Biblio

The manufacturing of integrated circuits (IC) outside of the design houses makes it possible for the adversary to easily perform a reverse engineering attack against intellectual property (IP)/IC. The aim of this attack can be the IP piracy, overproduction, counterfeiting or inserting hardware Trojan (HT) throughout the supply chain of the IC. Preventing hardware Trojan insertion is a significant issue in the context of hardware security (HS) and has not been considered in most of the previous logic encryption methods. To eliminate this problem, in this paper an Anti-Trojan insertion algorithm is presented. The idea is based on the fact that reducing the signals with low-observability (LO) and low-controllability (LC) can prevent HT insertion significantly. The security of logic encryption methods depends on the algorithm and the encryption key. However, the security of these methods has been compromised by SAT attacks over recent years. SAT attacks, can decode the correct key from most logic encryption techniques. In this article, by using the PUF-based encryption, the applied key in the encryption is randomized and SAT attack cannot be performed. Based on the output of PUF, a unique encryption has been made for each chip that preventing from counterfeiting and IP piracy.

Hardware Trojan threats caused by malicious designers and untrusted manufacturers have become one of serious issues in modern VLSI systems. In this paper, we show some experimental results to insert hardware Trojans into asynchronous circuits. As a result, the overhead of hardware Trojan insertion in asynchronous circuits may be small for malicious designers who have enough knowledge about the asynchronous circuits. In addition, we also show several Trojan detection methods using deep learning schemes which have been proposed to detect synchronous hardware Trojan in the netlist level. We apply them to asynchronous hardware Trojan circuits and show their results. They have a great potential to detect a hardware Trojan in asynchronous circuits.

The threats of reverse-engineering, IP piracy, and hardware Trojan insertion in the semiconductor supply chain are greater today than ever before. Split manufacturing has emerged as a viable approach to protect integrated circuits (ICs) fabricated in untrusted foundries, but has high cost and/or high performance overhead. Furthermore, split manufacturing cannot fully prevent untargeted hardware Trojan insertions. In this paper, we propose to insert additional functional circuitry called obfuscated built-in self-authentication (OBISA) in the chip layout with split manufacturing process, in order to prevent reverse-engineering and further prevent hardware Trojan insertion. Self-tests are performed to authenticate the trustworthiness of the OBISA circuitry. The OBISA circuit is connected to original design in order to increase the strength of obfuscation, thereby allowing a higher layer split and lower overall cost. Additional fan-outs are created in OBISA circuitry to improve obfuscation without losing testability. Our proposed gating mechanism and net selection method can ensure negligible overhead in terms of area, timing, and dynamic power. Experimental results demonstrate the effectiveness of the proposed technique in several benchmark circuits.