libewf_common.c

sleuthit-2.09 一个磁盘的工具集

/*
 * Common code for libewf - wraps external function calls
 *
 * Copyright (c) 2006-2007, Joachim Metz <[e-mail]>,
 * Hoffmann Investigations. All rights reserved.
 *
 * Refer to AUTHORS for acknowledgements.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 * - Neither the name of the creator, related organisations, nor the names of
 *   its contributors may be used to endorse or promote products derived from
 *   this software without specific prior written permission.
 * - All advertising materials mentioning features or use of this software
 *   must acknowledge the contribution by people stated in the acknowledgements.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER, COMPANY AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "libewf_includes.h"

#ifdef HAVE_STRING_H
#include <string.h>
#endif

#include <libewf/libewf_definitions.h>

#include "libewf_common.h"
#include "libewf_notify.h"

#if defined( HAVE_WINDOWS_API )
#define libewf_common_strerror_r( error_number, string, size ) \
	strerror_s( string, size, error_number )

#define LIBEWF_COMMON_STRERROR_R_RETURN_ERROR	0

#elif defined( HAVE_STRERROR_R )
#define libewf_common_strerror_r( error_number, string, size ) \
	strerror_r( error_number, string, size )

#if defined( STRERROR_R_CHAR_P )
#define LIBEWF_COMMON_STRERROR_R_RETURN_ERROR	NULL
#else
#define LIBEWF_COMMON_STRERROR_R_RETURN_ERROR	0
#endif

#endif

/* Function to wrap strerror()
 * Returns a new instance to a string containing the error string, NULL on error
 */
char *libewf_common_strerror( int error_number )
{
#if !defined( libewf_common_strerror_r ) && defined( HAVE_STRERROR )
	char *static_error_string = NULL;
#endif
#if defined( libewf_common_strerror_r ) || defined( HAVE_STRERROR )
	char *error_string        = NULL;
	size_t error_string_size  = 256;

	error_string = (char *) libewf_common_alloc( error_string_size * sizeof( char ) );

	if( error_string == NULL )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_strerror: unable to create error string.\n" );

		return( NULL );
	}
#endif
#if defined( libewf_common_strerror_r )
	if( libewf_common_strerror_r( error_number, error_string, error_string_size ) != LIBEWF_COMMON_STRERROR_R_RETURN_ERROR )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_strerror: unable to set error string.\n" );

		libewf_common_free( error_string );

		return( NULL );
	}
	return( error_string );
#elif defined( HAVE_STRERROR )
	static_error_string = strerror( error_number );

	if( static_error_string == NULL )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_strerror: unable to create static error string.\n" );

		libewf_common_free( error_string );

		return( NULL );
	}
	if( libewf_common_string_copy( error_string, static_error_string, error_string_size ) == NULL )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_strerror: unable to set error string.\n" );

		libewf_common_free( error_string );

		return( NULL );
	}
	return( error_string );
#else
	return( NULL );
#endif
}

#if defined( HAVE_WIDE_CHARACTER_TYPE ) && defined( HAVE_WIDE_CHARACTER_SUPPORT_FUNCTIONS )

#if defined( HAVE_WINDOWS_API )
#define libewf_common_wide_strerror_r( error_number, string, size ) \
	_wcserror_s( string, size, error_number )

#define LIBEWF_COMMON_WIDE_STRERROR_R_RETURN_ERROR	0

#else
#error Missing wide character equivalent of strerror()
#endif

/* Function to wrap wide character equivalent of strerror()
 * Returns a new instance to a string containing the error string, NULL on error
 */
wchar_t *libewf_common_wide_strerror( int error_number )
{
#if defined( libewf_wide_common_strerror_r )
	wchar_t *error_string      = NULL;
	uint16_t error_string_size = 256;

	error_string = (wchar_t *) libewf_common_alloc( error_string_size * sizeof( wchar_t ) );

	if( error_string == NULL )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_wide_strerror: unable to create error string.\n" );

		return( NULL );
	}
	if( libewf_common_strerror_r( error_number, error_string, error_string_size ) != LIBEWF_COMMON_STRERROR_R_RETURN_ERROR )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_wide_strerror: unable to set error string.\n" );

		libewf_common_free( error_string );

		return( NULL );
	}
	return( error_string );
#else
	return( NULL );
#endif
}
#endif

/* Function to wrap open()
 */
int libewf_common_open( const char *filename, uint8_t flags )
{
#if defined( HAVE_WINDOWS_API )
	int file_descriptor  = 0;
#endif
	int open_flags       = 0;

	if( filename == NULL )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_open: invalid filename.\n" );

		return( -1 );
	}
	if( flags == LIBEWF_OPEN_READ )
	{
#if defined( HAVE_WINDOWS_API )
		open_flags = _O_RDONLY | _O_BINARY;
#else
		open_flags = O_RDONLY;
#endif
	}
	else if( flags == LIBEWF_OPEN_WRITE )
	{
#if defined( HAVE_WINDOWS_API )
		open_flags = _O_WRONLY | _O_CREAT | _O_TRUNC | _O_BINARY;
#else
		open_flags = O_WRONLY | O_CREAT | O_TRUNC;
#endif
	}
	else if( flags == LIBEWF_OPEN_READ_WRITE )
	{
#if defined( HAVE_WINDOWS_API )
		open_flags = _O_RDWR | _O_BINARY;
#else
		open_flags = O_RDWR ;
#endif
	}
	else
	{
		LIBEWF_WARNING_PRINT( "libewf_common_open: flags not supported.\n" );

		return( -1 );
	}
#if defined( HAVE_WINDOWS_API )
	if( _sopen_s( &file_descriptor, filename, open_flags, _SH_DENYRW, ( _S_IREAD | _S_IWRITE ) ) != 0 )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_open: error opening file.\n" );

		return( -1 );
	}
	return( file_descriptor );
#else
	return( open( filename, open_flags, 0644 ) );
#endif
}

#if defined( HAVE_WIDE_CHARACTER_TYPE ) && defined( HAVE_WIDE_CHARACTER_SUPPORT_FUNCTIONS )

/* Function to wrap wide character equivalent of open()
 */
int libewf_common_wide_open( const wchar_t *filename, uint8_t flags )
{
#if defined( HAVE_WINDOWS_API )
	int file_descriptor  = 0;
#endif
	int open_flags       = 0;

	if( filename == NULL )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_wide_open: invalid filename.\n" );

		return( -1 );
	}
	if( flags == LIBEWF_OPEN_READ )
	{
#if defined( HAVE_WINDOWS_API )
		open_flags = _O_RDONLY | _O_BINARY;
#else
		open_flags = O_RDONLY;
#endif
	}
	else if( flags == LIBEWF_OPEN_WRITE )
	{
#if defined( HAVE_WINDOWS_API )
		open_flags = _O_WRONLY | _O_CREAT | _O_TRUNC | _O_BINARY;
#else
		open_flags = O_WRONLY | O_CREAT | O_TRUNC;
#endif
	}
	else if( flags == LIBEWF_OPEN_READ_WRITE )
	{
#if defined( HAVE_WINDOWS_API )
		open_flags = _O_RDWR | _O_BINARY;
#else
		open_flags = O_RDWR ;
#endif
	}
	else
	{
		LIBEWF_WARNING_PRINT( "libewf_common_wide_open: flags not supported.\n" );

		return( -1 );
	}
#if defined( HAVE_WINDOWS_API )
	if( _wsopen_s( &file_descriptor, filename, open_flags, _SH_DENYRW, ( _S_IREAD | _S_IWRITE ) ) != 0 )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_wide_open: error opening file.\n" );

		return( -1 );
	}
	return( file_descriptor );
#else
#error libewf_common_wide_open: missing wide character equivalent of open()
#endif
}
#endif

/* Function to allocated wiped memory
 */
void *libewf_common_alloc_cleared( size_t size, int clear_value )
{
	void *allocated_buffer = NULL;

	allocated_buffer = libewf_common_alloc( size );

	if( allocated_buffer == NULL )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_alloc_cleared: unable to allocate buffer.\n" );

		return( NULL );
	}
	if( size > (size_t) SSIZE_MAX )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_alloc_cleared: invalid size value exceeds maximum.\n" );

		return( NULL );
	}
	if( libewf_common_memset( allocated_buffer, clear_value, size ) == NULL )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_alloc_cleared: unable to clear buffer.\n" );

		libewf_common_free( allocated_buffer );

		return( NULL );
	}
	return( allocated_buffer );
}

/* Function to reallocated fully wiped memory
 */
void *libewf_common_realloc_full_cleared( void *buffer, size_t previous_size, size_t new_size, int clear_value )
{
	void *reallocated_buffer = NULL;

	if( ( previous_size > (size_t) SSIZE_MAX ) || ( new_size > (size_t) SSIZE_MAX ) )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_realloc_full_cleared: invalid size value exceeds maximum.\n" );

		return( NULL );
	}
	if( new_size <= previous_size )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_realloc_full_cleared: new size must be greater than previous size.\n" );

		return( NULL );
	}
	reallocated_buffer = libewf_common_realloc( buffer, new_size );

	if( reallocated_buffer == NULL )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_realloc_full_cleared: unable to reallocate buffer.\n" );

		return( NULL );
	}
	if( libewf_common_memset( reallocated_buffer, clear_value, new_size ) == NULL )
	{
		LIBEWF_WARNING_PRINT( "libewf_common_realloc_full_cleared: unable to clear buffer.\n" );

		libewf_common_free( reallocated_buffer );

		return( NULL );