mbedtls/library/psa_crypto_cipher.c
Ronald Cron 937dfee92c psa: cipher: Re-organize multi-part operation context
Move members that are of no use to the PSA crypto core
to the Mbed TLS implementation specific operation context.

Signed-off-by: Ronald Cron <ronald.cron@arm.com>
2021-03-26 11:38:40 +01:00

373 lines
12 KiB
C

/*
* PSA cipher driver entry points
*/
/*
* 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_cipher.h>
#include "psa_crypto_core.h"
#include "psa_crypto_random_impl.h"
#include "mbedtls/cipher.h"
#include "mbedtls/error.h"
#include <string.h>
static psa_status_t cipher_setup(
psa_cipher_operation_t *operation,
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg,
mbedtls_operation_t cipher_operation )
{
int ret = 0;
size_t key_bits;
const mbedtls_cipher_info_t *cipher_info = NULL;
psa_key_type_t key_type = attributes->core.type;
mbedtls_psa_cipher_operation_t *mbedtls_ctx = &operation->ctx.mbedtls_ctx;
(void)key_buffer_size;
/* Proceed with initializing an mbed TLS cipher context if no driver is
* available for the given algorithm & key. */
mbedtls_cipher_init( &mbedtls_ctx->cipher );
mbedtls_ctx->alg = alg;
key_bits = attributes->core.bits;
cipher_info = mbedtls_cipher_info_from_psa( alg, key_type,
key_bits, NULL );
if( cipher_info == NULL )
return( PSA_ERROR_NOT_SUPPORTED );
ret = mbedtls_cipher_setup( &mbedtls_ctx->cipher, cipher_info );
if( ret != 0 )
goto exit;
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DES)
if( key_type == PSA_KEY_TYPE_DES && key_bits == 128 )
{
/* Two-key Triple-DES is 3-key Triple-DES with K1=K3 */
uint8_t keys[24];
memcpy( keys, key_buffer, 16 );
memcpy( keys + 16, key_buffer, 8 );
ret = mbedtls_cipher_setkey( &mbedtls_ctx->cipher,
keys,
192, cipher_operation );
}
else
#endif
{
ret = mbedtls_cipher_setkey( &mbedtls_ctx->cipher, key_buffer,
(int) key_bits, cipher_operation );
}
if( ret != 0 )
goto exit;
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CBC_NO_PADDING) || \
defined(MBEDTLS_PSA_BUILTIN_ALG_CBC_PKCS7)
switch( alg )
{
case PSA_ALG_CBC_NO_PADDING:
ret = mbedtls_cipher_set_padding_mode( &mbedtls_ctx->cipher,
MBEDTLS_PADDING_NONE );
break;
case PSA_ALG_CBC_PKCS7:
ret = mbedtls_cipher_set_padding_mode( &mbedtls_ctx->cipher,
MBEDTLS_PADDING_PKCS7 );
break;
default:
/* The algorithm doesn't involve padding. */
ret = 0;
break;
}
if( ret != 0 )
goto exit;
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CBC_NO_PADDING || MBEDTLS_PSA_BUILTIN_ALG_CBC_PKCS7 */
mbedtls_ctx->block_size = ( PSA_ALG_IS_STREAM_CIPHER( alg ) ? 1 :
PSA_BLOCK_CIPHER_BLOCK_LENGTH( key_type ) );
if( ( alg & PSA_ALG_CIPHER_FROM_BLOCK_FLAG ) != 0 &&
alg != PSA_ALG_ECB_NO_PADDING )
{
mbedtls_ctx->iv_size = PSA_BLOCK_CIPHER_BLOCK_LENGTH( key_type );
}
#if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_CHACHA20)
else
if( ( alg == PSA_ALG_STREAM_CIPHER ) &&
( key_type == PSA_KEY_TYPE_CHACHA20 ) )
mbedtls_ctx->iv_size = 12;
#endif
exit:
return( mbedtls_to_psa_error( ret ) );
}
psa_status_t mbedtls_psa_cipher_encrypt_setup(
psa_cipher_operation_t *operation,
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg )
{
return( cipher_setup( operation, attributes,
key_buffer, key_buffer_size,
alg, MBEDTLS_ENCRYPT ) );
}
psa_status_t mbedtls_psa_cipher_decrypt_setup(
psa_cipher_operation_t *operation,
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg )
{
return( cipher_setup( operation, attributes,
key_buffer, key_buffer_size,
alg, MBEDTLS_DECRYPT ) );
}
psa_status_t mbedtls_psa_cipher_generate_iv(
psa_cipher_operation_t *operation,
uint8_t *iv, size_t iv_size, size_t *iv_length )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
mbedtls_psa_cipher_operation_t *mbedtls_ctx = &operation->ctx.mbedtls_ctx;
if( iv_size < mbedtls_ctx->iv_size )
return( PSA_ERROR_BUFFER_TOO_SMALL );
ret = mbedtls_psa_get_random( MBEDTLS_PSA_RANDOM_STATE,
iv, mbedtls_ctx->iv_size );
if( ret != 0 )
return( mbedtls_to_psa_error( ret ) );
*iv_length = mbedtls_ctx->iv_size;
return( mbedtls_psa_cipher_set_iv( operation, iv, *iv_length ) );
}
psa_status_t mbedtls_psa_cipher_set_iv( psa_cipher_operation_t *operation,
const uint8_t *iv,
size_t iv_length )
{
mbedtls_psa_cipher_operation_t *mbedtls_ctx = &operation->ctx.mbedtls_ctx;
if( iv_length != mbedtls_ctx->iv_size )
return( PSA_ERROR_INVALID_ARGUMENT );
return( mbedtls_to_psa_error(
mbedtls_cipher_set_iv( &mbedtls_ctx->cipher,
iv, iv_length ) ) );
}
/* Process input for which the algorithm is set to ECB mode. This requires
* manual processing, since the PSA API is defined as being able to process
* arbitrary-length calls to psa_cipher_update() with ECB mode, but the
* underlying mbedtls_cipher_update only takes full blocks. */
static psa_status_t psa_cipher_update_ecb(
mbedtls_cipher_context_t *ctx,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length )
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
size_t block_size = ctx->cipher_info->block_size;
size_t internal_output_length = 0;
*output_length = 0;
if( input_length == 0 )
{
status = PSA_SUCCESS;
goto exit;
}
if( ctx->unprocessed_len > 0 )
{
/* Fill up to block size, and run the block if there's a full one. */
size_t bytes_to_copy = block_size - ctx->unprocessed_len;
if( input_length < bytes_to_copy )
bytes_to_copy = input_length;
memcpy( &( ctx->unprocessed_data[ctx->unprocessed_len] ),
input, bytes_to_copy );
input_length -= bytes_to_copy;
input += bytes_to_copy;
ctx->unprocessed_len += bytes_to_copy;
if( ctx->unprocessed_len == block_size )
{
status = mbedtls_to_psa_error(
mbedtls_cipher_update( ctx,
ctx->unprocessed_data,
block_size,
output, &internal_output_length ) );
if( status != PSA_SUCCESS )
goto exit;
output += internal_output_length;
output_size -= internal_output_length;
*output_length += internal_output_length;
ctx->unprocessed_len = 0;
}
}
while( input_length >= block_size )
{
/* Run all full blocks we have, one by one */
status = mbedtls_to_psa_error(
mbedtls_cipher_update( ctx, input,
block_size,
output, &internal_output_length ) );
if( status != PSA_SUCCESS )
goto exit;
input_length -= block_size;
input += block_size;
output += internal_output_length;
output_size -= internal_output_length;
*output_length += internal_output_length;
}
if( input_length > 0 )
{
/* Save unprocessed bytes for later processing */
memcpy( &( ctx->unprocessed_data[ctx->unprocessed_len] ),
input, input_length );
ctx->unprocessed_len += input_length;
}
status = PSA_SUCCESS;
exit:
return( status );
}
psa_status_t mbedtls_psa_cipher_update( psa_cipher_operation_t *operation,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length )
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
mbedtls_psa_cipher_operation_t *mbedtls_ctx = &operation->ctx.mbedtls_ctx;
size_t expected_output_size;
if( ! PSA_ALG_IS_STREAM_CIPHER( mbedtls_ctx->alg ) )
{
/* Take the unprocessed partial block left over from previous
* update calls, if any, plus the input to this call. Remove
* the last partial block, if any. You get the data that will be
* output in this call. */
expected_output_size =
( mbedtls_ctx->cipher.unprocessed_len + input_length )
/ mbedtls_ctx->block_size * mbedtls_ctx->block_size;
}
else
{
expected_output_size = input_length;
}
if( output_size < expected_output_size )
return( PSA_ERROR_BUFFER_TOO_SMALL );
if( mbedtls_ctx->alg == PSA_ALG_ECB_NO_PADDING )
{
/* mbedtls_cipher_update has an API inconsistency: it will only
* process a single block at a time in ECB mode. Abstract away that
* inconsistency here to match the PSA API behaviour. */
status = psa_cipher_update_ecb( &mbedtls_ctx->cipher,
input,
input_length,
output,
output_size,
output_length );
}
else
{
status = mbedtls_to_psa_error(
mbedtls_cipher_update( &mbedtls_ctx->cipher, input,
input_length, output, output_length ) );
}
return( status );
}
psa_status_t mbedtls_psa_cipher_finish( psa_cipher_operation_t *operation,
uint8_t *output,
size_t output_size,
size_t *output_length )
{
psa_status_t status = PSA_ERROR_GENERIC_ERROR;
mbedtls_psa_cipher_operation_t *mbedtls_ctx = &operation->ctx.mbedtls_ctx;
uint8_t temp_output_buffer[MBEDTLS_MAX_BLOCK_LENGTH];
if( mbedtls_ctx->cipher.unprocessed_len != 0 )
{
if( mbedtls_ctx->alg == PSA_ALG_ECB_NO_PADDING ||
mbedtls_ctx->alg == PSA_ALG_CBC_NO_PADDING )
{
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
}
status = mbedtls_to_psa_error(
mbedtls_cipher_finish( &mbedtls_ctx->cipher,
temp_output_buffer,
output_length ) );
if( status != PSA_SUCCESS )
goto exit;
if( *output_length == 0 )
; /* Nothing to copy. Note that output may be NULL in this case. */
else if( output_size >= *output_length )
memcpy( output, temp_output_buffer, *output_length );
else
status = PSA_ERROR_BUFFER_TOO_SMALL;
exit:
mbedtls_platform_zeroize( temp_output_buffer,
sizeof( temp_output_buffer ) );
return( status );
}
psa_status_t mbedtls_psa_cipher_abort( psa_cipher_operation_t *operation )
{
mbedtls_psa_cipher_operation_t *mbedtls_ctx = &operation->ctx.mbedtls_ctx;
/* Sanity check (shouldn't happen: operation->alg should
* always have been initialized to a valid value). */
if( ! PSA_ALG_IS_CIPHER( mbedtls_ctx->alg ) )
return( PSA_ERROR_BAD_STATE );
mbedtls_cipher_free( &mbedtls_ctx->cipher );
return( PSA_SUCCESS );
}
#endif /* MBEDTLS_PSA_CRYPTO_C */