ethers; tests

TODO

@@ -1,11 +1,9 @@
-* shuffle outputs and inputs
 * utxo data encryption for recipient as for mining
   - combine privkey hash and ethereum public key = address
-* outputs merging
+* outputs merging (second snark with 32 inputs) (poma)
-* switch web3 to etherjs
+* wasmsnark (poma)
-* tests
-* wasmsnark
-* ERC20?
-* design
 * relayer
-* race condition ?
+
+* design
+* race condition ? (sequencer or something)
+* the current trusted setup is not secure

package.json

@@ -21,6 +21,7 @@
     "@nomiclabs/hardhat-waffle": "^2.0.1",
     "@openzeppelin/contracts": "^3.4.0",
     "bignumber.js": "^9.0.0",
+    "chai": "^4.3.4",
     "circom": "^0.5.45",
     "circom_runtime": "^0.1.13",
     "circomlib": "git+https://github.com/tornadocash/circomlib.git#d20d53411d1bef61f38c99a8b36d5d0cc4836aa1",

src/index.js

@@ -1,29 +1,27 @@
 /* eslint-disable no-console */
 const MerkleTree = require('fixed-merkle-tree')
-const Web3 = require('web3')
 const { ethers } = require('hardhat')
-const { BigNumber } = ethers
 const { toFixedHex, poseidonHash2, getExtDataHash, FIELD_SIZE } = require('./utils')
 const Utxo = require('./utxo')
 
-let contract, web3
 const { prove } = require('./prover')
 const MERKLE_TREE_HEIGHT = 5
-const RPC_URL = 'http://localhost:8545'
 
-async function buildMerkleTree() {
+async function buildMerkleTree({ tornadoPool }) {
   console.log('Getting contract state...')
-  const events = await contract.getPastEvents('NewCommitment', { fromBlock: 0, toBlock: 'latest' })
+  const filter = tornadoPool.filters.NewCommitment()
+  const events = await tornadoPool.queryFilter(filter, 0)
+
   const leaves = events
-    .sort((a, b) => a.returnValues.index - b.returnValues.index) // todo sort by event date
+    .sort((a, b) => a.args.index - b.args.index) // todo sort by event date
-    .map((e) => toFixedHex(e.returnValues.commitment))
+    .map((e) => toFixedHex(e.args.commitment))
   // console.log('leaves', leaves)
   return new MerkleTree(MERKLE_TREE_HEIGHT, leaves, { hashFunction: poseidonHash2 })
 }
 
 async function getProof({ inputs, outputs, tree, extAmount, fee, recipient, relayer }) {
   // todo shuffle inputs and outputs
-  if (inputs.length !== 2 || outputs.length !== 2 ) {
+  if (inputs.length !== 2 || outputs.length !== 2) {
     throw new Error('Unsupported number of inputs/outputs')
   }
 
@@ -63,23 +61,23 @@ async function getProof({ inputs, outputs, tree, extAmount, fee, recipient, rela
   let input = {
     root: oldRoot,
     newRoot: tree.root(),
-    inputNullifier: inputs.map(x => x.getNullifier()),
+    inputNullifier: inputs.map((x) => x.getNullifier()),
-    outputCommitment: outputs.map(x => x.getCommitment()),
+    outputCommitment: outputs.map((x) => x.getCommitment()),
     extAmount,
     fee,
     extDataHash,
 
     // data for 2 transaction inputs
-    inAmount: inputs.map(x => x.amount),
+    inAmount: inputs.map((x) => x.amount),
-    inPrivateKey: inputs.map(x => x.privkey),
+    inPrivateKey: inputs.map((x) => x.privkey),
-    inBlinding: inputs.map(x => x.blinding),
+    inBlinding: inputs.map((x) => x.blinding),
     inPathIndices: inputMerklePathIndices,
     inPathElements: inputMerklePathElements,
 
     // data for 2 transaction outputs
-    outAmount: outputs.map(x => x.amount),
+    outAmount: outputs.map((x) => x.amount),
-    outBlinding: outputs.map(x => x.blinding),
+    outBlinding: outputs.map((x) => x.blinding),
-    outPubkey: outputs.map(x => x.pubkey),
+    outPubkey: outputs.map((x) => x.pubkey),
     outPathIndices: outputIndex >> 1,
     outPathElements: outputPath,
   }
@@ -92,8 +90,8 @@ async function getProof({ inputs, outputs, tree, extAmount, fee, recipient, rela
   const args = [
     toFixedHex(input.root),
     toFixedHex(input.newRoot),
-    inputs.map(x => toFixedHex(x.getNullifier())),
+    inputs.map((x) => toFixedHex(x.getNullifier())),
-    outputs.map(x => toFixedHex(x.getCommitment())),
+    outputs.map((x) => toFixedHex(x.getCommitment())),
     toFixedHex(extAmount),
     toFixedHex(fee),
     extData,
@@ -107,7 +105,7 @@ async function getProof({ inputs, outputs, tree, extAmount, fee, recipient, rela
   }
 }
 
-async function deposit() {
+async function deposit({ tornadoPool }) {
   const amount = 1e6
   const inputs = [new Utxo(), new Utxo()]
   const outputs = [new Utxo({ amount }), new Utxo()]
@@ -115,7 +113,7 @@ async function deposit() {
   const { proof, args } = await getProof({
     inputs,
     outputs,
-    tree: await buildMerkleTree(),
+    tree: await buildMerkleTree({ tornadoPool }),
     extAmount: amount,
     fee: 0,
     recipient: 0,
@@ -123,24 +121,25 @@ async function deposit() {
   })
 
   console.log('Sending deposit transaction...')
-  const receipt = await contract.methods
+  const receipt = await tornadoPool.transaction(proof, ...args, {
-    .transaction(proof, ...args)
+    value: amount,
-    .send({ value: amount, from: web3.eth.defaultAccount, gas: 1e6 })
+    gasLimit: 1e6,
-  console.log(`Receipt ${receipt.transactionHash}`)
+  })
+  console.log(`Receipt ${receipt.hash}`)
   return outputs[0]
 }
 
-async function transact(utxo) {
+async function transact({ tornadoPool, utxo }) {
   const inputs = [utxo, new Utxo()]
   const outputs = [
     new Utxo({ amount: utxo.amount / 4 }),
-    new Utxo({ amount: utxo.amount * 3 / 4, privkey: utxo.privkey}),
+    new Utxo({ amount: (utxo.amount * 3) / 4, privkey: utxo.privkey }),
   ]
 
   const { proof, args } = await getProof({
     inputs,
     outputs,
-    tree: await buildMerkleTree(),
+    tree: await buildMerkleTree({ tornadoPool }),
     extAmount: 0,
     fee: 0,
     recipient: 0,
@@ -148,49 +147,28 @@ async function transact(utxo) {
   })
 
   console.log('Sending transfer transaction...')
-  const receipt = await contract.methods
+  const receipt = await tornadoPool.transaction(proof, ...args, { gasLimit: 1e6 })
-    .transaction(proof, ...args)
+  console.log(`Receipt ${receipt.hash}`)
-    .send({ from: web3.eth.defaultAccount, gas: 1e6 })
-  console.log(`Receipt ${receipt.transactionHash}`)
   return outputs[0]
 }
 
-async function withdraw(utxo) {
+async function withdraw({ tornadoPool, utxo, recipient }) {
   const inputs = [utxo, new Utxo()]
   const outputs = [new Utxo(), new Utxo()]
 
   const { proof, args } = await getProof({
     inputs,
     outputs,
-    tree: await buildMerkleTree(),
+    tree: await buildMerkleTree({ tornadoPool }),
     extAmount: FIELD_SIZE.sub(utxo.amount),
     fee: 0,
-    recipient: '0xc2Ba33d4c0d2A92fb4f1a07C273c5d21E688Eb48',
+    recipient,
     relayer: 0,
   })
 
   console.log('Sending withdraw transaction...')
-  const receipt = await contract.methods
+  const receipt = await tornadoPool.transaction(proof, ...args, { gasLimit: 1e6 })
-    .transaction(proof, ...args)
+  console.log(`Receipt ${receipt.hash}`)
-    .send({ from: web3.eth.defaultAccount, gas: 1e6 })
-  console.log(`Receipt ${receipt.transactionHash}`)
-
-  let bal = await web3.eth.getBalance('0xc2Ba33d4c0d2A92fb4f1a07C273c5d21E688Eb48')
-  console.log('balance', bal)
 }
 
-async function main() {
+module.exports = { deposit, withdraw, transact }
-  web3 = new Web3(new Web3.providers.HttpProvider(RPC_URL, { timeout: 5 * 60 * 1000 }), null, {
-    transactionConfirmationBlocks: 1,
-  })
-  netId = await web3.eth.net.getId()
-  const contractData = require('../artifacts/contracts/TornadoPool.sol/TornadoPool.json')
-  contract = new web3.eth.Contract(contractData.abi, '0x0E801D84Fa97b50751Dbf25036d067dCf18858bF')
-  web3.eth.defaultAccount = (await web3.eth.getAccounts())[0]
-
-  const utxo1 = await deposit()
-  const utxo2 = await transact(utxo1)
-  await withdraw(utxo2)
-}
-
-main()

src/utils.js

@@ -1,7 +1,7 @@
 const crypto = require('crypto')
-const ethers = require('ethers')
+const { ethers } = require('hardhat')
 const BigNumber = ethers.BigNumber
-const {poseidon} = require('circomlib')
+const { poseidon } = require('circomlib')
 
 const poseidonHash = (items) => BigNumber.from(poseidon(items).toString())
 const poseidonHash2 = (a, b) => poseidonHash([a, b])
@@ -12,17 +12,19 @@ const FIELD_SIZE = BigNumber.from(
 /** Generate random number of specified byte length */
 const randomBN = (nbytes = 31) => BigNumber.from(crypto.randomBytes(nbytes))
 
-function getExtDataHash({recipient, relayer, encryptedOutput1, encryptedOutput2}) {
+function getExtDataHash({ recipient, relayer, encryptedOutput1, encryptedOutput2 }) {
   const abi = new ethers.utils.AbiCoder()
 
   const encodedData = abi.encode(
     ['tuple(address recipient,address relayer,bytes encryptedOutput1,bytes encryptedOutput2)'],
-    [{
+    [
+      {
         recipient: toFixedHex(recipient, 20),
         relayer: toFixedHex(relayer, 20),
         encryptedOutput1: encryptedOutput1,
         encryptedOutput2: encryptedOutput2,
-      }],
+      },
+    ],
   )
   const hash = ethers.utils.keccak256(encodedData)
   return BigNumber.from(hash).mod(FIELD_SIZE)
@@ -32,8 +34,8 @@ function getExtDataHash({recipient, relayer, encryptedOutput1, encryptedOutput2}
 const toFixedHex = (number, length = 32) =>
   '0x' +
   (number instanceof Buffer
-      ? number.toString('hex')
+    ? number.toString('hex')
-      : BigNumber.from(number).toHexString().slice(2)
+    : BigNumber.from(number).toHexString().slice(2)
   ).padStart(length * 2, '0')
 
 const toBuffer = (value, length) =>
@@ -45,6 +47,14 @@ const toBuffer = (value, length) =>
     'hex',
   )
 
+async function takeSnapshot() {
+  return await ethers.provider.send('evm_snapshot', [])
+}
+
+async function revertSnapshot(id) {
+  await ethers.provider.send('evm_revert', [id])
+}
+
 module.exports = {
   FIELD_SIZE,
   randomBN,
@@ -53,4 +63,6 @@ module.exports = {
   poseidonHash,
   poseidonHash2,
   getExtDataHash,
+  takeSnapshot,
+  revertSnapshot,
 }

src/utxo.js

@@ -10,19 +10,19 @@ function fromPrivkey(privkey) {
 }
 
 class Utxo {
-  constructor({amount, pubkey, privkey, blinding, index} = {}) {
+  constructor({ amount, pubkey, privkey, blinding, index } = {}) {
     if (!pubkey) {
       if (privkey) {
         pubkey = fromPrivkey(privkey).pubkey
       } else {
-        ({pubkey, privkey} = fromPrivkey(randomBN()))
+        ;({ pubkey, privkey } = fromPrivkey(randomBN()))
       }
     }
-    this.amount = BigNumber.from(amount || 0);
+    this.amount = BigNumber.from(amount || 0)
-    this.blinding = blinding || randomBN();
+    this.blinding = blinding || randomBN()
-    this.pubkey = pubkey;
+    this.pubkey = pubkey
-    this.privkey = privkey;
+    this.privkey = privkey
-    this.index = index;
+    this.index = index
   }
 
   getCommitment() {

test/full.test.js

@@ -0,0 +1,45 @@
+/* global ethers */
+const { expect, should } = require('chai')
+should()
+
+const { poseidonHash2, toFixedHex, takeSnapshot, revertSnapshot } = require('../src/utils')
+
+const MERKLE_TREE_HEIGHT = 5
+const MerkleTree = require('fixed-merkle-tree')
+
+const { deposit, transact, withdraw } = require('../src/index')
+
+describe('TornadoPool', () => {
+  let snapshotId, tornadoPool
+
+  /* prettier-ignore */
+  before(async function () {
+    const Verifier = await ethers.getContractFactory('Verifier')
+    const verifier = await Verifier.deploy()
+    await verifier.deployed()
+
+    const tree = new MerkleTree(MERKLE_TREE_HEIGHT, [], { hashFunction: poseidonHash2 })
+    const root = await tree.root()
+
+    const Pool = await ethers.getContractFactory('TornadoPool')
+    tornadoPool = await Pool.deploy(verifier.address, toFixedHex(root))
+
+    snapshotId = await takeSnapshot()
+  })
+
+  it('should deposit, transact and withdraw', async function () {
+    const utxo1 = await deposit({ tornadoPool })
+    const utxo2 = await transact({ tornadoPool, utxo: utxo1 })
+
+    const recipient = '0xc2Ba33d4c0d2A92fb4f1a07C273c5d21E688Eb48'
+    await withdraw({ tornadoPool, utxo: utxo2, recipient })
+
+    let bal = await ethers.provider.getBalance(recipient)
+    expect(bal).to.be.gt(0)
+  })
+
+  afterEach(async () => {
+    await revertSnapshot(snapshotId)
+    snapshotId = await takeSnapshot()
+  })
+})

yarn.lock

@@ -1773,9 +1773,9 @@ blake2b-wasm@^1.1.0:
   dependencies:
     nanoassert "^1.0.0"
 
-"blake2b-wasm@git+https://github.com/jbaylina/blake2b-wasm.git":
+"blake2b-wasm@https://github.com/jbaylina/blake2b-wasm.git":
   version "2.1.0"
-  resolved "git+https://github.com/jbaylina/blake2b-wasm.git#0d5f024b212429c7f50a7f533aa3a2406b5b42b3"
+  resolved "https://github.com/jbaylina/blake2b-wasm.git#0d5f024b212429c7f50a7f533aa3a2406b5b42b3"
   dependencies:
     nanoassert "^1.0.0"
 
@@ -2078,7 +2078,7 @@ caseless@~0.12.0:
   resolved "https://registry.yarnpkg.com/caseless/-/caseless-0.12.0.tgz#1b681c21ff84033c826543090689420d187151dc"
   integrity sha1-G2gcIf+EAzyCZUMJBolCDRhxUdw=
 
-chai@^4.2.0:
+chai@^4.2.0, chai@^4.3.4:
   version "4.3.4"
   resolved "https://registry.yarnpkg.com/chai/-/chai-4.3.4.tgz#b55e655b31e1eac7099be4c08c21964fce2e6c49"
   integrity sha512-yS5H68VYOCtN1cjfwumDSuzn/9c+yza4f3reKXlE5rUg7SFcCEy90gJvydNgOYtblyf4Zi6jIWRnXOgErta0KA==