feat(validium): disallow arbitrary from address in ERC20 gateway

foundry.lock

@@ -0,0 +1,11 @@
+{
+  "lib/ds-test": {
+    "rev": "e282159d5170298eb2455a6c05280ab5a73a4ef0"
+  },
+  "lib/forge-std": {
+    "rev": "978ac6fadb62f5f0b723c996f64be52eddba6801"
+  },
+  "lib/solmate": {
+    "rev": "c892309933b25c03d32b1b0d674df7ae292ba925"
+  }
+}

src/test/validium/FastWithdrawVault.t.sol

@@ -268,7 +268,8 @@ contract FastWithdrawVaultTest is ValidiumTestBase {
                     address(messenger),
                     address(template),
                     address(factory),
-                    address(rollup)
+                    address(rollup),
+                    address(1) // wethGateway - placeholder for tests
                 )
             )
         );

src/test/validium/L1ERC20GatewayValidium.t.sol

@@ -14,6 +14,7 @@ import {AddressAliasHelper} from "../../libraries/common/AddressAliasHelper.sol"
 import {IL1ERC20GatewayValidium} from "../../validium/IL1ERC20GatewayValidium.sol";
 import {IL2ERC20GatewayValidium} from "../../validium/IL2ERC20GatewayValidium.sol";
 import {L1ERC20GatewayValidium} from "../../validium/L1ERC20GatewayValidium.sol";
+import {L1WETHGatewayValidium} from "../../validium/L1WETHGatewayValidium.sol";
 import {ScrollChainValidium} from "../../validium/ScrollChainValidium.sol";
 
 import {TransferReentrantToken} from "../mocks/tokens/TransferReentrantToken.sol";
@@ -46,6 +47,7 @@ contract L1ERC20GatewayValidiumTest is ValidiumTestBase {
     ScrollStandardERC20 private template;
     ScrollStandardERC20Factory private factory;
     L2StandardERC20Gateway private counterpartGateway;
+    L1WETHGatewayValidium private wethGateway = L1WETHGatewayValidium(address(1)); // placeholder for tests
 
     MockERC20 private l1Token;
     MockERC20 private l2Token;
@@ -120,23 +122,43 @@ contract L1ERC20GatewayValidiumTest is ValidiumTestBase {
         _deposit(address(this), amount, recipient, gasLimit);
     }
 
-    function testDepositERC20WithSender(
-        address sender,
+    function testDepositERC20WrongKey(
         uint256 amount,
         bytes memory recipient,
         uint256 gasLimit
     ) public {
-        _deposit(sender, amount, recipient, gasLimit);
+        (uint256 keyId, ) = rollup.getLatestEncryptionKey();
+        hevm.expectRevert(ScrollChainValidium.ErrorUnknownEncryptionKey.selector);
+        gateway.depositERC20(address(l1Token), recipient, amount, gasLimit, keyId + 1);
     }
 
-    function testDepositERC20WrongKey(
+    function testDepositERC20WithRealSenderUnauthorized(
+        address attacker,
+        address victim,
         uint256 amount,
         bytes memory recipient,
         uint256 gasLimit
     ) public {
+        hevm.assume(attacker != address(0));
+        hevm.assume(attacker != address(wethGateway));
+
+        amount = bound(amount, 1, l1Token.balanceOf(address(this)));
+        gasLimit = bound(gasLimit, defaultGasLimit / 2, defaultGasLimit);
         (uint256 keyId, ) = rollup.getLatestEncryptionKey();
-        hevm.expectRevert(ScrollChainValidium.ErrorUnknownEncryptionKey.selector);
-        gateway.depositERC20(address(l1Token), recipient, amount, gasLimit, keyId + 1);
+
+        // Transfer tokens to attacker
+        l1Token.transfer(attacker, amount);
+
+        // Attacker approves gateway
+        hevm.startPrank(attacker);
+        l1Token.approve(address(gateway), amount);
+
+        // Attacker tries to call depositERC20 with victim as _realSender
+        // This should revert with ErrorCallerNotWethGateway
+        hevm.expectRevert(L1ERC20GatewayValidium.ErrorCallerNotWethGateway.selector);
+        gateway.depositERC20(address(l1Token), victim, recipient, amount, gasLimit, keyId);
+
+        hevm.stopPrank();
     }
 
     function testDepositReentrantToken(uint256 amount) public {
@@ -407,12 +429,11 @@ contract L1ERC20GatewayValidiumTest is ValidiumTestBase {
         if (amount == 0) {
             (uint256 keyId, ) = rollup.getLatestEncryptionKey();
             hevm.expectRevert(L1ERC20GatewayValidium.ErrorAmountIsZero.selector);
-            if (from == address(this)) {
-                gateway.depositERC20(address(l1Token), recipient, amount, gasLimit, keyId);
-            } else {
-                gateway.depositERC20(address(l1Token), from, recipient, amount, gasLimit, keyId);
-            }
+            gateway.depositERC20(address(l1Token), recipient, amount, gasLimit, keyId);
         } else {
+            // Note: from parameter is only used in event expectations, not in actual calls
+            // The depositERC20 function always uses msg.sender for actual deposits
+
             // emit QueueTransaction from L1MessageQueueV2
             {
                 hevm.expectEmit(true, true, false, true);
@@ -434,11 +455,7 @@ contract L1ERC20GatewayValidiumTest is ValidiumTestBase {
             uint256 feeVaultBalance = address(feeVault).balance;
             assertEq(l1Messenger.messageSendTimestamp(keccak256(xDomainCalldata)), 0);
             (uint256 keyId, ) = rollup.getLatestEncryptionKey();
-            if (from == address(this)) {
-                gateway.depositERC20(address(l1Token), recipient, amount, gasLimit, keyId);
-            } else {
-                gateway.depositERC20(address(l1Token), from, recipient, amount, gasLimit, keyId);
-            }
+            gateway.depositERC20(address(l1Token), recipient, amount, gasLimit, keyId);
             assertEq(amount + gatewayBalance, l1Token.balanceOf(address(gateway)));
             assertEq(feeVaultBalance, address(feeVault).balance);
             assertGt(l1Messenger.messageSendTimestamp(keccak256(xDomainCalldata)), 0);
@@ -456,7 +473,8 @@ contract L1ERC20GatewayValidiumTest is ValidiumTestBase {
                     address(messenger),
                     address(template),
                     address(factory),
-                    address(rollup)
+                    address(rollup),
+                    address(wethGateway)
                 )
             )
         );

src/test/validium/L1WETHGatewayValidium.t.sol

@@ -64,9 +64,24 @@ contract L1WETHGatewayValidiumTest is ValidiumTestBase {
         counterpartGateway = new L2StandardERC20Gateway(address(1), address(1), address(1), address(factory));
 
         // Deploy L1 contracts
-        gateway = _deployGateway(address(l1Messenger));
+        gateway = L1ERC20GatewayValidium(_deployProxy(address(0)));
         wethGateway = new L1WETHGatewayValidium(address(weth), address(gateway));
 
+        // Upgrade gateway implementation with actual wethGateway address
+        admin.upgrade(
+            ITransparentUpgradeableProxy(address(gateway)),
+            address(
+                new L1ERC20GatewayValidium(
+                    address(counterpartGateway),
+                    address(l1Messenger),
+                    address(template),
+                    address(factory),
+                    address(rollup),
+                    address(wethGateway)
+                )
+            )
+        );
+
         // Initialize L1 contracts
         gateway.initialize();
 
@@ -146,21 +161,4 @@ contract L1WETHGatewayValidiumTest is ValidiumTestBase {
             assertGt(l1Messenger.messageSendTimestamp(keccak256(xDomainCalldata)), 0);
         }
     }
-
-    function _deployGateway(address messenger) internal returns (L1ERC20GatewayValidium _gateway) {
-        _gateway = L1ERC20GatewayValidium(_deployProxy(address(0)));
-
-        admin.upgrade(
-            ITransparentUpgradeableProxy(address(_gateway)),
-            address(
-                new L1ERC20GatewayValidium(
-                    address(counterpartGateway),
-                    address(messenger),
-                    address(template),
-                    address(factory),
-                    address(rollup)
-                )
-            )
-        );
-    }
 }

src/validium/L1ERC20GatewayValidium.sol

@@ -34,6 +34,9 @@ contract L1ERC20GatewayValidium is ScrollGatewayBase, IL1ERC20GatewayValidium {
     /// @dev Error thrown when amount is zero.
     error ErrorAmountIsZero();
 
+    /// @dev Error thrown when caller is not the WETH gateway.
+    error ErrorCallerNotWethGateway();
+
     /*************
      * Constants *
      *************/
@@ -47,6 +50,9 @@ contract L1ERC20GatewayValidium is ScrollGatewayBase, IL1ERC20GatewayValidium {
     /// @notice The address of ScrollChainValidium contract in L2.
     address public immutable scrollChainValidium;
 
+    /// @notice The address of L1WETHGatewayValidium contract.
+    address public immutable wethGateway;
+
     /*************
      * Variables *
      *************/
@@ -67,18 +73,22 @@ contract L1ERC20GatewayValidium is ScrollGatewayBase, IL1ERC20GatewayValidium {
     /// @param _messenger The address of `L1ScrollMessenger` contract in L1.
     /// @param _l2TokenImplementation The address of `ScrollStandardERC20` implementation in L2.
     /// @param _l2TokenFactory The address of `ScrollStandardERC20Factory` contract in L2.
+    /// @param _scrollChainValidium The address of `ScrollChainValidium` contract in L2.
+    /// @param _wethGateway The address of `L1WETHGatewayValidium` contract.
     constructor(
         address _counterpart,
         address _messenger,
         address _l2TokenImplementation,
         address _l2TokenFactory,
-        address _scrollChainValidium
+        address _scrollChainValidium,
+        address _wethGateway
     ) ScrollGatewayBase(_counterpart, address(0), _messenger) {
         _disableInitializers();
 
         l2TokenImplementation = _l2TokenImplementation;
         l2TokenFactory = _l2TokenFactory;
         scrollChainValidium = _scrollChainValidium;
+        wethGateway = _wethGateway;
     }
 
     /// @notice Initialize the storage of L1ERC20GatewayValidium.
@@ -123,6 +133,9 @@ contract L1ERC20GatewayValidium is ScrollGatewayBase, IL1ERC20GatewayValidium {
         uint256 _gasLimit,
         uint256 _keyId
     ) external payable override {
+        // Only the WETH gateway can call this function to preserve the real sender
+        if (_msgSender() != wethGateway) revert ErrorCallerNotWethGateway();
+
         _deposit(_token, _realSender, _to, _amount, new bytes(0), _gasLimit, _keyId);
     }