Hardware Trojans (HTs) are small circuits intentionally designed by an adversary for harmful purposes. These types of circuits are extremely difficult to detect. An HT often requires some specific signals to activate, which are almost impossible to discover. For this reason, test generation for side-channel analysis has gained significant attention in recent times and does not require HT activation. Such test generation techniques aim to generate a large amount of switching activity inside the HT circuit, increasing transient current measurement. However, such methods suffer from either long runtime or reliable results. In this work, a test generation technique is proposed based on the relative switching activity of the circuit to overcome the limitations of the existing works. Initially, the proposed technique measures the impact of each input on rare nets individually using random vector simulation. Potent inputs are selected to obtain a new set of test vectors that provide high relative switching inside a circuit. The proposed method is applied on 11 different ISCAS and 3 ITC 99 benchmark circuits. Experimental results endorse the efficacy of the proposed method outperforming traditional Hamming distance-based re-ordering techniques (up to 20×) while requiring a small runtime.

硬件木马 (HT) 是攻击者出于有害目的而故意设计的小电路。这些类型的电路极难检测。HT 通常需要一些特定的信号来激活，而这些信号几乎不可能被发现。因此，用于旁路分析的测试生成近年来受到了极大的关注，并且不需要 HT 激活。此类测试生成技术旨在在 HT 电路内部生成大量开关活动，从而增加瞬态电流测量。然而，此类方法要么运行时间长，要么结果可靠。在这项工作中，提出了一种基于电路的相对开关活动的测试生成技术，以克服现有工作的局限性。最初，所提出的技术使用随机矢量模拟来单独测量每个输入对稀有网络的影响。选择有效的输入以获得一组新的测试向量，这些向量在电路内部提供高相对切换。所提出的方法应用于 11 个不同的 ISCAS 和 3 个 ITC 99 基准电路。实验结果证明了所提出的方法的有效性优于传统的基于汉明距离的重新排序技术（高达 20×），同时需要较小的运行时间。