BlueVeri: Formal Security Verification for Bluespec Processor Designs

Abstract

There are numerous hardware security defense mechanisms designed to mitigate sidechannel attacks. However, ensuring that a defense can comprehensively protect against an entire class of attacks, while avoiding the introduction of new vulnerabilities that could lead to additional attack surfaces, remains a significant challenge. Although researchers have attempted to apply formal verification techniques to hardware security, these efforts have been hindered by scalability issues. In this paper, we introduce BlueVeri, a systematic and automatable approach for formally verifying the security of a Bluespec processor against speculative execution attacks. BlueVeri leverages the high-level information provided by Bluespec’s guarded atomic actions, simplifying and accelerating the verification process. We evaluate BlueVeri on out-of-order processors implemented in Bluespec, demonstrating that our approach substantially enhances verification scalability and is capable of proving the security properties of a minimal out-of-order processor within one hour.