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 "x509_internal.h"
26 #include "mbedtls/error.h"
27 #include "mbedtls/oid.h"
28 #include "mbedtls/platform_util.h"
29
30 #include <string.h>
31
32 #if defined(MBEDTLS_PEM_PARSE_C)
33 #include "mbedtls/pem.h"
34 #endif
35
36 #if defined(MBEDTLS_USE_PSA_CRYPTO)
37 #include "psa/crypto.h"
38 #include "psa_util_internal.h"
39 #include "mbedtls/psa_util.h"
40 #endif /* MBEDTLS_USE_PSA_CRYPTO */
41 #include "pk_internal.h"
42
43 #include "mbedtls/platform.h"
44
45 #if defined(MBEDTLS_THREADING_C)
46 #include "mbedtls/threading.h"
47 #endif
48
49 #if defined(MBEDTLS_HAVE_TIME)
50 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
51 #define WIN32_LEAN_AND_MEAN
52 #include <windows.h>
53 #else
54 #include <time.h>
55 #endif
56 #endif
57
58 #if defined(MBEDTLS_FS_IO)
59 #include <stdio.h>
60 #if !defined(_WIN32) || defined(EFIX64) || defined(EFI32)
61 #include <sys/types.h>
62 #include <sys/stat.h>
63 #if defined(__MBED__)
64 #include <platform/mbed_retarget.h>
65 #else
66 #include <dirent.h>
67 #endif /* __MBED__ */
68 #include <errno.h>
69 #endif /* !_WIN32 || EFIX64 || EFI32 */
70 #endif
71
72 /*
73 * Item in a verification chain: cert and flags for it
74 */
75 typedef struct {
76 mbedtls_x509_crt *crt;
77 uint32_t flags;
78 } x509_crt_verify_chain_item;
79
80 /*
81 * Max size of verification chain: end-entity + intermediates + trusted root
82 */
83 #define X509_MAX_VERIFY_CHAIN_SIZE (MBEDTLS_X509_MAX_INTERMEDIATE_CA + 2)
84
85 /* Default profile. Do not remove items unless there are serious security
86 * concerns. */
87 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_default =
88 {
89 /* Hashes from SHA-256 and above. Note that this selection
90 * should be aligned with ssl_preset_default_hashes in ssl_tls.c. */
91 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA256) |
92 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA384) |
93 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA512),
94 0xFFFFFFF, /* Any PK alg */
95 #if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
96 /* Curves at or above 128-bit security level. Note that this selection
97 * should be aligned with ssl_preset_default_curves in ssl_tls.c. */
98 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP256R1) |
99 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP384R1) |
100 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP521R1) |
101 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_BP256R1) |
102 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_BP384R1) |
103 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_BP512R1) |
104 0,
105 #else /* MBEDTLS_PK_HAVE_ECC_KEYS */
106 0,
107 #endif /* MBEDTLS_PK_HAVE_ECC_KEYS */
108 2048,
109 };
110
111 /* Next-generation profile. Currently identical to the default, but may
112 * be tightened at any time. */
113 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_next =
114 {
115 /* Hashes from SHA-256 and above. */
116 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA256) |
117 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA384) |
118 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA512),
119 0xFFFFFFF, /* Any PK alg */
120 #if defined(MBEDTLS_ECP_C)
121 /* Curves at or above 128-bit security level. */
122 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP256R1) |
123 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP384R1) |
124 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP521R1) |
125 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_BP256R1) |
126 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_BP384R1) |
127 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_BP512R1) |
128 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP256K1),
129 #else
130 0,
131 #endif
132 2048,
133 };
134
135 /*
136 * NSA Suite B Profile
137 */
138 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_suiteb =
139 {
140 /* Only SHA-256 and 384 */
141 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA256) |
142 MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA384),
143 /* Only ECDSA */
144 MBEDTLS_X509_ID_FLAG(MBEDTLS_PK_ECDSA) |
145 MBEDTLS_X509_ID_FLAG(MBEDTLS_PK_ECKEY),
146 #if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
147 /* Only NIST P-256 and P-384 */
148 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP256R1) |
149 MBEDTLS_X509_ID_FLAG(MBEDTLS_ECP_DP_SECP384R1),
150 #else /* MBEDTLS_PK_HAVE_ECC_KEYS */
151 0,
152 #endif /* MBEDTLS_PK_HAVE_ECC_KEYS */
153 0,
154 };
155
156 /*
157 * Empty / all-forbidden profile
158 */
159 const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_none =
160 {
161 0,
162 0,
163 0,
164 (uint32_t) -1,
165 };
166
167 /*
168 * Check md_alg against profile
169 * Return 0 if md_alg is acceptable for this profile, -1 otherwise
170 */
x509_profile_check_md_alg(const mbedtls_x509_crt_profile * profile,mbedtls_md_type_t md_alg)171 static int x509_profile_check_md_alg(const mbedtls_x509_crt_profile *profile,
172 mbedtls_md_type_t md_alg)
173 {
174 if (md_alg == MBEDTLS_MD_NONE) {
175 return -1;
176 }
177
178 if ((profile->allowed_mds & MBEDTLS_X509_ID_FLAG(md_alg)) != 0) {
179 return 0;
180 }
181
182 return -1;
183 }
184
185 /*
186 * Check pk_alg against profile
187 * Return 0 if pk_alg is acceptable for this profile, -1 otherwise
188 */
x509_profile_check_pk_alg(const mbedtls_x509_crt_profile * profile,mbedtls_pk_type_t pk_alg)189 static int x509_profile_check_pk_alg(const mbedtls_x509_crt_profile *profile,
190 mbedtls_pk_type_t pk_alg)
191 {
192 if (pk_alg == MBEDTLS_PK_NONE) {
193 return -1;
194 }
195
196 if ((profile->allowed_pks & MBEDTLS_X509_ID_FLAG(pk_alg)) != 0) {
197 return 0;
198 }
199
200 return -1;
201 }
202
203 /*
204 * Check key against profile
205 * Return 0 if pk is acceptable for this profile, -1 otherwise
206 */
x509_profile_check_key(const mbedtls_x509_crt_profile * profile,const mbedtls_pk_context * pk)207 static int x509_profile_check_key(const mbedtls_x509_crt_profile *profile,
208 const mbedtls_pk_context *pk)
209 {
210 const mbedtls_pk_type_t pk_alg = mbedtls_pk_get_type(pk);
211
212 #if defined(MBEDTLS_RSA_C)
213 if (pk_alg == MBEDTLS_PK_RSA || pk_alg == MBEDTLS_PK_RSASSA_PSS) {
214 if (mbedtls_pk_get_bitlen(pk) >= profile->rsa_min_bitlen) {
215 return 0;
216 }
217
218 return -1;
219 }
220 #endif /* MBEDTLS_RSA_C */
221
222 #if defined(MBEDTLS_PK_HAVE_ECC_KEYS)
223 if (pk_alg == MBEDTLS_PK_ECDSA ||
224 pk_alg == MBEDTLS_PK_ECKEY ||
225 pk_alg == MBEDTLS_PK_ECKEY_DH) {
226 const mbedtls_ecp_group_id gid = mbedtls_pk_get_ec_group_id(pk);
227
228 if (gid == MBEDTLS_ECP_DP_NONE) {
229 return -1;
230 }
231
232 if ((profile->allowed_curves & MBEDTLS_X509_ID_FLAG(gid)) != 0) {
233 return 0;
234 }
235
236 return -1;
237 }
238 #endif /* MBEDTLS_PK_HAVE_ECC_KEYS */
239
240 return -1;
241 }
242
243 /*
244 * Like memcmp, but case-insensitive and always returns -1 if different
245 */
x509_memcasecmp(const void * s1,const void * s2,size_t len)246 static int x509_memcasecmp(const void *s1, const void *s2, size_t len)
247 {
248 size_t i;
249 unsigned char diff;
250 const unsigned char *n1 = s1, *n2 = s2;
251
252 for (i = 0; i < len; i++) {
253 diff = n1[i] ^ n2[i];
254
255 if (diff == 0) {
256 continue;
257 }
258
259 if (diff == 32 &&
260 ((n1[i] >= 'a' && n1[i] <= 'z') ||
261 (n1[i] >= 'A' && n1[i] <= 'Z'))) {
262 continue;
263 }
264
265 return -1;
266 }
267
268 return 0;
269 }
270
271 /*
272 * Return 0 if name matches wildcard, -1 otherwise
273 */
x509_check_wildcard(const char * cn,const mbedtls_x509_buf * name)274 static int x509_check_wildcard(const char *cn, const mbedtls_x509_buf *name)
275 {
276 size_t i;
277 size_t cn_idx = 0, cn_len = strlen(cn);
278
279 /* We can't have a match if there is no wildcard to match */
280 if (name->len < 3 || name->p[0] != '*' || name->p[1] != '.') {
281 return -1;
282 }
283
284 for (i = 0; i < cn_len; ++i) {
285 if (cn[i] == '.') {
286 cn_idx = i;
287 break;
288 }
289 }
290
291 if (cn_idx == 0) {
292 return -1;
293 }
294
295 if (cn_len - cn_idx == name->len - 1 &&
296 x509_memcasecmp(name->p + 1, cn + cn_idx, name->len - 1) == 0) {
297 return 0;
298 }
299
300 return -1;
301 }
302
303 /*
304 * Compare two X.509 strings, case-insensitive, and allowing for some encoding
305 * variations (but not all).
306 *
307 * Return 0 if equal, -1 otherwise.
308 */
x509_string_cmp(const mbedtls_x509_buf * a,const mbedtls_x509_buf * b)309 static int x509_string_cmp(const mbedtls_x509_buf *a, const mbedtls_x509_buf *b)
310 {
311 if (a->tag == b->tag &&
312 a->len == b->len &&
313 memcmp(a->p, b->p, b->len) == 0) {
314 return 0;
315 }
316
317 if ((a->tag == MBEDTLS_ASN1_UTF8_STRING || a->tag == MBEDTLS_ASN1_PRINTABLE_STRING) &&
318 (b->tag == MBEDTLS_ASN1_UTF8_STRING || b->tag == MBEDTLS_ASN1_PRINTABLE_STRING) &&
319 a->len == b->len &&
320 x509_memcasecmp(a->p, b->p, b->len) == 0) {
321 return 0;
322 }
323
324 return -1;
325 }
326
327 /*
328 * Compare two X.509 Names (aka rdnSequence).
329 *
330 * See RFC 5280 section 7.1, though we don't implement the whole algorithm:
331 * we sometimes return unequal when the full algorithm would return equal,
332 * but never the other way. (In particular, we don't do Unicode normalisation
333 * or space folding.)
334 *
335 * Return 0 if equal, -1 otherwise.
336 */
x509_name_cmp(const mbedtls_x509_name * a,const mbedtls_x509_name * b)337 static int x509_name_cmp(const mbedtls_x509_name *a, const mbedtls_x509_name *b)
338 {
339 /* Avoid recursion, it might not be optimised by the compiler */
340 while (a != NULL || b != NULL) {
341 if (a == NULL || b == NULL) {
342 return -1;
343 }
344
345 /* type */
346 if (a->oid.tag != b->oid.tag ||
347 a->oid.len != b->oid.len ||
348 memcmp(a->oid.p, b->oid.p, b->oid.len) != 0) {
349 return -1;
350 }
351
352 /* value */
353 if (x509_string_cmp(&a->val, &b->val) != 0) {
354 return -1;
355 }
356
357 /* structure of the list of sets */
358 if (a->next_merged != b->next_merged) {
359 return -1;
360 }
361
362 a = a->next;
363 b = b->next;
364 }
365
366 /* a == NULL == b */
367 return 0;
368 }
369
370 /*
371 * Reset (init or clear) a verify_chain
372 */
x509_crt_verify_chain_reset(mbedtls_x509_crt_verify_chain * ver_chain)373 static void x509_crt_verify_chain_reset(
374 mbedtls_x509_crt_verify_chain *ver_chain)
375 {
376 size_t i;
377
378 for (i = 0; i < MBEDTLS_X509_MAX_VERIFY_CHAIN_SIZE; i++) {
379 ver_chain->items[i].crt = NULL;
380 ver_chain->items[i].flags = (uint32_t) -1;
381 }
382
383 ver_chain->len = 0;
384
385 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
386 ver_chain->trust_ca_cb_result = NULL;
387 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
388 }
389
390 /*
391 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
392 */
x509_get_version(unsigned char ** p,const unsigned char * end,int * ver)393 static int x509_get_version(unsigned char **p,
394 const unsigned char *end,
395 int *ver)
396 {
397 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
398 size_t len;
399
400 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
401 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED |
402 0)) != 0) {
403 if (ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
404 *ver = 0;
405 return 0;
406 }
407
408 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
409 }
410
411 end = *p + len;
412
413 if ((ret = mbedtls_asn1_get_int(p, end, ver)) != 0) {
414 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_VERSION, ret);
415 }
416
417 if (*p != end) {
418 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_VERSION,
419 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
420 }
421
422 return 0;
423 }
424
425 /*
426 * Validity ::= SEQUENCE {
427 * notBefore Time,
428 * notAfter Time }
429 */
x509_get_dates(unsigned char ** p,const unsigned char * end,mbedtls_x509_time * from,mbedtls_x509_time * to)430 static int x509_get_dates(unsigned char **p,
431 const unsigned char *end,
432 mbedtls_x509_time *from,
433 mbedtls_x509_time *to)
434 {
435 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
436 size_t len;
437
438 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
439 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
440 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_DATE, ret);
441 }
442
443 end = *p + len;
444
445 if ((ret = mbedtls_x509_get_time(p, end, from)) != 0) {
446 return ret;
447 }
448
449 if ((ret = mbedtls_x509_get_time(p, end, to)) != 0) {
450 return ret;
451 }
452
453 if (*p != end) {
454 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_DATE,
455 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
456 }
457
458 return 0;
459 }
460
461 /*
462 * X.509 v2/v3 unique identifier (not parsed)
463 */
x509_get_uid(unsigned char ** p,const unsigned char * end,mbedtls_x509_buf * uid,int n)464 static int x509_get_uid(unsigned char **p,
465 const unsigned char *end,
466 mbedtls_x509_buf *uid, int n)
467 {
468 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
469
470 if (*p == end) {
471 return 0;
472 }
473
474 uid->tag = **p;
475
476 if ((ret = mbedtls_asn1_get_tag(p, end, &uid->len,
477 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED |
478 n)) != 0) {
479 if (ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
480 return 0;
481 }
482
483 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
484 }
485
486 uid->p = *p;
487 *p += uid->len;
488
489 return 0;
490 }
491
x509_get_basic_constraints(unsigned char ** p,const unsigned char * end,int * ca_istrue,int * max_pathlen)492 static int x509_get_basic_constraints(unsigned char **p,
493 const unsigned char *end,
494 int *ca_istrue,
495 int *max_pathlen)
496 {
497 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
498 size_t len;
499
500 /*
501 * BasicConstraints ::= SEQUENCE {
502 * cA BOOLEAN DEFAULT FALSE,
503 * pathLenConstraint INTEGER (0..MAX) OPTIONAL }
504 */
505 *ca_istrue = 0; /* DEFAULT FALSE */
506 *max_pathlen = 0; /* endless */
507
508 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
509 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
510 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
511 }
512
513 if (*p == end) {
514 return 0;
515 }
516
517 if ((ret = mbedtls_asn1_get_bool(p, end, ca_istrue)) != 0) {
518 if (ret == MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
519 ret = mbedtls_asn1_get_int(p, end, ca_istrue);
520 }
521
522 if (ret != 0) {
523 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
524 }
525
526 if (*ca_istrue != 0) {
527 *ca_istrue = 1;
528 }
529 }
530
531 if (*p == end) {
532 return 0;
533 }
534
535 if ((ret = mbedtls_asn1_get_int(p, end, max_pathlen)) != 0) {
536 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
537 }
538
539 if (*p != end) {
540 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
541 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
542 }
543
544 /* Do not accept max_pathlen equal to INT_MAX to avoid a signed integer
545 * overflow, which is an undefined behavior. */
546 if (*max_pathlen == INT_MAX) {
547 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
548 MBEDTLS_ERR_ASN1_INVALID_LENGTH);
549 }
550
551 (*max_pathlen)++;
552
553 return 0;
554 }
555
556 /*
557 * ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId
558 *
559 * KeyPurposeId ::= OBJECT IDENTIFIER
560 */
x509_get_ext_key_usage(unsigned char ** p,const unsigned char * end,mbedtls_x509_sequence * ext_key_usage)561 static int x509_get_ext_key_usage(unsigned char **p,
562 const unsigned char *end,
563 mbedtls_x509_sequence *ext_key_usage)
564 {
565 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
566
567 if ((ret = mbedtls_asn1_get_sequence_of(p, end, ext_key_usage, MBEDTLS_ASN1_OID)) != 0) {
568 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
569 }
570
571 /* Sequence length must be >= 1 */
572 if (ext_key_usage->buf.p == NULL) {
573 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
574 MBEDTLS_ERR_ASN1_INVALID_LENGTH);
575 }
576
577 return 0;
578 }
579
580 /*
581 * SubjectKeyIdentifier ::= KeyIdentifier
582 *
583 * KeyIdentifier ::= OCTET STRING
584 */
x509_get_subject_key_id(unsigned char ** p,const unsigned char * end,mbedtls_x509_buf * subject_key_id)585 static int x509_get_subject_key_id(unsigned char **p,
586 const unsigned char *end,
587 mbedtls_x509_buf *subject_key_id)
588 {
589 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
590 size_t len = 0u;
591
592 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
593 MBEDTLS_ASN1_OCTET_STRING)) != 0) {
594 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
595 }
596
597 subject_key_id->len = len;
598 subject_key_id->tag = MBEDTLS_ASN1_OCTET_STRING;
599 subject_key_id->p = *p;
600 *p += len;
601
602 if (*p != end) {
603 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
604 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
605 }
606
607 return 0;
608 }
609
610 /*
611 * AuthorityKeyIdentifier ::= SEQUENCE {
612 * keyIdentifier [0] KeyIdentifier OPTIONAL,
613 * authorityCertIssuer [1] GeneralNames OPTIONAL,
614 * authorityCertSerialNumber [2] CertificateSerialNumber OPTIONAL }
615 *
616 * KeyIdentifier ::= OCTET STRING
617 */
x509_get_authority_key_id(unsigned char ** p,unsigned char * end,mbedtls_x509_authority * authority_key_id)618 static int x509_get_authority_key_id(unsigned char **p,
619 unsigned char *end,
620 mbedtls_x509_authority *authority_key_id)
621 {
622 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
623 size_t len = 0u;
624
625 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
626 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
627 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
628 }
629
630 if (*p + len != end) {
631 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
632 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
633 }
634
635 ret = mbedtls_asn1_get_tag(p, end, &len,
636 MBEDTLS_ASN1_CONTEXT_SPECIFIC);
637
638 /* KeyIdentifier is an OPTIONAL field */
639 if (ret == 0) {
640 authority_key_id->keyIdentifier.len = len;
641 authority_key_id->keyIdentifier.p = *p;
642 /* Setting tag of the keyIdentfier intentionally to 0x04.
643 * Although the .keyIdentfier field is CONTEXT_SPECIFIC ([0] OPTIONAL),
644 * its tag with the content is the payload of on OCTET STRING primitive */
645 authority_key_id->keyIdentifier.tag = MBEDTLS_ASN1_OCTET_STRING;
646
647 *p += len;
648 } else if (ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
649 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
650 }
651
652 if (*p < end) {
653 /* Getting authorityCertIssuer using the required specific class tag [1] */
654 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
655 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED |
656 1)) != 0) {
657 /* authorityCertIssuer and authorityCertSerialNumber MUST both
658 be present or both be absent. At this point we expect to have both. */
659 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
660 }
661 /* "end" also includes the CertSerialNumber field so "len" shall be used */
662 ret = mbedtls_x509_get_subject_alt_name_ext(p,
663 (*p+len),
664 &authority_key_id->authorityCertIssuer);
665 if (ret != 0) {
666 return ret;
667 }
668
669 /* Getting authorityCertSerialNumber using the required specific class tag [2] */
670 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
671 MBEDTLS_ASN1_CONTEXT_SPECIFIC | 2)) != 0) {
672 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
673 }
674 authority_key_id->authorityCertSerialNumber.len = len;
675 authority_key_id->authorityCertSerialNumber.p = *p;
676 authority_key_id->authorityCertSerialNumber.tag = MBEDTLS_ASN1_INTEGER;
677 *p += len;
678 }
679
680 if (*p != end) {
681 return MBEDTLS_ERR_X509_INVALID_EXTENSIONS +
682 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
683 }
684
685 return 0;
686 }
687
688 /*
689 * id-ce-certificatePolicies OBJECT IDENTIFIER ::= { id-ce 32 }
690 *
691 * anyPolicy OBJECT IDENTIFIER ::= { id-ce-certificatePolicies 0 }
692 *
693 * certificatePolicies ::= SEQUENCE SIZE (1..MAX) OF PolicyInformation
694 *
695 * PolicyInformation ::= SEQUENCE {
696 * policyIdentifier CertPolicyId,
697 * policyQualifiers SEQUENCE SIZE (1..MAX) OF
698 * PolicyQualifierInfo OPTIONAL }
699 *
700 * CertPolicyId ::= OBJECT IDENTIFIER
701 *
702 * PolicyQualifierInfo ::= SEQUENCE {
703 * policyQualifierId PolicyQualifierId,
704 * qualifier ANY DEFINED BY policyQualifierId }
705 *
706 * -- policyQualifierIds for Internet policy qualifiers
707 *
708 * id-qt OBJECT IDENTIFIER ::= { id-pkix 2 }
709 * id-qt-cps OBJECT IDENTIFIER ::= { id-qt 1 }
710 * id-qt-unotice OBJECT IDENTIFIER ::= { id-qt 2 }
711 *
712 * PolicyQualifierId ::= OBJECT IDENTIFIER ( id-qt-cps | id-qt-unotice )
713 *
714 * Qualifier ::= CHOICE {
715 * cPSuri CPSuri,
716 * userNotice UserNotice }
717 *
718 * CPSuri ::= IA5String
719 *
720 * UserNotice ::= SEQUENCE {
721 * noticeRef NoticeReference OPTIONAL,
722 * explicitText DisplayText OPTIONAL }
723 *
724 * NoticeReference ::= SEQUENCE {
725 * organization DisplayText,
726 * noticeNumbers SEQUENCE OF INTEGER }
727 *
728 * DisplayText ::= CHOICE {
729 * ia5String IA5String (SIZE (1..200)),
730 * visibleString VisibleString (SIZE (1..200)),
731 * bmpString BMPString (SIZE (1..200)),
732 * utf8String UTF8String (SIZE (1..200)) }
733 *
734 * NOTE: we only parse and use anyPolicy without qualifiers at this point
735 * as defined in RFC 5280.
736 */
x509_get_certificate_policies(unsigned char ** p,const unsigned char * end,mbedtls_x509_sequence * certificate_policies)737 static int x509_get_certificate_policies(unsigned char **p,
738 const unsigned char *end,
739 mbedtls_x509_sequence *certificate_policies)
740 {
741 int ret, parse_ret = 0;
742 size_t len;
743 mbedtls_asn1_buf *buf;
744 mbedtls_asn1_sequence *cur = certificate_policies;
745
746 /* Get main sequence tag */
747 ret = mbedtls_asn1_get_tag(p, end, &len,
748 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE);
749 if (ret != 0) {
750 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
751 }
752
753 if (*p + len != end) {
754 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
755 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
756 }
757
758 /*
759 * Cannot be an empty sequence.
760 */
761 if (len == 0) {
762 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
763 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
764 }
765
766 while (*p < end) {
767 mbedtls_x509_buf policy_oid;
768 const unsigned char *policy_end;
769
770 /*
771 * Get the policy sequence
772 */
773 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
774 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
775 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
776 }
777
778 policy_end = *p + len;
779
780 if ((ret = mbedtls_asn1_get_tag(p, policy_end, &len,
781 MBEDTLS_ASN1_OID)) != 0) {
782 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
783 }
784
785 policy_oid.tag = MBEDTLS_ASN1_OID;
786 policy_oid.len = len;
787 policy_oid.p = *p;
788
789 /*
790 * Only AnyPolicy is currently supported when enforcing policy.
791 */
792 if (MBEDTLS_OID_CMP(MBEDTLS_OID_ANY_POLICY, &policy_oid) != 0) {
793 /*
794 * Set the parsing return code but continue parsing, in case this
795 * extension is critical.
796 */
797 parse_ret = MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
798 }
799
800 /* Allocate and assign next pointer */
801 if (cur->buf.p != NULL) {
802 if (cur->next != NULL) {
803 return MBEDTLS_ERR_X509_INVALID_EXTENSIONS;
804 }
805
806 cur->next = mbedtls_calloc(1, sizeof(mbedtls_asn1_sequence));
807
808 if (cur->next == NULL) {
809 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
810 MBEDTLS_ERR_ASN1_ALLOC_FAILED);
811 }
812
813 cur = cur->next;
814 }
815
816 buf = &(cur->buf);
817 buf->tag = policy_oid.tag;
818 buf->p = policy_oid.p;
819 buf->len = policy_oid.len;
820
821 *p += len;
822
823 /*
824 * If there is an optional qualifier, then *p < policy_end
825 * Check the Qualifier len to verify it doesn't exceed policy_end.
826 */
827 if (*p < policy_end) {
828 if ((ret = mbedtls_asn1_get_tag(p, policy_end, &len,
829 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) !=
830 0) {
831 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
832 }
833 /*
834 * Skip the optional policy qualifiers.
835 */
836 *p += len;
837 }
838
839 if (*p != policy_end) {
840 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
841 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
842 }
843 }
844
845 /* Set final sequence entry's next pointer to NULL */
846 cur->next = NULL;
847
848 if (*p != end) {
849 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
850 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
851 }
852
853 return parse_ret;
854 }
855
856 /*
857 * X.509 v3 extensions
858 *
859 */
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)860 static int x509_get_crt_ext(unsigned char **p,
861 const unsigned char *end,
862 mbedtls_x509_crt *crt,
863 mbedtls_x509_crt_ext_cb_t cb,
864 void *p_ctx)
865 {
866 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
867 size_t len;
868 unsigned char *end_ext_data, *start_ext_octet, *end_ext_octet;
869
870 if (*p == end) {
871 return 0;
872 }
873
874 if ((ret = mbedtls_x509_get_ext(p, end, &crt->v3_ext, 3)) != 0) {
875 return ret;
876 }
877
878 end = crt->v3_ext.p + crt->v3_ext.len;
879 while (*p < end) {
880 /*
881 * Extension ::= SEQUENCE {
882 * extnID OBJECT IDENTIFIER,
883 * critical BOOLEAN DEFAULT FALSE,
884 * extnValue OCTET STRING }
885 */
886 mbedtls_x509_buf extn_oid = { 0, 0, NULL };
887 int is_critical = 0; /* DEFAULT FALSE */
888 int ext_type = 0;
889
890 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
891 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
892 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
893 }
894
895 end_ext_data = *p + len;
896
897 /* Get extension ID */
898 if ((ret = mbedtls_asn1_get_tag(p, end_ext_data, &extn_oid.len,
899 MBEDTLS_ASN1_OID)) != 0) {
900 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
901 }
902
903 extn_oid.tag = MBEDTLS_ASN1_OID;
904 extn_oid.p = *p;
905 *p += extn_oid.len;
906
907 /* Get optional critical */
908 if ((ret = mbedtls_asn1_get_bool(p, end_ext_data, &is_critical)) != 0 &&
909 (ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG)) {
910 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
911 }
912
913 /* Data should be octet string type */
914 if ((ret = mbedtls_asn1_get_tag(p, end_ext_data, &len,
915 MBEDTLS_ASN1_OCTET_STRING)) != 0) {
916 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS, ret);
917 }
918
919 start_ext_octet = *p;
920 end_ext_octet = *p + len;
921
922 if (end_ext_octet != end_ext_data) {
923 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
924 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
925 }
926
927 /*
928 * Detect supported extensions
929 */
930 ret = mbedtls_oid_get_x509_ext_type(&extn_oid, &ext_type);
931
932 if (ret != 0) {
933 /* Give the callback (if any) a chance to handle the extension */
934 if (cb != NULL) {
935 ret = cb(p_ctx, crt, &extn_oid, is_critical, *p, end_ext_octet);
936 if (ret != 0 && is_critical) {
937 return ret;
938 }
939 *p = end_ext_octet;
940 continue;
941 }
942
943 /* No parser found, skip extension */
944 *p = end_ext_octet;
945
946 if (is_critical) {
947 /* Data is marked as critical: fail */
948 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
949 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
950 }
951 continue;
952 }
953
954 /* Forbid repeated extensions */
955 if ((crt->ext_types & ext_type) != 0) {
956 return MBEDTLS_ERR_X509_INVALID_EXTENSIONS;
957 }
958
959 crt->ext_types |= ext_type;
960
961 switch (ext_type) {
962 case MBEDTLS_X509_EXT_BASIC_CONSTRAINTS:
963 /* Parse basic constraints */
964 if ((ret = x509_get_basic_constraints(p, end_ext_octet,
965 &crt->ca_istrue, &crt->max_pathlen)) != 0) {
966 return ret;
967 }
968 break;
969
970 case MBEDTLS_X509_EXT_KEY_USAGE:
971 /* Parse key usage */
972 if ((ret = mbedtls_x509_get_key_usage(p, end_ext_octet,
973 &crt->key_usage)) != 0) {
974 return ret;
975 }
976 break;
977
978 case MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE:
979 /* Parse extended key usage */
980 if ((ret = x509_get_ext_key_usage(p, end_ext_octet,
981 &crt->ext_key_usage)) != 0) {
982 return ret;
983 }
984 break;
985
986 case MBEDTLS_X509_EXT_SUBJECT_KEY_IDENTIFIER:
987 /* Parse subject key identifier */
988 if ((ret = x509_get_subject_key_id(p, end_ext_data,
989 &crt->subject_key_id)) != 0) {
990 return ret;
991 }
992 break;
993
994 case MBEDTLS_X509_EXT_AUTHORITY_KEY_IDENTIFIER:
995 /* Parse authority key identifier */
996 if ((ret = x509_get_authority_key_id(p, end_ext_octet,
997 &crt->authority_key_id)) != 0) {
998 return ret;
999 }
1000 break;
1001 case MBEDTLS_X509_EXT_SUBJECT_ALT_NAME:
1002 /* Parse subject alt name
1003 * SubjectAltName ::= GeneralNames
1004 */
1005 if ((ret = mbedtls_x509_get_subject_alt_name(p, end_ext_octet,
1006 &crt->subject_alt_names)) != 0) {
1007 return ret;
1008 }
1009 break;
1010
1011 case MBEDTLS_X509_EXT_NS_CERT_TYPE:
1012 /* Parse netscape certificate type */
1013 if ((ret = mbedtls_x509_get_ns_cert_type(p, end_ext_octet,
1014 &crt->ns_cert_type)) != 0) {
1015 return ret;
1016 }
1017 break;
1018
1019 case MBEDTLS_OID_X509_EXT_CERTIFICATE_POLICIES:
1020 /* Parse certificate policies type */
1021 if ((ret = x509_get_certificate_policies(p, end_ext_octet,
1022 &crt->certificate_policies)) != 0) {
1023 /* Give the callback (if any) a chance to handle the extension
1024 * if it contains unsupported policies */
1025 if (ret == MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE && cb != NULL &&
1026 cb(p_ctx, crt, &extn_oid, is_critical,
1027 start_ext_octet, end_ext_octet) == 0) {
1028 break;
1029 }
1030
1031 if (is_critical) {
1032 return ret;
1033 } else
1034 /*
1035 * If MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE is returned, then we
1036 * cannot interpret or enforce the policy. However, it is up to
1037 * the user to choose how to enforce the policies,
1038 * unless the extension is critical.
1039 */
1040 if (ret != MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE) {
1041 return ret;
1042 }
1043 }
1044 break;
1045
1046 default:
1047 /*
1048 * If this is a non-critical extension, which the oid layer
1049 * supports, but there isn't an x509 parser for it,
1050 * skip the extension.
1051 */
1052 if (is_critical) {
1053 return MBEDTLS_ERR_X509_FEATURE_UNAVAILABLE;
1054 } else {
1055 *p = end_ext_octet;
1056 }
1057 }
1058 }
1059
1060 if (*p != end) {
1061 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_EXTENSIONS,
1062 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
1063 }
1064
1065 return 0;
1066 }
1067
1068 /*
1069 * Parse and fill a single X.509 certificate in DER format
1070 */
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)1071 static int x509_crt_parse_der_core(mbedtls_x509_crt *crt,
1072 const unsigned char *buf,
1073 size_t buflen,
1074 int make_copy,
1075 mbedtls_x509_crt_ext_cb_t cb,
1076 void *p_ctx)
1077 {
1078 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1079 size_t len;
1080 unsigned char *p, *end, *crt_end;
1081 mbedtls_x509_buf sig_params1, sig_params2, sig_oid2;
1082
1083 memset(&sig_params1, 0, sizeof(mbedtls_x509_buf));
1084 memset(&sig_params2, 0, sizeof(mbedtls_x509_buf));
1085 memset(&sig_oid2, 0, sizeof(mbedtls_x509_buf));
1086
1087 /*
1088 * Check for valid input
1089 */
1090 if (crt == NULL || buf == NULL) {
1091 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1092 }
1093
1094 /* Use the original buffer until we figure out actual length. */
1095 p = (unsigned char *) buf;
1096 len = buflen;
1097 end = p + len;
1098
1099 /*
1100 * Certificate ::= SEQUENCE {
1101 * tbsCertificate TBSCertificate,
1102 * signatureAlgorithm AlgorithmIdentifier,
1103 * signatureValue BIT STRING }
1104 */
1105 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
1106 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
1107 mbedtls_x509_crt_free(crt);
1108 return MBEDTLS_ERR_X509_INVALID_FORMAT;
1109 }
1110
1111 end = crt_end = p + len;
1112 crt->raw.len = (size_t) (crt_end - buf);
1113 if (make_copy != 0) {
1114 /* Create and populate a new buffer for the raw field. */
1115 crt->raw.p = p = mbedtls_calloc(1, crt->raw.len);
1116 if (crt->raw.p == NULL) {
1117 return MBEDTLS_ERR_X509_ALLOC_FAILED;
1118 }
1119
1120 memcpy(crt->raw.p, buf, crt->raw.len);
1121 crt->own_buffer = 1;
1122
1123 p += crt->raw.len - len;
1124 end = crt_end = p + len;
1125 } else {
1126 crt->raw.p = (unsigned char *) buf;
1127 crt->own_buffer = 0;
1128 }
1129
1130 /*
1131 * TBSCertificate ::= SEQUENCE {
1132 */
1133 crt->tbs.p = p;
1134
1135 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
1136 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
1137 mbedtls_x509_crt_free(crt);
1138 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
1139 }
1140
1141 end = p + len;
1142 crt->tbs.len = (size_t) (end - crt->tbs.p);
1143
1144 /*
1145 * Version ::= INTEGER { v1(0), v2(1), v3(2) }
1146 *
1147 * CertificateSerialNumber ::= INTEGER
1148 *
1149 * signature AlgorithmIdentifier
1150 */
1151 if ((ret = x509_get_version(&p, end, &crt->version)) != 0 ||
1152 (ret = mbedtls_x509_get_serial(&p, end, &crt->serial)) != 0 ||
1153 (ret = mbedtls_x509_get_alg(&p, end, &crt->sig_oid,
1154 &sig_params1)) != 0) {
1155 mbedtls_x509_crt_free(crt);
1156 return ret;
1157 }
1158
1159 if (crt->version < 0 || crt->version > 2) {
1160 mbedtls_x509_crt_free(crt);
1161 return MBEDTLS_ERR_X509_UNKNOWN_VERSION;
1162 }
1163
1164 crt->version++;
1165
1166 if ((ret = mbedtls_x509_get_sig_alg(&crt->sig_oid, &sig_params1,
1167 &crt->sig_md, &crt->sig_pk,
1168 &crt->sig_opts)) != 0) {
1169 mbedtls_x509_crt_free(crt);
1170 return ret;
1171 }
1172
1173 /*
1174 * issuer Name
1175 */
1176 crt->issuer_raw.p = p;
1177
1178 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
1179 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
1180 mbedtls_x509_crt_free(crt);
1181 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
1182 }
1183
1184 if ((ret = mbedtls_x509_get_name(&p, p + len, &crt->issuer)) != 0) {
1185 mbedtls_x509_crt_free(crt);
1186 return ret;
1187 }
1188
1189 crt->issuer_raw.len = (size_t) (p - crt->issuer_raw.p);
1190
1191 /*
1192 * Validity ::= SEQUENCE {
1193 * notBefore Time,
1194 * notAfter Time }
1195 *
1196 */
1197 if ((ret = x509_get_dates(&p, end, &crt->valid_from,
1198 &crt->valid_to)) != 0) {
1199 mbedtls_x509_crt_free(crt);
1200 return ret;
1201 }
1202
1203 /*
1204 * subject Name
1205 */
1206 crt->subject_raw.p = p;
1207
1208 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
1209 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
1210 mbedtls_x509_crt_free(crt);
1211 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT, ret);
1212 }
1213
1214 if (len && (ret = mbedtls_x509_get_name(&p, p + len, &crt->subject)) != 0) {
1215 mbedtls_x509_crt_free(crt);
1216 return ret;
1217 }
1218
1219 crt->subject_raw.len = (size_t) (p - crt->subject_raw.p);
1220
1221 /*
1222 * SubjectPublicKeyInfo
1223 */
1224 crt->pk_raw.p = p;
1225 if ((ret = mbedtls_pk_parse_subpubkey(&p, end, &crt->pk)) != 0) {
1226 mbedtls_x509_crt_free(crt);
1227 return ret;
1228 }
1229 crt->pk_raw.len = (size_t) (p - crt->pk_raw.p);
1230
1231 /*
1232 * issuerUniqueID [1] IMPLICIT UniqueIdentifier OPTIONAL,
1233 * -- If present, version shall be v2 or v3
1234 * subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
1235 * -- If present, version shall be v2 or v3
1236 * extensions [3] EXPLICIT Extensions OPTIONAL
1237 * -- If present, version shall be v3
1238 */
1239 if (crt->version == 2 || crt->version == 3) {
1240 ret = x509_get_uid(&p, end, &crt->issuer_id, 1);
1241 if (ret != 0) {
1242 mbedtls_x509_crt_free(crt);
1243 return ret;
1244 }
1245 }
1246
1247 if (crt->version == 2 || crt->version == 3) {
1248 ret = x509_get_uid(&p, end, &crt->subject_id, 2);
1249 if (ret != 0) {
1250 mbedtls_x509_crt_free(crt);
1251 return ret;
1252 }
1253 }
1254
1255 if (crt->version == 3) {
1256 ret = x509_get_crt_ext(&p, end, crt, cb, p_ctx);
1257 if (ret != 0) {
1258 mbedtls_x509_crt_free(crt);
1259 return ret;
1260 }
1261 }
1262
1263 if (p != end) {
1264 mbedtls_x509_crt_free(crt);
1265 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT,
1266 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
1267 }
1268
1269 end = crt_end;
1270
1271 /*
1272 * }
1273 * -- end of TBSCertificate
1274 *
1275 * signatureAlgorithm AlgorithmIdentifier,
1276 * signatureValue BIT STRING
1277 */
1278 if ((ret = mbedtls_x509_get_alg(&p, end, &sig_oid2, &sig_params2)) != 0) {
1279 mbedtls_x509_crt_free(crt);
1280 return ret;
1281 }
1282
1283 if (crt->sig_oid.len != sig_oid2.len ||
1284 memcmp(crt->sig_oid.p, sig_oid2.p, crt->sig_oid.len) != 0 ||
1285 sig_params1.tag != sig_params2.tag ||
1286 sig_params1.len != sig_params2.len ||
1287 (sig_params1.len != 0 &&
1288 memcmp(sig_params1.p, sig_params2.p, sig_params1.len) != 0)) {
1289 mbedtls_x509_crt_free(crt);
1290 return MBEDTLS_ERR_X509_SIG_MISMATCH;
1291 }
1292
1293 if ((ret = mbedtls_x509_get_sig(&p, end, &crt->sig)) != 0) {
1294 mbedtls_x509_crt_free(crt);
1295 return ret;
1296 }
1297
1298 if (p != end) {
1299 mbedtls_x509_crt_free(crt);
1300 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_INVALID_FORMAT,
1301 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
1302 }
1303
1304 return 0;
1305 }
1306
1307 /*
1308 * Parse one X.509 certificate in DER format from a buffer and add them to a
1309 * chained list
1310 */
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)1311 static int mbedtls_x509_crt_parse_der_internal(mbedtls_x509_crt *chain,
1312 const unsigned char *buf,
1313 size_t buflen,
1314 int make_copy,
1315 mbedtls_x509_crt_ext_cb_t cb,
1316 void *p_ctx)
1317 {
1318 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1319 mbedtls_x509_crt *crt = chain, *prev = NULL;
1320
1321 /*
1322 * Check for valid input
1323 */
1324 if (crt == NULL || buf == NULL) {
1325 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1326 }
1327
1328 while (crt->version != 0 && crt->next != NULL) {
1329 prev = crt;
1330 crt = crt->next;
1331 }
1332
1333 /*
1334 * Add new certificate on the end of the chain if needed.
1335 */
1336 if (crt->version != 0 && crt->next == NULL) {
1337 crt->next = mbedtls_calloc(1, sizeof(mbedtls_x509_crt));
1338
1339 if (crt->next == NULL) {
1340 return MBEDTLS_ERR_X509_ALLOC_FAILED;
1341 }
1342
1343 prev = crt;
1344 mbedtls_x509_crt_init(crt->next);
1345 crt = crt->next;
1346 }
1347
1348 ret = x509_crt_parse_der_core(crt, buf, buflen, make_copy, cb, p_ctx);
1349 if (ret != 0) {
1350 if (prev) {
1351 prev->next = NULL;
1352 }
1353
1354 if (crt != chain) {
1355 mbedtls_free(crt);
1356 }
1357
1358 return ret;
1359 }
1360
1361 return 0;
1362 }
1363
mbedtls_x509_crt_parse_der_nocopy(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)1364 int mbedtls_x509_crt_parse_der_nocopy(mbedtls_x509_crt *chain,
1365 const unsigned char *buf,
1366 size_t buflen)
1367 {
1368 return mbedtls_x509_crt_parse_der_internal(chain, buf, buflen, 0, NULL, NULL);
1369 }
1370
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)1371 int mbedtls_x509_crt_parse_der_with_ext_cb(mbedtls_x509_crt *chain,
1372 const unsigned char *buf,
1373 size_t buflen,
1374 int make_copy,
1375 mbedtls_x509_crt_ext_cb_t cb,
1376 void *p_ctx)
1377 {
1378 return mbedtls_x509_crt_parse_der_internal(chain, buf, buflen, make_copy, cb, p_ctx);
1379 }
1380
mbedtls_x509_crt_parse_der(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)1381 int mbedtls_x509_crt_parse_der(mbedtls_x509_crt *chain,
1382 const unsigned char *buf,
1383 size_t buflen)
1384 {
1385 return mbedtls_x509_crt_parse_der_internal(chain, buf, buflen, 1, NULL, NULL);
1386 }
1387
1388 /*
1389 * Parse one or more PEM certificates from a buffer and add them to the chained
1390 * list
1391 */
mbedtls_x509_crt_parse(mbedtls_x509_crt * chain,const unsigned char * buf,size_t buflen)1392 int mbedtls_x509_crt_parse(mbedtls_x509_crt *chain,
1393 const unsigned char *buf,
1394 size_t buflen)
1395 {
1396 #if defined(MBEDTLS_PEM_PARSE_C)
1397 int success = 0, first_error = 0, total_failed = 0;
1398 int buf_format = MBEDTLS_X509_FORMAT_DER;
1399 #endif
1400
1401 /*
1402 * Check for valid input
1403 */
1404 if (chain == NULL || buf == NULL) {
1405 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1406 }
1407
1408 /*
1409 * Determine buffer content. Buffer contains either one DER certificate or
1410 * one or more PEM certificates.
1411 */
1412 #if defined(MBEDTLS_PEM_PARSE_C)
1413 if (buflen != 0 && buf[buflen - 1] == '\0' &&
1414 strstr((const char *) buf, "-----BEGIN CERTIFICATE-----") != NULL) {
1415 buf_format = MBEDTLS_X509_FORMAT_PEM;
1416 }
1417
1418 if (buf_format == MBEDTLS_X509_FORMAT_DER) {
1419 return mbedtls_x509_crt_parse_der(chain, buf, buflen);
1420 }
1421 #else
1422 return mbedtls_x509_crt_parse_der(chain, buf, buflen);
1423 #endif
1424
1425 #if defined(MBEDTLS_PEM_PARSE_C)
1426 if (buf_format == MBEDTLS_X509_FORMAT_PEM) {
1427 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1428 mbedtls_pem_context pem;
1429
1430 /* 1 rather than 0 since the terminating NULL byte is counted in */
1431 while (buflen > 1) {
1432 size_t use_len;
1433 mbedtls_pem_init(&pem);
1434
1435 /* If we get there, we know the string is null-terminated */
1436 ret = mbedtls_pem_read_buffer(&pem,
1437 "-----BEGIN CERTIFICATE-----",
1438 "-----END CERTIFICATE-----",
1439 buf, NULL, 0, &use_len);
1440
1441 if (ret == 0) {
1442 /*
1443 * Was PEM encoded
1444 */
1445 buflen -= use_len;
1446 buf += use_len;
1447 } else if (ret == MBEDTLS_ERR_PEM_BAD_INPUT_DATA) {
1448 return ret;
1449 } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
1450 mbedtls_pem_free(&pem);
1451
1452 /*
1453 * PEM header and footer were found
1454 */
1455 buflen -= use_len;
1456 buf += use_len;
1457
1458 if (first_error == 0) {
1459 first_error = ret;
1460 }
1461
1462 total_failed++;
1463 continue;
1464 } else {
1465 break;
1466 }
1467
1468 ret = mbedtls_x509_crt_parse_der(chain, pem.buf, pem.buflen);
1469
1470 mbedtls_pem_free(&pem);
1471
1472 if (ret != 0) {
1473 /*
1474 * Quit parsing on a memory error
1475 */
1476 if (ret == MBEDTLS_ERR_X509_ALLOC_FAILED) {
1477 return ret;
1478 }
1479
1480 if (first_error == 0) {
1481 first_error = ret;
1482 }
1483
1484 total_failed++;
1485 continue;
1486 }
1487
1488 success = 1;
1489 }
1490 }
1491
1492 if (success) {
1493 return total_failed;
1494 } else if (first_error) {
1495 return first_error;
1496 } else {
1497 return MBEDTLS_ERR_X509_CERT_UNKNOWN_FORMAT;
1498 }
1499 #endif /* MBEDTLS_PEM_PARSE_C */
1500 }
1501
1502 #if defined(MBEDTLS_FS_IO)
1503 /*
1504 * Load one or more certificates and add them to the chained list
1505 */
mbedtls_x509_crt_parse_file(mbedtls_x509_crt * chain,const char * path)1506 int mbedtls_x509_crt_parse_file(mbedtls_x509_crt *chain, const char *path)
1507 {
1508 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1509 size_t n;
1510 unsigned char *buf;
1511
1512 if ((ret = mbedtls_pk_load_file(path, &buf, &n)) != 0) {
1513 return ret;
1514 }
1515
1516 ret = mbedtls_x509_crt_parse(chain, buf, n);
1517
1518 mbedtls_zeroize_and_free(buf, n);
1519
1520 return ret;
1521 }
1522
mbedtls_x509_crt_parse_path(mbedtls_x509_crt * chain,const char * path)1523 int mbedtls_x509_crt_parse_path(mbedtls_x509_crt *chain, const char *path)
1524 {
1525 int ret = 0;
1526 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
1527 int w_ret;
1528 WCHAR szDir[MAX_PATH];
1529 char filename[MAX_PATH];
1530 char *p;
1531 size_t len = strlen(path);
1532
1533 WIN32_FIND_DATAW file_data;
1534 HANDLE hFind;
1535
1536 if (len > MAX_PATH - 3) {
1537 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1538 }
1539
1540 memset(szDir, 0, sizeof(szDir));
1541 memset(filename, 0, MAX_PATH);
1542 memcpy(filename, path, len);
1543 filename[len++] = '\\';
1544 p = filename + len;
1545 filename[len++] = '*';
1546
1547 /*
1548 * Note this function uses the code page CP_ACP which is the system default
1549 * ANSI codepage. The input string is always described in BYTES and the
1550 * output length is described in WCHARs.
1551 */
1552 w_ret = MultiByteToWideChar(CP_ACP, 0, filename, (int) len, szDir,
1553 MAX_PATH - 3);
1554 if (w_ret == 0) {
1555 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1556 }
1557
1558 hFind = FindFirstFileW(szDir, &file_data);
1559 if (hFind == INVALID_HANDLE_VALUE) {
1560 return MBEDTLS_ERR_X509_FILE_IO_ERROR;
1561 }
1562
1563 len = MAX_PATH - len;
1564 do {
1565 memset(p, 0, len);
1566
1567 if (file_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
1568 continue;
1569 }
1570 w_ret = WideCharToMultiByte(CP_ACP, 0, file_data.cFileName,
1571 -1, p, (int) len, NULL, NULL);
1572 if (w_ret == 0) {
1573 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1574 goto cleanup;
1575 }
1576
1577 w_ret = mbedtls_x509_crt_parse_file(chain, filename);
1578 if (w_ret < 0) {
1579 ret++;
1580 } else {
1581 ret += w_ret;
1582 }
1583 } while (FindNextFileW(hFind, &file_data) != 0);
1584
1585 if (GetLastError() != ERROR_NO_MORE_FILES) {
1586 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1587 }
1588
1589 cleanup:
1590 FindClose(hFind);
1591 #else /* _WIN32 */
1592 int t_ret;
1593 int snp_ret;
1594 struct stat sb;
1595 struct dirent *entry;
1596 char entry_name[MBEDTLS_X509_MAX_FILE_PATH_LEN];
1597 DIR *dir = opendir(path);
1598
1599 if (dir == NULL) {
1600 return MBEDTLS_ERR_X509_FILE_IO_ERROR;
1601 }
1602
1603 #if defined(MBEDTLS_THREADING_C)
1604 if ((ret = mbedtls_mutex_lock(&mbedtls_threading_readdir_mutex)) != 0) {
1605 closedir(dir);
1606 return ret;
1607 }
1608 #endif /* MBEDTLS_THREADING_C */
1609
1610 memset(&sb, 0, sizeof(sb));
1611
1612 while ((entry = readdir(dir)) != NULL) {
1613 snp_ret = mbedtls_snprintf(entry_name, sizeof(entry_name),
1614 "%s/%s", path, entry->d_name);
1615
1616 if (snp_ret < 0 || (size_t) snp_ret >= sizeof(entry_name)) {
1617 ret = MBEDTLS_ERR_X509_BUFFER_TOO_SMALL;
1618 goto cleanup;
1619 } else if (stat(entry_name, &sb) == -1) {
1620 if (errno == ENOENT) {
1621 /* Broken symbolic link - ignore this entry.
1622 stat(2) will return this error for either (a) a dangling
1623 symlink or (b) a missing file.
1624 Given that we have just obtained the filename from readdir,
1625 assume that it does exist and therefore treat this as a
1626 dangling symlink. */
1627 continue;
1628 } else {
1629 /* Some other file error; report the error. */
1630 ret = MBEDTLS_ERR_X509_FILE_IO_ERROR;
1631 goto cleanup;
1632 }
1633 }
1634
1635 if (!S_ISREG(sb.st_mode)) {
1636 continue;
1637 }
1638
1639 // Ignore parse errors
1640 //
1641 t_ret = mbedtls_x509_crt_parse_file(chain, entry_name);
1642 if (t_ret < 0) {
1643 ret++;
1644 } else {
1645 ret += t_ret;
1646 }
1647 }
1648
1649 cleanup:
1650 closedir(dir);
1651
1652 #if defined(MBEDTLS_THREADING_C)
1653 if (mbedtls_mutex_unlock(&mbedtls_threading_readdir_mutex) != 0) {
1654 ret = MBEDTLS_ERR_THREADING_MUTEX_ERROR;
1655 }
1656 #endif /* MBEDTLS_THREADING_C */
1657
1658 #endif /* _WIN32 */
1659
1660 return ret;
1661 }
1662 #endif /* MBEDTLS_FS_IO */
1663
1664 #if !defined(MBEDTLS_X509_REMOVE_INFO)
1665 #define PRINT_ITEM(i) \
1666 do { \
1667 ret = mbedtls_snprintf(p, n, "%s" i, sep); \
1668 MBEDTLS_X509_SAFE_SNPRINTF; \
1669 sep = ", "; \
1670 } while (0)
1671
1672 #define CERT_TYPE(type, name) \
1673 do { \
1674 if (ns_cert_type & (type)) { \
1675 PRINT_ITEM(name); \
1676 } \
1677 } while (0)
1678
1679 #define KEY_USAGE(code, name) \
1680 do { \
1681 if (key_usage & (code)) { \
1682 PRINT_ITEM(name); \
1683 } \
1684 } while (0)
1685
x509_info_ext_key_usage(char ** buf,size_t * size,const mbedtls_x509_sequence * extended_key_usage)1686 static int x509_info_ext_key_usage(char **buf, size_t *size,
1687 const mbedtls_x509_sequence *extended_key_usage)
1688 {
1689 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1690 const char *desc;
1691 size_t n = *size;
1692 char *p = *buf;
1693 const mbedtls_x509_sequence *cur = extended_key_usage;
1694 const char *sep = "";
1695
1696 while (cur != NULL) {
1697 if (mbedtls_oid_get_extended_key_usage(&cur->buf, &desc) != 0) {
1698 desc = "???";
1699 }
1700
1701 ret = mbedtls_snprintf(p, n, "%s%s", sep, desc);
1702 MBEDTLS_X509_SAFE_SNPRINTF;
1703
1704 sep = ", ";
1705
1706 cur = cur->next;
1707 }
1708
1709 *size = n;
1710 *buf = p;
1711
1712 return 0;
1713 }
1714
x509_info_cert_policies(char ** buf,size_t * size,const mbedtls_x509_sequence * certificate_policies)1715 static int x509_info_cert_policies(char **buf, size_t *size,
1716 const mbedtls_x509_sequence *certificate_policies)
1717 {
1718 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1719 const char *desc;
1720 size_t n = *size;
1721 char *p = *buf;
1722 const mbedtls_x509_sequence *cur = certificate_policies;
1723 const char *sep = "";
1724
1725 while (cur != NULL) {
1726 if (mbedtls_oid_get_certificate_policies(&cur->buf, &desc) != 0) {
1727 desc = "???";
1728 }
1729
1730 ret = mbedtls_snprintf(p, n, "%s%s", sep, desc);
1731 MBEDTLS_X509_SAFE_SNPRINTF;
1732
1733 sep = ", ";
1734
1735 cur = cur->next;
1736 }
1737
1738 *size = n;
1739 *buf = p;
1740
1741 return 0;
1742 }
1743
1744 /*
1745 * Return an informational string about the certificate.
1746 */
1747 #define BEFORE_COLON 18
1748 #define BC "18"
mbedtls_x509_crt_info(char * buf,size_t size,const char * prefix,const mbedtls_x509_crt * crt)1749 int mbedtls_x509_crt_info(char *buf, size_t size, const char *prefix,
1750 const mbedtls_x509_crt *crt)
1751 {
1752 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1753 size_t n;
1754 char *p;
1755 char key_size_str[BEFORE_COLON];
1756
1757 p = buf;
1758 n = size;
1759
1760 if (NULL == crt) {
1761 ret = mbedtls_snprintf(p, n, "\nCertificate is uninitialised!\n");
1762 MBEDTLS_X509_SAFE_SNPRINTF;
1763
1764 return (int) (size - n);
1765 }
1766
1767 ret = mbedtls_snprintf(p, n, "%scert. version : %d\n",
1768 prefix, crt->version);
1769 MBEDTLS_X509_SAFE_SNPRINTF;
1770 ret = mbedtls_snprintf(p, n, "%sserial number : ",
1771 prefix);
1772 MBEDTLS_X509_SAFE_SNPRINTF;
1773
1774 ret = mbedtls_x509_serial_gets(p, n, &crt->serial);
1775 MBEDTLS_X509_SAFE_SNPRINTF;
1776
1777 ret = mbedtls_snprintf(p, n, "\n%sissuer name : ", prefix);
1778 MBEDTLS_X509_SAFE_SNPRINTF;
1779 ret = mbedtls_x509_dn_gets(p, n, &crt->issuer);
1780 MBEDTLS_X509_SAFE_SNPRINTF;
1781
1782 ret = mbedtls_snprintf(p, n, "\n%ssubject name : ", prefix);
1783 MBEDTLS_X509_SAFE_SNPRINTF;
1784 ret = mbedtls_x509_dn_gets(p, n, &crt->subject);
1785 MBEDTLS_X509_SAFE_SNPRINTF;
1786
1787 ret = mbedtls_snprintf(p, n, "\n%sissued on : " \
1788 "%04d-%02d-%02d %02d:%02d:%02d", prefix,
1789 crt->valid_from.year, crt->valid_from.mon,
1790 crt->valid_from.day, crt->valid_from.hour,
1791 crt->valid_from.min, crt->valid_from.sec);
1792 MBEDTLS_X509_SAFE_SNPRINTF;
1793
1794 ret = mbedtls_snprintf(p, n, "\n%sexpires on : " \
1795 "%04d-%02d-%02d %02d:%02d:%02d", prefix,
1796 crt->valid_to.year, crt->valid_to.mon,
1797 crt->valid_to.day, crt->valid_to.hour,
1798 crt->valid_to.min, crt->valid_to.sec);
1799 MBEDTLS_X509_SAFE_SNPRINTF;
1800
1801 ret = mbedtls_snprintf(p, n, "\n%ssigned using : ", prefix);
1802 MBEDTLS_X509_SAFE_SNPRINTF;
1803
1804 ret = mbedtls_x509_sig_alg_gets(p, n, &crt->sig_oid, crt->sig_pk,
1805 crt->sig_md, crt->sig_opts);
1806 MBEDTLS_X509_SAFE_SNPRINTF;
1807
1808 /* Key size */
1809 if ((ret = mbedtls_x509_key_size_helper(key_size_str, BEFORE_COLON,
1810 mbedtls_pk_get_name(&crt->pk))) != 0) {
1811 return ret;
1812 }
1813
1814 ret = mbedtls_snprintf(p, n, "\n%s%-" BC "s: %d bits", prefix, key_size_str,
1815 (int) mbedtls_pk_get_bitlen(&crt->pk));
1816 MBEDTLS_X509_SAFE_SNPRINTF;
1817
1818 /*
1819 * Optional extensions
1820 */
1821
1822 if (crt->ext_types & MBEDTLS_X509_EXT_BASIC_CONSTRAINTS) {
1823 ret = mbedtls_snprintf(p, n, "\n%sbasic constraints : CA=%s", prefix,
1824 crt->ca_istrue ? "true" : "false");
1825 MBEDTLS_X509_SAFE_SNPRINTF;
1826
1827 if (crt->max_pathlen > 0) {
1828 ret = mbedtls_snprintf(p, n, ", max_pathlen=%d", crt->max_pathlen - 1);
1829 MBEDTLS_X509_SAFE_SNPRINTF;
1830 }
1831 }
1832
1833 if (crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME) {
1834 ret = mbedtls_snprintf(p, n, "\n%ssubject alt name :", prefix);
1835 MBEDTLS_X509_SAFE_SNPRINTF;
1836
1837 if ((ret = mbedtls_x509_info_subject_alt_name(&p, &n,
1838 &crt->subject_alt_names,
1839 prefix)) != 0) {
1840 return ret;
1841 }
1842 }
1843
1844 if (crt->ext_types & MBEDTLS_X509_EXT_NS_CERT_TYPE) {
1845 ret = mbedtls_snprintf(p, n, "\n%scert. type : ", prefix);
1846 MBEDTLS_X509_SAFE_SNPRINTF;
1847
1848 if ((ret = mbedtls_x509_info_cert_type(&p, &n, crt->ns_cert_type)) != 0) {
1849 return ret;
1850 }
1851 }
1852
1853 if (crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE) {
1854 ret = mbedtls_snprintf(p, n, "\n%skey usage : ", prefix);
1855 MBEDTLS_X509_SAFE_SNPRINTF;
1856
1857 if ((ret = mbedtls_x509_info_key_usage(&p, &n, crt->key_usage)) != 0) {
1858 return ret;
1859 }
1860 }
1861
1862 if (crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE) {
1863 ret = mbedtls_snprintf(p, n, "\n%sext key usage : ", prefix);
1864 MBEDTLS_X509_SAFE_SNPRINTF;
1865
1866 if ((ret = x509_info_ext_key_usage(&p, &n,
1867 &crt->ext_key_usage)) != 0) {
1868 return ret;
1869 }
1870 }
1871
1872 if (crt->ext_types & MBEDTLS_OID_X509_EXT_CERTIFICATE_POLICIES) {
1873 ret = mbedtls_snprintf(p, n, "\n%scertificate policies : ", prefix);
1874 MBEDTLS_X509_SAFE_SNPRINTF;
1875
1876 if ((ret = x509_info_cert_policies(&p, &n,
1877 &crt->certificate_policies)) != 0) {
1878 return ret;
1879 }
1880 }
1881
1882 ret = mbedtls_snprintf(p, n, "\n");
1883 MBEDTLS_X509_SAFE_SNPRINTF;
1884
1885 return (int) (size - n);
1886 }
1887
1888 struct x509_crt_verify_string {
1889 int code;
1890 const char *string;
1891 };
1892
1893 #define X509_CRT_ERROR_INFO(err, err_str, info) { err, info },
1894 static const struct x509_crt_verify_string x509_crt_verify_strings[] = {
1895 MBEDTLS_X509_CRT_ERROR_INFO_LIST
1896 { 0, NULL }
1897 };
1898 #undef X509_CRT_ERROR_INFO
1899
mbedtls_x509_crt_verify_info(char * buf,size_t size,const char * prefix,uint32_t flags)1900 int mbedtls_x509_crt_verify_info(char *buf, size_t size, const char *prefix,
1901 uint32_t flags)
1902 {
1903 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1904 const struct x509_crt_verify_string *cur;
1905 char *p = buf;
1906 size_t n = size;
1907
1908 for (cur = x509_crt_verify_strings; cur->string != NULL; cur++) {
1909 if ((flags & cur->code) == 0) {
1910 continue;
1911 }
1912
1913 ret = mbedtls_snprintf(p, n, "%s%s\n", prefix, cur->string);
1914 MBEDTLS_X509_SAFE_SNPRINTF;
1915 flags ^= cur->code;
1916 }
1917
1918 if (flags != 0) {
1919 ret = mbedtls_snprintf(p, n, "%sUnknown reason "
1920 "(this should not happen)\n", prefix);
1921 MBEDTLS_X509_SAFE_SNPRINTF;
1922 }
1923
1924 return (int) (size - n);
1925 }
1926 #endif /* MBEDTLS_X509_REMOVE_INFO */
1927
mbedtls_x509_crt_check_key_usage(const mbedtls_x509_crt * crt,unsigned int usage)1928 int mbedtls_x509_crt_check_key_usage(const mbedtls_x509_crt *crt,
1929 unsigned int usage)
1930 {
1931 unsigned int usage_must, usage_may;
1932 unsigned int may_mask = MBEDTLS_X509_KU_ENCIPHER_ONLY
1933 | MBEDTLS_X509_KU_DECIPHER_ONLY;
1934
1935 if ((crt->ext_types & MBEDTLS_X509_EXT_KEY_USAGE) == 0) {
1936 return 0;
1937 }
1938
1939 usage_must = usage & ~may_mask;
1940
1941 if (((crt->key_usage & ~may_mask) & usage_must) != usage_must) {
1942 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1943 }
1944
1945 usage_may = usage & may_mask;
1946
1947 if (((crt->key_usage & may_mask) | usage_may) != usage_may) {
1948 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1949 }
1950
1951 return 0;
1952 }
1953
mbedtls_x509_crt_check_extended_key_usage(const mbedtls_x509_crt * crt,const char * usage_oid,size_t usage_len)1954 int mbedtls_x509_crt_check_extended_key_usage(const mbedtls_x509_crt *crt,
1955 const char *usage_oid,
1956 size_t usage_len)
1957 {
1958 const mbedtls_x509_sequence *cur;
1959
1960 /* Extension is not mandatory, absent means no restriction */
1961 if ((crt->ext_types & MBEDTLS_X509_EXT_EXTENDED_KEY_USAGE) == 0) {
1962 return 0;
1963 }
1964
1965 /*
1966 * Look for the requested usage (or wildcard ANY) in our list
1967 */
1968 for (cur = &crt->ext_key_usage; cur != NULL; cur = cur->next) {
1969 const mbedtls_x509_buf *cur_oid = &cur->buf;
1970
1971 if (cur_oid->len == usage_len &&
1972 memcmp(cur_oid->p, usage_oid, usage_len) == 0) {
1973 return 0;
1974 }
1975
1976 if (MBEDTLS_OID_CMP(MBEDTLS_OID_ANY_EXTENDED_KEY_USAGE, cur_oid) == 0) {
1977 return 0;
1978 }
1979 }
1980
1981 return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
1982 }
1983
1984 #if defined(MBEDTLS_X509_CRL_PARSE_C)
1985 /*
1986 * Return 1 if the certificate is revoked, or 0 otherwise.
1987 */
mbedtls_x509_crt_is_revoked(const mbedtls_x509_crt * crt,const mbedtls_x509_crl * crl)1988 int mbedtls_x509_crt_is_revoked(const mbedtls_x509_crt *crt, const mbedtls_x509_crl *crl)
1989 {
1990 const mbedtls_x509_crl_entry *cur = &crl->entry;
1991
1992 while (cur != NULL && cur->serial.len != 0) {
1993 if (crt->serial.len == cur->serial.len &&
1994 memcmp(crt->serial.p, cur->serial.p, crt->serial.len) == 0) {
1995 return 1;
1996 }
1997
1998 cur = cur->next;
1999 }
2000
2001 return 0;
2002 }
2003
2004 /*
2005 * Check that the given certificate is not revoked according to the CRL.
2006 * Skip validation if no CRL for the given CA is present.
2007 */
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)2008 static int x509_crt_verifycrl(mbedtls_x509_crt *crt, mbedtls_x509_crt *ca,
2009 mbedtls_x509_crl *crl_list,
2010 const mbedtls_x509_crt_profile *profile,
2011 const mbedtls_x509_time *now)
2012 {
2013 int flags = 0;
2014 unsigned char hash[MBEDTLS_MD_MAX_SIZE];
2015 #if defined(MBEDTLS_USE_PSA_CRYPTO)
2016 psa_algorithm_t psa_algorithm;
2017 #else
2018 const mbedtls_md_info_t *md_info;
2019 #endif /* MBEDTLS_USE_PSA_CRYPTO */
2020 size_t hash_length;
2021
2022 if (ca == NULL) {
2023 return flags;
2024 }
2025
2026 while (crl_list != NULL) {
2027 if (crl_list->version == 0 ||
2028 x509_name_cmp(&crl_list->issuer, &ca->subject) != 0) {
2029 crl_list = crl_list->next;
2030 continue;
2031 }
2032
2033 /*
2034 * Check if the CA is configured to sign CRLs
2035 */
2036 if (mbedtls_x509_crt_check_key_usage(ca,
2037 MBEDTLS_X509_KU_CRL_SIGN) != 0) {
2038 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
2039 break;
2040 }
2041
2042 /*
2043 * Check if CRL is correctly signed by the trusted CA
2044 */
2045 if (x509_profile_check_md_alg(profile, crl_list->sig_md) != 0) {
2046 flags |= MBEDTLS_X509_BADCRL_BAD_MD;
2047 }
2048
2049 if (x509_profile_check_pk_alg(profile, crl_list->sig_pk) != 0) {
2050 flags |= MBEDTLS_X509_BADCRL_BAD_PK;
2051 }
2052
2053 #if defined(MBEDTLS_USE_PSA_CRYPTO)
2054 psa_algorithm = mbedtls_md_psa_alg_from_type(crl_list->sig_md);
2055 if (psa_hash_compute(psa_algorithm,
2056 crl_list->tbs.p,
2057 crl_list->tbs.len,
2058 hash,
2059 sizeof(hash),
2060 &hash_length) != PSA_SUCCESS) {
2061 /* Note: this can't happen except after an internal error */
2062 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
2063 break;
2064 }
2065 #else
2066 md_info = mbedtls_md_info_from_type(crl_list->sig_md);
2067 hash_length = mbedtls_md_get_size(md_info);
2068 if (mbedtls_md(md_info,
2069 crl_list->tbs.p,
2070 crl_list->tbs.len,
2071 hash) != 0) {
2072 /* Note: this can't happen except after an internal error */
2073 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
2074 break;
2075 }
2076 #endif /* MBEDTLS_USE_PSA_CRYPTO */
2077
2078 if (x509_profile_check_key(profile, &ca->pk) != 0) {
2079 flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
2080 }
2081
2082 if (mbedtls_pk_verify_ext(crl_list->sig_pk, crl_list->sig_opts, &ca->pk,
2083 crl_list->sig_md, hash, hash_length,
2084 crl_list->sig.p, crl_list->sig.len) != 0) {
2085 flags |= MBEDTLS_X509_BADCRL_NOT_TRUSTED;
2086 break;
2087 }
2088
2089 #if defined(MBEDTLS_HAVE_TIME_DATE)
2090 /*
2091 * Check for validity of CRL (Do not drop out)
2092 */
2093 if (mbedtls_x509_time_cmp(&crl_list->next_update, now) < 0) {
2094 flags |= MBEDTLS_X509_BADCRL_EXPIRED;
2095 }
2096
2097 if (mbedtls_x509_time_cmp(&crl_list->this_update, now) > 0) {
2098 flags |= MBEDTLS_X509_BADCRL_FUTURE;
2099 }
2100 #else
2101 ((void) now);
2102 #endif
2103
2104 /*
2105 * Check if certificate is revoked
2106 */
2107 if (mbedtls_x509_crt_is_revoked(crt, crl_list)) {
2108 flags |= MBEDTLS_X509_BADCERT_REVOKED;
2109 break;
2110 }
2111
2112 crl_list = crl_list->next;
2113 }
2114
2115 return flags;
2116 }
2117 #endif /* MBEDTLS_X509_CRL_PARSE_C */
2118
2119 /*
2120 * Check the signature of a certificate by its parent
2121 */
x509_crt_check_signature(const mbedtls_x509_crt * child,mbedtls_x509_crt * parent,mbedtls_x509_crt_restart_ctx * rs_ctx)2122 static int x509_crt_check_signature(const mbedtls_x509_crt *child,
2123 mbedtls_x509_crt *parent,
2124 mbedtls_x509_crt_restart_ctx *rs_ctx)
2125 {
2126 size_t hash_len;
2127 unsigned char hash[MBEDTLS_MD_MAX_SIZE];
2128 #if !defined(MBEDTLS_USE_PSA_CRYPTO)
2129 const mbedtls_md_info_t *md_info;
2130 md_info = mbedtls_md_info_from_type(child->sig_md);
2131 hash_len = mbedtls_md_get_size(md_info);
2132
2133 /* Note: hash errors can happen only after an internal error */
2134 if (mbedtls_md(md_info, child->tbs.p, child->tbs.len, hash) != 0) {
2135 return -1;
2136 }
2137 #else
2138 psa_algorithm_t hash_alg = mbedtls_md_psa_alg_from_type(child->sig_md);
2139 psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
2140
2141 status = psa_hash_compute(hash_alg,
2142 child->tbs.p,
2143 child->tbs.len,
2144 hash,
2145 sizeof(hash),
2146 &hash_len);
2147 if (status != PSA_SUCCESS) {
2148 return MBEDTLS_ERR_PLATFORM_HW_ACCEL_FAILED;
2149 }
2150
2151 #endif /* MBEDTLS_USE_PSA_CRYPTO */
2152 /* Skip expensive computation on obvious mismatch */
2153 if (!mbedtls_pk_can_do(&parent->pk, child->sig_pk)) {
2154 return -1;
2155 }
2156
2157 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2158 if (rs_ctx != NULL && child->sig_pk == MBEDTLS_PK_ECDSA) {
2159 return mbedtls_pk_verify_restartable(&parent->pk,
2160 child->sig_md, hash, hash_len,
2161 child->sig.p, child->sig.len, &rs_ctx->pk);
2162 }
2163 #else
2164 (void) rs_ctx;
2165 #endif
2166
2167 return mbedtls_pk_verify_ext(child->sig_pk, child->sig_opts, &parent->pk,
2168 child->sig_md, hash, hash_len,
2169 child->sig.p, child->sig.len);
2170 }
2171
2172 /*
2173 * Check if 'parent' is a suitable parent (signing CA) for 'child'.
2174 * Return 0 if yes, -1 if not.
2175 *
2176 * top means parent is a locally-trusted certificate
2177 */
x509_crt_check_parent(const mbedtls_x509_crt * child,const mbedtls_x509_crt * parent,int top)2178 static int x509_crt_check_parent(const mbedtls_x509_crt *child,
2179 const mbedtls_x509_crt *parent,
2180 int top)
2181 {
2182 int need_ca_bit;
2183
2184 /* Parent must be the issuer */
2185 if (x509_name_cmp(&child->issuer, &parent->subject) != 0) {
2186 return -1;
2187 }
2188
2189 /* Parent must have the basicConstraints CA bit set as a general rule */
2190 need_ca_bit = 1;
2191
2192 /* Exception: v1/v2 certificates that are locally trusted. */
2193 if (top && parent->version < 3) {
2194 need_ca_bit = 0;
2195 }
2196
2197 if (need_ca_bit && !parent->ca_istrue) {
2198 return -1;
2199 }
2200
2201 if (need_ca_bit &&
2202 mbedtls_x509_crt_check_key_usage(parent, MBEDTLS_X509_KU_KEY_CERT_SIGN) != 0) {
2203 return -1;
2204 }
2205
2206 return 0;
2207 }
2208
2209 /*
2210 * Find a suitable parent for child in candidates, or return NULL.
2211 *
2212 * Here suitable is defined as:
2213 * 1. subject name matches child's issuer
2214 * 2. if necessary, the CA bit is set and key usage allows signing certs
2215 * 3. for trusted roots, the signature is correct
2216 * (for intermediates, the signature is checked and the result reported)
2217 * 4. pathlen constraints are satisfied
2218 *
2219 * If there's a suitable candidate which is also time-valid, return the first
2220 * such. Otherwise, return the first suitable candidate (or NULL if there is
2221 * none).
2222 *
2223 * The rationale for this rule is that someone could have a list of trusted
2224 * roots with two versions on the same root with different validity periods.
2225 * (At least one user reported having such a list and wanted it to just work.)
2226 * The reason we don't just require time-validity is that generally there is
2227 * only one version, and if it's expired we want the flags to state that
2228 * rather than NOT_TRUSTED, as would be the case if we required it here.
2229 *
2230 * The rationale for rule 3 (signature for trusted roots) is that users might
2231 * have two versions of the same CA with different keys in their list, and the
2232 * way we select the correct one is by checking the signature (as we don't
2233 * rely on key identifier extensions). (This is one way users might choose to
2234 * handle key rollover, another relies on self-issued certs, see [SIRO].)
2235 *
2236 * Arguments:
2237 * - [in] child: certificate for which we're looking for a parent
2238 * - [in] candidates: chained list of potential parents
2239 * - [out] r_parent: parent found (or NULL)
2240 * - [out] r_signature_is_good: 1 if child signature by parent is valid, or 0
2241 * - [in] top: 1 if candidates consists of trusted roots, ie we're at the top
2242 * of the chain, 0 otherwise
2243 * - [in] path_cnt: number of intermediates seen so far
2244 * - [in] self_cnt: number of self-signed intermediates seen so far
2245 * (will never be greater than path_cnt)
2246 * - [in-out] rs_ctx: context for restarting operations
2247 *
2248 * Return value:
2249 * - 0 on success
2250 * - MBEDTLS_ERR_ECP_IN_PROGRESS otherwise
2251 */
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)2252 static int x509_crt_find_parent_in(
2253 mbedtls_x509_crt *child,
2254 mbedtls_x509_crt *candidates,
2255 mbedtls_x509_crt **r_parent,
2256 int *r_signature_is_good,
2257 int top,
2258 unsigned path_cnt,
2259 unsigned self_cnt,
2260 mbedtls_x509_crt_restart_ctx *rs_ctx,
2261 const mbedtls_x509_time *now)
2262 {
2263 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
2264 mbedtls_x509_crt *parent, *fallback_parent;
2265 int signature_is_good = 0, fallback_signature_is_good;
2266
2267 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2268 /* did we have something in progress? */
2269 if (rs_ctx != NULL && rs_ctx->parent != NULL) {
2270 /* restore saved state */
2271 parent = rs_ctx->parent;
2272 fallback_parent = rs_ctx->fallback_parent;
2273 fallback_signature_is_good = rs_ctx->fallback_signature_is_good;
2274
2275 /* clear saved state */
2276 rs_ctx->parent = NULL;
2277 rs_ctx->fallback_parent = NULL;
2278 rs_ctx->fallback_signature_is_good = 0;
2279
2280 /* resume where we left */
2281 goto check_signature;
2282 }
2283 #endif
2284
2285 fallback_parent = NULL;
2286 fallback_signature_is_good = 0;
2287
2288 for (parent = candidates; parent != NULL; parent = parent->next) {
2289 /* basic parenting skills (name, CA bit, key usage) */
2290 if (x509_crt_check_parent(child, parent, top) != 0) {
2291 continue;
2292 }
2293
2294 /* +1 because stored max_pathlen is 1 higher that the actual value */
2295 if (parent->max_pathlen > 0 &&
2296 (size_t) parent->max_pathlen < 1 + path_cnt - self_cnt) {
2297 continue;
2298 }
2299
2300 /* Signature */
2301 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2302 check_signature:
2303 #endif
2304 ret = x509_crt_check_signature(child, parent, rs_ctx);
2305
2306 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2307 if (rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS) {
2308 /* save state */
2309 rs_ctx->parent = parent;
2310 rs_ctx->fallback_parent = fallback_parent;
2311 rs_ctx->fallback_signature_is_good = fallback_signature_is_good;
2312
2313 return ret;
2314 }
2315 #else
2316 (void) ret;
2317 #endif
2318
2319 signature_is_good = ret == 0;
2320 if (top && !signature_is_good) {
2321 continue;
2322 }
2323
2324 #if defined(MBEDTLS_HAVE_TIME_DATE)
2325 /* optional time check */
2326 if (mbedtls_x509_time_cmp(&parent->valid_to, now) < 0 || /* past */
2327 mbedtls_x509_time_cmp(&parent->valid_from, now) > 0) { /* future */
2328 if (fallback_parent == NULL) {
2329 fallback_parent = parent;
2330 fallback_signature_is_good = signature_is_good;
2331 }
2332
2333 continue;
2334 }
2335 #else
2336 ((void) now);
2337 #endif
2338
2339 *r_parent = parent;
2340 *r_signature_is_good = signature_is_good;
2341
2342 break;
2343 }
2344
2345 if (parent == NULL) {
2346 *r_parent = fallback_parent;
2347 *r_signature_is_good = fallback_signature_is_good;
2348 }
2349
2350 return 0;
2351 }
2352
2353 /*
2354 * Find a parent in trusted CAs or the provided chain, or return NULL.
2355 *
2356 * Searches in trusted CAs first, and return the first suitable parent found
2357 * (see find_parent_in() for definition of suitable).
2358 *
2359 * Arguments:
2360 * - [in] child: certificate for which we're looking for a parent, followed
2361 * by a chain of possible intermediates
2362 * - [in] trust_ca: list of locally trusted certificates
2363 * - [out] parent: parent found (or NULL)
2364 * - [out] parent_is_trusted: 1 if returned `parent` is trusted, or 0
2365 * - [out] signature_is_good: 1 if child signature by parent is valid, or 0
2366 * - [in] path_cnt: number of links in the chain so far (EE -> ... -> child)
2367 * - [in] self_cnt: number of self-signed certs in the chain so far
2368 * (will always be no greater than path_cnt)
2369 * - [in-out] rs_ctx: context for restarting operations
2370 *
2371 * Return value:
2372 * - 0 on success
2373 * - MBEDTLS_ERR_ECP_IN_PROGRESS otherwise
2374 */
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)2375 static int x509_crt_find_parent(
2376 mbedtls_x509_crt *child,
2377 mbedtls_x509_crt *trust_ca,
2378 mbedtls_x509_crt **parent,
2379 int *parent_is_trusted,
2380 int *signature_is_good,
2381 unsigned path_cnt,
2382 unsigned self_cnt,
2383 mbedtls_x509_crt_restart_ctx *rs_ctx,
2384 const mbedtls_x509_time *now)
2385 {
2386 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
2387 mbedtls_x509_crt *search_list;
2388
2389 *parent_is_trusted = 1;
2390
2391 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2392 /* restore then clear saved state if we have some stored */
2393 if (rs_ctx != NULL && rs_ctx->parent_is_trusted != -1) {
2394 *parent_is_trusted = rs_ctx->parent_is_trusted;
2395 rs_ctx->parent_is_trusted = -1;
2396 }
2397 #endif
2398
2399 while (1) {
2400 search_list = *parent_is_trusted ? trust_ca : child->next;
2401
2402 ret = x509_crt_find_parent_in(child, search_list,
2403 parent, signature_is_good,
2404 *parent_is_trusted,
2405 path_cnt, self_cnt, rs_ctx, now);
2406
2407 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2408 if (rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS) {
2409 /* save state */
2410 rs_ctx->parent_is_trusted = *parent_is_trusted;
2411 return ret;
2412 }
2413 #else
2414 (void) ret;
2415 #endif
2416
2417 /* stop here if found or already in second iteration */
2418 if (*parent != NULL || *parent_is_trusted == 0) {
2419 break;
2420 }
2421
2422 /* prepare second iteration */
2423 *parent_is_trusted = 0;
2424 }
2425
2426 /* extra precaution against mistakes in the caller */
2427 if (*parent == NULL) {
2428 *parent_is_trusted = 0;
2429 *signature_is_good = 0;
2430 }
2431
2432 return 0;
2433 }
2434
2435 /*
2436 * Check if an end-entity certificate is locally trusted
2437 *
2438 * Currently we require such certificates to be self-signed (actually only
2439 * check for self-issued as self-signatures are not checked)
2440 */
x509_crt_check_ee_locally_trusted(mbedtls_x509_crt * crt,mbedtls_x509_crt * trust_ca)2441 static int x509_crt_check_ee_locally_trusted(
2442 mbedtls_x509_crt *crt,
2443 mbedtls_x509_crt *trust_ca)
2444 {
2445 mbedtls_x509_crt *cur;
2446
2447 /* must be self-issued */
2448 if (x509_name_cmp(&crt->issuer, &crt->subject) != 0) {
2449 return -1;
2450 }
2451
2452 /* look for an exact match with trusted cert */
2453 for (cur = trust_ca; cur != NULL; cur = cur->next) {
2454 if (crt->raw.len == cur->raw.len &&
2455 memcmp(crt->raw.p, cur->raw.p, crt->raw.len) == 0) {
2456 return 0;
2457 }
2458 }
2459
2460 /* too bad */
2461 return -1;
2462 }
2463
2464 /*
2465 * Build and verify a certificate chain
2466 *
2467 * Given a peer-provided list of certificates EE, C1, ..., Cn and
2468 * a list of trusted certs R1, ... Rp, try to build and verify a chain
2469 * EE, Ci1, ... Ciq [, Rj]
2470 * such that every cert in the chain is a child of the next one,
2471 * jumping to a trusted root as early as possible.
2472 *
2473 * Verify that chain and return it with flags for all issues found.
2474 *
2475 * Special cases:
2476 * - EE == Rj -> return a one-element list containing it
2477 * - EE, Ci1, ..., Ciq cannot be continued with a trusted root
2478 * -> return that chain with NOT_TRUSTED set on Ciq
2479 *
2480 * Tests for (aspects of) this function should include at least:
2481 * - trusted EE
2482 * - EE -> trusted root
2483 * - EE -> intermediate CA -> trusted root
2484 * - if relevant: EE untrusted
2485 * - if relevant: EE -> intermediate, untrusted
2486 * with the aspect under test checked at each relevant level (EE, int, root).
2487 * For some aspects longer chains are required, but usually length 2 is
2488 * enough (but length 1 is not in general).
2489 *
2490 * Arguments:
2491 * - [in] crt: the cert list EE, C1, ..., Cn
2492 * - [in] trust_ca: the trusted list R1, ..., Rp
2493 * - [in] ca_crl, profile: as in verify_with_profile()
2494 * - [out] ver_chain: the built and verified chain
2495 * Only valid when return value is 0, may contain garbage otherwise!
2496 * Restart note: need not be the same when calling again to resume.
2497 * - [in-out] rs_ctx: context for restarting operations
2498 *
2499 * Return value:
2500 * - non-zero if the chain could not be fully built and examined
2501 * - 0 is the chain was successfully built and examined,
2502 * even if it was found to be invalid
2503 */
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)2504 static int x509_crt_verify_chain(
2505 mbedtls_x509_crt *crt,
2506 mbedtls_x509_crt *trust_ca,
2507 mbedtls_x509_crl *ca_crl,
2508 mbedtls_x509_crt_ca_cb_t f_ca_cb,
2509 void *p_ca_cb,
2510 const mbedtls_x509_crt_profile *profile,
2511 mbedtls_x509_crt_verify_chain *ver_chain,
2512 mbedtls_x509_crt_restart_ctx *rs_ctx)
2513 {
2514 /* Don't initialize any of those variables here, so that the compiler can
2515 * catch potential issues with jumping ahead when restarting */
2516 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
2517 uint32_t *flags;
2518 mbedtls_x509_crt_verify_chain_item *cur;
2519 mbedtls_x509_crt *child;
2520 mbedtls_x509_crt *parent;
2521 int parent_is_trusted;
2522 int child_is_trusted;
2523 int signature_is_good;
2524 unsigned self_cnt;
2525 mbedtls_x509_crt *cur_trust_ca = NULL;
2526 mbedtls_x509_time now;
2527
2528 #if defined(MBEDTLS_HAVE_TIME_DATE)
2529 if (mbedtls_x509_time_gmtime(mbedtls_time(NULL), &now) != 0) {
2530 return MBEDTLS_ERR_X509_FATAL_ERROR;
2531 }
2532 #endif
2533
2534 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2535 /* resume if we had an operation in progress */
2536 if (rs_ctx != NULL && rs_ctx->in_progress == x509_crt_rs_find_parent) {
2537 /* restore saved state */
2538 *ver_chain = rs_ctx->ver_chain; /* struct copy */
2539 self_cnt = rs_ctx->self_cnt;
2540
2541 /* restore derived state */
2542 cur = &ver_chain->items[ver_chain->len - 1];
2543 child = cur->crt;
2544 flags = &cur->flags;
2545
2546 goto find_parent;
2547 }
2548 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
2549
2550 child = crt;
2551 self_cnt = 0;
2552 parent_is_trusted = 0;
2553 child_is_trusted = 0;
2554
2555 while (1) {
2556 /* Add certificate to the verification chain */
2557 cur = &ver_chain->items[ver_chain->len];
2558 cur->crt = child;
2559 cur->flags = 0;
2560 ver_chain->len++;
2561 flags = &cur->flags;
2562
2563 #if defined(MBEDTLS_HAVE_TIME_DATE)
2564 /* Check time-validity (all certificates) */
2565 if (mbedtls_x509_time_cmp(&child->valid_to, &now) < 0) {
2566 *flags |= MBEDTLS_X509_BADCERT_EXPIRED;
2567 }
2568
2569 if (mbedtls_x509_time_cmp(&child->valid_from, &now) > 0) {
2570 *flags |= MBEDTLS_X509_BADCERT_FUTURE;
2571 }
2572 #endif
2573
2574 /* Stop here for trusted roots (but not for trusted EE certs) */
2575 if (child_is_trusted) {
2576 return 0;
2577 }
2578
2579 /* Check signature algorithm: MD & PK algs */
2580 if (x509_profile_check_md_alg(profile, child->sig_md) != 0) {
2581 *flags |= MBEDTLS_X509_BADCERT_BAD_MD;
2582 }
2583
2584 if (x509_profile_check_pk_alg(profile, child->sig_pk) != 0) {
2585 *flags |= MBEDTLS_X509_BADCERT_BAD_PK;
2586 }
2587
2588 /* Special case: EE certs that are locally trusted */
2589 if (ver_chain->len == 1 &&
2590 x509_crt_check_ee_locally_trusted(child, trust_ca) == 0) {
2591 return 0;
2592 }
2593
2594 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2595 find_parent:
2596 #endif
2597
2598 /* Obtain list of potential trusted signers from CA callback,
2599 * or use statically provided list. */
2600 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
2601 if (f_ca_cb != NULL) {
2602 mbedtls_x509_crt_free(ver_chain->trust_ca_cb_result);
2603 mbedtls_free(ver_chain->trust_ca_cb_result);
2604 ver_chain->trust_ca_cb_result = NULL;
2605
2606 ret = f_ca_cb(p_ca_cb, child, &ver_chain->trust_ca_cb_result);
2607 if (ret != 0) {
2608 return MBEDTLS_ERR_X509_FATAL_ERROR;
2609 }
2610
2611 cur_trust_ca = ver_chain->trust_ca_cb_result;
2612 } else
2613 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
2614 {
2615 ((void) f_ca_cb);
2616 ((void) p_ca_cb);
2617 cur_trust_ca = trust_ca;
2618 }
2619
2620 /* Look for a parent in trusted CAs or up the chain */
2621 ret = x509_crt_find_parent(child, cur_trust_ca, &parent,
2622 &parent_is_trusted, &signature_is_good,
2623 ver_chain->len - 1, self_cnt, rs_ctx,
2624 &now);
2625
2626 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
2627 if (rs_ctx != NULL && ret == MBEDTLS_ERR_ECP_IN_PROGRESS) {
2628 /* save state */
2629 rs_ctx->in_progress = x509_crt_rs_find_parent;
2630 rs_ctx->self_cnt = self_cnt;
2631 rs_ctx->ver_chain = *ver_chain; /* struct copy */
2632
2633 return ret;
2634 }
2635 #else
2636 (void) ret;
2637 #endif
2638
2639 /* No parent? We're done here */
2640 if (parent == NULL) {
2641 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
2642 return 0;
2643 }
2644
2645 /* Count intermediate self-issued (not necessarily self-signed) certs.
2646 * These can occur with some strategies for key rollover, see [SIRO],
2647 * and should be excluded from max_pathlen checks. */
2648 if (ver_chain->len != 1 &&
2649 x509_name_cmp(&child->issuer, &child->subject) == 0) {
2650 self_cnt++;
2651 }
2652
2653 /* path_cnt is 0 for the first intermediate CA,
2654 * and if parent is trusted it's not an intermediate CA */
2655 if (!parent_is_trusted &&
2656 ver_chain->len > MBEDTLS_X509_MAX_INTERMEDIATE_CA) {
2657 /* return immediately to avoid overflow the chain array */
2658 return MBEDTLS_ERR_X509_FATAL_ERROR;
2659 }
2660
2661 /* signature was checked while searching parent */
2662 if (!signature_is_good) {
2663 *flags |= MBEDTLS_X509_BADCERT_NOT_TRUSTED;
2664 }
2665
2666 /* check size of signing key */
2667 if (x509_profile_check_key(profile, &parent->pk) != 0) {
2668 *flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
2669 }
2670
2671 #if defined(MBEDTLS_X509_CRL_PARSE_C)
2672 /* Check trusted CA's CRL for the given crt */
2673 *flags |= x509_crt_verifycrl(child, parent, ca_crl, profile, &now);
2674 #else
2675 (void) ca_crl;
2676 #endif
2677
2678 /* prepare for next iteration */
2679 child = parent;
2680 parent = NULL;
2681 child_is_trusted = parent_is_trusted;
2682 signature_is_good = 0;
2683 }
2684 }
2685
2686 #ifdef _WIN32
2687 #ifdef _MSC_VER
2688 #pragma comment(lib, "ws2_32.lib")
2689 #include <winsock2.h>
2690 #include <ws2tcpip.h>
2691 #elif (defined(__MINGW32__) || defined(__MINGW64__)) && _WIN32_WINNT >= 0x0600
2692 #include <winsock2.h>
2693 #include <ws2tcpip.h>
2694 #else
2695 /* inet_pton() is not supported, fallback to software version */
2696 #define MBEDTLS_TEST_SW_INET_PTON
2697 #endif
2698 #elif defined(__sun)
2699 /* Solaris requires -lsocket -lnsl for inet_pton() */
2700 #elif defined(__has_include)
2701 #if __has_include(<sys/socket.h>)
2702 #include <sys/socket.h>
2703 #endif
2704 #if __has_include(<arpa/inet.h>)
2705 #include <arpa/inet.h>
2706 #endif
2707 #endif
2708
2709 /* Use whether or not AF_INET6 is defined to indicate whether or not to use
2710 * the platform inet_pton() or a local implementation (below). The local
2711 * implementation may be used even in cases where the platform provides
2712 * inet_pton(), e.g. when there are different includes required and/or the
2713 * platform implementation requires dependencies on additional libraries.
2714 * Specifically, Windows requires custom includes and additional link
2715 * dependencies, and Solaris requires additional link dependencies.
2716 * Also, as a coarse heuristic, use the local implementation if the compiler
2717 * does not support __has_include(), or if the definition of AF_INET6 is not
2718 * provided by headers included (or not) via __has_include() above.
2719 * MBEDTLS_TEST_SW_INET_PTON is a bypass define to force testing of this code //no-check-names
2720 * despite having a platform that has inet_pton. */
2721 #if !defined(AF_INET6) || defined(MBEDTLS_TEST_SW_INET_PTON) //no-check-names
2722 /* Definition located further below to possibly reduce compiler inlining */
2723 static int x509_inet_pton_ipv4(const char *src, void *dst);
2724
2725 #define li_cton(c, n) \
2726 (((n) = (c) - '0') <= 9 || (((n) = ((c)&0xdf) - 'A') <= 5 ? ((n) += 10) : 0))
2727
x509_inet_pton_ipv6(const char * src,void * dst)2728 static int x509_inet_pton_ipv6(const char *src, void *dst)
2729 {
2730 const unsigned char *p = (const unsigned char *) src;
2731 int nonzero_groups = 0, num_digits, zero_group_start = -1;
2732 uint16_t addr[8];
2733 do {
2734 /* note: allows excess leading 0's, e.g. 1:0002:3:... */
2735 uint16_t group = num_digits = 0;
2736 for (uint8_t digit; num_digits < 4; num_digits++) {
2737 if (li_cton(*p, digit) == 0) {
2738 break;
2739 }
2740 group = (group << 4) | digit;
2741 p++;
2742 }
2743 if (num_digits != 0) {
2744 MBEDTLS_PUT_UINT16_BE(group, addr, nonzero_groups);
2745 nonzero_groups++;
2746 if (*p == '\0') {
2747 break;
2748 } else if (*p == '.') {
2749 /* Don't accept IPv4 too early or late */
2750 if ((nonzero_groups == 0 && zero_group_start == -1) ||
2751 nonzero_groups >= 7) {
2752 break;
2753 }
2754
2755 /* Walk back to prior ':', then parse as IPv4-mapped */
2756 int steps = 4;
2757 do {
2758 p--;
2759 steps--;
2760 } while (*p != ':' && steps > 0);
2761
2762 if (*p != ':') {
2763 break;
2764 }
2765 p++;
2766 nonzero_groups--;
2767 if (x509_inet_pton_ipv4((const char *) p,
2768 addr + nonzero_groups) != 0) {
2769 break;
2770 }
2771
2772 nonzero_groups += 2;
2773 p = (const unsigned char *) "";
2774 break;
2775 } else if (*p != ':') {
2776 return -1;
2777 }
2778 } else {
2779 /* Don't accept a second zero group or an invalid delimiter */
2780 if (zero_group_start != -1 || *p != ':') {
2781 return -1;
2782 }
2783 zero_group_start = nonzero_groups;
2784
2785 /* Accept a zero group at start, but it has to be a double colon */
2786 if (zero_group_start == 0 && *++p != ':') {
2787 return -1;
2788 }
2789
2790 if (p[1] == '\0') {
2791 ++p;
2792 break;
2793 }
2794 }
2795 ++p;
2796 } while (nonzero_groups < 8);
2797
2798 if (*p != '\0') {
2799 return -1;
2800 }
2801
2802 if (zero_group_start != -1) {
2803 if (nonzero_groups > 6) {
2804 return -1;
2805 }
2806 int zero_groups = 8 - nonzero_groups;
2807 int groups_after_zero = nonzero_groups - zero_group_start;
2808
2809 /* Move the non-zero part to after the zeroes */
2810 if (groups_after_zero) {
2811 memmove(addr + zero_group_start + zero_groups,
2812 addr + zero_group_start,
2813 groups_after_zero * sizeof(*addr));
2814 }
2815 memset(addr + zero_group_start, 0, zero_groups * sizeof(*addr));
2816 } else {
2817 if (nonzero_groups != 8) {
2818 return -1;
2819 }
2820 }
2821 memcpy(dst, addr, sizeof(addr));
2822 return 0;
2823 }
2824
x509_inet_pton_ipv4(const char * src,void * dst)2825 static int x509_inet_pton_ipv4(const char *src, void *dst)
2826 {
2827 const unsigned char *p = (const unsigned char *) src;
2828 uint8_t *res = (uint8_t *) dst;
2829 uint8_t digit, num_digits = 0;
2830 uint8_t num_octets = 0;
2831 uint16_t octet;
2832
2833 do {
2834 octet = num_digits = 0;
2835 do {
2836 digit = *p - '0';
2837 if (digit > 9) {
2838 break;
2839 }
2840
2841 /* Don't allow leading zeroes. These might mean octal format,
2842 * which this implementation does not support. */
2843 if (octet == 0 && num_digits > 0) {
2844 return -1;
2845 }
2846
2847 octet = octet * 10 + digit;
2848 num_digits++;
2849 p++;
2850 } while (num_digits < 3);
2851
2852 if (octet >= 256 || num_digits > 3 || num_digits == 0) {
2853 return -1;
2854 }
2855 *res++ = (uint8_t) octet;
2856 num_octets++;
2857 } while (num_octets < 4 && *p++ == '.');
2858 return num_octets == 4 && *p == '\0' ? 0 : -1;
2859 }
2860
2861 #else
2862
x509_inet_pton_ipv6(const char * src,void * dst)2863 static int x509_inet_pton_ipv6(const char *src, void *dst)
2864 {
2865 return inet_pton(AF_INET6, src, dst) == 1 ? 0 : -1;
2866 }
2867
x509_inet_pton_ipv4(const char * src,void * dst)2868 static int x509_inet_pton_ipv4(const char *src, void *dst)
2869 {
2870 return inet_pton(AF_INET, src, dst) == 1 ? 0 : -1;
2871 }
2872
2873 #endif /* !AF_INET6 || MBEDTLS_TEST_SW_INET_PTON */ //no-check-names
2874
mbedtls_x509_crt_parse_cn_inet_pton(const char * cn,void * dst)2875 size_t mbedtls_x509_crt_parse_cn_inet_pton(const char *cn, void *dst)
2876 {
2877 return strchr(cn, ':') == NULL
2878 ? x509_inet_pton_ipv4(cn, dst) == 0 ? 4 : 0
2879 : x509_inet_pton_ipv6(cn, dst) == 0 ? 16 : 0;
2880 }
2881
2882 /*
2883 * Check for CN match
2884 */
x509_crt_check_cn(const mbedtls_x509_buf * name,const char * cn,size_t cn_len)2885 static int x509_crt_check_cn(const mbedtls_x509_buf *name,
2886 const char *cn, size_t cn_len)
2887 {
2888 /* try exact match */
2889 if (name->len == cn_len &&
2890 x509_memcasecmp(cn, name->p, cn_len) == 0) {
2891 return 0;
2892 }
2893
2894 /* try wildcard match */
2895 if (x509_check_wildcard(cn, name) == 0) {
2896 return 0;
2897 }
2898
2899 return -1;
2900 }
2901
x509_crt_check_san_ip(const mbedtls_x509_sequence * san,const char * cn,size_t cn_len)2902 static int x509_crt_check_san_ip(const mbedtls_x509_sequence *san,
2903 const char *cn, size_t cn_len)
2904 {
2905 uint32_t ip[4];
2906 cn_len = mbedtls_x509_crt_parse_cn_inet_pton(cn, ip);
2907 if (cn_len == 0) {
2908 return -1;
2909 }
2910
2911 for (const mbedtls_x509_sequence *cur = san; cur != NULL; cur = cur->next) {
2912 const unsigned char san_type = (unsigned char) cur->buf.tag &
2913 MBEDTLS_ASN1_TAG_VALUE_MASK;
2914 if (san_type == MBEDTLS_X509_SAN_IP_ADDRESS &&
2915 cur->buf.len == cn_len && memcmp(cur->buf.p, ip, cn_len) == 0) {
2916 return 0;
2917 }
2918 }
2919
2920 return -1;
2921 }
2922
x509_crt_check_san_uri(const mbedtls_x509_sequence * san,const char * cn,size_t cn_len)2923 static int x509_crt_check_san_uri(const mbedtls_x509_sequence *san,
2924 const char *cn, size_t cn_len)
2925 {
2926 for (const mbedtls_x509_sequence *cur = san; cur != NULL; cur = cur->next) {
2927 const unsigned char san_type = (unsigned char) cur->buf.tag &
2928 MBEDTLS_ASN1_TAG_VALUE_MASK;
2929 if (san_type == MBEDTLS_X509_SAN_UNIFORM_RESOURCE_IDENTIFIER &&
2930 cur->buf.len == cn_len && memcmp(cur->buf.p, cn, cn_len) == 0) {
2931 return 0;
2932 }
2933 }
2934
2935 return -1;
2936 }
2937
2938 /*
2939 * Check for SAN match, see RFC 5280 Section 4.2.1.6
2940 */
x509_crt_check_san(const mbedtls_x509_sequence * san,const char * cn,size_t cn_len)2941 static int x509_crt_check_san(const mbedtls_x509_sequence *san,
2942 const char *cn, size_t cn_len)
2943 {
2944 int san_ip = 0;
2945 int san_uri = 0;
2946 /* Prioritize DNS name over other subtypes due to popularity */
2947 for (const mbedtls_x509_sequence *cur = san; cur != NULL; cur = cur->next) {
2948 switch ((unsigned char) cur->buf.tag & MBEDTLS_ASN1_TAG_VALUE_MASK) {
2949 case MBEDTLS_X509_SAN_DNS_NAME:
2950 if (x509_crt_check_cn(&cur->buf, cn, cn_len) == 0) {
2951 return 0;
2952 }
2953 break;
2954 case MBEDTLS_X509_SAN_IP_ADDRESS:
2955 san_ip = 1;
2956 break;
2957 case MBEDTLS_X509_SAN_UNIFORM_RESOURCE_IDENTIFIER:
2958 san_uri = 1;
2959 break;
2960 /* (We may handle other types here later.) */
2961 default: /* Unrecognized type */
2962 break;
2963 }
2964 }
2965 if (san_ip) {
2966 if (x509_crt_check_san_ip(san, cn, cn_len) == 0) {
2967 return 0;
2968 }
2969 }
2970 if (san_uri) {
2971 if (x509_crt_check_san_uri(san, cn, cn_len) == 0) {
2972 return 0;
2973 }
2974 }
2975
2976 return -1;
2977 }
2978
2979 /*
2980 * Verify the requested CN - only call this if cn is not NULL!
2981 */
x509_crt_verify_name(const mbedtls_x509_crt * crt,const char * cn,uint32_t * flags)2982 static void x509_crt_verify_name(const mbedtls_x509_crt *crt,
2983 const char *cn,
2984 uint32_t *flags)
2985 {
2986 const mbedtls_x509_name *name;
2987 size_t cn_len = strlen(cn);
2988
2989 if (crt->ext_types & MBEDTLS_X509_EXT_SUBJECT_ALT_NAME) {
2990 if (x509_crt_check_san(&crt->subject_alt_names, cn, cn_len) == 0) {
2991 return;
2992 }
2993 } else {
2994 for (name = &crt->subject; name != NULL; name = name->next) {
2995 if (MBEDTLS_OID_CMP(MBEDTLS_OID_AT_CN, &name->oid) == 0 &&
2996 x509_crt_check_cn(&name->val, cn, cn_len) == 0) {
2997 return;
2998 }
2999 }
3000
3001 }
3002
3003 *flags |= MBEDTLS_X509_BADCERT_CN_MISMATCH;
3004 }
3005
3006 /*
3007 * Merge the flags for all certs in the chain, after calling callback
3008 */
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)3009 static int x509_crt_merge_flags_with_cb(
3010 uint32_t *flags,
3011 const mbedtls_x509_crt_verify_chain *ver_chain,
3012 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3013 void *p_vrfy)
3014 {
3015 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
3016 unsigned i;
3017 uint32_t cur_flags;
3018 const mbedtls_x509_crt_verify_chain_item *cur;
3019
3020 for (i = ver_chain->len; i != 0; --i) {
3021 cur = &ver_chain->items[i-1];
3022 cur_flags = cur->flags;
3023
3024 if (NULL != f_vrfy) {
3025 if ((ret = f_vrfy(p_vrfy, cur->crt, (int) i-1, &cur_flags)) != 0) {
3026 return ret;
3027 }
3028 }
3029
3030 *flags |= cur_flags;
3031 }
3032
3033 return 0;
3034 }
3035
3036 /*
3037 * Verify the certificate validity, with profile, restartable version
3038 *
3039 * This function:
3040 * - checks the requested CN (if any)
3041 * - checks the type and size of the EE cert's key,
3042 * as that isn't done as part of chain building/verification currently
3043 * - builds and verifies the chain
3044 * - then calls the callback and merges the flags
3045 *
3046 * The parameters pairs `trust_ca`, `ca_crl` and `f_ca_cb`, `p_ca_cb`
3047 * are mutually exclusive: If `f_ca_cb != NULL`, it will be used by the
3048 * verification routine to search for trusted signers, and CRLs will
3049 * be disabled. Otherwise, `trust_ca` will be used as the static list
3050 * of trusted signers, and `ca_crl` will be use as the static list
3051 * of CRLs.
3052 */
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)3053 static int x509_crt_verify_restartable_ca_cb(mbedtls_x509_crt *crt,
3054 mbedtls_x509_crt *trust_ca,
3055 mbedtls_x509_crl *ca_crl,
3056 mbedtls_x509_crt_ca_cb_t f_ca_cb,
3057 void *p_ca_cb,
3058 const mbedtls_x509_crt_profile *profile,
3059 const char *cn, uint32_t *flags,
3060 int (*f_vrfy)(void *,
3061 mbedtls_x509_crt *,
3062 int,
3063 uint32_t *),
3064 void *p_vrfy,
3065 mbedtls_x509_crt_restart_ctx *rs_ctx)
3066 {
3067 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
3068 mbedtls_pk_type_t pk_type;
3069 mbedtls_x509_crt_verify_chain ver_chain;
3070 uint32_t ee_flags;
3071
3072 *flags = 0;
3073 ee_flags = 0;
3074 x509_crt_verify_chain_reset(&ver_chain);
3075
3076 if (profile == NULL) {
3077 ret = MBEDTLS_ERR_X509_BAD_INPUT_DATA;
3078 goto exit;
3079 }
3080
3081 /* check name if requested */
3082 if (cn != NULL) {
3083 x509_crt_verify_name(crt, cn, &ee_flags);
3084 }
3085
3086 /* Check the type and size of the key */
3087 pk_type = mbedtls_pk_get_type(&crt->pk);
3088
3089 if (x509_profile_check_pk_alg(profile, pk_type) != 0) {
3090 ee_flags |= MBEDTLS_X509_BADCERT_BAD_PK;
3091 }
3092
3093 if (x509_profile_check_key(profile, &crt->pk) != 0) {
3094 ee_flags |= MBEDTLS_X509_BADCERT_BAD_KEY;
3095 }
3096
3097 /* Check the chain */
3098 ret = x509_crt_verify_chain(crt, trust_ca, ca_crl,
3099 f_ca_cb, p_ca_cb, profile,
3100 &ver_chain, rs_ctx);
3101
3102 if (ret != 0) {
3103 goto exit;
3104 }
3105
3106 /* Merge end-entity flags */
3107 ver_chain.items[0].flags |= ee_flags;
3108
3109 /* Build final flags, calling callback on the way if any */
3110 ret = x509_crt_merge_flags_with_cb(flags, &ver_chain, f_vrfy, p_vrfy);
3111
3112 exit:
3113
3114 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
3115 mbedtls_x509_crt_free(ver_chain.trust_ca_cb_result);
3116 mbedtls_free(ver_chain.trust_ca_cb_result);
3117 ver_chain.trust_ca_cb_result = NULL;
3118 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
3119
3120 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
3121 if (rs_ctx != NULL && ret != MBEDTLS_ERR_ECP_IN_PROGRESS) {
3122 mbedtls_x509_crt_restart_free(rs_ctx);
3123 }
3124 #endif
3125
3126 /* prevent misuse of the vrfy callback - VERIFY_FAILED would be ignored by
3127 * the SSL module for authmode optional, but non-zero return from the
3128 * callback means a fatal error so it shouldn't be ignored */
3129 if (ret == MBEDTLS_ERR_X509_CERT_VERIFY_FAILED) {
3130 ret = MBEDTLS_ERR_X509_FATAL_ERROR;
3131 }
3132
3133 if (ret != 0) {
3134 *flags = (uint32_t) -1;
3135 return ret;
3136 }
3137
3138 if (*flags != 0) {
3139 return MBEDTLS_ERR_X509_CERT_VERIFY_FAILED;
3140 }
3141
3142 return 0;
3143 }
3144
3145
3146 /*
3147 * Verify the certificate validity (default profile, not restartable)
3148 */
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)3149 int mbedtls_x509_crt_verify(mbedtls_x509_crt *crt,
3150 mbedtls_x509_crt *trust_ca,
3151 mbedtls_x509_crl *ca_crl,
3152 const char *cn, uint32_t *flags,
3153 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3154 void *p_vrfy)
3155 {
3156 return x509_crt_verify_restartable_ca_cb(crt, trust_ca, ca_crl,
3157 NULL, NULL,
3158 &mbedtls_x509_crt_profile_default,
3159 cn, flags,
3160 f_vrfy, p_vrfy, NULL);
3161 }
3162
3163 /*
3164 * Verify the certificate validity (user-chosen profile, not restartable)
3165 */
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)3166 int mbedtls_x509_crt_verify_with_profile(mbedtls_x509_crt *crt,
3167 mbedtls_x509_crt *trust_ca,
3168 mbedtls_x509_crl *ca_crl,
3169 const mbedtls_x509_crt_profile *profile,
3170 const char *cn, uint32_t *flags,
3171 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3172 void *p_vrfy)
3173 {
3174 return x509_crt_verify_restartable_ca_cb(crt, trust_ca, ca_crl,
3175 NULL, NULL,
3176 profile, cn, flags,
3177 f_vrfy, p_vrfy, NULL);
3178 }
3179
3180 #if defined(MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK)
3181 /*
3182 * Verify the certificate validity (user-chosen profile, CA callback,
3183 * not restartable).
3184 */
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)3185 int mbedtls_x509_crt_verify_with_ca_cb(mbedtls_x509_crt *crt,
3186 mbedtls_x509_crt_ca_cb_t f_ca_cb,
3187 void *p_ca_cb,
3188 const mbedtls_x509_crt_profile *profile,
3189 const char *cn, uint32_t *flags,
3190 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3191 void *p_vrfy)
3192 {
3193 return x509_crt_verify_restartable_ca_cb(crt, NULL, NULL,
3194 f_ca_cb, p_ca_cb,
3195 profile, cn, flags,
3196 f_vrfy, p_vrfy, NULL);
3197 }
3198 #endif /* MBEDTLS_X509_TRUSTED_CERTIFICATE_CALLBACK */
3199
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)3200 int mbedtls_x509_crt_verify_restartable(mbedtls_x509_crt *crt,
3201 mbedtls_x509_crt *trust_ca,
3202 mbedtls_x509_crl *ca_crl,
3203 const mbedtls_x509_crt_profile *profile,
3204 const char *cn, uint32_t *flags,
3205 int (*f_vrfy)(void *, mbedtls_x509_crt *, int, uint32_t *),
3206 void *p_vrfy,
3207 mbedtls_x509_crt_restart_ctx *rs_ctx)
3208 {
3209 return x509_crt_verify_restartable_ca_cb(crt, trust_ca, ca_crl,
3210 NULL, NULL,
3211 profile, cn, flags,
3212 f_vrfy, p_vrfy, rs_ctx);
3213 }
3214
3215
3216 /*
3217 * Initialize a certificate chain
3218 */
mbedtls_x509_crt_init(mbedtls_x509_crt * crt)3219 void mbedtls_x509_crt_init(mbedtls_x509_crt *crt)
3220 {
3221 memset(crt, 0, sizeof(mbedtls_x509_crt));
3222 }
3223
3224 /*
3225 * Unallocate all certificate data
3226 */
mbedtls_x509_crt_free(mbedtls_x509_crt * crt)3227 void mbedtls_x509_crt_free(mbedtls_x509_crt *crt)
3228 {
3229 mbedtls_x509_crt *cert_cur = crt;
3230 mbedtls_x509_crt *cert_prv;
3231
3232 while (cert_cur != NULL) {
3233 mbedtls_pk_free(&cert_cur->pk);
3234
3235 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
3236 mbedtls_free(cert_cur->sig_opts);
3237 #endif
3238
3239 mbedtls_asn1_free_named_data_list_shallow(cert_cur->issuer.next);
3240 mbedtls_asn1_free_named_data_list_shallow(cert_cur->subject.next);
3241 mbedtls_asn1_sequence_free(cert_cur->ext_key_usage.next);
3242 mbedtls_asn1_sequence_free(cert_cur->subject_alt_names.next);
3243 mbedtls_asn1_sequence_free(cert_cur->certificate_policies.next);
3244 mbedtls_asn1_sequence_free(cert_cur->authority_key_id.authorityCertIssuer.next);
3245
3246 if (cert_cur->raw.p != NULL && cert_cur->own_buffer) {
3247 mbedtls_zeroize_and_free(cert_cur->raw.p, cert_cur->raw.len);
3248 }
3249
3250 cert_prv = cert_cur;
3251 cert_cur = cert_cur->next;
3252
3253 mbedtls_platform_zeroize(cert_prv, sizeof(mbedtls_x509_crt));
3254 if (cert_prv != crt) {
3255 mbedtls_free(cert_prv);
3256 }
3257 }
3258 }
3259
3260 #if defined(MBEDTLS_ECDSA_C) && defined(MBEDTLS_ECP_RESTARTABLE)
3261 /*
3262 * Initialize a restart context
3263 */
mbedtls_x509_crt_restart_init(mbedtls_x509_crt_restart_ctx * ctx)3264 void mbedtls_x509_crt_restart_init(mbedtls_x509_crt_restart_ctx *ctx)
3265 {
3266 mbedtls_pk_restart_init(&ctx->pk);
3267
3268 ctx->parent = NULL;
3269 ctx->fallback_parent = NULL;
3270 ctx->fallback_signature_is_good = 0;
3271
3272 ctx->parent_is_trusted = -1;
3273
3274 ctx->in_progress = x509_crt_rs_none;
3275 ctx->self_cnt = 0;
3276 x509_crt_verify_chain_reset(&ctx->ver_chain);
3277 }
3278
3279 /*
3280 * Free the components of a restart context
3281 */
mbedtls_x509_crt_restart_free(mbedtls_x509_crt_restart_ctx * ctx)3282 void mbedtls_x509_crt_restart_free(mbedtls_x509_crt_restart_ctx *ctx)
3283 {
3284 if (ctx == NULL) {
3285 return;
3286 }
3287
3288 mbedtls_pk_restart_free(&ctx->pk);
3289 mbedtls_x509_crt_restart_init(ctx);
3290 }
3291 #endif /* MBEDTLS_ECDSA_C && MBEDTLS_ECP_RESTARTABLE */
3292
mbedtls_x509_crt_get_ca_istrue(const mbedtls_x509_crt * crt)3293 int mbedtls_x509_crt_get_ca_istrue(const mbedtls_x509_crt *crt)
3294 {
3295 if ((crt->ext_types & MBEDTLS_X509_EXT_BASIC_CONSTRAINTS) != 0) {
3296 return crt->MBEDTLS_PRIVATE(ca_istrue);
3297 }
3298 return MBEDTLS_ERR_X509_INVALID_EXTENSIONS;
3299 }
3300
3301 #endif /* MBEDTLS_X509_CRT_PARSE_C */
3302
