Slicing Aided Design of Obfuscating Transforms

An obfuscation aims to transform a program, without affecting its functionality, so that some secret information within the program can be hidden for as long as possible from an adversary armed with reverse engineering tools. Slicing is a reverse engineering technique which aims to produce a subset of a program which is dependent on a particular program point and is used to aid in program comprehension. Thus slicing could be used as a way of attacking obfuscated programs. Can we design obfuscations which are more resilient to slicing attacks? In this paper we present a novel approach to creating obfuscating transforms which are designed to survive slicing attacks. We show how we can utilise the information gained from slicing a program to aid us in manufacturing obfuscations that are more resistant to slicing. We give a definition for what it means for a transformation to be a slicing obfuscation and we illustrate our approach with a number of obfuscating transforms.