tornado-core/test/ERC20Mixer.test.js
2019-08-24 13:18:52 +03:00

196 lines
6.8 KiB
JavaScript

/* global artifacts, web3, contract */
require('chai')
.use(require('bn-chai')(web3.utils.BN))
.use(require('chai-as-promised'))
.should()
const fs = require('fs')
const { toBN, toHex, randomHex } = require('web3-utils')
const { takeSnapshot, revertSnapshot } = require('../lib/ganacheHelper')
const Mixer = artifacts.require('./ERC20Mixer.sol')
const Token = artifacts.require('./ERC20Mock.sol')
const { AMOUNT, MERKLE_TREE_HEIGHT, EMPTY_ELEMENT } = process.env
const websnarkUtils = require('websnark/src/utils')
const buildGroth16 = require('websnark/src/groth16')
const stringifyBigInts = require('websnark/tools/stringifybigint').stringifyBigInts
const unstringifyBigInts2 = require('snarkjs/src/stringifybigint').unstringifyBigInts
const snarkjs = require('snarkjs')
const bigInt = snarkjs.bigInt
const crypto = require('crypto')
const circomlib = require('circomlib')
const MerkleTree = require('../lib/MerkleTree')
const rbigint = (nbytes) => snarkjs.bigInt.leBuff2int(crypto.randomBytes(nbytes))
const pedersenHash = (data) => circomlib.babyJub.unpackPoint(circomlib.pedersenHash.hash(data))[0]
function generateDeposit() {
let deposit = {
secret: rbigint(31),
nullifier: rbigint(31),
}
const preimage = Buffer.concat([deposit.nullifier.leInt2Buff(31), deposit.secret.leInt2Buff(31)])
deposit.commitment = pedersenHash(preimage)
return deposit
}
// eslint-disable-next-line no-unused-vars
function BNArrayToStringArray(array) {
const arrayToPrint = []
array.forEach(item => {
arrayToPrint.push(item.toString())
})
return arrayToPrint
}
function getRandomReceiver() {
let receiver = rbigint(20)
while (toHex(receiver.toString()).length !== 42) {
receiver = rbigint(20)
}
return receiver
}
function snarkVerify(proof) {
proof = unstringifyBigInts2(websnarkUtils.fromSolidityInput(proof))
const verification_key = unstringifyBigInts2(require('../build/circuits/withdraw_verification_key.json'))
return snarkjs['groth'].isValid(verification_key, proof, proof.publicSignals)
}
contract('Mixer', accounts => {
let mixer
let token
const sender = accounts[0]
const operator = accounts[0]
const levels = MERKLE_TREE_HEIGHT || 16
const zeroValue = EMPTY_ELEMENT || 1337
const value = AMOUNT || '1000000000000000000' // 1 ether
let snapshotId
let prefix = 'test'
let tree
const fee = bigInt(AMOUNT).shr(1) || bigInt(1e17)
const receiver = getRandomReceiver()
const relayer = accounts[1]
let groth16
let circuit
let proving_key
before(async () => {
tree = new MerkleTree(
levels,
zeroValue,
null,
prefix,
)
mixer = await Mixer.deployed()
token = await Token.deployed()
await token.mint(sender, value)
snapshotId = await takeSnapshot()
groth16 = await buildGroth16()
circuit = require('../build/circuits/withdraw.json')
proving_key = fs.readFileSync('build/circuits/withdraw_proving_key.bin').buffer
})
describe('#constructor', () => {
it('should initialize', async () => {
const tokenFromContract = await mixer.token()
tokenFromContract.should.be.equal(token.address)
})
})
describe('#deposit', () => {
it('should work', async () => {
const commitment = 43
await token.approve(mixer.address, value)
let { logs } = await mixer.deposit(commitment, { from: sender })
logs[0].event.should.be.equal('Deposit')
logs[0].args.commitment.should.be.eq.BN(toBN(commitment))
logs[0].args.leafIndex.should.be.eq.BN(toBN(0))
})
})
describe('#withdraw', () => {
it('should work', async () => {
const deposit = generateDeposit()
const user = accounts[4]
await tree.insert(deposit.commitment)
await token.mint(user, value)
const balanceUserBefore = await token.balanceOf(user)
await token.approve(mixer.address, value, { from: user })
// Uncomment to measure gas usage
// let gas = await mixer.deposit.estimateGas(toBN(deposit.commitment.toString()), { value, from: user, gasPrice: '0' })
// console.log('deposit gas:', gas)
await mixer.deposit(toBN(deposit.commitment.toString()), { from: user, gasPrice: '0' })
const balanceUserAfter = await token.balanceOf(user)
balanceUserAfter.should.be.eq.BN(toBN(balanceUserBefore).sub(toBN(value)))
const { root, path_elements, path_index } = await tree.path(0)
// Circuit input
const input = stringifyBigInts({
// public
root,
nullifierHash: pedersenHash(deposit.nullifier.leInt2Buff(31)),
receiver,
fee,
// private
nullifier: deposit.nullifier,
secret: deposit.secret,
pathElements: path_elements,
pathIndex: path_index,
})
const proof = await websnarkUtils.genWitnessAndProve(groth16, input, circuit, proving_key)
const { pi_a, pi_b, pi_c, publicSignals } = websnarkUtils.toSolidityInput(proof)
const balanceMixerBefore = await token.balanceOf(mixer.address)
const balanceRelayerBefore = await token.balanceOf(relayer)
const balanceOperatorBefore = await token.balanceOf(operator)
const balanceRecieverBefore = await token.balanceOf(toHex(receiver.toString()))
let isSpent = await mixer.isSpent(input.nullifierHash.toString(16).padStart(66, '0x00000'))
isSpent.should.be.equal(false)
// Uncomment to measure gas usage
// gas = await mixer.withdraw.estimateGas(pi_a, pi_b, pi_c, publicSignals, { from: relayer, gasPrice: '0' })
// console.log('withdraw gas:', gas)
const { logs } = await mixer.withdraw(pi_a, pi_b, pi_c, publicSignals, { from: relayer, gasPrice: '0' })
const balanceMixerAfter = await token.balanceOf(mixer.address)
const balanceRelayerAfter = await token.balanceOf(relayer)
const balanceOperatorAfter = await token.balanceOf(operator)
const balanceRecieverAfter = await token.balanceOf(toHex(receiver.toString()))
const feeBN = toBN(fee.toString())
balanceMixerAfter.should.be.eq.BN(toBN(balanceMixerBefore).sub(toBN(value)))
balanceRelayerAfter.should.be.eq.BN(toBN(balanceRelayerBefore))
balanceOperatorAfter.should.be.eq.BN(toBN(balanceOperatorBefore).add(feeBN))
balanceRecieverAfter.should.be.eq.BN(toBN(balanceRecieverBefore).add(toBN(value)).sub(feeBN))
logs[0].event.should.be.equal('Withdraw')
logs[0].args.nullifierHash.should.be.eq.BN(toBN(input.nullifierHash.toString()))
logs[0].args.fee.should.be.eq.BN(feeBN)
isSpent = await mixer.isSpent(input.nullifierHash.toString(16).padStart(66, '0x00000'))
isSpent.should.be.equal(true)
})
})
afterEach(async () => {
await revertSnapshot(snapshotId.result)
// eslint-disable-next-line require-atomic-updates
snapshotId = await takeSnapshot()
tree = new MerkleTree(
levels,
zeroValue,
null,
prefix,
)
})
})