tests, more docs, minor refactoring

This commit is contained in:
poma 2019-10-04 17:27:47 +03:00
parent 5c3c78e097
commit 6035255a49
4 changed files with 121 additions and 50 deletions

View File

@ -25,21 +25,21 @@ contract ERC20Mixer is Mixer {
uint256 _emptyElement,
address payable _operator,
address _token,
uint256 _mixDenomination
) Mixer(_verifier, _mixDenomination, _merkleTreeHeight, _emptyElement, _operator) public {
uint256 _denomination
) Mixer(_verifier, _denomination, _merkleTreeHeight, _emptyElement, _operator) public {
token = _token;
userEther = _userEther;
}
function _processDeposit() internal {
require(msg.value == userEther, "Please send `userEther` ETH along with transaction");
safeErc20TransferFrom(msg.sender, address(this), mixDenomination);
safeErc20TransferFrom(msg.sender, address(this), denomination);
}
function _processWithdraw(address payable _receiver, address payable _relayer, uint256 _fee) internal {
_receiver.transfer(userEther);
safeErc20Transfer(_receiver, mixDenomination - _fee);
safeErc20Transfer(_receiver, denomination - _fee);
if (_fee > 0) {
safeErc20Transfer(_relayer, _fee);
}

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@ -16,21 +16,21 @@ import "./Mixer.sol";
contract ETHMixer is Mixer {
constructor(
address _verifier,
uint256 _mixDenomination,
uint256 _denomination,
uint8 _merkleTreeHeight,
uint256 _emptyElement,
address payable _operator
) Mixer(_verifier, _mixDenomination, _merkleTreeHeight, _emptyElement, _operator) public {
) Mixer(_verifier, _denomination, _merkleTreeHeight, _emptyElement, _operator) public {
}
function _processWithdraw(address payable _receiver, address payable _relayer, uint256 _fee) internal {
_receiver.transfer(mixDenomination - _fee);
_receiver.transfer(denomination - _fee);
if (_fee > 0) {
_relayer.transfer(_fee);
}
}
function _processDeposit() internal {
require(msg.value == mixDenomination, "Please send `mixDenomination` ETH along with transaction");
require(msg.value == denomination, "Please send `mixDenomination` ETH along with transaction");
}
}

View File

@ -18,16 +18,23 @@ contract IVerifier {
}
contract Mixer is MerkleTreeWithHistory {
bool public isDepositsEnabled = true;
bool public isVerifierUpdateAllowed = true;
// operator can disable new deposits in case of emergency
// it also receives a relayer fee
address payable public operator;
uint256 public denomination;
mapping(uint256 => bool) public nullifierHashes;
// we store all commitments just to prevent accidental deposits with the same commitment
mapping(uint256 => bool) public commitments;
IVerifier public verifier;
uint256 public mixDenomination;
// operator can
// - receive a relayer fee
// - disable new deposits in case of emergency
// - update snark verification key until this ability is permanently disabled
address payable public operator;
bool public isDepositsEnabled = true;
bool public isVerifierUpdateAllowed = true;
modifier onlyOperator {
require(msg.sender == operator, "Only operator can call this function.");
_;
}
event Deposit(uint256 indexed commitment, uint256 leafIndex, uint256 timestamp);
event Withdraw(address to, uint256 nullifierHash, address indexed relayer, uint256 fee);
@ -41,26 +48,22 @@ contract Mixer is MerkleTreeWithHistory {
*/
constructor(
address _verifier,
uint256 _mixDenomination,
uint256 _denomination,
uint8 _merkleTreeHeight,
uint256 _emptyElement,
address payable _operator
) MerkleTreeWithHistory(_merkleTreeHeight, _emptyElement) public {
verifier = IVerifier(_verifier);
operator = _operator;
mixDenomination = _mixDenomination;
denomination = _denomination;
}
/**
@dev Deposit funds into mixer. The caller must send value equal to `mixDenomination` of this mixer.
@param commitment the note commitment, which is PedersenHash(nullifier + secret)
*/
/**
@dev Deposit funds into the mixer. The caller must send ETH value equal to `userEther` of this mixer.
The caller also has to have at least `mixDenomination` amount approved for the mixer.
@dev Deposit funds into mixer. The caller must send (for ETH) or approve (for ERC20) value equal to or `denomination` of this mixer.
@param commitment the note commitment, which is PedersenHash(nullifier + secret)
*/
function deposit(uint256 commitment) public payable {
require(isDepositsEnabled, "deposits disabled");
require(isDepositsEnabled, "deposits are disabled");
require(!commitments[commitment], "The commitment has been submitted");
_processDeposit();
_insert(commitment);
@ -68,6 +71,10 @@ contract Mixer is MerkleTreeWithHistory {
emit Deposit(commitment, next_index - 1, block.timestamp);
}
/** @dev this function is defined in a child contract */
function _processDeposit() internal {}
/**
@dev Withdraw deposit from the mixer. `a`, `b`, and `c` are zkSNARK proof data, and input is an array of circuit public inputs
`input` array consists of:
@ -82,7 +89,7 @@ contract Mixer is MerkleTreeWithHistory {
address payable receiver = address(input[2]);
address payable relayer = address(input[3]);
uint256 fee = input[4];
require(fee < mixDenomination, "Fee exceeds transfer value");
require(fee < denomination, "Fee exceeds transfer value");
require(!nullifierHashes[nullifierHash], "The note has been already spent");
require(isKnownRoot(root), "Cannot find your merkle root"); // Make sure to use a recent one
@ -92,32 +99,41 @@ contract Mixer is MerkleTreeWithHistory {
emit Withdraw(receiver, nullifierHash, relayer, fee);
}
function toggleDeposits() external {
require(msg.sender == operator, "unauthorized");
isDepositsEnabled = !isDepositsEnabled;
}
function updateVerifier(address newVerifier) external {
require(isVerifierUpdateAllowed, "verifier updates are disabled");
require(msg.sender == operator, "unauthorized");
verifier = IVerifier(newVerifier);
}
function disableVerifierUpdate() external {
require(msg.sender == operator, "unauthorized");
isVerifierUpdateAllowed = false;
}
function changeOperator(address payable _newAccount) external {
require(msg.sender == operator, "unauthorized");
operator = _newAccount;
}
/** @dev this function is defined in a child contract */
function _processWithdraw(address payable _receiver, address payable _relayer, uint256 _fee) internal {}
/** @dev whether a note is already spent */
function isSpent(uint256 nullifier) public view returns(bool) {
return nullifierHashes[nullifier];
}
function _processDeposit() internal {}
function _processWithdraw(address payable _receiver, address payable _relayer, uint256 _fee) internal {}
/**
@dev Allow operator to temporarily disable new deposits. This is needed to protect users funds in case a vulnerability is discovered.
It does not affect existing deposits.
*/
function toggleDeposits() external onlyOperator {
isDepositsEnabled = !isDepositsEnabled;
}
/**
@dev allow operator to update SNARK verification keys. This is needed to update keys after the final trusted setup ceremony is held.
After that operator is supposed to permanently disable this ability.
*/
function updateVerifier(address newVerifier) external onlyOperator {
require(isVerifierUpdateAllowed, "Verifier updates have been disabled.");
verifier = IVerifier(newVerifier);
}
/**
@dev an option for operator to permanently disable verification keys update ability.
This is supposed to be called after the final trusted setup ceremony is held.
*/
function disableVerifierUpdate() external onlyOperator {
isVerifierUpdateAllowed = false;
}
/** @dev operator can change his address */
function changeOperator(address payable _newAccount) external onlyOperator {
operator = _newAccount;
}
}

View File

@ -90,7 +90,7 @@ contract('ETHMixer', accounts => {
describe('#constructor', () => {
it('should initialize', async () => {
const etherDenomination = await mixer.mixDenomination()
const etherDenomination = await mixer.denomination()
etherDenomination.should.be.eq.BN(toBN(value))
})
})
@ -116,11 +116,11 @@ contract('ETHMixer', accounts => {
let commitment = 42;
(await mixer.isDepositsEnabled()).should.be.equal(true)
const err = await mixer.toggleDeposits({ from: accounts[1] }).should.be.rejected
err.reason.should.be.equal('unauthorized')
err.reason.should.be.equal('Only operator can call this function.')
await mixer.toggleDeposits({ from: sender });
(await mixer.isDepositsEnabled()).should.be.equal(false)
let error = await mixer.deposit(commitment, { value, from: sender }).should.be.rejected
error.reason.should.be.equal('deposits disabled')
error.reason.should.be.equal('deposits are disabled')
})
it('should throw if there is a such commitment', async () => {
@ -416,11 +416,66 @@ contract('ETHMixer', accounts => {
const newOperator = accounts[7]
const error = await mixer.changeOperator(newOperator, { from: accounts[7] }).should.be.rejected
error.reason.should.be.equal('unauthorized')
error.reason.should.be.equal('Only operator can call this function.')
})
})
describe('#updateVerifier', () => {
it('should work', async () => {
let operator = await mixer.operator()
operator.should.be.equal(sender)
const newVerifier = accounts[7]
await mixer.updateVerifier(newVerifier).should.be.fulfilled
verifier = await mixer.verifier()
verifier.should.be.equal(newVerifier)
})
it('cannot change from different address', async () => {
let operator = await mixer.operator()
operator.should.be.equal(sender)
const newVerifier = accounts[7]
const error = await mixer.updateVerifier(newVerifier, { from: accounts[7] }).should.be.rejected
error.reason.should.be.equal('Only operator can call this function.')
})
})
describe('#disableVerifierUpdate', () => {
it('should work', async () => {
let operator = await mixer.operator()
operator.should.be.equal(sender)
let isVerifierUpdateAllowed = await mixer.isVerifierUpdateAllowed()
isVerifierUpdateAllowed.should.be.equal(true)
await mixer.disableVerifierUpdate().should.be.fulfilled
newValue = await mixer.isVerifierUpdateAllowed()
newValue.should.be.equal(false)
})
it('cannot update verifier after this function is called', async () => {
let operator = await mixer.operator()
operator.should.be.equal(sender)
let isVerifierUpdateAllowed = await mixer.isVerifierUpdateAllowed()
isVerifierUpdateAllowed.should.be.equal(true)
await mixer.disableVerifierUpdate().should.be.fulfilled
newValue = await mixer.isVerifierUpdateAllowed()
newValue.should.be.equal(false)
const newVerifier = accounts[7]
const error = await mixer.updateVerifier(newVerifier).should.be.rejected
error.reason.should.be.equal('Verifier updates have been disabled.')
})
})
afterEach(async () => {
await revertSnapshot(snapshotId.result)
// eslint-disable-next-line require-atomic-updates