Paper 2017/621

Novel Bypass Attack and BDD-based Tradeoff Analysis Against all Known Logic Locking Attacks

Xiaolin Xu, Bicky Shakya, Mark M. Tehranipoor, and Domenic Forte


Logic locking has emerged as a promising technique for protecting gate-level semiconductor intellectual property. However, recent work has shown that such gate-level locking techniques are vulnerable to Boolean satisfiability (SAT) attacks. In order to thwart such attacks, several SAT-resistant logic locking techniques have been proposed, which minimize the discriminating ability of input patterns to rule out incorrect keys. In this work, we show that such SAT-resistant logic locking techniques have their own set of unique vulnerabilities. In particular, we propose a novel ``bypass attack" that ensures the locked circuit works even when an incorrect key is applied. Such a technique makes it possible for an adversary to be oblivious to the type of SAT-resistant protection applied on the circuit, and still be able to restore the circuit to its correct functionality. We show that such a bypass attack is feasible on a wide range of benchmarks and SAT-resistant techniques, while incurring minimal run-time and area/delay overhead. Binary decision diagrams (BDDs) are utilized to analyze the proposed bypass attack and assess tradeoffs in security vs overhead of various countermeasures.

Available format(s)
Publication info
A minor revision of an IACR publication in CHES 2017
Logic LockingSAT AttackHardware IP ProtectionHardware Security
Contact author(s)
xiaolinxu @ ece ufl edu
2017-06-27: received
Short URL
Creative Commons Attribution


      author = {Xiaolin Xu and Bicky Shakya and Mark M.  Tehranipoor and Domenic Forte},
      title = {Novel Bypass Attack and BDD-based Tradeoff Analysis Against all Known Logic Locking Attacks},
      howpublished = {Cryptology ePrint Archive, Paper 2017/621},
      year = {2017},
      note = {\url{}},
      url = {}
Note: In order to protect the privacy of readers, does not use cookies or embedded third party content.