Towards the Detection of Hardware Trojans with Cost Effective Test Vectors using Genetic Algorithm

Hardware Trojans (HT) are tiny circuits designed to exploit electronic devices, posing risks such as device malfunction or leakage of sensitive information. The adversary aims to implant these HTs specifically targeting nets with minimal signal transition (rare gates) within a circuit, evading detection during functional tests. Some Trojan variants are activated by adversaries under specific periodic conditions. Logic testing, a well-established method for test generation in HT detection, faces challenges due to the impractical scale of the search space, whereas Genetic Algorithms (GA) excel in efficiently navigating extensive solution spaces. This paper presents a GA-based technique that integrates information on effective inputs, along with an adequate fitness function defined based on combinational controllability and structural features, for detecting conditionally triggered ultrasmall HTs. Upon assessing the ITC 99 and ISCAS 85 and 89 benchmarks, we note significant enhancements in trigger coverage and reduced run-time requirements in comparison to state-of-the-art methods like MERO and TRIAGE.