i < MBEDTLS_X509_MAX_VERIFY_CHAIN_SIZE; i++ )
390 {
391 ver_chain->items[i].crt = NULL;
392 ver_chain->items[i].flags = (uint32_t) -1;
393 }
394
395 ver_chain->len = 0;
396
397 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
398 ver_chain->trust_ca_cb_result = NULL;
399 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
400 }
401
402 /*
403 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
404 */
x509_get_version(unsigned char ** p,const unsigned char * end,int * ver)405 static int x509_get_version( unsigned char **p,
406 const unsigned char *end,
407 int *ver )
408 {
409 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
410 size_t len;
411
412 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
413 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 0 ) ) != 0 )
414 {
415 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
416 {
417 *ver = 0;
418 return( 0 );
419 }
420
421 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_FORMAT, ret ) );
422 }
423
424 end = *p + len;
425
426 if( ( ret = mbedtls_asn1_get_int( p, end, ver ) ) != 0 )
427 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_VERSION, ret ) );
428
429 if( *p != end )
430 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_VERSION,
431 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
432
433 return( 0 );
434 }
435
436 /*
437 * Validity ::= SEQUENCE {
438 * notBefore Time,
439 * notAfter Time }
440 */
x509_get_dates(unsigned char ** p,const unsigned char * end,mbedtls_x509_time * from,mbedtls_x509_time * to)441 static int x509_get_dates( unsigned char **p,
442 const unsigned char *end,
443 mbedtls_x509_time *from,
444 mbedtls_x509_time *to )
445 {
446 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
447 size_t len;
448
449 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
450 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
451 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_DATE, ret ) );
452
453 end = *p + len;
454
455 if( ( ret = mbedtls_x509_get_time( p, end, from ) ) != 0 )
456 return( ret );
457
458 if( ( ret = mbedtls_x509_get_time( p, end, to ) ) != 0 )
459 return( ret );
460
461 if( *p != end )
462 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_DATE,
463 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
464
465 return( 0 );
466 }
467
468 /*
469 * X.509 v2/v3 unique identifier (not parsed)
470 */
x509_get_uid(unsigned char ** p,const unsigned char * end,mbedtls_x509_buf * uid,int n)471 static int x509_get_uid( unsigned char **p,
472 const unsigned char *end,
473 mbedtls_x509_buf *uid, int n )
474 {
475 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
476
477 if( *p == end )
478 return( 0 );
479
480 uid->tag = **p;
481
482 if( ( ret = mbedtls_asn1_get_tag( p, end, &uid->len,
483 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | n ) ) != 0 )
484 {
485 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
486 return( 0 );
487
488 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_FORMAT, ret ) );
489 }
490
491 uid->p = *p;
492 *p += uid->len;
493
494 return( 0 );
495 }
496
x509_get_basic_constraints(unsigned char ** p,const unsigned char * end,int * ca_istrue,int * max_pathlen)497 static int x509_get_basic_constraints( unsigned char **p,
498 const unsigned char *end,
499 int *ca_istrue,
500 int *max_pathlen )
501 {
502 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
503 size_t len;
504
505 /*
506 * BasicConstraints ::= SEQUENCE {
507 * cA BOOLEAN DEFAULT FALSE,
508 * pathLenConstraint INTEGER (0..MAX) OPTIONAL }
509 */
510 *ca_istrue = 0; /* DEFAULT FALSE */
511 *max_pathlen = 0; /* endless */
512
513 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
514 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
515 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
516
517 if( *p == end )
518 return( 0 );
519
520 if( ( ret = mbedtls_asn1_get_bool( p, end, ca_istrue ) ) != 0 )
521 {
522 if( ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
523 ret = mbedtls_asn1_get_int( p, end, ca_istrue );
524
525 if( ret != 0 )
526 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
527
528 if( *ca_istrue != 0 )
529 *ca_istrue = 1;
530 }
531
532 if( *p == end )
533 return( 0 );
534
535 if( ( ret = mbedtls_asn1_get_int( p, end, max_pathlen ) ) != 0 )
536 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
537
538 if( *p != end )
539 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
540 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
541
542 /* Do not accept max_pathlen equal to INT_MAX to avoid a signed integer
543 * overflow, which is an undefined behavior. */
544 if( *max_pathlen == INT_MAX )
545 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
546 MBEDTLS_ERR_ASN1_INVALID_LENGTH ) );
547
548 (*max_pathlen)++;
549
550 return( 0 );
551 }
552
x509_get_ns_cert_type(unsigned char ** p,const unsigned char * end,unsigned char * ns_cert_type)553 static int x509_get_ns_cert_type( unsigned char **p,
554 const unsigned char *end,
555 unsigned char *ns_cert_type)
556 {
557 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
558 mbedtls_x509_bitstring bs = { 0, 0, NULL };
559
560 if( ( ret = mbedtls_asn1_get_bitstring( p, end, &bs ) ) != 0 )
561 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
562
563 if( bs.len != 1 )
564 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
565 MBEDTLS_ERR_ASN1_INVALID_LENGTH ) );
566
567 /* Get actual bitstring */
568 *ns_cert_type = *bs.p;
569 return( 0 );
570 }
571
x509_get_key_usage(unsigned char ** p,const unsigned char * end,unsigned int * key_usage)572 static int x509_get_key_usage( unsigned char **p,
573 const unsigned char *end,
574 unsigned int *key_usage)
575 {
576 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
577 size_t i;
578 mbedtls_x509_bitstring bs = { 0, 0, NULL };
579
580 if( ( ret = mbedtls_asn1_get_bitstring( p, end, &bs ) ) != 0 )
581 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
582
583 if( bs.len < 1 )
584 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
585 MBEDTLS_ERR_ASN1_INVALID_LENGTH ) );
586
587 /* Get actual bitstring */
588 *key_usage = 0;
589 for( i = 0; i < bs.len && i < sizeof( unsigned int ); i++ )
590 {
591 *key_usage |= (unsigned int) bs.p[i] << (8*i);
592 }
593
594 return( 0 );
595 }
596
597 /*
598 * ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId
599 *
600 * KeyPurposeId ::= OBJECT IDENTIFIER
601 */
x509_get_ext_key_usage(unsigned char ** p,const unsigned char * end,mbedtls_x509_sequence * ext_key_usage)602 static int x509_get_ext_key_usage( unsigned char **p,
603 const unsigned char *end,
604 mbedtls_x509_sequence *ext_key_usage)
605 {
606 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
607
608 if( ( ret = mbedtls_asn1_get_sequence_of( p, end, ext_key_usage, MBEDTLS_ASN1_OID ) ) != 0 )
609 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
610
611 /* Sequence length must be >= 1 */
612 if( ext_key_usage->buf.p == NULL )
613 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
614 MBEDTLS_ERR_ASN1_INVALID_LENGTH ) );
615
616 return( 0 );
617 }
618
619 /*
620 * SubjectAltName ::= GeneralNames
621 *
622 * GeneralNames ::= SEQUENCE SIZE (1..MAX) OF GeneralName
623 *
624 * GeneralName ::= CHOICE {
625 * otherName [0] OtherName,
626 * rfc822Name [1] IA5String,
627 * dNSName [2] IA5String,
628 * x400Address [3] ORAddress,
629 * directoryName [4] Name,
630 * ediPartyName [5] EDIPartyName,
631 * uniformResourceIdentifier [6] IA5String,
632 * iPAddress [7] OCTET STRING,
633 * registeredID [8] OBJECT IDENTIFIER }
634 *
635 * OtherName ::= SEQUENCE {
636 * type-id OBJECT IDENTIFIER,
637 * value [0] EXPLICIT ANY DEFINED BY type-id }
638 *
639 * EDIPartyName ::= SEQUENCE {
640 * nameAssigner [0] DirectoryString OPTIONAL,
641 * partyName [1] DirectoryString }
642 *
643 * NOTE: we list all types, but only use dNSName and otherName
644 * of type HwModuleName, as defined in RFC 4108, at this point.
645 */
x509_get_subject_alt_name(unsigned char ** p,const unsigned char * end,mbedtls_x509_sequence * subject_alt_name)646 static int x509_get_subject_alt_name( unsigned char **p,
647 const unsigned char *end,
648 mbedtls_x509_sequence *subject_alt_name )
649 {
650 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
651 size_t len, tag_len;
652 mbedtls_asn1_buf *buf;
653 unsigned char tag;
654 mbedtls_asn1_sequence *cur = subject_alt_name;
655
656 /* Get main sequence tag */
657 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
658 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
659 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
660
661 if( *p + len != end )
662 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
663 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
664
665 while( *p < end )
666 {
667 mbedtls_x509_subject_alternative_name dummy_san_buf;
668 memset( &dummy_san_buf, 0, sizeof( dummy_san_buf ) );
669
670 tag = **p;
671 (*p)++;
672 if( ( ret = mbedtls_asn1_get_len( p, end, &tag_len ) ) != 0 )
673 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
674
675 if( ( tag & MBEDTLS_ASN1_TAG_CLASS_MASK ) !=
676 MBEDTLS_ASN1_CONTEXT_SPECIFIC )
677 {
678 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
679 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) );
680 }
681
682 /*
683 * Check that the SAN is structured correctly.
684 */
685 ret = mbedtls_x509_parse_subject_alt_name( &(cur->buf), &dummy_san_buf );
686 /*
687 * In case the extension is malformed, return an error,
688 * and clear the allocated sequences.
689 */
690 if( ret != 0 && ret != MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE )
691 {
692 mbedtls_x509_sequence *seq_cur = subject_alt_name->next;
693 mbedtls_x509_sequence *seq_prv;
694 while( seq_cur != NULL )
695 {
696 seq_prv = seq_cur;
697 seq_cur = seq_cur->next;
698 mbedtls_platform_zeroize( seq_prv,
699 sizeof( mbedtls_x509_sequence ) );
700 mbedtls_free( seq_prv );
701 }
702 subject_alt_name->next = NULL;
703 return( ret );
704 }
705
706 /* Allocate and assign next pointer */
707 if( cur->buf.p != NULL )
708 {
709 if( cur->next != NULL )
710 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS );
711
712 cur->next = mbedtls_calloc( 1, sizeof( mbedtls_asn1_sequence ) );
713
714 if( cur->next == NULL )
715 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
716 MBEDTLS_ERR_ASN1_ALLOC_FAILED ) );
717
718 cur = cur->next;
719 }
720
721 buf = &(cur->buf);
722 buf->tag = tag;
723 buf->p = *p;
724 buf->len = tag_len;
725 *p += buf->len;
726 }
727
728 /* Set final sequence entry's next pointer to NULL */
729 cur->next = NULL;
730
731 if( *p != end )
732 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
733 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
734
735 return( 0 );
736 }
737
738 /*
739 * id-ce-certificatePolicies OBJECT IDENTIFIER ::= { id-ce 32 }
740 *
741 * anyPolicy OBJECT IDENTIFIER ::= { id-ce-certificatePolicies 0 }
742 *
743 * certificatePolicies ::= SEQUENCE SIZE (1..MAX) OF PolicyInformation
744 *
745 * PolicyInformation ::= SEQUENCE {
746 * policyIdentifier CertPolicyId,
747 * policyQualifiers SEQUENCE SIZE (1..MAX) OF
748 * PolicyQualifierInfo OPTIONAL }
749 *
750 * CertPolicyId ::= OBJECT IDENTIFIER
751 *
752 * PolicyQualifierInfo ::= SEQUENCE {
753 * policyQualifierId PolicyQualifierId,
754 * qualifier ANY DEFINED BY policyQualifierId }
755 *
756 * -- policyQualifierIds for Internet policy qualifiers
757 *
758 * id-qt OBJECT IDENTIFIER ::= { id-pkix 2 }
759 * id-qt-cps OBJECT IDENTIFIER ::= { id-qt 1 }
760 * id-qt-unotice OBJECT IDENTIFIER ::= { id-qt 2 }
761 *
762 * PolicyQualifierId ::= OBJECT IDENTIFIER ( id-qt-cps | id-qt-unotice )
763 *
764 * Qualifier ::= CHOICE {
765 * cPSuri CPSuri,
766 * userNotice UserNotice }
767 *
768 * CPSuri ::= IA5String
769 *
770 * UserNotice ::= SEQUENCE {
771 * noticeRef NoticeReference OPTIONAL,
772 * explicitText DisplayText OPTIONAL }
773 *
774 * NoticeReference ::= SEQUENCE {
775 * organization DisplayText,
776 * noticeNumbers SEQUENCE OF INTEGER }
777 *
778 * DisplayText ::= CHOICE {
779 * ia5String IA5String (SIZE (1..200)),
780 * visibleString VisibleString (SIZE (1..200)),
781 * bmpString BMPString (SIZE (1..200)),
782 * utf8String UTF8String (SIZE (1..200)) }
783 *
784 * NOTE: we only parse and use anyPolicy without qualifiers at this point
785 * as defined in RFC 5280.
786 */
x509_get_certificate_policies(unsigned char ** p,const unsigned char * end,mbedtls_x509_sequence * certificate_policies)787 static int x509_get_certificate_policies( unsigned char **p,
788 const unsigned char *end,
789 mbedtls_x509_sequence *certificate_policies )
790 {
791 int ret, parse_ret = 0;
792 size_t len;
793 mbedtls_asn1_buf *buf;
794 mbedtls_asn1_sequence *cur = certificate_policies;
795
796 /* Get main sequence tag */
797 ret = mbedtls_asn1_get_tag( p, end, &len,
798 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE );
799 if( ret != 0 )
800 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
801
802 if( *p + len != end )
803 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
804 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
805
806 /*
807 * Cannot be an empty sequence.
808 */
809 if( len == 0 )
810 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
811 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
812
813 while( *p < end )
814 {
815 mbedtls_x509_buf policy_oid;
816 const unsigned char *policy_end;
817
818 /*
819 * Get the policy sequence
820 */
821 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
822 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
823 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
824
825 policy_end = *p + len;
826
827 if( ( ret = mbedtls_asn1_get_tag( p, policy_end, &len,
828 MBEDTLS_ASN1_OID ) ) != 0 )
829 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
830
831 policy_oid.tag = MBEDTLS_ASN1_OID;
832 policy_oid.len = len;
833 policy_oid.p = *p;
834
835 /*
836 * Only AnyPolicy is currently supported when enforcing policy.
837 */
838 if( MBEDTLS_OID_CMP( MBEDTLS_OID_ANY_POLICY, &policy_oid ) != 0 )
839 {
840 /*
841 * Set the parsing return code but continue parsing, in case this
842 * extension is critical.
843 */
844 parse_ret = MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
845 }
846
847 /* Allocate and assign next pointer */
848 if( cur->buf.p != NULL )
849 {
850 if( cur->next != NULL )
851 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS );
852
853 cur->next = mbedtls_calloc( 1, sizeof( mbedtls_asn1_sequence ) );
854
855 if( cur->next == NULL )
856 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
857 MBEDTLS_ERR_ASN1_ALLOC_FAILED ) );
858
859 cur = cur->next;
860 }
861
862 buf = &( cur->buf );
863 buf->tag = policy_oid.tag;
864 buf->p = policy_oid.p;
865 buf->len = policy_oid.len;
866
867 *p += len;
868
869 /*
870 * If there is an optional qualifier, then *p < policy_end
871 * Check the Qualifier len to verify it doesn't exceed policy_end.
872 */
873 if( *p < policy_end )
874 {
875 if( ( ret = mbedtls_asn1_get_tag( p, policy_end, &len,
876 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
877 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
878 /*
879 * Skip the optional policy qualifiers.
880 */
881 *p += len;
882 }
883
884 if( *p != policy_end )
885 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
886 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
887 }
888
889 /* Set final sequence entry's next pointer to NULL */
890 cur->next = NULL;
891
892 if( *p != end )
893 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
894 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
895
896 return( parse_ret );
897 }
898
899 /*
900 * X.509 v3 extensions
901 *
902 */
x509_get_crt_ext(unsigned char ** p,const unsigned char * end,mbedtls_x509_crt * crt,mbedtls_x509_crt_ext_cb_t cb,void * p_ctx)903 static int x509_get_crt_ext( unsigned char **p,
904 const unsigned char *end,
905 mbedtls_x509_crt *crt,
906 mbedtls_x509_crt_ext_cb_t cb,
907 void *p_ctx )
908 {
909 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
910 size_t len;
911 unsigned char *end_ext_data, *start_ext_octet, *end_ext_octet;
912
913 if( *p == end )
914 return( 0 );
915
916 if( ( ret = mbedtls_x509_get_ext( p, end, &crt->v3_ext, 3 ) ) != 0 )
917 return( ret );
918
919 end = crt->v3_ext.p + crt->v3_ext.len;
920 while( *p < end )
921 {
922 /*
923 * Extension ::= SEQUENCE {
924 * extnID OBJECT IDENTIFIER,
925 * critical BOOLEAN DEFAULT FALSE,
926 * extnValue OCTET STRING }
927 */
928 mbedtls_x509_buf extn_oid = {0, 0, NULL};
929 int is_critical = 0; /* DEFAULT FALSE */
930 int ext_type = 0;
931
932 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
933 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
934 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
935
936 end_ext_data = *p + len;
937
938 /* Get extension ID */
939 if( ( ret = mbedtls_asn1_get_tag( p, end_ext_data, &extn_oid.len,
940 MBEDTLS_ASN1_OID ) ) != 0 )
941 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
942
943 extn_oid.tag = MBEDTLS_ASN1_OID;
944 extn_oid.p = *p;
945 *p += extn_oid.len;
946
947 /* Get optional critical */
948 if( ( ret = mbedtls_asn1_get_bool( p, end_ext_data, &is_critical ) ) != 0 &&
949 ( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) )
950 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
951
952 /* Data should be octet string type */
953 if( ( ret = mbedtls_asn1_get_tag( p, end_ext_data, &len,
954 MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
955 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
956
957 start_ext_octet = *p;
958 end_ext_octet = *p + len;
959
960 if( end_ext_octet != end_ext_data )
961 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
962 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
963
964 /*
965 * Detect supported extensions
966 */
967 ret = mbedtls_oid_get_x509_ext_type( &extn_oid, &ext_type );
968
969 if( ret != 0 )
970 {
971 /* Give the callback (if any) a chance to handle the extension */
972 if( cb != NULL )
973 {
974 ret = cb( p_ctx, crt, &extn_oid, is_critical, *p, end_ext_octet );
975 if( ret != 0 && is_critical )
976 return( ret );
977 *p = end_ext_octet;
978 continue;
979 }
980
981 /* No parser found, skip extension */
982 *p = end_ext_octet;
983
984 if( is_critical )
985 {
986 /* Data is marked as critical: fail */
987 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
988 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) );
989 }
990 continue;
991 }
992
993 /* Forbid repeated extensions */
994 if( ( crt->ext_types & ext_type ) != 0 )
995 return( MBEDTLS_ERR_X509_INVALID_EXTENSIONS );
996
997 crt->ext_types |= ext_type;
998
999 switch( ext_type )
1000 {
1001 case MBEDTLS_X509_EXT_BASIC_CONSTRAINTS:
1002 /* Parse basic constraints */
1003 if( ( ret = x509_get_basic_constraints( p, end_ext_octet,
1004 &crt->ca_istrue, &crt->max_pathlen ) ) != 0 )
1005 return( ret );
1006 break;
1007
1008 case MBEDTLS_X509_EXT_KEY_USAGE:
1009 /* Parse key usage */
1010 if( ( ret = x509_get_key_usage( p, end_ext_octet,
1011 &crt->key_usage ) ) != 0 )
1012 return( ret );
1013 break;
1014
1015 case MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE:
1016 /* Parse extended key usage */
1017 if( ( ret = x509_get_ext_key_usage( p, end_ext_octet,
1018 &crt->ext_key_usage ) ) != 0 )
1019 return( ret );
1020 break;
1021
1022 case MBEDTLS_X509_EXT_SUBJECT_ALT_NAME:
1023 /* Parse subject alt name */
1024 if( ( ret = x509_get_subject_alt_name( p, end_ext_octet,
1025 &crt->subject_alt_names ) ) != 0 )
1026 return( ret );
1027 break;
1028
1029 case MBEDTLS_X509_EXT_NS_CERT_TYPE:
1030 /* Parse netscape certificate type */
1031 if( ( ret = x509_get_ns_cert_type( p, end_ext_octet,
1032 &crt->ns_cert_type ) ) != 0 )
1033 return( ret );
1034 break;
1035
1036 case MBEDTLS_OID_X509_EXT_CERTIFICATE_POLICIES:
1037 /* Parse certificate policies type */
1038 if( ( ret = x509_get_certificate_policies( p, end_ext_octet,
1039 &crt->certificate_policies ) ) != 0 )
1040 {
1041 /* Give the callback (if any) a chance to handle the extension
1042 * if it contains unsupported policies */
1043 if( ret == MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE && cb != NULL &&
1044 cb( p_ctx, crt, &extn_oid, is_critical,
1045 start_ext_octet, end_ext_octet ) == 0 )
1046 break;
1047
1048 if( is_critical )
1049 return( ret );
1050 else
1051 /*
1052 * If MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE is returned, then we
1053 * cannot interpret or enforce the policy. However, it is up to
1054 * the user to choose how to enforce the policies,
1055 * unless the extension is critical.
1056 */
1057 if( ret != MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE )
1058 return( ret );
1059 }
1060 break;
1061
1062 default:
1063 /*
1064 * If this is a non-critical extension, which the oid layer
1065 * supports, but there isn't an x509 parser for it,
1066 * skip the extension.
1067 */
1068 if( is_critical )
1069 return( MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE );
1070 else
1071 *p = end_ext_octet;
1072 }
1073 }
1074
1075 if( *p != end )
1076 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
1077 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
1078
1079 return( 0 );
1080 }
1081
1082 /*
1083 * Parse and fill a single X.509 certificate in DER format
1084 */
x509_crt_parse_der_core(mbedtls_x509_crt * crt,const unsigned char * buf,size_t buflen,int make_copy,mbedtls_x509_crt_ext_cb_t cb,void * p_ctx)1085 static int x509_crt_parse_der_core( mbedtls_x509_crt *crt,
1086 const unsigned char *buf,
1087 size_t buflen,
1088 int make_copy,
1089 mbedtls_x509_crt_ext_cb_t cb,
1090 void *p_ctx )
1091 {
1092 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1093 size_t len;
1094 unsigned char *p, *end, *crt_end;
1095 mbedtls_x509_buf sig_params1, sig_params2, sig_oid2;
1096
1097 memset( &sig_params1, 0, sizeof( mbedtls_x509_buf ) );
1098 memset( &sig_params2, 0, sizeof( mbedtls_x509_buf ) );
1099 memset( &sig_oid2, 0, sizeof( mbedtls_x509_buf ) );
1100
1101 /*
1102 * Check for valid input
1103 */
1104 if( crt == NULL || buf == NULL )
1105 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1106
1107 /* Use the original buffer until we figure out actual length. */
1108 p = (unsigned char*) buf;
1109 len = buflen;
1110 end = p + len;
1111
1112 /*
1113 * Certificate ::= SEQUENCE {
1114 * tbsCertificate TBSCertificate,
1115 * signatureAlgorithm AlgorithmIdentifier,
1116 * signatureValue BIT STRING }
1117 */
1118 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
1119 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
1120 {
1121 mbedtls_x509_crt_free( crt );
1122 return( MBEDTLS_ERR_X509_INVALID_FORMAT );
1123 }
1124
1125 end = crt_end = p + len;
1126 crt->raw.len = crt_end - buf;
1127 if( make_copy != 0 )
1128 {
1129 /* Create and populate a new buffer for the raw field. */
1130 crt->raw.p = p = mbedtls_calloc( 1, crt->raw.len );
1131 if( crt->raw.p == NULL )
1132 return( MBEDTLS_ERR_X509_ALLOC_FAILED );
1133
1134 memcpy( crt->raw.p, buf, crt->raw.len );
1135 crt->own_buffer = 1;
1136
1137 p += crt->raw.len - len;
1138 end = crt_end = p + len;
1139 }
1140 else
1141 {
1142 crt->raw.p = (unsigned char*) buf;
1143 crt->own_buffer = 0;
1144 }
1145
1146 /*
1147 * TBSCertificate ::= SEQUENCE {
1148 */
1149 crt->tbs.p = p;
1150
1151 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
1152 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
1153 {
1154 mbedtls_x509_crt_free( crt );
1155 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_FORMAT, ret ) );
1156 }
1157
1158 end = p + len;
1159 crt->tbs.len = end - crt->tbs.p;
1160
1161 /*
1162 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
1163 *
1164 * CertificateSerialNumber ::= INTEGER
1165 *
1166 * signature AlgorithmIdentifier
1167 */
1168 if( ( ret = x509_get_version( &p, end, &crt->version ) ) != 0 ||
1169 ( ret = mbedtls_x509_get_serial( &p, end, &crt->serial ) ) != 0 ||
1170 ( ret = mbedtls_x509_get_alg( &p, end, &crt->sig_oid,
1171 &sig_params1 ) ) != 0 )
1172 {
1173 mbedtls_x509_crt_free( crt );
1174 return( ret );
1175 }
1176
1177 if( crt->version < 0 || crt->version > 2 )
1178 {
1179 mbedtls_x509_crt_free( crt );
1180 return( MBEDTLS_ERR_X509_UNKNOWN_VERSION );
1181 }
1182
1183 crt->version++;
1184
1185 if( ( ret = mbedtls_x509_get_sig_alg( &crt->sig_oid, &sig_params1,
1186 &crt->sig_md, &crt->sig_pk,
1187 &crt->sig_opts ) ) != 0 )
1188 {
1189 mbedtls_x509_crt_free( crt );
1190 return( ret );
1191 }
1192
1193 /*
1194 * issuer Name
1195 */
1196 crt->issuer_raw.p = p;
1197
1198 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
1199 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
1200 {
1201 mbedtls_x509_crt_free( crt );
1202 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_FORMAT, ret ) );
1203 }
1204
1205 if( ( ret = mbedtls_x509_get_name( &p, p + len, &crt->issuer ) ) != 0 )
1206 {
1207 mbedtls_x509_crt_free( crt );
1208 return( ret );
1209 }
1210
1211 crt->issuer_raw.len = p - crt->issuer_raw.p;
1212
1213 /*
1214 * Validity ::= SEQUENCE {
1215 * notBefore Time,
1216 * notAfter Time }
1217 *
1218 */
1219 if( ( ret = x509_get_dates( &p, end, &crt->valid_from,
1220 &crt->valid_to ) ) != 0 )
1221 {
1222 mbedtls_x509_crt_free( crt );
1223 return( ret );
1224 }
1225
1226 /*
1227 * subject Name
1228 */
1229 crt->subject_raw.p = p;
1230
1231 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
1232 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
1233 {
1234 mbedtls_x509_crt_free( crt );
1235 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_FORMAT, ret ) );
1236 }
1237
1238 if( len && ( ret = mbedtls_x509_get_name( &p, p + len, &crt->subject ) ) != 0 )
1239 {
1240 mbedtls_x509_crt_free( crt );
1241 return( ret );
1242 }
1243
1244 crt->subject_raw.len = p - crt->subject_raw.p;
1245
1246 /*
1247 * SubjectPublicKeyInfo
1248 */
1249 crt->pk_raw.p = p;
1250 if( ( ret = mbedtls_pk_parse_subpubkey( &p, end, &crt->pk ) ) != 0 )
1251 {
1252 mbedtls_x509_crt_free( crt );
1253 return( ret );
1254 }
1255 crt->pk_raw.len = p - crt->pk_raw.p;
1256
1257 /*
1258 * issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
1259 * -- If present, version shall be v2 or v3
1260 * subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
1261 * -- If present, version shall be v2 or v3
1262 * extensions [3] EXPLICIT Extensions OPTIONAL
1263 * -- If present, version shall be v3
1264 */
1265 if( crt->version == 2 || crt->version == 3 )
1266 {
1267 ret = x509_get_uid( &p, end, &crt->issuer_id, 1 );
1268 if( ret != 0 )
1269 {
1270 mbedtls_x509_crt_free( crt );
1271 return( ret );
1272 }
1273 }
1274
1275 if( crt->version == 2 || crt->version == 3 )
1276 {
1277 ret = x509_get_uid( &p, end, &crt->subject_id, 2 );
1278 if( ret != 0 )
1279 {
1280 mbedtls_x509_crt_free( crt );
1281 return( ret );
1282 }
1283 }
1284
1285 if( crt->version == 3 )
1286 {
1287 ret = x509_get_crt_ext( &p, end, crt, cb, p_ctx );
1288 if( ret != 0 )
1289 {
1290 mbedtls_x509_crt_free( crt );
1291 return( ret );
1292 }
1293 }
1294
1295 if( p != end )
1296 {
1297 mbedtls_x509_crt_free( crt );
1298 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_FORMAT,
1299 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
1300 }
1301
1302 end = crt_end;
1303
1304 /*
1305 * }
1306 * -- end of TBSCertificate
1307 *
1308 * signatureAlgorithm AlgorithmIdentifier,
1309 * signatureValue BIT STRING
1310 */
1311 if( ( ret = mbedtls_x509_get_alg( &p, end, &sig_oid2, &sig_params2 ) ) != 0 )
1312 {
1313 mbedtls_x509_crt_free( crt );
1314 return( ret );
1315 }
1316
1317 if( crt->sig_oid.len != sig_oid2.len ||
1318 memcmp( crt->sig_oid.p, sig_oid2.p, crt->sig_oid.len ) != 0 ||
1319 sig_params1.tag != sig_params2.tag ||
1320 sig_params1.len != sig_params2.len ||
1321 ( sig_params1.len != 0 &&
1322 memcmp( sig_params1.p, sig_params2.p, sig_params1.len ) != 0 ) )
1323 {
1324 mbedtls_x509_crt_free( crt );
1325 return( MBEDTLS_ERR_X509_SIG_MISMATCH );
1326 }
1327
1328 if( ( ret = mbedtls_x509_get_sig( &p, end, &crt->sig ) ) != 0 )
1329 {
1330 mbedtls_x509_crt_free( crt );
1331 return( ret );
1332 }
1333
1334 if( p != end )
1335 {
1336 mbedtls_x509_crt_free( crt );
1337 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_FORMAT,
1338 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
1339 }
1340
1341 return( 0 );
1342 }
1343
1344 /*
1345 * Parse one X.509 certificate in DER format from a buffer and add them to a
1346 * chained list
1347 */
mbedtls_x509_crt_parse_der_internal(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen,int make_copy,mbedtls_x509_crt_ext_cb_t cb,void * p_ctx)1348 static int mbedtls_x509_crt_parse_der_internal( mbedtls_x509_crt *chain,
1349 const unsigned char *buf,
1350 size_t buflen,
1351 int make_copy,
1352 mbedtls_x509_crt_ext_cb_t cb,
1353 void *p_ctx )
1354 {
1355 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1356 mbedtls_x509_crt *crt = chain, *prev = NULL;
1357
1358 /*
1359 * Check for valid input
1360 */
1361 if( crt == NULL || buf == NULL )
1362 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1363
1364 while( crt->version != 0 && crt->next != NULL )
1365 {
1366 prev = crt;
1367 crt = crt->next;
1368 }
1369
1370 /*
1371 * Add new certificate on the end of the chain if needed.
1372 */
1373 if( crt->version != 0 && crt->next == NULL )
1374 {
1375 crt->next = mbedtls_calloc( 1, sizeof( mbedtls_x509_crt ) );
1376
1377 if( crt->next == NULL )
1378 return( MBEDTLS_ERR_X509_ALLOC_FAILED );
1379
1380 prev = crt;
1381 mbedtls_x509_crt_init( crt->next );
1382 crt = crt->next;
1383 }
1384
1385 ret = x509_crt_parse_der_core( crt, buf, buflen, make_copy, cb, p_ctx );
1386 if( ret != 0 )
1387 {
1388 if( prev )
1389 prev->next = NULL;
1390
1391 if( crt != chain )
1392 mbedtls_free( crt );
1393
1394 return( ret );
1395 }
1396
1397 return( 0 );
1398 }
1399
mbedtls_x509_crt_parse_der_nocopy(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)1400 int mbedtls_x509_crt_parse_der_nocopy( mbedtls_x509_crt *chain,
1401 const unsigned char *buf,
1402 size_t buflen )
1403 {
1404 return( mbedtls_x509_crt_parse_der_internal( chain, buf, buflen, 0, NULL, NULL ) );
1405 }
1406
mbedtls_x509_crt_parse_der_with_ext_cb(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen,int make_copy,mbedtls_x509_crt_ext_cb_t cb,void * p_ctx)1407 int mbedtls_x509_crt_parse_der_with_ext_cb( mbedtls_x509_crt *chain,
1408 const unsigned char *buf,
1409 size_t buflen,
1410 int make_copy,
1411 mbedtls_x509_crt_ext_cb_t cb,
1412 void *p_ctx )
1413 {
1414 return( mbedtls_x509_crt_parse_der_internal( chain, buf, buflen, make_copy, cb, p_ctx ) );
1415 }
1416
mbedtls_x509_crt_parse_der(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)1417 int mbedtls_x509_crt_parse_der( mbedtls_x509_crt *chain,
1418 const unsigned char *buf,
1419 size_t buflen )
1420 {
1421 return( mbedtls_x509_crt_parse_der_internal( chain, buf, buflen, 1, NULL, NULL ) );
1422 }
1423
1424 /*
1425 * Parse one or more PEM certificates from a buffer and add them to the chained
1426 * list
1427 */
mbedtls_x509_crt_parse(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)1428 int mbedtls_x509_crt_parse( mbedtls_x509_crt *chain,
1429 const unsigned char *buf,
1430 size_t buflen )
1431 {
1432 #if defined(MBEDTLS_PEM_PARSE_C)
1433 int success = 0, first_error = 0, total_failed = 0;
1434 int buf_format = MBEDTLS_X509_FORMAT_DER;
1435 #endif
1436
1437 /*
1438 * Check for valid input
1439 */
1440 if( chain == NULL || buf == NULL )
1441 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1442
1443 /*
1444 * Determine buffer content. Buffer contains either one DER certificate or
1445 * one or more PEM certificates.
1446 */
1447 #if defined(MBEDTLS_PEM_PARSE_C)
1448 if( buflen != 0 && buf[buflen - 1] == '\0' &&
1449 strstr( (const char *) buf, "-----BEGIN CERTIFICATE-----" ) != NULL )
1450 {
1451 buf_format = MBEDTLS_X509_FORMAT_PEM;
1452 }
1453
1454 if( buf_format == MBEDTLS_X509_FORMAT_DER )
1455 return mbedtls_x509_crt_parse_der( chain, buf, buflen );
1456 #else
1457 return mbedtls_x509_crt_parse_der( chain, buf, buflen );
1458 #endif
1459
1460 #if defined(MBEDTLS_PEM_PARSE_C)
1461 if( buf_format == MBEDTLS_X509_FORMAT_PEM )
1462 {
1463 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1464 mbedtls_pem_context pem;
1465
1466 /* 1 rather than 0 since the terminating NULL byte is counted in */
1467 while( buflen > 1 )
1468 {
1469 size_t use_len;
1470 mbedtls_pem_init( &pem );
1471
1472 /* If we get there, we know the string is null-terminated */
1473 ret = mbedtls_pem_read_buffer( &pem,
1474 "-----BEGIN CERTIFICATE-----",
1475 "-----END CERTIFICATE-----",
1476 buf, NULL, 0, &use_len );
1477
1478 if( ret == 0 )
1479 {
1480 /*
1481 * Was PEM encoded
1482 */
1483 buflen -= use_len;
1484 buf += use_len;
1485 }
1486 else if( ret == MBEDTLS_ERR_PEM_BAD_INPUT_DATA )
1487 {
1488 return( ret );
1489 }
1490 else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
1491 {
1492 mbedtls_pem_free( &pem );
1493
1494 /*
1495 * PEM header and footer were found
1496 */
1497 buflen -= use_len;
1498 buf += use_len;
1499
1500 if( first_error == 0 )
1501 first_error = ret;
1502
1503 total_failed++;
1504 continue;
1505 }
1506 else
1507 break;
1508
1509 ret = mbedtls_x509_crt_parse_der( chain, pem.buf, pem.buflen );
1510
1511 mbedtls_pem_free( &pem );
1512
1513 if( ret != 0 )
1514 {
1515 /*
1516 * Quit parsing on a memory error
1517 */
1518 if( ret == MBEDTLS_ERR_X509_ALLOC_FAILED )
1519 return( ret );
1520
1521 if( first_error == 0 )
1522 first_error = ret;
1523
1524 total_failed++;
1525 continue;
1526 }
1527
1528 success = 1;
1529 }
1530 }
1531
1532 if( success )
1533 return( total_failed );
1534 else if( first_error )
1535 return( first_error );
1536 else
1537 return( MBEDTLS_ERR_X509_CERT_UNKNOWN_FORMAT );
1538 #endif /* MBEDTLS_PEM_PARSE_C */
1539 }
1540
1541 #if defined(MBEDTLS_FS_IO)
1542 /*
1543 * Load one or more certificates and add them to the chained list
1544 */
mbedtls_x509_crt_parse_file(mbedtls_x509_crt * chain,const char * path)1545 int mbedtls_x509_crt_parse_file( mbedtls_x509_crt *chain, const char *path )
1546 {
1547 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1548 size_t n;
1549 unsigned char *buf;
1550
1551 if( ( ret = mbedtls_pk_load_file( path, &buf, &n ) ) != 0 )
1552 return( ret );
1553
1554 ret = mbedtls_x509_crt_parse( chain, buf, n );
1555
1556 mbedtls_platform_zeroize( buf, n );
1557 mbedtls_free( buf );
1558
1559 return( ret );
1560 }
1561
mbedtls_x509_crt_parse_path(mbedtls_x509_crt * chain,const char * path)1562 int mbedtls_x509_crt_parse_path( mbedtls_x509_crt *chain, const char *path )
1563 {
1564 int ret = 0;
1565 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
1566 int w_ret;
1567 WCHAR szDir[MAX_PATH];
1568 char filename[MAX_PATH];
1569 char *p;
1570 size_t len = strlen( path );
1571
1572 WIN32_FIND_DATAW file_data;
1573 HANDLE hFind;
1574
1575 if( len > MAX_PATH - 3 )
1576 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1577
1578 memset( szDir, 0, sizeof(szDir) );
1579 memset( filename, 0, MAX_PATH );
1580 memcpy( filename, path, len );
1581 filename[len++] = '\\';
1582 p = filename + len;
1583 filename[len++] = '*';
1584
1585 w_ret = MultiByteToWideChar( CP_ACP, 0, filename, (int)len, szDir,
1586 MAX_PATH - 3 );
1587 if( w_ret == 0 )
1588 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1589
1590 hFind = FindFirstFileW( szDir, &file_data );
1591 if( hFind == INVALID_HANDLE_VALUE )
1592 return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
1593
1594 len = MAX_PATH - len;
1595 do
1596 {
1597 memset( p, 0, len );
1598
1599 if( file_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY )
1600 continue;
1601
1602 w_ret = WideCharToMultiByte( CP_ACP, 0, file_data.cFileName,
1603 lstrlenW( file_data.cFileName ),
1604 p, (int) len - 1,
1605 NULL, NULL );
1606 if( w_ret == 0 )
1607 {
1608 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1609 goto cleanup;
1610 }
1611
1612 w_ret = mbedtls_x509_crt_parse_file( chain, filename );
1613 if( w_ret < 0 )
1614 ret++;
1615 else
1616 ret += w_ret;
1617 }
1618 while( FindNextFileW( hFind, &file_data ) != 0 );
1619
1620 if( GetLastError() != ERROR_NO_MORE_FILES )
1621 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1622
1623 cleanup:
1624 FindClose( hFind );
1625 #else /* _WIN32 */
1626 int t_ret;
1627 int snp_ret;
1628 struct stat sb;
1629 struct dirent *entry;
1630 char entry_name[MBEDTLS_X509_MAX_FILE_PATH_LEN];
1631 DIR *dir = opendir( path );
1632
1633 if( dir == NULL )
1634 return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
1635
1636 #if defined(MBEDTLS_THREADING_C)
1637 if( ( ret = mbedtls_mutex_lock( &mbedtls_threading_readdir_mutex ) ) != 0 )
1638 {
1639 closedir( dir );
1640 return( ret );
1641 }
1642 #endif /* MBEDTLS_THREADING_C */
1643
1644 memset( &sb, 0, sizeof( sb ) );
1645
1646 while( ( entry = readdir( dir ) ) != NULL )
1647 {
1648 snp_ret = mbedtls_snprintf( entry_name, sizeof entry_name,
1649 "%s/%s", path, entry->d_name );
1650
1651 if( snp_ret < 0 || (size_t)snp_ret >= sizeof entry_name )
1652 {
1653 ret = MBEDTLS_ERR_X509_BUFFER_TOO_SMALL;
1654 goto cleanup;
1655 }
1656 else if( stat( entry_name, &sb ) == -1 )
1657 {
1658 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1659 goto cleanup;
1660 }
1661
1662 if( !S_ISREG( sb.st_mode ) )
1663 continue;
1664
1665 // Ignore parse errors
1666 //
1667 t_ret = mbedtls_x509_crt_parse_file( chain, entry_name );
1668 if( t_ret < 0 )
1669 ret++;
1670 else
1671 ret += t_ret;
1672 }
1673
1674 cleanup:
1675 closedir( dir );
1676
1677 #if defined(MBEDTLS_THREADING_C)
1678 if( mbedtls_mutex_unlock( &mbedtls_threading_readdir_mutex ) != 0 )
1679 ret = MBEDTLS_ERR_THREADING_MUTEX_ERROR;
1680 #endif /* MBEDTLS_THREADING_C */
1681
1682 #endif /* _WIN32 */
1683
1684 return( ret );
1685 }
1686 #endif /* MBEDTLS_FS_IO */
1687
1688 /*
1689 * OtherName ::= SEQUENCE {
1690 * type-id OBJECT IDENTIFIER,
1691 * value [0] EXPLICIT ANY DEFINED BY type-id }
1692 *
1693 * HardwareModuleName ::= SEQUENCE {
1694 * hwType OBJECT IDENTIFIER,
1695 * hwSerialNum OCTET STRING }
1696 *
1697 * NOTE: we currently only parse and use otherName of type HwModuleName,
1698 * as defined in RFC 4108.
1699 */
x509_get_other_name(const mbedtls_x509_buf * subject_alt_name,mbedtls_x509_san_other_name * other_name)1700 static int x509_get_other_name( const mbedtls_x509_buf *subject_alt_name,
1701 mbedtls_x509_san_other_name *other_name )
1702 {
1703 int ret = 0;
1704 size_t len;
1705 unsigned char *p = subject_alt_name->p;
1706 const unsigned char *end = p + subject_alt_name->len;
1707 mbedtls_x509_buf cur_oid;
1708
1709 if( ( subject_alt_name->tag &
1710 ( MBEDTLS_ASN1_TAG_CLASS_MASK | MBEDTLS_ASN1_TAG_VALUE_MASK ) ) !=
1711 ( MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_X509_SAN_OTHER_NAME ) )
1712 {
1713 /*
1714 * The given subject alternative name is not of type "othername".
1715 */
1716 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
1717 }
1718
1719 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
1720 MBEDTLS_ASN1_OID ) ) != 0 )
1721 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
1722
1723 cur_oid.tag = MBEDTLS_ASN1_OID;
1724 cur_oid.p = p;
1725 cur_oid.len = len;
1726
1727 /*
1728 * Only HwModuleName is currently supported.
1729 */
1730 if( MBEDTLS_OID_CMP( MBEDTLS_OID_ON_HW_MODULE_NAME, &cur_oid ) != 0 )
1731 {
1732 return( MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE );
1733 }
1734
1735 if( p + len >= end )
1736 {
1737 mbedtls_platform_zeroize( other_name, sizeof( *other_name ) );
1738 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
1739 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
1740 }
1741 p += len;
1742 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
1743 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_CONTEXT_SPECIFIC ) ) != 0 )
1744 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
1745
1746 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
1747 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
1748 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
1749
1750 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len, MBEDTLS_ASN1_OID ) ) != 0 )
1751 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
1752
1753 other_name->value.hardware_module_name.oid.tag = MBEDTLS_ASN1_OID;
1754 other_name->value.hardware_module_name.oid.p = p;
1755 other_name->value.hardware_module_name.oid.len = len;
1756
1757 if( p + len >= end )
1758 {
1759 mbedtls_platform_zeroize( other_name, sizeof( *other_name ) );
1760 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
1761 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
1762 }
1763 p += len;
1764 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
1765 MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
1766 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret ) );
1767
1768 other_name->value.hardware_module_name.val.tag = MBEDTLS_ASN1_OCTET_STRING;
1769 other_name->value.hardware_module_name.val.p = p;
1770 other_name->value.hardware_module_name.val.len = len;
1771 p += len;
1772 if( p != end )
1773 {
1774 mbedtls_platform_zeroize( other_name,
1775 sizeof( *other_name ) );
1776 return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
1777 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
1778 }
1779 return( 0 );
1780 }
1781
mbedtls_x509_parse_subject_alt_name(const mbedtls_x509_buf * san_buf,mbedtls_x509_subject_alternative_name * san)1782 int mbedtls_x509_parse_subject_alt_name( const mbedtls_x509_buf *san_buf,
1783 mbedtls_x509_subject_alternative_name *san )
1784 {
1785 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1786 switch( san_buf->tag &
1787 ( MBEDTLS_ASN1_TAG_CLASS_MASK |
1788 MBEDTLS_ASN1_TAG_VALUE_MASK ) )
1789 {
1790 /*
1791 * otherName
1792 */
1793 case( MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_X509_SAN_OTHER_NAME ):
1794 {
1795 mbedtls_x509_san_other_name other_name;
1796
1797 ret = x509_get_other_name( san_buf, &other_name );
1798 if( ret != 0 )
1799 return( ret );
1800
1801 memset( san, 0, sizeof( mbedtls_x509_subject_alternative_name ) );
1802 san->type = MBEDTLS_X509_SAN_OTHER_NAME;
1803 memcpy( &san->san.other_name,
1804 &other_name, sizeof( other_name ) );
1805
1806 }
1807 break;
1808
1809 /*
1810 * dNSName
1811 */
1812 case( MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_X509_SAN_DNS_NAME ):
1813 {
1814 memset( san, 0, sizeof( mbedtls_x509_subject_alternative_name ) );
1815 san->type = MBEDTLS_X509_SAN_DNS_NAME;
1816
1817 memcpy( &san->san.unstructured_name,
1818 san_buf, sizeof( *san_buf ) );
1819
1820 }
1821 break;
1822
1823 /*
1824 * Type not supported
1825 */
1826 default:
1827 return( MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE );
1828 }
1829 return( 0 );
1830 }
1831
1832 #if !defined(MBEDTLS_X509_REMOVE_INFO)
x509_info_subject_alt_name(char ** buf,size_t * size,const mbedtls_x509_sequence * subject_alt_name,const char * prefix)1833 static int x509_info_subject_alt_name( char **buf, size_t *size,
1834 const mbedtls_x509_sequence
1835 *subject_alt_name,
1836 const char *prefix )
1837 {
1838 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1839 size_t n = *size;
1840 char *p = *buf;
1841 const mbedtls_x509_sequence *cur = subject_alt_name;
1842 mbedtls_x509_subject_alternative_name san;
1843 int parse_ret;
1844
1845 while( cur != NULL )
1846 {
1847 memset( &san, 0, sizeof( san ) );
1848 parse_ret = mbedtls_x509_parse_subject_alt_name( &cur->buf, &san );
1849 if( parse_ret != 0 )
1850 {
1851 if( parse_ret == MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE )
1852 {
1853 ret = mbedtls_snprintf( p, n, "\n%s <unsupported>", prefix );
1854 MBEDTLS_X509_SAFE_SNPRINTF;
1855 }
1856 else
1857 {
1858 ret = mbedtls_snprintf( p, n, "\n%s <malformed>", prefix );
1859 MBEDTLS_X509_SAFE_SNPRINTF;
1860 }
1861 cur = cur->next;
1862 continue;
1863 }
1864
1865 switch( san.type )
1866 {
1867 /*
1868 * otherName
1869 */
1870 case MBEDTLS_X509_SAN_OTHER_NAME:
1871 {
1872 mbedtls_x509_san_other_name *other_name = &san.san.other_name;
1873
1874 ret = mbedtls_snprintf( p, n, "\n%s otherName :", prefix );
1875 MBEDTLS_X509_SAFE_SNPRINTF;
1876
1877 if( MBEDTLS_OID_CMP( MBEDTLS_OID_ON_HW_MODULE_NAME,
1878 &other_name->value.hardware_module_name.oid ) != 0 )
1879 {
1880 ret = mbedtls_snprintf( p, n, "\n%s hardware module name :", prefix );
1881 MBEDTLS_X509_SAFE_SNPRINTF;
1882 ret = mbedtls_snprintf( p, n, "\n%s hardware type : ", prefix );
1883 MBEDTLS_X509_SAFE_SNPRINTF;
1884
1885 ret = mbedtls_oid_get_numeric_string( p, n, &other_name->value.hardware_module_name.oid );
1886 MBEDTLS_X509_SAFE_SNPRINTF;
1887
1888 ret = mbedtls_snprintf( p, n, "\n%s hardware serial number : ", prefix );
1889 MBEDTLS_X509_SAFE_SNPRINTF;
1890
1891 if( other_name->value.hardware_module_name.val.len >= n )
1892 {
1893 *p = '\0';
1894 return( MBEDTLS_ERR_X509_BUFFER_TOO_SMALL );
1895 }
1896
1897 memcpy( p, other_name->value.hardware_module_name.val.p,
1898 other_name->value.hardware_module_name.val.len );
1899 p += other_name->value.hardware_module_name.val.len;
1900
1901 n -= other_name->value.hardware_module_name.val.len;
1902
1903 }/* MBEDTLS_OID_ON_HW_MODULE_NAME */
1904 }
1905 break;
1906
1907 /*
1908 * dNSName
1909 */
1910 case MBEDTLS_X509_SAN_DNS_NAME:
1911 {
1912 ret = mbedtls_snprintf( p, n, "\n%s dNSName : ", prefix );
1913 MBEDTLS_X509_SAFE_SNPRINTF;
1914 if( san.san.unstructured_name.len >= n )
1915 {
1916 *p = '\0';
1917 return( MBEDTLS_ERR_X509_BUFFER_TOO_SMALL );
1918 }
1919
1920 memcpy( p, san.san.unstructured_name.p, san.san.unstructured_name.len );
1921 p += san.san.unstructured_name.len;
1922 n -= san.san.unstructured_name.len;
1923 }
1924 break;
1925
1926 /*
1927 * Type not supported, skip item.
1928 */
1929 default:
1930 ret = mbedtls_snprintf( p, n, "\n%s <unsupported>", prefix );
1931 MBEDTLS_X509_SAFE_SNPRINTF;
1932 break;
1933 }
1934
1935 cur = cur->next;
1936 }
1937
1938 *p = '\0';
1939
1940 *size = n;
1941 *buf = p;
1942
1943 return( 0 );
1944 }
1945
1946 #define PRINT_ITEM(i) \
1947 { \
1948 ret = mbedtls_snprintf( p, n, "%s" i, sep ); \
1949 MBEDTLS_X509_SAFE_SNPRINTF; \
1950 sep = ", "; \
1951 }
1952
1953 #define CERT_TYPE(type,name) \
1954 if( ns_cert_type & (type) ) \
1955 PRINT_ITEM( name );
1956
x509_info_cert_type(char ** buf,size_t * size,unsigned char ns_cert_type)1957 static int x509_info_cert_type( char **buf, size_t *size,
1958 unsigned char ns_cert_type )
1959 {
1960 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1961 size_t n = *size;
1962 char *p = *buf;
1963 const char *sep = "";
1964
1965 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_CLIENT, "SSL Client" );
1966 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_SERVER, "SSL Server" );
1967 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_EMAIL, "Email" );
1968 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING, "Object Signing" );
1969 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_RESERVED, "Reserved" );
1970 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_SSL_CA, "SSL CA" );
1971 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_EMAIL_CA, "Email CA" );
1972 CERT_TYPE( MBEDTLS_X509_NS_CERT_TYPE_OBJECT_SIGNING_CA, "Object Signing CA" );
1973
1974 *size = n;
1975 *buf = p;
1976
1977 return( 0 );
1978 }
1979
1980 #define KEY_USAGE(code,name) \
1981 if( key_usage & (code) ) \
1982 PRINT_ITEM( name );
1983
x509_info_key_usage(char ** buf,size_t * size,unsigned int key_usage)1984 static int x509_info_key_usage( char **buf, size_t *size,
1985 unsigned int key_usage )
1986 {
1987 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1988 size_t n = *size;
1989 char *p = *buf;
1990 const char *sep = "";
1991
1992 KEY_USAGE( MBEDTLS_X509_KU_DIGITAL_SIGNATURE, "Digital Signature" );
1993 KEY_USAGE( MBEDTLS_X509_KU_NON_REPUDIATION, "Non Repudiation" );
1994 KEY_USAGE( MBEDTLS_X509_KU_KEY_ENCIPHERMENT, "Key Encipherment" );
1995 KEY_USAGE( MBEDTLS_X509_KU_DATA_ENCIPHERMENT, "Data Encipherment" );
1996 KEY_USAGE( MBEDTLS_X509_KU_KEY_AGREEMENT, "Key Agreement" );
1997 KEY_USAGE( MBEDTLS_X509_KU_KEY_CERT_SIGN, "Key Cert Sign" );
1998 KEY_USAGE( MBEDTLS_X509_KU_CRL_SIGN, "CRL Sign" );
1999 KEY_USAGE( MBEDTLS_X509_KU_ENCIPHER_ONLY, "Encipher Only" );
2000 KEY_USAGE( MBEDTLS_X509_KU_DECIPHER_ONLY, "Decipher Only" );
2001
2002 *size = n;
2003 *buf = p;
2004
2005 return( 0 );
2006 }
2007
x509_info_ext_key_usage(char ** buf,size_t * size,const mbedtls_x509_sequence * extended_key_usage)2008 static int x509_info_ext_key_usage( char **buf, size_t *size,
2009 const mbedtls_x509_sequence *extended_key_usage )
2010 {
2011 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
2012 const char *desc;
2013 size_t n = *size;
2014 char *p = *buf;
2015 const mbedtls_x509_sequence *cur = extended_key_usage;
2016 const char *sep = "";
2017
2018 while( cur != NULL )
2019 {
2020 if( mbedtls_oid_get_extended_key_usage( &cur->buf, &desc ) != 0 )
2021 desc = "???";
2022
2023 ret = mbedtls_snprintf( p, n, "%s%s", sep, desc );
2024 MBEDTLS_X509_SAFE_SNPRINTF;
2025
2026 sep = ", ";
2027
2028 cur = cur->next;
2029 }
2030
2031 *size = n;
2032 *buf = p;
2033
2034 return( 0 );
2035 }
2036
x509_info_cert_policies(char ** buf,size_t * size,const mbedtls_x509_sequence * certificate_policies)2037 static int x509_info_cert_policies( char **buf, size_t *size,
2038 const mbedtls_x509_sequence *certificate_policies )
2039 {
2040 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
2041 const char *desc;
2042 size_t n = *size;
2043 char *p = *buf;
2044 const mbedtls_x509_sequence *cur = certificate_policies;
2045 const char *sep = "";
2046
2047 while( cur != NULL )
2048 {
2049 if( mbedtls_oid_get_certificate_policies( &cur->buf, &desc ) != 0 )
2050 desc = "???";
2051
2052 ret = mbedtls_snprintf( p, n, "%s%s", sep, desc );
2053 MBEDTLS_X509_SAFE_SNPRINTF;
2054
2055 sep = ", ";
2056
2057 cur = cur->next;
2058 }
2059
2060 *size = n;
2061 *buf = p;
2062
2063 return( 0 );
2064 }
2065
2066 /*
2067 * Return an informational string about the certificate.
2068 */
2069 #define BEFORE_COLON 18
2070 #define BC "18"
mbedtls_x509_crt_info(char * buf,size_t size,const char * prefix,const mbedtls_x509_crt * crt)2071 int mbedtls_x509_crt_info( char *buf, size_t size, const char *prefix,
2072 const mbedtls_x509_crt *crt )
2073 {
2074 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
2075 size_t n;
2076 char *p;
2077 char key_size_str[BEFORE_COLON];
2078
2079 p = buf;
2080 n = size;
2081
2082 if( NULL == crt )
2083 {
2084 ret = mbedtls_snprintf( p, n, "\nCertificate is uninitialised!\n" );
2085 MBEDTLS_X509_SAFE_SNPRINTF;
2086
2087 return( (int) ( size - n ) );
2088 }
2089
2090 ret = mbedtls_snprintf( p, n, "%scert. version : %d\n",
2091 prefix, crt->version );
2092 MBEDTLS_X509_SAFE_SNPRINTF;
2093 ret = mbedtls_snprintf( p, n, "%sserial number : ",
2094 prefix );
2095 MBEDTLS_X509_SAFE_SNPRINTF;
2096
2097 ret = mbedtls_x509_serial_gets( p, n, &crt->serial );
2098 MBEDTLS_X509_SAFE_SNPRINTF;
2099
2100 ret = mbedtls_snprintf( p, n, "\n%sissuer name : ", prefix );
2101 MBEDTLS_X509_SAFE_SNPRINTF;
2102 ret = mbedtls_x509_dn_gets( p, n, &crt->issuer );
2103 MBEDTLS_X509_SAFE_SNPRINTF;
2104
2105 ret = mbedtls_snprintf( p, n, "\n%ssubject name : ", prefix );
2106 MBEDTLS_X509_SAFE_SNPRINTF;
2107 ret = mbedtls_x509_dn_gets( p, n, &crt->subject );
2108 MBEDTLS_X509_SAFE_SNPRINTF;
2109
2110 ret = mbedtls_snprintf( p, n, "\n%sissued on : " \
2111 "%04d-%02d-%02d %02d:%02d:%02d", prefix,
2112 crt->valid_from.year, crt->valid_from.mon,
2113 crt->valid_from.day, crt->valid_from.hour,
2114 crt->valid_from.min, crt->valid_from.sec );
2115 MBEDTLS_X509_SAFE_SNPRINTF;
2116
2117 ret = mbedtls_snprintf( p, n, "\n%sexpires on : " \
2118 "%04d-%02d-%02d %02d:%02d:%02d", prefix,
2119 crt->valid_to.year, crt->valid_to.mon,
2120 crt->valid_to.day, crt->valid_to.hour,
2121 crt->valid_to.min, crt->valid_to.sec );
2122 MBEDTLS_X509_SAFE_SNPRINTF;
2123
2124 ret = mbedtls_snprintf( p, n, "\n%ssigned using : ", prefix );
2125 MBEDTLS_X509_SAFE_SNPRINTF;
2126
2127 ret = mbedtls_x509_sig_alg_gets( p, n, &crt->sig_oid, crt->sig_pk,
2128 crt->sig_md, crt->sig_opts );
2129 MBEDTLS_X509_SAFE_SNPRINTF;
2130
2131 /* Key size */
2132 if( ( ret = mbedtls_x509_key_size_helper( key_size_str, BEFORE_COLON,
2133 mbedtls_pk_get_name( &crt->pk ) ) ) != 0 )
2134 {
2135 return( ret );
2136 }
2137
2138 ret = mbedtls_snprintf( p, n, "\n%s%-" BC "s: %d bits", prefix, key_size_str,
2139 (int) mbedtls_pk_get_bitlen( &crt->pk ) );
2140 MBEDTLS_X509_SAFE_SNPRINTF;
2141
2142 /*
2143 * Optional extensions
2144 */
2145
2146 if( crt->ext_types & MBEDTLS_X509_EXT_BASIC_CONSTRAINTS )
2147 {
2148 ret = mbedtls_snprintf( p, n, "\n%sbasic constraints : CA=%s", prefix,
2149 crt->ca_istrue ? "true" : "false" );
2150 MBEDTLS_X509_SAFE_SNPRINTF;
2151
2152 if( crt->max_pathlen > 0 )
2153 {
2154 ret = mbedtls_snprintf( p, n, ", max_pathlen=%d", crt->max_pathlen - 1 );
2155 MBEDTLS_X509_SAFE_SNPRINTF;
2156 }
2157 }
2158
2159 if( crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME )
2160 {
2161 ret = mbedtls_snprintf( p, n, "\n%ssubject alt name :", prefix );
2162 MBEDTLS_X509_SAFE_SNPRINTF;
2163
2164 if( ( ret = x509_info_subject_alt_name( &p, &n,
2165 &crt->subject_alt_names,
2166 prefix ) ) != 0 )
2167 return( ret );
2168 }
2169
2170 if( crt->ext_types & MBEDTLS_X509_EXT_NS_CERT_TYPE )
2171 {
2172 ret = mbedtls_snprintf( p, n, "\n%scert. type : ", prefix );
2173 MBEDTLS_X509_SAFE_SNPRINTF;
2174
2175 if( ( ret = x509_info_cert_type( &p, &n, crt->ns_cert_type ) ) != 0 )
2176 return( ret );
2177 }
2178
2179 if( crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE )
2180 {
2181 ret = mbedtls_snprintf( p, n, "\n%skey usage : ", prefix );
2182 MBEDTLS_X509_SAFE_SNPRINTF;
2183
2184 if( ( ret = x509_info_key_usage( &p, &n, crt->key_usage ) ) != 0 )
2185 return( ret );
2186 }
2187
2188 if( crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE )
2189 {
2190 ret = mbedtls_snprintf( p, n, "\n%sext key usage : ", prefix );
2191 MBEDTLS_X509_SAFE_SNPRINTF;
2192
2193 if( ( ret = x509_info_ext_key_usage( &p, &n,
2194 &crt->ext_key_usage ) ) != 0 )
2195 return( ret );
2196 }
2197
2198 if( crt->ext_types & MBEDTLS_OID_X509_EXT_CERTIFICATE_POLICIES )
2199 {
2200 ret = mbedtls_snprintf( p, n, "\n%scertificate policies : ", prefix );
2201 MBEDTLS_X509_SAFE_SNPRINTF;
2202
2203 if( ( ret = x509_info_cert_policies( &p, &n,
2204 &crt->certificate_policies ) ) != 0 )
2205 return( ret );
2206 }
2207
2208 ret = mbedtls_snprintf( p, n, "\n" );
2209 MBEDTLS_X509_SAFE_SNPRINTF;
2210
2211 return( (int) ( size - n ) );
2212 }
2213
2214 struct x509_crt_verify_string {
2215 int code;
2216 const char *string;
2217 };
2218
2219 #define X509_CRT_ERROR_INFO( err, err_str, info ) { err, info },
2220 static const struct x509_crt_verify_string x509_crt_verify_strings[] = {
2221 MBEDTLS_X509_CRT_ERROR_INFO_LIST
2222 { 0, NULL }
2223 };
2224 #undef X509_CRT_ERROR_INFO
2225
mbedtls_x509_crt_verify_info(char * buf,size_t size,const char * prefix,uint32_t flags)2226 int mbedtls_x509_crt_verify_info( char *buf, size_t size, const char *prefix,
2227 uint32_t flags )
2228 {
2229 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
2230 const struct x509_crt_verify_string *cur;
2231 char *p = buf;
2232 size_t n = size;
2233
2234 for( cur = x509_crt_verify_strings; cur->string != NULL ; cur++ )
2235 {
2236 if( ( flags & cur->code ) == 0 )
2237 continue;
2238
2239 ret = mbedtls_snprintf( p, n, "%s%s\n", prefix, cur->string );
2240 MBEDTLS_X509_SAFE_SNPRINTF;
2241 flags ^= cur->code;
2242 }
2243
2244 if( flags != 0 )
2245 {
2246 ret = mbedtls_snprintf( p, n, "%sUnknown reason "
2247 "(this should not happen)\n", prefix );
2248 MBEDTLS_X509_SAFE_SNPRINTF;
2249 }
2250
2251 return( (int) ( size - n ) );
2252 }
2253 #endif /* MBEDTLS_X509_REMOVE_INFO */
2254
mbedtls_x509_crt_check_key_usage(const mbedtls_x509_crt * crt,unsigned int usage)2255 int mbedtls_x509_crt_check_key_usage( const mbedtls_x509_crt *crt,
2256 unsigned int usage )
2257 {
2258 unsigned int usage_must, usage_may;
2259 unsigned int may_mask = MBEDTLS_X509_KU_ENCIPHER_ONLY
2260 | MBEDTLS_X509_KU_DECIPHER_ONLY;
2261
2262 if( ( crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE ) == 0 )
2263 return( 0 );
2264
2265 usage_must = usage & ~may_mask;
2266
2267 if( ( ( crt->key_usage & ~may_mask ) & usage_must ) != usage_must )
2268 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
2269
2270 usage_may = usage & may_mask;
2271
2272 if( ( ( crt->key_usage & may_mask ) | usage_may ) != usage_may )
2273 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
2274
2275 return( 0 );
2276 }
2277
mbedtls_x509_crt_check_extended_key_usage(const mbedtls_x509_crt * crt,const char * usage_oid,size_t usage_len)2278 int mbedtls_x509_crt_check_extended_key_usage( const mbedtls_x509_crt *crt,
2279 const char *usage_oid,
2280 size_t usage_len )
2281 {
2282 const mbedtls_x509_sequence *cur;
2283
2284 /* Extension is not mandatory, absent means no restriction */
2285 if( ( crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE ) == 0 )
2286 return( 0 );
2287
2288 /*
2289 * Look for the requested usage (or wildcard ANY) in our list
2290 */
2291 for( cur = &crt->ext_key_usage; cur != NULL; cur = cur->next )
2292 {
2293 const mbedtls_x509_buf *cur_oid = &cur->buf;
2294
2295 if( cur_oid->len == usage_len &&
2296 memcmp( cur_oid->p, usage_oid, usage_len ) == 0 )
2297 {
2298 return( 0 );
2299 }
2300
2301 if( MBEDTLS_OID_CMP( MBEDTLS_OID_ANY_EXTENDED_KEY_USAGE, cur_oid ) == 0 )
2302 return( 0 );
2303 }
2304
2305 return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
2306 }
2307
2308 #if defined(MBEDTLS_X509_CRL_PARSE_C)
2309 /*
2310 * Return 1 if the certificate is revoked, or 0 otherwise.
2311 */
mbedtls_x509_crt_is_revoked(const mbedtls_x509_crt * crt,const mbedtls_x509_crl * crl)2312 int mbedtls_x509_crt_is_revoked( const mbedtls_x509_crt *crt, const mbedtls_x509_crl *crl )
2313 {
2314 const mbedtls_x509_crl_entry *cur = &crl->entry;
2315
2316 while( cur != NULL && cur->serial.len != 0 )
2317 {
2318 if( crt->serial.len == cur->serial.len &&
2319 memcmp( crt->serial.p, cur->serial.p, crt->serial.len ) == 0 )
2320 {
2321 return( 1 );
2322 }
2323
2324 cur = cur->next;
2325 }
2326
2327 return( 0 );
2328 }
2329
2330 /*
2331 * Check that the given certificate is not revoked according to the CRL.
2332 * Skip validation if no CRL for the given CA is present.
2333 */
x509_crt_verifycrl(mbedtls_x509_crt * crt,mbedtls_x509_crt * ca,mbedtls_x509_crl * crl_list,const mbedtls_x509_crt_profile * profile)2334 static int x509_crt_verifycrl( mbedtls_x509_crt *crt, mbedtls_x509_crt *ca,
2335 mbedtls_x509_crl *crl_list,
2336 const mbedtls_x509_crt_profile *profile )
2337 {
2338 int flags = 0;
2339 unsigned char hash[MBEDTLS_MD_MAX_SIZE];
2340 const mbedtls_md_info_t *md_info;
2341
2342 if( ca == NULL )
2343 return( flags );
2344
2345 while( crl_list != NULL )
2346 {
2347 if( crl_list->version == 0 ||
2348 x509_name_cmp( &crl_list->issuer, &ca->subject ) != 0 )
2349 {
2350 crl_list = crl_list->next;
2351 continue;
2352 }
2353
2354 /*
2355 * Check if the CA is configured to sign CRLs
2356 */
2357 if( mbedtls_x509_crt_check_key_usage( ca,
2358 MBEDTLS_X509_KU_CRL_SIGN ) != 0 )
2359 {
2360 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
2361 break;
2362 }
2363
2364 /*
2365 * Check if CRL is correctly signed by the trusted CA
2366 */
2367 if( x509_profile_check_md_alg( profile, crl_list->sig_md ) != 0 )
2368 flags |= MBEDTLS_X509_BADCRL_BAD_MD;
2369
2370 if( x509_profile_check_pk_alg( profile, crl_list->sig_pk ) != 0 )
2371 flags |= MBEDTLS_X509_BADCRL_BAD_PK;
2372
2373 md_info = mbedtls_md_info_from_type( crl_list->sig_md );
2374 if( mbedtls_md( md_info, crl_list->tbs.p, crl_list->tbs.len, hash ) != 0 )
2375 {
2376 /* Note: this can't happen except after an internal error */
2377 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
2378 break;
2379 }
2380
2381 if( x509_profile_check_key( profile, &ca->pk ) != 0 )
2382 flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
2383
2384 if( mbedtls_pk_verify_ext( crl_list->sig_pk, crl_list->sig_opts, &ca->pk,
2385 crl_list->sig_md, hash, mbedtls_md_get_size( md_info ),
2386 crl_list->sig.p, crl_list->sig.len ) != 0 )
2387 {
2388 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
2389 break;
2390 }
2391
2392 /*
2393 * Check for validity of CRL (Do not drop out)
2394 */
2395 if( mbedtls_x509_time_is_past( &crl_list->next_update ) )
2396 flags |= MBEDTLS_X509_BADCRL_EXPIRED;
2397
2398 if( mbedtls_x509_time_is_future( &crl_list->this_update ) )
2399 flags |= MBEDTLS_X509_BADCRL_FUTURE;
2400
2401 /*
2402 * Check if certificate is revoked
2403 */
2404 if( mbedtls_x509_crt_is_revoked( crt, crl_list ) )
2405 {
2406 flags |= MBEDTLS_X509_BADCERT_REVOKED;
2407 break;
2408 }
2409
2410 crl_list = crl_list->next;
2411 }
2412
2413 return( flags );
2414 }
2415 #endif /* MBEDTLS_X509_CRL_PARSE_C */
2416
2417 /*
2418 * Check the signature of a certificate by its parent
2419 */
x509_crt_check_signature(const mbedtls_x509_crt * child,mbedtls_x509_crt * parent,mbedtls_x509_crt_restart_ctx * rs_ctx)2420 static int x509_crt_check_signature( const mbedtls_x509_crt *child,
2421 mbedtls_x509_crt *parent,
2422 mbedtls_x509_crt_restart_ctx *rs_ctx )
2423 {
2424 unsigned char hash[MBEDTLS_MD_MAX_SIZE];
2425 size_t hash_len;
2426 #if !defined(MBEDTLS_USE_PSA_CRYPTO)
2427 const mbedtls_md_info_t *md_info;
2428 md_info = mbedtls_md_info_from_type( child->sig_md );
2429 hash_len = mbedtls_md_get_size( md_info );
2430
2431 /* Note: hash errors can happen only after an internal error */
2432 if( mbedtls_md( md_info, child->tbs.p, child->tbs.len, hash ) != 0 )
2433 return( -1 );
2434 #else
2435 psa_hash_operation_t hash_operation = PSA_HASH_OPERATION_INIT;
2436 psa_algorithm_t hash_alg = mbedtls_psa_translate_md( child->sig_md );
2437
2438 if( psa_hash_setup( &hash_operation, hash_alg ) != PSA_SUCCESS )
2439 return( -1 );
2440
2441 if( psa_hash_update( &hash_operation, child->tbs.p, child->tbs.len )
2442 != PSA_SUCCESS )
2443 {
2444 return( -1 );
2445 }
2446
2447 if( psa_hash_finish( &hash_operation, hash, sizeof( hash ), &hash_len )
2448 != PSA_SUCCESS )
2449 {
2450 return( -1 );
2451 }
2452 #endif /* MBEDTLS_USE_PSA_CRYPTO */
2453 /* Skip expensive computation on obvious mismatch */
2454 if( ! mbedtls_pk_can_do( &parent->pk, child->sig_pk ) )
2455 return( -1 );
2456
2457 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2458 if( rs_ctx != NULL && child->sig_pk == MBEDTLS_PK_ECDSA )
2459 {
2460 return( mbedtls_pk_verify_restartable( &parent->pk,
2461 child->sig_md, hash, hash_len,
2462 child->sig.p, child->sig.len, &rs_ctx->pk ) );
2463 }
2464 #else
2465 (void) rs_ctx;
2466 #endif
2467
2468 return( mbedtls_pk_verify_ext( child->sig_pk, child->sig_opts, &parent->pk,
2469 child->sig_md, hash, hash_len,
2470 child->sig.p, child->sig.len ) );
2471 }
2472
2473 /*
2474 * Check if 'parent' is a suitable parent (signing CA) for 'child'.
2475 * Return 0 if yes, -1 if not.
2476 *
2477 * top means parent is a locally-trusted certificate
2478 */
x509_crt_check_parent(const mbedtls_x509_crt * child,const mbedtls_x509_crt * parent,int top)2479 static int x509_crt_check_parent( const mbedtls_x509_crt *child,
2480 const mbedtls_x509_crt *parent,
2481 int top )
2482 {
2483 int need_ca_bit;
2484
2485 /* Parent must be the issuer */
2486 if( x509_name_cmp( &child->issuer, &parent->subject ) != 0 )
2487 return( -1 );
2488
2489 /* Parent must have the basicConstraints CA bit set as a general rule */
2490 need_ca_bit = 1;
2491
2492 /* Exception: v1/v2 certificates that are locally trusted. */
2493 if( top && parent->version < 3 )
2494 need_ca_bit = 0;
2495
2496 if( need_ca_bit && ! parent->ca_istrue )
2497 return( -1 );
2498
2499 if( need_ca_bit &&
2500 mbedtls_x509_crt_check_key_usage( parent, MBEDTLS_X509_KU_KEY_CERT_SIGN ) != 0 )
2501 {
2502 return( -1 );
2503 }
2504
2505 return( 0 );
2506 }
2507
2508 /*
2509 * Find a suitable parent for child in candidates, or return NULL.
2510 *
2511 * Here suitable is defined as:
2512 * 1. subject name matches child's issuer
2513 * 2. if necessary, the CA bit is set and key usage allows signing certs
2514 * 3. for trusted roots, the signature is correct
2515 * (for intermediates, the signature is checked and the result reported)
2516 * 4. pathlen constraints are satisfied
2517 *
2518 * If there's a suitable candidate which is also time-valid, return the first
2519 * such. Otherwise, return the first suitable candidate (or NULL if there is
2520 * none).
2521 *
2522 * The rationale for this rule is that someone could have a list of trusted
2523 * roots with two versions on the same root with different validity periods.
2524 * (At least one user reported having such a list and wanted it to just work.)
2525 * The reason we don't just require time-validity is that generally there is
2526 * only one version, and if it's expired we want the flags to state that
2527 * rather than NOT_TRUSTED, as would be the case if we required it here.
2528 *
2529 * The rationale for rule 3 (signature for trusted roots) is that users might
2530 * have two versions of the same CA with different keys in their list, and the
2531 * way we select the correct one is by checking the signature (as we don't
2532 * rely on key identifier extensions). (This is one way users might choose to
2533 * handle key rollover, another relies on self-issued certs, see [SIRO].)
2534 *
2535 * Arguments:
2536 * - [in] child: certificate for which we're looking for a parent
2537 * - [in] candidates: chained list of potential parents
2538 * - [out] r_parent: parent found (or NULL)
2539 * - [out] r_signature_is_good: 1 if child signature by parent is valid, or 0
2540 * - [in] top: 1 if candidates consists of trusted roots, ie we're at the top
2541 * of the chain, 0 otherwise
2542 * - [in] path_cnt: number of intermediates seen so far
2543 * - [in] self_cnt: number of self-signed intermediates seen so far
2544 * (will never be greater than path_cnt)
2545 * - [in-out] rs_ctx: context for restarting operations
2546 *
2547 * Return value:
2548 * - 0 on success
2549 * - MBEDTLS_ERR_ECP_IN_PROGRESS otherwise
2550 */
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)2551 static int x509_crt_find_parent_in(
2552 mbedtls_x509_crt *child,
2553 mbedtls_x509_crt *candidates,
2554 mbedtls_x509_crt **r_parent,
2555 int *r_signature_is_good,
2556 int top,
2557 unsigned path_cnt,
2558 unsigned self_cnt,
2559 mbedtls_x509_crt_restart_ctx *rs_ctx )
2560 {
2561 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
2562 mbedtls_x509_crt *parent, *fallback_parent;
2563 int signature_is_good = 0, fallback_signature_is_good;
2564
2565 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2566 /* did we have something in progress? */
2567 if( rs_ctx != NULL && rs_ctx->parent != NULL )
2568 {
2569 /* restore saved state */
2570 parent = rs_ctx->parent;
2571 fallback_parent = rs_ctx->fallback_parent;
2572 fallback_signature_is_good = rs_ctx->fallback_signature_is_good;
2573
2574 /* clear saved state */
2575 rs_ctx->parent = NULL;
2576 rs_ctx->fallback_parent = NULL;
2577 rs_ctx->fallback_signature_is_good = 0;
2578
2579 /* resume where we left */
2580 goto check_signature;
2581 }
2582 #endif
2583
2584 fallback_parent = NULL;
2585 fallback_signature_is_good = 0;
2586
2587 for( parent = candidates; parent != NULL; parent = parent->next )
2588 {
2589 /* basic parenting skills (name, CA bit, key usage) */
2590 if( x509_crt_check_parent( child, parent, top ) != 0 )
2591 continue;
2592
2593 /* +1 because stored max_pathlen is 1 higher that the actual value */
2594 if( parent->max_pathlen > 0 &&
2595 (size_t) parent->max_pathlen < 1 + path_cnt - self_cnt )
2596 {
2597 continue;
2598 }
2599
2600 /* Signature */
2601 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2602 check_signature:
2603 #endif
2604 ret = x509_crt_check_signature( child, parent, rs_ctx );
2605
2606 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2607 if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
2608 {
2609 /* save state */
2610 rs_ctx->parent = parent;
2611 rs_ctx->fallback_parent = fallback_parent;
2612 rs_ctx->fallback_signature_is_good = fallback_signature_is_good;
2613
2614 return( ret );
2615 }
2616 #else
2617 (void) ret;
2618 #endif
2619
2620 signature_is_good = ret == 0;
2621 if( top && ! signature_is_good )
2622 continue;
2623
2624 /* optional time check */
2625 if( mbedtls_x509_time_is_past( &parent->valid_to ) ||
2626 mbedtls_x509_time_is_future( &parent->valid_from ) )
2627 {
2628 if( fallback_parent == NULL )
2629 {
2630 fallback_parent = parent;
2631 fallback_signature_is_good = signature_is_good;
2632 }
2633
2634 continue;
2635 }
2636
2637 *r_parent = parent;
2638 *r_signature_is_good = signature_is_good;
2639
2640 break;
2641 }
2642
2643 if( parent == NULL )
2644 {
2645 *r_parent = fallback_parent;
2646 *r_signature_is_good = fallback_signature_is_good;
2647 }
2648
2649 return( 0 );
2650 }
2651
2652 /*
2653 * Find a parent in trusted CAs or the provided chain, or return NULL.
2654 *
2655 * Searches in trusted CAs first, and return the first suitable parent found
2656 * (see find_parent_in() for definition of suitable).
2657 *
2658 * Arguments:
2659 * - [in] child: certificate for which we're looking for a parent, followed
2660 * by a chain of possible intermediates
2661 * - [in] trust_ca: list of locally trusted certificates
2662 * - [out] parent: parent found (or NULL)
2663 * - [out] parent_is_trusted: 1 if returned `parent` is trusted, or 0
2664 * - [out] signature_is_good: 1 if child signature by parent is valid, or 0
2665 * - [in] path_cnt: number of links in the chain so far (EE -> ... -> child)
2666 * - [in] self_cnt: number of self-signed certs in the chain so far
2667 * (will always be no greater than path_cnt)
2668 * - [in-out] rs_ctx: context for restarting operations
2669 *
2670 * Return value:
2671 * - 0 on success
2672 * - MBEDTLS_ERR_ECP_IN_PROGRESS otherwise
2673 */
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)2674 static int x509_crt_find_parent(
2675 mbedtls_x509_crt *child,
2676 mbedtls_x509_crt *trust_ca,
2677 mbedtls_x509_crt **parent,
2678 int *parent_is_trusted,
2679 int *signature_is_good,
2680 unsigned path_cnt,
2681 unsigned self_cnt,
2682 mbedtls_x509_crt_restart_ctx *rs_ctx )
2683 {
2684 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
2685 mbedtls_x509_crt *search_list;
2686
2687 *parent_is_trusted = 1;
2688
2689 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2690 /* restore then clear saved state if we have some stored */
2691 if( rs_ctx != NULL && rs_ctx->parent_is_trusted != -1 )
2692 {
2693 *parent_is_trusted = rs_ctx->parent_is_trusted;
2694 rs_ctx->parent_is_trusted = -1;
2695 }
2696 #endif
2697
2698 while( 1 ) {
2699 search_list = *parent_is_trusted ? trust_ca : child->next;
2700
2701 ret = x509_crt_find_parent_in( child, search_list,
2702 parent, signature_is_good,
2703 *parent_is_trusted,
2704 path_cnt, self_cnt, rs_ctx );
2705
2706 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2707 if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
2708 {
2709 /* save state */
2710 rs_ctx->parent_is_trusted = *parent_is_trusted;
2711 return( ret );
2712 }
2713 #else
2714 (void) ret;
2715 #endif
2716
2717 /* stop here if found or already in second iteration */
2718 if( *parent != NULL || *parent_is_trusted == 0 )
2719 break;
2720
2721 /* prepare second iteration */
2722 *parent_is_trusted = 0;
2723 }
2724
2725 /* extra precaution against mistakes in the caller */
2726 if( *parent == NULL )
2727 {
2728 *parent_is_trusted = 0;
2729 *signature_is_good = 0;
2730 }
2731
2732 return( 0 );
2733 }
2734
2735 /*
2736 * Check if an end-entity certificate is locally trusted
2737 *
2738 * Currently we require such certificates to be self-signed (actually only
2739 * check for self-issued as self-signatures are not checked)
2740 */
x509_crt_check_ee_locally_trusted(mbedtls_x509_crt * crt,mbedtls_x509_crt * trust_ca)2741 static int x509_crt_check_ee_locally_trusted(
2742 mbedtls_x509_crt *crt,
2743 mbedtls_x509_crt *trust_ca )
2744 {
2745 mbedtls_x509_crt *cur;
2746
2747 /* must be self-issued */
2748 if( x509_name_cmp( &crt->issuer, &crt->subject ) != 0 )
2749 return( -1 );
2750
2751 /* look for an exact match with trusted cert */
2752 for( cur = trust_ca; cur != NULL; cur = cur->next )
2753 {
2754 if( crt->raw.len == cur->raw.len &&
2755 memcmp( crt->raw.p, cur->raw.p, crt->raw.len ) == 0 )
2756 {
2757 return( 0 );
2758 }
2759 }
2760
2761 /* too bad */
2762 return( -1 );
2763 }
2764
2765 /*
2766 * Build and verify a certificate chain
2767 *
2768 * Given a peer-provided list of certificates EE, C1, ..., Cn and
2769 * a list of trusted certs R1, ... Rp, try to build and verify a chain
2770 * EE, Ci1, ... Ciq [, Rj]
2771 * such that every cert in the chain is a child of the next one,
2772 * jumping to a trusted root as early as possible.
2773 *
2774 * Verify that chain and return it with flags for all issues found.
2775 *
2776 * Special cases:
2777 * - EE == Rj -> return a one-element list containing it
2778 * - EE, Ci1, ..., Ciq cannot be continued with a trusted root
2779 * -> return that chain with NOT_TRUSTED set on Ciq
2780 *
2781 * Tests for (aspects of) this function should include at least:
2782 * - trusted EE
2783 * - EE -> trusted root
2784 * - EE -> intermediate CA -> trusted root
2785 * - if relevant: EE untrusted
2786 * - if relevant: EE -> intermediate, untrusted
2787 * with the aspect under test checked at each relevant level (EE, int, root).
2788 * For some aspects longer chains are required, but usually length 2 is
2789 * enough (but length 1 is not in general).
2790 *
2791 * Arguments:
2792 * - [in] crt: the cert list EE, C1, ..., Cn
2793 * - [in] trust_ca: the trusted list R1, ..., Rp
2794 * - [in] ca_crl, profile: as in verify_with_profile()
2795 * - [out] ver_chain: the built and verified chain
2796 * Only valid when return value is 0, may contain garbage otherwise!
2797 * Restart note: need not be the same when calling again to resume.
2798 * - [in-out] rs_ctx: context for restarting operations
2799 *
2800 * Return value:
2801 * - non-zero if the chain could not be fully built and examined
2802 * - 0 is the chain was successfully built and examined,
2803 * even if it was found to be invalid
2804 */
x509_crt_verify_chain(mbedtls_x509_crt * crt,mbedtls_x509_crt * trust_ca,mbedtls_x509_crl * ca_crl,mbedtls_x509_crt_ca_cb_t f_ca_cb,void * p_ca_cb,const mbedtls_x509_crt_profile * profile,mbedtls_x509_crt_verify_chain * ver_chain,mbedtls_x509_crt_restart_ctx * rs_ctx)2805 static int x509_crt_verify_chain(
2806 mbedtls_x509_crt *crt,
2807 mbedtls_x509_crt *trust_ca,
2808 mbedtls_x509_crl *ca_crl,
2809 mbedtls_x509_crt_ca_cb_t f_ca_cb,
2810 void *p_ca_cb,
2811 const mbedtls_x509_crt_profile *profile,
2812 mbedtls_x509_crt_verify_chain *ver_chain,
2813 mbedtls_x509_crt_restart_ctx *rs_ctx )
2814 {
2815 /* Don't initialize any of those variables here, so that the compiler can
2816 * catch potential issues with jumping ahead when restarting */
2817 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
2818 uint32_t *flags;
2819 mbedtls_x509_crt_verify_chain_item *cur;
2820 mbedtls_x509_crt *child;
2821 mbedtls_x509_crt *parent;
2822 int parent_is_trusted;
2823 int child_is_trusted;
2824 int signature_is_good;
2825 unsigned self_cnt;
2826 mbedtls_x509_crt *cur_trust_ca = NULL;
2827
2828 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2829 /* resume if we had an operation in progress */
2830 if( rs_ctx != NULL && rs_ctx->in_progress == x509_crt_rs_find_parent )
2831 {
2832 /* restore saved state */
2833 *ver_chain = rs_ctx->ver_chain; /* struct copy */
2834 self_cnt = rs_ctx->self_cnt;
2835
2836 /* restore derived state */
2837 cur = &ver_chain->items[ver_chain->len - 1];
2838 child = cur->crt;
2839 flags = &cur->flags;
2840
2841 goto find_parent;
2842 }
2843 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
2844
2845 child = crt;
2846 self_cnt = 0;
2847 parent_is_trusted = 0;
2848 child_is_trusted = 0;
2849
2850 while( 1 ) {
2851 /* Add certificate to the verification chain */
2852 cur = &ver_chain->items[ver_chain->len];
2853 cur->crt = child;
2854 cur->flags = 0;
2855 ver_chain->len++;
2856 flags = &cur->flags;
2857
2858 /* Check time-validity (all certificates) */
2859 if( mbedtls_x509_time_is_past( &child->valid_to ) )
2860 *flags |= MBEDTLS_X509_BADCERT_EXPIRED;
2861
2862 if( mbedtls_x509_time_is_future( &child->valid_from ) )
2863 *flags |= MBEDTLS_X509_BADCERT_FUTURE;
2864
2865 /* Stop here for trusted roots (but not for trusted EE certs) */
2866 if( child_is_trusted )
2867 return( 0 );
2868
2869 /* Check signature algorithm: MD & PK algs */
2870 if( x509_profile_check_md_alg( profile, child->sig_md ) != 0 )
2871 *flags |= MBEDTLS_X509_BADCERT_BAD_MD;
2872
2873 if( x509_profile_check_pk_alg( profile, child->sig_pk ) != 0 )
2874 *flags |= MBEDTLS_X509_BADCERT_BAD_PK;
2875
2876 /* Special case: EE certs that are locally trusted */
2877 if( ver_chain->len == 1 &&
2878 x509_crt_check_ee_locally_trusted( child, trust_ca ) == 0 )
2879 {
2880 return( 0 );
2881 }
2882
2883 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2884 find_parent:
2885 #endif
2886
2887 /* Obtain list of potential trusted signers from CA callback,
2888 * or use statically provided list. */
2889 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
2890 if( f_ca_cb != NULL )
2891 {
2892 mbedtls_x509_crt_free( ver_chain->trust_ca_cb_result );
2893 mbedtls_free( ver_chain->trust_ca_cb_result );
2894 ver_chain->trust_ca_cb_result = NULL;
2895
2896 ret = f_ca_cb( p_ca_cb, child, &ver_chain->trust_ca_cb_result );
2897 if( ret != 0 )
2898 return( MBEDTLS_ERR_X509_FATAL_ERROR );
2899
2900 cur_trust_ca = ver_chain->trust_ca_cb_result;
2901 }
2902 else
2903 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
2904 {
2905 ((void) f_ca_cb);
2906 ((void) p_ca_cb);
2907 cur_trust_ca = trust_ca;
2908 }
2909
2910 /* Look for a parent in trusted CAs or up the chain */
2911 ret = x509_crt_find_parent( child, cur_trust_ca, &parent,
2912 &parent_is_trusted, &signature_is_good,
2913 ver_chain->len - 1, self_cnt, rs_ctx );
2914
2915 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2916 if( rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS )
2917 {
2918 /* save state */
2919 rs_ctx->in_progress = x509_crt_rs_find_parent;
2920 rs_ctx->self_cnt = self_cnt;
2921 rs_ctx->ver_chain = *ver_chain; /* struct copy */
2922
2923 return( ret );
2924 }
2925 #else
2926 (void) ret;
2927 #endif
2928
2929 /* No parent? We're done here */
2930 if( parent == NULL )
2931 {
2932 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
2933 return( 0 );
2934 }
2935
2936 /* Count intermediate self-issued (not necessarily self-signed) certs.
2937 * These can occur with some strategies for key rollover, see [SIRO],
2938 * and should be excluded from max_pathlen checks. */
2939 if( ver_chain->len != 1 &&
2940 x509_name_cmp( &child->issuer, &child->subject ) == 0 )
2941 {
2942 self_cnt++;
2943 }
2944
2945 /* path_cnt is 0 for the first intermediate CA,
2946 * and if parent is trusted it's not an intermediate CA */
2947 if( ! parent_is_trusted &&
2948 ver_chain->len > MBEDTLS_X509_MAX_INTERMEDIATE_CA )
2949 {
2950 /* return immediately to avoid overflow the chain array */
2951 return( MBEDTLS_ERR_X509_FATAL_ERROR );
2952 }
2953
2954 /* signature was checked while searching parent */
2955 if( ! signature_is_good )
2956 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
2957
2958 /* check size of signing key */
2959 if( x509_profile_check_key( profile, &parent->pk ) != 0 )
2960 *flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
2961
2962 #if defined(MBEDTLS_X509_CRL_PARSE_C)
2963 /* Check trusted CA's CRL for the given crt */
2964 *flags |= x509_crt_verifycrl( child, parent, ca_crl, profile );
2965 #else
2966 (void) ca_crl;
2967 #endif
2968
2969 /* prepare for next iteration */
2970 child = parent;
2971 parent = NULL;
2972 child_is_trusted = parent_is_trusted;
2973 signature_is_good = 0;
2974 }
2975 }
2976
2977 /*
2978 * Check for CN match
2979 */
x509_crt_check_cn(const mbedtls_x509_buf * name,const char * cn,size_t cn_len)2980 static int x509_crt_check_cn( const mbedtls_x509_buf *name,
2981 const char *cn, size_t cn_len )
2982 {
2983 /* try exact match */
2984 if( name->len == cn_len &&
2985 x509_memcasecmp( cn, name->p, cn_len ) == 0 )
2986 {
2987 return( 0 );
2988 }
2989
2990 /* try wildcard match */
2991 if( x509_check_wildcard( cn, name ) == 0 )
2992 {
2993 return( 0 );
2994 }
2995
2996 return( -1 );
2997 }
2998
2999 /*
3000 * Check for SAN match, see RFC 5280 Section 4.2.1.6
3001 */
x509_crt_check_san(const mbedtls_x509_buf * name,const char * cn,size_t cn_len)3002 static int x509_crt_check_san( const mbedtls_x509_buf *name,
3003 const char *cn, size_t cn_len )
3004 {
3005 const unsigned char san_type = (unsigned char) name->tag &
3006 MBEDTLS_ASN1_TAG_VALUE_MASK;
3007
3008 /* dNSName */
3009 if( san_type == MBEDTLS_X509_SAN_DNS_NAME )
3010 return( x509_crt_check_cn( name, cn, cn_len ) );
3011
3012 /* (We may handle other types here later.) */
3013
3014 /* Unrecognized type */
3015 return( -1 );
3016 }
3017
3018 /*
3019 * Verify the requested CN - only call this if cn is not NULL!
3020 */
x509_crt_verify_name(const mbedtls_x509_crt * crt,const char * cn,uint32_t * flags)3021 static void x509_crt_verify_name( const mbedtls_x509_crt *crt,
3022 const char *cn,
3023 uint32_t *flags )
3024 {
3025 const mbedtls_x509_name *name;
3026 const mbedtls_x509_sequence *cur;
3027 size_t cn_len = strlen( cn );
3028
3029 if( crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME )
3030 {
3031 for( cur = &crt->subject_alt_names; cur != NULL; cur = cur->next )
3032 {
3033 if( x509_crt_check_san( &cur->buf, cn, cn_len ) == 0 )
3034 break;
3035 }
3036
3037 if( cur == NULL )
3038 *flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH;
3039 }
3040 else
3041 {
3042 for( name = &crt->subject; name != NULL; name = name->next )
3043 {
3044 if( MBEDTLS_OID_CMP( MBEDTLS_OID_AT_CN, &name->oid ) == 0 &&
3045 x509_crt_check_cn( &name->val, cn, cn_len ) == 0 )
3046 {
3047 break;
3048 }
3049 }
3050
3051 if( name == NULL )
3052 *flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH;
3053 }
3054 }
3055
3056 /*
3057 * Merge the flags for all certs in the chain, after calling callback
3058 */
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)3059 static int x509_crt_merge_flags_with_cb(
3060 uint32_t *flags,
3061 const mbedtls_x509_crt_verify_chain *ver_chain,
3062 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3063 void *p_vrfy )
3064 {
3065 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
3066 unsigned i;
3067 uint32_t cur_flags;
3068 const mbedtls_x509_crt_verify_chain_item *cur;
3069
3070 for( i = ver_chain->len; i != 0; --i )
3071 {
3072 cur = &ver_chain->items[i-1];
3073 cur_flags = cur->flags;
3074
3075 if( NULL != f_vrfy )
3076 if( ( ret = f_vrfy( p_vrfy, cur->crt, (int) i-1, &cur_flags ) ) != 0 )
3077 return( ret );
3078
3079 *flags |= cur_flags;
3080 }
3081
3082 return( 0 );
3083 }
3084
3085 /*
3086 * Verify the certificate validity, with profile, restartable version
3087 *
3088 * This function:
3089 * - checks the requested CN (if any)
3090 * - checks the type and size of the EE cert's key,
3091 * as that isn't done as part of chain building/verification currently
3092 * - builds and verifies the chain
3093 * - then calls the callback and merges the flags
3094 *
3095 * The parameters pairs `trust_ca`, `ca_crl` and `f_ca_cb`, `p_ca_cb`
3096 * are mutually exclusive: If `f_ca_cb != NULL`, it will be used by the
3097 * verification routine to search for trusted signers, and CRLs will
3098 * be disabled. Otherwise, `trust_ca` will be used as the static list
3099 * of trusted signers, and `ca_crl` will be use as the static list
3100 * of CRLs.
3101 */
x509_crt_verify_restartable_ca_cb(mbedtls_x509_crt * crt,mbedtls_x509_crt * trust_ca,mbedtls_x509_crl * ca_crl,mbedtls_x509_crt_ca_cb_t f_ca_cb,void * p_ca_cb,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)3102 static int x509_crt_verify_restartable_ca_cb( mbedtls_x509_crt *crt,
3103 mbedtls_x509_crt *trust_ca,
3104 mbedtls_x509_crl *ca_crl,
3105 mbedtls_x509_crt_ca_cb_t f_ca_cb,
3106 void *p_ca_cb,
3107 const mbedtls_x509_crt_profile *profile,
3108 const char *cn, uint32_t *flags,
3109 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3110 void *p_vrfy,
3111 mbedtls_x509_crt_restart_ctx *rs_ctx )
3112 {
3113 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
3114 mbedtls_pk_type_t pk_type;
3115 mbedtls_x509_crt_verify_chain ver_chain;
3116 uint32_t ee_flags;
3117
3118 *flags = 0;
3119 ee_flags = 0;
3120 x509_crt_verify_chain_reset( &ver_chain );
3121
3122 if( profile == NULL )
3123 {
3124 ret = MBEDTLS_ERR_X509_BAD_INPUT_DATA;
3125 goto exit;
3126 }
3127
3128 /* check name if requested */
3129 if( cn != NULL )
3130 x509_crt_verify_name( crt, cn, &ee_flags );
3131
3132 /* Check the type and size of the key */
3133 pk_type = mbedtls_pk_get_type( &crt->pk );
3134
3135 if( x509_profile_check_pk_alg( profile, pk_type ) != 0 )
3136 ee_flags |= MBEDTLS_X509_BADCERT_BAD_PK;
3137
3138 if( x509_profile_check_key( profile, &crt->pk ) != 0 )
3139 ee_flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
3140
3141 /* Check the chain */
3142 ret = x509_crt_verify_chain( crt, trust_ca, ca_crl,
3143 f_ca_cb, p_ca_cb, profile,
3144 &ver_chain, rs_ctx );
3145
3146 if( ret != 0 )
3147 goto exit;
3148
3149 /* Merge end-entity flags */
3150 ver_chain.items[0].flags |= ee_flags;
3151
3152 /* Build final flags, calling callback on the way if any */
3153 ret = x509_crt_merge_flags_with_cb( flags, &ver_chain, f_vrfy, p_vrfy );
3154
3155 exit:
3156
3157 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
3158 mbedtls_x509_crt_free( ver_chain.trust_ca_cb_result );
3159 mbedtls_free( ver_chain.trust_ca_cb_result );
3160 ver_chain.trust_ca_cb_result = NULL;
3161 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
3162
3163 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
3164 if( rs_ctx != NULL && ret != MBEDTLS_ERR_ECP_IN_PROGRESS )
3165 mbedtls_x509_crt_restart_free( rs_ctx );
3166 #endif
3167
3168 /* prevent misuse of the vrfy callback - VERIFY_FAILED would be ignored by
3169 * the SSL module for authmode optional, but non-zero return from the
3170 * callback means a fatal error so it shouldn't be ignored */
3171 if( ret == MBEDTLS_ERR_X509_CERT_VERIFY_FAILED )
3172 ret = MBEDTLS_ERR_X509_FATAL_ERROR;
3173
3174 if( ret != 0 )
3175 {
3176 *flags = (uint32_t) -1;
3177 return( ret );
3178 }
3179
3180 if( *flags != 0 )
3181 return( MBEDTLS_ERR_X509_CERT_VERIFY_FAILED );
3182
3183 return( 0 );
3184 }
3185
3186
3187 /*
3188 * Verify the certificate validity (default profile, not restartable)
3189 */
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)3190 int mbedtls_x509_crt_verify( mbedtls_x509_crt *crt,
3191 mbedtls_x509_crt *trust_ca,
3192 mbedtls_x509_crl *ca_crl,
3193 const char *cn, uint32_t *flags,
3194 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3195 void *p_vrfy )
3196 {
3197 return( x509_crt_verify_restartable_ca_cb( crt, trust_ca, ca_crl,
3198 NULL, NULL,
3199 &mbedtls_x509_crt_profile_default,
3200 cn, flags,
3201 f_vrfy, p_vrfy, NULL ) );
3202 }
3203
3204 /*
3205 * Verify the certificate validity (user-chosen profile, not restartable)
3206 */
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)3207 int mbedtls_x509_crt_verify_with_profile( mbedtls_x509_crt *crt,
3208 mbedtls_x509_crt *trust_ca,
3209 mbedtls_x509_crl *ca_crl,
3210 const mbedtls_x509_crt_profile *profile,
3211 const char *cn, uint32_t *flags,
3212 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3213 void *p_vrfy )
3214 {
3215 return( x509_crt_verify_restartable_ca_cb( crt, trust_ca, ca_crl,
3216 NULL, NULL,
3217 profile, cn, flags,
3218 f_vrfy, p_vrfy, NULL ) );
3219 }
3220
3221 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
3222 /*
3223 * Verify the certificate validity (user-chosen profile, CA callback,
3224 * not restartable).
3225 */
mbedtls_x509_crt_verify_with_ca_cb(mbedtls_x509_crt * crt,mbedtls_x509_crt_ca_cb_t f_ca_cb,void * p_ca_cb,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)3226 int mbedtls_x509_crt_verify_with_ca_cb( mbedtls_x509_crt *crt,
3227 mbedtls_x509_crt_ca_cb_t f_ca_cb,
3228 void *p_ca_cb,
3229 const mbedtls_x509_crt_profile *profile,
3230 const char *cn, uint32_t *flags,
3231 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3232 void *p_vrfy )
3233 {
3234 return( x509_crt_verify_restartable_ca_cb( crt, NULL, NULL,
3235 f_ca_cb, p_ca_cb,
3236 profile, cn, flags,
3237 f_vrfy, p_vrfy, NULL ) );
3238 }
3239 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
3240
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)3241 int mbedtls_x509_crt_verify_restartable( mbedtls_x509_crt *crt,
3242 mbedtls_x509_crt *trust_ca,
3243 mbedtls_x509_crl *ca_crl,
3244 const mbedtls_x509_crt_profile *profile,
3245 const char *cn, uint32_t *flags,
3246 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3247 void *p_vrfy,
3248 mbedtls_x509_crt_restart_ctx *rs_ctx )
3249 {
3250 return( x509_crt_verify_restartable_ca_cb( crt, trust_ca, ca_crl,
3251 NULL, NULL,
3252 profile, cn, flags,
3253 f_vrfy, p_vrfy, rs_ctx ) );
3254 }
3255
3256
3257 /*
3258 * Initialize a certificate chain
3259 */
mbedtls_x509_crt_init(mbedtls_x509_crt * crt)3260 void mbedtls_x509_crt_init( mbedtls_x509_crt *crt )
3261 {
3262 memset( crt, 0, sizeof(mbedtls_x509_crt) );
3263 }
3264
3265 /*
3266 * Unallocate all certificate data
3267 */
mbedtls_x509_crt_free(mbedtls_x509_crt * crt)3268 void mbedtls_x509_crt_free( mbedtls_x509_crt *crt )
3269 {
3270 mbedtls_x509_crt *cert_cur = crt;
3271 mbedtls_x509_crt *cert_prv;
3272 mbedtls_x509_name *name_cur;
3273 mbedtls_x509_name *name_prv;
3274 mbedtls_x509_sequence *seq_cur;
3275 mbedtls_x509_sequence *seq_prv;
3276
3277 if( crt == NULL )
3278 return;
3279
3280 do
3281 {
3282 mbedtls_pk_free( &cert_cur->pk );
3283
3284 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
3285 mbedtls_free( cert_cur->sig_opts );
3286 #endif
3287
3288 name_cur = cert_cur->issuer.next;
3289 while( name_cur != NULL )
3290 {
3291 name_prv = name_cur;
3292 name_cur = name_cur->next;
3293 mbedtls_platform_zeroize( name_prv, sizeof( mbedtls_x509_name ) );
3294 mbedtls_free( name_prv );
3295 }
3296
3297 name_cur = cert_cur->subject.next;
3298 while( name_cur != NULL )
3299 {
3300 name_prv = name_cur;
3301 name_cur = name_cur->next;
3302 mbedtls_platform_zeroize( name_prv, sizeof( mbedtls_x509_name ) );
3303 mbedtls_free( name_prv );
3304 }
3305
3306 seq_cur = cert_cur->ext_key_usage.next;
3307 while( seq_cur != NULL )
3308 {
3309 seq_prv = seq_cur;
3310 seq_cur = seq_cur->next;
3311 mbedtls_platform_zeroize( seq_prv,
3312 sizeof( mbedtls_x509_sequence ) );
3313 mbedtls_free( seq_prv );
3314 }
3315
3316 seq_cur = cert_cur->subject_alt_names.next;
3317 while( seq_cur != NULL )
3318 {
3319 seq_prv = seq_cur;
3320 seq_cur = seq_cur->next;
3321 mbedtls_platform_zeroize( seq_prv,
3322 sizeof( mbedtls_x509_sequence ) );
3323 mbedtls_free( seq_prv );
3324 }
3325
3326 seq_cur = cert_cur->certificate_policies.next;
3327 while( seq_cur != NULL )
3328 {
3329 seq_prv = seq_cur;
3330 seq_cur = seq_cur->next;
3331 mbedtls_platform_zeroize( seq_prv,
3332 sizeof( mbedtls_x509_sequence ) );
3333 mbedtls_free( seq_prv );
3334 }
3335
3336 if( cert_cur->raw.p != NULL && cert_cur->own_buffer )
3337 {
3338 mbedtls_platform_zeroize( cert_cur->raw.p, cert_cur->raw.len );
3339 mbedtls_free( cert_cur->raw.p );
3340 }
3341
3342 cert_cur = cert_cur->next;
3343 }
3344 while( cert_cur != NULL );
3345
3346 cert_cur = crt;
3347 do
3348 {
3349 cert_prv = cert_cur;
3350 cert_cur = cert_cur->next;
3351
3352 mbedtls_platform_zeroize( cert_prv, sizeof( mbedtls_x509_crt ) );
3353 if( cert_prv != crt )
3354 mbedtls_free( cert_prv );
3355 }
3356 while( cert_cur != NULL );
3357 }
3358
3359 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
3360 /*
3361 * Initialize a restart context
3362 */
mbedtls_x509_crt_restart_init(mbedtls_x509_crt_restart_ctx * ctx)3363 void mbedtls_x509_crt_restart_init( mbedtls_x509_crt_restart_ctx *ctx )
3364 {
3365 mbedtls_pk_restart_init( &ctx->pk );
3366
3367 ctx->parent = NULL;
3368 ctx->fallback_parent = NULL;
3369 ctx->fallback_signature_is_good = 0;
3370
3371 ctx->parent_is_trusted = -1;
3372
3373 ctx->in_progress = x509_crt_rs_none;
3374 ctx->self_cnt = 0;
3375 x509_crt_verify_chain_reset( &ctx->ver_chain );
3376 }
3377
3378 /*
3379 * Free the components of a restart context
3380 */
mbedtls_x509_crt_restart_free(mbedtls_x509_crt_restart_ctx * ctx)3381 void mbedtls_x509_crt_restart_free( mbedtls_x509_crt_restart_ctx *ctx )
3382 {
3383 if( ctx == NULL )
3384 return;
3385
3386 mbedtls_pk_restart_free( &ctx->pk );
3387 mbedtls_x509_crt_restart_init( ctx );
3388 }
3389 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
3390
3391 #endif /* MBEDTLS_X509_CRT_PARSE_C */
3392