Interpreting Opacity in the Context of Information-hiding and Obfuscation in Distributed Systems

The concept of opacity has been investigated in two different contexts as means of expressing security properties in distributed systems. Opacity in the context of information-hiding assumes the existence of a black-box and is concerned with enforcing properties such as anonymity and secrecy on collaborating processes in an untrusted distributed computing environment. In the context of software obfuscation, opacity is a measure of the difficulty of reverse engineering of object code under the assumption that the adversary has access to grey-box information. In this contribution, we bring together these two contexts in which opacity has been defined and discuss how a specialized technique, called opaque predicates, can deter malicious reverse engineering