An E-Voting System Based on Tornado Cash

We propose an pseudo-anonymous e-voting platform based on the blockchain of Ethereum and a coin-mixer, that is Tornado Cash. After an online authentication and authorization phase, the user receives a fungible (i.e., pseudo-anonymous) voting token that can be deposited to a coin pool belonging to Tornado Cash (TC), together with an amount of Ether (ETH) A that will be used to pay successive fees. TC uses a smart contract that accepts token deposits that can be later withdrawn by a different address. In order to preserve privacy, a relayer contract can then be used to withdraw to a fresh ETH address (thus pseudo-anonymous) using A to pay fees. Relayers solve “fee payment dilemma”, that is paying withdrawal fees by maintaining pseudo-anonymity. Finally, a further smart contract collects preferences and, after the closure of the elections, it automatically performs the counting of votes. All the front-end has been developed in a Web browser, by using Javascript and avoiding the voter to perform any command-line operation to prepare transactions.