DTA-PUF: Dynamic Timing-aware Physical Unclonable Function for Resource-constrained Devices

Abstract

In recent years, physical unclonable functions (PUFs) have gained a lot of attention as mechanisms for hardware-rooted device authentication. While the majority of the previously proposed PUFs derive entropy using dedicated circuitry, software PUFs achieve this from existing circuitry in a system. Such software-derived designs are highly desirable for low-power embedded systems as they require no hardware overhead. However, these software PUFs induce considerable processing overheads that hinder their adoption in resource-constrained devices. In this article, we propose DTA-PUF, a novel, software PUF design that exploits the instruction- and data-dependent dynamic timing behaviour of pipelined cores to provide a reliable challenge-response mechanism without requiring any extra hardware. DTA-PUF accepts sequences of instructions as an input challenge and produces an output response based on the manifested timing errors under specific over-clocked settings. To lower the required processing effort, we systematically select instruction sequences that maximise error-rate. The application to a post-layout pipelined floating-point unit, which is implemented in 45 nm process technology, demonstrates the effectiveness and practicability of our PUF design. Finally, DTA-PUF requires up to 50× fewer instructions than existing software processor PUF designs, limiting processing costs and resulting in up to 26% power savings.

Novel Intrinsic Physical Unclonable Function Design for Post-quantum Cryptography

“…J. Kong proposed ALU PUF [3] based on the delay difference in two different ALUs. Tsiokanos proposed DTA-PUF [6], an intrinsic PUF design that exploits the instruction-and data-dependent dynamic timing behavior of pipelined cores.…”

“…For example, the PUF in [4] presented poor uniqueness and less CRP generation efficiency. DTA-PUF [6] has high CRP generation efficiency but also having poor uniqueness.…”

RPPUF: An Ultra-Lightweight Reconfigurable Pico-Physically Unclonable Function for Resource-Constrained IoT Devices

“…Although LR PUFs can improve the PUF reliability and/or the number of response bits, they are rarely adopted in practice [28]. This is, in part, due to the fact that the reconfigurable logic may result in an increase in hardware resources overhead and operation complexity.…”

“…Moreover, as delay-based strong PUFs, they have been demonstrated to be vulnerable to modeling attacks, though many solutions to alleviate this issue have been proposed in recent years [6,18,24,29]. At this point, weak PUFs are more advantageous because it is more costly for an adversary to model them [28,30]. However, the size of their CRP space is very limited and an extra NVM is also required to store the secret keys generated.…”

A Lightweight and Machine-Learning-Resistant PUF Using Obfuscation-Feedback-Shift-Register

“…Physical Unclonable Function (PUF) [1] is an emerging hardware security primitive and provides a candidate solution for lightweight key generation and authentication. Due to uncontrolled and unpreditable process variations, each PUF instance generates a unique mapping relationship between the challenge and response.…”