基于动态ID跳变的CAN总线安全调度算法

Security Scheduling Algorithm of CAN Bus Based on Dynamic ID Hopping

CAN(controller area network)总线是应用最广泛的现场总线,由于缺乏认证及消息检验机制,使得现在的CAN总线具有极大的安全隐患,需要为CAN总线设计防御机制.针对此情况,本文设计了一种优先级跳变机制,将通过散列函数进行一次性标识符动态跳变的方式引入到实时调度算法中.使用遗传算法计算固定优先级,求出优先级可妥协范围,将各帧进行分组,将数据帧的ID段进行分段重构,ID段前部分决定优先级并进行优先级跳变,ID段的后部分进行一次性动态跳变.实验结果表明,使用动态优先级和一次性ID跳变的方式进行跳变,相较于已有的ID跳变机制其安全性有了较大的提升.

CAN(controller area network)bus is the most widely used field bus.Due to the lack of authentication and message checking mechanism,CAN bus has great security risks,so it is necessary to design a defense mechanism for CAN bus.In this paper,a priority hopping mechanism is designed,which introduces the dynamic hopping of identifiers by Hash function into a real-time scheduling algorithm.The fixed priority is calculated by a genetic algorithm,and the compromise range of priority is found out.Each frame is grouped,and the ID segment of data frame is segmented and reconstructed.The former part of the ID segment determines the priority and performs priority hopping,while the latter part of the ID segment hops dynamically at one time.Experimental results show that using dynamic priority and one-time ID Hopping to hop has a greater security improvement than the existing ID Hopping mechanism.