Obfuscation-Based Secure SoC Design for Protection Against Piracy and Trojan Attacks

System-on-Chip (SoC) designs rely heavily on reusable and pre-verified hardware intellectual property (IP) cores. Recent trends of IP piracy and reverse-engineering, and malicious circuit modifications (“hardware Trojans”) in remote fabrication facilities, are major concerns. In this chapter, we propose a comprehensive secure SoC design flow based on the principle of design obfuscation that can provide effective protection against IP piracy as well as hardware Trojan attacks. We present the overall approach and illustrate the obfuscation process with an example. We provide a brief survey of related work on hardware obfuscation and then present two variations of obfuscation, which differ in the level of protection and the complexity of implementation. The first approach is based on extraction and modification of the state transition from the gate-level synthesized design, such that normal operation is possible only on the successful application of a correct initialization sequence. Optionally, an obfuscated register transfer level (RTL) design can be generated by de-compilation of the obfuscated netlist. In the second approach, a register transfer level IP is obfuscated by manipulating its control and data flow graphs. The proposed approaches are scalable, and can be integrated in the SoC design and manufacturing flow to benefit all parties associated with the design flow, while minimally affecting the end-user experience.