From f12611f4df0bc981fb32d5549e4d0155a578010e Mon Sep 17 00:00:00 2001
From: thal0x <thal0x.eth@gmail.com>
Date: Wed, 6 Nov 2024 08:48:06 -0600
Subject: [PATCH] only allow gateway as caller in GoFastCaller

---
 solidity/src/FastTransferGateway.sol           |  3 ++-
 .../{GoFastMulticall.sol => GoFastCaller.sol}  | 18 +++++++++++++++++-
 solidity/test/ERC7683.t.sol                    |  6 ++++--
 solidity/test/FastTransferGateway.t.sol        |  6 ++++--
 4 files changed, 27 insertions(+), 6 deletions(-)
 rename solidity/src/{GoFastMulticall.sol => GoFastCaller.sol} (60%)

diff --git a/solidity/src/FastTransferGateway.sol b/solidity/src/FastTransferGateway.sol
index d461906..090561f 100644
--- a/solidity/src/FastTransferGateway.sol
+++ b/solidity/src/FastTransferGateway.sol
@@ -16,7 +16,8 @@ import {OrderEncoder} from "./libraries/OrderEncoder.sol";
 
 import {IPermit2} from "./interfaces/IPermit2.sol";
 import {IMailbox} from "./interfaces/hyperlane/IMailbox.sol";
-import {GoFastCaller} from "./GoFastMulticall.sol";
+import {GoFastCaller} from "./GoFastCaller.sol";
+
 // Structure that contains the order details required to settle or refund an order
 
 struct SettlementDetails {
diff --git a/solidity/src/GoFastMulticall.sol b/solidity/src/GoFastCaller.sol
similarity index 60%
rename from solidity/src/GoFastMulticall.sol
rename to solidity/src/GoFastCaller.sol
index 46522e9..44dd486 100644
--- a/solidity/src/GoFastMulticall.sol
+++ b/solidity/src/GoFastCaller.sol
@@ -3,12 +3,28 @@ pragma solidity ^0.8.13;
 
 import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
 import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
+import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
 
-contract GoFastCaller {
+contract GoFastCaller is Ownable {
     using SafeERC20 for IERC20;
 
+    address public gateway;
+
+    constructor(address _owner) Ownable(_owner) {}
+
+    function setGateway(address _gateway) external onlyOwner {
+        gateway = _gateway;
+    }
+
+    modifier onlyGateway() {
+        require(gateway != address(0), "GoFastCaller: gateway not set");
+        require(msg.sender == gateway, "GoFastCaller: sender not gateway");
+        _;
+    }
+
     function execute(address _target, address _token, uint256 _amount, bytes memory _data)
         external
+        onlyGateway
         returns (bool, bytes memory)
     {
         IERC20(_token).forceApprove(_target, _amount);
diff --git a/solidity/test/ERC7683.t.sol b/solidity/test/ERC7683.t.sol
index b37cd20..74f03cd 100644
--- a/solidity/test/ERC7683.t.sol
+++ b/solidity/test/ERC7683.t.sol
@@ -12,7 +12,7 @@ import {IPermit2} from "../src/interfaces/IPermit2.sol";
 import {OnchainCrossChainOrder, GaslessCrossChainOrder} from "../src/erc7683/ERC7683.sol";
 import {GoFastERC7683, OrderData} from "../src/GoFastERC7683.sol";
 import {OrderEncoder} from "../src/libraries/OrderEncoder.sol";
-import {GoFastCaller} from "../src/GoFastMulticall.sol";
+import {GoFastCaller} from "../src/GoFastCaller.sol";
 
 interface IUniswapV2Router02 {
     function swapExactTokensForTokens(
@@ -56,7 +56,7 @@ contract ERC7683Test is Test {
         solver = address(2);
         mailbox = address(0x979Ca5202784112f4738403dBec5D0F3B9daabB9);
 
-        GoFastCaller goFastCaller = new GoFastCaller();
+        GoFastCaller goFastCaller = new GoFastCaller(address(this));
 
         FastTransferGateway gatewayImpl = new FastTransferGateway();
         ERC1967Proxy gatewayProxy = new ERC1967Proxy(
@@ -74,6 +74,8 @@ contract ERC7683Test is Test {
         );
         gateway = FastTransferGateway(address(gatewayProxy));
 
+        goFastCaller.setGateway(address(gateway));
+
         GoFastERC7683 goFastERC7683Impl = new GoFastERC7683();
         ERC1967Proxy goFastERC7683Proxy = new ERC1967Proxy(
             address(goFastERC7683Impl),
diff --git a/solidity/test/FastTransferGateway.t.sol b/solidity/test/FastTransferGateway.t.sol
index 20f8483..197981b 100644
--- a/solidity/test/FastTransferGateway.t.sol
+++ b/solidity/test/FastTransferGateway.t.sol
@@ -11,7 +11,7 @@ import {TypeCasts} from "../src/libraries/TypeCasts.sol";
 import {OrderEncoder} from "../src/libraries/OrderEncoder.sol";
 import {IPermit2} from "../src/interfaces/IPermit2.sol";
 import {IMailbox} from "../src/interfaces/hyperlane/IMailbox.sol";
-import {GoFastCaller} from "../src/GoFastMulticall.sol";
+import {GoFastCaller} from "../src/GoFastCaller.sol";
 
 interface IUniswapV2Router02 {
     function swapExactTokensForTokens(
@@ -55,7 +55,7 @@ contract FastTransferGatewayTest is Test {
         solver = address(2);
         mailbox = address(0x979Ca5202784112f4738403dBec5D0F3B9daabB9);
 
-        GoFastCaller _goFastCaller = new GoFastCaller();
+        GoFastCaller _goFastCaller = new GoFastCaller(address(this));
         goFastCaller = address(_goFastCaller);
         FastTransferGateway gatewayImpl = new FastTransferGateway();
         ERC1967Proxy gatewayProxy = new ERC1967Proxy(
@@ -72,6 +72,8 @@ contract FastTransferGatewayTest is Test {
             )
         );
         gateway = FastTransferGateway(address(gatewayProxy));
+
+        _goFastCaller.setGateway(address(gateway));
     }
 
     function test_submitAndSettle() public {