1 /*
2 * X.509 certificate parsing and verification
3 *
4 * Copyright The Mbed TLS Contributors
5 * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
6 */
7 /*
8 * The ITU-T X.509 standard defines a certificate format for PKI.
9 *
10 * http://www.ietf.org/rfc/rfc5280.txt (Certificates and CRLs)
11 * http://www.ietf.org/rfc/rfc3279.txt (Alg IDs for CRLs)
12 * http://www.ietf.org/rfc/rfc2986.txt (CSRs, aka PKCS#10)
13 *
14 * http://www.itu.int/ITU-T/studygroups/com17/languages/X.680-0207.pdf
15 * http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf
16 *
17 * [SIRO] https://cabforum.org/wp-content/uploads/Chunghwatelecom201503cabforumV4.pdf
18 */
19
20 #include "common.h"
21
22 #if defined(MBEDTLS_X509_CRT_PARSE_C)
23
24 #include "mbedtls/x509_crt.h"
25 #include "mbedtls/error.h"
26 #include "mbedtls/oid.h"
27 #include "mbedtls/platform_util.h"
28
29 #include <string.h>
30
31 #if defined(MBEDTLS_PEM_PARSE_C)
32 #include "mbedtls/pem.h"
33 #endif
34
35 #if defined(MBEDTLS_USE_PSA_CRYPTO)
36 #include "psa/crypto.h"
37 #include "psa_util_internal.h"
38 #include "md_psa.h"
39 #endif /* MBEDTLS_USE_PSA_CRYPTO */
40 #include "pk_internal.h"
41
42 #include "mbedtls/platform.h"
43
44 #if defined(MBEDTLS_THREADING_C)
45 #include "mbedtls/threading.h"
46 #endif
47
48 #if defined(MBEDTLS_HAVE_TIME)
49 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
50 #define WIN32_LEAN_AND_MEAN
51 #include <windows.h>
52 #else
53 #include <time.h>
54 #endif
55 #endif
56
57 #if defined(MBEDTLS_FS_IO)
58 #include <stdio.h>
59 #if !defined(_WIN32) || defined(EFIX64) || defined(EFI32)
60 #include <sys/types.h>
61 #include <sys/stat.h>
62 #if defined(__MBED__)
63 #include <platform/mbed_retarget.h>
64 #else
65 #include <dirent.h>
66 #endif /* __MBED__ */
67 #include <errno.h>
68 #endif /* !_WIN32 || EFIX64 || EFI32 */
69 #endif
70
71 /*
72 * Item in a verification chain: cert and flags for it
73 */
74 typedef struct {
75 mbedtls_x509_crt *crt;
76 uint32_t flags;
77 } x509_crt_verify_chain_item;
78
79 /*
80 * Max size of verification chain: end-entity + intermediates + trusted root
81 */
82 #define X509_MAX_VERIFY_CHAIN_SIZE (MBEDTLS_X509_MAX_INTERMEDIATE_CA + 2)
83
84 /* Default profile. Do not remove items unless there are serious security
85 * concerns. */
86 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_default =
87 {
88 /* Hashes from SHA-256 and above. Note that this selection
89 * should be aligned with ssl_preset_default_hashes in ssl_tls.c. */
90 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA256) |
91 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA384) |
92 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA512),
93 0xFFFFFFF, /* Any PK alg */
94 #if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
95 /* Curves at or above 128-bit security level. Note that this selection
96 * should be aligned with ssl_preset_default_curves in ssl_tls.c. */
97 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP256R1) |
98 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP384R1) |
99 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP521R1) |
100 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_BP256R1) |
101 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_BP384R1) |
102 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_BP512R1) |
103 0,
104 #else /* MBEDTLS_PK_HAVE_ECC_KEYS */
105 0,
106 #endif /* MBEDTLS_PK_HAVE_ECC_KEYS */
107 2048,
108 };
109
110 /* Next-generation profile. Currently identical to the default, but may
111 * be tightened at any time. */
112 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_next =
113 {
114 /* Hashes from SHA-256 and above. */
115 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA256) |
116 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA384) |
117 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA512),
118 0xFFFFFFF, /* Any PK alg */
119 #if defined(MBEDTLS_ECP_C)
120 /* Curves at or above 128-bit security level. */
121 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP256R1) |
122 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP384R1) |
123 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP521R1) |
124 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_BP256R1) |
125 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_BP384R1) |
126 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_BP512R1) |
127 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP256K1),
128 #else
129 0,
130 #endif
131 2048,
132 };
133
134 /*
135 * NSA Suite B Profile
136 */
137 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_suiteb =
138 {
139 /* Only SHA-256 and 384 */
140 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA256) |
141 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA384),
142 /* Only ECDSA */
143 MBEDTLS_X509_ID_FLAG(MBEDTLS_PK_ECDSA) |
144 MBEDTLS_X509_ID_FLAG(MBEDTLS_PK_ECKEY),
145 #if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
146 /* Only NIST P-256 and P-384 */
147 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP256R1) |
148 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP384R1),
149 #else /* MBEDTLS_PK_HAVE_ECC_KEYS */
150 0,
151 #endif /* MBEDTLS_PK_HAVE_ECC_KEYS */
152 0,
153 };
154
155 /*
156 * Empty / all-forbidden profile
157 */
158 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_none =
159 {
160 0,
161 0,
162 0,
163 (uint32_t) -1,
164 };
165
166 /*
167 * Check md_alg against profile
168 * Return 0 if md_alg is acceptable for this profile, -1 otherwise
169 */
x509_profile_check_md_alg(const mbedtls_x509_crt_profile * profile,mbedtls_md_type_t md_alg)170 static int x509_profile_check_md_alg(const mbedtls_x509_crt_profile *profile,
171 mbedtls_md_type_t md_alg)
172 {
173 if (md_alg == MBEDTLS_MD_NONE) {
174 return -1;
175 }
176
177 if ((profile->allowed_mds & MBEDTLS_X509_ID_FLAG(md_alg)) != 0) {
178 return 0;
179 }
180
181 return -1;
182 }
183
184 /*
185 * Check pk_alg against profile
186 * Return 0 if pk_alg is acceptable for this profile, -1 otherwise
187 */
x509_profile_check_pk_alg(const mbedtls_x509_crt_profile * profile,mbedtls_pk_type_t pk_alg)188 static int x509_profile_check_pk_alg(const mbedtls_x509_crt_profile *profile,
189 mbedtls_pk_type_t pk_alg)
190 {
191 if (pk_alg == MBEDTLS_PK_NONE) {
192 return -1;
193 }
194
195 if ((profile->allowed_pks & MBEDTLS_X509_ID_FLAG(pk_alg)) != 0) {
196 return 0;
197 }
198
199 return -1;
200 }
201
202 /*
203 * Check key against profile
204 * Return 0 if pk is acceptable for this profile, -1 otherwise
205 */
x509_profile_check_key(const mbedtls_x509_crt_profile * profile,const mbedtls_pk_context * pk)206 static int x509_profile_check_key(const mbedtls_x509_crt_profile *profile,
207 const mbedtls_pk_context *pk)
208 {
209 const mbedtls_pk_type_t pk_alg = mbedtls_pk_get_type(pk);
210
211 #if defined(MBEDTLS_RSA_C)
212 if (pk_alg == MBEDTLS_PK_RSA || pk_alg == MBEDTLS_PK_RSASSA_PSS) {
213 if (mbedtls_pk_get_bitlen(pk) >= profile->rsa_min_bitlen) {
214 return 0;
215 }
216
217 return -1;
218 }
219 #endif /* MBEDTLS_RSA_C */
220
221 #if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
222 if (pk_alg == MBEDTLS_PK_ECDSA ||
223 pk_alg == MBEDTLS_PK_ECKEY ||
224 pk_alg == MBEDTLS_PK_ECKEY_DH) {
225 const mbedtls_ecp_group_id gid = mbedtls_pk_get_group_id(pk);
226
227 if (gid == MBEDTLS_ECP_DP_NONE) {
228 return -1;
229 }
230
231 if ((profile->allowed_curves & MBEDTLS_X509_ID_FLAG(gid)) != 0) {
232 return 0;
233 }
234
235 return -1;
236 }
237 #endif /* MBEDTLS_PK_HAVE_ECC_KEYS */
238
239 return -1;
240 }
241
242 /*
243 * Like memcmp, but case-insensitive and always returns -1 if different
244 */
x509_memcasecmp(const void * s1,const void * s2,size_t len)245 static int x509_memcasecmp(const void *s1, const void *s2, size_t len)
246 {
247 size_t i;
248 unsigned char diff;
249 const unsigned char *n1 = s1, *n2 = s2;
250
251 for (i = 0; i < len; i++) {
252 diff = n1[i] ^ n2[i];
253
254 if (diff == 0) {
255 continue;
256 }
257
258 if (diff == 32 &&
259 ((n1[i] >= 'a' && n1[i] <= 'z') ||
260 (n1[i] >= 'A' && n1[i] <= 'Z'))) {
261 continue;
262 }
263
264 return -1;
265 }
266
267 return 0;
268 }
269
270 /*
271 * Return 0 if name matches wildcard, -1 otherwise
272 */
x509_check_wildcard(const char * cn,const mbedtls_x509_buf * name)273 static int x509_check_wildcard(const char *cn, const mbedtls_x509_buf *name)
274 {
275 size_t i;
276 size_t cn_idx = 0, cn_len = strlen(cn);
277
278 /* We can't have a match if there is no wildcard to match */
279 if (name->len < 3 || name->p[0] != '*' || name->p[1] != '.') {
280 return -1;
281 }
282
283 for (i = 0; i < cn_len; ++i) {
284 if (cn[i] == '.') {
285 cn_idx = i;
286 break;
287 }
288 }
289
290 if (cn_idx == 0) {
291 return -1;
292 }
293
294 if (cn_len - cn_idx == name->len - 1 &&
295 x509_memcasecmp(name->p + 1, cn + cn_idx, name->len - 1) == 0) {
296 return 0;
297 }
298
299 return -1;
300 }
301
302 /*
303 * Compare two X.509 strings, case-insensitive, and allowing for some encoding
304 * variations (but not all).
305 *
306 * Return 0 if equal, -1 otherwise.
307 */
x509_string_cmp(const mbedtls_x509_buf * a,const mbedtls_x509_buf * b)308 static int x509_string_cmp(const mbedtls_x509_buf *a, const mbedtls_x509_buf *b)
309 {
310 if (a->tag == b->tag &&
311 a->len == b->len &&
312 memcmp(a->p, b->p, b->len) == 0) {
313 return 0;
314 }
315
316 if ((a->tag == MBEDTLS_ASN1_UTF8_STRING || a->tag == MBEDTLS_ASN1_PRINTABLE_STRING) &&
317 (b->tag == MBEDTLS_ASN1_UTF8_STRING || b->tag == MBEDTLS_ASN1_PRINTABLE_STRING) &&
318 a->len == b->len &&
319 x509_memcasecmp(a->p, b->p, b->len) == 0) {
320 return 0;
321 }
322
323 return -1;
324 }
325
326 /*
327 * Compare two X.509 Names (aka rdnSequence).
328 *
329 * See RFC 5280 section 7.1, though we don't implement the whole algorithm:
330 * we sometimes return unequal when the full algorithm would return equal,
331 * but never the other way. (In particular, we don't do Unicode normalisation
332 * or space folding.)
333 *
334 * Return 0 if equal, -1 otherwise.
335 */
x509_name_cmp(const mbedtls_x509_name * a,const mbedtls_x509_name * b)336 static int x509_name_cmp(const mbedtls_x509_name *a, const mbedtls_x509_name *b)
337 {
338 /* Avoid recursion, it might not be optimised by the compiler */
339 while (a != NULL || b != NULL) {
340 if (a == NULL || b == NULL) {
341 return -1;
342 }
343
344 /* type */
345 if (a->oid.tag != b->oid.tag ||
346 a->oid.len != b->oid.len ||
347 memcmp(a->oid.p, b->oid.p, b->oid.len) != 0) {
348 return -1;
349 }
350
351 /* value */
352 if (x509_string_cmp(&a->val, &b->val) != 0) {
353 return -1;
354 }
355
356 /* structure of the list of sets */
357 if (a->next_merged != b->next_merged) {
358 return -1;
359 }
360
361 a = a->next;
362 b = b->next;
363 }
364
365 /* a == NULL == b */
366 return 0;
367 }
368
369 /*
370 * Reset (init or clear) a verify_chain
371 */
x509_crt_verify_chain_reset(mbedtls_x509_crt_verify_chain * ver_chain)372 static void x509_crt_verify_chain_reset(
373 mbedtls_x509_crt_verify_chain *ver_chain)
374 {
375 size_t i;
376
377 for (i = 0; i < MBEDTLS_X509_MAX_VERIFY_CHAIN_SIZE; i++) {
378 ver_chain->items[i].crt = NULL;
379 ver_chain->items[i].flags = (uint32_t) -1;
380 }
381
382 ver_chain->len = 0;
383
384 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
385 ver_chain->trust_ca_cb_result = NULL;
386 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
387 }
388
389 /*
390 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
391 */
x509_get_version(unsigned char ** p,const unsigned char * end,int * ver)392 static int x509_get_version(unsigned char **p,
393 const unsigned char *end,
394 int *ver)
395 {
396 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
397 size_t len;
398
399 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
400 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED |
401 0)) != 0) {
402 if (ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
403 *ver = 0;
404 return 0;
405 }
406
407 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
408 }
409
410 end = *p + len;
411
412 if ((ret = mbedtls_asn1_get_int(p, end, ver)) != 0) {
413 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_VERSION, ret);
414 }
415
416 if (*p != end) {
417 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_VERSION,
418 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
419 }
420
421 return 0;
422 }
423
424 /*
425 * Validity ::= SEQUENCE {
426 * notBefore Time,
427 * notAfter Time }
428 */
x509_get_dates(unsigned char ** p,const unsigned char * end,mbedtls_x509_time * from,mbedtls_x509_time * to)429 static int x509_get_dates(unsigned char **p,
430 const unsigned char *end,
431 mbedtls_x509_time *from,
432 mbedtls_x509_time *to)
433 {
434 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
435 size_t len;
436
437 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
438 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
439 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_DATE, ret);
440 }
441
442 end = *p + len;
443
444 if ((ret = mbedtls_x509_get_time(p, end, from)) != 0) {
445 return ret;
446 }
447
448 if ((ret = mbedtls_x509_get_time(p, end, to)) != 0) {
449 return ret;
450 }
451
452 if (*p != end) {
453 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_DATE,
454 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
455 }
456
457 return 0;
458 }
459
460 /*
461 * X.509 v2/v3 unique identifier (not parsed)
462 */
x509_get_uid(unsigned char ** p,const unsigned char * end,mbedtls_x509_buf * uid,int n)463 static int x509_get_uid(unsigned char **p,
464 const unsigned char *end,
465 mbedtls_x509_buf *uid, int n)
466 {
467 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
468
469 if (*p == end) {
470 return 0;
471 }
472
473 uid->tag = **p;
474
475 if ((ret = mbedtls_asn1_get_tag(p, end, &uid->len,
476 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED |
477 n)) != 0) {
478 if (ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
479 return 0;
480 }
481
482 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
483 }
484
485 uid->p = *p;
486 *p += uid->len;
487
488 return 0;
489 }
490
x509_get_basic_constraints(unsigned char ** p,const unsigned char * end,int * ca_istrue,int * max_pathlen)491 static int x509_get_basic_constraints(unsigned char **p,
492 const unsigned char *end,
493 int *ca_istrue,
494 int *max_pathlen)
495 {
496 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
497 size_t len;
498
499 /*
500 * BasicConstraints ::= SEQUENCE {
501 * cA BOOLEAN DEFAULT FALSE,
502 * pathLenConstraint INTEGER (0..MAX) OPTIONAL }
503 */
504 *ca_istrue = 0; /* DEFAULT FALSE */
505 *max_pathlen = 0; /* endless */
506
507 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
508 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
509 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
510 }
511
512 if (*p == end) {
513 return 0;
514 }
515
516 if ((ret = mbedtls_asn1_get_bool(p, end, ca_istrue)) != 0) {
517 if (ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
518 ret = mbedtls_asn1_get_int(p, end, ca_istrue);
519 }
520
521 if (ret != 0) {
522 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
523 }
524
525 if (*ca_istrue != 0) {
526 *ca_istrue = 1;
527 }
528 }
529
530 if (*p == end) {
531 return 0;
532 }
533
534 if ((ret = mbedtls_asn1_get_int(p, end, max_pathlen)) != 0) {
535 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
536 }
537
538 if (*p != end) {
539 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
540 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
541 }
542
543 /* Do not accept max_pathlen equal to INT_MAX to avoid a signed integer
544 * overflow, which is an undefined behavior. */
545 if (*max_pathlen == INT_MAX) {
546 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
547 MBEDTLS_ERR_ASN1_INVALID_LENGTH);
548 }
549
550 (*max_pathlen)++;
551
552 return 0;
553 }
554
555 /*
556 * ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId
557 *
558 * KeyPurposeId ::= OBJECT IDENTIFIER
559 */
x509_get_ext_key_usage(unsigned char ** p,const unsigned char * end,mbedtls_x509_sequence * ext_key_usage)560 static int x509_get_ext_key_usage(unsigned char **p,
561 const unsigned char *end,
562 mbedtls_x509_sequence *ext_key_usage)
563 {
564 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
565
566 if ((ret = mbedtls_asn1_get_sequence_of(p, end, ext_key_usage, MBEDTLS_ASN1_OID)) != 0) {
567 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
568 }
569
570 /* Sequence length must be >= 1 */
571 if (ext_key_usage->buf.p == NULL) {
572 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
573 MBEDTLS_ERR_ASN1_INVALID_LENGTH);
574 }
575
576 return 0;
577 }
578
579 /*
580 * SubjectKeyIdentifier ::= KeyIdentifier
581 *
582 * KeyIdentifier ::= OCTET STRING
583 */
x509_get_subject_key_id(unsigned char ** p,const unsigned char * end,mbedtls_x509_buf * subject_key_id)584 static int x509_get_subject_key_id(unsigned char **p,
585 const unsigned char *end,
586 mbedtls_x509_buf *subject_key_id)
587 {
588 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
589 size_t len = 0u;
590
591 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
592 MBEDTLS_ASN1_OCTET_STRING)) != 0) {
593 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
594 }
595
596 subject_key_id->len = len;
597 subject_key_id->tag = MBEDTLS_ASN1_OCTET_STRING;
598 subject_key_id->p = *p;
599 *p += len;
600
601 if (*p != end) {
602 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
603 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
604 }
605
606 return 0;
607 }
608
609 /*
610 * AuthorityKeyIdentifier ::= SEQUENCE {
611 * keyIdentifier [0] KeyIdentifier OPTIONAL,
612 * authorityCertIssuer [1] GeneralNames OPTIONAL,
613 * authorityCertSerialNumber [2] CertificateSerialNumber OPTIONAL }
614 *
615 * KeyIdentifier ::= OCTET STRING
616 */
x509_get_authority_key_id(unsigned char ** p,unsigned char * end,mbedtls_x509_authority * authority_key_id)617 static int x509_get_authority_key_id(unsigned char **p,
618 unsigned char *end,
619 mbedtls_x509_authority *authority_key_id)
620 {
621 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
622 size_t len = 0u;
623
624 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
625 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
626 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
627 }
628
629 if (*p + len != end) {
630 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
631 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
632 }
633
634 ret = mbedtls_asn1_get_tag(p, end, &len,
635 MBEDTLS_ASN1_CONTEXT_SPECIFIC);
636
637 /* KeyIdentifier is an OPTIONAL field */
638 if (ret == 0) {
639 authority_key_id->keyIdentifier.len = len;
640 authority_key_id->keyIdentifier.p = *p;
641 /* Setting tag of the keyIdentfier intentionally to 0x04.
642 * Although the .keyIdentfier field is CONTEXT_SPECIFIC ([0] OPTIONAL),
643 * its tag with the content is the payload of on OCTET STRING primitive */
644 authority_key_id->keyIdentifier.tag = MBEDTLS_ASN1_OCTET_STRING;
645
646 *p += len;
647 } else if (ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
648 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
649 }
650
651 if (*p < end) {
652 /* Getting authorityCertIssuer using the required specific class tag [1] */
653 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
654 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED |
655 1)) != 0) {
656 /* authorityCertIssuer and authorityCertSerialNumber MUST both
657 be present or both be absent. At this point we expect to have both. */
658 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
659 }
660 /* "end" also includes the CertSerialNumber field so "len" shall be used */
661 ret = mbedtls_x509_get_subject_alt_name_ext(p,
662 (*p+len),
663 &authority_key_id->authorityCertIssuer);
664 if (ret != 0) {
665 return ret;
666 }
667
668 /* Getting authorityCertSerialNumber using the required specific class tag [2] */
669 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
670 MBEDTLS_ASN1_CONTEXT_SPECIFIC | 2)) != 0) {
671 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
672 }
673 authority_key_id->authorityCertSerialNumber.len = len;
674 authority_key_id->authorityCertSerialNumber.p = *p;
675 authority_key_id->authorityCertSerialNumber.tag = MBEDTLS_ASN1_INTEGER;
676 *p += len;
677 }
678
679 if (*p != end) {
680 return MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
681 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
682 }
683
684 return 0;
685 }
686
687 /*
688 * id-ce-certificatePolicies OBJECT IDENTIFIER ::= { id-ce 32 }
689 *
690 * anyPolicy OBJECT IDENTIFIER ::= { id-ce-certificatePolicies 0 }
691 *
692 * certificatePolicies ::= SEQUENCE SIZE (1..MAX) OF PolicyInformation
693 *
694 * PolicyInformation ::= SEQUENCE {
695 * policyIdentifier CertPolicyId,
696 * policyQualifiers SEQUENCE SIZE (1..MAX) OF
697 * PolicyQualifierInfo OPTIONAL }
698 *
699 * CertPolicyId ::= OBJECT IDENTIFIER
700 *
701 * PolicyQualifierInfo ::= SEQUENCE {
702 * policyQualifierId PolicyQualifierId,
703 * qualifier ANY DEFINED BY policyQualifierId }
704 *
705 * -- policyQualifierIds for Internet policy qualifiers
706 *
707 * id-qt OBJECT IDENTIFIER ::= { id-pkix 2 }
708 * id-qt-cps OBJECT IDENTIFIER ::= { id-qt 1 }
709 * id-qt-unotice OBJECT IDENTIFIER ::= { id-qt 2 }
710 *
711 * PolicyQualifierId ::= OBJECT IDENTIFIER ( id-qt-cps | id-qt-unotice )
712 *
713 * Qualifier ::= CHOICE {
714 * cPSuri CPSuri,
715 * userNotice UserNotice }
716 *
717 * CPSuri ::= IA5String
718 *
719 * UserNotice ::= SEQUENCE {
720 * noticeRef NoticeReference OPTIONAL,
721 * explicitText DisplayText OPTIONAL }
722 *
723 * NoticeReference ::= SEQUENCE {
724 * organization DisplayText,
725 * noticeNumbers SEQUENCE OF INTEGER }
726 *
727 * DisplayText ::= CHOICE {
728 * ia5String IA5String (SIZE (1..200)),
729 * visibleString VisibleString (SIZE (1..200)),
730 * bmpString BMPString (SIZE (1..200)),
731 * utf8String UTF8String (SIZE (1..200)) }
732 *
733 * NOTE: we only parse and use anyPolicy without qualifiers at this point
734 * as defined in RFC 5280.
735 */
x509_get_certificate_policies(unsigned char ** p,const unsigned char * end,mbedtls_x509_sequence * certificate_policies)736 static int x509_get_certificate_policies(unsigned char **p,
737 const unsigned char *end,
738 mbedtls_x509_sequence *certificate_policies)
739 {
740 int ret, parse_ret = 0;
741 size_t len;
742 mbedtls_asn1_buf *buf;
743 mbedtls_asn1_sequence *cur = certificate_policies;
744
745 /* Get main sequence tag */
746 ret = mbedtls_asn1_get_tag(p, end, &len,
747 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
748 if (ret != 0) {
749 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
750 }
751
752 if (*p + len != end) {
753 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
754 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
755 }
756
757 /*
758 * Cannot be an empty sequence.
759 */
760 if (len == 0) {
761 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
762 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
763 }
764
765 while (*p < end) {
766 mbedtls_x509_buf policy_oid;
767 const unsigned char *policy_end;
768
769 /*
770 * Get the policy sequence
771 */
772 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
773 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
774 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
775 }
776
777 policy_end = *p + len;
778
779 if ((ret = mbedtls_asn1_get_tag(p, policy_end, &len,
780 MBEDTLS_ASN1_OID)) != 0) {
781 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
782 }
783
784 policy_oid.tag = MBEDTLS_ASN1_OID;
785 policy_oid.len = len;
786 policy_oid.p = *p;
787
788 /*
789 * Only AnyPolicy is currently supported when enforcing policy.
790 */
791 if (MBEDTLS_OID_CMP(MBEDTLS_OID_ANY_POLICY, &policy_oid) != 0) {
792 /*
793 * Set the parsing return code but continue parsing, in case this
794 * extension is critical.
795 */
796 parse_ret = MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
797 }
798
799 /* Allocate and assign next pointer */
800 if (cur->buf.p != NULL) {
801 if (cur->next != NULL) {
802 return MBEDTLS_ERR_X509_INVALID_EXTENSIONS;
803 }
804
805 cur->next = mbedtls_calloc(1, sizeof(mbedtls_asn1_sequence));
806
807 if (cur->next == NULL) {
808 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
809 MBEDTLS_ERR_ASN1_ALLOC_FAILED);
810 }
811
812 cur = cur->next;
813 }
814
815 buf = &(cur->buf);
816 buf->tag = policy_oid.tag;
817 buf->p = policy_oid.p;
818 buf->len = policy_oid.len;
819
820 *p += len;
821
822 /*
823 * If there is an optional qualifier, then *p < policy_end
824 * Check the Qualifier len to verify it doesn't exceed policy_end.
825 */
826 if (*p < policy_end) {
827 if ((ret = mbedtls_asn1_get_tag(p, policy_end, &len,
828 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) !=
829 0) {
830 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
831 }
832 /*
833 * Skip the optional policy qualifiers.
834 */
835 *p += len;
836 }
837
838 if (*p != policy_end) {
839 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
840 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
841 }
842 }
843
844 /* Set final sequence entry's next pointer to NULL */
845 cur->next = NULL;
846
847 if (*p != end) {
848 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
849 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
850 }
851
852 return parse_ret;
853 }
854
855 /*
856 * X.509 v3 extensions
857 *
858 */
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)859 static int x509_get_crt_ext(unsigned char **p,
860 const unsigned char *end,
861 mbedtls_x509_crt *crt,
862 mbedtls_x509_crt_ext_cb_t cb,
863 void *p_ctx)
864 {
865 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
866 size_t len;
867 unsigned char *end_ext_data, *start_ext_octet, *end_ext_octet;
868
869 if (*p == end) {
870 return 0;
871 }
872
873 if ((ret = mbedtls_x509_get_ext(p, end, &crt->v3_ext, 3)) != 0) {
874 return ret;
875 }
876
877 end = crt->v3_ext.p + crt->v3_ext.len;
878 while (*p < end) {
879 /*
880 * Extension ::= SEQUENCE {
881 * extnID OBJECT IDENTIFIER,
882 * critical BOOLEAN DEFAULT FALSE,
883 * extnValue OCTET STRING }
884 */
885 mbedtls_x509_buf extn_oid = { 0, 0, NULL };
886 int is_critical = 0; /* DEFAULT FALSE */
887 int ext_type = 0;
888
889 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
890 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
891 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
892 }
893
894 end_ext_data = *p + len;
895
896 /* Get extension ID */
897 if ((ret = mbedtls_asn1_get_tag(p, end_ext_data, &extn_oid.len,
898 MBEDTLS_ASN1_OID)) != 0) {
899 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
900 }
901
902 extn_oid.tag = MBEDTLS_ASN1_OID;
903 extn_oid.p = *p;
904 *p += extn_oid.len;
905
906 /* Get optional critical */
907 if ((ret = mbedtls_asn1_get_bool(p, end_ext_data, &is_critical)) != 0 &&
908 (ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG)) {
909 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
910 }
911
912 /* Data should be octet string type */
913 if ((ret = mbedtls_asn1_get_tag(p, end_ext_data, &len,
914 MBEDTLS_ASN1_OCTET_STRING)) != 0) {
915 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
916 }
917
918 start_ext_octet = *p;
919 end_ext_octet = *p + len;
920
921 if (end_ext_octet != end_ext_data) {
922 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
923 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
924 }
925
926 /*
927 * Detect supported extensions
928 */
929 ret = mbedtls_oid_get_x509_ext_type(&extn_oid, &ext_type);
930
931 if (ret != 0) {
932 /* Give the callback (if any) a chance to handle the extension */
933 if (cb != NULL) {
934 ret = cb(p_ctx, crt, &extn_oid, is_critical, *p, end_ext_octet);
935 if (ret != 0 && is_critical) {
936 return ret;
937 }
938 *p = end_ext_octet;
939 continue;
940 }
941
942 /* No parser found, skip extension */
943 *p = end_ext_octet;
944
945 if (is_critical) {
946 /* Data is marked as critical: fail */
947 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
948 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
949 }
950 continue;
951 }
952
953 /* Forbid repeated extensions */
954 if ((crt->ext_types & ext_type) != 0) {
955 return MBEDTLS_ERR_X509_INVALID_EXTENSIONS;
956 }
957
958 crt->ext_types |= ext_type;
959
960 switch (ext_type) {
961 case MBEDTLS_X509_EXT_BASIC_CONSTRAINTS:
962 /* Parse basic constraints */
963 if ((ret = x509_get_basic_constraints(p, end_ext_octet,
964 &crt->ca_istrue, &crt->max_pathlen)) != 0) {
965 return ret;
966 }
967 break;
968
969 case MBEDTLS_X509_EXT_KEY_USAGE:
970 /* Parse key usage */
971 if ((ret = mbedtls_x509_get_key_usage(p, end_ext_octet,
972 &crt->key_usage)) != 0) {
973 return ret;
974 }
975 break;
976
977 case MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE:
978 /* Parse extended key usage */
979 if ((ret = x509_get_ext_key_usage(p, end_ext_octet,
980 &crt->ext_key_usage)) != 0) {
981 return ret;
982 }
983 break;
984
985 case MBEDTLS_X509_EXT_SUBJECT_KEY_IDENTIFIER:
986 /* Parse subject key identifier */
987 if ((ret = x509_get_subject_key_id(p, end_ext_data,
988 &crt->subject_key_id)) != 0) {
989 return ret;
990 }
991 break;
992
993 case MBEDTLS_X509_EXT_AUTHORITY_KEY_IDENTIFIER:
994 /* Parse authority key identifier */
995 if ((ret = x509_get_authority_key_id(p, end_ext_octet,
996 &crt->authority_key_id)) != 0) {
997 return ret;
998 }
999 break;
1000 case MBEDTLS_X509_EXT_SUBJECT_ALT_NAME:
1001 /* Parse subject alt name
1002 * SubjectAltName ::= GeneralNames
1003 */
1004 if ((ret = mbedtls_x509_get_subject_alt_name(p, end_ext_octet,
1005 &crt->subject_alt_names)) != 0) {
1006 return ret;
1007 }
1008 break;
1009
1010 case MBEDTLS_X509_EXT_NS_CERT_TYPE:
1011 /* Parse netscape certificate type */
1012 if ((ret = mbedtls_x509_get_ns_cert_type(p, end_ext_octet,
1013 &crt->ns_cert_type)) != 0) {
1014 return ret;
1015 }
1016 break;
1017
1018 case MBEDTLS_OID_X509_EXT_CERTIFICATE_POLICIES:
1019 /* Parse certificate policies type */
1020 if ((ret = x509_get_certificate_policies(p, end_ext_octet,
1021 &crt->certificate_policies)) != 0) {
1022 /* Give the callback (if any) a chance to handle the extension
1023 * if it contains unsupported policies */
1024 if (ret == MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE && cb != NULL &&
1025 cb(p_ctx, crt, &extn_oid, is_critical,
1026 start_ext_octet, end_ext_octet) == 0) {
1027 break;
1028 }
1029
1030 if (is_critical) {
1031 return ret;
1032 } else
1033 /*
1034 * If MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE is returned, then we
1035 * cannot interpret or enforce the policy. However, it is up to
1036 * the user to choose how to enforce the policies,
1037 * unless the extension is critical.
1038 */
1039 if (ret != MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE) {
1040 return ret;
1041 }
1042 }
1043 break;
1044
1045 default:
1046 /*
1047 * If this is a non-critical extension, which the oid layer
1048 * supports, but there isn't an x509 parser for it,
1049 * skip the extension.
1050 */
1051 if (is_critical) {
1052 return MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
1053 } else {
1054 *p = end_ext_octet;
1055 }
1056 }
1057 }
1058
1059 if (*p != end) {
1060 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
1061 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
1062 }
1063
1064 return 0;
1065 }
1066
1067 /*
1068 * Parse and fill a single X.509 certificate in DER format
1069 */
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)1070 static int x509_crt_parse_der_core(mbedtls_x509_crt *crt,
1071 const unsigned char *buf,
1072 size_t buflen,
1073 int make_copy,
1074 mbedtls_x509_crt_ext_cb_t cb,
1075 void *p_ctx)
1076 {
1077 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1078 size_t len;
1079 unsigned char *p, *end, *crt_end;
1080 mbedtls_x509_buf sig_params1, sig_params2, sig_oid2;
1081
1082 memset(&sig_params1, 0, sizeof(mbedtls_x509_buf));
1083 memset(&sig_params2, 0, sizeof(mbedtls_x509_buf));
1084 memset(&sig_oid2, 0, sizeof(mbedtls_x509_buf));
1085
1086 /*
1087 * Check for valid input
1088 */
1089 if (crt == NULL || buf == NULL) {
1090 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1091 }
1092
1093 /* Use the original buffer until we figure out actual length. */
1094 p = (unsigned char *) buf;
1095 len = buflen;
1096 end = p + len;
1097
1098 /*
1099 * Certificate ::= SEQUENCE {
1100 * tbsCertificate TBSCertificate,
1101 * signatureAlgorithm AlgorithmIdentifier,
1102 * signatureValue BIT STRING }
1103 */
1104 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
1105 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
1106 mbedtls_x509_crt_free(crt);
1107 return MBEDTLS_ERR_X509_INVALID_FORMAT;
1108 }
1109
1110 end = crt_end = p + len;
1111 crt->raw.len = crt_end - buf;
1112 if (make_copy != 0) {
1113 /* Create and populate a new buffer for the raw field. */
1114 crt->raw.p = p = mbedtls_calloc(1, crt->raw.len);
1115 if (crt->raw.p == NULL) {
1116 return MBEDTLS_ERR_X509_ALLOC_FAILED;
1117 }
1118
1119 memcpy(crt->raw.p, buf, crt->raw.len);
1120 crt->own_buffer = 1;
1121
1122 p += crt->raw.len - len;
1123 end = crt_end = p + len;
1124 } else {
1125 crt->raw.p = (unsigned char *) buf;
1126 crt->own_buffer = 0;
1127 }
1128
1129 /*
1130 * TBSCertificate ::= SEQUENCE {
1131 */
1132 crt->tbs.p = p;
1133
1134 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
1135 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
1136 mbedtls_x509_crt_free(crt);
1137 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
1138 }
1139
1140 end = p + len;
1141 crt->tbs.len = end - crt->tbs.p;
1142
1143 /*
1144 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
1145 *
1146 * CertificateSerialNumber ::= INTEGER
1147 *
1148 * signature AlgorithmIdentifier
1149 */
1150 if ((ret = x509_get_version(&p, end, &crt->version)) != 0 ||
1151 (ret = mbedtls_x509_get_serial(&p, end, &crt->serial)) != 0 ||
1152 (ret = mbedtls_x509_get_alg(&p, end, &crt->sig_oid,
1153 &sig_params1)) != 0) {
1154 mbedtls_x509_crt_free(crt);
1155 return ret;
1156 }
1157
1158 if (crt->version < 0 || crt->version > 2) {
1159 mbedtls_x509_crt_free(crt);
1160 return MBEDTLS_ERR_X509_UNKNOWN_VERSION;
1161 }
1162
1163 crt->version++;
1164
1165 if ((ret = mbedtls_x509_get_sig_alg(&crt->sig_oid, &sig_params1,
1166 &crt->sig_md, &crt->sig_pk,
1167 &crt->sig_opts)) != 0) {
1168 mbedtls_x509_crt_free(crt);
1169 return ret;
1170 }
1171
1172 /*
1173 * issuer Name
1174 */
1175 crt->issuer_raw.p = p;
1176
1177 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
1178 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
1179 mbedtls_x509_crt_free(crt);
1180 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
1181 }
1182
1183 if ((ret = mbedtls_x509_get_name(&p, p + len, &crt->issuer)) != 0) {
1184 mbedtls_x509_crt_free(crt);
1185 return ret;
1186 }
1187
1188 crt->issuer_raw.len = p - crt->issuer_raw.p;
1189
1190 /*
1191 * Validity ::= SEQUENCE {
1192 * notBefore Time,
1193 * notAfter Time }
1194 *
1195 */
1196 if ((ret = x509_get_dates(&p, end, &crt->valid_from,
1197 &crt->valid_to)) != 0) {
1198 mbedtls_x509_crt_free(crt);
1199 return ret;
1200 }
1201
1202 /*
1203 * subject Name
1204 */
1205 crt->subject_raw.p = p;
1206
1207 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
1208 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
1209 mbedtls_x509_crt_free(crt);
1210 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
1211 }
1212
1213 if (len && (ret = mbedtls_x509_get_name(&p, p + len, &crt->subject)) != 0) {
1214 mbedtls_x509_crt_free(crt);
1215 return ret;
1216 }
1217
1218 crt->subject_raw.len = p - crt->subject_raw.p;
1219
1220 /*
1221 * SubjectPublicKeyInfo
1222 */
1223 crt->pk_raw.p = p;
1224 if ((ret = mbedtls_pk_parse_subpubkey(&p, end, &crt->pk)) != 0) {
1225 mbedtls_x509_crt_free(crt);
1226 return ret;
1227 }
1228 crt->pk_raw.len = p - crt->pk_raw.p;
1229
1230 /*
1231 * issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
1232 * -- If present, version shall be v2 or v3
1233 * subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
1234 * -- If present, version shall be v2 or v3
1235 * extensions [3] EXPLICIT Extensions OPTIONAL
1236 * -- If present, version shall be v3
1237 */
1238 if (crt->version == 2 || crt->version == 3) {
1239 ret = x509_get_uid(&p, end, &crt->issuer_id, 1);
1240 if (ret != 0) {
1241 mbedtls_x509_crt_free(crt);
1242 return ret;
1243 }
1244 }
1245
1246 if (crt->version == 2 || crt->version == 3) {
1247 ret = x509_get_uid(&p, end, &crt->subject_id, 2);
1248 if (ret != 0) {
1249 mbedtls_x509_crt_free(crt);
1250 return ret;
1251 }
1252 }
1253
1254 if (crt->version == 3) {
1255 ret = x509_get_crt_ext(&p, end, crt, cb, p_ctx);
1256 if (ret != 0) {
1257 mbedtls_x509_crt_free(crt);
1258 return ret;
1259 }
1260 }
1261
1262 if (p != end) {
1263 mbedtls_x509_crt_free(crt);
1264 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT,
1265 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
1266 }
1267
1268 end = crt_end;
1269
1270 /*
1271 * }
1272 * -- end of TBSCertificate
1273 *
1274 * signatureAlgorithm AlgorithmIdentifier,
1275 * signatureValue BIT STRING
1276 */
1277 if ((ret = mbedtls_x509_get_alg(&p, end, &sig_oid2, &sig_params2)) != 0) {
1278 mbedtls_x509_crt_free(crt);
1279 return ret;
1280 }
1281
1282 if (crt->sig_oid.len != sig_oid2.len ||
1283 memcmp(crt->sig_oid.p, sig_oid2.p, crt->sig_oid.len) != 0 ||
1284 sig_params1.tag != sig_params2.tag ||
1285 sig_params1.len != sig_params2.len ||
1286 (sig_params1.len != 0 &&
1287 memcmp(sig_params1.p, sig_params2.p, sig_params1.len) != 0)) {
1288 mbedtls_x509_crt_free(crt);
1289 return MBEDTLS_ERR_X509_SIG_MISMATCH;
1290 }
1291
1292 if ((ret = mbedtls_x509_get_sig(&p, end, &crt->sig)) != 0) {
1293 mbedtls_x509_crt_free(crt);
1294 return ret;
1295 }
1296
1297 if (p != end) {
1298 mbedtls_x509_crt_free(crt);
1299 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT,
1300 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
1301 }
1302
1303 return 0;
1304 }
1305
1306 /*
1307 * Parse one X.509 certificate in DER format from a buffer and add them to a
1308 * chained list
1309 */
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)1310 static int mbedtls_x509_crt_parse_der_internal(mbedtls_x509_crt *chain,
1311 const unsigned char *buf,
1312 size_t buflen,
1313 int make_copy,
1314 mbedtls_x509_crt_ext_cb_t cb,
1315 void *p_ctx)
1316 {
1317 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1318 mbedtls_x509_crt *crt = chain, *prev = NULL;
1319
1320 /*
1321 * Check for valid input
1322 */
1323 if (crt == NULL || buf == NULL) {
1324 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1325 }
1326
1327 while (crt->version != 0 && crt->next != NULL) {
1328 prev = crt;
1329 crt = crt->next;
1330 }
1331
1332 /*
1333 * Add new certificate on the end of the chain if needed.
1334 */
1335 if (crt->version != 0 && crt->next == NULL) {
1336 crt->next = mbedtls_calloc(1, sizeof(mbedtls_x509_crt));
1337
1338 if (crt->next == NULL) {
1339 return MBEDTLS_ERR_X509_ALLOC_FAILED;
1340 }
1341
1342 prev = crt;
1343 mbedtls_x509_crt_init(crt->next);
1344 crt = crt->next;
1345 }
1346
1347 ret = x509_crt_parse_der_core(crt, buf, buflen, make_copy, cb, p_ctx);
1348 if (ret != 0) {
1349 if (prev) {
1350 prev->next = NULL;
1351 }
1352
1353 if (crt != chain) {
1354 mbedtls_free(crt);
1355 }
1356
1357 return ret;
1358 }
1359
1360 return 0;
1361 }
1362
mbedtls_x509_crt_parse_der_nocopy(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)1363 int mbedtls_x509_crt_parse_der_nocopy(mbedtls_x509_crt *chain,
1364 const unsigned char *buf,
1365 size_t buflen)
1366 {
1367 return mbedtls_x509_crt_parse_der_internal(chain, buf, buflen, 0, NULL, NULL);
1368 }
1369
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)1370 int mbedtls_x509_crt_parse_der_with_ext_cb(mbedtls_x509_crt *chain,
1371 const unsigned char *buf,
1372 size_t buflen,
1373 int make_copy,
1374 mbedtls_x509_crt_ext_cb_t cb,
1375 void *p_ctx)
1376 {
1377 return mbedtls_x509_crt_parse_der_internal(chain, buf, buflen, make_copy, cb, p_ctx);
1378 }
1379
mbedtls_x509_crt_parse_der(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)1380 int mbedtls_x509_crt_parse_der(mbedtls_x509_crt *chain,
1381 const unsigned char *buf,
1382 size_t buflen)
1383 {
1384 return mbedtls_x509_crt_parse_der_internal(chain, buf, buflen, 1, NULL, NULL);
1385 }
1386
1387 /*
1388 * Parse one or more PEM certificates from a buffer and add them to the chained
1389 * list
1390 */
mbedtls_x509_crt_parse(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)1391 int mbedtls_x509_crt_parse(mbedtls_x509_crt *chain,
1392 const unsigned char *buf,
1393 size_t buflen)
1394 {
1395 #if defined(MBEDTLS_PEM_PARSE_C)
1396 int success = 0, first_error = 0, total_failed = 0;
1397 int buf_format = MBEDTLS_X509_FORMAT_DER;
1398 #endif
1399
1400 /*
1401 * Check for valid input
1402 */
1403 if (chain == NULL || buf == NULL) {
1404 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1405 }
1406
1407 /*
1408 * Determine buffer content. Buffer contains either one DER certificate or
1409 * one or more PEM certificates.
1410 */
1411 #if defined(MBEDTLS_PEM_PARSE_C)
1412 if (buflen != 0 && buf[buflen - 1] == '\0' &&
1413 strstr((const char *) buf, "-----BEGIN CERTIFICATE-----") != NULL) {
1414 buf_format = MBEDTLS_X509_FORMAT_PEM;
1415 }
1416
1417 if (buf_format == MBEDTLS_X509_FORMAT_DER) {
1418 return mbedtls_x509_crt_parse_der(chain, buf, buflen);
1419 }
1420 #else
1421 return mbedtls_x509_crt_parse_der(chain, buf, buflen);
1422 #endif
1423
1424 #if defined(MBEDTLS_PEM_PARSE_C)
1425 if (buf_format == MBEDTLS_X509_FORMAT_PEM) {
1426 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1427 mbedtls_pem_context pem;
1428
1429 /* 1 rather than 0 since the terminating NULL byte is counted in */
1430 while (buflen > 1) {
1431 size_t use_len;
1432 mbedtls_pem_init(&pem);
1433
1434 /* If we get there, we know the string is null-terminated */
1435 ret = mbedtls_pem_read_buffer(&pem,
1436 "-----BEGIN CERTIFICATE-----",
1437 "-----END CERTIFICATE-----",
1438 buf, NULL, 0, &use_len);
1439
1440 if (ret == 0) {
1441 /*
1442 * Was PEM encoded
1443 */
1444 buflen -= use_len;
1445 buf += use_len;
1446 } else if (ret == MBEDTLS_ERR_PEM_BAD_INPUT_DATA) {
1447 return ret;
1448 } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
1449 mbedtls_pem_free(&pem);
1450
1451 /*
1452 * PEM header and footer were found
1453 */
1454 buflen -= use_len;
1455 buf += use_len;
1456
1457 if (first_error == 0) {
1458 first_error = ret;
1459 }
1460
1461 total_failed++;
1462 continue;
1463 } else {
1464 break;
1465 }
1466
1467 ret = mbedtls_x509_crt_parse_der(chain, pem.buf, pem.buflen);
1468
1469 mbedtls_pem_free(&pem);
1470
1471 if (ret != 0) {
1472 /*
1473 * Quit parsing on a memory error
1474 */
1475 if (ret == MBEDTLS_ERR_X509_ALLOC_FAILED) {
1476 return ret;
1477 }
1478
1479 if (first_error == 0) {
1480 first_error = ret;
1481 }
1482
1483 total_failed++;
1484 continue;
1485 }
1486
1487 success = 1;
1488 }
1489 }
1490
1491 if (success) {
1492 return total_failed;
1493 } else if (first_error) {
1494 return first_error;
1495 } else {
1496 return MBEDTLS_ERR_X509_CERT_UNKNOWN_FORMAT;
1497 }
1498 #endif /* MBEDTLS_PEM_PARSE_C */
1499 }
1500
1501 #if defined(MBEDTLS_FS_IO)
1502 /*
1503 * Load one or more certificates and add them to the chained list
1504 */
mbedtls_x509_crt_parse_file(mbedtls_x509_crt * chain,const char * path)1505 int mbedtls_x509_crt_parse_file(mbedtls_x509_crt *chain, const char *path)
1506 {
1507 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1508 size_t n;
1509 unsigned char *buf;
1510
1511 if ((ret = mbedtls_pk_load_file(path, &buf, &n)) != 0) {
1512 return ret;
1513 }
1514
1515 ret = mbedtls_x509_crt_parse(chain, buf, n);
1516
1517 mbedtls_zeroize_and_free(buf, n);
1518
1519 return ret;
1520 }
1521
mbedtls_x509_crt_parse_path(mbedtls_x509_crt * chain,const char * path)1522 int mbedtls_x509_crt_parse_path(mbedtls_x509_crt *chain, const char *path)
1523 {
1524 int ret = 0;
1525 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
1526 int w_ret;
1527 WCHAR szDir[MAX_PATH];
1528 char filename[MAX_PATH];
1529 char *p;
1530 size_t len = strlen(path);
1531
1532 WIN32_FIND_DATAW file_data;
1533 HANDLE hFind;
1534
1535 if (len > MAX_PATH - 3) {
1536 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1537 }
1538
1539 memset(szDir, 0, sizeof(szDir));
1540 memset(filename, 0, MAX_PATH);
1541 memcpy(filename, path, len);
1542 filename[len++] = '\\';
1543 p = filename + len;
1544 filename[len++] = '*';
1545
1546 /*
1547 * Note this function uses the code page CP_ACP which is the system default
1548 * ANSI codepage. The input string is always described in BYTES and the
1549 * output length is described in WCHARs.
1550 */
1551 w_ret = MultiByteToWideChar(CP_ACP, 0, filename, (int) len, szDir,
1552 MAX_PATH - 3);
1553 if (w_ret == 0) {
1554 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1555 }
1556
1557 hFind = FindFirstFileW(szDir, &file_data);
1558 if (hFind == INVALID_HANDLE_VALUE) {
1559 return MBEDTLS_ERR_X509_FILE_IO_ERROR;
1560 }
1561
1562 len = MAX_PATH - len;
1563 do {
1564 memset(p, 0, len);
1565
1566 if (file_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
1567 continue;
1568 }
1569 w_ret = WideCharToMultiByte(CP_ACP, 0, file_data.cFileName,
1570 -1, p, (int) len, NULL, NULL);
1571 if (w_ret == 0) {
1572 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1573 goto cleanup;
1574 }
1575
1576 w_ret = mbedtls_x509_crt_parse_file(chain, filename);
1577 if (w_ret < 0) {
1578 ret++;
1579 } else {
1580 ret += w_ret;
1581 }
1582 } while (FindNextFileW(hFind, &file_data) != 0);
1583
1584 if (GetLastError() != ERROR_NO_MORE_FILES) {
1585 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1586 }
1587
1588 cleanup:
1589 FindClose(hFind);
1590 #else /* _WIN32 */
1591 int t_ret;
1592 int snp_ret;
1593 struct stat sb;
1594 struct dirent *entry;
1595 char entry_name[MBEDTLS_X509_MAX_FILE_PATH_LEN];
1596 DIR *dir = opendir(path);
1597
1598 if (dir == NULL) {
1599 return MBEDTLS_ERR_X509_FILE_IO_ERROR;
1600 }
1601
1602 #if defined(MBEDTLS_THREADING_C)
1603 if ((ret = mbedtls_mutex_lock(&mbedtls_threading_readdir_mutex)) != 0) {
1604 closedir(dir);
1605 return ret;
1606 }
1607 #endif /* MBEDTLS_THREADING_C */
1608
1609 memset(&sb, 0, sizeof(sb));
1610
1611 while ((entry = readdir(dir)) != NULL) {
1612 snp_ret = mbedtls_snprintf(entry_name, sizeof(entry_name),
1613 "%s/%s", path, entry->d_name);
1614
1615 if (snp_ret < 0 || (size_t) snp_ret >= sizeof(entry_name)) {
1616 ret = MBEDTLS_ERR_X509_BUFFER_TOO_SMALL;
1617 goto cleanup;
1618 } else if (stat(entry_name, &sb) == -1) {
1619 if (errno == ENOENT) {
1620 /* Broken symbolic link - ignore this entry.
1621 stat(2) will return this error for either (a) a dangling
1622 symlink or (b) a missing file.
1623 Given that we have just obtained the filename from readdir,
1624 assume that it does exist and therefore treat this as a
1625 dangling symlink. */
1626 continue;
1627 } else {
1628 /* Some other file error; report the error. */
1629 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1630 goto cleanup;
1631 }
1632 }
1633
1634 if (!S_ISREG(sb.st_mode)) {
1635 continue;
1636 }
1637
1638 // Ignore parse errors
1639 //
1640 t_ret = mbedtls_x509_crt_parse_file(chain, entry_name);
1641 if (t_ret < 0) {
1642 ret++;
1643 } else {
1644 ret += t_ret;
1645 }
1646 }
1647
1648 cleanup:
1649 closedir(dir);
1650
1651 #if defined(MBEDTLS_THREADING_C)
1652 if (mbedtls_mutex_unlock(&mbedtls_threading_readdir_mutex) != 0) {
1653 ret = MBEDTLS_ERR_THREADING_MUTEX_ERROR;
1654 }
1655 #endif /* MBEDTLS_THREADING_C */
1656
1657 #endif /* _WIN32 */
1658
1659 return ret;
1660 }
1661 #endif /* MBEDTLS_FS_IO */
1662
1663 #if !defined(MBEDTLS_X509_REMOVE_INFO)
1664 #define PRINT_ITEM(i) \
1665 do { \
1666 ret = mbedtls_snprintf(p, n, "%s" i, sep); \
1667 MBEDTLS_X509_SAFE_SNPRINTF; \
1668 sep = ", "; \
1669 } while (0)
1670
1671 #define CERT_TYPE(type, name) \
1672 do { \
1673 if (ns_cert_type & (type)) { \
1674 PRINT_ITEM(name); \
1675 } \
1676 } while (0)
1677
1678 #define KEY_USAGE(code, name) \
1679 do { \
1680 if (key_usage & (code)) { \
1681 PRINT_ITEM(name); \
1682 } \
1683 } while (0)
1684
x509_info_ext_key_usage(char ** buf,size_t * size,const mbedtls_x509_sequence * extended_key_usage)1685 static int x509_info_ext_key_usage(char **buf, size_t *size,
1686 const mbedtls_x509_sequence *extended_key_usage)
1687 {
1688 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1689 const char *desc;
1690 size_t n = *size;
1691 char *p = *buf;
1692 const mbedtls_x509_sequence *cur = extended_key_usage;
1693 const char *sep = "";
1694
1695 while (cur != NULL) {
1696 if (mbedtls_oid_get_extended_key_usage(&cur->buf, &desc) != 0) {
1697 desc = "???";
1698 }
1699
1700 ret = mbedtls_snprintf(p, n, "%s%s", sep, desc);
1701 MBEDTLS_X509_SAFE_SNPRINTF;
1702
1703 sep = ", ";
1704
1705 cur = cur->next;
1706 }
1707
1708 *size = n;
1709 *buf = p;
1710
1711 return 0;
1712 }
1713
x509_info_cert_policies(char ** buf,size_t * size,const mbedtls_x509_sequence * certificate_policies)1714 static int x509_info_cert_policies(char **buf, size_t *size,
1715 const mbedtls_x509_sequence *certificate_policies)
1716 {
1717 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1718 const char *desc;
1719 size_t n = *size;
1720 char *p = *buf;
1721 const mbedtls_x509_sequence *cur = certificate_policies;
1722 const char *sep = "";
1723
1724 while (cur != NULL) {
1725 if (mbedtls_oid_get_certificate_policies(&cur->buf, &desc) != 0) {
1726 desc = "???";
1727 }
1728
1729 ret = mbedtls_snprintf(p, n, "%s%s", sep, desc);
1730 MBEDTLS_X509_SAFE_SNPRINTF;
1731
1732 sep = ", ";
1733
1734 cur = cur->next;
1735 }
1736
1737 *size = n;
1738 *buf = p;
1739
1740 return 0;
1741 }
1742
1743 /*
1744 * Return an informational string about the certificate.
1745 */
1746 #define BEFORE_COLON 18
1747 #define BC "18"
mbedtls_x509_crt_info(char * buf,size_t size,const char * prefix,const mbedtls_x509_crt * crt)1748 int mbedtls_x509_crt_info(char *buf, size_t size, const char *prefix,
1749 const mbedtls_x509_crt *crt)
1750 {
1751 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1752 size_t n;
1753 char *p;
1754 char key_size_str[BEFORE_COLON];
1755
1756 p = buf;
1757 n = size;
1758
1759 if (NULL == crt) {
1760 ret = mbedtls_snprintf(p, n, "\nCertificate is uninitialised!\n");
1761 MBEDTLS_X509_SAFE_SNPRINTF;
1762
1763 return (int) (size - n);
1764 }
1765
1766 ret = mbedtls_snprintf(p, n, "%scert. version : %d\n",
1767 prefix, crt->version);
1768 MBEDTLS_X509_SAFE_SNPRINTF;
1769 ret = mbedtls_snprintf(p, n, "%sserial number : ",
1770 prefix);
1771 MBEDTLS_X509_SAFE_SNPRINTF;
1772
1773 ret = mbedtls_x509_serial_gets(p, n, &crt->serial);
1774 MBEDTLS_X509_SAFE_SNPRINTF;
1775
1776 ret = mbedtls_snprintf(p, n, "\n%sissuer name : ", prefix);
1777 MBEDTLS_X509_SAFE_SNPRINTF;
1778 ret = mbedtls_x509_dn_gets(p, n, &crt->issuer);
1779 MBEDTLS_X509_SAFE_SNPRINTF;
1780
1781 ret = mbedtls_snprintf(p, n, "\n%ssubject name : ", prefix);
1782 MBEDTLS_X509_SAFE_SNPRINTF;
1783 ret = mbedtls_x509_dn_gets(p, n, &crt->subject);
1784 MBEDTLS_X509_SAFE_SNPRINTF;
1785
1786 ret = mbedtls_snprintf(p, n, "\n%sissued on : " \
1787 "%04d-%02d-%02d %02d:%02d:%02d", prefix,
1788 crt->valid_from.year, crt->valid_from.mon,
1789 crt->valid_from.day, crt->valid_from.hour,
1790 crt->valid_from.min, crt->valid_from.sec);
1791 MBEDTLS_X509_SAFE_SNPRINTF;
1792
1793 ret = mbedtls_snprintf(p, n, "\n%sexpires on : " \
1794 "%04d-%02d-%02d %02d:%02d:%02d", prefix,
1795 crt->valid_to.year, crt->valid_to.mon,
1796 crt->valid_to.day, crt->valid_to.hour,
1797 crt->valid_to.min, crt->valid_to.sec);
1798 MBEDTLS_X509_SAFE_SNPRINTF;
1799
1800 ret = mbedtls_snprintf(p, n, "\n%ssigned using : ", prefix);
1801 MBEDTLS_X509_SAFE_SNPRINTF;
1802
1803 ret = mbedtls_x509_sig_alg_gets(p, n, &crt->sig_oid, crt->sig_pk,
1804 crt->sig_md, crt->sig_opts);
1805 MBEDTLS_X509_SAFE_SNPRINTF;
1806
1807 /* Key size */
1808 if ((ret = mbedtls_x509_key_size_helper(key_size_str, BEFORE_COLON,
1809 mbedtls_pk_get_name(&crt->pk))) != 0) {
1810 return ret;
1811 }
1812
1813 ret = mbedtls_snprintf(p, n, "\n%s%-" BC "s: %d bits", prefix, key_size_str,
1814 (int) mbedtls_pk_get_bitlen(&crt->pk));
1815 MBEDTLS_X509_SAFE_SNPRINTF;
1816
1817 /*
1818 * Optional extensions
1819 */
1820
1821 if (crt->ext_types & MBEDTLS_X509_EXT_BASIC_CONSTRAINTS) {
1822 ret = mbedtls_snprintf(p, n, "\n%sbasic constraints : CA=%s", prefix,
1823 crt->ca_istrue ? "true" : "false");
1824 MBEDTLS_X509_SAFE_SNPRINTF;
1825
1826 if (crt->max_pathlen > 0) {
1827 ret = mbedtls_snprintf(p, n, ", max_pathlen=%d", crt->max_pathlen - 1);
1828 MBEDTLS_X509_SAFE_SNPRINTF;
1829 }
1830 }
1831
1832 if (crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME) {
1833 ret = mbedtls_snprintf(p, n, "\n%ssubject alt name :", prefix);
1834 MBEDTLS_X509_SAFE_SNPRINTF;
1835
1836 if ((ret = mbedtls_x509_info_subject_alt_name(&p, &n,
1837 &crt->subject_alt_names,
1838 prefix)) != 0) {
1839 return ret;
1840 }
1841 }
1842
1843 if (crt->ext_types & MBEDTLS_X509_EXT_NS_CERT_TYPE) {
1844 ret = mbedtls_snprintf(p, n, "\n%scert. type : ", prefix);
1845 MBEDTLS_X509_SAFE_SNPRINTF;
1846
1847 if ((ret = mbedtls_x509_info_cert_type(&p, &n, crt->ns_cert_type)) != 0) {
1848 return ret;
1849 }
1850 }
1851
1852 if (crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE) {
1853 ret = mbedtls_snprintf(p, n, "\n%skey usage : ", prefix);
1854 MBEDTLS_X509_SAFE_SNPRINTF;
1855
1856 if ((ret = mbedtls_x509_info_key_usage(&p, &n, crt->key_usage)) != 0) {
1857 return ret;
1858 }
1859 }
1860
1861 if (crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE) {
1862 ret = mbedtls_snprintf(p, n, "\n%sext key usage : ", prefix);
1863 MBEDTLS_X509_SAFE_SNPRINTF;
1864
1865 if ((ret = x509_info_ext_key_usage(&p, &n,
1866 &crt->ext_key_usage)) != 0) {
1867 return ret;
1868 }
1869 }
1870
1871 if (crt->ext_types & MBEDTLS_OID_X509_EXT_CERTIFICATE_POLICIES) {
1872 ret = mbedtls_snprintf(p, n, "\n%scertificate policies : ", prefix);
1873 MBEDTLS_X509_SAFE_SNPRINTF;
1874
1875 if ((ret = x509_info_cert_policies(&p, &n,
1876 &crt->certificate_policies)) != 0) {
1877 return ret;
1878 }
1879 }
1880
1881 ret = mbedtls_snprintf(p, n, "\n");
1882 MBEDTLS_X509_SAFE_SNPRINTF;
1883
1884 return (int) (size - n);
1885 }
1886
1887 struct x509_crt_verify_string {
1888 int code;
1889 const char *string;
1890 };
1891
1892 #define X509_CRT_ERROR_INFO(err, err_str, info) { err, info },
1893 static const struct x509_crt_verify_string x509_crt_verify_strings[] = {
1894 MBEDTLS_X509_CRT_ERROR_INFO_LIST
1895 { 0, NULL }
1896 };
1897 #undef X509_CRT_ERROR_INFO
1898
mbedtls_x509_crt_verify_info(char * buf,size_t size,const char * prefix,uint32_t flags)1899 int mbedtls_x509_crt_verify_info(char *buf, size_t size, const char *prefix,
1900 uint32_t flags)
1901 {
1902 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1903 const struct x509_crt_verify_string *cur;
1904 char *p = buf;
1905 size_t n = size;
1906
1907 for (cur = x509_crt_verify_strings; cur->string != NULL; cur++) {
1908 if ((flags & cur->code) == 0) {
1909 continue;
1910 }
1911
1912 ret = mbedtls_snprintf(p, n, "%s%s\n", prefix, cur->string);
1913 MBEDTLS_X509_SAFE_SNPRINTF;
1914 flags ^= cur->code;
1915 }
1916
1917 if (flags != 0) {
1918 ret = mbedtls_snprintf(p, n, "%sUnknown reason "
1919 "(this should not happen)\n", prefix);
1920 MBEDTLS_X509_SAFE_SNPRINTF;
1921 }
1922
1923 return (int) (size - n);
1924 }
1925 #endif /* MBEDTLS_X509_REMOVE_INFO */
1926
mbedtls_x509_crt_check_key_usage(const mbedtls_x509_crt * crt,unsigned int usage)1927 int mbedtls_x509_crt_check_key_usage(const mbedtls_x509_crt *crt,
1928 unsigned int usage)
1929 {
1930 unsigned int usage_must, usage_may;
1931 unsigned int may_mask = MBEDTLS_X509_KU_ENCIPHER_ONLY
1932 | MBEDTLS_X509_KU_DECIPHER_ONLY;
1933
1934 if ((crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE) == 0) {
1935 return 0;
1936 }
1937
1938 usage_must = usage & ~may_mask;
1939
1940 if (((crt->key_usage & ~may_mask) & usage_must) != usage_must) {
1941 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1942 }
1943
1944 usage_may = usage & may_mask;
1945
1946 if (((crt->key_usage & may_mask) | usage_may) != usage_may) {
1947 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1948 }
1949
1950 return 0;
1951 }
1952
mbedtls_x509_crt_check_extended_key_usage(const mbedtls_x509_crt * crt,const char * usage_oid,size_t usage_len)1953 int mbedtls_x509_crt_check_extended_key_usage(const mbedtls_x509_crt *crt,
1954 const char *usage_oid,
1955 size_t usage_len)
1956 {
1957 const mbedtls_x509_sequence *cur;
1958
1959 /* Extension is not mandatory, absent means no restriction */
1960 if ((crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE) == 0) {
1961 return 0;
1962 }
1963
1964 /*
1965 * Look for the requested usage (or wildcard ANY) in our list
1966 */
1967 for (cur = &crt->ext_key_usage; cur != NULL; cur = cur->next) {
1968 const mbedtls_x509_buf *cur_oid = &cur->buf;
1969
1970 if (cur_oid->len == usage_len &&
1971 memcmp(cur_oid->p, usage_oid, usage_len) == 0) {
1972 return 0;
1973 }
1974
1975 if (MBEDTLS_OID_CMP(MBEDTLS_OID_ANY_EXTENDED_KEY_USAGE, cur_oid) == 0) {
1976 return 0;
1977 }
1978 }
1979
1980 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1981 }
1982
1983 #if defined(MBEDTLS_X509_CRL_PARSE_C)
1984 /*
1985 * Return 1 if the certificate is revoked, or 0 otherwise.
1986 */
mbedtls_x509_crt_is_revoked(const mbedtls_x509_crt * crt,const mbedtls_x509_crl * crl)1987 int mbedtls_x509_crt_is_revoked(const mbedtls_x509_crt *crt, const mbedtls_x509_crl *crl)
1988 {
1989 const mbedtls_x509_crl_entry *cur = &crl->entry;
1990
1991 while (cur != NULL && cur->serial.len != 0) {
1992 if (crt->serial.len == cur->serial.len &&
1993 memcmp(crt->serial.p, cur->serial.p, crt->serial.len) == 0) {
1994 return 1;
1995 }
1996
1997 cur = cur->next;
1998 }
1999
2000 return 0;
2001 }
2002
2003 /*
2004 * Check that the given certificate is not revoked according to the CRL.
2005 * Skip validation if no CRL for the given CA is present.
2006 */
x509_crt_verifycrl(mbedtls_x509_crt * crt,mbedtls_x509_crt * ca,mbedtls_x509_crl * crl_list,const mbedtls_x509_crt_profile * profile,const mbedtls_x509_time * now)2007 static int x509_crt_verifycrl(mbedtls_x509_crt *crt, mbedtls_x509_crt *ca,
2008 mbedtls_x509_crl *crl_list,
2009 const mbedtls_x509_crt_profile *profile,
2010 const mbedtls_x509_time *now)
2011 {
2012 int flags = 0;
2013 unsigned char hash[MBEDTLS_MD_MAX_SIZE];
2014 #if defined(MBEDTLS_USE_PSA_CRYPTO)
2015 psa_algorithm_t psa_algorithm;
2016 #else
2017 const mbedtls_md_info_t *md_info;
2018 #endif /* MBEDTLS_USE_PSA_CRYPTO */
2019 size_t hash_length;
2020
2021 if (ca == NULL) {
2022 return flags;
2023 }
2024
2025 while (crl_list != NULL) {
2026 if (crl_list->version == 0 ||
2027 x509_name_cmp(&crl_list->issuer, &ca->subject) != 0) {
2028 crl_list = crl_list->next;
2029 continue;
2030 }
2031
2032 /*
2033 * Check if the CA is configured to sign CRLs
2034 */
2035 if (mbedtls_x509_crt_check_key_usage(ca,
2036 MBEDTLS_X509_KU_CRL_SIGN) != 0) {
2037 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
2038 break;
2039 }
2040
2041 /*
2042 * Check if CRL is correctly signed by the trusted CA
2043 */
2044 if (x509_profile_check_md_alg(profile, crl_list->sig_md) != 0) {
2045 flags |= MBEDTLS_X509_BADCRL_BAD_MD;
2046 }
2047
2048 if (x509_profile_check_pk_alg(profile, crl_list->sig_pk) != 0) {
2049 flags |= MBEDTLS_X509_BADCRL_BAD_PK;
2050 }
2051
2052 #if defined(MBEDTLS_USE_PSA_CRYPTO)
2053 psa_algorithm = mbedtls_md_psa_alg_from_type(crl_list->sig_md);
2054 if (psa_hash_compute(psa_algorithm,
2055 crl_list->tbs.p,
2056 crl_list->tbs.len,
2057 hash,
2058 sizeof(hash),
2059 &hash_length) != PSA_SUCCESS) {
2060 /* Note: this can't happen except after an internal error */
2061 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
2062 break;
2063 }
2064 #else
2065 md_info = mbedtls_md_info_from_type(crl_list->sig_md);
2066 hash_length = mbedtls_md_get_size(md_info);
2067 if (mbedtls_md(md_info,
2068 crl_list->tbs.p,
2069 crl_list->tbs.len,
2070 hash) != 0) {
2071 /* Note: this can't happen except after an internal error */
2072 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
2073 break;
2074 }
2075 #endif /* MBEDTLS_USE_PSA_CRYPTO */
2076
2077 if (x509_profile_check_key(profile, &ca->pk) != 0) {
2078 flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
2079 }
2080
2081 if (mbedtls_pk_verify_ext(crl_list->sig_pk, crl_list->sig_opts, &ca->pk,
2082 crl_list->sig_md, hash, hash_length,
2083 crl_list->sig.p, crl_list->sig.len) != 0) {
2084 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
2085 break;
2086 }
2087
2088 #if defined(MBEDTLS_HAVE_TIME_DATE)
2089 /*
2090 * Check for validity of CRL (Do not drop out)
2091 */
2092 if (mbedtls_x509_time_cmp(&crl_list->next_update, now) < 0) {
2093 flags |= MBEDTLS_X509_BADCRL_EXPIRED;
2094 }
2095
2096 if (mbedtls_x509_time_cmp(&crl_list->this_update, now) > 0) {
2097 flags |= MBEDTLS_X509_BADCRL_FUTURE;
2098 }
2099 #else
2100 ((void) now);
2101 #endif
2102
2103 /*
2104 * Check if certificate is revoked
2105 */
2106 if (mbedtls_x509_crt_is_revoked(crt, crl_list)) {
2107 flags |= MBEDTLS_X509_BADCERT_REVOKED;
2108 break;
2109 }
2110
2111 crl_list = crl_list->next;
2112 }
2113
2114 return flags;
2115 }
2116 #endif /* MBEDTLS_X509_CRL_PARSE_C */
2117
2118 /*
2119 * Check the signature of a certificate by its parent
2120 */
x509_crt_check_signature(const mbedtls_x509_crt * child,mbedtls_x509_crt * parent,mbedtls_x509_crt_restart_ctx * rs_ctx)2121 static int x509_crt_check_signature(const mbedtls_x509_crt *child,
2122 mbedtls_x509_crt *parent,
2123 mbedtls_x509_crt_restart_ctx *rs_ctx)
2124 {
2125 size_t hash_len;
2126 unsigned char hash[MBEDTLS_MD_MAX_SIZE];
2127 #if !defined(MBEDTLS_USE_PSA_CRYPTO)
2128 const mbedtls_md_info_t *md_info;
2129 md_info = mbedtls_md_info_from_type(child->sig_md);
2130 hash_len = mbedtls_md_get_size(md_info);
2131
2132 /* Note: hash errors can happen only after an internal error */
2133 if (mbedtls_md(md_info, child->tbs.p, child->tbs.len, hash) != 0) {
2134 return -1;
2135 }
2136 #else
2137 psa_algorithm_t hash_alg = mbedtls_md_psa_alg_from_type(child->sig_md);
2138 psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
2139
2140 status = psa_hash_compute(hash_alg,
2141 child->tbs.p,
2142 child->tbs.len,
2143 hash,
2144 sizeof(hash),
2145 &hash_len);
2146 if (status != PSA_SUCCESS) {
2147 return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED;
2148 }
2149
2150 #endif /* MBEDTLS_USE_PSA_CRYPTO */
2151 /* Skip expensive computation on obvious mismatch */
2152 if (!mbedtls_pk_can_do(&parent->pk, child->sig_pk)) {
2153 return -1;
2154 }
2155
2156 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2157 if (rs_ctx != NULL && child->sig_pk == MBEDTLS_PK_ECDSA) {
2158 return mbedtls_pk_verify_restartable(&parent->pk,
2159 child->sig_md, hash, hash_len,
2160 child->sig.p, child->sig.len, &rs_ctx->pk);
2161 }
2162 #else
2163 (void) rs_ctx;
2164 #endif
2165
2166 return mbedtls_pk_verify_ext(child->sig_pk, child->sig_opts, &parent->pk,
2167 child->sig_md, hash, hash_len,
2168 child->sig.p, child->sig.len);
2169 }
2170
2171 /*
2172 * Check if 'parent' is a suitable parent (signing CA) for 'child'.
2173 * Return 0 if yes, -1 if not.
2174 *
2175 * top means parent is a locally-trusted certificate
2176 */
x509_crt_check_parent(const mbedtls_x509_crt * child,const mbedtls_x509_crt * parent,int top)2177 static int x509_crt_check_parent(const mbedtls_x509_crt *child,
2178 const mbedtls_x509_crt *parent,
2179 int top)
2180 {
2181 int need_ca_bit;
2182
2183 /* Parent must be the issuer */
2184 if (x509_name_cmp(&child->issuer, &parent->subject) != 0) {
2185 return -1;
2186 }
2187
2188 /* Parent must have the basicConstraints CA bit set as a general rule */
2189 need_ca_bit = 1;
2190
2191 /* Exception: v1/v2 certificates that are locally trusted. */
2192 if (top && parent->version < 3) {
2193 need_ca_bit = 0;
2194 }
2195
2196 if (need_ca_bit && !parent->ca_istrue) {
2197 return -1;
2198 }
2199
2200 if (need_ca_bit &&
2201 mbedtls_x509_crt_check_key_usage(parent, MBEDTLS_X509_KU_KEY_CERT_SIGN) != 0) {
2202 return -1;
2203 }
2204
2205 return 0;
2206 }
2207
2208 /*
2209 * Find a suitable parent for child in candidates, or return NULL.
2210 *
2211 * Here suitable is defined as:
2212 * 1. subject name matches child's issuer
2213 * 2. if necessary, the CA bit is set and key usage allows signing certs
2214 * 3. for trusted roots, the signature is correct
2215 * (for intermediates, the signature is checked and the result reported)
2216 * 4. pathlen constraints are satisfied
2217 *
2218 * If there's a suitable candidate which is also time-valid, return the first
2219 * such. Otherwise, return the first suitable candidate (or NULL if there is
2220 * none).
2221 *
2222 * The rationale for this rule is that someone could have a list of trusted
2223 * roots with two versions on the same root with different validity periods.
2224 * (At least one user reported having such a list and wanted it to just work.)
2225 * The reason we don't just require time-validity is that generally there is
2226 * only one version, and if it's expired we want the flags to state that
2227 * rather than NOT_TRUSTED, as would be the case if we required it here.
2228 *
2229 * The rationale for rule 3 (signature for trusted roots) is that users might
2230 * have two versions of the same CA with different keys in their list, and the
2231 * way we select the correct one is by checking the signature (as we don't
2232 * rely on key identifier extensions). (This is one way users might choose to
2233 * handle key rollover, another relies on self-issued certs, see [SIRO].)
2234 *
2235 * Arguments:
2236 * - [in] child: certificate for which we're looking for a parent
2237 * - [in] candidates: chained list of potential parents
2238 * - [out] r_parent: parent found (or NULL)
2239 * - [out] r_signature_is_good: 1 if child signature by parent is valid, or 0
2240 * - [in] top: 1 if candidates consists of trusted roots, ie we're at the top
2241 * of the chain, 0 otherwise
2242 * - [in] path_cnt: number of intermediates seen so far
2243 * - [in] self_cnt: number of self-signed intermediates seen so far
2244 * (will never be greater than path_cnt)
2245 * - [in-out] rs_ctx: context for restarting operations
2246 *
2247 * Return value:
2248 * - 0 on success
2249 * - MBEDTLS_ERR_ECP_IN_PROGRESS otherwise
2250 */
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,const mbedtls_x509_time * now)2251 static int x509_crt_find_parent_in(
2252 mbedtls_x509_crt *child,
2253 mbedtls_x509_crt *candidates,
2254 mbedtls_x509_crt **r_parent,
2255 int *r_signature_is_good,
2256 int top,
2257 unsigned path_cnt,
2258 unsigned self_cnt,
2259 mbedtls_x509_crt_restart_ctx *rs_ctx,
2260 const mbedtls_x509_time *now)
2261 {
2262 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
2263 mbedtls_x509_crt *parent, *fallback_parent;
2264 int signature_is_good = 0, fallback_signature_is_good;
2265
2266 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2267 /* did we have something in progress? */
2268 if (rs_ctx != NULL && rs_ctx->parent != NULL) {
2269 /* restore saved state */
2270 parent = rs_ctx->parent;
2271 fallback_parent = rs_ctx->fallback_parent;
2272 fallback_signature_is_good = rs_ctx->fallback_signature_is_good;
2273
2274 /* clear saved state */
2275 rs_ctx->parent = NULL;
2276 rs_ctx->fallback_parent = NULL;
2277 rs_ctx->fallback_signature_is_good = 0;
2278
2279 /* resume where we left */
2280 goto check_signature;
2281 }
2282 #endif
2283
2284 fallback_parent = NULL;
2285 fallback_signature_is_good = 0;
2286
2287 for (parent = candidates; parent != NULL; parent = parent->next) {
2288 /* basic parenting skills (name, CA bit, key usage) */
2289 if (x509_crt_check_parent(child, parent, top) != 0) {
2290 continue;
2291 }
2292
2293 /* +1 because stored max_pathlen is 1 higher that the actual value */
2294 if (parent->max_pathlen > 0 &&
2295 (size_t) parent->max_pathlen < 1 + path_cnt - self_cnt) {
2296 continue;
2297 }
2298
2299 /* Signature */
2300 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2301 check_signature:
2302 #endif
2303 ret = x509_crt_check_signature(child, parent, rs_ctx);
2304
2305 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2306 if (rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS) {
2307 /* save state */
2308 rs_ctx->parent = parent;
2309 rs_ctx->fallback_parent = fallback_parent;
2310 rs_ctx->fallback_signature_is_good = fallback_signature_is_good;
2311
2312 return ret;
2313 }
2314 #else
2315 (void) ret;
2316 #endif
2317
2318 signature_is_good = ret == 0;
2319 if (top && !signature_is_good) {
2320 continue;
2321 }
2322
2323 #if defined(MBEDTLS_HAVE_TIME_DATE)
2324 /* optional time check */
2325 if (mbedtls_x509_time_cmp(&parent->valid_to, now) < 0 || /* past */
2326 mbedtls_x509_time_cmp(&parent->valid_from, now) > 0) { /* future */
2327 if (fallback_parent == NULL) {
2328 fallback_parent = parent;
2329 fallback_signature_is_good = signature_is_good;
2330 }
2331
2332 continue;
2333 }
2334 #else
2335 ((void) now);
2336 #endif
2337
2338 *r_parent = parent;
2339 *r_signature_is_good = signature_is_good;
2340
2341 break;
2342 }
2343
2344 if (parent == NULL) {
2345 *r_parent = fallback_parent;
2346 *r_signature_is_good = fallback_signature_is_good;
2347 }
2348
2349 return 0;
2350 }
2351
2352 /*
2353 * Find a parent in trusted CAs or the provided chain, or return NULL.
2354 *
2355 * Searches in trusted CAs first, and return the first suitable parent found
2356 * (see find_parent_in() for definition of suitable).
2357 *
2358 * Arguments:
2359 * - [in] child: certificate for which we're looking for a parent, followed
2360 * by a chain of possible intermediates
2361 * - [in] trust_ca: list of locally trusted certificates
2362 * - [out] parent: parent found (or NULL)
2363 * - [out] parent_is_trusted: 1 if returned `parent` is trusted, or 0
2364 * - [out] signature_is_good: 1 if child signature by parent is valid, or 0
2365 * - [in] path_cnt: number of links in the chain so far (EE -> ... -> child)
2366 * - [in] self_cnt: number of self-signed certs in the chain so far
2367 * (will always be no greater than path_cnt)
2368 * - [in-out] rs_ctx: context for restarting operations
2369 *
2370 * Return value:
2371 * - 0 on success
2372 * - MBEDTLS_ERR_ECP_IN_PROGRESS otherwise
2373 */
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,const mbedtls_x509_time * now)2374 static int x509_crt_find_parent(
2375 mbedtls_x509_crt *child,
2376 mbedtls_x509_crt *trust_ca,
2377 mbedtls_x509_crt **parent,
2378 int *parent_is_trusted,
2379 int *signature_is_good,
2380 unsigned path_cnt,
2381 unsigned self_cnt,
2382 mbedtls_x509_crt_restart_ctx *rs_ctx,
2383 const mbedtls_x509_time *now)
2384 {
2385 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
2386 mbedtls_x509_crt *search_list;
2387
2388 *parent_is_trusted = 1;
2389
2390 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2391 /* restore then clear saved state if we have some stored */
2392 if (rs_ctx != NULL && rs_ctx->parent_is_trusted != -1) {
2393 *parent_is_trusted = rs_ctx->parent_is_trusted;
2394 rs_ctx->parent_is_trusted = -1;
2395 }
2396 #endif
2397
2398 while (1) {
2399 search_list = *parent_is_trusted ? trust_ca : child->next;
2400
2401 ret = x509_crt_find_parent_in(child, search_list,
2402 parent, signature_is_good,
2403 *parent_is_trusted,
2404 path_cnt, self_cnt, rs_ctx, now);
2405
2406 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2407 if (rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS) {
2408 /* save state */
2409 rs_ctx->parent_is_trusted = *parent_is_trusted;
2410 return ret;
2411 }
2412 #else
2413 (void) ret;
2414 #endif
2415
2416 /* stop here if found or already in second iteration */
2417 if (*parent != NULL || *parent_is_trusted == 0) {
2418 break;
2419 }
2420
2421 /* prepare second iteration */
2422 *parent_is_trusted = 0;
2423 }
2424
2425 /* extra precaution against mistakes in the caller */
2426 if (*parent == NULL) {
2427 *parent_is_trusted = 0;
2428 *signature_is_good = 0;
2429 }
2430
2431 return 0;
2432 }
2433
2434 /*
2435 * Check if an end-entity certificate is locally trusted
2436 *
2437 * Currently we require such certificates to be self-signed (actually only
2438 * check for self-issued as self-signatures are not checked)
2439 */
x509_crt_check_ee_locally_trusted(mbedtls_x509_crt * crt,mbedtls_x509_crt * trust_ca)2440 static int x509_crt_check_ee_locally_trusted(
2441 mbedtls_x509_crt *crt,
2442 mbedtls_x509_crt *trust_ca)
2443 {
2444 mbedtls_x509_crt *cur;
2445
2446 /* must be self-issued */
2447 if (x509_name_cmp(&crt->issuer, &crt->subject) != 0) {
2448 return -1;
2449 }
2450
2451 /* look for an exact match with trusted cert */
2452 for (cur = trust_ca; cur != NULL; cur = cur->next) {
2453 if (crt->raw.len == cur->raw.len &&
2454 memcmp(crt->raw.p, cur->raw.p, crt->raw.len) == 0) {
2455 return 0;
2456 }
2457 }
2458
2459 /* too bad */
2460 return -1;
2461 }
2462
2463 /*
2464 * Build and verify a certificate chain
2465 *
2466 * Given a peer-provided list of certificates EE, C1, ..., Cn and
2467 * a list of trusted certs R1, ... Rp, try to build and verify a chain
2468 * EE, Ci1, ... Ciq [, Rj]
2469 * such that every cert in the chain is a child of the next one,
2470 * jumping to a trusted root as early as possible.
2471 *
2472 * Verify that chain and return it with flags for all issues found.
2473 *
2474 * Special cases:
2475 * - EE == Rj -> return a one-element list containing it
2476 * - EE, Ci1, ..., Ciq cannot be continued with a trusted root
2477 * -> return that chain with NOT_TRUSTED set on Ciq
2478 *
2479 * Tests for (aspects of) this function should include at least:
2480 * - trusted EE
2481 * - EE -> trusted root
2482 * - EE -> intermediate CA -> trusted root
2483 * - if relevant: EE untrusted
2484 * - if relevant: EE -> intermediate, untrusted
2485 * with the aspect under test checked at each relevant level (EE, int, root).
2486 * For some aspects longer chains are required, but usually length 2 is
2487 * enough (but length 1 is not in general).
2488 *
2489 * Arguments:
2490 * - [in] crt: the cert list EE, C1, ..., Cn
2491 * - [in] trust_ca: the trusted list R1, ..., Rp
2492 * - [in] ca_crl, profile: as in verify_with_profile()
2493 * - [out] ver_chain: the built and verified chain
2494 * Only valid when return value is 0, may contain garbage otherwise!
2495 * Restart note: need not be the same when calling again to resume.
2496 * - [in-out] rs_ctx: context for restarting operations
2497 *
2498 * Return value:
2499 * - non-zero if the chain could not be fully built and examined
2500 * - 0 is the chain was successfully built and examined,
2501 * even if it was found to be invalid
2502 */
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)2503 static int x509_crt_verify_chain(
2504 mbedtls_x509_crt *crt,
2505 mbedtls_x509_crt *trust_ca,
2506 mbedtls_x509_crl *ca_crl,
2507 mbedtls_x509_crt_ca_cb_t f_ca_cb,
2508 void *p_ca_cb,
2509 const mbedtls_x509_crt_profile *profile,
2510 mbedtls_x509_crt_verify_chain *ver_chain,
2511 mbedtls_x509_crt_restart_ctx *rs_ctx)
2512 {
2513 /* Don't initialize any of those variables here, so that the compiler can
2514 * catch potential issues with jumping ahead when restarting */
2515 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
2516 uint32_t *flags;
2517 mbedtls_x509_crt_verify_chain_item *cur;
2518 mbedtls_x509_crt *child;
2519 mbedtls_x509_crt *parent;
2520 int parent_is_trusted;
2521 int child_is_trusted;
2522 int signature_is_good;
2523 unsigned self_cnt;
2524 mbedtls_x509_crt *cur_trust_ca = NULL;
2525 mbedtls_x509_time now;
2526
2527 #if defined(MBEDTLS_HAVE_TIME_DATE)
2528 if (mbedtls_x509_time_gmtime(mbedtls_time(NULL), &now) != 0) {
2529 return MBEDTLS_ERR_X509_FATAL_ERROR;
2530 }
2531 #endif
2532
2533 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2534 /* resume if we had an operation in progress */
2535 if (rs_ctx != NULL && rs_ctx->in_progress == x509_crt_rs_find_parent) {
2536 /* restore saved state */
2537 *ver_chain = rs_ctx->ver_chain; /* struct copy */
2538 self_cnt = rs_ctx->self_cnt;
2539
2540 /* restore derived state */
2541 cur = &ver_chain->items[ver_chain->len - 1];
2542 child = cur->crt;
2543 flags = &cur->flags;
2544
2545 goto find_parent;
2546 }
2547 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
2548
2549 child = crt;
2550 self_cnt = 0;
2551 parent_is_trusted = 0;
2552 child_is_trusted = 0;
2553
2554 while (1) {
2555 /* Add certificate to the verification chain */
2556 cur = &ver_chain->items[ver_chain->len];
2557 cur->crt = child;
2558 cur->flags = 0;
2559 ver_chain->len++;
2560 flags = &cur->flags;
2561
2562 #if defined(MBEDTLS_HAVE_TIME_DATE)
2563 /* Check time-validity (all certificates) */
2564 if (mbedtls_x509_time_cmp(&child->valid_to, &now) < 0) {
2565 *flags |= MBEDTLS_X509_BADCERT_EXPIRED;
2566 }
2567
2568 if (mbedtls_x509_time_cmp(&child->valid_from, &now) > 0) {
2569 *flags |= MBEDTLS_X509_BADCERT_FUTURE;
2570 }
2571 #endif
2572
2573 /* Stop here for trusted roots (but not for trusted EE certs) */
2574 if (child_is_trusted) {
2575 return 0;
2576 }
2577
2578 /* Check signature algorithm: MD & PK algs */
2579 if (x509_profile_check_md_alg(profile, child->sig_md) != 0) {
2580 *flags |= MBEDTLS_X509_BADCERT_BAD_MD;
2581 }
2582
2583 if (x509_profile_check_pk_alg(profile, child->sig_pk) != 0) {
2584 *flags |= MBEDTLS_X509_BADCERT_BAD_PK;
2585 }
2586
2587 /* Special case: EE certs that are locally trusted */
2588 if (ver_chain->len == 1 &&
2589 x509_crt_check_ee_locally_trusted(child, trust_ca) == 0) {
2590 return 0;
2591 }
2592
2593 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2594 find_parent:
2595 #endif
2596
2597 /* Obtain list of potential trusted signers from CA callback,
2598 * or use statically provided list. */
2599 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
2600 if (f_ca_cb != NULL) {
2601 mbedtls_x509_crt_free(ver_chain->trust_ca_cb_result);
2602 mbedtls_free(ver_chain->trust_ca_cb_result);
2603 ver_chain->trust_ca_cb_result = NULL;
2604
2605 ret = f_ca_cb(p_ca_cb, child, &ver_chain->trust_ca_cb_result);
2606 if (ret != 0) {
2607 return MBEDTLS_ERR_X509_FATAL_ERROR;
2608 }
2609
2610 cur_trust_ca = ver_chain->trust_ca_cb_result;
2611 } else
2612 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
2613 {
2614 ((void) f_ca_cb);
2615 ((void) p_ca_cb);
2616 cur_trust_ca = trust_ca;
2617 }
2618
2619 /* Look for a parent in trusted CAs or up the chain */
2620 ret = x509_crt_find_parent(child, cur_trust_ca, &parent,
2621 &parent_is_trusted, &signature_is_good,
2622 ver_chain->len - 1, self_cnt, rs_ctx,
2623 &now);
2624
2625 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2626 if (rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS) {
2627 /* save state */
2628 rs_ctx->in_progress = x509_crt_rs_find_parent;
2629 rs_ctx->self_cnt = self_cnt;
2630 rs_ctx->ver_chain = *ver_chain; /* struct copy */
2631
2632 return ret;
2633 }
2634 #else
2635 (void) ret;
2636 #endif
2637
2638 /* No parent? We're done here */
2639 if (parent == NULL) {
2640 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
2641 return 0;
2642 }
2643
2644 /* Count intermediate self-issued (not necessarily self-signed) certs.
2645 * These can occur with some strategies for key rollover, see [SIRO],
2646 * and should be excluded from max_pathlen checks. */
2647 if (ver_chain->len != 1 &&
2648 x509_name_cmp(&child->issuer, &child->subject) == 0) {
2649 self_cnt++;
2650 }
2651
2652 /* path_cnt is 0 for the first intermediate CA,
2653 * and if parent is trusted it's not an intermediate CA */
2654 if (!parent_is_trusted &&
2655 ver_chain->len > MBEDTLS_X509_MAX_INTERMEDIATE_CA) {
2656 /* return immediately to avoid overflow the chain array */
2657 return MBEDTLS_ERR_X509_FATAL_ERROR;
2658 }
2659
2660 /* signature was checked while searching parent */
2661 if (!signature_is_good) {
2662 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
2663 }
2664
2665 /* check size of signing key */
2666 if (x509_profile_check_key(profile, &parent->pk) != 0) {
2667 *flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
2668 }
2669
2670 #if defined(MBEDTLS_X509_CRL_PARSE_C)
2671 /* Check trusted CA's CRL for the given crt */
2672 *flags |= x509_crt_verifycrl(child, parent, ca_crl, profile, &now);
2673 #else
2674 (void) ca_crl;
2675 #endif
2676
2677 /* prepare for next iteration */
2678 child = parent;
2679 parent = NULL;
2680 child_is_trusted = parent_is_trusted;
2681 signature_is_good = 0;
2682 }
2683 }
2684
2685 #ifdef _WIN32
2686 #ifdef _MSC_VER
2687 #pragma comment(lib, "ws2_32.lib")
2688 #include <winsock2.h>
2689 #include <ws2tcpip.h>
2690 #elif (defined(__MINGW32__) || defined(__MINGW64__)) && _WIN32_WINNT >= 0x0600
2691 #include <winsock2.h>
2692 #include <ws2tcpip.h>
2693 #else
2694 /* inet_pton() is not supported, fallback to software version */
2695 #define MBEDTLS_TEST_SW_INET_PTON
2696 #endif
2697 #elif defined(__sun)
2698 /* Solaris requires -lsocket -lnsl for inet_pton() */
2699 #elif defined(__has_include)
2700 #if __has_include(<sys/socket.h>)
2701 #include <sys/socket.h>
2702 #endif
2703 #if __has_include(<arpa/inet.h>)
2704 #include <arpa/inet.h>
2705 #endif
2706 #endif
2707
2708 /* Use whether or not AF_INET6 is defined to indicate whether or not to use
2709 * the platform inet_pton() or a local implementation (below). The local
2710 * implementation may be used even in cases where the platform provides
2711 * inet_pton(), e.g. when there are different includes required and/or the
2712 * platform implementation requires dependencies on additional libraries.
2713 * Specifically, Windows requires custom includes and additional link
2714 * dependencies, and Solaris requires additional link dependencies.
2715 * Also, as a coarse heuristic, use the local implementation if the compiler
2716 * does not support __has_include(), or if the definition of AF_INET6 is not
2717 * provided by headers included (or not) via __has_include() above.
2718 * MBEDTLS_TEST_SW_INET_PTON is a bypass define to force testing of this code //no-check-names
2719 * despite having a platform that has inet_pton. */
2720 #if !defined(AF_INET6) || defined(MBEDTLS_TEST_SW_INET_PTON) //no-check-names
2721 /* Definition located further below to possibly reduce compiler inlining */
2722 static int x509_inet_pton_ipv4(const char *src, void *dst);
2723
2724 #define li_cton(c, n) \
2725 (((n) = (c) - '0') <= 9 || (((n) = ((c)&0xdf) - 'A') <= 5 ? ((n) += 10) : 0))
2726
x509_inet_pton_ipv6(const char * src,void * dst)2727 static int x509_inet_pton_ipv6(const char *src, void *dst)
2728 {
2729 const unsigned char *p = (const unsigned char *) src;
2730 int nonzero_groups = 0, num_digits, zero_group_start = -1;
2731 uint16_t addr[8];
2732 do {
2733 /* note: allows excess leading 0's, e.g. 1:0002:3:... */
2734 uint16_t group = num_digits = 0;
2735 for (uint8_t digit; num_digits < 4; num_digits++) {
2736 if (li_cton(*p, digit) == 0) {
2737 break;
2738 }
2739 group = (group << 4) | digit;
2740 p++;
2741 }
2742 if (num_digits != 0) {
2743 MBEDTLS_PUT_UINT16_BE(group, addr, nonzero_groups);
2744 nonzero_groups++;
2745 if (*p == '\0') {
2746 break;
2747 } else if (*p == '.') {
2748 /* Don't accept IPv4 too early or late */
2749 if ((nonzero_groups == 0 && zero_group_start == -1) ||
2750 nonzero_groups >= 7) {
2751 break;
2752 }
2753
2754 /* Walk back to prior ':', then parse as IPv4-mapped */
2755 int steps = 4;
2756 do {
2757 p--;
2758 steps--;
2759 } while (*p != ':' && steps > 0);
2760
2761 if (*p != ':') {
2762 break;
2763 }
2764 p++;
2765 nonzero_groups--;
2766 if (x509_inet_pton_ipv4((const char *) p,
2767 addr + nonzero_groups) != 0) {
2768 break;
2769 }
2770
2771 nonzero_groups += 2;
2772 p = (const unsigned char *) "";
2773 break;
2774 } else if (*p != ':') {
2775 return -1;
2776 }
2777 } else {
2778 /* Don't accept a second zero group or an invalid delimiter */
2779 if (zero_group_start != -1 || *p != ':') {
2780 return -1;
2781 }
2782 zero_group_start = nonzero_groups;
2783
2784 /* Accept a zero group at start, but it has to be a double colon */
2785 if (zero_group_start == 0 && *++p != ':') {
2786 return -1;
2787 }
2788
2789 if (p[1] == '\0') {
2790 ++p;
2791 break;
2792 }
2793 }
2794 ++p;
2795 } while (nonzero_groups < 8);
2796
2797 if (*p != '\0') {
2798 return -1;
2799 }
2800
2801 if (zero_group_start != -1) {
2802 if (nonzero_groups > 6) {
2803 return -1;
2804 }
2805 int zero_groups = 8 - nonzero_groups;
2806 int groups_after_zero = nonzero_groups - zero_group_start;
2807
2808 /* Move the non-zero part to after the zeroes */
2809 if (groups_after_zero) {
2810 memmove(addr + zero_group_start + zero_groups,
2811 addr + zero_group_start,
2812 groups_after_zero * sizeof(*addr));
2813 }
2814 memset(addr + zero_group_start, 0, zero_groups * sizeof(*addr));
2815 } else {
2816 if (nonzero_groups != 8) {
2817 return -1;
2818 }
2819 }
2820 memcpy(dst, addr, sizeof(addr));
2821 return 0;
2822 }
2823
x509_inet_pton_ipv4(const char * src,void * dst)2824 static int x509_inet_pton_ipv4(const char *src, void *dst)
2825 {
2826 const unsigned char *p = (const unsigned char *) src;
2827 uint8_t *res = (uint8_t *) dst;
2828 uint8_t digit, num_digits = 0;
2829 uint8_t num_octets = 0;
2830 uint16_t octet;
2831
2832 do {
2833 octet = num_digits = 0;
2834 do {
2835 digit = *p - '0';
2836 if (digit > 9) {
2837 break;
2838 }
2839
2840 /* Don't allow leading zeroes. These might mean octal format,
2841 * which this implementation does not support. */
2842 if (octet == 0 && num_digits > 0) {
2843 return -1;
2844 }
2845
2846 octet = octet * 10 + digit;
2847 num_digits++;
2848 p++;
2849 } while (num_digits < 3);
2850
2851 if (octet >= 256 || num_digits > 3 || num_digits == 0) {
2852 return -1;
2853 }
2854 *res++ = (uint8_t) octet;
2855 num_octets++;
2856 } while (num_octets < 4 && *p++ == '.');
2857 return num_octets == 4 && *p == '\0' ? 0 : -1;
2858 }
2859
2860 #else
2861
x509_inet_pton_ipv6(const char * src,void * dst)2862 static int x509_inet_pton_ipv6(const char *src, void *dst)
2863 {
2864 return inet_pton(AF_INET6, src, dst) == 1 ? 0 : -1;
2865 }
2866
x509_inet_pton_ipv4(const char * src,void * dst)2867 static int x509_inet_pton_ipv4(const char *src, void *dst)
2868 {
2869 return inet_pton(AF_INET, src, dst) == 1 ? 0 : -1;
2870 }
2871
2872 #endif /* !AF_INET6 || MBEDTLS_TEST_SW_INET_PTON */ //no-check-names
2873
mbedtls_x509_crt_parse_cn_inet_pton(const char * cn,void * dst)2874 size_t mbedtls_x509_crt_parse_cn_inet_pton(const char *cn, void *dst)
2875 {
2876 return strchr(cn, ':') == NULL
2877 ? x509_inet_pton_ipv4(cn, dst) == 0 ? 4 : 0
2878 : x509_inet_pton_ipv6(cn, dst) == 0 ? 16 : 0;
2879 }
2880
2881 /*
2882 * Check for CN match
2883 */
x509_crt_check_cn(const mbedtls_x509_buf * name,const char * cn,size_t cn_len)2884 static int x509_crt_check_cn(const mbedtls_x509_buf *name,
2885 const char *cn, size_t cn_len)
2886 {
2887 /* try exact match */
2888 if (name->len == cn_len &&
2889 x509_memcasecmp(cn, name->p, cn_len) == 0) {
2890 return 0;
2891 }
2892
2893 /* try wildcard match */
2894 if (x509_check_wildcard(cn, name) == 0) {
2895 return 0;
2896 }
2897
2898 return -1;
2899 }
2900
x509_crt_check_san_ip(const mbedtls_x509_sequence * san,const char * cn,size_t cn_len)2901 static int x509_crt_check_san_ip(const mbedtls_x509_sequence *san,
2902 const char *cn, size_t cn_len)
2903 {
2904 uint32_t ip[4];
2905 cn_len = mbedtls_x509_crt_parse_cn_inet_pton(cn, ip);
2906 if (cn_len == 0) {
2907 return -1;
2908 }
2909
2910 for (const mbedtls_x509_sequence *cur = san; cur != NULL; cur = cur->next) {
2911 const unsigned char san_type = (unsigned char) cur->buf.tag &
2912 MBEDTLS_ASN1_TAG_VALUE_MASK;
2913 if (san_type == MBEDTLS_X509_SAN_IP_ADDRESS &&
2914 cur->buf.len == cn_len && memcmp(cur->buf.p, ip, cn_len) == 0) {
2915 return 0;
2916 }
2917 }
2918
2919 return -1;
2920 }
2921
x509_crt_check_san_uri(const mbedtls_x509_sequence * san,const char * cn,size_t cn_len)2922 static int x509_crt_check_san_uri(const mbedtls_x509_sequence *san,
2923 const char *cn, size_t cn_len)
2924 {
2925 for (const mbedtls_x509_sequence *cur = san; cur != NULL; cur = cur->next) {
2926 const unsigned char san_type = (unsigned char) cur->buf.tag &
2927 MBEDTLS_ASN1_TAG_VALUE_MASK;
2928 if (san_type == MBEDTLS_X509_SAN_UNIFORM_RESOURCE_IDENTIFIER &&
2929 cur->buf.len == cn_len && memcmp(cur->buf.p, cn, cn_len) == 0) {
2930 return 0;
2931 }
2932 }
2933
2934 return -1;
2935 }
2936
2937 /*
2938 * Check for SAN match, see RFC 5280 Section 4.2.1.6
2939 */
x509_crt_check_san(const mbedtls_x509_sequence * san,const char * cn,size_t cn_len)2940 static int x509_crt_check_san(const mbedtls_x509_sequence *san,
2941 const char *cn, size_t cn_len)
2942 {
2943 int san_ip = 0;
2944 int san_uri = 0;
2945 /* Prioritize DNS name over other subtypes due to popularity */
2946 for (const mbedtls_x509_sequence *cur = san; cur != NULL; cur = cur->next) {
2947 switch ((unsigned char) cur->buf.tag & MBEDTLS_ASN1_TAG_VALUE_MASK) {
2948 case MBEDTLS_X509_SAN_DNS_NAME:
2949 if (x509_crt_check_cn(&cur->buf, cn, cn_len) == 0) {
2950 return 0;
2951 }
2952 break;
2953 case MBEDTLS_X509_SAN_IP_ADDRESS:
2954 san_ip = 1;
2955 break;
2956 case MBEDTLS_X509_SAN_UNIFORM_RESOURCE_IDENTIFIER:
2957 san_uri = 1;
2958 break;
2959 /* (We may handle other types here later.) */
2960 default: /* Unrecognized type */
2961 break;
2962 }
2963 }
2964 if (san_ip) {
2965 if (x509_crt_check_san_ip(san, cn, cn_len) == 0) {
2966 return 0;
2967 }
2968 }
2969 if (san_uri) {
2970 if (x509_crt_check_san_uri(san, cn, cn_len) == 0) {
2971 return 0;
2972 }
2973 }
2974
2975 return -1;
2976 }
2977
2978 /*
2979 * Verify the requested CN - only call this if cn is not NULL!
2980 */
x509_crt_verify_name(const mbedtls_x509_crt * crt,const char * cn,uint32_t * flags)2981 static void x509_crt_verify_name(const mbedtls_x509_crt *crt,
2982 const char *cn,
2983 uint32_t *flags)
2984 {
2985 const mbedtls_x509_name *name;
2986 size_t cn_len = strlen(cn);
2987
2988 if (crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME) {
2989 if (x509_crt_check_san(&crt->subject_alt_names, cn, cn_len) == 0) {
2990 return;
2991 }
2992 } else {
2993 for (name = &crt->subject; name != NULL; name = name->next) {
2994 if (MBEDTLS_OID_CMP(MBEDTLS_OID_AT_CN, &name->oid) == 0 &&
2995 x509_crt_check_cn(&name->val, cn, cn_len) == 0) {
2996 return;
2997 }
2998 }
2999
3000 }
3001
3002 *flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH;
3003 }
3004
3005 /*
3006 * Merge the flags for all certs in the chain, after calling callback
3007 */
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)3008 static int x509_crt_merge_flags_with_cb(
3009 uint32_t *flags,
3010 const mbedtls_x509_crt_verify_chain *ver_chain,
3011 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3012 void *p_vrfy)
3013 {
3014 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
3015 unsigned i;
3016 uint32_t cur_flags;
3017 const mbedtls_x509_crt_verify_chain_item *cur;
3018
3019 for (i = ver_chain->len; i != 0; --i) {
3020 cur = &ver_chain->items[i-1];
3021 cur_flags = cur->flags;
3022
3023 if (NULL != f_vrfy) {
3024 if ((ret = f_vrfy(p_vrfy, cur->crt, (int) i-1, &cur_flags)) != 0) {
3025 return ret;
3026 }
3027 }
3028
3029 *flags |= cur_flags;
3030 }
3031
3032 return 0;
3033 }
3034
3035 /*
3036 * Verify the certificate validity, with profile, restartable version
3037 *
3038 * This function:
3039 * - checks the requested CN (if any)
3040 * - checks the type and size of the EE cert's key,
3041 * as that isn't done as part of chain building/verification currently
3042 * - builds and verifies the chain
3043 * - then calls the callback and merges the flags
3044 *
3045 * The parameters pairs `trust_ca`, `ca_crl` and `f_ca_cb`, `p_ca_cb`
3046 * are mutually exclusive: If `f_ca_cb != NULL`, it will be used by the
3047 * verification routine to search for trusted signers, and CRLs will
3048 * be disabled. Otherwise, `trust_ca` will be used as the static list
3049 * of trusted signers, and `ca_crl` will be use as the static list
3050 * of CRLs.
3051 */
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)3052 static int x509_crt_verify_restartable_ca_cb(mbedtls_x509_crt *crt,
3053 mbedtls_x509_crt *trust_ca,
3054 mbedtls_x509_crl *ca_crl,
3055 mbedtls_x509_crt_ca_cb_t f_ca_cb,
3056 void *p_ca_cb,
3057 const mbedtls_x509_crt_profile *profile,
3058 const char *cn, uint32_t *flags,
3059 int (*f_vrfy)(void *,
3060 mbedtls_x509_crt *,
3061 int,
3062 uint32_t *),
3063 void *p_vrfy,
3064 mbedtls_x509_crt_restart_ctx *rs_ctx)
3065 {
3066 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
3067 mbedtls_pk_type_t pk_type;
3068 mbedtls_x509_crt_verify_chain ver_chain;
3069 uint32_t ee_flags;
3070
3071 *flags = 0;
3072 ee_flags = 0;
3073 x509_crt_verify_chain_reset(&ver_chain);
3074
3075 if (profile == NULL) {
3076 ret = MBEDTLS_ERR_X509_BAD_INPUT_DATA;
3077 goto exit;
3078 }
3079
3080 /* check name if requested */
3081 if (cn != NULL) {
3082 x509_crt_verify_name(crt, cn, &ee_flags);
3083 }
3084
3085 /* Check the type and size of the key */
3086 pk_type = mbedtls_pk_get_type(&crt->pk);
3087
3088 if (x509_profile_check_pk_alg(profile, pk_type) != 0) {
3089 ee_flags |= MBEDTLS_X509_BADCERT_BAD_PK;
3090 }
3091
3092 if (x509_profile_check_key(profile, &crt->pk) != 0) {
3093 ee_flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
3094 }
3095
3096 /* Check the chain */
3097 ret = x509_crt_verify_chain(crt, trust_ca, ca_crl,
3098 f_ca_cb, p_ca_cb, profile,
3099 &ver_chain, rs_ctx);
3100
3101 if (ret != 0) {
3102 goto exit;
3103 }
3104
3105 /* Merge end-entity flags */
3106 ver_chain.items[0].flags |= ee_flags;
3107
3108 /* Build final flags, calling callback on the way if any */
3109 ret = x509_crt_merge_flags_with_cb(flags, &ver_chain, f_vrfy, p_vrfy);
3110
3111 exit:
3112
3113 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
3114 mbedtls_x509_crt_free(ver_chain.trust_ca_cb_result);
3115 mbedtls_free(ver_chain.trust_ca_cb_result);
3116 ver_chain.trust_ca_cb_result = NULL;
3117 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
3118
3119 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
3120 if (rs_ctx != NULL && ret != MBEDTLS_ERR_ECP_IN_PROGRESS) {
3121 mbedtls_x509_crt_restart_free(rs_ctx);
3122 }
3123 #endif
3124
3125 /* prevent misuse of the vrfy callback - VERIFY_FAILED would be ignored by
3126 * the SSL module for authmode optional, but non-zero return from the
3127 * callback means a fatal error so it shouldn't be ignored */
3128 if (ret == MBEDTLS_ERR_X509_CERT_VERIFY_FAILED) {
3129 ret = MBEDTLS_ERR_X509_FATAL_ERROR;
3130 }
3131
3132 if (ret != 0) {
3133 *flags = (uint32_t) -1;
3134 return ret;
3135 }
3136
3137 if (*flags != 0) {
3138 return MBEDTLS_ERR_X509_CERT_VERIFY_FAILED;
3139 }
3140
3141 return 0;
3142 }
3143
3144
3145 /*
3146 * Verify the certificate validity (default profile, not restartable)
3147 */
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)3148 int mbedtls_x509_crt_verify(mbedtls_x509_crt *crt,
3149 mbedtls_x509_crt *trust_ca,
3150 mbedtls_x509_crl *ca_crl,
3151 const char *cn, uint32_t *flags,
3152 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3153 void *p_vrfy)
3154 {
3155 return x509_crt_verify_restartable_ca_cb(crt, trust_ca, ca_crl,
3156 NULL, NULL,
3157 &mbedtls_x509_crt_profile_default,
3158 cn, flags,
3159 f_vrfy, p_vrfy, NULL);
3160 }
3161
3162 /*
3163 * Verify the certificate validity (user-chosen profile, not restartable)
3164 */
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)3165 int mbedtls_x509_crt_verify_with_profile(mbedtls_x509_crt *crt,
3166 mbedtls_x509_crt *trust_ca,
3167 mbedtls_x509_crl *ca_crl,
3168 const mbedtls_x509_crt_profile *profile,
3169 const char *cn, uint32_t *flags,
3170 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3171 void *p_vrfy)
3172 {
3173 return x509_crt_verify_restartable_ca_cb(crt, trust_ca, ca_crl,
3174 NULL, NULL,
3175 profile, cn, flags,
3176 f_vrfy, p_vrfy, NULL);
3177 }
3178
3179 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
3180 /*
3181 * Verify the certificate validity (user-chosen profile, CA callback,
3182 * not restartable).
3183 */
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)3184 int mbedtls_x509_crt_verify_with_ca_cb(mbedtls_x509_crt *crt,
3185 mbedtls_x509_crt_ca_cb_t f_ca_cb,
3186 void *p_ca_cb,
3187 const mbedtls_x509_crt_profile *profile,
3188 const char *cn, uint32_t *flags,
3189 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3190 void *p_vrfy)
3191 {
3192 return x509_crt_verify_restartable_ca_cb(crt, NULL, NULL,
3193 f_ca_cb, p_ca_cb,
3194 profile, cn, flags,
3195 f_vrfy, p_vrfy, NULL);
3196 }
3197 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
3198
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)3199 int mbedtls_x509_crt_verify_restartable(mbedtls_x509_crt *crt,
3200 mbedtls_x509_crt *trust_ca,
3201 mbedtls_x509_crl *ca_crl,
3202 const mbedtls_x509_crt_profile *profile,
3203 const char *cn, uint32_t *flags,
3204 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3205 void *p_vrfy,
3206 mbedtls_x509_crt_restart_ctx *rs_ctx)
3207 {
3208 return x509_crt_verify_restartable_ca_cb(crt, trust_ca, ca_crl,
3209 NULL, NULL,
3210 profile, cn, flags,
3211 f_vrfy, p_vrfy, rs_ctx);
3212 }
3213
3214
3215 /*
3216 * Initialize a certificate chain
3217 */
mbedtls_x509_crt_init(mbedtls_x509_crt * crt)3218 void mbedtls_x509_crt_init(mbedtls_x509_crt *crt)
3219 {
3220 memset(crt, 0, sizeof(mbedtls_x509_crt));
3221 }
3222
3223 /*
3224 * Unallocate all certificate data
3225 */
mbedtls_x509_crt_free(mbedtls_x509_crt * crt)3226 void mbedtls_x509_crt_free(mbedtls_x509_crt *crt)
3227 {
3228 mbedtls_x509_crt *cert_cur = crt;
3229 mbedtls_x509_crt *cert_prv;
3230
3231 while (cert_cur != NULL) {
3232 mbedtls_pk_free(&cert_cur->pk);
3233
3234 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
3235 mbedtls_free(cert_cur->sig_opts);
3236 #endif
3237
3238 mbedtls_asn1_free_named_data_list_shallow(cert_cur->issuer.next);
3239 mbedtls_asn1_free_named_data_list_shallow(cert_cur->subject.next);
3240 mbedtls_asn1_sequence_free(cert_cur->ext_key_usage.next);
3241 mbedtls_asn1_sequence_free(cert_cur->subject_alt_names.next);
3242 mbedtls_asn1_sequence_free(cert_cur->certificate_policies.next);
3243 mbedtls_asn1_sequence_free(cert_cur->authority_key_id.authorityCertIssuer.next);
3244
3245 if (cert_cur->raw.p != NULL && cert_cur->own_buffer) {
3246 mbedtls_zeroize_and_free(cert_cur->raw.p, cert_cur->raw.len);
3247 }
3248
3249 cert_prv = cert_cur;
3250 cert_cur = cert_cur->next;
3251
3252 mbedtls_platform_zeroize(cert_prv, sizeof(mbedtls_x509_crt));
3253 if (cert_prv != crt) {
3254 mbedtls_free(cert_prv);
3255 }
3256 }
3257 }
3258
3259 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
3260 /*
3261 * Initialize a restart context
3262 */
mbedtls_x509_crt_restart_init(mbedtls_x509_crt_restart_ctx * ctx)3263 void mbedtls_x509_crt_restart_init(mbedtls_x509_crt_restart_ctx *ctx)
3264 {
3265 mbedtls_pk_restart_init(&ctx->pk);
3266
3267 ctx->parent = NULL;
3268 ctx->fallback_parent = NULL;
3269 ctx->fallback_signature_is_good = 0;
3270
3271 ctx->parent_is_trusted = -1;
3272
3273 ctx->in_progress = x509_crt_rs_none;
3274 ctx->self_cnt = 0;
3275 x509_crt_verify_chain_reset(&ctx->ver_chain);
3276 }
3277
3278 /*
3279 * Free the components of a restart context
3280 */
mbedtls_x509_crt_restart_free(mbedtls_x509_crt_restart_ctx * ctx)3281 void mbedtls_x509_crt_restart_free(mbedtls_x509_crt_restart_ctx *ctx)
3282 {
3283 if (ctx == NULL) {
3284 return;
3285 }
3286
3287 mbedtls_pk_restart_free(&ctx->pk);
3288 mbedtls_x509_crt_restart_init(ctx);
3289 }
3290 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
3291
3292 #endif /* MBEDTLS_X509_CRT_PARSE_C */
3293
