VANET中隐私保护的格基异构签密方案

Lattice-based Heterogeneous Signcryption Scheme for VANET Privacy Preservation

针对车载自组织网络(Vehicular Ad hoc Network,VANET)中车辆跨密码系统通信过程中的隐私泄露问题,提出了一种格基异构签密方案.首先,方案实现了无证书密码系统(Certificateless Cryptosystem,CLC)的车辆与基于身份密码系统(Identity-Based Cryptosystem,IBC)的车辆相互通信;其次利用签密的机密性和可认证性防止车辆用户在跨密码系统通信过程中发生隐私泄露,并实现了接收方对消息完整性以及发送方身份合法性的认证;最后在随机预言机模型下证明了方案在适应性选择密文攻击下具有不可区分性(Indistinguishability against adaptive Chosen Cipher Text Attack,IND-CCA2),在适应性选择消息攻击下具有存在性不可伪造性(Existential Unforgeability against adaptive Chosen Messages Attack,EUF-CMA).性能分析表明,与其他方案相比,本文方案在计算开销、通信开销和安全性方面具有一定优势,适用于车辆跨密码系统通信的场景.

To address the privacy leakage during cross-cryptosystem communication of vehicles in Vehicular Ad hoc Network(VANET),a lattice based heterogeneous signcryption scheme is proposed.Firstly,the proposed scheme realizes the communication between vehicles based on Certificateless Cryptosystem(CLC)and vehicles based on Identity-Based Cryptosystem(IBC).Secondly,the confidentiality and authenticity of the signcryption prevent the users from privacy leakage during the cross-cryptosystem communication,and achieve the authentication of the message integrity and the sender′s identity legitimacy.Finally,the proposed scheme is proved to have Indistinguishability under Chosen Ciphertext Attack(IND-CCA2)and Existential Unforgeability against adaptive Chosen Messages Attack(EUF-CMA)under the random oracle model.Performance analysis shows that compared to other schemes,the proposed scheme has higher performance in terms of computational overhead,communication overhead,and security,and is suitable for scenarios where vehicles communicate across cryptosystem.