ECU Key Switching Using Synchronization Data for Secure Messaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The issue of in-vehicle network hacking poses a significant threat to the safety of automobile driving, as existing security measures for electronic control units rely on shared keys that can be compromised, leading to potential communication failures and safety risks.
Innovation Solution
A method for selecting and switching encryption keys based on synchronization information, such as freshness values or control information, within electronic control units to enhance message authentication and ensure secure communication without relying on dedicated synchronization signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a shared key is used for message authentication between electronic control units, then communication security is maintained, but the system becomes vulnerable to hacking and key compromise
Solution Approach 1:
The single shared key is segmented into multiple individual keys, each stored in separate memory locations. Each electronic control unit has its own unique key rather than sharing a common key, which prevents hacking vulnerability propagation. When a key is compromised, only that specific key needs to be updated rather than all shared keys in the system.
Solution Approach 2:
The key selection is made dynamic based on synchronization information such as message sequence numbers or timestamps. The transmitting unit selects a key based on current synchronization state, and the receiving unit independently selects the same key using its synchronized information, enabling adaptive key management without dedicated synchronization signals.
2Reliability
If dedicated synchronization signals are transmitted for key selection, then key synchronization between units is achieved, but communication efficiency decreases due to additional signal overhead
Solution Approach 1:
The key selection synchronization is merged with the existing message authentication process. The synchronization information is embedded within or derived from the message data itself rather than being transmitted as a separate dedicated signal. This combines multiple functions into a single communication flow, eliminating overhead.
Solution Approach 2:
Each electronic control unit independently selects the key using its own synchronization information (such as local sequence counters or timestamps) without requiring external synchronization signals from other units. The system self-synchronizes through autonomous key selection based on locally maintained state.
3Reliability
If multiple keys are stored in memory for selection, then authentication security is enhanced, but memory requirements and device complexity increase
Solution Approach 1:
Different keys are stored in different, specifically designated memory locations with unique addresses. Each key has its own storage location optimized for its specific authentication purpose. This organized local storage allows efficient key retrieval without requiring complex memory management, as each key's position and selection criteria are predetermined.
Data Source
AI summary
A communication system includes a transmission-side electronic control unit and a reception-side electronic control unit. In the transmission-side electronic control unit, one key is selected from a plurality of keys in a memory based on synchronization information which is information synchronized in communication between the transmission-side electronic control unit and the reception-side electronic control unit. Further, a message is generated and a message authentication code (MAC) is generated using the selected key. The message to which the message authentication code is added is transmitted to the reception-side electronic control unit.