tornado-core/cli.js
2019-11-10 03:48:09 +03:00

466 lines
16 KiB
JavaScript
Executable File

#!/usr/bin/env node
// Temporary demo client
// Works both in browser and node.js
const fs = require('fs')
const axios = require('axios')
const assert = require('assert')
const snarkjs = require('snarkjs')
const crypto = require('crypto')
const circomlib = require('circomlib')
const bigInt = snarkjs.bigInt
const merkleTree = require('./lib/MerkleTree')
const Web3 = require('web3')
const buildGroth16 = require('websnark/src/groth16')
const websnarkUtils = require('websnark/src/utils')
const { toWei, fromWei } = require('web3-utils')
let web3, mixer, erc20mixer, circuit, proving_key, groth16, erc20, senderAccount
let MERKLE_TREE_HEIGHT, ETH_AMOUNT, TOKEN_AMOUNT, ERC20_TOKEN
/** Whether we are in a browser or node.js */
const inBrowser = (typeof window !== 'undefined')
/** Generate random number of specified byte length */
const rbigint = nbytes => snarkjs.bigInt.leBuff2int(crypto.randomBytes(nbytes))
/** Compute pedersen hash */
const pedersenHash = data => circomlib.babyJub.unpackPoint(circomlib.pedersenHash.hash(data))[0]
/** BigNumber to hex string of specified length */
function toHex(number, length = 32) {
let str = number instanceof Buffer ? number.toString('hex') : bigInt(number).toString(16)
return '0x' + str.padStart(length * 2, '0')
}
/** Display account balance */
async function printBalance(account, name) {
console.log(`${name} ETH balance is`, web3.utils.fromWei(await web3.eth.getBalance(account)))
console.log(`${name} Token Balance is`, web3.utils.fromWei(await erc20.methods.balanceOf(account).call()))
}
/**
* Create deposit object from secret and nullifier
*/
function createDeposit(nullifier, secret) {
let deposit = { nullifier, secret }
deposit.preimage = Buffer.concat([deposit.nullifier.leInt2Buff(31), deposit.secret.leInt2Buff(31)])
deposit.commitment = pedersenHash(deposit.preimage)
deposit.nullifierHash = pedersenHash(deposit.nullifier.leInt2Buff(31))
return deposit
}
/**
* Make an ETH deposit
*/
async function deposit() {
const deposit = createDeposit(rbigint(31), rbigint(31))
console.log('Submitting deposit transaction')
await mixer.methods.deposit(toHex(deposit.commitment)).send({ value: ETH_AMOUNT, from: senderAccount, gas:1e6 })
const note = toHex(deposit.preimage, 62)
console.log('Your note:', note)
return note
}
/**
* Make an ERC20 deposit
*/
async function depositErc20() {
const deposit = createDeposit(rbigint(31), rbigint(31))
if(ERC20_TOKEN === '') {
console.log('Minting some test tokens to deposit')
await erc20.methods.mint(senderAccount, TOKEN_AMOUNT).send({ from: senderAccount, gas: 1e6 })
}
console.log('Approving tokens for deposit')
await erc20.methods.approve(erc20mixer._address, TOKEN_AMOUNT).send({ from: senderAccount, gas:1e6 })
console.log('Submitting deposit transaction')
await erc20mixer.methods.deposit(toHex(deposit.commitment)).send({ from: senderAccount, gas:1e6 })
const note = toHex(deposit.preimage, 62)
console.log('Your note:', note)
return note
}
/**
* Generate merkle tree for a deposit.
* Download deposit events from the contract, reconstructs merkle tree, finds our deposit leaf
* in it and generates merkle proof
* @param contract Mixer contract address
* @param deposit Deposit object
*/
async function generateMerkleProof(contract, deposit) {
// Get all deposit events from smart contract and assemble merkle tree from them
console.log('Getting current state from mixer contract')
const events = await contract.getPastEvents('Deposit', { fromBlock: contract.deployedBlock, toBlock: 'latest' })
const leaves = events
.sort((a, b) => a.returnValues.leafIndex - b.returnValues.leafIndex) // Sort events in chronological order
.map(e => e.returnValues.commitment)
const tree = new merkleTree(MERKLE_TREE_HEIGHT, leaves)
// Find current commitment in the tree
let depositEvent = events.find(e => e.returnValues.commitment === toHex(deposit.commitment))
let leafIndex = depositEvent ? depositEvent.returnValues.leafIndex : -1
// Validate that our data is correct
const isValidRoot = await contract.methods.isKnownRoot(toHex(await tree.root())).call()
const isSpent = await contract.methods.isSpent(toHex(deposit.nullifierHash)).call()
assert(isValidRoot === true, 'Merkle tree is corrupted')
assert(isSpent === false, 'The note is already spent')
assert(leafIndex >= 0, 'The deposit is not found in the tree')
// Compute merkle proof of our commitment
return await tree.path(leafIndex)
}
/**
* Generate SNARK proof for withdrawal
* @param contract Mixer contract address
* @param note Note string
* @param recipient Funds recipient
* @param relayer Relayer address
* @param fee Relayer fee
* @param refund Receive ether for exchanged tokens
*/
async function generateProof(contract, note, recipient, relayer = 0, fee = 0, refund = 0) {
// Decode hex string and restore the deposit object
let buf = Buffer.from(note.slice(2), 'hex')
let deposit = createDeposit(bigInt.leBuff2int(buf.slice(0, 31)), bigInt.leBuff2int(buf.slice(31, 62)))
// Compute merkle proof of our commitment
const { root, path_elements, path_index } = await generateMerkleProof(contract, deposit)
// Prepare circuit input
const input = {
// Public snark inputs
root: root,
nullifierHash: deposit.nullifierHash,
recipient: bigInt(recipient),
relayer: bigInt(relayer),
fee: bigInt(fee),
refund: bigInt(refund),
// Private snark inputs
nullifier: deposit.nullifier,
secret: deposit.secret,
pathElements: path_elements,
pathIndices: path_index,
}
console.log('Generating SNARK proof')
console.time('Proof time')
const proofData = await websnarkUtils.genWitnessAndProve(groth16, input, circuit, proving_key)
const { proof } = websnarkUtils.toSolidityInput(proofData)
console.timeEnd('Proof time')
const args = [
toHex(input.root),
toHex(input.nullifierHash),
toHex(input.recipient, 20),
toHex(input.relayer, 20),
toHex(input.fee),
toHex(input.refund)
]
return { proof, args }
}
/**
* Do an ETH withdrawal
* @param note Note to withdraw
* @param recipient Recipient address
*/
async function withdraw(note, recipient) {
const { proof, args } = await generateProof(mixer, note, recipient)
console.log('Submitting withdraw transaction')
await mixer.methods.withdraw(proof, ...args).send({ from: senderAccount, gas: 1e6 })
console.log('Done')
}
/**
* Do a ERC20 withdrawal
* @param note Note to withdraw
* @param recipient Recipient address
*/
async function withdrawErc20(note, recipient) {
const { proof, args } = await generateProof(erc20mixer, note, recipient)
console.log('Submitting withdraw transaction')
await erc20mixer.methods.withdraw(proof, ...args).send({ from: senderAccount, gas: 1e6 })
console.log('Done')
}
/**
* Do an ETH withdrawal through relay
* @param note Note to withdraw
* @param recipient Recipient address
* @param relayUrl Relay url address
*/
async function withdrawRelay(note, recipient, relayUrl) {
const resp = await axios.get(relayUrl + '/status')
const { relayerAddress, netId, gasPrices } = resp.data
assert(netId === await web3.eth.net.getId() || netId === '*', 'This relay is for different network')
console.log('Relay address: ', relayerAddress)
const fee = bigInt(toWei(gasPrices.fast.toString(), 'gwei')).mul(bigInt(1e6))
const { proof, args } = await generateProof(mixer, note, recipient, relayerAddress, fee)
console.log('Sending withdraw transaction through relay')
const resp2 = await axios.post(relayUrl + '/relay', { contract: mixer._address, proof: { proof, publicSignals: args } })
console.log(`Transaction submitted through relay, tx hash: ${resp2.data.txHash}`)
let receipt = await waitForTxReceipt(resp2.data.txHash)
console.log('Transaction mined in block', receipt.blockNumber)
console.log('Done')
}
/**
* Do a ERC20 withdrawal through relay
* @param note Note to withdraw
* @param recipient Recipient address
* @param relayUrl Relay url address
*/
async function withdrawRelayErc20(note, recipient, relayUrl) {
const resp = await axios.get(relayUrl + '/status')
const { relayerAddress, netId, gasPrices, ethPriceInDai } = resp.data
assert(netId === await web3.eth.net.getId() || netId === '*', 'This relay is for different network')
console.log('Relay address: ', relayerAddress)
const refund = bigInt(toWei('0.001'))
const fee = bigInt(toWei(gasPrices.fast.toString(), 'gwei')).mul(bigInt(1e6)).add(refund).mul(bigInt(fromWei(ethPriceInDai.toString())))
const { proof, args } = await generateProof(erc20mixer, note, recipient, relayerAddress, fee, refund)
console.log('Sending withdraw transaction through relay')
const resp2 = await axios.post(relayUrl + '/relay', { contract: erc20mixer._address, proof: { proof, publicSignals: args } })
console.log(`Transaction submitted through relay, tx hash: ${resp2.data.txHash}`)
let receipt = await waitForTxReceipt(resp2.data.txHash)
console.log('Transaction mined in block', receipt.blockNumber)
console.log('Done')
}
/**
* Waits for transaction to be mined
* @param txHash Hash of transaction
* @param attempts
* @param delay
*/
function waitForTxReceipt(txHash, attempts = 60, delay = 1000) {
return new Promise((resolve, reject) => {
const checkForTx = async (txHash, retryAttempt = 0) => {
const result = await web3.eth.getTransactionReceipt(txHash)
if (!result || !result.blockNumber) {
if (retryAttempt <= attempts) {
setTimeout(() => checkForTx(txHash, retryAttempt + 1), delay)
} else {
reject(new Error('tx was not mined'))
}
} else {
resolve(result)
}
}
checkForTx(txHash)
})
}
/**
* Init web3, contracts, and snark
*/
async function init() {
let contractJson, erc20ContractJson, erc20mixerJson
if (inBrowser) {
// Initialize using injected web3 (Metamask)
// To assemble web version run `npm run browserify`
web3 = new Web3(window.web3.currentProvider, null, { transactionConfirmationBlocks: 1 })
contractJson = await (await fetch('build/contracts/ETHMixer.json')).json()
circuit = await (await fetch('build/circuits/withdraw.json')).json()
proving_key = await (await fetch('build/circuits/withdraw_proving_key.bin')).arrayBuffer()
MERKLE_TREE_HEIGHT = 16
ETH_AMOUNT = 1e18
TOKEN_AMOUNT = 1e19
} else {
// Initialize from local node
web3 = new Web3('http://localhost:8545', null, { transactionConfirmationBlocks: 1 })
contractJson = require('./build/contracts/ETHMixer.json')
circuit = require('./build/circuits/withdraw.json')
proving_key = fs.readFileSync('build/circuits/withdraw_proving_key.bin').buffer
require('dotenv').config()
MERKLE_TREE_HEIGHT = process.env.MERKLE_TREE_HEIGHT
ETH_AMOUNT = process.env.ETH_AMOUNT
TOKEN_AMOUNT = process.env.TOKEN_AMOUNT
ERC20_TOKEN = process.env.ERC20_TOKEN
erc20ContractJson = require('./build/contracts/ERC20Mock.json')
erc20mixerJson = require('./build/contracts/ERC20Mixer.json')
}
groth16 = await buildGroth16()
let netId = await web3.eth.net.getId()
if (contractJson.networks[netId]) {
const tx = await web3.eth.getTransaction(contractJson.networks[netId].transactionHash)
mixer = new web3.eth.Contract(contractJson.abi, contractJson.networks[netId].address)
mixer.deployedBlock = tx.blockNumber
}
const tx3 = await web3.eth.getTransaction(erc20mixerJson.networks[netId].transactionHash)
erc20mixer = new web3.eth.Contract(erc20mixerJson.abi, erc20mixerJson.networks[netId].address)
erc20mixer.deployedBlock = tx3.blockNumber
if(ERC20_TOKEN === '') {
erc20 = new web3.eth.Contract(erc20ContractJson.abi, erc20ContractJson.networks[netId].address)
const tx2 = await web3.eth.getTransaction(erc20ContractJson.networks[netId].transactionHash)
erc20.deployedBlock = tx2.blockNumber
}
senderAccount = (await web3.eth.getAccounts())[0]
console.log('Loaded')
}
// ========== CLI related stuff below ==============
/** Print command line help */
function printHelp(code = 0) {
console.log(`Usage:
Submit a deposit from default eth account and return the resulting note
$ ./cli.js deposit
$ ./cli.js depositErc20
Withdraw a note to 'recipient' account
$ ./cli.js withdraw <note> <recipient> [relayUrl]
$ ./cli.js withdrawErc20 <note> <recipient> [relayUrl]
Check address balance
$ ./cli.js balance <address>
Perform an automated test
$ ./cli.js test
$ ./cli.js testRelay
Example:
$ ./cli.js deposit
...
Your note: 0x1941fa999e2b4bfeec3ce53c2440c3bc991b1b84c9bb650ea19f8331baf621001e696487e2a2ee54541fa12f49498d71e24d00b1731a8ccd4f5f5126f3d9f400
$ ./cli.js withdraw 0x1941fa999e2b4bfeec3ce53c2440c3bc991b1b84c9bb650ea19f8331baf621001e696487e2a2ee54541fa12f49498d71e24d00b1731a8ccd4f5f5126f3d9f400 0xee6249BA80596A4890D1BD84dbf5E4322eA4E7f0
`)
process.exit(code)
}
/** Process command line args and run */
async function runConsole(args) {
if (args.length === 0) {
printHelp()
} else {
switch (args[0]) {
case 'deposit':
if (args.length === 1) {
await init()
await printBalance(mixer._address, 'Mixer')
await printBalance(senderAccount, 'Sender account')
await deposit()
await printBalance(mixer._address, 'Mixer')
await printBalance(senderAccount, 'Sender account')
} else {
printHelp(1)
}
break
case 'depositErc20':
if (args.length === 1) {
await init()
await printBalance(erc20mixer._address, 'Mixer')
await printBalance(senderAccount, 'Sender account')
await depositErc20()
await printBalance(erc20mixer._address, 'Mixer')
await printBalance(senderAccount, 'Sender account')
} else {
printHelp(1)
}
break
case 'balance':
if (args.length === 2 && /^0x[0-9a-fA-F]{40}$/.test(args[1])) {
await init()
await printBalance(args[1])
} else {
printHelp(1)
}
break
case 'withdraw':
if (args.length >= 3 && args.length <= 4 && /^0x[0-9a-fA-F]{124}$/.test(args[1]) && /^0x[0-9a-fA-F]{40}$/.test(args[2])) {
await init()
await printBalance(mixer._address, 'Mixer')
await printBalance(args[2], 'Recipient account')
if (args[3]) {
await withdrawRelay(args[1], args[2], args[3])
} else {
await withdraw(args[1], args[2])
}
await printBalance(mixer._address, 'Mixer')
await printBalance(args[2], 'Recipient account')
} else {
printHelp(1)
}
break
case 'withdrawErc20':
if (args.length >= 3 && args.length <= 4 && /^0x[0-9a-fA-F]{124}$/.test(args[1]) && /^0x[0-9a-fA-F]{40}$/.test(args[2])) {
await init()
await printBalance(erc20mixer._address, 'Mixer')
await printBalance(args[2], 'Recipient account')
if (args[3]) {
await withdrawRelayErc20(args[1], args[2], args[3])
} else {
await withdrawErc20(args[1], args[2])
}
await printBalance(erc20mixer._address, 'Mixer')
await printBalance(args[2], 'Recipient account')
} else {
printHelp(1)
}
break
case 'test':
if (args.length === 1) {
await init()
const note1 = await deposit()
await withdraw(note1, senderAccount)
const note2 = await depositErc20()
await withdrawErc20(note2, senderAccount)
} else {
printHelp(1)
}
break
case 'testRelay':
if (args.length === 1) {
await init()
const note1 = await deposit()
await withdrawRelay(note1, senderAccount, 'http://localhost:8000')
const note2 = await depositErc20()
await withdrawRelayErc20(note2, senderAccount, 'http://localhost:8000')
} else {
printHelp(1)
}
break
default:
printHelp(1)
}
}
}
if (inBrowser) {
window.deposit = deposit
window.depositErc20 = depositErc20
window.withdraw = async () => {
const note = prompt('Enter the note to withdraw')
const recipient = (await web3.eth.getAccounts())[0]
await withdraw(note, recipient)
}
init()
} else {
runConsole(process.argv.slice(2))
.then(() => process.exit(0))
.catch(err => { console.log(err); process.exit(1) })
}