[論文レビュー] Security in Automotive Networks: Lightweight Authentication and Authorization

Philipp Mundhenk, Andrew Paverd+5 more|mediaTUM – the media and publications repository of the Technical University Munich (Technical University Munich)|Mar 10, 2017

Vehicular Ad Hoc Networks (VANETs)参考文献 30被引用数 59

ひとこと要約

The paper presents LASAN, a lightweight, formally verifiable authentication and authorization framework for in-vehicle networks that respects real-time constraints and life-cycle integration.

ABSTRACT

With the increasing amount of interconnections between vehicles, the attack surface of internal vehicle networks is rising steeply. Although these networks are shielded against external attacks, they often do not have any internal security to protect against malicious components or adversaries who breach the network perimeter. To secure the in-vehicle network, all communicating components must be authenticated, and only authorized components should be allowed to send and receive messages. This is achieved using an authentication framework. Cryptography is widely used to authenticate communicating parties and provide secure communication channels (e.g., Internet communication). However, the real-time performance requirements of in-vehicle networks restrict the types of cryptographic algorithms and protocols that may be used. In particular, asymmetric cryptography is computationally infeasible during vehicle operation. In this work, we address the challenges of designing authentication protocols for automotive systems. We present Lightweight Authentication for Secure Automotive Networks (LASAN), a full lifecycle authentication approach. We describe the core LASAN protocols and show how they protect the internal vehicle network while complying with the real-time constraints and low computational resources of this domain. Unlike previous work, we also explain how this framework can be integrated into all aspects of the automotive lifecycle, including manufacturing, vehicle maintenance, and software updates. We evaluate LASAN in two different ways: First, we analyze the security properties of the protocols using established protocol verification techniques based on formal methods. Second, we evaluate the timing requirements of LASAN and compare these to other frameworks using a new highly modular discrete event simulator for in-vehicle networks, which we have developed for this evaluation.

研究の動機と目的

• Address the rising internal attack surface in interconnected vehicles by securing in-vehicle communications.
• Develop a lightweight, real-time authentication and authorization protocol suitable for ECUs with limited resources.
• Integrate security protocols into the automotive product life cycle including manufacturing and updates.
• Provide formal security verification and performance evaluation to demonstrate practicality over existing schemes.

提案手法

• Introduce LASAN concepts and two-phase security design to separate symmetric (fast) and asymmetric (slow) operations.
• Define ECU authentication via PKINIT-based key exchange with a security module acting as a trusted authority.
• Detail stream authorization and centralized management of stream keys to enable multicast/broadcast security.
• Propose integration procedures for manufacturing, maintenance, and software updates within the automotive life cycle.
• Formally verify LASAN using the Scyther protocol analysis tool.
• Evaluate timing and bandwidth with a modular discrete-event simulator and compare against TLS and TESLA.

実験結果

リサーチクエスチョン

• RQ1 How can authentication and authorization be achieved in automotive networks while meeting real-time constraints and limited ECU resources?
• RQ2 Can a centralized security module enable scalable, multicast-secure communications without per-pair handshakes?
• RQ3 What is the formal security assurance of LASAN, and how does its performance compare to TLS and TESLA in in-vehicle networks?
• RQ4 How can LASAN be integrated across the automotive product life cycle, including manufacturing and updates?
• RQ5 What are the latency and bandwidth implications of LASAN under realistic in-vehicle conditions?

主な発見

• LASAN’s authentication and authorization protocols are verifiable for security using the Scyther formal verification tool.
• LASAN is evaluated for real-time performance with a new modular discrete-event simulator and compared to TLS and TESLA.
• The framework minimizes bandwidth and computation by exploiting fixed automotive network structure and multicast messaging.
• LASAN integrates security processes across the automotive life cycle, including secure exchange of ECUs and software updates.
• The design separates fast symmetric operations from slower asymmetric operations to preserve real-time communication constraints.