1/*
2 * Public Key layer for parsing key files and structures
3 *
4 * Copyright The Mbed TLS Contributors
5 * SPDX-License-Identifier: Apache-2.0
6 *
7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
8 * not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 */
19
20#include "common.h"
21
22#if defined(MBEDTLS_PK_PARSE_C)
23
24#include "mbedtls/pk.h"
25#include "mbedtls/asn1.h"
26#include "mbedtls/oid.h"
27#include "mbedtls/platform_util.h"
28#include "mbedtls/error.h"
29
30#include <string.h>
31
32#if defined(MBEDTLS_RSA_C)
33#include "mbedtls/rsa.h"
34#endif
35#if defined(MBEDTLS_ECP_C)
36#include "mbedtls/ecp.h"
37#endif
38#if defined(MBEDTLS_ECDSA_C)
39#include "mbedtls/ecdsa.h"
40#endif
41#if defined(MBEDTLS_PEM_PARSE_C)
42#include "mbedtls/pem.h"
43#endif
44#if defined(MBEDTLS_PKCS5_C)
45#include "mbedtls/pkcs5.h"
46#endif
47#if defined(MBEDTLS_PKCS12_C)
48#include "mbedtls/pkcs12.h"
49#endif
50
51#include "mbedtls/platform.h"
52
53/* Parameter validation macros based on platform_util.h */
54#define PK_VALIDATE_RET(cond) \
55 MBEDTLS_INTERNAL_VALIDATE_RET(cond, MBEDTLS_ERR_PK_BAD_INPUT_DATA)
56#define PK_VALIDATE(cond) \
57 MBEDTLS_INTERNAL_VALIDATE(cond)
58
59#if defined(MBEDTLS_FS_IO)
60/*
61 * Load all data from a file into a given buffer.
62 *
63 * The file is expected to contain either PEM or DER encoded data.
64 * A terminating null byte is always appended. It is included in the announced
65 * length only if the data looks like it is PEM encoded.
66 */
67int mbedtls_pk_load_file(const char *path, unsigned char **buf, size_t *n)
68{
69 FILE *f;
70 long size;
71
72 PK_VALIDATE_RET(path != NULL);
73 PK_VALIDATE_RET(buf != NULL);
74 PK_VALIDATE_RET(n != NULL);
75
76 if ((f = fopen(path, "rb")) == NULL) {
77 return MBEDTLS_ERR_PK_FILE_IO_ERROR;
78 }
79
80 fseek(f, 0, SEEK_END);
81 if ((size = ftell(f)) == -1) {
82 fclose(f);
83 return MBEDTLS_ERR_PK_FILE_IO_ERROR;
84 }
85 fseek(f, 0, SEEK_SET);
86
87 *n = (size_t) size;
88
89 if (*n + 1 == 0 ||
90 (*buf = mbedtls_calloc(1, *n + 1)) == NULL) {
91 fclose(f);
92 return MBEDTLS_ERR_PK_ALLOC_FAILED;
93 }
94
95 if (fread(*buf, 1, *n, f) != *n) {
96 fclose(f);
97
98 mbedtls_platform_zeroize(*buf, *n);
99 mbedtls_free(*buf);
100
101 return MBEDTLS_ERR_PK_FILE_IO_ERROR;
102 }
103
104 fclose(f);
105
106 (*buf)[*n] = '\0';
107
108 if (strstr((const char *) *buf, "-----BEGIN ") != NULL) {
109 ++*n;
110 }
111
112 return 0;
113}
114
115/*
116 * Load and parse a private key
117 */
118int mbedtls_pk_parse_keyfile(mbedtls_pk_context *ctx,
119 const char *path, const char *pwd)
120{
121 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
122 size_t n;
123 unsigned char *buf;
124
125 PK_VALIDATE_RET(ctx != NULL);
126 PK_VALIDATE_RET(path != NULL);
127
128 if ((ret = mbedtls_pk_load_file(path, &buf, &n)) != 0) {
129 return ret;
130 }
131
132 if (pwd == NULL) {
133 ret = mbedtls_pk_parse_key(ctx, buf, n, NULL, 0);
134 } else {
135 ret = mbedtls_pk_parse_key(ctx, buf, n,
136 (const unsigned char *) pwd, strlen(pwd));
137 }
138
139 mbedtls_platform_zeroize(buf, n);
140 mbedtls_free(buf);
141
142 return ret;
143}
144
145/*
146 * Load and parse a public key
147 */
148int mbedtls_pk_parse_public_keyfile(mbedtls_pk_context *ctx, const char *path)
149{
150 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
151 size_t n;
152 unsigned char *buf;
153
154 PK_VALIDATE_RET(ctx != NULL);
155 PK_VALIDATE_RET(path != NULL);
156
157 if ((ret = mbedtls_pk_load_file(path, &buf, &n)) != 0) {
158 return ret;
159 }
160
161 ret = mbedtls_pk_parse_public_key(ctx, buf, n);
162
163 mbedtls_platform_zeroize(buf, n);
164 mbedtls_free(buf);
165
166 return ret;
167}
168#endif /* MBEDTLS_FS_IO */
169
170#if defined(MBEDTLS_ECP_C)
171/* Minimally parse an ECParameters buffer to and mbedtls_asn1_buf
172 *
173 * ECParameters ::= CHOICE {
174 * namedCurve OBJECT IDENTIFIER
175 * specifiedCurve SpecifiedECDomain -- = SEQUENCE { ... }
176 * -- implicitCurve NULL
177 * }
178 */
179static int pk_get_ecparams(unsigned char **p, const unsigned char *end,
180 mbedtls_asn1_buf *params)
181{
182 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
183
184 if (end - *p < 1) {
185 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
186 MBEDTLS_ERR_ASN1_OUT_OF_DATA);
187 }
188
189 /* Tag may be either OID or SEQUENCE */
190 params->tag = **p;
191 if (params->tag != MBEDTLS_ASN1_OID
192#if defined(MBEDTLS_PK_PARSE_EC_EXTENDED)
193 && params->tag != (MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)
194#endif
195 ) {
196 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
197 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
198 }
199
200 if ((ret = mbedtls_asn1_get_tag(p, end, &params->len, params->tag)) != 0) {
201 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
202 }
203
204 params->p = *p;
205 *p += params->len;
206
207 if (*p != end) {
208 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
209 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
210 }
211
212 return 0;
213}
214
215#if defined(MBEDTLS_PK_PARSE_EC_EXTENDED)
216/*
217 * Parse a SpecifiedECDomain (SEC 1 C.2) and (mostly) fill the group with it.
218 * WARNING: the resulting group should only be used with
219 * pk_group_id_from_specified(), since its base point may not be set correctly
220 * if it was encoded compressed.
221 *
222 * SpecifiedECDomain ::= SEQUENCE {
223 * version SpecifiedECDomainVersion(ecdpVer1 | ecdpVer2 | ecdpVer3, ...),
224 * fieldID FieldID {{FieldTypes}},
225 * curve Curve,
226 * base ECPoint,
227 * order INTEGER,
228 * cofactor INTEGER OPTIONAL,
229 * hash HashAlgorithm OPTIONAL,
230 * ...
231 * }
232 *
233 * We only support prime-field as field type, and ignore hash and cofactor.
234 */
235static int pk_group_from_specified(const mbedtls_asn1_buf *params, mbedtls_ecp_group *grp)
236{
237 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
238 unsigned char *p = params->p;
239 const unsigned char * const end = params->p + params->len;
240 const unsigned char *end_field, *end_curve;
241 size_t len;
242 int ver;
243
244 /* SpecifiedECDomainVersion ::= INTEGER { 1, 2, 3 } */
245 if ((ret = mbedtls_asn1_get_int(&p, end, &ver)) != 0) {
246 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
247 }
248
249 if (ver < 1 || ver > 3) {
250 return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
251 }
252
253 /*
254 * FieldID { FIELD-ID:IOSet } ::= SEQUENCE { -- Finite field
255 * fieldType FIELD-ID.&id({IOSet}),
256 * parameters FIELD-ID.&Type({IOSet}{@fieldType})
257 * }
258 */
259 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
260 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
261 return ret;
262 }
263
264 end_field = p + len;
265
266 /*
267 * FIELD-ID ::= TYPE-IDENTIFIER
268 * FieldTypes FIELD-ID ::= {
269 * { Prime-p IDENTIFIED BY prime-field } |
270 * { Characteristic-two IDENTIFIED BY characteristic-two-field }
271 * }
272 * prime-field OBJECT IDENTIFIER ::= { id-fieldType 1 }
273 */
274 if ((ret = mbedtls_asn1_get_tag(&p, end_field, &len, MBEDTLS_ASN1_OID)) != 0) {
275 return ret;
276 }
277
278 if (len != MBEDTLS_OID_SIZE(MBEDTLS_OID_ANSI_X9_62_PRIME_FIELD) ||
279 memcmp(p, MBEDTLS_OID_ANSI_X9_62_PRIME_FIELD, len) != 0) {
280 return MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE;
281 }
282
283 p += len;
284
285 /* Prime-p ::= INTEGER -- Field of size p. */
286 if ((ret = mbedtls_asn1_get_mpi(&p, end_field, &grp->P)) != 0) {
287 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
288 }
289
290 grp->pbits = mbedtls_mpi_bitlen(&grp->P);
291
292 if (p != end_field) {
293 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
294 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
295 }
296
297 /*
298 * Curve ::= SEQUENCE {
299 * a FieldElement,
300 * b FieldElement,
301 * seed BIT STRING OPTIONAL
302 * -- Shall be present if used in SpecifiedECDomain
303 * -- with version equal to ecdpVer2 or ecdpVer3
304 * }
305 */
306 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
307 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
308 return ret;
309 }
310
311 end_curve = p + len;
312
313 /*
314 * FieldElement ::= OCTET STRING
315 * containing an integer in the case of a prime field
316 */
317 if ((ret = mbedtls_asn1_get_tag(&p, end_curve, &len, MBEDTLS_ASN1_OCTET_STRING)) != 0 ||
318 (ret = mbedtls_mpi_read_binary(&grp->A, p, len)) != 0) {
319 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
320 }
321
322 p += len;
323
324 if ((ret = mbedtls_asn1_get_tag(&p, end_curve, &len, MBEDTLS_ASN1_OCTET_STRING)) != 0 ||
325 (ret = mbedtls_mpi_read_binary(&grp->B, p, len)) != 0) {
326 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
327 }
328
329 p += len;
330
331 /* Ignore seed BIT STRING OPTIONAL */
332 if ((ret = mbedtls_asn1_get_tag(&p, end_curve, &len, MBEDTLS_ASN1_BIT_STRING)) == 0) {
333 p += len;
334 }
335
336 if (p != end_curve) {
337 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
338 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
339 }
340
341 /*
342 * ECPoint ::= OCTET STRING
343 */
344 if ((ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING)) != 0) {
345 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
346 }
347
348 if ((ret = mbedtls_ecp_point_read_binary(grp, &grp->G,
349 (const unsigned char *) p, len)) != 0) {
350 /*
351 * If we can't read the point because it's compressed, cheat by
352 * reading only the X coordinate and the parity bit of Y.
353 */
354 if (ret != MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE ||
355 (p[0] != 0x02 && p[0] != 0x03) ||
356 len != mbedtls_mpi_size(&grp->P) + 1 ||
357 mbedtls_mpi_read_binary(&grp->G.X, p + 1, len - 1) != 0 ||
358 mbedtls_mpi_lset(&grp->G.Y, p[0] - 2) != 0 ||
359 mbedtls_mpi_lset(&grp->G.Z, 1) != 0) {
360 return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
361 }
362 }
363
364 p += len;
365
366 /*
367 * order INTEGER
368 */
369 if ((ret = mbedtls_asn1_get_mpi(&p, end, &grp->N)) != 0) {
370 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
371 }
372
373 grp->nbits = mbedtls_mpi_bitlen(&grp->N);
374
375 /*
376 * Allow optional elements by purposefully not enforcing p == end here.
377 */
378
379 return 0;
380}
381
382/*
383 * Find the group id associated with an (almost filled) group as generated by
384 * pk_group_from_specified(), or return an error if unknown.
385 */
386static int pk_group_id_from_group(const mbedtls_ecp_group *grp, mbedtls_ecp_group_id *grp_id)
387{
388 int ret = 0;
389 mbedtls_ecp_group ref;
390 const mbedtls_ecp_group_id *id;
391
392 mbedtls_ecp_group_init(&ref);
393
394 for (id = mbedtls_ecp_grp_id_list(); *id != MBEDTLS_ECP_DP_NONE; id++) {
395 /* Load the group associated to that id */
396 mbedtls_ecp_group_free(&ref);
397 MBEDTLS_MPI_CHK(mbedtls_ecp_group_load(&ref, *id));
398
399 /* Compare to the group we were given, starting with easy tests */
400 if (grp->pbits == ref.pbits && grp->nbits == ref.nbits &&
401 mbedtls_mpi_cmp_mpi(&grp->P, &ref.P) == 0 &&
402 mbedtls_mpi_cmp_mpi(&grp->A, &ref.A) == 0 &&
403 mbedtls_mpi_cmp_mpi(&grp->B, &ref.B) == 0 &&
404 mbedtls_mpi_cmp_mpi(&grp->N, &ref.N) == 0 &&
405 mbedtls_mpi_cmp_mpi(&grp->G.X, &ref.G.X) == 0 &&
406 mbedtls_mpi_cmp_mpi(&grp->G.Z, &ref.G.Z) == 0 &&
407 /* For Y we may only know the parity bit, so compare only that */
408 mbedtls_mpi_get_bit(&grp->G.Y, 0) == mbedtls_mpi_get_bit(&ref.G.Y, 0)) {
409 break;
410 }
411
412 }
413
414cleanup:
415 mbedtls_ecp_group_free(&ref);
416
417 *grp_id = *id;
418
419 if (ret == 0 && *id == MBEDTLS_ECP_DP_NONE) {
420 ret = MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE;
421 }
422
423 return ret;
424}
425
426/*
427 * Parse a SpecifiedECDomain (SEC 1 C.2) and find the associated group ID
428 */
429static int pk_group_id_from_specified(const mbedtls_asn1_buf *params,
430 mbedtls_ecp_group_id *grp_id)
431{
432 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
433 mbedtls_ecp_group grp;
434
435 mbedtls_ecp_group_init(&grp);
436
437 if ((ret = pk_group_from_specified(params, &grp)) != 0) {
438 goto cleanup;
439 }
440
441 ret = pk_group_id_from_group(&grp, grp_id);
442
443cleanup:
444 mbedtls_ecp_group_free(&grp);
445
446 return ret;
447}
448#endif /* MBEDTLS_PK_PARSE_EC_EXTENDED */
449
450/*
451 * Use EC parameters to initialise an EC group
452 *
453 * ECParameters ::= CHOICE {
454 * namedCurve OBJECT IDENTIFIER
455 * specifiedCurve SpecifiedECDomain -- = SEQUENCE { ... }
456 * -- implicitCurve NULL
457 */
458static int pk_use_ecparams(const mbedtls_asn1_buf *params, mbedtls_ecp_group *grp)
459{
460 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
461 mbedtls_ecp_group_id grp_id;
462
463 if (params->tag == MBEDTLS_ASN1_OID) {
464 if (mbedtls_oid_get_ec_grp(params, &grp_id) != 0) {
465 return MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE;
466 }
467 } else {
468#if defined(MBEDTLS_PK_PARSE_EC_EXTENDED)
469 if ((ret = pk_group_id_from_specified(params, &grp_id)) != 0) {
470 return ret;
471 }
472#else
473 return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
474#endif
475 }
476
477 /*
478 * grp may already be initialized; if so, make sure IDs match
479 */
480 if (grp->id != MBEDTLS_ECP_DP_NONE && grp->id != grp_id) {
481 return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
482 }
483
484 if ((ret = mbedtls_ecp_group_load(grp, grp_id)) != 0) {
485 return ret;
486 }
487
488 return 0;
489}
490
491/*
492 * EC public key is an EC point
493 *
494 * The caller is responsible for clearing the structure upon failure if
495 * desired. Take care to pass along the possible ECP_FEATURE_UNAVAILABLE
496 * return code of mbedtls_ecp_point_read_binary() and leave p in a usable state.
497 */
498static int pk_get_ecpubkey(unsigned char **p, const unsigned char *end,
499 mbedtls_ecp_keypair *key)
500{
501 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
502
503 if ((ret = mbedtls_ecp_point_read_binary(&key->grp, &key->Q,
504 (const unsigned char *) *p, end - *p)) == 0) {
505 ret = mbedtls_ecp_check_pubkey(&key->grp, &key->Q);
506 }
507
508 /*
509 * We know mbedtls_ecp_point_read_binary consumed all bytes or failed
510 */
511 *p = (unsigned char *) end;
512
513 return ret;
514}
515#endif /* MBEDTLS_ECP_C */
516
517#if defined(MBEDTLS_RSA_C)
518/*
519 * RSAPublicKey ::= SEQUENCE {
520 * modulus INTEGER, -- n
521 * publicExponent INTEGER -- e
522 * }
523 */
524static int pk_get_rsapubkey(unsigned char **p,
525 const unsigned char *end,
526 mbedtls_rsa_context *rsa)
527{
528 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
529 size_t len;
530
531 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
532 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
533 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_PUBKEY, ret);
534 }
535
536 if (*p + len != end) {
537 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_PUBKEY,
538 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
539 }
540
541 /* Import N */
542 if ((ret = mbedtls_asn1_get_tag(p, end, &len, MBEDTLS_ASN1_INTEGER)) != 0) {
543 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_PUBKEY, ret);
544 }
545
546 if ((ret = mbedtls_rsa_import_raw(rsa, *p, len, NULL, 0, NULL, 0,
547 NULL, 0, NULL, 0)) != 0) {
548 return MBEDTLS_ERR_PK_INVALID_PUBKEY;
549 }
550
551 *p += len;
552
553 /* Import E */
554 if ((ret = mbedtls_asn1_get_tag(p, end, &len, MBEDTLS_ASN1_INTEGER)) != 0) {
555 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_PUBKEY, ret);
556 }
557
558 if ((ret = mbedtls_rsa_import_raw(rsa, NULL, 0, NULL, 0, NULL, 0,
559 NULL, 0, *p, len)) != 0) {
560 return MBEDTLS_ERR_PK_INVALID_PUBKEY;
561 }
562
563 *p += len;
564
565 if (mbedtls_rsa_complete(rsa) != 0 ||
566 mbedtls_rsa_check_pubkey(rsa) != 0) {
567 return MBEDTLS_ERR_PK_INVALID_PUBKEY;
568 }
569
570 if (*p != end) {
571 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_PUBKEY,
572 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
573 }
574
575 return 0;
576}
577#endif /* MBEDTLS_RSA_C */
578
579/* Get a PK algorithm identifier
580 *
581 * AlgorithmIdentifier ::= SEQUENCE {
582 * algorithm OBJECT IDENTIFIER,
583 * parameters ANY DEFINED BY algorithm OPTIONAL }
584 */
585static int pk_get_pk_alg(unsigned char **p,
586 const unsigned char *end,
587 mbedtls_pk_type_t *pk_alg, mbedtls_asn1_buf *params)
588{
589 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
590 mbedtls_asn1_buf alg_oid;
591
592 memset(params, 0, sizeof(mbedtls_asn1_buf));
593
594 if ((ret = mbedtls_asn1_get_alg(p, end, &alg_oid, params)) != 0) {
595 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_ALG, ret);
596 }
597
598 if (mbedtls_oid_get_pk_alg(&alg_oid, pk_alg) != 0) {
599 return MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
600 }
601
602 /*
603 * No parameters with RSA (only for EC)
604 */
605 if (*pk_alg == MBEDTLS_PK_RSA &&
606 ((params->tag != MBEDTLS_ASN1_NULL && params->tag != 0) ||
607 params->len != 0)) {
608 return MBEDTLS_ERR_PK_INVALID_ALG;
609 }
610
611 return 0;
612}
613
614/*
615 * SubjectPublicKeyInfo ::= SEQUENCE {
616 * algorithm AlgorithmIdentifier,
617 * subjectPublicKey BIT STRING }
618 */
619int mbedtls_pk_parse_subpubkey(unsigned char **p, const unsigned char *end,
620 mbedtls_pk_context *pk)
621{
622 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
623 size_t len;
624 mbedtls_asn1_buf alg_params;
625 mbedtls_pk_type_t pk_alg = MBEDTLS_PK_NONE;
626 const mbedtls_pk_info_t *pk_info;
627
628 PK_VALIDATE_RET(p != NULL);
629 PK_VALIDATE_RET(*p != NULL);
630 PK_VALIDATE_RET(end != NULL);
631 PK_VALIDATE_RET(pk != NULL);
632
633 if ((ret = mbedtls_asn1_get_tag(p, end, &len,
634 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
635 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
636 }
637
638 end = *p + len;
639
640 if ((ret = pk_get_pk_alg(p, end, &pk_alg, &alg_params)) != 0) {
641 return ret;
642 }
643
644 if ((ret = mbedtls_asn1_get_bitstring_null(p, end, &len)) != 0) {
645 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_PUBKEY, ret);
646 }
647
648 if (*p + len != end) {
649 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_PUBKEY,
650 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
651 }
652
653 if ((pk_info = mbedtls_pk_info_from_type(pk_alg)) == NULL) {
654 return MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
655 }
656
657 if ((ret = mbedtls_pk_setup(pk, pk_info)) != 0) {
658 return ret;
659 }
660
661#if defined(MBEDTLS_RSA_C)
662 if (pk_alg == MBEDTLS_PK_RSA) {
663 ret = pk_get_rsapubkey(p, end, mbedtls_pk_rsa(*pk));
664 } else
665#endif /* MBEDTLS_RSA_C */
666#if defined(MBEDTLS_ECP_C)
667 if (pk_alg == MBEDTLS_PK_ECKEY_DH || pk_alg == MBEDTLS_PK_ECKEY) {
668 ret = pk_use_ecparams(&alg_params, &mbedtls_pk_ec(*pk)->grp);
669 if (ret == 0) {
670 ret = pk_get_ecpubkey(p, end, mbedtls_pk_ec(*pk));
671 }
672 } else
673#endif /* MBEDTLS_ECP_C */
674 ret = MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
675
676 if (ret == 0 && *p != end) {
677 ret = MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_PUBKEY,
678 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
679 }
680
681 if (ret != 0) {
682 mbedtls_pk_free(pk);
683 }
684
685 return ret;
686}
687
688#if defined(MBEDTLS_RSA_C)
689/*
690 * Wrapper around mbedtls_asn1_get_mpi() that rejects zero.
691 *
692 * The value zero is:
693 * - never a valid value for an RSA parameter
694 * - interpreted as "omitted, please reconstruct" by mbedtls_rsa_complete().
695 *
696 * Since values can't be omitted in PKCS#1, passing a zero value to
697 * rsa_complete() would be incorrect, so reject zero values early.
698 */
699static int asn1_get_nonzero_mpi(unsigned char **p,
700 const unsigned char *end,
701 mbedtls_mpi *X)
702{
703 int ret;
704
705 ret = mbedtls_asn1_get_mpi(p, end, X);
706 if (ret != 0) {
707 return ret;
708 }
709
710 if (mbedtls_mpi_cmp_int(X, 0) == 0) {
711 return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
712 }
713
714 return 0;
715}
716
717/*
718 * Parse a PKCS#1 encoded private RSA key
719 */
720static int pk_parse_key_pkcs1_der(mbedtls_rsa_context *rsa,
721 const unsigned char *key,
722 size_t keylen)
723{
724 int ret, version;
725 size_t len;
726 unsigned char *p, *end;
727
728 mbedtls_mpi T;
729 mbedtls_mpi_init(&T);
730
731 p = (unsigned char *) key;
732 end = p + keylen;
733
734 /*
735 * This function parses the RSAPrivateKey (PKCS#1)
736 *
737 * RSAPrivateKey ::= SEQUENCE {
738 * version Version,
739 * modulus INTEGER, -- n
740 * publicExponent INTEGER, -- e
741 * privateExponent INTEGER, -- d
742 * prime1 INTEGER, -- p
743 * prime2 INTEGER, -- q
744 * exponent1 INTEGER, -- d mod (p-1)
745 * exponent2 INTEGER, -- d mod (q-1)
746 * coefficient INTEGER, -- (inverse of q) mod p
747 * otherPrimeInfos OtherPrimeInfos OPTIONAL
748 * }
749 */
750 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
751 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
752 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
753 }
754
755 end = p + len;
756
757 if ((ret = mbedtls_asn1_get_int(&p, end, &version)) != 0) {
758 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
759 }
760
761 if (version != 0) {
762 return MBEDTLS_ERR_PK_KEY_INVALID_VERSION;
763 }
764
765 /* Import N */
766 if ((ret = asn1_get_nonzero_mpi(&p, end, &T)) != 0 ||
767 (ret = mbedtls_rsa_import(rsa, &T, NULL, NULL,
768 NULL, NULL)) != 0) {
769 goto cleanup;
770 }
771
772 /* Import E */
773 if ((ret = asn1_get_nonzero_mpi(&p, end, &T)) != 0 ||
774 (ret = mbedtls_rsa_import(rsa, NULL, NULL, NULL,
775 NULL, &T)) != 0) {
776 goto cleanup;
777 }
778
779 /* Import D */
780 if ((ret = asn1_get_nonzero_mpi(&p, end, &T)) != 0 ||
781 (ret = mbedtls_rsa_import(rsa, NULL, NULL, NULL,
782 &T, NULL)) != 0) {
783 goto cleanup;
784 }
785
786 /* Import P */
787 if ((ret = asn1_get_nonzero_mpi(&p, end, &T)) != 0 ||
788 (ret = mbedtls_rsa_import(rsa, NULL, &T, NULL,
789 NULL, NULL)) != 0) {
790 goto cleanup;
791 }
792
793 /* Import Q */
794 if ((ret = asn1_get_nonzero_mpi(&p, end, &T)) != 0 ||
795 (ret = mbedtls_rsa_import(rsa, NULL, NULL, &T,
796 NULL, NULL)) != 0) {
797 goto cleanup;
798 }
799
800#if !defined(MBEDTLS_RSA_NO_CRT) && !defined(MBEDTLS_RSA_ALT)
801 /*
802 * The RSA CRT parameters DP, DQ and QP are nominally redundant, in
803 * that they can be easily recomputed from D, P and Q. However by
804 * parsing them from the PKCS1 structure it is possible to avoid
805 * recalculating them which both reduces the overhead of loading
806 * RSA private keys into memory and also avoids side channels which
807 * can arise when computing those values, since all of D, P, and Q
808 * are secret. See https://eprint.iacr.org/2020/055 for a
809 * description of one such attack.
810 */
811
812 /* Import DP */
813 if ((ret = asn1_get_nonzero_mpi(&p, end, &T)) != 0 ||
814 (ret = mbedtls_mpi_copy(&rsa->DP, &T)) != 0) {
815 goto cleanup;
816 }
817
818 /* Import DQ */
819 if ((ret = asn1_get_nonzero_mpi(&p, end, &T)) != 0 ||
820 (ret = mbedtls_mpi_copy(&rsa->DQ, &T)) != 0) {
821 goto cleanup;
822 }
823
824 /* Import QP */
825 if ((ret = asn1_get_nonzero_mpi(&p, end, &T)) != 0 ||
826 (ret = mbedtls_mpi_copy(&rsa->QP, &T)) != 0) {
827 goto cleanup;
828 }
829
830#else
831 /* Verify existence of the CRT params */
832 if ((ret = asn1_get_nonzero_mpi(&p, end, &T)) != 0 ||
833 (ret = asn1_get_nonzero_mpi(&p, end, &T)) != 0 ||
834 (ret = asn1_get_nonzero_mpi(&p, end, &T)) != 0) {
835 goto cleanup;
836 }
837#endif
838
839 /* rsa_complete() doesn't complete anything with the default
840 * implementation but is still called:
841 * - for the benefit of alternative implementation that may want to
842 * pre-compute stuff beyond what's provided (eg Montgomery factors)
843 * - as is also sanity-checks the key
844 *
845 * Furthermore, we also check the public part for consistency with
846 * mbedtls_pk_parse_pubkey(), as it includes size minima for example.
847 */
848 if ((ret = mbedtls_rsa_complete(rsa)) != 0 ||
849 (ret = mbedtls_rsa_check_pubkey(rsa)) != 0) {
850 goto cleanup;
851 }
852
853 if (p != end) {
854 ret = MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
855 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
856 }
857
858cleanup:
859
860 mbedtls_mpi_free(&T);
861
862 if (ret != 0) {
863 /* Wrap error code if it's coming from a lower level */
864 if ((ret & 0xff80) == 0) {
865 ret = MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
866 } else {
867 ret = MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
868 }
869
870 mbedtls_rsa_free(rsa);
871 }
872
873 return ret;
874}
875#endif /* MBEDTLS_RSA_C */
876
877#if defined(MBEDTLS_ECP_C)
878/*
879 * Parse a SEC1 encoded private EC key
880 */
881static int pk_parse_key_sec1_der(mbedtls_ecp_keypair *eck,
882 const unsigned char *key,
883 size_t keylen)
884{
885 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
886 int version, pubkey_done;
887 size_t len;
888 mbedtls_asn1_buf params;
889 unsigned char *p = (unsigned char *) key;
890 unsigned char *end = p + keylen;
891 unsigned char *end2;
892
893 /*
894 * RFC 5915, or SEC1 Appendix C.4
895 *
896 * ECPrivateKey ::= SEQUENCE {
897 * version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
898 * privateKey OCTET STRING,
899 * parameters [0] ECParameters {{ NamedCurve }} OPTIONAL,
900 * publicKey [1] BIT STRING OPTIONAL
901 * }
902 */
903 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
904 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
905 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
906 }
907
908 end = p + len;
909
910 if ((ret = mbedtls_asn1_get_int(&p, end, &version)) != 0) {
911 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
912 }
913
914 if (version != 1) {
915 return MBEDTLS_ERR_PK_KEY_INVALID_VERSION;
916 }
917
918 if ((ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING)) != 0) {
919 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
920 }
921
922 if ((ret = mbedtls_mpi_read_binary(&eck->d, p, len)) != 0) {
923 mbedtls_ecp_keypair_free(eck);
924 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
925 }
926
927 p += len;
928
929 pubkey_done = 0;
930 if (p != end) {
931 /*
932 * Is 'parameters' present?
933 */
934 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
935 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED |
936 0)) == 0) {
937 if ((ret = pk_get_ecparams(&p, p + len, &params)) != 0 ||
938 (ret = pk_use_ecparams(&params, &eck->grp)) != 0) {
939 mbedtls_ecp_keypair_free(eck);
940 return ret;
941 }
942 } else if (ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
943 mbedtls_ecp_keypair_free(eck);
944 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
945 }
946 }
947
948 if (p != end) {
949 /*
950 * Is 'publickey' present? If not, or if we can't read it (eg because it
951 * is compressed), create it from the private key.
952 */
953 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
954 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED |
955 1)) == 0) {
956 end2 = p + len;
957
958 if ((ret = mbedtls_asn1_get_bitstring_null(&p, end2, &len)) != 0) {
959 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
960 }
961
962 if (p + len != end2) {
963 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
964 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
965 }
966
967 if ((ret = pk_get_ecpubkey(&p, end2, eck)) == 0) {
968 pubkey_done = 1;
969 } else {
970 /*
971 * The only acceptable failure mode of pk_get_ecpubkey() above
972 * is if the point format is not recognized.
973 */
974 if (ret != MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE) {
975 return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
976 }
977 }
978 } else if (ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
979 mbedtls_ecp_keypair_free(eck);
980 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
981 }
982 }
983
984 if (!pubkey_done &&
985 (ret = mbedtls_ecp_mul(&eck->grp, &eck->Q, &eck->d, &eck->grp.G,
986 NULL, NULL)) != 0) {
987 mbedtls_ecp_keypair_free(eck);
988 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
989 }
990
991 if ((ret = mbedtls_ecp_check_privkey(&eck->grp, &eck->d)) != 0) {
992 mbedtls_ecp_keypair_free(eck);
993 return ret;
994 }
995
996 return 0;
997}
998#endif /* MBEDTLS_ECP_C */
999
1000/*
1001 * Parse an unencrypted PKCS#8 encoded private key
1002 *
1003 * Notes:
1004 *
1005 * - This function does not own the key buffer. It is the
1006 * responsibility of the caller to take care of zeroizing
1007 * and freeing it after use.
1008 *
1009 * - The function is responsible for freeing the provided
1010 * PK context on failure.
1011 *
1012 */
1013static int pk_parse_key_pkcs8_unencrypted_der(
1014 mbedtls_pk_context *pk,
1015 const unsigned char *key,
1016 size_t keylen)
1017{
1018 int ret, version;
1019 size_t len;
1020 mbedtls_asn1_buf params;
1021 unsigned char *p = (unsigned char *) key;
1022 unsigned char *end = p + keylen;
1023 mbedtls_pk_type_t pk_alg = MBEDTLS_PK_NONE;
1024 const mbedtls_pk_info_t *pk_info;
1025
1026 /*
1027 * This function parses the PrivateKeyInfo object (PKCS#8 v1.2 = RFC 5208)
1028 *
1029 * PrivateKeyInfo ::= SEQUENCE {
1030 * version Version,
1031 * privateKeyAlgorithm PrivateKeyAlgorithmIdentifier,
1032 * privateKey PrivateKey,
1033 * attributes [0] IMPLICIT Attributes OPTIONAL }
1034 *
1035 * Version ::= INTEGER
1036 * PrivateKeyAlgorithmIdentifier ::= AlgorithmIdentifier
1037 * PrivateKey ::= OCTET STRING
1038 *
1039 * The PrivateKey OCTET STRING is a SEC1 ECPrivateKey
1040 */
1041
1042 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
1043 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
1044 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
1045 }
1046
1047 end = p + len;
1048
1049 if ((ret = mbedtls_asn1_get_int(&p, end, &version)) != 0) {
1050 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
1051 }
1052
1053 if (version != 0) {
1054 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_VERSION, ret);
1055 }
1056
1057 if ((ret = pk_get_pk_alg(&p, end, &pk_alg, &params)) != 0) {
1058 return ret;
1059 }
1060
1061 if ((ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING)) != 0) {
1062 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
1063 }
1064
1065 if (len < 1) {
1066 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT,
1067 MBEDTLS_ERR_ASN1_OUT_OF_DATA);
1068 }
1069
1070 if ((pk_info = mbedtls_pk_info_from_type(pk_alg)) == NULL) {
1071 return MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
1072 }
1073
1074 if ((ret = mbedtls_pk_setup(pk, pk_info)) != 0) {
1075 return ret;
1076 }
1077
1078#if defined(MBEDTLS_RSA_C)
1079 if (pk_alg == MBEDTLS_PK_RSA) {
1080 if ((ret = pk_parse_key_pkcs1_der(mbedtls_pk_rsa(*pk), p, len)) != 0) {
1081 mbedtls_pk_free(pk);
1082 return ret;
1083 }
1084 } else
1085#endif /* MBEDTLS_RSA_C */
1086#if defined(MBEDTLS_ECP_C)
1087 if (pk_alg == MBEDTLS_PK_ECKEY || pk_alg == MBEDTLS_PK_ECKEY_DH) {
1088 if ((ret = pk_use_ecparams(&params, &mbedtls_pk_ec(*pk)->grp)) != 0 ||
1089 (ret = pk_parse_key_sec1_der(mbedtls_pk_ec(*pk), p, len)) != 0) {
1090 mbedtls_pk_free(pk);
1091 return ret;
1092 }
1093 } else
1094#endif /* MBEDTLS_ECP_C */
1095 return MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
1096
1097 return 0;
1098}
1099
1100/*
1101 * Parse an encrypted PKCS#8 encoded private key
1102 *
1103 * To save space, the decryption happens in-place on the given key buffer.
1104 * Also, while this function may modify the keybuffer, it doesn't own it,
1105 * and instead it is the responsibility of the caller to zeroize and properly
1106 * free it after use.
1107 *
1108 */
1109#if defined(MBEDTLS_PKCS12_C) || defined(MBEDTLS_PKCS5_C)
1110static int pk_parse_key_pkcs8_encrypted_der(
1111 mbedtls_pk_context *pk,
1112 unsigned char *key, size_t keylen,
1113 const unsigned char *pwd, size_t pwdlen)
1114{
1115 int ret, decrypted = 0;
1116 size_t len;
1117 unsigned char *buf;
1118 unsigned char *p, *end;
1119 mbedtls_asn1_buf pbe_alg_oid, pbe_params;
1120#if defined(MBEDTLS_PKCS12_C)
1121 mbedtls_cipher_type_t cipher_alg;
1122 mbedtls_md_type_t md_alg;
1123#endif
1124
1125 p = key;
1126 end = p + keylen;
1127
1128 if (pwdlen == 0) {
1129 return MBEDTLS_ERR_PK_PASSWORD_REQUIRED;
1130 }
1131
1132 /*
1133 * This function parses the EncryptedPrivateKeyInfo object (PKCS#8)
1134 *
1135 * EncryptedPrivateKeyInfo ::= SEQUENCE {
1136 * encryptionAlgorithm EncryptionAlgorithmIdentifier,
1137 * encryptedData EncryptedData
1138 * }
1139 *
1140 * EncryptionAlgorithmIdentifier ::= AlgorithmIdentifier
1141 *
1142 * EncryptedData ::= OCTET STRING
1143 *
1144 * The EncryptedData OCTET STRING is a PKCS#8 PrivateKeyInfo
1145 *
1146 */
1147 if ((ret = mbedtls_asn1_get_tag(&p, end, &len,
1148 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) != 0) {
1149 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
1150 }
1151
1152 end = p + len;
1153
1154 if ((ret = mbedtls_asn1_get_alg(&p, end, &pbe_alg_oid, &pbe_params)) != 0) {
1155 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
1156 }
1157
1158 if ((ret = mbedtls_asn1_get_tag(&p, end, &len, MBEDTLS_ASN1_OCTET_STRING)) != 0) {
1159 return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_KEY_INVALID_FORMAT, ret);
1160 }
1161
1162 buf = p;
1163
1164 /*
1165 * Decrypt EncryptedData with appropriate PBE
1166 */
1167#if defined(MBEDTLS_PKCS12_C)
1168 if (mbedtls_oid_get_pkcs12_pbe_alg(&pbe_alg_oid, &md_alg, &cipher_alg) == 0) {
1169 if ((ret = mbedtls_pkcs12_pbe(&pbe_params, MBEDTLS_PKCS12_PBE_DECRYPT,
1170 cipher_alg, md_alg,
1171 pwd, pwdlen, p, len, buf)) != 0) {
1172 if (ret == MBEDTLS_ERR_PKCS12_PASSWORD_MISMATCH) {
1173 return MBEDTLS_ERR_PK_PASSWORD_MISMATCH;
1174 }
1175
1176 return ret;
1177 }
1178
1179 decrypted = 1;
1180 } else if (MBEDTLS_OID_CMP(MBEDTLS_OID_PKCS12_PBE_SHA1_RC4_128, &pbe_alg_oid) == 0) {
1181 if ((ret = mbedtls_pkcs12_pbe_sha1_rc4_128(&pbe_params,
1182 MBEDTLS_PKCS12_PBE_DECRYPT,
1183 pwd, pwdlen,
1184 p, len, buf)) != 0) {
1185 return ret;
1186 }
1187
1188 // Best guess for password mismatch when using RC4. If first tag is
1189 // not MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE
1190 //
1191 if (*buf != (MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) {
1192 return MBEDTLS_ERR_PK_PASSWORD_MISMATCH;
1193 }
1194
1195 decrypted = 1;
1196 } else
1197#endif /* MBEDTLS_PKCS12_C */
1198#if defined(MBEDTLS_PKCS5_C)
1199 if (MBEDTLS_OID_CMP(MBEDTLS_OID_PKCS5_PBES2, &pbe_alg_oid) == 0) {
1200 if ((ret = mbedtls_pkcs5_pbes2(&pbe_params, MBEDTLS_PKCS5_DECRYPT, pwd, pwdlen,
1201 p, len, buf)) != 0) {
1202 if (ret == MBEDTLS_ERR_PKCS5_PASSWORD_MISMATCH) {
1203 return MBEDTLS_ERR_PK_PASSWORD_MISMATCH;
1204 }
1205
1206 return ret;
1207 }
1208
1209 decrypted = 1;
1210 } else
1211#endif /* MBEDTLS_PKCS5_C */
1212 {
1213 ((void) pwd);
1214 }
1215
1216 if (decrypted == 0) {
1217 return MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE;
1218 }
1219
1220 return pk_parse_key_pkcs8_unencrypted_der(pk, buf, len);
1221}
1222#endif /* MBEDTLS_PKCS12_C || MBEDTLS_PKCS5_C */
1223
1224/*
1225 * Parse a private key
1226 */
1227int mbedtls_pk_parse_key(mbedtls_pk_context *pk,
1228 const unsigned char *key, size_t keylen,
1229 const unsigned char *pwd, size_t pwdlen)
1230{
1231 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1232 const mbedtls_pk_info_t *pk_info;
1233#if defined(MBEDTLS_PEM_PARSE_C)
1234 size_t len;
1235 mbedtls_pem_context pem;
1236#endif
1237
1238 (void) pk_info;
1239
1240 PK_VALIDATE_RET(pk != NULL);
1241 if (keylen == 0) {
1242 return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
1243 }
1244 PK_VALIDATE_RET(key != NULL);
1245
1246#if defined(MBEDTLS_PEM_PARSE_C)
1247 mbedtls_pem_init(&pem);
1248
1249#if defined(MBEDTLS_RSA_C)
1250 /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
1251 if (key[keylen - 1] != '\0') {
1252 ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
1253 } else {
1254 ret = mbedtls_pem_read_buffer(&pem,
1255 "-----BEGIN RSA PRIVATE KEY-----",
1256 "-----END RSA PRIVATE KEY-----",
1257 key, pwd, pwdlen, &len);
1258 }
1259
1260 if (ret == 0) {
1261 pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_RSA);
1262 if ((ret = mbedtls_pk_setup(pk, pk_info)) != 0 ||
1263 (ret = pk_parse_key_pkcs1_der(mbedtls_pk_rsa(*pk),
1264 pem.buf, pem.buflen)) != 0) {
1265 mbedtls_pk_free(pk);
1266 }
1267
1268 mbedtls_pem_free(&pem);
1269 return ret;
1270 } else if (ret == MBEDTLS_ERR_PEM_PASSWORD_MISMATCH) {
1271 return MBEDTLS_ERR_PK_PASSWORD_MISMATCH;
1272 } else if (ret == MBEDTLS_ERR_PEM_PASSWORD_REQUIRED) {
1273 return MBEDTLS_ERR_PK_PASSWORD_REQUIRED;
1274 } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
1275 return ret;
1276 }
1277#endif /* MBEDTLS_RSA_C */
1278
1279#if defined(MBEDTLS_ECP_C)
1280 /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
1281 if (key[keylen - 1] != '\0') {
1282 ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
1283 } else {
1284 ret = mbedtls_pem_read_buffer(&pem,
1285 "-----BEGIN EC PRIVATE KEY-----",
1286 "-----END EC PRIVATE KEY-----",
1287 key, pwd, pwdlen, &len);
1288 }
1289 if (ret == 0) {
1290 pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY);
1291
1292 if ((ret = mbedtls_pk_setup(pk, pk_info)) != 0 ||
1293 (ret = pk_parse_key_sec1_der(mbedtls_pk_ec(*pk),
1294 pem.buf, pem.buflen)) != 0) {
1295 mbedtls_pk_free(pk);
1296 }
1297
1298 mbedtls_pem_free(&pem);
1299 return ret;
1300 } else if (ret == MBEDTLS_ERR_PEM_PASSWORD_MISMATCH) {
1301 return MBEDTLS_ERR_PK_PASSWORD_MISMATCH;
1302 } else if (ret == MBEDTLS_ERR_PEM_PASSWORD_REQUIRED) {
1303 return MBEDTLS_ERR_PK_PASSWORD_REQUIRED;
1304 } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
1305 return ret;
1306 }
1307#endif /* MBEDTLS_ECP_C */
1308
1309 /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
1310 if (key[keylen - 1] != '\0') {
1311 ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
1312 } else {
1313 ret = mbedtls_pem_read_buffer(&pem,
1314 "-----BEGIN PRIVATE KEY-----",
1315 "-----END PRIVATE KEY-----",
1316 key, NULL, 0, &len);
1317 }
1318 if (ret == 0) {
1319 if ((ret = pk_parse_key_pkcs8_unencrypted_der(pk,
1320 pem.buf, pem.buflen)) != 0) {
1321 mbedtls_pk_free(pk);
1322 }
1323
1324 mbedtls_pem_free(&pem);
1325 return ret;
1326 } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
1327 return ret;
1328 }
1329
1330#if defined(MBEDTLS_PKCS12_C) || defined(MBEDTLS_PKCS5_C)
1331 /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
1332 if (key[keylen - 1] != '\0') {
1333 ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
1334 } else {
1335 ret = mbedtls_pem_read_buffer(&pem,
1336 "-----BEGIN ENCRYPTED PRIVATE KEY-----",
1337 "-----END ENCRYPTED PRIVATE KEY-----",
1338 key, NULL, 0, &len);
1339 }
1340 if (ret == 0) {
1341 if ((ret = pk_parse_key_pkcs8_encrypted_der(pk,
1342 pem.buf, pem.buflen,
1343 pwd, pwdlen)) != 0) {
1344 mbedtls_pk_free(pk);
1345 }
1346
1347 mbedtls_pem_free(&pem);
1348 return ret;
1349 } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
1350 return ret;
1351 }
1352#endif /* MBEDTLS_PKCS12_C || MBEDTLS_PKCS5_C */
1353#else
1354 ((void) pwd);
1355 ((void) pwdlen);
1356#endif /* MBEDTLS_PEM_PARSE_C */
1357
1358 /*
1359 * At this point we only know it's not a PEM formatted key. Could be any
1360 * of the known DER encoded private key formats
1361 *
1362 * We try the different DER format parsers to see if one passes without
1363 * error
1364 */
1365#if defined(MBEDTLS_PKCS12_C) || defined(MBEDTLS_PKCS5_C)
1366 {
1367 unsigned char *key_copy;
1368
1369 if ((key_copy = mbedtls_calloc(1, keylen)) == NULL) {
1370 return MBEDTLS_ERR_PK_ALLOC_FAILED;
1371 }
1372
1373 memcpy(key_copy, key, keylen);
1374
1375 ret = pk_parse_key_pkcs8_encrypted_der(pk, key_copy, keylen,
1376 pwd, pwdlen);
1377
1378 mbedtls_platform_zeroize(key_copy, keylen);
1379 mbedtls_free(key_copy);
1380 }
1381
1382 if (ret == 0) {
1383 return 0;
1384 }
1385
1386 mbedtls_pk_free(pk);
1387 mbedtls_pk_init(pk);
1388
1389 if (ret == MBEDTLS_ERR_PK_PASSWORD_MISMATCH) {
1390 return ret;
1391 }
1392#endif /* MBEDTLS_PKCS12_C || MBEDTLS_PKCS5_C */
1393
1394 ret = pk_parse_key_pkcs8_unencrypted_der(pk, key, keylen);
1395 if (ret == 0) {
1396 return 0;
1397 }
1398
1399 mbedtls_pk_free(pk);
1400 mbedtls_pk_init(pk);
1401
1402#if defined(MBEDTLS_RSA_C)
1403
1404 pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_RSA);
1405 if (mbedtls_pk_setup(pk, pk_info) == 0 &&
1406 pk_parse_key_pkcs1_der(mbedtls_pk_rsa(*pk), key, keylen) == 0) {
1407 return 0;
1408 }
1409
1410 mbedtls_pk_free(pk);
1411 mbedtls_pk_init(pk);
1412#endif /* MBEDTLS_RSA_C */
1413
1414#if defined(MBEDTLS_ECP_C)
1415 pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_ECKEY);
1416 if (mbedtls_pk_setup(pk, pk_info) == 0 &&
1417 pk_parse_key_sec1_der(mbedtls_pk_ec(*pk),
1418 key, keylen) == 0) {
1419 return 0;
1420 }
1421 mbedtls_pk_free(pk);
1422#endif /* MBEDTLS_ECP_C */
1423
1424 /* If MBEDTLS_RSA_C is defined but MBEDTLS_ECP_C isn't,
1425 * it is ok to leave the PK context initialized but not
1426 * freed: It is the caller's responsibility to call pk_init()
1427 * before calling this function, and to call pk_free()
1428 * when it fails. If MBEDTLS_ECP_C is defined but MBEDTLS_RSA_C
1429 * isn't, this leads to mbedtls_pk_free() being called
1430 * twice, once here and once by the caller, but this is
1431 * also ok and in line with the mbedtls_pk_free() calls
1432 * on failed PEM parsing attempts. */
1433
1434 return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
1435}
1436
1437/*
1438 * Parse a public key
1439 */
1440int mbedtls_pk_parse_public_key(mbedtls_pk_context *ctx,
1441 const unsigned char *key, size_t keylen)
1442{
1443 int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
1444 unsigned char *p;
1445#if defined(MBEDTLS_RSA_C)
1446 const mbedtls_pk_info_t *pk_info;
1447#endif
1448#if defined(MBEDTLS_PEM_PARSE_C)
1449 size_t len;
1450 mbedtls_pem_context pem;
1451#endif
1452
1453 PK_VALIDATE_RET(ctx != NULL);
1454 if (keylen == 0) {
1455 return MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
1456 }
1457 PK_VALIDATE_RET(key != NULL || keylen == 0);
1458
1459#if defined(MBEDTLS_PEM_PARSE_C)
1460 mbedtls_pem_init(&pem);
1461#if defined(MBEDTLS_RSA_C)
1462 /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
1463 if (key[keylen - 1] != '\0') {
1464 ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
1465 } else {
1466 ret = mbedtls_pem_read_buffer(&pem,
1467 "-----BEGIN RSA PUBLIC KEY-----",
1468 "-----END RSA PUBLIC KEY-----",
1469 key, NULL, 0, &len);
1470 }
1471
1472 if (ret == 0) {
1473 p = pem.buf;
1474 if ((pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_RSA)) == NULL) {
1475 mbedtls_pem_free(&pem);
1476 return MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
1477 }
1478
1479 if ((ret = mbedtls_pk_setup(ctx, pk_info)) != 0) {
1480 mbedtls_pem_free(&pem);
1481 return ret;
1482 }
1483
1484 if ((ret = pk_get_rsapubkey(&p, p + pem.buflen, mbedtls_pk_rsa(*ctx))) != 0) {
1485 mbedtls_pk_free(ctx);
1486 }
1487
1488 mbedtls_pem_free(&pem);
1489 return ret;
1490 } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
1491 mbedtls_pem_free(&pem);
1492 return ret;
1493 }
1494#endif /* MBEDTLS_RSA_C */
1495
1496 /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
1497 if (key[keylen - 1] != '\0') {
1498 ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
1499 } else {
1500 ret = mbedtls_pem_read_buffer(&pem,
1501 "-----BEGIN PUBLIC KEY-----",
1502 "-----END PUBLIC KEY-----",
1503 key, NULL, 0, &len);
1504 }
1505
1506 if (ret == 0) {
1507 /*
1508 * Was PEM encoded
1509 */
1510 p = pem.buf;
1511
1512 ret = mbedtls_pk_parse_subpubkey(&p, p + pem.buflen, ctx);
1513 mbedtls_pem_free(&pem);
1514 return ret;
1515 } else if (ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT) {
1516 mbedtls_pem_free(&pem);
1517 return ret;
1518 }
1519 mbedtls_pem_free(&pem);
1520#endif /* MBEDTLS_PEM_PARSE_C */
1521
1522#if defined(MBEDTLS_RSA_C)
1523 if ((pk_info = mbedtls_pk_info_from_type(MBEDTLS_PK_RSA)) == NULL) {
1524 return MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
1525 }
1526
1527 if ((ret = mbedtls_pk_setup(ctx, pk_info)) != 0) {
1528 return ret;
1529 }
1530
1531 p = (unsigned char *) key;
1532 ret = pk_get_rsapubkey(&p, p + keylen, mbedtls_pk_rsa(*ctx));
1533 if (ret == 0) {
1534 return ret;
1535 }
1536 mbedtls_pk_free(ctx);
1537 if (ret != (MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PK_INVALID_PUBKEY,
1538 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG))) {
1539 return ret;
1540 }
1541#endif /* MBEDTLS_RSA_C */
1542 p = (unsigned char *) key;
1543
1544 ret = mbedtls_pk_parse_subpubkey(&p, p + keylen, ctx);
1545
1546 return ret;
1547}
1548
1549#endif /* MBEDTLS_PK_PARSE_C */
1550