Unified Lightweight Authenticated Encryption for Resource-Constrained Electronic Control Unit

Electronic control units (ECU) have been widely used in modern resource-constrained automotive systems, com-municating through the controller area network (CAN) bus. However, they are still facing man-in-the-middle attacks in CAN bus due to the absence of a more effective authenti-cation/encryption mechanism. In this paper, to defend against the attacks more effectively, we propose a unified lightweight authenticated encryption that integrates recent prevalent cryp-tography standardization Isap and Ascon.First, we reuse the common permutation block of ISAP and Asconto support authenticated encryption and encryption/decryption. Second, we provide a flexible and independent switch between authenticated encryption and encryption/decryption to support specific application requirements. Third, we adopt standard CAESAR hardware API as the interface standard to support compatibility between different interfaces or platforms. Experimental results show that our proposed unified lightweight authenticated encryption can reduce 26.09% area consumption on Xilinx Artix-7 FPGA board compared with the state-of-the-arts. In addition, the encryption overhead of the proposed design for transferring one CAN data frame is
$\mathbf{10.75} \mu s$
using Asconand
$\mathbf{72.25} \mu s$
using ISAP at the frequency of 4 MHz on embedded devices.