Hardware Trojan Free Netlist Identification: A Clustering Approach

Hardware Trojans (HT) have emerged as a significant threat to both the IC industry and the military due to their stealthy nature and destructive capabilities. An HT is a small piece of hardware (circuit) embedded by an adversary to disrupt the victim circuit's regular operation. As a result, it becomes an utmost necessity to distinguish standard signals from them. The detection of HT has become critical due to the presence of enormous search space combined with its small size. A clustering-based approach is proposed to identify benign signals in this work. The proposed approach combines both transition probability and combinational controllability to generate an effective HT free whitelist. It reduces the overhead of search space for HT detection. The clusters generated (whitelist) are analyzed in the presence of several ultra-small triggers which advocates the efficacy of the proposed solution. Simulation results on various ISCAS benchmark circuits validate the significance and quality of such clusters in terms of observed transition. Experimental results also underpin the proposed methodology's superiority over existing techniques by identifying proper whitelist easily.