Run-Time Detection of Hardware Trojan Attacks on Program Counter in RISC-V Processor

Protection against hardware security issues like Hardware Trojans (HTs) in Integrated Circuits (ICs) is a major concern. Safeguarding crucial assets of the microprocessor has become vital in order to protect its functionality so that adversaries do not have any illegal privileges over the system. One such crucial asset is Program Counter (PC) and in this paper a run-time detection mechanism is presented to detect attacks against PC. The common drawback observed was not being able to detect those trojan attacks that caused the processor to crash and thereby the system to hang, which is addressed by the proposed mechanism. Those HTs that affect the execution of the instruction flow are also detected with the same mechanism. Implemented on a single-cycle RISC-V processor, the detection latency measured was one clock cycle. Area overhead, change in power consumption, change in working frequency were measured and the types of HTs that could be detected using this detection mechanism were analysed.