Trojan-D2: Post-Layout Design and Detection of Stealthy Hardware Trojans - a RISC-V Case Study

With the exponential increase in the popularity of the RISC-V ecosystem, the security of this platform must be re-evaluated especially for mission-critical and IoT devices. Besides, the insertion of a Hardware Trojan (HT) into a chip after the in-house mask design is outsourced to a chip manufacturer abroad for fabrication is a significant source of concern. Though abundant HT detection methods have been in-vestigated based on side-channel analysis, physical measurements, and functional testing to overcome this problem, there exists stealthy HTs that can hide from detection. This is due to the small overhead of such HTs compared to the whole circuit. In this work, we propose several novel HTs that can be placed into a RISC-V core's post-layout in an untrusted manufacturing environment. Next, we propose a non-invasive analytical method based on contactless optical probing to detect any stealthy HTs. Finally, we propose an open-source library of HTs that can be used to be placed into a processor unit in the post-layout phase. All the designs in this work are done using a commercial 28nm technology.