440 lines
14 KiB
C
440 lines
14 KiB
C
/*
|
|
* Public Key layer for writing key files and structures
|
|
*
|
|
* Copyright (C) 2006-2014, ARM Limited, All Rights Reserved
|
|
*
|
|
* This file is part of mbed TLS (http://www.polarssl.org)
|
|
* Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#if !defined(POLARSSL_CONFIG_FILE)
|
|
#include "polarssl/config.h"
|
|
#else
|
|
#include POLARSSL_CONFIG_FILE
|
|
#endif
|
|
|
|
#if defined(POLARSSL_PK_WRITE_C)
|
|
|
|
#include "polarssl/pk.h"
|
|
#include "polarssl/asn1write.h"
|
|
#include "polarssl/oid.h"
|
|
|
|
#if defined(POLARSSL_RSA_C)
|
|
#include "polarssl/rsa.h"
|
|
#endif
|
|
#if defined(POLARSSL_ECP_C)
|
|
#include "polarssl/ecp.h"
|
|
#endif
|
|
#if defined(POLARSSL_ECDSA_C)
|
|
#include "polarssl/ecdsa.h"
|
|
#endif
|
|
#if defined(POLARSSL_PEM_WRITE_C)
|
|
#include "polarssl/pem.h"
|
|
#endif
|
|
|
|
#if defined(POLARSSL_PLATFORM_C)
|
|
#include "polarssl/platform.h"
|
|
#else
|
|
#include <stdlib.h>
|
|
#define polarssl_malloc malloc
|
|
#define polarssl_free free
|
|
#endif
|
|
|
|
#if defined(POLARSSL_RSA_C)
|
|
/*
|
|
* RSAPublicKey ::= SEQUENCE {
|
|
* modulus INTEGER, -- n
|
|
* publicExponent INTEGER -- e
|
|
* }
|
|
*/
|
|
static int pk_write_rsa_pubkey( unsigned char **p, unsigned char *start,
|
|
rsa_context *rsa )
|
|
{
|
|
int ret;
|
|
size_t len = 0;
|
|
|
|
ASN1_CHK_ADD( len, asn1_write_mpi( p, start, &rsa->E ) );
|
|
ASN1_CHK_ADD( len, asn1_write_mpi( p, start, &rsa->N ) );
|
|
|
|
ASN1_CHK_ADD( len, asn1_write_len( p, start, len ) );
|
|
ASN1_CHK_ADD( len, asn1_write_tag( p, start, ASN1_CONSTRUCTED |
|
|
ASN1_SEQUENCE ) );
|
|
|
|
return( (int) len );
|
|
}
|
|
#endif /* POLARSSL_RSA_C */
|
|
|
|
#if defined(POLARSSL_ECP_C)
|
|
/*
|
|
* EC public key is an EC point
|
|
*/
|
|
static int pk_write_ec_pubkey( unsigned char **p, unsigned char *start,
|
|
ecp_keypair *ec )
|
|
{
|
|
int ret;
|
|
size_t len = 0;
|
|
unsigned char buf[POLARSSL_ECP_MAX_PT_LEN];
|
|
|
|
if( ( ret = ecp_point_write_binary( &ec->grp, &ec->Q,
|
|
POLARSSL_ECP_PF_UNCOMPRESSED,
|
|
&len, buf, sizeof( buf ) ) ) != 0 )
|
|
{
|
|
return( ret );
|
|
}
|
|
|
|
if( *p - start < (int) len )
|
|
return( POLARSSL_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,
|
|
ecp_keypair *ec )
|
|
{
|
|
int ret;
|
|
size_t len = 0;
|
|
const char *oid;
|
|
size_t oid_len;
|
|
|
|
if( ( ret = oid_get_oid_by_ec_grp( ec->grp.id, &oid, &oid_len ) ) != 0 )
|
|
return( ret );
|
|
|
|
ASN1_CHK_ADD( len, asn1_write_oid( p, start, oid, oid_len ) );
|
|
|
|
return( (int) len );
|
|
}
|
|
#endif /* POLARSSL_ECP_C */
|
|
|
|
int pk_write_pubkey( unsigned char **p, unsigned char *start,
|
|
const pk_context *key )
|
|
{
|
|
int ret;
|
|
size_t len = 0;
|
|
|
|
#if defined(POLARSSL_RSA_C)
|
|
if( pk_get_type( key ) == POLARSSL_PK_RSA )
|
|
ASN1_CHK_ADD( len, pk_write_rsa_pubkey( p, start, pk_rsa( *key ) ) );
|
|
else
|
|
#endif
|
|
#if defined(POLARSSL_ECP_C)
|
|
if( pk_get_type( key ) == POLARSSL_PK_ECKEY )
|
|
ASN1_CHK_ADD( len, pk_write_ec_pubkey( p, start, pk_ec( *key ) ) );
|
|
else
|
|
#endif
|
|
return( POLARSSL_ERR_PK_FEATURE_UNAVAILABLE );
|
|
|
|
return( (int) len );
|
|
}
|
|
|
|
int pk_write_pubkey_der( 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;
|
|
|
|
c = buf + size;
|
|
|
|
ASN1_CHK_ADD( len, pk_write_pubkey( &c, buf, key ) );
|
|
|
|
if( c - buf < 1 )
|
|
return( POLARSSL_ERR_ASN1_BUF_TOO_SMALL );
|
|
|
|
/*
|
|
* SubjectPublicKeyInfo ::= SEQUENCE {
|
|
* algorithm AlgorithmIdentifier,
|
|
* subjectPublicKey BIT STRING }
|
|
*/
|
|
*--c = 0;
|
|
len += 1;
|
|
|
|
ASN1_CHK_ADD( len, asn1_write_len( &c, buf, len ) );
|
|
ASN1_CHK_ADD( len, asn1_write_tag( &c, buf, ASN1_BIT_STRING ) );
|
|
|
|
if( ( ret = oid_get_oid_by_pk_alg( pk_get_type( key ),
|
|
&oid, &oid_len ) ) != 0 )
|
|
{
|
|
return( ret );
|
|
}
|
|
|
|
#if defined(POLARSSL_ECP_C)
|
|
if( pk_get_type( key ) == POLARSSL_PK_ECKEY )
|
|
{
|
|
ASN1_CHK_ADD( par_len, pk_write_ec_param( &c, buf, pk_ec( *key ) ) );
|
|
}
|
|
#endif
|
|
|
|
ASN1_CHK_ADD( len, asn1_write_algorithm_identifier( &c, buf, oid, oid_len,
|
|
par_len ) );
|
|
|
|
ASN1_CHK_ADD( len, asn1_write_len( &c, buf, len ) );
|
|
ASN1_CHK_ADD( len, asn1_write_tag( &c, buf, ASN1_CONSTRUCTED |
|
|
ASN1_SEQUENCE ) );
|
|
|
|
return( (int) len );
|
|
}
|
|
|
|
int pk_write_key_der( pk_context *key, unsigned char *buf, size_t size )
|
|
{
|
|
int ret;
|
|
unsigned char *c = buf + size;
|
|
size_t len = 0;
|
|
|
|
#if defined(POLARSSL_RSA_C)
|
|
if( pk_get_type( key ) == POLARSSL_PK_RSA )
|
|
{
|
|
rsa_context *rsa = pk_rsa( *key );
|
|
|
|
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->QP ) );
|
|
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->DQ ) );
|
|
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->DP ) );
|
|
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->Q ) );
|
|
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->P ) );
|
|
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->D ) );
|
|
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->E ) );
|
|
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &rsa->N ) );
|
|
ASN1_CHK_ADD( len, asn1_write_int( &c, buf, 0 ) );
|
|
|
|
ASN1_CHK_ADD( len, asn1_write_len( &c, buf, len ) );
|
|
ASN1_CHK_ADD( len, asn1_write_tag( &c, buf, ASN1_CONSTRUCTED |
|
|
ASN1_SEQUENCE ) );
|
|
}
|
|
else
|
|
#endif /* POLARSSL_RSA_C */
|
|
#if defined(POLARSSL_ECP_C)
|
|
if( pk_get_type( key ) == POLARSSL_PK_ECKEY )
|
|
{
|
|
ecp_keypair *ec = 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 */
|
|
ASN1_CHK_ADD( pub_len, pk_write_ec_pubkey( &c, buf, ec ) );
|
|
|
|
if( c - buf < 1 )
|
|
return( POLARSSL_ERR_ASN1_BUF_TOO_SMALL );
|
|
*--c = 0;
|
|
pub_len += 1;
|
|
|
|
ASN1_CHK_ADD( pub_len, asn1_write_len( &c, buf, pub_len ) );
|
|
ASN1_CHK_ADD( pub_len, asn1_write_tag( &c, buf, ASN1_BIT_STRING ) );
|
|
|
|
ASN1_CHK_ADD( pub_len, asn1_write_len( &c, buf, pub_len ) );
|
|
ASN1_CHK_ADD( pub_len, asn1_write_tag( &c, buf,
|
|
ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 1 ) );
|
|
len += pub_len;
|
|
|
|
/* parameters */
|
|
ASN1_CHK_ADD( par_len, pk_write_ec_param( &c, buf, ec ) );
|
|
|
|
ASN1_CHK_ADD( par_len, asn1_write_len( &c, buf, par_len ) );
|
|
ASN1_CHK_ADD( par_len, asn1_write_tag( &c, buf,
|
|
ASN1_CONTEXT_SPECIFIC | ASN1_CONSTRUCTED | 0 ) );
|
|
len += par_len;
|
|
|
|
/* privateKey: write as MPI then fix tag */
|
|
ASN1_CHK_ADD( len, asn1_write_mpi( &c, buf, &ec->d ) );
|
|
*c = ASN1_OCTET_STRING;
|
|
|
|
/* version */
|
|
ASN1_CHK_ADD( len, asn1_write_int( &c, buf, 1 ) );
|
|
|
|
ASN1_CHK_ADD( len, asn1_write_len( &c, buf, len ) );
|
|
ASN1_CHK_ADD( len, asn1_write_tag( &c, buf, ASN1_CONSTRUCTED |
|
|
ASN1_SEQUENCE ) );
|
|
}
|
|
else
|
|
#endif /* POLARSSL_ECP_C */
|
|
return( POLARSSL_ERR_PK_FEATURE_UNAVAILABLE );
|
|
|
|
return( (int) len );
|
|
}
|
|
|
|
#if defined(POLARSSL_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(POLARSSL_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 * POLARSSL_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 POLARSSL_MPI_MAX_SIZE / 2 + \
|
|
POLARSSL_MPI_MAX_SIZE % 2
|
|
#define RSA_PRV_DER_MAX_BYTES 47 + 3 * POLARSSL_MPI_MAX_SIZE \
|
|
+ 5 * MPI_MAX_SIZE_2
|
|
|
|
#else /* POLARSSL_RSA_C */
|
|
|
|
#define RSA_PUB_DER_MAX_BYTES 0
|
|
#define RSA_PRV_DER_MAX_BYTES 0
|
|
|
|
#endif /* POLARSSL_RSA_C */
|
|
|
|
#if defined(POLARSSL_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 * POLARSSL_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 * POLARSSL_ECP_MAX_BYTES
|
|
|
|
#else /* POLARSSL_ECP_C */
|
|
|
|
#define ECP_PUB_DER_MAX_BYTES 0
|
|
#define ECP_PRV_DER_MAX_BYTES 0
|
|
|
|
#endif /* POLARSSL_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 pk_write_pubkey_pem( pk_context *key, unsigned char *buf, size_t size )
|
|
{
|
|
int ret;
|
|
unsigned char output_buf[PUB_DER_MAX_BYTES];
|
|
size_t olen = 0;
|
|
|
|
if( ( ret = pk_write_pubkey_der( key, output_buf,
|
|
sizeof(output_buf) ) ) < 0 )
|
|
{
|
|
return( ret );
|
|
}
|
|
|
|
if( ( ret = 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 pk_write_key_pem( 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;
|
|
|
|
if( ( ret = pk_write_key_der( key, output_buf, sizeof(output_buf) ) ) < 0 )
|
|
return( ret );
|
|
|
|
#if defined(POLARSSL_RSA_C)
|
|
if( pk_get_type( key ) == POLARSSL_PK_RSA )
|
|
{
|
|
begin = PEM_BEGIN_PRIVATE_KEY_RSA;
|
|
end = PEM_END_PRIVATE_KEY_RSA;
|
|
}
|
|
else
|
|
#endif
|
|
#if defined(POLARSSL_ECP_C)
|
|
if( pk_get_type( key ) == POLARSSL_PK_ECKEY )
|
|
{
|
|
begin = PEM_BEGIN_PRIVATE_KEY_EC;
|
|
end = PEM_END_PRIVATE_KEY_EC;
|
|
}
|
|
else
|
|
#endif
|
|
return( POLARSSL_ERR_PK_FEATURE_UNAVAILABLE );
|
|
|
|
if( ( ret = pem_write_buffer( begin, end,
|
|
output_buf + sizeof(output_buf) - ret,
|
|
ret, buf, size, &olen ) ) != 0 )
|
|
{
|
|
return( ret );
|
|
}
|
|
|
|
return( 0 );
|
|
}
|
|
#endif /* POLARSSL_PEM_WRITE_C */
|
|
|
|
#endif /* POLARSSL_PK_WRITE_C */
|