0,0 → 1,568 |
/* |
* Public Key layer for writing key files and structures |
* |
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved |
* SPDX-License-Identifier: GPL-2.0 |
* |
* This program is free software; you can redistribute it and/or modify |
* it under the terms of the GNU General Public License as published by |
* the Free Software Foundation; either version 2 of the License, or |
* (at your option) any later version. |
* |
* This program is distributed in the hope that it will be useful, |
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
* GNU General Public License for more details. |
* |
* You should have received a copy of the GNU General Public License along |
* with this program; if not, write to the Free Software Foundation, Inc., |
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
* |
* This file is part of mbed TLS (https://tls.mbed.org) |
*/ |
|
#if !defined(MBEDTLS_CONFIG_FILE) |
#include "mbedtls/config.h" |
#else |
#include MBEDTLS_CONFIG_FILE |
#endif |
|
#if defined(MBEDTLS_PK_WRITE_C) |
|
#include "mbedtls/pk.h" |
#include "mbedtls/asn1write.h" |
#include "mbedtls/oid.h" |
#include "mbedtls/platform_util.h" |
|
#include <string.h> |
|
#if defined(MBEDTLS_RSA_C) |
#include "mbedtls/rsa.h" |
#endif |
#if defined(MBEDTLS_ECP_C) |
#include "mbedtls/bignum.h" |
#include "mbedtls/ecp.h" |
#include "mbedtls/platform_util.h" |
#endif |
#if defined(MBEDTLS_ECDSA_C) |
#include "mbedtls/ecdsa.h" |
#endif |
#if defined(MBEDTLS_PEM_WRITE_C) |
#include "mbedtls/pem.h" |
#endif |
|
#if defined(MBEDTLS_PLATFORM_C) |
#include "mbedtls/platform.h" |
#else |
#include <stdlib.h> |
#define mbedtls_calloc calloc |
#define mbedtls_free free |
#endif |
|
/* Parameter validation macros based on platform_util.h */ |
#define PK_VALIDATE_RET( cond ) \ |
MBEDTLS_INTERNAL_VALIDATE_RET( cond, MBEDTLS_ERR_PK_BAD_INPUT_DATA ) |
#define PK_VALIDATE( cond ) \ |
MBEDTLS_INTERNAL_VALIDATE( cond ) |
|
#if defined(MBEDTLS_RSA_C) |
/* |
* RSAPublicKey ::= SEQUENCE { |
* modulus INTEGER, -- n |
* publicExponent INTEGER -- e |
* } |
*/ |
static int pk_write_rsa_pubkey( unsigned char **p, unsigned char *start, |
mbedtls_rsa_context *rsa ) |
{ |
int ret; |
size_t len = 0; |
mbedtls_mpi T; |
|
mbedtls_mpi_init( &T ); |
|
/* Export E */ |
if ( ( ret = mbedtls_rsa_export( rsa, NULL, NULL, NULL, NULL, &T ) ) != 0 || |
( ret = mbedtls_asn1_write_mpi( p, start, &T ) ) < 0 ) |
goto end_of_export; |
len += ret; |
|
/* Export N */ |
if ( ( ret = mbedtls_rsa_export( rsa, &T, NULL, NULL, NULL, NULL ) ) != 0 || |
( ret = mbedtls_asn1_write_mpi( p, start, &T ) ) < 0 ) |
goto end_of_export; |
len += ret; |
|
end_of_export: |
|
mbedtls_mpi_free( &T ); |
if( ret < 0 ) |
return( ret ); |
|
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( p, start, len ) ); |
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( p, start, MBEDTLS_ASN1_CONSTRUCTED | |
MBEDTLS_ASN1_SEQUENCE ) ); |
|
return( (int) len ); |
} |
#endif /* MBEDTLS_RSA_C */ |
|
#if defined(MBEDTLS_ECP_C) |
/* |
* EC public key is an EC point |
*/ |
static int pk_write_ec_pubkey( unsigned char **p, unsigned char *start, |
mbedtls_ecp_keypair *ec ) |
{ |
int ret; |
size_t len = 0; |
unsigned char buf[MBEDTLS_ECP_MAX_PT_LEN]; |
|
if( ( ret = mbedtls_ecp_point_write_binary( &ec->grp, &ec->Q, |
MBEDTLS_ECP_PF_UNCOMPRESSED, |
&len, buf, sizeof( buf ) ) ) != 0 ) |
{ |
return( ret ); |
} |
|
if( *p < start || (size_t)( *p - start ) < len ) |
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL ); |
|
*p -= len; |
memcpy( *p, buf, len ); |
|
return( (int) len ); |
} |
|
/* |
* ECParameters ::= CHOICE { |
* namedCurve OBJECT IDENTIFIER |
* } |
*/ |
static int pk_write_ec_param( unsigned char **p, unsigned char *start, |
mbedtls_ecp_keypair *ec ) |
{ |
int ret; |
size_t len = 0; |
const char *oid; |
size_t oid_len; |
|
if( ( ret = mbedtls_oid_get_oid_by_ec_grp( ec->grp.id, &oid, &oid_len ) ) != 0 ) |
return( ret ); |
|
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_oid( p, start, oid, oid_len ) ); |
|
return( (int) len ); |
} |
|
/* |
* privateKey OCTET STRING -- always of length ceil(log2(n)/8) |
*/ |
static int pk_write_ec_private( unsigned char **p, unsigned char *start, |
mbedtls_ecp_keypair *ec ) |
{ |
int ret; |
size_t byte_length = ( ec->grp.pbits + 7 ) / 8; |
unsigned char tmp[MBEDTLS_ECP_MAX_BYTES]; |
|
ret = mbedtls_mpi_write_binary( &ec->d, tmp, byte_length ); |
if( ret != 0 ) |
goto exit; |
ret = mbedtls_asn1_write_octet_string( p, start, tmp, byte_length ); |
|
exit: |
mbedtls_platform_zeroize( tmp, byte_length ); |
return( ret ); |
} |
#endif /* MBEDTLS_ECP_C */ |
|
int mbedtls_pk_write_pubkey( unsigned char **p, unsigned char *start, |
const mbedtls_pk_context *key ) |
{ |
int ret; |
size_t len = 0; |
|
PK_VALIDATE_RET( p != NULL ); |
PK_VALIDATE_RET( *p != NULL ); |
PK_VALIDATE_RET( start != NULL ); |
PK_VALIDATE_RET( key != NULL ); |
|
#if defined(MBEDTLS_RSA_C) |
if( mbedtls_pk_get_type( key ) == MBEDTLS_PK_RSA ) |
MBEDTLS_ASN1_CHK_ADD( len, pk_write_rsa_pubkey( p, start, mbedtls_pk_rsa( *key ) ) ); |
else |
#endif |
#if defined(MBEDTLS_ECP_C) |
if( mbedtls_pk_get_type( key ) == MBEDTLS_PK_ECKEY ) |
MBEDTLS_ASN1_CHK_ADD( len, pk_write_ec_pubkey( p, start, mbedtls_pk_ec( *key ) ) ); |
else |
#endif |
return( MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE ); |
|
return( (int) len ); |
} |
|
int mbedtls_pk_write_pubkey_der( mbedtls_pk_context *key, unsigned char *buf, size_t size ) |
{ |
int ret; |
unsigned char *c; |
size_t len = 0, par_len = 0, oid_len; |
const char *oid; |
|
PK_VALIDATE_RET( key != NULL ); |
if( size == 0 ) |
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL ); |
PK_VALIDATE_RET( buf != NULL ); |
|
c = buf + size; |
|
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_pk_write_pubkey( &c, buf, key ) ); |
|
if( c - buf < 1 ) |
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL ); |
|
/* |
* SubjectPublicKeyInfo ::= SEQUENCE { |
* algorithm AlgorithmIdentifier, |
* subjectPublicKey BIT STRING } |
*/ |
*--c = 0; |
len += 1; |
|
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, buf, len ) ); |
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, buf, MBEDTLS_ASN1_BIT_STRING ) ); |
|
if( ( ret = mbedtls_oid_get_oid_by_pk_alg( mbedtls_pk_get_type( key ), |
&oid, &oid_len ) ) != 0 ) |
{ |
return( ret ); |
} |
|
#if defined(MBEDTLS_ECP_C) |
if( mbedtls_pk_get_type( key ) == MBEDTLS_PK_ECKEY ) |
{ |
MBEDTLS_ASN1_CHK_ADD( par_len, pk_write_ec_param( &c, buf, mbedtls_pk_ec( *key ) ) ); |
} |
#endif |
|
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_algorithm_identifier( &c, buf, oid, oid_len, |
par_len ) ); |
|
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, buf, len ) ); |
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, buf, MBEDTLS_ASN1_CONSTRUCTED | |
MBEDTLS_ASN1_SEQUENCE ) ); |
|
return( (int) len ); |
} |
|
int mbedtls_pk_write_key_der( mbedtls_pk_context *key, unsigned char *buf, size_t size ) |
{ |
int ret; |
unsigned char *c; |
size_t len = 0; |
|
PK_VALIDATE_RET( key != NULL ); |
if( size == 0 ) |
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL ); |
PK_VALIDATE_RET( buf != NULL ); |
|
c = buf + size; |
|
#if defined(MBEDTLS_RSA_C) |
if( mbedtls_pk_get_type( key ) == MBEDTLS_PK_RSA ) |
{ |
mbedtls_mpi T; /* Temporary holding the exported parameters */ |
mbedtls_rsa_context *rsa = mbedtls_pk_rsa( *key ); |
|
/* |
* Export the parameters one after another to avoid simultaneous copies. |
*/ |
|
mbedtls_mpi_init( &T ); |
|
/* Export QP */ |
if( ( ret = mbedtls_rsa_export_crt( rsa, NULL, NULL, &T ) ) != 0 || |
( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 ) |
goto end_of_export; |
len += ret; |
|
/* Export DQ */ |
if( ( ret = mbedtls_rsa_export_crt( rsa, NULL, &T, NULL ) ) != 0 || |
( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 ) |
goto end_of_export; |
len += ret; |
|
/* Export DP */ |
if( ( ret = mbedtls_rsa_export_crt( rsa, &T, NULL, NULL ) ) != 0 || |
( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 ) |
goto end_of_export; |
len += ret; |
|
/* Export Q */ |
if ( ( ret = mbedtls_rsa_export( rsa, NULL, NULL, |
&T, NULL, NULL ) ) != 0 || |
( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 ) |
goto end_of_export; |
len += ret; |
|
/* Export P */ |
if ( ( ret = mbedtls_rsa_export( rsa, NULL, &T, |
NULL, NULL, NULL ) ) != 0 || |
( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 ) |
goto end_of_export; |
len += ret; |
|
/* Export D */ |
if ( ( ret = mbedtls_rsa_export( rsa, NULL, NULL, |
NULL, &T, NULL ) ) != 0 || |
( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 ) |
goto end_of_export; |
len += ret; |
|
/* Export E */ |
if ( ( ret = mbedtls_rsa_export( rsa, NULL, NULL, |
NULL, NULL, &T ) ) != 0 || |
( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 ) |
goto end_of_export; |
len += ret; |
|
/* Export N */ |
if ( ( ret = mbedtls_rsa_export( rsa, &T, NULL, |
NULL, NULL, NULL ) ) != 0 || |
( ret = mbedtls_asn1_write_mpi( &c, buf, &T ) ) < 0 ) |
goto end_of_export; |
len += ret; |
|
end_of_export: |
|
mbedtls_mpi_free( &T ); |
if( ret < 0 ) |
return( ret ); |
|
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_int( &c, buf, 0 ) ); |
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, buf, len ) ); |
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, |
buf, MBEDTLS_ASN1_CONSTRUCTED | |
MBEDTLS_ASN1_SEQUENCE ) ); |
} |
else |
#endif /* MBEDTLS_RSA_C */ |
#if defined(MBEDTLS_ECP_C) |
if( mbedtls_pk_get_type( key ) == MBEDTLS_PK_ECKEY ) |
{ |
mbedtls_ecp_keypair *ec = mbedtls_pk_ec( *key ); |
size_t pub_len = 0, par_len = 0; |
|
/* |
* RFC 5915, or SEC1 Appendix C.4 |
* |
* ECPrivateKey ::= SEQUENCE { |
* version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1), |
* privateKey OCTET STRING, |
* parameters [0] ECParameters {{ NamedCurve }} OPTIONAL, |
* publicKey [1] BIT STRING OPTIONAL |
* } |
*/ |
|
/* publicKey */ |
MBEDTLS_ASN1_CHK_ADD( pub_len, pk_write_ec_pubkey( &c, buf, ec ) ); |
|
if( c - buf < 1 ) |
return( MBEDTLS_ERR_ASN1_BUF_TOO_SMALL ); |
*--c = 0; |
pub_len += 1; |
|
MBEDTLS_ASN1_CHK_ADD( pub_len, mbedtls_asn1_write_len( &c, buf, pub_len ) ); |
MBEDTLS_ASN1_CHK_ADD( pub_len, mbedtls_asn1_write_tag( &c, buf, MBEDTLS_ASN1_BIT_STRING ) ); |
|
MBEDTLS_ASN1_CHK_ADD( pub_len, mbedtls_asn1_write_len( &c, buf, pub_len ) ); |
MBEDTLS_ASN1_CHK_ADD( pub_len, mbedtls_asn1_write_tag( &c, buf, |
MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 1 ) ); |
len += pub_len; |
|
/* parameters */ |
MBEDTLS_ASN1_CHK_ADD( par_len, pk_write_ec_param( &c, buf, ec ) ); |
|
MBEDTLS_ASN1_CHK_ADD( par_len, mbedtls_asn1_write_len( &c, buf, par_len ) ); |
MBEDTLS_ASN1_CHK_ADD( par_len, mbedtls_asn1_write_tag( &c, buf, |
MBEDTLS_ASN1_CONTEXT_SPECIFIC | MBEDTLS_ASN1_CONSTRUCTED | 0 ) ); |
len += par_len; |
|
/* privateKey */ |
MBEDTLS_ASN1_CHK_ADD( len, pk_write_ec_private( &c, buf, ec ) ); |
|
/* version */ |
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_int( &c, buf, 1 ) ); |
|
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_len( &c, buf, len ) ); |
MBEDTLS_ASN1_CHK_ADD( len, mbedtls_asn1_write_tag( &c, buf, MBEDTLS_ASN1_CONSTRUCTED | |
MBEDTLS_ASN1_SEQUENCE ) ); |
} |
else |
#endif /* MBEDTLS_ECP_C */ |
return( MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE ); |
|
return( (int) len ); |
} |
|
#if defined(MBEDTLS_PEM_WRITE_C) |
|
#define PEM_BEGIN_PUBLIC_KEY "-----BEGIN PUBLIC KEY-----\n" |
#define PEM_END_PUBLIC_KEY "-----END PUBLIC KEY-----\n" |
|
#define PEM_BEGIN_PRIVATE_KEY_RSA "-----BEGIN RSA PRIVATE KEY-----\n" |
#define PEM_END_PRIVATE_KEY_RSA "-----END RSA PRIVATE KEY-----\n" |
#define PEM_BEGIN_PRIVATE_KEY_EC "-----BEGIN EC PRIVATE KEY-----\n" |
#define PEM_END_PRIVATE_KEY_EC "-----END EC PRIVATE KEY-----\n" |
|
/* |
* Max sizes of key per types. Shown as tag + len (+ content). |
*/ |
|
#if defined(MBEDTLS_RSA_C) |
/* |
* RSA public keys: |
* SubjectPublicKeyInfo ::= SEQUENCE { 1 + 3 |
* algorithm AlgorithmIdentifier, 1 + 1 (sequence) |
* + 1 + 1 + 9 (rsa oid) |
* + 1 + 1 (params null) |
* subjectPublicKey BIT STRING } 1 + 3 + (1 + below) |
* RSAPublicKey ::= SEQUENCE { 1 + 3 |
* modulus INTEGER, -- n 1 + 3 + MPI_MAX + 1 |
* publicExponent INTEGER -- e 1 + 3 + MPI_MAX + 1 |
* } |
*/ |
#define RSA_PUB_DER_MAX_BYTES 38 + 2 * MBEDTLS_MPI_MAX_SIZE |
|
/* |
* RSA private keys: |
* RSAPrivateKey ::= SEQUENCE { 1 + 3 |
* version Version, 1 + 1 + 1 |
* modulus INTEGER, 1 + 3 + MPI_MAX + 1 |
* publicExponent INTEGER, 1 + 3 + MPI_MAX + 1 |
* privateExponent INTEGER, 1 + 3 + MPI_MAX + 1 |
* prime1 INTEGER, 1 + 3 + MPI_MAX / 2 + 1 |
* prime2 INTEGER, 1 + 3 + MPI_MAX / 2 + 1 |
* exponent1 INTEGER, 1 + 3 + MPI_MAX / 2 + 1 |
* exponent2 INTEGER, 1 + 3 + MPI_MAX / 2 + 1 |
* coefficient INTEGER, 1 + 3 + MPI_MAX / 2 + 1 |
* otherPrimeInfos OtherPrimeInfos OPTIONAL 0 (not supported) |
* } |
*/ |
#define MPI_MAX_SIZE_2 MBEDTLS_MPI_MAX_SIZE / 2 + \ |
MBEDTLS_MPI_MAX_SIZE % 2 |
#define RSA_PRV_DER_MAX_BYTES 47 + 3 * MBEDTLS_MPI_MAX_SIZE \ |
+ 5 * MPI_MAX_SIZE_2 |
|
#else /* MBEDTLS_RSA_C */ |
|
#define RSA_PUB_DER_MAX_BYTES 0 |
#define RSA_PRV_DER_MAX_BYTES 0 |
|
#endif /* MBEDTLS_RSA_C */ |
|
#if defined(MBEDTLS_ECP_C) |
/* |
* EC public keys: |
* SubjectPublicKeyInfo ::= SEQUENCE { 1 + 2 |
* algorithm AlgorithmIdentifier, 1 + 1 (sequence) |
* + 1 + 1 + 7 (ec oid) |
* + 1 + 1 + 9 (namedCurve oid) |
* subjectPublicKey BIT STRING 1 + 2 + 1 [1] |
* + 1 (point format) [1] |
* + 2 * ECP_MAX (coords) [1] |
* } |
*/ |
#define ECP_PUB_DER_MAX_BYTES 30 + 2 * MBEDTLS_ECP_MAX_BYTES |
|
/* |
* EC private keys: |
* ECPrivateKey ::= SEQUENCE { 1 + 2 |
* version INTEGER , 1 + 1 + 1 |
* privateKey OCTET STRING, 1 + 1 + ECP_MAX |
* parameters [0] ECParameters OPTIONAL, 1 + 1 + (1 + 1 + 9) |
* publicKey [1] BIT STRING OPTIONAL 1 + 2 + [1] above |
* } |
*/ |
#define ECP_PRV_DER_MAX_BYTES 29 + 3 * MBEDTLS_ECP_MAX_BYTES |
|
#else /* MBEDTLS_ECP_C */ |
|
#define ECP_PUB_DER_MAX_BYTES 0 |
#define ECP_PRV_DER_MAX_BYTES 0 |
|
#endif /* MBEDTLS_ECP_C */ |
|
#define PUB_DER_MAX_BYTES RSA_PUB_DER_MAX_BYTES > ECP_PUB_DER_MAX_BYTES ? \ |
RSA_PUB_DER_MAX_BYTES : ECP_PUB_DER_MAX_BYTES |
#define PRV_DER_MAX_BYTES RSA_PRV_DER_MAX_BYTES > ECP_PRV_DER_MAX_BYTES ? \ |
RSA_PRV_DER_MAX_BYTES : ECP_PRV_DER_MAX_BYTES |
|
int mbedtls_pk_write_pubkey_pem( mbedtls_pk_context *key, unsigned char *buf, size_t size ) |
{ |
int ret; |
unsigned char output_buf[PUB_DER_MAX_BYTES]; |
size_t olen = 0; |
|
PK_VALIDATE_RET( key != NULL ); |
PK_VALIDATE_RET( buf != NULL || size == 0 ); |
|
if( ( ret = mbedtls_pk_write_pubkey_der( key, output_buf, |
sizeof(output_buf) ) ) < 0 ) |
{ |
return( ret ); |
} |
|
if( ( ret = mbedtls_pem_write_buffer( PEM_BEGIN_PUBLIC_KEY, PEM_END_PUBLIC_KEY, |
output_buf + sizeof(output_buf) - ret, |
ret, buf, size, &olen ) ) != 0 ) |
{ |
return( ret ); |
} |
|
return( 0 ); |
} |
|
int mbedtls_pk_write_key_pem( mbedtls_pk_context *key, unsigned char *buf, size_t size ) |
{ |
int ret; |
unsigned char output_buf[PRV_DER_MAX_BYTES]; |
const char *begin, *end; |
size_t olen = 0; |
|
PK_VALIDATE_RET( key != NULL ); |
PK_VALIDATE_RET( buf != NULL || size == 0 ); |
|
if( ( ret = mbedtls_pk_write_key_der( key, output_buf, sizeof(output_buf) ) ) < 0 ) |
return( ret ); |
|
#if defined(MBEDTLS_RSA_C) |
if( mbedtls_pk_get_type( key ) == MBEDTLS_PK_RSA ) |
{ |
begin = PEM_BEGIN_PRIVATE_KEY_RSA; |
end = PEM_END_PRIVATE_KEY_RSA; |
} |
else |
#endif |
#if defined(MBEDTLS_ECP_C) |
if( mbedtls_pk_get_type( key ) == MBEDTLS_PK_ECKEY ) |
{ |
begin = PEM_BEGIN_PRIVATE_KEY_EC; |
end = PEM_END_PRIVATE_KEY_EC; |
} |
else |
#endif |
return( MBEDTLS_ERR_PK_FEATURE_UNAVAILABLE ); |
|
if( ( ret = mbedtls_pem_write_buffer( begin, end, |
output_buf + sizeof(output_buf) - ret, |
ret, buf, size, &olen ) ) != 0 ) |
{ |
return( ret ); |
} |
|
return( 0 ); |
} |
#endif /* MBEDTLS_PEM_WRITE_C */ |
|
#endif /* MBEDTLS_PK_WRITE_C */ |