Functional Analysis Attacks on Logic Locking

This paper proposes Functional Analysis attacks on state of the art Logic Locking algorithms (Fall attacks). Fall attacks use structural and functional analyses of locked circuits to identify the locking key. In contrast to past work, Fall attacks can often (90% of successful attempts in our experiments) fully defeat locking by only analyzing the locked netlist, without oracle access to an activated circuit. Experiments show that Fall attacks succeed against 65 out of 80 (81%) of circuits locked using Secure Function Logic Locking (SFLL), the only combinational logic locking algorithm resilient to all known attacks.