基于可搜索加密的区块链数据隐私保护机制

Blockchain data privacy protection mechanism based on searchable encryption

针对存储在区块链的交易数据都是公开透明的,账户隐私和交易信息得不到保护的问题,提出一种基于可搜索加密的区块链数据隐私保护机制的方法。首先,使用区块链来存储重要数据,存储的是数据的加密形式,可以有效防止明文数据的泄露;其次,为了提供加密数据的搜索功能,利用双线性映射的数学特性来构造区块链交易单,在交易单中增加对关键词的加密信息用于关键词搜索;最后,由用户使用可搜索加密私钥构造陷门,来进行指定关键词搜索。将该机制运用于个人医疗数据区块链系统,解决了个人医疗隐私信息的泄露等问题,搜索时间为2400个关键词用时为11.23 s。运用该机制不仅增强了区块链数据隐私保护能力,也提供了加密隐私数据的查找和实用的便利。

Aiming at the problem that the data stored in the blockchain are open and the account privacy cannot be protected,a method based on the searchable encryption of the blockchain data privacy protection mechanism was proposed.Firstly,when using blockchain to store important data,the encrypted form of data were stored,which can effectively prevent the disclosure of plaintext data.Secondly,in order to provide the search function of encrypted data,the mathematical feature of bilinear mapping was used to construct the block chain transaction sheet,and the encrypted information of keywords in the transaction sheet was added for keyword search.Finally,a trap door was constructed by the user using the searchable encrypted private key to perform the specified keyword search.The mechanism was applied to the blockchain system of personal medical data,which solved the leakage of personal medical privacy information and other problems.The search took 11.23 s for 2400 keywords.The use of this mechanism not only enhances the blockchain data privacy protection capabilities,but also provides the search for encrypted privacy data and practical convenience.