mbedtls/library/pkcs12.c
Joe Subbiani fbeb692dd0 Use byte reading macros in places not using a byte mask
byte shifting opertations throughout library/ were only replaced with
the byte reading macros when an 0xff mask was being used.
The byte reading macros are now more widley used, however they have not
been used in all cases of a byte shift operation, as it detracted from
the immediate readability or otherwise did not seem appropriate.

Signed-off-by: Joe Subbiani <joe.subbiani@arm.com>
2021-08-19 09:56:47 +01:00

315 lines
9.5 KiB
C

/*
* PKCS#12 Personal Information Exchange Syntax
*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* The PKCS #12 Personal Information Exchange Syntax Standard v1.1
*
* http://www.rsa.com/rsalabs/pkcs/files/h11301-wp-pkcs-12v1-1-personal-information-exchange-syntax.pdf
* ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-12/pkcs-12v1-1.asn
*/
#include "common.h"
#if defined(MBEDTLS_PKCS12_C)
#include "mbedtls/pkcs12.h"
#include "mbedtls/asn1.h"
#include "mbedtls/cipher.h"
#include "mbedtls/platform_util.h"
#include "mbedtls/error.h"
#include <string.h>
#if defined(MBEDTLS_DES_C)
#include "mbedtls/des.h"
#endif
#if defined(MBEDTLS_ASN1_PARSE_C)
static int pkcs12_parse_pbe_params( mbedtls_asn1_buf *params,
mbedtls_asn1_buf *salt, int *iterations )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char **p = &params->p;
const unsigned char *end = params->p + params->len;
/*
* pkcs-12PbeParams ::= SEQUENCE {
* salt OCTET STRING,
* iterations INTEGER
* }
*
*/
if( params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT,
MBEDTLS_ERR_ASN1_UNEXPECTED_TAG ) );
if( ( ret = mbedtls_asn1_get_tag( p, end, &salt->len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT, ret ) );
salt->p = *p;
*p += salt->len;
if( ( ret = mbedtls_asn1_get_int( p, end, iterations ) ) != 0 )
return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT, ret ) );
if( *p != end )
return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT,
MBEDTLS_ERR_ASN1_LENGTH_MISMATCH ) );
return( 0 );
}
#define PKCS12_MAX_PWDLEN 128
static int pkcs12_pbe_derive_key_iv( mbedtls_asn1_buf *pbe_params, mbedtls_md_type_t md_type,
const unsigned char *pwd, size_t pwdlen,
unsigned char *key, size_t keylen,
unsigned char *iv, size_t ivlen )
{
int ret, iterations = 0;
mbedtls_asn1_buf salt;
size_t i;
unsigned char unipwd[PKCS12_MAX_PWDLEN * 2 + 2];
if( pwdlen > PKCS12_MAX_PWDLEN )
return( MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA );
memset( &salt, 0, sizeof(mbedtls_asn1_buf) );
memset( &unipwd, 0, sizeof(unipwd) );
if( ( ret = pkcs12_parse_pbe_params( pbe_params, &salt,
&iterations ) ) != 0 )
return( ret );
for( i = 0; i < pwdlen; i++ )
unipwd[i * 2 + 1] = pwd[i];
if( ( ret = mbedtls_pkcs12_derivation( key, keylen, unipwd, pwdlen * 2 + 2,
salt.p, salt.len, md_type,
MBEDTLS_PKCS12_DERIVE_KEY, iterations ) ) != 0 )
{
return( ret );
}
if( iv == NULL || ivlen == 0 )
return( 0 );
if( ( ret = mbedtls_pkcs12_derivation( iv, ivlen, unipwd, pwdlen * 2 + 2,
salt.p, salt.len, md_type,
MBEDTLS_PKCS12_DERIVE_IV, iterations ) ) != 0 )
{
return( ret );
}
return( 0 );
}
#undef PKCS12_MAX_PWDLEN
int mbedtls_pkcs12_pbe( mbedtls_asn1_buf *pbe_params, int mode,
mbedtls_cipher_type_t cipher_type, mbedtls_md_type_t md_type,
const unsigned char *pwd, size_t pwdlen,
const unsigned char *data, size_t len,
unsigned char *output )
{
int ret, keylen = 0;
unsigned char key[32];
unsigned char iv[16];
const mbedtls_cipher_info_t *cipher_info;
mbedtls_cipher_context_t cipher_ctx;
size_t olen = 0;
cipher_info = mbedtls_cipher_info_from_type( cipher_type );
if( cipher_info == NULL )
return( MBEDTLS_ERR_PKCS12_FEATURE_UNAVAILABLE );
keylen = cipher_info->key_bitlen / 8;
if( ( ret = pkcs12_pbe_derive_key_iv( pbe_params, md_type, pwd, pwdlen,
key, keylen,
iv, cipher_info->iv_size ) ) != 0 )
{
return( ret );
}
mbedtls_cipher_init( &cipher_ctx );
if( ( ret = mbedtls_cipher_setup( &cipher_ctx, cipher_info ) ) != 0 )
goto exit;
if( ( ret = mbedtls_cipher_setkey( &cipher_ctx, key, 8 * keylen, (mbedtls_operation_t) mode ) ) != 0 )
goto exit;
if( ( ret = mbedtls_cipher_set_iv( &cipher_ctx, iv, cipher_info->iv_size ) ) != 0 )
goto exit;
if( ( ret = mbedtls_cipher_reset( &cipher_ctx ) ) != 0 )
goto exit;
if( ( ret = mbedtls_cipher_update( &cipher_ctx, data, len,
output, &olen ) ) != 0 )
{
goto exit;
}
if( ( ret = mbedtls_cipher_finish( &cipher_ctx, output + olen, &olen ) ) != 0 )
ret = MBEDTLS_ERR_PKCS12_PASSWORD_MISMATCH;
exit:
mbedtls_platform_zeroize( key, sizeof( key ) );
mbedtls_platform_zeroize( iv, sizeof( iv ) );
mbedtls_cipher_free( &cipher_ctx );
return( ret );
}
#endif /* MBEDTLS_ASN1_PARSE_C */
static void pkcs12_fill_buffer( unsigned char *data, size_t data_len,
const unsigned char *filler, size_t fill_len )
{
unsigned char *p = data;
size_t use_len;
while( data_len > 0 )
{
use_len = ( data_len > fill_len ) ? fill_len : data_len;
memcpy( p, filler, use_len );
p += use_len;
data_len -= use_len;
}
}
int mbedtls_pkcs12_derivation( unsigned char *data, size_t datalen,
const unsigned char *pwd, size_t pwdlen,
const unsigned char *salt, size_t saltlen,
mbedtls_md_type_t md_type, int id, int iterations )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned int j;
unsigned char diversifier[128];
unsigned char salt_block[128], pwd_block[128], hash_block[128];
unsigned char hash_output[MBEDTLS_MD_MAX_SIZE];
unsigned char *p;
unsigned char c;
size_t hlen, use_len, v, i;
const mbedtls_md_info_t *md_info;
mbedtls_md_context_t md_ctx;
// This version only allows max of 64 bytes of password or salt
if( datalen > 128 || pwdlen > 64 || saltlen > 64 )
return( MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA );
md_info = mbedtls_md_info_from_type( md_type );
if( md_info == NULL )
return( MBEDTLS_ERR_PKCS12_FEATURE_UNAVAILABLE );
mbedtls_md_init( &md_ctx );
if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 0 ) ) != 0 )
return( ret );
hlen = mbedtls_md_get_size( md_info );
if( hlen <= 32 )
v = 64;
else
v = 128;
memset( diversifier, (unsigned char) id, v );
pkcs12_fill_buffer( salt_block, v, salt, saltlen );
pkcs12_fill_buffer( pwd_block, v, pwd, pwdlen );
p = data;
while( datalen > 0 )
{
// Calculate hash( diversifier || salt_block || pwd_block )
if( ( ret = mbedtls_md_starts( &md_ctx ) ) != 0 )
goto exit;
if( ( ret = mbedtls_md_update( &md_ctx, diversifier, v ) ) != 0 )
goto exit;
if( ( ret = mbedtls_md_update( &md_ctx, salt_block, v ) ) != 0 )
goto exit;
if( ( ret = mbedtls_md_update( &md_ctx, pwd_block, v ) ) != 0 )
goto exit;
if( ( ret = mbedtls_md_finish( &md_ctx, hash_output ) ) != 0 )
goto exit;
// Perform remaining ( iterations - 1 ) recursive hash calculations
for( i = 1; i < (size_t) iterations; i++ )
{
if( ( ret = mbedtls_md( md_info, hash_output, hlen, hash_output ) ) != 0 )
goto exit;
}
use_len = ( datalen > hlen ) ? hlen : datalen;
memcpy( p, hash_output, use_len );
datalen -= use_len;
p += use_len;
if( datalen == 0 )
break;
// Concatenating copies of hash_output into hash_block (B)
pkcs12_fill_buffer( hash_block, v, hash_output, hlen );
// B += 1
for( i = v; i > 0; i-- )
if( ++hash_block[i - 1] != 0 )
break;
// salt_block += B
c = 0;
for( i = v; i > 0; i-- )
{
j = salt_block[i - 1] + hash_block[i - 1] + c;
c = MBEDTLS_BYTE_1( j );
salt_block[i - 1] = MBEDTLS_BYTE_0( j );
}
// pwd_block += B
c = 0;
for( i = v; i > 0; i-- )
{
j = pwd_block[i - 1] + hash_block[i - 1] + c;
c = MBEDTLS_BYTE_1( j );
pwd_block[i - 1] = MBEDTLS_BYTE_0( j );
}
}
ret = 0;
exit:
mbedtls_platform_zeroize( salt_block, sizeof( salt_block ) );
mbedtls_platform_zeroize( pwd_block, sizeof( pwd_block ) );
mbedtls_platform_zeroize( hash_block, sizeof( hash_block ) );
mbedtls_platform_zeroize( hash_output, sizeof( hash_output ) );
mbedtls_md_free( &md_ctx );
return( ret );
}
#endif /* MBEDTLS_PKCS12_C */