A PCA and Mahalanobis distance‐based detection method for logical hardware Trojan

Abstract

Due to wide application of FPGA devices, which are easy to be attacked by HTs, it has been risen up more concern on chip security. In order to ensure the efficiency of detection, side-channel analysis is used to detect HTs. However, existing methods for HT detection cannot detect the LHTs with the small size, which takes up lower than 1% area of the whole chip, considering that signal of LHTs is drowned in process deviations. To complete the side-channel analysis for LHT, we proposed an algorithm that combines PCA and Mahalanobis distance to improve the accuracy of LHTs detection. In addition, performed on FPGA of Xilinx, a sample of LHTs was designed and verified, which took up nearly 0.1% area of the whole chip. The influence of process deviation on the power consumption of FPGA was simulated by Hspice. A set of power-frequency data of golden FPGA was generated by Matlab as panel data, which was considering the influence. Another two sets of FPGA with and without LHT were generated to test the accuracy of the proposed method. For LHT and golden FPGA, the detection accuracy of proposed method is 99% and 87%, respectively. KEYWORDS detection methods, hardware security, hardware trojans, side-channel analysis INTRODUCTIONWith the increasingly complex design of integrated circuits, the cost of manufacturing is becoming higher, and integrated circuits industry is developing toward global cooperation. Due to the outsourced fabrication, assembly, and testing, the security of integrated circuits is facing a new challenge, which is the emergence of HTs. They are stealthy malicious modifications on the original circuits. 1An HT is composed of trigger and payload circuit. The trigger circuit determines the condition when HT is activated. 2 When HT is activated, payload circuit causes functional tampering, downgrade performance, leakage information, or denial of service problem. 3 Frey and Yu concluded that, as the development of HT design, it will be more difficult to detect them. 4 A wireless bypass hardware Trojan is designed by Jin and Makris for the first time in a digital analog hybrid circuit based on the analog characteristics of the wireless channel, such as amplitude, frequency, and phase.This hardware realized depth concealment. 5 Zhang and Xu proposed a systematic hardware Trojan design and implementation methodology, which makes the HT not only hard to trigger but also easy to evade existing detection techniques based on 'unused circuit identification ' . 6 Existing efforts on HT detection can be divided into destructive and nondestructive methods. The destructive method is mainly based on cutting molding coat to reveal the circuit, using SEM to observe the surfaces while grinding the layers of the chip, comparing the image to origin circuit in order to examine the fingerprint. 7 For the chips with simple structure, the destructive method is more suitable. The cost and time consumption of detection will be huge when the structure of chips is complex. The nondestructive detection methods include functional t...