Vehicle-to-infrastructure (V2I) communication is the basis for vehicles to obtain information about the road ahead. The confidentiality and reliability of V2I communication guarantee traffic safety and smooth flow. Authenticated key agreement (AKA) is the most commonly used technique to establish secure communication channels. Signature-based AKA inevitably exposes the identity information of vehicles, while Encryption-based AKA can bring deniability and high privacy, which means no adversary can know who sent the AKA message. Certificateless encryption (CLE) can simultaneously solve burdensome certificate management and key escrow. However, existing certificateless cryptography requires two loosely combined public keys to represent a device and does not consider the physical security of storing secret keys locally. This paper first designed an improved CLE scheme with one-device-one-public-key, and performance comparisons show that the proposed CLE has optimal storage and computation performance. Considering that rare work was put on encryption-based AKA, this paper proposed a deniable and privacy-preserving certificateless AKA for V2I communication by incorporating Physically Unclonable Function (PUF)-secured key management to prevent physical leakage of keys, named CLE-AKA-PUF. Feature comparison illustrates that CLE-AKA-PUF supports key escrow-free, dual authentication, physical security, deniability, and high privacy. Security proofs and performance analysis demonstrate the practicability and efficiency of CLE-AKA-PUF.

中文翻译：

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基于 CLE 的身份验证密钥协议，具有用于车辆到基础设施的 PUF 安全密钥

车辆到基础设施 （V2I） 通信是车辆获取有关前方道路信息的基础。V2I 通信的机密性和可靠性保证了交通安全和顺畅。经过身份验证的密钥协议 （AKA） 是建立安全通信通道的最常用技术。基于签名的 AKA 不可避免地暴露了车辆的身份信息，而基于加密的 AKA 可以带来可否认性和高度隐私性，这意味着没有对手可以知道谁发送了 AKA 消息。无证书加密 （CLE） 可以同时解决繁琐的证书管理和密钥托管问题。但是，现有的无证书加密需要两个松散组合的公钥来表示一个设备，并且不考虑在本地存储密钥的物理安全性。该文首先设计了一种改进的一设备一公钥的 CLE 方案，性能对比表明，所提出的 CLE 具有最优的存储和计算性能。考虑到基于加密的 AKA 工作很少见，本文提出了一种可否认且隐私保护的无证书 AKA，用于 V2I 通信，通过结合物理不可克隆功能 （PUF） 安全的密钥管理来防止密钥的物理泄漏，命名为 CLE-AKA-PUF。功能对比表明，CLE-AKA-PUF 支持密钥免托管、双重认证、物理安全、可否认性和高隐私性。安全证明和性能分析证明了 CLE-AKA-POF 的实用性和有效性。