Protecting Reprogrammable Hardware with Polymorphic Circuit Variation ∗

Cyperspace is constantly threatened by attackers and malware that focus their attacks on a set of known vulnerabilities. When a sequence of software code or hardware structure is exposed, it can reveal new vulnerabilities and weaken embedded protections. Attacks on existing code sequences or hardware structure will be less effective if we can provide sufficient protection. Though software protection is an open problem with known theoretical limits, practitioners seek to find ways of expressing time or cost metrics induced by various techniques on malicious reverse engineers and adversarial analysis. In this paper we consider the nature of circuit transformation algorithms that operate on programmatic logic using iterative sequences of probabilistic and deterministic transforms. We consider such algorithms from the perspective of the kinds of information relative to circuits we are interested in hiding or protecting and experimental results along those lines.