Research On Secure Communication Of Vehicle CAN Bus Based On Encryption Algorithm

With the rapid development of intelligent vehicle,the vehicle is no longer a single means of transportation.The application of the Internet of Vehicles technologies such as auxiliary driving and V2 X,makes the vehicle a multifunctional integrated agent.The external network connects the vehicle with the surroundings through the interface,which can make it possible to interact with the In-vehicle equipment.However,it not only enriches the In-vehicle functions,but also brings the risk of attack.In-vehicle network is the foundation of automotive electronic systems,so the information security of In-vehicle bus networks has become a focus.Although the CAN protocol is a mainstream In-vehicle bus network and the information security issues was not considered at the beginning of design.A series of malicious attacks on the CAN bus such as stealing data,tampering with data,and replaying data,which poses a serious threat to the driver's personal and vehicles security.This dissertation analyzes the security vulnerabilities and security requirements of CAN bus networks,and design the communication method of security CAN bus with the aim of strengthening data confidentiality,message correctness and data freshness of CAN protocol.(1)In view of the fact that there is a lack of security protection mechanism in CAN protocol and the CAN messages are easy to be stolen,the AES encryption algorithm is used to encrypt the communication data on the CAN bus with the goal of ensuring data confidentiality.(2)In view of the Multi-Functional Mixed-Criticality Systems of the Automotive Electronic Systems,in order to meet the security requirements of different functions,ensure the real-time performance of the system and save resources,use encryption algorithms with different security levels fordifferent security-critical function messages,a Secure Communication of Vehicle CAN Bus Based on Encryption Algorithm is proposed.Designing the encryption algorithm level table,establishing the correspondence among functions,information security levels,and encryption algorithms,and using algorithm identification,dynamic scheduling of encryption algorithms has been implemented.Using synchronous counters to determine the logical relationship between the time sequence before and after receiving the message,adding a method to prevent replay attacks.Modifying the CAN frame format,taking the last byte of the CAN frame data field to store the synchronization counter and algorithm identification,improve the CAN security protocol.(3)CANoe is used to model the secure communication between ECUs and the dynamic encryption network.The secure communication protocol and the performance of secure communication is analyzed by experiments,and the effectiveness of the design is verified.