500 lines
15 KiB
C
500 lines
15 KiB
C
/*
|
|
* PSA MAC layer on top of Mbed TLS software crypto
|
|
*/
|
|
/*
|
|
* 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.
|
|
*/
|
|
|
|
#include "common.h"
|
|
|
|
#if defined(MBEDTLS_PSA_CRYPTO_C)
|
|
|
|
#include <psa/crypto.h>
|
|
#include "psa_crypto_core.h"
|
|
#include "psa_crypto_mac.h"
|
|
#include <mbedtls/md.h>
|
|
|
|
#include <mbedtls/error.h>
|
|
#include <string.h>
|
|
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HMAC)
|
|
static psa_status_t psa_hmac_abort_internal(
|
|
mbedtls_psa_hmac_operation_t *hmac )
|
|
{
|
|
mbedtls_platform_zeroize( hmac->opad, sizeof( hmac->opad ) );
|
|
return( psa_hash_abort( &hmac->hash_ctx ) );
|
|
}
|
|
|
|
static psa_status_t psa_hmac_setup_internal(
|
|
mbedtls_psa_hmac_operation_t *hmac,
|
|
const uint8_t *key,
|
|
size_t key_length,
|
|
psa_algorithm_t hash_alg )
|
|
{
|
|
uint8_t ipad[PSA_HMAC_MAX_HASH_BLOCK_SIZE];
|
|
size_t i;
|
|
size_t hash_size = PSA_HASH_LENGTH( hash_alg );
|
|
size_t block_size = PSA_HASH_BLOCK_LENGTH( hash_alg );
|
|
psa_status_t status;
|
|
|
|
hmac->alg = hash_alg;
|
|
|
|
/* Sanity checks on block_size, to guarantee that there won't be a buffer
|
|
* overflow below. This should never trigger if the hash algorithm
|
|
* is implemented correctly. */
|
|
/* The size checks against the ipad and opad buffers cannot be written
|
|
* `block_size > sizeof( ipad ) || block_size > sizeof( hmac->opad )`
|
|
* because that triggers -Wlogical-op on GCC 7.3. */
|
|
if( block_size > sizeof( ipad ) )
|
|
return( PSA_ERROR_NOT_SUPPORTED );
|
|
if( block_size > sizeof( hmac->opad ) )
|
|
return( PSA_ERROR_NOT_SUPPORTED );
|
|
if( block_size < hash_size )
|
|
return( PSA_ERROR_NOT_SUPPORTED );
|
|
|
|
if( key_length > block_size )
|
|
{
|
|
status = psa_hash_compute( hash_alg, key, key_length,
|
|
ipad, sizeof( ipad ), &key_length );
|
|
if( status != PSA_SUCCESS )
|
|
goto cleanup;
|
|
}
|
|
/* A 0-length key is not commonly used in HMAC when used as a MAC,
|
|
* but it is permitted. It is common when HMAC is used in HKDF, for
|
|
* example. Don't call `memcpy` in the 0-length because `key` could be
|
|
* an invalid pointer which would make the behavior undefined. */
|
|
else if( key_length != 0 )
|
|
memcpy( ipad, key, key_length );
|
|
|
|
/* ipad contains the key followed by garbage. Xor and fill with 0x36
|
|
* to create the ipad value. */
|
|
for( i = 0; i < key_length; i++ )
|
|
ipad[i] ^= 0x36;
|
|
memset( ipad + key_length, 0x36, block_size - key_length );
|
|
|
|
/* Copy the key material from ipad to opad, flipping the requisite bits,
|
|
* and filling the rest of opad with the requisite constant. */
|
|
for( i = 0; i < key_length; i++ )
|
|
hmac->opad[i] = ipad[i] ^ 0x36 ^ 0x5C;
|
|
memset( hmac->opad + key_length, 0x5C, block_size - key_length );
|
|
|
|
status = psa_hash_setup( &hmac->hash_ctx, hash_alg );
|
|
if( status != PSA_SUCCESS )
|
|
goto cleanup;
|
|
|
|
status = psa_hash_update( &hmac->hash_ctx, ipad, block_size );
|
|
|
|
cleanup:
|
|
mbedtls_platform_zeroize( ipad, sizeof( ipad ) );
|
|
|
|
return( status );
|
|
}
|
|
|
|
static psa_status_t psa_hmac_update_internal(
|
|
mbedtls_psa_hmac_operation_t *hmac,
|
|
const uint8_t *data,
|
|
size_t data_length )
|
|
{
|
|
return( psa_hash_update( &hmac->hash_ctx, data, data_length ) );
|
|
}
|
|
|
|
static psa_status_t psa_hmac_finish_internal(
|
|
mbedtls_psa_hmac_operation_t *hmac,
|
|
uint8_t *mac,
|
|
size_t mac_size )
|
|
{
|
|
uint8_t tmp[PSA_HASH_MAX_SIZE];
|
|
psa_algorithm_t hash_alg = hmac->alg;
|
|
size_t hash_size = 0;
|
|
size_t block_size = PSA_HASH_BLOCK_LENGTH( hash_alg );
|
|
psa_status_t status;
|
|
|
|
status = psa_hash_finish( &hmac->hash_ctx, tmp, sizeof( tmp ), &hash_size );
|
|
if( status != PSA_SUCCESS )
|
|
return( status );
|
|
/* From here on, tmp needs to be wiped. */
|
|
|
|
status = psa_hash_setup( &hmac->hash_ctx, hash_alg );
|
|
if( status != PSA_SUCCESS )
|
|
goto exit;
|
|
|
|
status = psa_hash_update( &hmac->hash_ctx, hmac->opad, block_size );
|
|
if( status != PSA_SUCCESS )
|
|
goto exit;
|
|
|
|
status = psa_hash_update( &hmac->hash_ctx, tmp, hash_size );
|
|
if( status != PSA_SUCCESS )
|
|
goto exit;
|
|
|
|
status = psa_hash_finish( &hmac->hash_ctx, tmp, sizeof( tmp ), &hash_size );
|
|
if( status != PSA_SUCCESS )
|
|
goto exit;
|
|
|
|
memcpy( mac, tmp, mac_size );
|
|
|
|
exit:
|
|
mbedtls_platform_zeroize( tmp, hash_size );
|
|
return( status );
|
|
}
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HMAC */
|
|
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CMAC)
|
|
static psa_status_t cmac_setup( mbedtls_psa_mac_operation_t *operation,
|
|
const psa_key_attributes_t *attributes,
|
|
const uint8_t *key_buffer )
|
|
{
|
|
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
|
|
|
|
#if defined(PSA_WANT_KEY_TYPE_DES)
|
|
/* Mbed TLS CMAC does not accept 3DES with only two keys, nor does it accept
|
|
* to do CMAC with pure DES, so return NOT_SUPPORTED here. */
|
|
if( psa_get_key_type( attributes ) == PSA_KEY_TYPE_DES &&
|
|
( psa_get_key_bits( attributes ) == 64 ||
|
|
psa_get_key_bits( attributes ) == 128 ) )
|
|
return( PSA_ERROR_NOT_SUPPORTED );
|
|
#endif
|
|
|
|
const mbedtls_cipher_info_t * cipher_info =
|
|
mbedtls_cipher_info_from_psa(
|
|
PSA_ALG_CMAC,
|
|
psa_get_key_type( attributes ),
|
|
psa_get_key_bits( attributes ),
|
|
NULL );
|
|
|
|
if( cipher_info == NULL )
|
|
return( PSA_ERROR_NOT_SUPPORTED );
|
|
|
|
ret = mbedtls_cipher_setup( &operation->ctx.cmac, cipher_info );
|
|
if( ret != 0 )
|
|
goto exit;
|
|
|
|
ret = mbedtls_cipher_cmac_starts( &operation->ctx.cmac,
|
|
key_buffer,
|
|
psa_get_key_bits( attributes ) );
|
|
exit:
|
|
return( mbedtls_to_psa_error( ret ) );
|
|
}
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CMAC */
|
|
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HMAC) || \
|
|
defined(MBEDTLS_PSA_BUILTIN_ALG_CMAC)
|
|
|
|
/* Initialize this driver's MAC operation structure. Once this function has been
|
|
* called, mbedtls_psa_mac_abort can run and will do the right thing. */
|
|
static psa_status_t mac_init(
|
|
mbedtls_psa_mac_operation_t *operation,
|
|
psa_algorithm_t alg )
|
|
{
|
|
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
|
|
|
|
operation->alg = alg;
|
|
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CMAC)
|
|
if( PSA_ALG_FULL_LENGTH_MAC( operation->alg ) == PSA_ALG_CMAC )
|
|
{
|
|
mbedtls_cipher_init( &operation->ctx.cmac );
|
|
status = PSA_SUCCESS;
|
|
}
|
|
else
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CMAC */
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HMAC)
|
|
if( PSA_ALG_IS_HMAC( operation->alg ) )
|
|
{
|
|
/* We'll set up the hash operation later in psa_hmac_setup_internal. */
|
|
operation->ctx.hmac.alg = 0;
|
|
status = PSA_SUCCESS;
|
|
}
|
|
else
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HMAC */
|
|
{
|
|
(void) operation;
|
|
status = PSA_ERROR_NOT_SUPPORTED;
|
|
}
|
|
|
|
if( status != PSA_SUCCESS )
|
|
memset( operation, 0, sizeof( *operation ) );
|
|
return( status );
|
|
}
|
|
|
|
psa_status_t mbedtls_psa_mac_abort( mbedtls_psa_mac_operation_t *operation )
|
|
{
|
|
if( operation->alg == 0 )
|
|
{
|
|
/* The object has (apparently) been initialized but it is not
|
|
* in use. It's ok to call abort on such an object, and there's
|
|
* nothing to do. */
|
|
return( PSA_SUCCESS );
|
|
}
|
|
else
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CMAC)
|
|
if( PSA_ALG_FULL_LENGTH_MAC( operation->alg ) == PSA_ALG_CMAC )
|
|
{
|
|
mbedtls_cipher_free( &operation->ctx.cmac );
|
|
}
|
|
else
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CMAC */
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HMAC)
|
|
if( PSA_ALG_IS_HMAC( operation->alg ) )
|
|
{
|
|
psa_hmac_abort_internal( &operation->ctx.hmac );
|
|
}
|
|
else
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HMAC */
|
|
{
|
|
/* Sanity check (shouldn't happen: operation->alg should
|
|
* always have been initialized to a valid value). */
|
|
goto bad_state;
|
|
}
|
|
|
|
operation->alg = 0;
|
|
|
|
return( PSA_SUCCESS );
|
|
|
|
bad_state:
|
|
/* If abort is called on an uninitialized object, we can't trust
|
|
* anything. Wipe the object in case it contains confidential data.
|
|
* This may result in a memory leak if a pointer gets overwritten,
|
|
* but it's too late to do anything about this. */
|
|
memset( operation, 0, sizeof( *operation ) );
|
|
return( PSA_ERROR_BAD_STATE );
|
|
}
|
|
|
|
static psa_status_t psa_mac_setup( mbedtls_psa_mac_operation_t *operation,
|
|
const psa_key_attributes_t *attributes,
|
|
const uint8_t *key_buffer,
|
|
size_t key_buffer_size,
|
|
psa_algorithm_t alg )
|
|
{
|
|
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
|
|
|
|
/* A context must be freshly initialized before it can be set up. */
|
|
if( operation->alg != 0 )
|
|
return( PSA_ERROR_BAD_STATE );
|
|
|
|
status = mac_init( operation, alg );
|
|
if( status != PSA_SUCCESS )
|
|
return( status );
|
|
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CMAC)
|
|
if( PSA_ALG_FULL_LENGTH_MAC( alg ) == PSA_ALG_CMAC )
|
|
{
|
|
/* Key buffer size for CMAC is dictated by the key bits set on the
|
|
* attributes, and previously validated by the core on key import. */
|
|
(void) key_buffer_size;
|
|
status = cmac_setup( operation, attributes, key_buffer );
|
|
}
|
|
else
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CMAC */
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HMAC)
|
|
if( PSA_ALG_IS_HMAC( alg ) )
|
|
{
|
|
status = psa_hmac_setup_internal( &operation->ctx.hmac,
|
|
key_buffer,
|
|
key_buffer_size,
|
|
PSA_ALG_HMAC_GET_HASH( alg ) );
|
|
}
|
|
else
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HMAC */
|
|
{
|
|
(void) attributes;
|
|
(void) key_buffer;
|
|
(void) key_buffer_size;
|
|
status = PSA_ERROR_NOT_SUPPORTED;
|
|
}
|
|
|
|
if( status != PSA_SUCCESS )
|
|
mbedtls_psa_mac_abort( operation );
|
|
|
|
return( status );
|
|
}
|
|
|
|
psa_status_t mbedtls_psa_mac_sign_setup(
|
|
mbedtls_psa_mac_operation_t *operation,
|
|
const psa_key_attributes_t *attributes,
|
|
const uint8_t *key_buffer,
|
|
size_t key_buffer_size,
|
|
psa_algorithm_t alg )
|
|
{
|
|
return( psa_mac_setup( operation, attributes,
|
|
key_buffer, key_buffer_size, alg ) );
|
|
}
|
|
|
|
psa_status_t mbedtls_psa_mac_verify_setup(
|
|
mbedtls_psa_mac_operation_t *operation,
|
|
const psa_key_attributes_t *attributes,
|
|
const uint8_t *key_buffer,
|
|
size_t key_buffer_size,
|
|
psa_algorithm_t alg )
|
|
{
|
|
return( psa_mac_setup( operation, attributes,
|
|
key_buffer, key_buffer_size, alg ) );
|
|
}
|
|
|
|
psa_status_t mbedtls_psa_mac_update(
|
|
mbedtls_psa_mac_operation_t *operation,
|
|
const uint8_t *input,
|
|
size_t input_length )
|
|
{
|
|
if( operation->alg == 0 )
|
|
return( PSA_ERROR_BAD_STATE );
|
|
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CMAC)
|
|
if( PSA_ALG_FULL_LENGTH_MAC( operation->alg ) == PSA_ALG_CMAC )
|
|
{
|
|
return( mbedtls_to_psa_error(
|
|
mbedtls_cipher_cmac_update( &operation->ctx.cmac,
|
|
input, input_length ) ) );
|
|
}
|
|
else
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CMAC */
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HMAC)
|
|
if( PSA_ALG_IS_HMAC( operation->alg ) )
|
|
{
|
|
return( psa_hmac_update_internal( &operation->ctx.hmac,
|
|
input, input_length ) );
|
|
}
|
|
else
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HMAC */
|
|
{
|
|
/* This shouldn't happen if `operation` was initialized by
|
|
* a setup function. */
|
|
(void) input;
|
|
(void) input_length;
|
|
return( PSA_ERROR_BAD_STATE );
|
|
}
|
|
}
|
|
|
|
static psa_status_t psa_mac_finish_internal(
|
|
mbedtls_psa_mac_operation_t *operation,
|
|
uint8_t *mac, size_t mac_size )
|
|
{
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CMAC)
|
|
if( PSA_ALG_FULL_LENGTH_MAC( operation->alg ) == PSA_ALG_CMAC )
|
|
{
|
|
uint8_t tmp[PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE];
|
|
int ret = mbedtls_cipher_cmac_finish( &operation->ctx.cmac, tmp );
|
|
if( ret == 0 )
|
|
memcpy( mac, tmp, mac_size );
|
|
mbedtls_platform_zeroize( tmp, sizeof( tmp ) );
|
|
return( mbedtls_to_psa_error( ret ) );
|
|
}
|
|
else
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CMAC */
|
|
#if defined(MBEDTLS_PSA_BUILTIN_ALG_HMAC)
|
|
if( PSA_ALG_IS_HMAC( operation->alg ) )
|
|
{
|
|
return( psa_hmac_finish_internal( &operation->ctx.hmac,
|
|
mac, mac_size ) );
|
|
}
|
|
else
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HMAC */
|
|
{
|
|
/* This shouldn't happen if `operation` was initialized by
|
|
* a setup function. */
|
|
(void) operation;
|
|
(void) mac;
|
|
(void) mac_size;
|
|
return( PSA_ERROR_BAD_STATE );
|
|
}
|
|
}
|
|
|
|
psa_status_t mbedtls_psa_mac_sign_finish(
|
|
mbedtls_psa_mac_operation_t *operation,
|
|
uint8_t *mac,
|
|
size_t mac_size,
|
|
size_t *mac_length )
|
|
{
|
|
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
|
|
|
|
if( operation->alg == 0 )
|
|
return( PSA_ERROR_BAD_STATE );
|
|
|
|
status = psa_mac_finish_internal( operation, mac, mac_size );
|
|
if( status == PSA_SUCCESS )
|
|
*mac_length = mac_size;
|
|
|
|
return( status );
|
|
}
|
|
|
|
psa_status_t mbedtls_psa_mac_verify_finish(
|
|
mbedtls_psa_mac_operation_t *operation,
|
|
const uint8_t *mac,
|
|
size_t mac_length )
|
|
{
|
|
uint8_t actual_mac[PSA_MAC_MAX_SIZE];
|
|
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
|
|
|
|
if( operation->alg == 0 )
|
|
return( PSA_ERROR_BAD_STATE );
|
|
|
|
/* Consistency check: requested MAC length fits our local buffer */
|
|
if( mac_length > sizeof( actual_mac ) )
|
|
return( PSA_ERROR_INVALID_ARGUMENT );
|
|
|
|
status = psa_mac_finish_internal( operation, actual_mac, mac_length );
|
|
if( status != PSA_SUCCESS )
|
|
goto cleanup;
|
|
|
|
if( mbedtls_psa_safer_memcmp( mac, actual_mac, mac_length ) != 0 )
|
|
status = PSA_ERROR_INVALID_SIGNATURE;
|
|
|
|
cleanup:
|
|
mbedtls_platform_zeroize( actual_mac, sizeof( actual_mac ) );
|
|
|
|
return( status );
|
|
}
|
|
|
|
psa_status_t mbedtls_psa_mac_compute(
|
|
const psa_key_attributes_t *attributes,
|
|
const uint8_t *key_buffer,
|
|
size_t key_buffer_size,
|
|
psa_algorithm_t alg,
|
|
const uint8_t *input,
|
|
size_t input_length,
|
|
uint8_t *mac,
|
|
size_t mac_size,
|
|
size_t *mac_length )
|
|
{
|
|
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
|
|
mbedtls_psa_mac_operation_t operation = MBEDTLS_PSA_MAC_OPERATION_INIT;
|
|
|
|
status = psa_mac_setup( &operation,
|
|
attributes, key_buffer, key_buffer_size,
|
|
alg );
|
|
if( status != PSA_SUCCESS )
|
|
goto exit;
|
|
|
|
if( input_length > 0 )
|
|
{
|
|
status = mbedtls_psa_mac_update( &operation, input, input_length );
|
|
if( status != PSA_SUCCESS )
|
|
goto exit;
|
|
}
|
|
|
|
status = psa_mac_finish_internal( &operation, mac, mac_size );
|
|
if( status == PSA_SUCCESS )
|
|
*mac_length = mac_size;
|
|
|
|
exit:
|
|
mbedtls_psa_mac_abort( &operation );
|
|
|
|
return( status );
|
|
}
|
|
|
|
#endif /* MBEDTLS_PSA_BUILTIN_ALG_HMAC || MBEDTLS_PSA_BUILTIN_ALG_CMAC */
|
|
|
|
#endif /* MBEDTLS_PSA_CRYPTO_C */
|