1 /*
2 * Public Key layer for parsing key files and structures
3 *
4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
5 * SPDX-License-Identifier: GPL-2.0
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License along
18 * with this program; if not, write to the Free Software Foundation, Inc.,
19 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * This file is part of mbed TLS (https://tls.mbed.org)
22 */
23
24 #if !defined(MBEDTLS_CONFIG_FILE)
25 #include "mbedtls/config.h"
26 #else
27 #include MBEDTLS_CONFIG_FILE
28 #endif
29
30 #if defined(MBEDTLS_PK_PARSE_C)
31
32 #include "mbedtls/pk.h"
33 #include "mbedtls/asn1.h"
34 #include "mbedtls/oid.h"
35 #include "mbedtls/platform_util.h"
36
37 #include <string.h>
38
39 #if defined(MBEDTLS_RSA_C)
40 #include "mbedtls/rsa.h"
41 #endif
42 #if defined(MBEDTLS_ECP_C)
43 #include "mbedtls/ecp.h"
44 #endif
45 #if defined(MBEDTLS_ECDSA_C)
46 #include "mbedtls/ecdsa.h"
47 #endif
48 #if defined(MBEDTLS_PEM_PARSE_C)
49 #include "mbedtls/pem.h"
50 #endif
51 #if defined(MBEDTLS_PKCS5_C)
52 #include "mbedtls/pkcs5.h"
53 #endif
54 #if defined(MBEDTLS_PKCS12_C)
55 #include "mbedtls/pkcs12.h"
56 #endif
57
58 #if defined(MBEDTLS_PLATFORM_C)
59 #include "mbedtls/platform.h"
60 #else
61 #include <stdlib.h>
62 #define mbedtls_calloc calloc
63 #define mbedtls_free free
64 #endif
65
66 /* Parameter validation macros based on platform_util.h */
67 #define PK_VALIDATE_RET( cond ) \
68 MBEDTLS_INTERNAL_VALIDATE_RET( cond, MBEDTLS_ERR_PK_BAD_INPUT_DATA )
69 #define PK_VALIDATE( cond ) \
70 MBEDTLS_INTERNAL_VALIDATE( cond )
71
72 #if defined(MBEDTLS_FS_IO)
73 /*
74 * Load all data from a file into a given buffer.
75 *
76 * The file is expected to contain either PEM or DER encoded data.
77 * A terminating null byte is always appended. It is included in the announced
78 * length only if the data looks like it is PEM encoded.
79 */
mbedtls_pk_load_file(const char * path,unsigned char ** buf,size_t * n)80 int mbedtls_pk_load_file( const char *path, unsigned char **buf, size_t *n )
81 {
82 FILE *f;
83 long size;
84
85 PK_VALIDATE_RET( path != NULL );
86 PK_VALIDATE_RET( buf != NULL );
87 PK_VALIDATE_RET( n != NULL );
88
89 if( ( f = fopen( path, "rb" ) ) == NULL )
90 return( MBEDTLS_ERR_PK_FILE_IO_ERROR );
91
92 fseek( f, 0, SEEK_END );
93 if( ( size = ftell( f ) ) == -1 )
94 {
95 fclose( f );
96 return( MBEDTLS_ERR_PK_FILE_IO_ERROR );
97 }
98 fseek( f, 0, SEEK_SET );
99
100 *n = (size_t) size;
101
102 if( *n + 1 == 0 ||
103 ( *buf = mbedtls_calloc( 1, *n + 1 ) ) == NULL )
104 {
105 fclose( f );
106 return( MBEDTLS_ERR_PK_ALLOC_FAILED );
107 }
108
109 if( fread( *buf, 1, *n, f ) != *n )
110 {
111 fclose( f );
112
113 mbedtls_platform_zeroize( *buf, *n );
114 mbedtls_free( *buf );
115
116 return( MBEDTLS_ERR_PK_FILE_IO_ERROR );
117 }
118
119 fclose( f );
120
121 (*buf)[*n] = '\0';
122
123 if( strstr( (const char *) *buf, "-----BEGIN " ) != NULL )
124 ++*n;
125
126 return( 0 );
127 }
128
129 /*
130 * Load and parse a private key
131 */
mbedtls_pk_parse_keyfile(mbedtls_pk_context * ctx,const char * path,const char * pwd)132 int mbedtls_pk_parse_keyfile( mbedtls_pk_context *ctx,
133 const char *path, const char *pwd )
134 {
135 int ret;
136 size_t n;
137 unsigned char *buf;
138
139 PK_VALIDATE_RET( ctx != NULL );
140 PK_VALIDATE_RET( path != NULL );
141
142 if( ( ret = mbedtls_pk_load_file( path, &buf, &n ) ) != 0 )
143 return( ret );
144
145 if( pwd == NULL )
146 ret = mbedtls_pk_parse_key( ctx, buf, n, NULL, 0 );
147 else
148 ret = mbedtls_pk_parse_key( ctx, buf, n,
149 (const unsigned char *) pwd, strlen( pwd ) );
150
151 mbedtls_platform_zeroize( buf, n );
152 mbedtls_free( buf );
153
154 return( ret );
155 }
156
157 /*
158 * Load and parse a public key
159 */
mbedtls_pk_parse_public_keyfile(mbedtls_pk_context * ctx,const char * path)160 int mbedtls_pk_parse_public_keyfile( mbedtls_pk_context *ctx, const char *path )
161 {
162 int ret;
163 size_t n;
164 unsigned char *buf;
165
166 PK_VALIDATE_RET( ctx != NULL );
167 PK_VALIDATE_RET( path != NULL );
168
169 if( ( ret = mbedtls_pk_load_file( path, &buf, &n ) ) != 0 )
170 return( ret );
171
172 ret = mbedtls_pk_parse_public_key( ctx, buf, n );
173
174 mbedtls_platform_zeroize( buf, n );
175 mbedtls_free( buf );
176
177 return( ret );
178 }
179 #endif /* MBEDTLS_FS_IO */
180
181 #if defined(MBEDTLS_ECP_C)
182 /* Minimally parse an ECParameters buffer to and mbedtls_asn1_buf
183 *
184 * ECParameters ::= CHOICE {
185 * namedCurve OBJECT IDENTIFIER
186 * specifiedCurve SpecifiedECDomain -- = SEQUENCE { ... }
187 * -- implicitCurve NULL
188 * }
189 */
pk_get_ecparams(unsigned char ** p,const unsigned char * end,mbedtls_asn1_buf * params)190 static int pk_get_ecparams( unsigned char **p, const unsigned char *end,
191 mbedtls_asn1_buf *params )
192 {
193 int ret;
194
195 if ( end - *p < 1 )
196 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT +
197 MBEDTLS_ERR_ASN1_OUT_OF_DATA );
198
199 /* Tag may be either OID or SEQUENCE */
200 params->tag = **p;
201 if( params->tag != MBEDTLS_ASN1_OID
202 #if defined(MBEDTLS_PK_PARSE_EC_EXTENDED)
203 && params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE )
204 #endif
205 )
206 {
207 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT +
208 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
209 }
210
211 if( ( ret = mbedtls_asn1_get_tag( p, end, ¶ms->len, params->tag ) ) != 0 )
212 {
213 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
214 }
215
216 params->p = *p;
217 *p += params->len;
218
219 if( *p != end )
220 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT +
221 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
222
223 return( 0 );
224 }
225
226 #if defined(MBEDTLS_PK_PARSE_EC_EXTENDED)
227 /*
228 * Parse a SpecifiedECDomain (SEC 1 C.2) and (mostly) fill the group with it.
229 * WARNING: the resulting group should only be used with
230 * pk_group_id_from_specified(), since its base point may not be set correctly
231 * if it was encoded compressed.
232 *
233 * SpecifiedECDomain ::= SEQUENCE {
234 * version SpecifiedECDomainVersion(ecdpVer1 | ecdpVer2 | ecdpVer3, ...),
235 * fieldID FieldID {{FieldTypes}},
236 * curve Curve,
237 * base ECPoint,
238 * order INTEGER,
239 * cofactor INTEGER OPTIONAL,
240 * hash HashAlgorithm OPTIONAL,
241 * ...
242 * }
243 *
244 * We only support prime-field as field type, and ignore hash and cofactor.
245 */
pk_group_from_specified(const mbedtls_asn1_buf * params,mbedtls_ecp_group * grp)246 static int pk_group_from_specified( const mbedtls_asn1_buf *params, mbedtls_ecp_group *grp )
247 {
248 int ret;
249 unsigned char *p = params->p;
250 const unsigned char * const end = params->p + params->len;
251 const unsigned char *end_field, *end_curve;
252 size_t len;
253 int ver;
254
255 /* SpecifiedECDomainVersion ::= INTEGER { 1, 2, 3 } */
256 if( ( ret = mbedtls_asn1_get_int( &p, end, &ver ) ) != 0 )
257 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
258
259 if( ver < 1 || ver > 3 )
260 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT );
261
262 /*
263 * FieldID { FIELD-ID:IOSet } ::= SEQUENCE { -- Finite field
264 * fieldType FIELD-ID.&id({IOSet}),
265 * parameters FIELD-ID.&Type({IOSet}{@fieldType})
266 * }
267 */
268 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
269 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
270 return( ret );
271
272 end_field = p + len;
273
274 /*
275 * FIELD-ID ::= TYPE-IDENTIFIER
276 * FieldTypes FIELD-ID ::= {
277 * { Prime-p IDENTIFIED BY prime-field } |
278 * { Characteristic-two IDENTIFIED BY characteristic-two-field }
279 * }
280 * prime-field OBJECT IDENTIFIER ::= { id-fieldType 1 }
281 */
282 if( ( ret = mbedtls_asn1_get_tag( &p, end_field, &len, MBEDTLS_ASN1_OID ) ) != 0 )
283 return( ret );
284
285 if( len != MBEDTLS_OID_SIZE( MBEDTLS_OID_ANSI_X9_62_PRIME_FIELD ) ||
286 memcmp( p, MBEDTLS_OID_ANSI_X9_62_PRIME_FIELD, len ) != 0 )
287 {
288 return( MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE );
289 }
290
291 p += len;
292
293 /* Prime-p ::= INTEGER -- Field of size p. */
294 if( ( ret = mbedtls_asn1_get_mpi( &p, end_field, &grp->P ) ) != 0 )
295 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
296
297 grp->pbits = mbedtls_mpi_bitlen( &grp->P );
298
299 if( p != end_field )
300 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT +
301 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
302
303 /*
304 * Curve ::= SEQUENCE {
305 * a FieldElement,
306 * b FieldElement,
307 * seed BIT STRING OPTIONAL
308 * -- Shall be present if used in SpecifiedECDomain
309 * -- with version equal to ecdpVer2 or ecdpVer3
310 * }
311 */
312 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
313 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
314 return( ret );
315
316 end_curve = p + len;
317
318 /*
319 * FieldElement ::= OCTET STRING
320 * containing an integer in the case of a prime field
321 */
322 if( ( ret = mbedtls_asn1_get_tag( &p, end_curve, &len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 ||
323 ( ret = mbedtls_mpi_read_binary( &grp->A, p, len ) ) != 0 )
324 {
325 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
326 }
327
328 p += len;
329
330 if( ( ret = mbedtls_asn1_get_tag( &p, end_curve, &len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 ||
331 ( ret = mbedtls_mpi_read_binary( &grp->B, p, len ) ) != 0 )
332 {
333 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
334 }
335
336 p += len;
337
338 /* Ignore seed BIT STRING OPTIONAL */
339 if( ( ret = mbedtls_asn1_get_tag( &p, end_curve, &len, MBEDTLS_ASN1_BIT_STRING ) ) == 0 )
340 p += len;
341
342 if( p != end_curve )
343 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT +
344 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
345
346 /*
347 * ECPoint ::= OCTET STRING
348 */
349 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
350 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
351
352 if( ( ret = mbedtls_ecp_point_read_binary( grp, &grp->G,
353 ( const unsigned char *) p, len ) ) != 0 )
354 {
355 /*
356 * If we can't read the point because it's compressed, cheat by
357 * reading only the X coordinate and the parity bit of Y.
358 */
359 if( ret != MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE ||
360 ( p[0] != 0x02 && p[0] != 0x03 ) ||
361 len != mbedtls_mpi_size( &grp->P ) + 1 ||
362 mbedtls_mpi_read_binary( &grp->G.X, p + 1, len - 1 ) != 0 ||
363 mbedtls_mpi_lset( &grp->G.Y, p[0] - 2 ) != 0 ||
364 mbedtls_mpi_lset( &grp->G.Z, 1 ) != 0 )
365 {
366 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT );
367 }
368 }
369
370 p += len;
371
372 /*
373 * order INTEGER
374 */
375 if( ( ret = mbedtls_asn1_get_mpi( &p, end, &grp->N ) ) != 0 )
376 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
377
378 grp->nbits = mbedtls_mpi_bitlen( &grp->N );
379
380 /*
381 * Allow optional elements by purposefully not enforcing p == end here.
382 */
383
384 return( 0 );
385 }
386
387 /*
388 * Find the group id associated with an (almost filled) group as generated by
389 * pk_group_from_specified(), or return an error if unknown.
390 */
pk_group_id_from_group(const mbedtls_ecp_group * grp,mbedtls_ecp_group_id * grp_id)391 static int pk_group_id_from_group( const mbedtls_ecp_group *grp, mbedtls_ecp_group_id *grp_id )
392 {
393 int ret = 0;
394 mbedtls_ecp_group ref;
395 const mbedtls_ecp_group_id *id;
396
397 mbedtls_ecp_group_init( &ref );
398
399 for( id = mbedtls_ecp_grp_id_list(); *id != MBEDTLS_ECP_DP_NONE; id++ )
400 {
401 /* Load the group associated to that id */
402 mbedtls_ecp_group_free( &ref );
403 MBEDTLS_MPI_CHK( mbedtls_ecp_group_load( &ref, *id ) );
404
405 /* Compare to the group we were given, starting with easy tests */
406 if( grp->pbits == ref.pbits && grp->nbits == ref.nbits &&
407 mbedtls_mpi_cmp_mpi( &grp->P, &ref.P ) == 0 &&
408 mbedtls_mpi_cmp_mpi( &grp->A, &ref.A ) == 0 &&
409 mbedtls_mpi_cmp_mpi( &grp->B, &ref.B ) == 0 &&
410 mbedtls_mpi_cmp_mpi( &grp->N, &ref.N ) == 0 &&
411 mbedtls_mpi_cmp_mpi( &grp->G.X, &ref.G.X ) == 0 &&
412 mbedtls_mpi_cmp_mpi( &grp->G.Z, &ref.G.Z ) == 0 &&
413 /* For Y we may only know the parity bit, so compare only that */
414 mbedtls_mpi_get_bit( &grp->G.Y, 0 ) == mbedtls_mpi_get_bit( &ref.G.Y, 0 ) )
415 {
416 break;
417 }
418
419 }
420
421 cleanup:
422 mbedtls_ecp_group_free( &ref );
423
424 *grp_id = *id;
425
426 if( ret == 0 && *id == MBEDTLS_ECP_DP_NONE )
427 ret = MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE;
428
429 return( ret );
430 }
431
432 /*
433 * Parse a SpecifiedECDomain (SEC 1 C.2) and find the associated group ID
434 */
pk_group_id_from_specified(const mbedtls_asn1_buf * params,mbedtls_ecp_group_id * grp_id)435 static int pk_group_id_from_specified( const mbedtls_asn1_buf *params,
436 mbedtls_ecp_group_id *grp_id )
437 {
438 int ret;
439 mbedtls_ecp_group grp;
440
441 mbedtls_ecp_group_init( &grp );
442
443 if( ( ret = pk_group_from_specified( params, &grp ) ) != 0 )
444 goto cleanup;
445
446 ret = pk_group_id_from_group( &grp, grp_id );
447
448 cleanup:
449 mbedtls_ecp_group_free( &grp );
450
451 return( ret );
452 }
453 #endif /* MBEDTLS_PK_PARSE_EC_EXTENDED */
454
455 /*
456 * Use EC parameters to initialise an EC group
457 *
458 * ECParameters ::= CHOICE {
459 * namedCurve OBJECT IDENTIFIER
460 * specifiedCurve SpecifiedECDomain -- = SEQUENCE { ... }
461 * -- implicitCurve NULL
462 */
pk_use_ecparams(const mbedtls_asn1_buf * params,mbedtls_ecp_group * grp)463 static int pk_use_ecparams( const mbedtls_asn1_buf *params, mbedtls_ecp_group *grp )
464 {
465 int ret;
466 mbedtls_ecp_group_id grp_id;
467
468 if( params->tag == MBEDTLS_ASN1_OID )
469 {
470 if( mbedtls_oid_get_ec_grp( params, &grp_id ) != 0 )
471 return( MBEDTLS_ERR_PK_UNKNOWN_NAMED_CURVE );
472 }
473 else
474 {
475 #if defined(MBEDTLS_PK_PARSE_EC_EXTENDED)
476 if( ( ret = pk_group_id_from_specified( params, &grp_id ) ) != 0 )
477 return( ret );
478 #else
479 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT );
480 #endif
481 }
482
483 /*
484 * grp may already be initilialized; if so, make sure IDs match
485 */
486 if( grp->id != MBEDTLS_ECP_DP_NONE && grp->id != grp_id )
487 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT );
488
489 if( ( ret = mbedtls_ecp_group_load( grp, grp_id ) ) != 0 )
490 return( ret );
491
492 return( 0 );
493 }
494
495 /*
496 * EC public key is an EC point
497 *
498 * The caller is responsible for clearing the structure upon failure if
499 * desired. Take care to pass along the possible ECP_FEATURE_UNAVAILABLE
500 * return code of mbedtls_ecp_point_read_binary() and leave p in a usable state.
501 */
pk_get_ecpubkey(unsigned char ** p,const unsigned char * end,mbedtls_ecp_keypair * key)502 static int pk_get_ecpubkey( unsigned char **p, const unsigned char *end,
503 mbedtls_ecp_keypair *key )
504 {
505 int ret;
506
507 if( ( ret = mbedtls_ecp_point_read_binary( &key->grp, &key->Q,
508 (const unsigned char *) *p, end - *p ) ) == 0 )
509 {
510 ret = mbedtls_ecp_check_pubkey( &key->grp, &key->Q );
511 }
512
513 /*
514 * We know mbedtls_ecp_point_read_binary consumed all bytes or failed
515 */
516 *p = (unsigned char *) end;
517
518 return( ret );
519 }
520 #endif /* MBEDTLS_ECP_C */
521
522 #if defined(MBEDTLS_RSA_C)
523 /*
524 * RSAPublicKey ::= SEQUENCE {
525 * modulus INTEGER, -- n
526 * publicExponent INTEGER -- e
527 * }
528 */
pk_get_rsapubkey(unsigned char ** p,const unsigned char * end,mbedtls_rsa_context * rsa)529 static int pk_get_rsapubkey( unsigned char **p,
530 const unsigned char *end,
531 mbedtls_rsa_context *rsa )
532 {
533 int ret;
534 size_t len;
535
536 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
537 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
538 return( MBEDTLS_ERR_PK_INVALID_PUBKEY + ret );
539
540 if( *p + len != end )
541 return( MBEDTLS_ERR_PK_INVALID_PUBKEY +
542 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
543
544 /* Import N */
545 if( ( ret = mbedtls_asn1_get_tag( p, end, &len, MBEDTLS_ASN1_INTEGER ) ) != 0 )
546 return( MBEDTLS_ERR_PK_INVALID_PUBKEY + ret );
547
548 if( ( ret = mbedtls_rsa_import_raw( rsa, *p, len, NULL, 0, NULL, 0,
549 NULL, 0, NULL, 0 ) ) != 0 )
550 return( MBEDTLS_ERR_PK_INVALID_PUBKEY );
551
552 *p += len;
553
554 /* Import E */
555 if( ( ret = mbedtls_asn1_get_tag( p, end, &len, MBEDTLS_ASN1_INTEGER ) ) != 0 )
556 return( MBEDTLS_ERR_PK_INVALID_PUBKEY + ret );
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 *p += len;
563
564 if( mbedtls_rsa_complete( rsa ) != 0 ||
565 mbedtls_rsa_check_pubkey( rsa ) != 0 )
566 {
567 return( MBEDTLS_ERR_PK_INVALID_PUBKEY );
568 }
569
570 if( *p != end )
571 return( MBEDTLS_ERR_PK_INVALID_PUBKEY +
572 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
573
574 return( 0 );
575 }
576 #endif /* MBEDTLS_RSA_C */
577
578 /* Get a PK algorithm identifier
579 *
580 * AlgorithmIdentifier ::= SEQUENCE {
581 * algorithm OBJECT IDENTIFIER,
582 * parameters ANY DEFINED BY algorithm OPTIONAL }
583 */
pk_get_pk_alg(unsigned char ** p,const unsigned char * end,mbedtls_pk_type_t * pk_alg,mbedtls_asn1_buf * params)584 static int pk_get_pk_alg( unsigned char **p,
585 const unsigned char *end,
586 mbedtls_pk_type_t *pk_alg, mbedtls_asn1_buf *params )
587 {
588 int ret;
589 mbedtls_asn1_buf alg_oid;
590
591 memset( params, 0, sizeof(mbedtls_asn1_buf) );
592
593 if( ( ret = mbedtls_asn1_get_alg( p, end, &alg_oid, params ) ) != 0 )
594 return( MBEDTLS_ERR_PK_INVALID_ALG + ret );
595
596 if( mbedtls_oid_get_pk_alg( &alg_oid, pk_alg ) != 0 )
597 return( MBEDTLS_ERR_PK_UNKNOWN_PK_ALG );
598
599 /*
600 * No parameters with RSA (only for EC)
601 */
602 if( *pk_alg == MBEDTLS_PK_RSA &&
603 ( ( params->tag != MBEDTLS_ASN1_NULL && params->tag != 0 ) ||
604 params->len != 0 ) )
605 {
606 return( MBEDTLS_ERR_PK_INVALID_ALG );
607 }
608
609 return( 0 );
610 }
611
612 /*
613 * SubjectPublicKeyInfo ::= SEQUENCE {
614 * algorithm AlgorithmIdentifier,
615 * subjectPublicKey BIT STRING }
616 */
mbedtls_pk_parse_subpubkey(unsigned char ** p,const unsigned char * end,mbedtls_pk_context * pk)617 int mbedtls_pk_parse_subpubkey( unsigned char **p, const unsigned char *end,
618 mbedtls_pk_context *pk )
619 {
620 int ret;
621 size_t len;
622 mbedtls_asn1_buf alg_params;
623 mbedtls_pk_type_t pk_alg = MBEDTLS_PK_NONE;
624 const mbedtls_pk_info_t *pk_info;
625
626 PK_VALIDATE_RET( p != NULL );
627 PK_VALIDATE_RET( *p != NULL );
628 PK_VALIDATE_RET( end != NULL );
629 PK_VALIDATE_RET( pk != NULL );
630
631 if( ( ret = mbedtls_asn1_get_tag( p, end, &len,
632 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
633 {
634 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
635 }
636
637 end = *p + len;
638
639 if( ( ret = pk_get_pk_alg( p, end, &pk_alg, &alg_params ) ) != 0 )
640 return( ret );
641
642 if( ( ret = mbedtls_asn1_get_bitstring_null( p, end, &len ) ) != 0 )
643 return( MBEDTLS_ERR_PK_INVALID_PUBKEY + ret );
644
645 if( *p + len != end )
646 return( MBEDTLS_ERR_PK_INVALID_PUBKEY +
647 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
648
649 if( ( pk_info = mbedtls_pk_info_from_type( pk_alg ) ) == NULL )
650 return( MBEDTLS_ERR_PK_UNKNOWN_PK_ALG );
651
652 if( ( ret = mbedtls_pk_setup( pk, pk_info ) ) != 0 )
653 return( ret );
654
655 #if defined(MBEDTLS_RSA_C)
656 if( pk_alg == MBEDTLS_PK_RSA )
657 {
658 ret = pk_get_rsapubkey( p, end, mbedtls_pk_rsa( *pk ) );
659 } else
660 #endif /* MBEDTLS_RSA_C */
661 #if defined(MBEDTLS_ECP_C)
662 if( pk_alg == MBEDTLS_PK_ECKEY_DH || pk_alg == MBEDTLS_PK_ECKEY )
663 {
664 ret = pk_use_ecparams( &alg_params, &mbedtls_pk_ec( *pk )->grp );
665 if( ret == 0 )
666 ret = pk_get_ecpubkey( p, end, mbedtls_pk_ec( *pk ) );
667 } else
668 #endif /* MBEDTLS_ECP_C */
669 ret = MBEDTLS_ERR_PK_UNKNOWN_PK_ALG;
670
671 if( ret == 0 && *p != end )
672 ret = MBEDTLS_ERR_PK_INVALID_PUBKEY
673 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH;
674
675 if( ret != 0 )
676 mbedtls_pk_free( pk );
677
678 return( ret );
679 }
680
681 #if defined(MBEDTLS_RSA_C)
682 /*
683 * Parse a PKCS#1 encoded private RSA key
684 */
pk_parse_key_pkcs1_der(mbedtls_rsa_context * rsa,const unsigned char * key,size_t keylen)685 static int pk_parse_key_pkcs1_der( mbedtls_rsa_context *rsa,
686 const unsigned char *key,
687 size_t keylen )
688 {
689 int ret, version;
690 size_t len;
691 unsigned char *p, *end;
692
693 mbedtls_mpi T;
694 mbedtls_mpi_init( &T );
695
696 p = (unsigned char *) key;
697 end = p + keylen;
698
699 /*
700 * This function parses the RSAPrivateKey (PKCS#1)
701 *
702 * RSAPrivateKey ::= SEQUENCE {
703 * version Version,
704 * modulus INTEGER, -- n
705 * publicExponent INTEGER, -- e
706 * privateExponent INTEGER, -- d
707 * prime1 INTEGER, -- p
708 * prime2 INTEGER, -- q
709 * exponent1 INTEGER, -- d mod (p-1)
710 * exponent2 INTEGER, -- d mod (q-1)
711 * coefficient INTEGER, -- (inverse of q) mod p
712 * otherPrimeInfos OtherPrimeInfos OPTIONAL
713 * }
714 */
715 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
716 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
717 {
718 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
719 }
720
721 end = p + len;
722
723 if( ( ret = mbedtls_asn1_get_int( &p, end, &version ) ) != 0 )
724 {
725 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
726 }
727
728 if( version != 0 )
729 {
730 return( MBEDTLS_ERR_PK_KEY_INVALID_VERSION );
731 }
732
733 /* Import N */
734 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
735 MBEDTLS_ASN1_INTEGER ) ) != 0 ||
736 ( ret = mbedtls_rsa_import_raw( rsa, p, len, NULL, 0, NULL, 0,
737 NULL, 0, NULL, 0 ) ) != 0 )
738 goto cleanup;
739 p += len;
740
741 /* Import E */
742 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
743 MBEDTLS_ASN1_INTEGER ) ) != 0 ||
744 ( ret = mbedtls_rsa_import_raw( rsa, NULL, 0, NULL, 0, NULL, 0,
745 NULL, 0, p, len ) ) != 0 )
746 goto cleanup;
747 p += len;
748
749 /* Import D */
750 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
751 MBEDTLS_ASN1_INTEGER ) ) != 0 ||
752 ( ret = mbedtls_rsa_import_raw( rsa, NULL, 0, NULL, 0, NULL, 0,
753 p, len, NULL, 0 ) ) != 0 )
754 goto cleanup;
755 p += len;
756
757 /* Import P */
758 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
759 MBEDTLS_ASN1_INTEGER ) ) != 0 ||
760 ( ret = mbedtls_rsa_import_raw( rsa, NULL, 0, p, len, NULL, 0,
761 NULL, 0, NULL, 0 ) ) != 0 )
762 goto cleanup;
763 p += len;
764
765 /* Import Q */
766 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
767 MBEDTLS_ASN1_INTEGER ) ) != 0 ||
768 ( ret = mbedtls_rsa_import_raw( rsa, NULL, 0, NULL, 0, p, len,
769 NULL, 0, NULL, 0 ) ) != 0 )
770 goto cleanup;
771 p += len;
772
773 /* Complete the RSA private key */
774 if( ( ret = mbedtls_rsa_complete( rsa ) ) != 0 )
775 goto cleanup;
776
777 /* Check optional parameters */
778 if( ( ret = mbedtls_asn1_get_mpi( &p, end, &T ) ) != 0 ||
779 ( ret = mbedtls_asn1_get_mpi( &p, end, &T ) ) != 0 ||
780 ( ret = mbedtls_asn1_get_mpi( &p, end, &T ) ) != 0 )
781 goto cleanup;
782
783 if( p != end )
784 {
785 ret = MBEDTLS_ERR_PK_KEY_INVALID_FORMAT +
786 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ;
787 }
788
789 cleanup:
790
791 mbedtls_mpi_free( &T );
792
793 if( ret != 0 )
794 {
795 /* Wrap error code if it's coming from a lower level */
796 if( ( ret & 0xff80 ) == 0 )
797 ret = MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret;
798 else
799 ret = MBEDTLS_ERR_PK_KEY_INVALID_FORMAT;
800
801 mbedtls_rsa_free( rsa );
802 }
803
804 return( ret );
805 }
806 #endif /* MBEDTLS_RSA_C */
807
808 #if defined(MBEDTLS_ECP_C)
809 /*
810 * Parse a SEC1 encoded private EC key
811 */
pk_parse_key_sec1_der(mbedtls_ecp_keypair * eck,const unsigned char * key,size_t keylen)812 static int pk_parse_key_sec1_der( mbedtls_ecp_keypair *eck,
813 const unsigned char *key,
814 size_t keylen )
815 {
816 int ret;
817 int version, pubkey_done;
818 size_t len;
819 mbedtls_asn1_buf params;
820 unsigned char *p = (unsigned char *) key;
821 unsigned char *end = p + keylen;
822 unsigned char *end2;
823
824 /*
825 * RFC 5915, or SEC1 Appendix C.4
826 *
827 * ECPrivateKey ::= SEQUENCE {
828 * version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
829 * privateKey OCTET STRING,
830 * parameters [0] ECParameters {{ NamedCurve }} OPTIONAL,
831 * publicKey [1] BIT STRING OPTIONAL
832 * }
833 */
834 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
835 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
836 {
837 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
838 }
839
840 end = p + len;
841
842 if( ( ret = mbedtls_asn1_get_int( &p, end, &version ) ) != 0 )
843 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
844
845 if( version != 1 )
846 return( MBEDTLS_ERR_PK_KEY_INVALID_VERSION );
847
848 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
849 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
850
851 if( ( ret = mbedtls_mpi_read_binary( &eck->d, p, len ) ) != 0 )
852 {
853 mbedtls_ecp_keypair_free( eck );
854 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
855 }
856
857 p += len;
858
859 pubkey_done = 0;
860 if( p != end )
861 {
862 /*
863 * Is 'parameters' present?
864 */
865 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
866 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 0 ) ) == 0 )
867 {
868 if( ( ret = pk_get_ecparams( &p, p + len, ¶ms) ) != 0 ||
869 ( ret = pk_use_ecparams( ¶ms, &eck->grp ) ) != 0 )
870 {
871 mbedtls_ecp_keypair_free( eck );
872 return( ret );
873 }
874 }
875 else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
876 {
877 mbedtls_ecp_keypair_free( eck );
878 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
879 }
880 }
881
882 if( p != end )
883 {
884 /*
885 * Is 'publickey' present? If not, or if we can't read it (eg because it
886 * is compressed), create it from the private key.
887 */
888 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
889 MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 1 ) ) == 0 )
890 {
891 end2 = p + len;
892
893 if( ( ret = mbedtls_asn1_get_bitstring_null( &p, end2, &len ) ) != 0 )
894 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
895
896 if( p + len != end2 )
897 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT +
898 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
899
900 if( ( ret = pk_get_ecpubkey( &p, end2, eck ) ) == 0 )
901 pubkey_done = 1;
902 else
903 {
904 /*
905 * The only acceptable failure mode of pk_get_ecpubkey() above
906 * is if the point format is not recognized.
907 */
908 if( ret != MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE )
909 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT );
910 }
911 }
912 else if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
913 {
914 mbedtls_ecp_keypair_free( eck );
915 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
916 }
917 }
918
919 if( ! pubkey_done &&
920 ( ret = mbedtls_ecp_mul( &eck->grp, &eck->Q, &eck->d, &eck->grp.G,
921 NULL, NULL ) ) != 0 )
922 {
923 mbedtls_ecp_keypair_free( eck );
924 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
925 }
926
927 if( ( ret = mbedtls_ecp_check_privkey( &eck->grp, &eck->d ) ) != 0 )
928 {
929 mbedtls_ecp_keypair_free( eck );
930 return( ret );
931 }
932
933 return( 0 );
934 }
935 #endif /* MBEDTLS_ECP_C */
936
937 /*
938 * Parse an unencrypted PKCS#8 encoded private key
939 *
940 * Notes:
941 *
942 * - This function does not own the key buffer. It is the
943 * responsibility of the caller to take care of zeroizing
944 * and freeing it after use.
945 *
946 * - The function is responsible for freeing the provided
947 * PK context on failure.
948 *
949 */
pk_parse_key_pkcs8_unencrypted_der(mbedtls_pk_context * pk,const unsigned char * key,size_t keylen)950 static int pk_parse_key_pkcs8_unencrypted_der(
951 mbedtls_pk_context *pk,
952 const unsigned char* key,
953 size_t keylen )
954 {
955 int ret, version;
956 size_t len;
957 mbedtls_asn1_buf params;
958 unsigned char *p = (unsigned char *) key;
959 unsigned char *end = p + keylen;
960 mbedtls_pk_type_t pk_alg = MBEDTLS_PK_NONE;
961 const mbedtls_pk_info_t *pk_info;
962
963 /*
964 * This function parses the PrivateKeyInfo object (PKCS#8 v1.2 = RFC 5208)
965 *
966 * PrivateKeyInfo ::= SEQUENCE {
967 * version Version,
968 * privateKeyAlgorithm PrivateKeyAlgorithmIdentifier,
969 * privateKey PrivateKey,
970 * attributes [0] IMPLICIT Attributes OPTIONAL }
971 *
972 * Version ::= INTEGER
973 * PrivateKeyAlgorithmIdentifier ::= AlgorithmIdentifier
974 * PrivateKey ::= OCTET STRING
975 *
976 * The PrivateKey OCTET STRING is a SEC1 ECPrivateKey
977 */
978
979 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
980 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
981 {
982 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
983 }
984
985 end = p + len;
986
987 if( ( ret = mbedtls_asn1_get_int( &p, end, &version ) ) != 0 )
988 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
989
990 if( version != 0 )
991 return( MBEDTLS_ERR_PK_KEY_INVALID_VERSION + ret );
992
993 if( ( ret = pk_get_pk_alg( &p, end, &pk_alg, ¶ms ) ) != 0 )
994 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
995
996 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
997 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
998
999 if( len < 1 )
1000 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT +
1001 MBEDTLS_ERR_ASN1_OUT_OF_DATA );
1002
1003 if( ( pk_info = mbedtls_pk_info_from_type( pk_alg ) ) == NULL )
1004 return( MBEDTLS_ERR_PK_UNKNOWN_PK_ALG );
1005
1006 if( ( ret = mbedtls_pk_setup( pk, pk_info ) ) != 0 )
1007 return( ret );
1008
1009 #if defined(MBEDTLS_RSA_C)
1010 if( pk_alg == MBEDTLS_PK_RSA )
1011 {
1012 if( ( ret = pk_parse_key_pkcs1_der( mbedtls_pk_rsa( *pk ), p, len ) ) != 0 )
1013 {
1014 mbedtls_pk_free( pk );
1015 return( ret );
1016 }
1017 } else
1018 #endif /* MBEDTLS_RSA_C */
1019 #if defined(MBEDTLS_ECP_C)
1020 if( pk_alg == MBEDTLS_PK_ECKEY || pk_alg == MBEDTLS_PK_ECKEY_DH )
1021 {
1022 if( ( ret = pk_use_ecparams( ¶ms, &mbedtls_pk_ec( *pk )->grp ) ) != 0 ||
1023 ( ret = pk_parse_key_sec1_der( mbedtls_pk_ec( *pk ), p, len ) ) != 0 )
1024 {
1025 mbedtls_pk_free( pk );
1026 return( ret );
1027 }
1028 } else
1029 #endif /* MBEDTLS_ECP_C */
1030 return( MBEDTLS_ERR_PK_UNKNOWN_PK_ALG );
1031
1032 return( 0 );
1033 }
1034
1035 /*
1036 * Parse an encrypted PKCS#8 encoded private key
1037 *
1038 * To save space, the decryption happens in-place on the given key buffer.
1039 * Also, while this function may modify the keybuffer, it doesn't own it,
1040 * and instead it is the responsibility of the caller to zeroize and properly
1041 * free it after use.
1042 *
1043 */
1044 #if defined(MBEDTLS_PKCS12_C) || defined(MBEDTLS_PKCS5_C)
pk_parse_key_pkcs8_encrypted_der(mbedtls_pk_context * pk,unsigned char * key,size_t keylen,const unsigned char * pwd,size_t pwdlen)1045 static int pk_parse_key_pkcs8_encrypted_der(
1046 mbedtls_pk_context *pk,
1047 unsigned char *key, size_t keylen,
1048 const unsigned char *pwd, size_t pwdlen )
1049 {
1050 int ret, decrypted = 0;
1051 size_t len;
1052 unsigned char *buf;
1053 unsigned char *p, *end;
1054 mbedtls_asn1_buf pbe_alg_oid, pbe_params;
1055 #if defined(MBEDTLS_PKCS12_C)
1056 mbedtls_cipher_type_t cipher_alg;
1057 mbedtls_md_type_t md_alg;
1058 #endif
1059
1060 p = key;
1061 end = p + keylen;
1062
1063 if( pwdlen == 0 )
1064 return( MBEDTLS_ERR_PK_PASSWORD_REQUIRED );
1065
1066 /*
1067 * This function parses the EncryptedPrivateKeyInfo object (PKCS#8)
1068 *
1069 * EncryptedPrivateKeyInfo ::= SEQUENCE {
1070 * encryptionAlgorithm EncryptionAlgorithmIdentifier,
1071 * encryptedData EncryptedData
1072 * }
1073 *
1074 * EncryptionAlgorithmIdentifier ::= AlgorithmIdentifier
1075 *
1076 * EncryptedData ::= OCTET STRING
1077 *
1078 * The EncryptedData OCTET STRING is a PKCS#8 PrivateKeyInfo
1079 *
1080 */
1081 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len,
1082 MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 )
1083 {
1084 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
1085 }
1086
1087 end = p + len;
1088
1089 if( ( ret = mbedtls_asn1_get_alg( &p, end, &pbe_alg_oid, &pbe_params ) ) != 0 )
1090 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
1091
1092 if( ( ret = mbedtls_asn1_get_tag( &p, end, &len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
1093 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT + ret );
1094
1095 buf = p;
1096
1097 /*
1098 * Decrypt EncryptedData with appropriate PBE
1099 */
1100 #if defined(MBEDTLS_PKCS12_C)
1101 if( mbedtls_oid_get_pkcs12_pbe_alg( &pbe_alg_oid, &md_alg, &cipher_alg ) == 0 )
1102 {
1103 if( ( ret = mbedtls_pkcs12_pbe( &pbe_params, MBEDTLS_PKCS12_PBE_DECRYPT,
1104 cipher_alg, md_alg,
1105 pwd, pwdlen, p, len, buf ) ) != 0 )
1106 {
1107 if( ret == MBEDTLS_ERR_PKCS12_PASSWORD_MISMATCH )
1108 return( MBEDTLS_ERR_PK_PASSWORD_MISMATCH );
1109
1110 return( ret );
1111 }
1112
1113 decrypted = 1;
1114 }
1115 else if( MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS12_PBE_SHA1_RC4_128, &pbe_alg_oid ) == 0 )
1116 {
1117 if( ( ret = mbedtls_pkcs12_pbe_sha1_rc4_128( &pbe_params,
1118 MBEDTLS_PKCS12_PBE_DECRYPT,
1119 pwd, pwdlen,
1120 p, len, buf ) ) != 0 )
1121 {
1122 return( ret );
1123 }
1124
1125 // Best guess for password mismatch when using RC4. If first tag is
1126 // not MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE
1127 //
1128 if( *buf != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
1129 return( MBEDTLS_ERR_PK_PASSWORD_MISMATCH );
1130
1131 decrypted = 1;
1132 }
1133 else
1134 #endif /* MBEDTLS_PKCS12_C */
1135 #if defined(MBEDTLS_PKCS5_C)
1136 if( MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS5_PBES2, &pbe_alg_oid ) == 0 )
1137 {
1138 if( ( ret = mbedtls_pkcs5_pbes2( &pbe_params, MBEDTLS_PKCS5_DECRYPT, pwd, pwdlen,
1139 p, len, buf ) ) != 0 )
1140 {
1141 if( ret == MBEDTLS_ERR_PKCS5_PASSWORD_MISMATCH )
1142 return( MBEDTLS_ERR_PK_PASSWORD_MISMATCH );
1143
1144 return( ret );
1145 }
1146
1147 decrypted = 1;
1148 }
1149 else
1150 #endif /* MBEDTLS_PKCS5_C */
1151 {
1152 ((void) pwd);
1153 }
1154
1155 if( decrypted == 0 )
1156 return( MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE );
1157
1158 return( pk_parse_key_pkcs8_unencrypted_der( pk, buf, len ) );
1159 }
1160 #endif /* MBEDTLS_PKCS12_C || MBEDTLS_PKCS5_C */
1161
1162 /*
1163 * Parse a private key
1164 */
mbedtls_pk_parse_key(mbedtls_pk_context * pk,const unsigned char * key,size_t keylen,const unsigned char * pwd,size_t pwdlen)1165 int mbedtls_pk_parse_key( mbedtls_pk_context *pk,
1166 const unsigned char *key, size_t keylen,
1167 const unsigned char *pwd, size_t pwdlen )
1168 {
1169 int ret;
1170 const mbedtls_pk_info_t *pk_info;
1171 #if defined(MBEDTLS_PEM_PARSE_C)
1172 size_t len;
1173 mbedtls_pem_context pem;
1174 #endif
1175
1176 PK_VALIDATE_RET( pk != NULL );
1177 if( keylen == 0 )
1178 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT );
1179 PK_VALIDATE_RET( key != NULL );
1180
1181 #if defined(MBEDTLS_PEM_PARSE_C)
1182 mbedtls_pem_init( &pem );
1183
1184 #if defined(MBEDTLS_RSA_C)
1185 /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
1186 if( key[keylen - 1] != '\0' )
1187 ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
1188 else
1189 ret = mbedtls_pem_read_buffer( &pem,
1190 "-----BEGIN RSA PRIVATE KEY-----",
1191 "-----END RSA PRIVATE KEY-----",
1192 key, pwd, pwdlen, &len );
1193
1194 if( ret == 0 )
1195 {
1196 pk_info = mbedtls_pk_info_from_type( MBEDTLS_PK_RSA );
1197 if( ( ret = mbedtls_pk_setup( pk, pk_info ) ) != 0 ||
1198 ( ret = pk_parse_key_pkcs1_der( mbedtls_pk_rsa( *pk ),
1199 pem.buf, pem.buflen ) ) != 0 )
1200 {
1201 mbedtls_pk_free( pk );
1202 }
1203
1204 mbedtls_pem_free( &pem );
1205 return( ret );
1206 }
1207 else if( ret == MBEDTLS_ERR_PEM_PASSWORD_MISMATCH )
1208 return( MBEDTLS_ERR_PK_PASSWORD_MISMATCH );
1209 else if( ret == MBEDTLS_ERR_PEM_PASSWORD_REQUIRED )
1210 return( MBEDTLS_ERR_PK_PASSWORD_REQUIRED );
1211 else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
1212 return( ret );
1213 #endif /* MBEDTLS_RSA_C */
1214
1215 #if defined(MBEDTLS_ECP_C)
1216 /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
1217 if( key[keylen - 1] != '\0' )
1218 ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
1219 else
1220 ret = mbedtls_pem_read_buffer( &pem,
1221 "-----BEGIN EC PRIVATE KEY-----",
1222 "-----END EC PRIVATE KEY-----",
1223 key, pwd, pwdlen, &len );
1224 if( ret == 0 )
1225 {
1226 pk_info = mbedtls_pk_info_from_type( MBEDTLS_PK_ECKEY );
1227
1228 if( ( ret = mbedtls_pk_setup( pk, pk_info ) ) != 0 ||
1229 ( ret = pk_parse_key_sec1_der( mbedtls_pk_ec( *pk ),
1230 pem.buf, pem.buflen ) ) != 0 )
1231 {
1232 mbedtls_pk_free( pk );
1233 }
1234
1235 mbedtls_pem_free( &pem );
1236 return( ret );
1237 }
1238 else if( ret == MBEDTLS_ERR_PEM_PASSWORD_MISMATCH )
1239 return( MBEDTLS_ERR_PK_PASSWORD_MISMATCH );
1240 else if( ret == MBEDTLS_ERR_PEM_PASSWORD_REQUIRED )
1241 return( MBEDTLS_ERR_PK_PASSWORD_REQUIRED );
1242 else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
1243 return( ret );
1244 #endif /* MBEDTLS_ECP_C */
1245
1246 /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
1247 if( key[keylen - 1] != '\0' )
1248 ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
1249 else
1250 ret = mbedtls_pem_read_buffer( &pem,
1251 "-----BEGIN PRIVATE KEY-----",
1252 "-----END PRIVATE KEY-----",
1253 key, NULL, 0, &len );
1254 if( ret == 0 )
1255 {
1256 if( ( ret = pk_parse_key_pkcs8_unencrypted_der( pk,
1257 pem.buf, pem.buflen ) ) != 0 )
1258 {
1259 mbedtls_pk_free( pk );
1260 }
1261
1262 mbedtls_pem_free( &pem );
1263 return( ret );
1264 }
1265 else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
1266 return( ret );
1267
1268 #if defined(MBEDTLS_PKCS12_C) || defined(MBEDTLS_PKCS5_C)
1269 /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
1270 if( key[keylen - 1] != '\0' )
1271 ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
1272 else
1273 ret = mbedtls_pem_read_buffer( &pem,
1274 "-----BEGIN ENCRYPTED PRIVATE KEY-----",
1275 "-----END ENCRYPTED PRIVATE KEY-----",
1276 key, NULL, 0, &len );
1277 if( ret == 0 )
1278 {
1279 if( ( ret = pk_parse_key_pkcs8_encrypted_der( pk,
1280 pem.buf, pem.buflen,
1281 pwd, pwdlen ) ) != 0 )
1282 {
1283 mbedtls_pk_free( pk );
1284 }
1285
1286 mbedtls_pem_free( &pem );
1287 return( ret );
1288 }
1289 else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
1290 return( ret );
1291 #endif /* MBEDTLS_PKCS12_C || MBEDTLS_PKCS5_C */
1292 #else
1293 ((void) pwd);
1294 ((void) pwdlen);
1295 #endif /* MBEDTLS_PEM_PARSE_C */
1296
1297 /*
1298 * At this point we only know it's not a PEM formatted key. Could be any
1299 * of the known DER encoded private key formats
1300 *
1301 * We try the different DER format parsers to see if one passes without
1302 * error
1303 */
1304 #if defined(MBEDTLS_PKCS12_C) || defined(MBEDTLS_PKCS5_C)
1305 {
1306 unsigned char *key_copy;
1307
1308 if( ( key_copy = mbedtls_calloc( 1, keylen ) ) == NULL )
1309 return( MBEDTLS_ERR_PK_ALLOC_FAILED );
1310
1311 memcpy( key_copy, key, keylen );
1312
1313 ret = pk_parse_key_pkcs8_encrypted_der( pk, key_copy, keylen,
1314 pwd, pwdlen );
1315
1316 mbedtls_platform_zeroize( key_copy, keylen );
1317 mbedtls_free( key_copy );
1318 }
1319
1320 if( ret == 0 )
1321 return( 0 );
1322
1323 mbedtls_pk_free( pk );
1324 mbedtls_pk_init( pk );
1325
1326 if( ret == MBEDTLS_ERR_PK_PASSWORD_MISMATCH )
1327 {
1328 return( ret );
1329 }
1330 #endif /* MBEDTLS_PKCS12_C || MBEDTLS_PKCS5_C */
1331
1332 if( ( ret = pk_parse_key_pkcs8_unencrypted_der( pk, key, keylen ) ) == 0 )
1333 return( 0 );
1334
1335 mbedtls_pk_free( pk );
1336 mbedtls_pk_init( pk );
1337
1338 #if defined(MBEDTLS_RSA_C)
1339
1340 pk_info = mbedtls_pk_info_from_type( MBEDTLS_PK_RSA );
1341 if( mbedtls_pk_setup( pk, pk_info ) == 0 &&
1342 pk_parse_key_pkcs1_der( mbedtls_pk_rsa( *pk ), key, keylen ) == 0 )
1343 {
1344 return( 0 );
1345 }
1346
1347 mbedtls_pk_free( pk );
1348 mbedtls_pk_init( pk );
1349 #endif /* MBEDTLS_RSA_C */
1350
1351 #if defined(MBEDTLS_ECP_C)
1352 pk_info = mbedtls_pk_info_from_type( MBEDTLS_PK_ECKEY );
1353 if( mbedtls_pk_setup( pk, pk_info ) == 0 &&
1354 pk_parse_key_sec1_der( mbedtls_pk_ec( *pk ),
1355 key, keylen ) == 0 )
1356 {
1357 return( 0 );
1358 }
1359 mbedtls_pk_free( pk );
1360 #endif /* MBEDTLS_ECP_C */
1361
1362 /* If MBEDTLS_RSA_C is defined but MBEDTLS_ECP_C isn't,
1363 * it is ok to leave the PK context initialized but not
1364 * freed: It is the caller's responsibility to call pk_init()
1365 * before calling this function, and to call pk_free()
1366 * when it fails. If MBEDTLS_ECP_C is defined but MBEDTLS_RSA_C
1367 * isn't, this leads to mbedtls_pk_free() being called
1368 * twice, once here and once by the caller, but this is
1369 * also ok and in line with the mbedtls_pk_free() calls
1370 * on failed PEM parsing attempts. */
1371
1372 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT );
1373 }
1374
1375 /*
1376 * Parse a public key
1377 */
mbedtls_pk_parse_public_key(mbedtls_pk_context * ctx,const unsigned char * key,size_t keylen)1378 int mbedtls_pk_parse_public_key( mbedtls_pk_context *ctx,
1379 const unsigned char *key, size_t keylen )
1380 {
1381 int ret;
1382 unsigned char *p;
1383 #if defined(MBEDTLS_RSA_C)
1384 const mbedtls_pk_info_t *pk_info;
1385 #endif
1386 #if defined(MBEDTLS_PEM_PARSE_C)
1387 size_t len;
1388 mbedtls_pem_context pem;
1389 #endif
1390
1391 PK_VALIDATE_RET( ctx != NULL );
1392 if( keylen == 0 )
1393 return( MBEDTLS_ERR_PK_KEY_INVALID_FORMAT );
1394 PK_VALIDATE_RET( key != NULL || keylen == 0 );
1395
1396 #if defined(MBEDTLS_PEM_PARSE_C)
1397 mbedtls_pem_init( &pem );
1398 #if defined(MBEDTLS_RSA_C)
1399 /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
1400 if( key[keylen - 1] != '\0' )
1401 ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
1402 else
1403 ret = mbedtls_pem_read_buffer( &pem,
1404 "-----BEGIN RSA PUBLIC KEY-----",
1405 "-----END RSA PUBLIC KEY-----",
1406 key, NULL, 0, &len );
1407
1408 if( ret == 0 )
1409 {
1410 p = pem.buf;
1411 if( ( pk_info = mbedtls_pk_info_from_type( MBEDTLS_PK_RSA ) ) == NULL )
1412 return( MBEDTLS_ERR_PK_UNKNOWN_PK_ALG );
1413
1414 if( ( ret = mbedtls_pk_setup( ctx, pk_info ) ) != 0 )
1415 return( ret );
1416
1417 if ( ( ret = pk_get_rsapubkey( &p, p + pem.buflen, mbedtls_pk_rsa( *ctx ) ) ) != 0 )
1418 mbedtls_pk_free( ctx );
1419
1420 mbedtls_pem_free( &pem );
1421 return( ret );
1422 }
1423 else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
1424 {
1425 mbedtls_pem_free( &pem );
1426 return( ret );
1427 }
1428 #endif /* MBEDTLS_RSA_C */
1429
1430 /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */
1431 if( key[keylen - 1] != '\0' )
1432 ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT;
1433 else
1434 ret = mbedtls_pem_read_buffer( &pem,
1435 "-----BEGIN PUBLIC KEY-----",
1436 "-----END PUBLIC KEY-----",
1437 key, NULL, 0, &len );
1438
1439 if( ret == 0 )
1440 {
1441 /*
1442 * Was PEM encoded
1443 */
1444 p = pem.buf;
1445
1446 ret = mbedtls_pk_parse_subpubkey( &p, p + pem.buflen, ctx );
1447 mbedtls_pem_free( &pem );
1448 return( ret );
1449 }
1450 else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT )
1451 {
1452 mbedtls_pem_free( &pem );
1453 return( ret );
1454 }
1455 mbedtls_pem_free( &pem );
1456 #endif /* MBEDTLS_PEM_PARSE_C */
1457
1458 #if defined(MBEDTLS_RSA_C)
1459 if( ( pk_info = mbedtls_pk_info_from_type( MBEDTLS_PK_RSA ) ) == NULL )
1460 return( MBEDTLS_ERR_PK_UNKNOWN_PK_ALG );
1461
1462 if( ( ret = mbedtls_pk_setup( ctx, pk_info ) ) != 0 )
1463 return( ret );
1464
1465 p = (unsigned char *)key;
1466 ret = pk_get_rsapubkey( &p, p + keylen, mbedtls_pk_rsa( *ctx ) );
1467 if( ret == 0 )
1468 {
1469 return( ret );
1470 }
1471 mbedtls_pk_free( ctx );
1472 if( ret != ( MBEDTLS_ERR_PK_INVALID_PUBKEY + MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) )
1473 {
1474 return( ret );
1475 }
1476 #endif /* MBEDTLS_RSA_C */
1477 p = (unsigned char *) key;
1478
1479 ret = mbedtls_pk_parse_subpubkey( &p, p + keylen, ctx );
1480
1481 return( ret );
1482 }
1483
1484 #endif /* MBEDTLS_PK_PARSE_C */
1485