Runtime Trust Evaluation and Hardware Trojan Detection Using On-Chip EM Sensors

It has been widely demonstrated that the utilization of postdeployment trust evaluation approaches, such as side-channel measurements, along with statistical analysis methods is effective for detecting hardware Trojans in fabricated integrated circuits (ICs). However, more sophisticated Trojans proposed recently invalidate these methods with stealthy triggers and very-low side-channel signatures. Upon these challenges, in this paper, we propose an electromagnetic (EM) side-channel based post-fabrication trust evaluation framework which monitors EM radiations at runtime. The key component of the runtime trust evaluation framework is an on-chip EM sensor which can constantly measure and collect EM side-channel information of the target circuit. The simulation results validate the capability of the proposed framework in detecting stealthy hardware Trojans. Further, we fabricate an AES circuit protected by the proposed trust evaluation framework along with four different types of hardware Trojans. The measurements on the fabricated chips prove two key findings. First, the on-chip EM sensor can achieve a higher signal to noise ratio (SNR) and thus facilitate a better Trojan detection accuracy. Second, the trust evaluation framework can help detect different hardware Trojans at runtime.