mbedtls/programs/test/zeroize.c
2018-06-06 03:44:03 +01:00

102 lines
3 KiB
C

/*
* Zeroize application for debugger-driven testing
*
* This is a simple test application used for debugger-driven testing to check
* whether calls to mbedtls_platform_zeroize() are being eliminated by compiler
* optimizations. This application is used by the GDB script at
* tests/scripts/test_zeroize.gdb under the assumption that the code does not
* change often (as opposed to the library code) because the script sets a
* breakpoint at the last return statement in the main() function of this
* program. The debugger facilities are then used to manually inspect the
* memory and verify that the call to mbedtls_platform_zeroize() was not
* eliminated.
*
* 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.
*
* 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
#include <stdio.h>
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdlib.h>
#define mbedtls_printf printf
#define MBEDTLS_EXIT_SUCCESS EXIT_SUCCESS
#define MBEDTLS_EXIT_FAILURE EXIT_FAILURE
#endif
#include "mbedtls/platform_util.h"
#define BUFFER_LEN 1024
void usage( void )
{
mbedtls_printf( "Zeroize is a simple program to assist with testing\n" );
mbedtls_printf( "the mbedtls_platform_zeroize() function by using the\n" );
mbedtls_printf( "debugger. This program takes a file as input and\n" );
mbedtls_printf( "prints the first %d characters. Usage:\n\n", BUFFER_LEN );
mbedtls_printf( " zeroize <FILE>\n" );
}
int main( int argc, char** argv )
{
int exit_code = MBEDTLS_EXIT_FAILURE;
FILE *fp;
char buf[BUFFER_LEN];
char *p = buf;
char *end = p + BUFFER_LEN;
int c;
if( argc != 2 )
{
mbedtls_printf( "This program takes exactly 1 agument\n" );
usage();
return( exit_code );
}
fp = fopen( argv[1], "r" );
if( fp == NULL )
{
mbedtls_printf( "Could not open file '%s'\n", argv[1] );
return( exit_code );
}
while( ( c = fgetc( fp ) ) != EOF && p < end - 1 )
*p++ = (char)c;
*p = '\0';
if( p - buf != 0 )
{
mbedtls_printf( "%s\n", buf );
exit_code = MBEDTLS_EXIT_SUCCESS;
}
else
mbedtls_printf( "The file is empty!\n" );
fclose( fp );
mbedtls_platform_zeroize( buf, sizeof( buf ) );
return( exit_code );
}