PUF-PassSE: A PUF based Password Strength Enhancer for IoT Applications

Authentications and encryptions are urgently needed by the growing number of hardware devices for security applications of the Internet of Things (IoT). However, the existing cryptographic solutions may not be applicable to IoT devices because of the strict timing and power requirements of the devices. As a result, Physical Unclonable Function (PUF) is a promising hardware primitive to provide security in existing and future IoT applications due to it is lower hardware cost and energy efficient. In this paper, we propose an innovated application of PUF as an entropy pump to improve the entropy. Furthermore, we apply the PUF-based entropy pump in a password enhancement application for embedded IoT devices. We confirmed that an overall 48% significant improvement on the entropy of the human-generated passwords. The proposed design is demonstrated on the Nexys 4 DDR FPGA board with low hardware overhead, which ensures the feasibility for IoT applications.