A Format-Verifiable E-Voting Scheme Using Homomorphic Encryption

Electronic-voting (e-voting) is taking place of the traditional paper voting, due to its efficiency and environmental protection. To protect the privacy of the votes, voters usually blind or encrypt the votes before submitting them. But the blinded or encrypted votes also hide the format of them and the receiver cannot distinguish if they are legal or not in format. To solve such a problem, this paper proposes a privacy-preserving e-voting scheme, that can validate the correctness of the cast ballots in format. Two protocols are designed based on homomorphic encryption to verify the format of the votes, without disclosing the content, and the designated verifier signature is adopted to obtain the receipt-freeness. The analysis shows the provable security of the protocols, and the proposed e-voting scheme achieves the format verifiability, in addition to meeting the requirements of other aspects in security.