SAT‐based Bit‐flipping Attack on Logic Encryptions
Yuanqi Shena, Amin Rezaeib and Hai Zhouc
Northwestern University
ayuanqishen2020@u.northwestern.edu
bme@aminrezaei.com
chaizhou@northwestern.edu
ABSTRACT
Logic encryption is a hardware security technique that uses extra key inputs to prevent unauthorized use of a circuit. With the discovery of the SAT‐based attack, new encryption techniques such as SARLock and Anti‐SAT are proposed, and further combined with traditional logic encryption techniques, to guarantee both high error rates and resilience to the SAT‐based attack. In this paper, the SAT‐based bit‐flipping attack is presented. It first separates the two groups of keys via SAT‐based bit‐flippings, and then attacks the traditional encryption and the SAT‐resilient encryption, by conventional SAT‐based attack and by‐passing attack, respectively. The experimental results show that the bit‐flipping attack successfully returns a circuit with the correct functionality and significantly reduces the execution time compared with other advanced attacks.
