#include <windows.h>

int main( int nArgc, char** lpszArgv )
{
	if( nArgc == 1 )
	{
		return 0;
	}

	HANDLE hFile = CreateFileA( lpszArgv[ 1 ], GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL );

	if( hFile == INVALID_HANDLE_VALUE )
	{
		return 0;
	}

	DWORD dwFileSize = GetFileSize( hFile, NULL );
	BYTE* lpyBuffer = new BYTE[ dwFileSize ];

	DWORD dwRead;
	ReadFile( hFile, lpyBuffer, dwFileSize, &dwRead, NULL );
	CloseHandle( hFile );

	for( DWORD i = 0; i < dwFileSize; i++ )
	{
		lpyBuffer[ i ] = ( lpyBuffer[ i ] - 0x6C ) ^ 0x49;
	}

	lpyBuffer[ 1 ] += 0xF0;

	char szPath[ MAX_PATH ] = "";
	strcpy_s( szPath, lpszArgv[ 1 ] );
	*strrchr( szPath, '.') = '\0';
	strcat_s( szPath, "decrypted.dll" );

	hFile = CreateFileA( szPath, GENERIC_WRITE, FILE_SHARE_WRITE, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL );
	WriteFile( hFile, lpyBuffer, dwFileSize, &dwRead, NULL );
	CloseHandle( hFile );

	return 0;
}