Hääl

Anonymous Electronic Voting System on Public Blockchains

Hääl means voice in Estonian. Voice means power of people.

This code is a proof-of-concept of the protocol presented on the whitepaper located at the root folder. It describes a full process for an e-voting system, using public blockchains and without a mixnet or an oracle for tallying the votes.

The full protocol makes use of:

• Zero-knowledge proofs (with zk-snarks verified on-chain)
• Homomorphic encryption (Paillier protocol + zk)
• Stealth addresses (as proposed by Peter Todd, but ported to ethereum)
• Encrypted notes (e.g Zcash, AZTEC)
• Cryptography challenges (based on Sigma protocol)
• Digital signatures
• Ethereum (or another blockchain capable of running dApps)
• other technologies described on the whitepaper

Working in progress. All contributions are welcome.

Pre-requisites

• ganache-cli ^6.3.0 or Ganache ^1.2.2
• Node ^8
• Solidity ^0.4.5
• Yarn ^1.13.0

Setup

# yarn install && yarn truffle build && yarn ganache-cli

Run

(on a new terminal)
# yarn truffle test

---

optionally, you can build and run with npm and node

# npm install -Wno-cast-function-type 2> debug.log
# node ./node_modules/truffle/build/cli.bundled.js build
Run ganache (or ganache-cli)
# node ./node_modules/truffle/build/cli.bundled.js test

Compile warnings

Is expected to receive the warning below during contracts compilation:

haal/contracts/HAAL/haal.sol:2:1: Warning: Experimental features are turned on. Do not use experimental features on live deployments.
pragma experimental ABIEncoderV2;
^-------------------------------^

That message appears because we're using an experimental method to fill arrays (bytes[]):

function addVote(
        bytes[] _president, 
        bytes[] _senator, 
        bytes[] _stateGovernor,
        ^-----^
[...]

and

function getVotes(uint _index) view public returns(bytes[], bytes[], bytes[])
                                                   ^-----------------------^

Apache License