mbedtls/programs/random/gen_entropy.c
2018-06-14 23:01:55 +01:00

101 lines
2.7 KiB
C

/**
* \brief Use and generate multiple entropies calls into a file
*
* 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)
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdio.h>
#include <stdlib.h>
#define mbedtls_fprintf fprintf
#define mbedtls_printf printf
#define MBEDTLS_EXIT_SUCCESS EXIT_SUCCESS
#define MBEDTLS_EXIT_FAILURE EXIT_FAILURE
#endif /* MBEDTLS_PLATFORM_C */
#if defined(MBEDTLS_ENTROPY_C) && defined(MBEDTLS_FS_IO)
#include "mbedtls/entropy.h"
#include <stdio.h>
#endif
#if !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_FS_IO)
int main( void )
{
mbedtls_printf("MBEDTLS_ENTROPY_C and/or MBEDTLS_FS_IO not defined.\n");
return( 0 );
}
#else
int main( int argc, char *argv[] )
{
FILE *f;
int i, k, ret = 1;
int exit_code = MBEDTLS_EXIT_FAILURE;
mbedtls_entropy_context entropy;
unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
if( argc < 2 )
{
mbedtls_fprintf( stderr, "usage: %s <output filename>\n", argv[0] );
return( exit_code );
}
if( ( f = fopen( argv[1], "wb+" ) ) == NULL )
{
mbedtls_printf( "failed to open '%s' for writing.\n", argv[1] );
return( exit_code );
}
mbedtls_entropy_init( &entropy );
for( i = 0, k = 768; i < k; i++ )
{
ret = mbedtls_entropy_func( &entropy, buf, sizeof( buf ) );
if( ret != 0 )
{
mbedtls_printf( " failed\n ! mbedtls_entropy_func returned -%04X\n",
ret );
goto cleanup;
}
fwrite( buf, 1, sizeof( buf ), f );
mbedtls_printf( "Generating %ldkb of data in file '%s'... %04.1f" \
"%% done\r", (long)(sizeof(buf) * k / 1024), argv[1], (100 * (float) (i + 1)) / k );
fflush( stdout );
}
exit_code = MBEDTLS_EXIT_SUCCESS;
cleanup:
mbedtls_printf( "\n" );
fclose( f );
mbedtls_entropy_free( &entropy );
return( exit_code );
}
#endif /* MBEDTLS_ENTROPY_C */