mirror of https://github.com/ARMmbed/mbed-os.git
140 lines
4.3 KiB
C
140 lines
4.3 KiB
C
/*
|
|
* ccm_alt.c
|
|
*
|
|
* Copyright (C) 2018, 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.
|
|
*
|
|
*/
|
|
|
|
#include "mbedtls/ccm.h"
|
|
#if defined(MBEDTLS_CCM_ALT)
|
|
#include <string.h>
|
|
#include "mbedtls/platform.h"
|
|
#include "mbedtls/aes.h"
|
|
|
|
/* Implementation that should never be optimized out by the compiler */
|
|
static void mbedtls_zeroize( void *v, size_t n ) {
|
|
volatile unsigned char *p = (unsigned char*)v;
|
|
while( n-- ) *p++ = 0;
|
|
}
|
|
|
|
void mbedtls_ccm_init( mbedtls_ccm_context *ctx )
|
|
{
|
|
memset( ctx, 0, sizeof( mbedtls_ccm_context ) );
|
|
}
|
|
|
|
void mbedtls_ccm_free( mbedtls_ccm_context *ctx )
|
|
{
|
|
mbedtls_zeroize( ctx, sizeof( mbedtls_ccm_context ) );
|
|
}
|
|
|
|
int mbedtls_ccm_setkey( mbedtls_ccm_context *ctx,
|
|
mbedtls_cipher_id_t cipher,
|
|
const unsigned char *key,
|
|
unsigned int keybits )
|
|
{
|
|
if( ctx == NULL )
|
|
return ( MBEDTLS_ERR_CCM_BAD_INPUT );
|
|
|
|
if( cipher != MBEDTLS_CIPHER_ID_AES ||
|
|
keybits != 128 )
|
|
{
|
|
return ( MBEDTLS_ERR_AES_FEATURE_UNAVAILABLE );
|
|
}
|
|
|
|
memcpy( ctx->cipher_key , key, keybits / 8 );
|
|
ctx->keySize_ID = CRYS_AES_Key128BitSize;
|
|
|
|
return ( 0 );
|
|
|
|
}
|
|
|
|
/*
|
|
* Authenticated encryption or decryption
|
|
*/
|
|
|
|
int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
|
|
const unsigned char *iv, size_t iv_len,
|
|
const unsigned char *add, size_t add_len,
|
|
const unsigned char *input, unsigned char *output,
|
|
unsigned char *tag, size_t tag_len )
|
|
|
|
{
|
|
CRYSError_t CrysRet = CRYS_OK;
|
|
/*
|
|
* Check length requirements: SP800-38C A.1
|
|
* Additional requirement: a < 2^16 - 2^8 to simplify the code.
|
|
* 'length' checked later (when writing it to the first block)
|
|
*/
|
|
if( tag_len < 4 || tag_len > 16 || tag_len % 2 != 0 )
|
|
return ( MBEDTLS_ERR_CCM_BAD_INPUT );
|
|
|
|
/* Also implies q is within bounds */
|
|
if( iv_len < 7 || iv_len > 13 )
|
|
return ( MBEDTLS_ERR_CCM_BAD_INPUT );
|
|
|
|
#if SIZE_MAX > UINT_MAX
|
|
if( length > 0xFFFFFFFF || add_len > 0xFFFFFFFF )
|
|
return ( MBEDTLS_ERR_CCM_BAD_INPUT );
|
|
#endif
|
|
|
|
CrysRet = CRYS_AESCCM( SASI_AES_ENCRYPT, ctx->cipher_key, ctx->keySize_ID,(uint8_t*)iv, iv_len,
|
|
(uint8_t*)add, add_len, (uint8_t*)input, length, output, tag_len, tag );
|
|
if( CrysRet != CRYS_OK )
|
|
return ( MBEDTLS_ERR_CCM_HW_ACCEL_FAILED );
|
|
|
|
return ( 0 );
|
|
|
|
}
|
|
|
|
/*
|
|
* Authenticated decryption
|
|
*/
|
|
int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
|
|
const unsigned char *iv, size_t iv_len,
|
|
const unsigned char *add, size_t add_len,
|
|
const unsigned char *input, unsigned char *output,
|
|
const unsigned char *tag, size_t tag_len )
|
|
|
|
{
|
|
CRYSError_t CrysRet = CRYS_OK;
|
|
/*
|
|
* Check length requirements: SP800-38C A.1
|
|
* Additional requirement: a < 2^16 - 2^8 to simplify the code.
|
|
* 'length' checked later (when writing it to the first block)
|
|
*/
|
|
if( tag_len < 4 || tag_len > 16 || tag_len % 2 != 0 )
|
|
return ( MBEDTLS_ERR_CCM_BAD_INPUT );
|
|
|
|
/* Also implies q is within bounds */
|
|
if( iv_len < 7 || iv_len > 13 )
|
|
return ( MBEDTLS_ERR_CCM_BAD_INPUT );
|
|
|
|
#if SIZE_MAX > UINT_MAX
|
|
if( length > 0xFFFFFFFF || add_len > 0xFFFFFFFF )
|
|
return ( MBEDTLS_ERR_CCM_BAD_INPUT );
|
|
#endif
|
|
|
|
CrysRet = CRYS_AESCCM( SASI_AES_DECRYPT, ctx->cipher_key, ctx->keySize_ID,(uint8_t*)iv, iv_len,
|
|
(uint8_t*)add, add_len, (uint8_t*)input, length, output, tag_len, (uint8_t*)tag );
|
|
if ( CrysRet != CRYS_OK )
|
|
return ( MBEDTLS_ERR_CCM_HW_ACCEL_FAILED );
|
|
|
|
return ( 0 );
|
|
|
|
}
|
|
|
|
#endif
|