1. Introduction to Hardware Obfuscation: Motivation, Methods and Evaluation

While the globalization of the semiconductor production process has accelerated innovation, lowered costs, and reduced time-to-market, it has also created grave trust issues among the different entities involved in the production process. Theft, reverse engineering, and piracy of silicon intellectual property (IP) are the realities that manufacturers and vendors of integrated circuits must face today. In order to combat these threats, obfuscation has emerged as a viable candidate for semiconductor or hardware IP protection. Obfuscation techniques aim at concealing or locking the underlying intellectual property of a semiconductor product, such as IP cores, gate-level designs, or layout, in order to prevent an untrusted party or adversary from reverse engineering and/or exploiting the design. In this chapter, we will review emerging techniques for hardware obfuscation. We will describe the semiconductor supply chain in detail and outline the specific threats associated with each stage in the supply chain. We will also introduce the field of software obfuscation and related concepts that predate hardware obfuscation. Lastly, we will introduce relevant metrics for implementing and evaluating the various hardware obfuscation techniques.