$L^{2}S^{2}C^{2}$: Lattice-based Lightweight Scheme for Secure Communication in Controller Area Networks

The Controller Area Network (CAN) is a standard bus-based communication protocol for reliable Cyber-Physical Systems. For instance, in cars, around 100 Electronic Control Units (ECUs) are connected via CAN. Recent news proves that attackers can easily connect external devices to the CAN bus and gain control over ECUs communications, have access to the car, and possibly steal it. Despite the existing literature on authentication protocols designed for CAN buses, no existing work currently tackles the further threat imposed by the growing interest and developments of quantum computing. In this paper, we propose <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$L^{2}S^{2}C^{2}$</tex>, a novel post-quantum authentication protocol that leverages Physically Unclonable Functions (PUF) and Lattice-based Cryptography (LBC). The usage of PUF in <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$L^{2}S^{2}C^{2}$</tex> ensures low storage cost, while the lattice-based formulation ensures resistance to quantum attacks. _ <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\lrcorner \mathrm{r}^{2}S^{2}C^{2}$</tex> is resistant to different types of attacks such as replay, false message injection, plain text, collision, ML attacks, man-in-the-middle, impersonation, sybil, denial-of-service, and bus-off, other than quantum attacks. The performance analysis results reveal that <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$L^{2}S^{2}C^{2}$</tex> ensures improved security and reliability than the state-of-the-art.