区块链与环签密结合的电子证据认证加密方案

Authenticated encryption scheme of electronic evidence based on blockchain and ring signcryption

由于电子证据存在易篡改、易伪造等问题,电子证据的真实性判定成为证据法理论中的难点之一。针对这一难点问题,基于区块链技术构建一个电子证据分布式存储方案解决传统中心化存储所面临的非法删除与篡改等问题,从而实现电子证据的分布式信任机制。此外,为了防止电子证据在链上共享时泄露给非授权用户,需要对其进行加密操作,同时为了防止证据采集者上传错误数据,需要对其进行认证操作。针对电子证据的保密性与不可否认性需求,提出一个新的多中心环签密方案,对电子证据进行匿名认证与加密操作,防止签名者身份信息泄露及证据数据被非授权用户获取。对比分析表明,所提方案适用于电子证据存储认证区块链系统,且比同类型环签密方案具有更高的安全性。

Electronic evidence is easy to tamper or forge.Therefore,authenticity judgment of electronic evidence has become a difficult point in the theory of evidence law.To solve this problem,a storage scheme of electronic evidence is constructed based on blockchain technology which can prevent the problems of illegal deletion and tampering in the setting of centralized storage.Hence,it can realize the distributed trust mechanism.In addition,electronic evidence needs to be encrypted to prevent unauthorized user from obtaining the data,and it also needs to be authenticated to prevent evidence collector to publish error data.This work gives a new multi-authority ring signcryption scheme which can execute anonymous authentication and encryption for electronic evidence.The proposed scheme can prevent the disclosure of signer's identity information and acquisition of evidence data by unauthorized user.Through analysis,it is shown that the proposed scheme is suitable for the blockchain system of storage and authentication of electronic evidence,and it has higher security than the other ring signcryption schemes.