Paper 2017/998

A Comparative Investigation of Approximate Attacks on Logic Encryptions

Yuanqi Shen, Amin Rezaei, and Hai Zhou


Logic encryption is an important hardware protection technique that adds extra keys to lock a given circuit. With recent discovery of the effective SAT-based attack, new enhancement methods such as SARLock and Anti-SAT have been proposed to thwart the SAT-based and similar exact attacks. Since these new techniques all have very low error rate, approximate attacks such as Double DIP and AppSAT have been proposed to find an almost correct key with low error rate. However, measuring the performance of an approximate attack is extremely challenging, since exact computation of the error rate is very expensive, while estimation based on random sampling has low confidence. In this paper, we develop a suite of scientific encryption benchmarks where a wide range of error rates are possible and the error rate can be found out by simple eyeballing. Then, we conduct a thorough comparative study on different approximate attacks, including AppSAT and Double DIP. The results show that approximate attacks are far away from closing the gap and more investigations are needed in this area.

Available format(s)
Publication info
Preprint. MINOR revision.
logic encryptionSAT-based attackapproximate attack
Contact author(s)
haizhouus @ gmail com
2017-10-11: received
Short URL
Creative Commons Attribution


      author = {Yuanqi Shen and Amin Rezaei and Hai Zhou},
      title = {A Comparative Investigation of Approximate Attacks on Logic Encryptions},
      howpublished = {Cryptology ePrint Archive, Paper 2017/998},
      year = {2017},
      note = {\url{}},
      url = {}
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