mbedtls/library/pkcs5.c
Antonio Quartulli 12ccef2761
pkcs5v2: add support for additional hmacSHA algorithms
Currently only SHA1 is supported as PRF algorithm for PBKDF2
(PKCS#5 v2.0).
This means that keys encrypted and authenticated using
another algorithm of the SHA family cannot be decrypted.

This deficiency has become particularly incumbent now that
PKIs created with OpenSSL1.1 are encrypting keys using
hmacSHA256 by default (OpenSSL1.0 used PKCS#5 v1.0 by default
and even if v2 was forced, it would still use hmacSHA1).

Enable support for all the digest algorithms of the SHA
family for PKCS#5 v2.0.

Signed-off-by: Antonio Quartulli <antonio@openvpn.net>
2018-02-08 17:18:15 +08:00

405 lines
11 KiB
C

/**
* \file pkcs5.c
*
* \brief PKCS#5 functions
*
* \author Mathias Olsson <mathias@kompetensum.com>
*
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
* 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.
*
* This file is part of mbed TLS (https://tls.mbed.org)
*/
/*
* PKCS#5 includes PBKDF2 and more
*
* http://tools.ietf.org/html/rfc2898 (Specification)
* http://tools.ietf.org/html/rfc6070 (Test vectors)
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_PKCS5_C)
#include "mbedtls/pkcs5.h"
#include "mbedtls/asn1.h"
#include "mbedtls/cipher.h"
#include "mbedtls/oid.h"
#include <string.h>
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdio.h>
#define mbedtls_printf printf
#endif
static int pkcs5_parse_pbkdf2_params( const mbedtls_asn1_buf *params,
mbedtls_asn1_buf *salt, int *iterations,
int *keylen, mbedtls_md_type_t *md_type )
{
int ret;
mbedtls_asn1_buf prf_alg_oid;
unsigned char *p = params->p;
const unsigned char *end = params->p + params->len;
if( params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT +
MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
/*
* PBKDF2-params ::= SEQUENCE {
* salt OCTET STRING,
* iterationCount INTEGER,
* keyLength INTEGER OPTIONAL
* prf AlgorithmIdentifier DEFAULT algid-hmacWithSHA1
* }
*
*/
if( ( ret = mbedtls_asn1_get_tag( &p, end, &salt->len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret );
salt->p = p;
p += salt->len;
if( ( ret = mbedtls_asn1_get_int( &p, end, iterations ) ) != 0 )
return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret );
if( p == end )
return( 0 );
if( ( ret = mbedtls_asn1_get_int( &p, end, keylen ) ) != 0 )
{
if( ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG )
return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret );
}
if( p == end )
return( 0 );
if( ( ret = mbedtls_asn1_get_alg_null( &p, end, &prf_alg_oid ) ) != 0 )
return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret );
if( mbedtls_oid_get_md_hmac( &prf_alg_oid, md_type ) != 0 )
return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
if( p != end )
return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT +
MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
return( 0 );
}
int mbedtls_pkcs5_pbes2( const mbedtls_asn1_buf *pbe_params, int mode,
const unsigned char *pwd, size_t pwdlen,
const unsigned char *data, size_t datalen,
unsigned char *output )
{
int ret, iterations = 0, keylen = 0;
unsigned char *p, *end;
mbedtls_asn1_buf kdf_alg_oid, enc_scheme_oid, kdf_alg_params, enc_scheme_params;
mbedtls_asn1_buf salt;
mbedtls_md_type_t md_type = MBEDTLS_MD_SHA1;
unsigned char key[32], iv[32];
size_t olen = 0;
const mbedtls_md_info_t *md_info;
const mbedtls_cipher_info_t *cipher_info;
mbedtls_md_context_t md_ctx;
mbedtls_cipher_type_t cipher_alg;
mbedtls_cipher_context_t cipher_ctx;
p = pbe_params->p;
end = p + pbe_params->len;
/*
* PBES2-params ::= SEQUENCE {
* keyDerivationFunc AlgorithmIdentifier {{PBES2-KDFs}},
* encryptionScheme AlgorithmIdentifier {{PBES2-Encs}}
* }
*/
if( pbe_params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT +
MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
if( ( ret = mbedtls_asn1_get_alg( &p, end, &kdf_alg_oid, &kdf_alg_params ) ) != 0 )
return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret );
// Only PBKDF2 supported at the moment
//
if( MBEDTLS_OID_CMP( MBEDTLS_OID_PKCS5_PBKDF2, &kdf_alg_oid ) != 0 )
return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
if( ( ret = pkcs5_parse_pbkdf2_params( &kdf_alg_params,
&salt, &iterations, &keylen,
&md_type ) ) != 0 )
{
return( ret );
}
md_info = mbedtls_md_info_from_type( md_type );
if( md_info == NULL )
return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
if( ( ret = mbedtls_asn1_get_alg( &p, end, &enc_scheme_oid,
&enc_scheme_params ) ) != 0 )
{
return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT + ret );
}
if( mbedtls_oid_get_cipher_alg( &enc_scheme_oid, &cipher_alg ) != 0 )
return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
cipher_info = mbedtls_cipher_info_from_type( cipher_alg );
if( cipher_info == NULL )
return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );
/*
* The value of keylen from pkcs5_parse_pbkdf2_params() is ignored
* since it is optional and we don't know if it was set or not
*/
keylen = cipher_info->key_bitlen / 8;
if( enc_scheme_params.tag != MBEDTLS_ASN1_OCTET_STRING ||
enc_scheme_params.len != cipher_info->iv_size )
{
return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT );
}
mbedtls_md_init( &md_ctx );
mbedtls_cipher_init( &cipher_ctx );
memcpy( iv, enc_scheme_params.p, enc_scheme_params.len );
if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 1 ) ) != 0 )
goto exit;
if( ( ret = mbedtls_pkcs5_pbkdf2_hmac( &md_ctx, pwd, pwdlen, salt.p, salt.len,
iterations, keylen, key ) ) != 0 )
{
goto exit;
}
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_crypt( &cipher_ctx, iv, enc_scheme_params.len,
data, datalen, output, &olen ) ) != 0 )
ret = MBEDTLS_ERR_PKCS5_PASSWORD_MISMATCH;
exit:
mbedtls_md_free( &md_ctx );
mbedtls_cipher_free( &cipher_ctx );
return( ret );
}
int mbedtls_pkcs5_pbkdf2_hmac( mbedtls_md_context_t *ctx, const unsigned char *password,
size_t plen, const unsigned char *salt, size_t slen,
unsigned int iteration_count,
uint32_t key_length, unsigned char *output )
{
int ret, j;
unsigned int i;
unsigned char md1[MBEDTLS_MD_MAX_SIZE];
unsigned char work[MBEDTLS_MD_MAX_SIZE];
unsigned char md_size = mbedtls_md_get_size( ctx->md_info );
size_t use_len;
unsigned char *out_p = output;
unsigned char counter[4];
memset( counter, 0, 4 );
counter[3] = 1;
if( iteration_count > 0xFFFFFFFF )
return( MBEDTLS_ERR_PKCS5_BAD_INPUT_DATA );
while( key_length )
{
// U1 ends up in work
//
if( ( ret = mbedtls_md_hmac_starts( ctx, password, plen ) ) != 0 )
return( ret );
if( ( ret = mbedtls_md_hmac_update( ctx, salt, slen ) ) != 0 )
return( ret );
if( ( ret = mbedtls_md_hmac_update( ctx, counter, 4 ) ) != 0 )
return( ret );
if( ( ret = mbedtls_md_hmac_finish( ctx, work ) ) != 0 )
return( ret );
memcpy( md1, work, md_size );
for( i = 1; i < iteration_count; i++ )
{
// U2 ends up in md1
//
if( ( ret = mbedtls_md_hmac_starts( ctx, password, plen ) ) != 0 )
return( ret );
if( ( ret = mbedtls_md_hmac_update( ctx, md1, md_size ) ) != 0 )
return( ret );
if( ( ret = mbedtls_md_hmac_finish( ctx, md1 ) ) != 0 )
return( ret );
// U1 xor U2
//
for( j = 0; j < md_size; j++ )
work[j] ^= md1[j];
}
use_len = ( key_length < md_size ) ? key_length : md_size;
memcpy( out_p, work, use_len );
key_length -= (uint32_t) use_len;
out_p += use_len;
for( i = 4; i > 0; i-- )
if( ++counter[i - 1] != 0 )
break;
}
return( 0 );
}
#if defined(MBEDTLS_SELF_TEST)
#if !defined(MBEDTLS_SHA1_C)
int mbedtls_pkcs5_self_test( int verbose )
{
if( verbose != 0 )
mbedtls_printf( " PBKDF2 (SHA1): skipped\n\n" );
return( 0 );
}
#else
#define MAX_TESTS 6
static const size_t plen[MAX_TESTS] =
{ 8, 8, 8, 24, 9 };
static const unsigned char password[MAX_TESTS][32] =
{
"password",
"password",
"password",
"passwordPASSWORDpassword",
"pass\0word",
};
static const size_t slen[MAX_TESTS] =
{ 4, 4, 4, 36, 5 };
static const unsigned char salt[MAX_TESTS][40] =
{
"salt",
"salt",
"salt",
"saltSALTsaltSALTsaltSALTsaltSALTsalt",
"sa\0lt",
};
static const uint32_t it_cnt[MAX_TESTS] =
{ 1, 2, 4096, 4096, 4096 };
static const uint32_t key_len[MAX_TESTS] =
{ 20, 20, 20, 25, 16 };
static const unsigned char result_key[MAX_TESTS][32] =
{
{ 0x0c, 0x60, 0xc8, 0x0f, 0x96, 0x1f, 0x0e, 0x71,
0xf3, 0xa9, 0xb5, 0x24, 0xaf, 0x60, 0x12, 0x06,
0x2f, 0xe0, 0x37, 0xa6 },
{ 0xea, 0x6c, 0x01, 0x4d, 0xc7, 0x2d, 0x6f, 0x8c,
0xcd, 0x1e, 0xd9, 0x2a, 0xce, 0x1d, 0x41, 0xf0,
0xd8, 0xde, 0x89, 0x57 },
{ 0x4b, 0x00, 0x79, 0x01, 0xb7, 0x65, 0x48, 0x9a,
0xbe, 0xad, 0x49, 0xd9, 0x26, 0xf7, 0x21, 0xd0,
0x65, 0xa4, 0x29, 0xc1 },
{ 0x3d, 0x2e, 0xec, 0x4f, 0xe4, 0x1c, 0x84, 0x9b,
0x80, 0xc8, 0xd8, 0x36, 0x62, 0xc0, 0xe4, 0x4a,
0x8b, 0x29, 0x1a, 0x96, 0x4c, 0xf2, 0xf0, 0x70,
0x38 },
{ 0x56, 0xfa, 0x6a, 0xa7, 0x55, 0x48, 0x09, 0x9d,
0xcc, 0x37, 0xd7, 0xf0, 0x34, 0x25, 0xe0, 0xc3 },
};
int mbedtls_pkcs5_self_test( int verbose )
{
mbedtls_md_context_t sha1_ctx;
const mbedtls_md_info_t *info_sha1;
int ret, i;
unsigned char key[64];
mbedtls_md_init( &sha1_ctx );
info_sha1 = mbedtls_md_info_from_type( MBEDTLS_MD_SHA1 );
if( info_sha1 == NULL )
{
ret = 1;
goto exit;
}
if( ( ret = mbedtls_md_setup( &sha1_ctx, info_sha1, 1 ) ) != 0 )
{
ret = 1;
goto exit;
}
for( i = 0; i < MAX_TESTS; i++ )
{
if( verbose != 0 )
mbedtls_printf( " PBKDF2 (SHA1) #%d: ", i );
ret = mbedtls_pkcs5_pbkdf2_hmac( &sha1_ctx, password[i], plen[i], salt[i],
slen[i], it_cnt[i], key_len[i], key );
if( ret != 0 ||
memcmp( result_key[i], key, key_len[i] ) != 0 )
{
if( verbose != 0 )
mbedtls_printf( "failed\n" );
ret = 1;
goto exit;
}
if( verbose != 0 )
mbedtls_printf( "passed\n" );
}
if( verbose != 0 )
mbedtls_printf( "\n" );
exit:
mbedtls_md_free( &sha1_ctx );
return( ret );
}
#endif /* MBEDTLS_SHA1_C */
#endif /* MBEDTLS_SELF_TEST */
#endif /* MBEDTLS_PKCS5_C */