Accountable Data Sharing Scheme Based On SGX And Blockchain

With the development of social information technology,data has become a key factor to promote development.It is becoming more and more important to use data sharing to explore the value behind data.The common data sharing model is that the data is provided by the data provider,the code is provided by the data demander,the code and data are calculated on a third-party platform.However,there are several problems in this model.First,once the third-party platform is attacked,the data and code will be tampered or stolen.Second,if the data is used illegally,it cannot be held accountable.To solve these problems,we propose an accountable data sharing scheme based on SGX and blockchain.SGX is used to ensure the confidentiality of shared data,and blockchain is used to record the user’s behavior information,so as to ensure that the records can not be tampered with and need not be maintained by a trusted third party.For the protection of data integrity and confidentiality,we propose a secure data sharing computing framework based on SGX.The scheme is based on the oblivious distributed computing framework(Obli DC)in the cloud environment,useing the DH key exchange and formal model of security processor to establish the identity authentication among data provider,data demander and server.We will give a detailed description of the scheme.Firstly,the security objectives of the scheme are defined,and the jobs in the distributed computing framework are modeled according to the directed job data flow graph.Then,the actual function and ideal function of the scheme are proposed,and it is proved that the ideal function can achieve the safety goal of the scheme.Finally,the security of the scheme is analyzed in the UC framework.The accountable decryption protocol is efficient and secure,but it only applies to single user and users are always online.Its log service uses the Merkle hash tree to record,exposing the privacy of users.In order to apply the protocol to the data sharing scenario,the following improvements are made in this paper: 1.Changing the protocol to multi-user and the user can be offline;2.For the data decryption and calculation in SGX,the secure computing framework proposed in Chapter 3 is added to the protocol;3.Using blockchain technology to achieve log services,while ensuring accountability,make the log records tamper proof and transparent,and solve the problem of user’s privacy exposure in the original protocol.Finally,an accountable data sharing scheme based on SGX and blockchain is proposed.In our paper,we will describe the scheme in detail,and compare it with the accountable decryption protocol in terms of function and security features,then the complexity analysis and security analysis of the scheme will be carried out.In the aspect of simulation test of the scheme,it is divided into three modules and designed.The basic process of the scheme is realized by using Golang.The simulation result shows that the code can basically realize the function of the scheme.