Enhanced Message Authentication Code for Controller Area Network

An automobile is an electronic gadget on wheels with the help of electronic control unit (ECU), sensors, and actuators. These integrated electronics are required in-vehicle communications protocols to communicate with each other for data exchange. The protocols like controller area network (CAN), local interconnect network (LIN), FlexRay, and others are used. CAN is the most widely used protocol because of its robust and reliable behavior with a data rate of 1 Mb/s. Apart from merits, the CAN bus includes a few security issues that are the major sources for the attackers to take control of the CAN bus including unauthorized CAN nodes in the network. In this paper, we proposed an enhanced message authentication code (MAC) generation to ensure the authenticity and integrity of the CAN data. We solved the payload limitation of the CAN by making the truncated MAC of 1 byte from the 8 bytes. In addition, we performed reverse engineering to ensure the generated truncated MAC is 1 byte and the same at the receiver and sender end, tested the open-source CAN data of the Nissan vehicle and explained the future work of the proposed method.