mbedtls/library/bignum_mod_raw.c
Janos Follath b7a88eca42 Bignum: Apply naming conventions
Numbers:

- A, B for mbedtls_mpi_uint* operands
- a, b for mbedtls_mpi_uint operands
- X or x for result
- HAC references where applicable

Lengths:

- Reserve size or length for length/size in bytes or byte buffers.
- For length of mbedtls_mpi_uint* buffers use limbs
- Length parameters are qualified if possible (eg. input_length or
  a_limbs)

Setup functions:

- The parameters match the corresponding structure member's name
- The structure to set up is a standard lower case name even if in other
  functions different naming conventions would apply

Scope of changes/conventions:

- bignum_core
- bignum_mod
- bignum_mod_raw

Signed-off-by: Janos Follath <janos.follath@arm.com>
2022-08-19 13:11:22 +01:00

98 lines
2.8 KiB
C

/*
* Multi-precision integer library
*
* 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_BIGNUM_C)
#include <string.h>
#include "mbedtls/error.h"
#include "mbedtls/platform_util.h"
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdio.h>
#include <stdlib.h>
#define mbedtls_printf printf
#define mbedtls_calloc calloc
#define mbedtls_free free
#endif
#include "bignum_core.h"
#include "bignum_mod_raw.h"
#include "bignum_mod.h"
#include "constant_time_internal.h"
int mbedtls_mpi_mod_raw_read( mbedtls_mpi_uint *X,
const mbedtls_mpi_mod_modulus *m,
const unsigned char *input,
size_t input_lentgth )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
switch( m->ext_rep )
{
case MBEDTLS_MPI_MOD_EXT_REP_LE:
ret = mbedtls_mpi_core_read_le( X, m->limbs,
input, input_lentgth );
break;
case MBEDTLS_MPI_MOD_EXT_REP_BE:
ret = mbedtls_mpi_core_read_be( X, m->limbs,
input, input_lentgth );
break;
default:
return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA );
}
if( ret != 0 )
goto cleanup;
if( !mbedtls_mpi_core_lt_ct( X, m->p, m->limbs ) )
{
ret = MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
goto cleanup;
}
cleanup:
return( ret );
}
int mbedtls_mpi_mod_raw_write( const mbedtls_mpi_uint *A,
const mbedtls_mpi_mod_modulus *m,
unsigned char *output,
size_t output_length )
{
switch( m->ext_rep )
{
case MBEDTLS_MPI_MOD_EXT_REP_LE:
return( mbedtls_mpi_core_write_le( A, m->limbs,
output, output_length ) );
case MBEDTLS_MPI_MOD_EXT_REP_BE:
return( mbedtls_mpi_core_write_be( A, m->limbs,
output, output_length ) );
default:
return( MBEDTLS_ERR_MPI_BAD_INPUT_DATA );
}
}
#endif /* MBEDTLS_BIGNUM_C */