tornado-core/contracts/ERC20Tornado.sol

60 lines
2.0 KiB
Solidity

// https://tornado.cash
/*
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*/
// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
import "./Tornado.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
contract ERC20Tornado is Tornado {
using SafeERC20 for IERC20;
IERC20 public token;
constructor(
IVerifier _verifier,
IHasher _hasher,
uint256 _denomination,
uint32 _merkleTreeHeight,
IERC20 _token
) Tornado(_verifier, _hasher, _denomination, _merkleTreeHeight) {
token = _token;
}
function _processDeposit() internal override {
require(msg.value == 0, "ETH value is supposed to be 0 for ERC20 instance");
token.safeTransferFrom(msg.sender, address(this), denomination);
}
function _processWithdraw(
address payable _recipient,
address payable _relayer,
uint256 _fee,
uint256 _refund
) internal override {
require(msg.value == _refund, "Incorrect refund amount received by the contract");
token.safeTransfer(_recipient, denomination - _fee);
if (_fee > 0) {
token.safeTransfer(_relayer, _fee);
}
if (_refund > 0) {
(bool success, ) = _recipient.call{ value: _refund }("");
if (!success) {
// let's return _refund back to the relayer
_relayer.transfer(_refund);
}
}
}
}