Advancing Hardware Security Using Polymorphic and Stochastic Spin-Hall Effect Devices

TL;DR

This paper introduces a novel spin-Hall effect device that enhances hardware security by enabling polymorphic and stochastic functions, providing robust protection against SAT and side-channel attacks with minimal overhead.

Contribution

It presents a new primitive based on GSHE switches that combines locking and camouflaging in a single device, improving security and efficiency over existing methods.

Findings

The primitive can cloak all 16 two-input Boolean functions.

It demonstrates superior resilience to SAT attacks compared to prior techniques.

Stochastic operation can further thwart SAT-based and side-channel attacks.

Abstract

Protecting intellectual property (IP) in electronic circuits has become a serious challenge in recent years. Logic locking/encryption and layout camouflaging are two prominent techniques for IP protection. Most existing approaches, however, particularly those focused on CMOS integration, incur excessive design overheads resulting from their need for additional circuit structures or device-level modifications. This work leverages the innate polymorphism of an emerging spin-based device, called the giant spin-Hall effect (GSHE) switch, to simultaneously enable locking and camouflaging within a single instance. Using the GSHE switch, we propose a powerful primitive that enables cloaking all the 16 Boolean functions possible for two inputs. We conduct a comprehensive study using state-of-the-art Boolean satisfiability (SAT) attacks to demonstrate the superior resilience of the proposed primitive in comparison to several others in the literature. While we tailor the primitive for deterministic computation, it can readily support stochastic computation; we argue that stochastic behavior can break most, if not all, existing SAT attacks. Finally, we discuss the resilience of the primitive against various side-channel attacks as well as invasive monitoring at runtime, which are arguably even more concerning threats than SAT attacks.