Allow fee transfer from user to fee collector (#19)

* allow fee transfer from user to fee collector * add support for ERC2771 * rename * update dependency * implemented audit recommendations
gelatodigital · Sep 4, 2023 · c8e5771 · c8e5771
1 parent af36ab7
commit c8e5771
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Showing 4 changed files with 401 additions and 202 deletions.
diff --git a/contracts/GelatoRelayContextERC2771.sol b/contracts/GelatoRelayContextERC2771.sol
@@ -88,6 +88,49 @@ abstract contract GelatoRelayContextERC2771 is GelatoRelayERC2771Base {
         _getFeeToken().transfer(_getFeeCollector(), fee);
     }
 
+    // DANGER! Only use with onlyGelatoRelayERC2771, onlyGelatoRelayConcurrentERC2771,
+    // `_isGelatoRelayERC2771` or `_isGelatoRelayConcurrentERC2771` checks
+    function _transferFromRelayFee() internal {
+        _getFeeToken().transferFrom(
+            _getMsgSender(),
+            _getFeeCollector(),
+            _getFee()
+        );
+    }
+
+    // DANGER! Only use with onlyGelatoRelayERC2771, onlyGelatoRelayConcurrentERC2771,
+    // `_isGelatoRelayERC2771` or `_isGelatoRelayConcurrentERC2771` checks
+    function _transferFromRelayFeeCapped(uint256 _maxFee) internal {
+        uint256 fee = _getFee();
+        require(
+            fee <= _maxFee,
+            "GelatoRelayContextERC2771._transferFromRelayFeeCapped: maxFee"
+        );
+        _getFeeToken().transferFrom(_getMsgSender(), _getFeeCollector(), fee);
+    }
+
+    // DANGER! Only use with onlyGelatoRelayERC2771, onlyGelatoRelayConcurrentERC2771,
+    // `_isGelatoRelayERC2771` or `_isGelatoRelayConcurrentERC2771` checks
+    function _transferFromRelayFeeCappedWithPermit(
+        uint256 _maxFee,
+        uint256 _deadline,
+        uint8 _v,
+        bytes32 _r,
+        bytes32 _s
+    ) internal {
+        uint256 fee = _getFee();
+        require(
+            fee <= _maxFee,
+            "GelatoRelayContextERC2771._transferFromRelayFeeCappedWithPermit: maxFee"
+        );
+
+        address from = _getMsgSender();
+        address token = _getFeeToken();
+
+        token.permit(from, address(this), _maxFee, _deadline, _v, _r, _s);
+        token.transferFrom(from, _getFeeCollector(), fee);
+    }
+
     function _getMsgData() internal view virtual returns (bytes calldata) {
         return
             _isGelatoRelayERC2771(msg.sender)

diff --git a/contracts/lib/TokenUtils.sol b/contracts/lib/TokenUtils.sol
@@ -2,20 +2,45 @@
 pragma solidity ^0.8.1;
 
 import {NATIVE_TOKEN} from "../constants/Tokens.sol";
-import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
 import {Address} from "@openzeppelin/contracts/utils/Address.sol";
+import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+import {
+    IERC20Permit
+} from "@openzeppelin/contracts/token/ERC20/extensions/IERC20Permit.sol";
 import {
     SafeERC20
 } from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
 
 library TokenUtils {
     using SafeERC20 for IERC20;
+    using SafeERC20 for IERC20Permit;
 
     modifier onlyERC20(address _token) {
         require(_token != NATIVE_TOKEN, "TokenUtils.onlyERC20");
         _;
     }
 
+    function permit(
+        address _token,
+        address _owner,
+        address _spender,
+        uint256 _value,
+        uint256 _deadline,
+        uint8 _v,
+        bytes32 _r,
+        bytes32 _s
+    ) internal onlyERC20(_token) {
+        IERC20Permit(_token).safePermit(
+            _owner,
+            _spender,
+            _value,
+            _deadline,
+            _v,
+            _r,
+            _s
+        );
+    }
+
     function transfer(
         address _token,
         address _to,

diff --git a/package.json b/package.json
@@ -38,7 +38,7 @@
   },
   "license": "MIT",
   "dependencies": {
-    "@openzeppelin/contracts": "4.8.3"
+    "@openzeppelin/contracts": "4.9.3"
   },
   "devDependencies": {
     "@nomiclabs/hardhat-ethers": "npm:hardhat-deploy-ethers",
@@ -57,7 +57,7 @@
     "eslint-plugin-prettier": "4.2.1",
     "ethereum-waffle": "3.4.4",
     "ethers": "5.7.0",
-    "hardhat": "2.11.1",
+    "hardhat": "2.17.1",
     "hardhat-deploy": "0.11.14",
     "husky": "8.0.1",
     "lint-staged": "13.0.3",