Rescuing Hardware from malware attacks is a great challenge today. Moreover detecting the presence of malicious intrusion using low-cost techniques is very challenging especially when it is believed that hardware Trojans are integrated into the rarely excited nodes. Though logical testing is admitted to be the accurate way to check the functional correctness of the circuit, the method becomes inefficient for circuits requiring humongous number of test patterns to activate the hardware trojan. This paper proposes a probabilistic approach to generate a set of test patterns that activate the Trojan explicitly by observing the incorrect responses to the applied test patterns. Our experimental result in ISCAS’85 benchmark circuits show that the test patterns generated by our approach enclose all nets where there is a high chance for trojan insertion. We stress that though our results are circuit specific, the proposed approach is generic and hence it can be applied to any digital circuit. In fact, we demonstrate that for the C880 circuit, our approach requires only 217 inputs to be tested whereas the naive approach needs 260 test patterns. In addition to the experimental results, we use a game-theoretic framework to show the effectiveness of our approach in generating trojan activating test patterns compared to naive and ATPG testing process.

中文翻译：

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TRAP-GATE：一种增强硬件木马检测的概率方法及其博弈论分析

从恶意软件攻击中拯救硬件是当今的一项巨大挑战。此外，使用低成本技术检测恶意入侵的存在非常具有挑战性，尤其是当人们认为硬件木马被集成到很少被激活的节点时。虽然逻辑测试被认为是检查电路功能正确性的准确方法，但对于需要大量测试模式来激活硬件木马的电路来说，该方法效率低下。本文提出了一种概率方法来生成一组测试模式，通过观察对应用测试模式的不正确响应来显式激活木马。我们在 ISCAS'85 基准电路中的实验结果表明，由我们的方法生成的测试模式包含所有网络，那里有很高的木马插入机会。我们强调，虽然我们的结果是特定于电路的，但所提出的方法是通用的，因此它可以应用于任何数字电路。事实上，我们证明了对于 C880 电路，我们的方法只需要测试 217 个输入，而朴素的方法需要 260 个测试模式。除了实验结果之外，我们还使用博弈论框架来展示我们的方法在生成木马激活测试模式方面的有效性，与朴素和 ATPG 测试过程相比。