结合区块链和群签名的车辆隐私匿名保护方案

Vehicle Privacy and Anonymity Protection Scheme Combining Blockchain and Group Signatures

车载自组织网络(VANETs)是移动网络在交通上的应用.而车辆身份隐私保护是VANETs安全中的重要组成部分.针对车辆隐私保护问题,本文提出了一种结合区块链和群签名的车辆隐私匿名保护方案(BGAS).在该方案中,当需要与数字证书认证机构(CA)进行通信时,车辆必须先进行群签名再与CA通信并将车辆的公钥存储于区块链中.若车辆提供虚假身份信息,群管理者会使用群私钥揭示签名者身份并授权CA撤销车辆公钥.在车辆与车辆之间发生通信前,车辆生成假名并用假名进行通信.通信过程中,车辆获取通信信息并请求CA解密假名并确认车辆身份.接收方需要用发送方的公钥进行哈希运算获得默克尔根植,用计算的根值与区块链中的根植通过匿名认证的方式比对,以此来确认车辆的合法性.

Vehicle Ad Hoc Networks(VANETs) are the applications of mobile networks in transportation.The privacy protection of vehicle identity is an important part of VANETs security.Aiming at the problem of vehicle privacy protection,this paper proposes a vehicle privacy anonymity protection scheme combining blockchain and group signatures(BGAS).In this solution,when vehicle needs to communicate with a digital certificate authority(CA),the vehicle first sign to the group before it can communicate with the CA and store the vehicle’s public key in the blockchain.In this process,if the vehicle provides false identity information,the group manager will use the group private key to reveal the signer’s identity and authorize the CA to revoke the vehicle public key.Before communication occurs between vehicle and vehicle,the vehicle generates a pseudonym and communicates with the pseudonym.During the communication process,the vehicle obtains the communication information and requests the CA to decrypt the pseudonym and confirm the vehicle identity.The receiver needs to use the sender’s public key to perform a hash operation to obtain Merkel roots,and use the calculated root value to compare with the roots in the blockchain through anonymous authentication to confirm the legitimacy of the vehicle.