Design Of Electronic Voting Scheme Based On Blockchain

With the continuous advancement of society and the continuous improvement of people's quality,people hope to express their ideas in social life.Voting is a way of making collective decisions.It is an important tool for democracy.However,most current electronic voting schemes are based on trusted third parties.Voters must trust trusted third parties.Trusted third parties complete work such as voter registration,voter information and ballot storage,counting and final results,verification of final results and so on.Due to the excessive power of trusted third parties,the correctness and fairness of the final election results were questioned.The blockchain is essentially a distributed database with decentralization,de-trusting,transparent data,and non-tamperability,Combined with electronic voting,it can effectively solve many problems in electronic voting.Aiming at the security problems existing in the electronic voting scheme,this paper focuses on small and medium-sized voting scenarios.It studies the technologies of blockchain,associated ring signature,secret sharing,El Gamal cryptosystem,and smart contract.The main work is as follows:(1)In view of the problem that the correctness and fairness of the final election results are questioned due to the excessive power of trusted third parties in the current electronic voting scheme,this paper adopts blockchain technology to ensure the transparency and credibility of voting data.The technology of ring signature is used to complete the secret identity of voters.Combined with the idea of secret sharing and distributed ELGamal encryption,a threshold encryption scheme based on Lagrangian interpolation formula is designed to ensure the encryption of votes without relying on trusted third parties.The smart contract is used to complete all kinds of operations in the voting process,which ensures the security and decentralization of the voting scheme.Finally,by analyzing the security of the proposed electronic voting scheme,it is shown that the proposed scheme can meet the basic security requirements of electronic voting.(2)In this thesis,a smart contract is written to implement the proposed electronic voting scheme,and a separate program is written for the voter to generate encrypted ballot and sign the associated ring.The contract of this scheme is divided into four parts: the secp256k1.sol contract realizes the basic operation of the secure elliptic curve and elliptic curve selected in this scheme.The Threshold Crpto.sol contract completes the calculation of the threshold public-private key pair and the decryption of the ballot paper.The Linkable Ring Signature.sol contract verifies the signature of the associated ring.The Vote.sol contract completes the voting process by interacting with the other three contracts.In addition,two programs have been designed for voters to encrypt and sign their ballots before voting.(3)The Ganache tool was used to build the Ethereum private blockchain to test the key methods of the electronic voting scheme proposed in this paper.The Gas consumption and time consumption of the key method are recorded.In addition,the procedure for the voter to generate the associated ring signature was tested and analyzed.Through the analysis of the experimental results,it is shown that the scheme proposed in this paper can meet the expectation.