Mini-MAC: Raising the bar for vehicular security with a lightweight message authentication protocol
Recent advances in in-vehicle technology have led to new systems being developed to control vehicles. The modern approach is to control the different systems within a vehicle using tens of electronic control units (ECUs). These ECUs are clustered into networks with gateways in between. A number of standards are used for communication within these standards and between them, but the most popular and the standard we will explore in this paper is the Controller Area Network (CAN) bus standard. Most of these networks, including CAN, were designed to prioritize reliability and safety over security. Security was not a large concern mainly because there was never any clear evidence whether the security of such a system could even be compromised. However, recent experiments have demonstrated practical attacks on some of the different systems within the car, including the ECUs controlling the engine, brakes, lighting, and climate control lighting. This means an adversary could take control of some of these systems and possibly harm the passengers inside the vehicle. Because of this, security is now a large concern for these networks and will become even greater as networked vehicles become more common. In this paper, we propose and implement a mixed public-key/shared-key authentication scheme for CAN and examine the advantages and disadvantages of implementing such a scheme.