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Hardware obfuscating is a proactive design-for-trust technique against IC supply chain threats, i.e., IP piracy and overproduction. Many studies have evaluated numerous techniques for obfuscation purposes. Nevertheless, de-obfuscation attacks have demonstrated their insufficiency. This paper proposes a register-transfer (RT) level finite-state-machine (FSM) obfuscation technique called ReTrustFSM that allows designers to obfuscate at the earliest possible stage. ReTrustFSM combines three types of secrecy: explicit external secrecy via an external key, implicit external secrecy based on specific clock cycles, and internal secrecy through a concealed FSM transition function. So, the robustness of ReTrustFSM relies on the external key, the external primary input patterns, and the cycle accuracy of applying such external stimuli. Additionally, ReTrustFSM defines a cohesive relationship between the features of Boolean problems and the required time for de-obfuscation, ensuring a maximum execution time for oracle-guided de-obfuscation attacks. Various attacks are employed to test ReTrustFSM’s robustness, including structural and machine learning attacks, functional I/O queries (BMC), and FSM attacks. We have also analyzed the corruptibility and overhead of design-under-obfuscation. Our experimental results demonstrate the robustness of ReTrustFSM at acceptable overhead/corruption while resisting such threat models.

In today’s Integrated Circuit (IC) production chains, a designer’s valuable Intellectual Property (IP) is transparent to diverse stakeholders and thus inevitably prone to piracy. To protect against this threat, numerous defenses based on the obfuscation of a circuit’s control path, i.e. Finite State Machine (FSM), have been proposed and are commonly believed to be secure. However, the security of these sequential obfuscation schemes is doubtful since realistic capabilities of reverse engineering and subsequent manipulation are commonly neglected in the security analysis. The contribution of our work is threefold: First, we demonstrate how high-level control path information can be automatically extracted from third-party, gate-level netlists. To this end, we extend state-of-the-art reverse engineering algorithms to deal with Field Programmable Gate Array (FPGA) gate-level netlists equipped with FSM obfuscation. Second, on the basis of realistic reverse engineering capabilities we carefully review the security of state-of-the-art FSM obfuscation schemes. We reveal several generic strategies that bypass allegedly secure FSM obfuscation schemes and we practically demonstrate our attacks for a several of hardware designs, including cryptographic IP cores. Third, we present the design and implementation of Hardware Nanomites, a novel obfuscation scheme based on partial dynamic reconfiguration that generically mitigates existing algorithmic reverse engineering.

The global market of developing Internet of Things (IoT) devices increases rapidly with improved design goals like cost, energy efficiency, and performance. Unfortunately, the above design goals often come at the expense of security. Illegal access to the network, malicious device control, compromised sensitive information, and theft of personal data are main threats to these devices. As a result, the Advanced Encryption Standard (AES) is sometimes employed to ensure safe transmission and processing of data in IoT Systems. However, tampering, cloning, and reverse engineering are main concerns that impair the computational complexity of the 128‐bit AES at the hardware level. Recently hardware obfuscation‐based AES has emerged as a comprehensive hardware security approach for reducing threat impacts. The hardware obfuscation schemes efficiently introduce obfuscation keys for AES to conceal its functionality. The Xilinx Vivado 2016.2 software and BASYS‐3 FPGA have been used to implement obfuscated AES approaches in this work. The proposed methods have low resource usage in terms of area and power overhead while providing a high level of security in terms of Hamming Distance of 50% and Avalanche Effect of 40% for each obfuscation method. We have also analyzed the probability of success for brute‐force attacks for proposed methodologies. [ABSTRACT FROM AUTHOR]