chepaillier-voting

A simple implementation of a voting system which preserve voters anonimity using homomorphic encryption (based on Paillier cryptosystem).

Brief

Using homomorphic encryption we can create an encryption of a number using a public key, add encrypted numbers and get an encrypted result of the sum (that we can decrypt with a private key).

We can use this property to record voting preferences without exposing the selected votes.

Usage

const { mkBallot, vote, tally, decryptTally } = require('chepaillier-voting')

const [privateKey, ballot] = mkBallot('Where is the love?', ['Tokyo', 'London', 'Paris', 'Berlin'])
// Publish your ballot
// Protect your private key!

const nextBallot1 = vote(ballot, 'user-14341', 'Tokyo', 3)
const nextBallot2 = vote(ballot, 'user-42345', 'London', 1)
// Record votes
// You can update votes multiple times for the same user

const encryptedTally = tally(nextBallot2)
const result = decryptTally(privateKey, encryptedTally)
// {
//   Tokyo: 3,
//   London: 1,
//   Paris: 0,
//   Berlin: 0
// }

TODO

Add zero knowledge proof that the casted vote is one of N values.

Tests

Tests live in the index file in the shape of a bunch of asserts.

Tests get removed automatically at postinstall using sed.

License

MIT