prevent calling onCall in execute arb call

v2/contracts/evm/GatewayEVM.sol

@@ -76,6 +76,16 @@ contract GatewayEVM is
     /// @param data Calldata to pass to the call.
     /// @return The result of the call.
     function _executeArbitraryCall(address destination, bytes calldata data) internal returns (bytes memory) {
+        if (data.length >= 4) {
+            bytes4 functionSelector;
+            assembly {
+                functionSelector := calldataload(data.offset)
+            }
+
+            if (functionSelector == Callable.onCall.selector) {
+                revert NotAllowedToCallOnCall();
+            }
+        }
         (bool success, bytes memory result) = destination.call{ value: msg.value }(data);
         if (!success) revert ExecutionFailed();
 

v2/contracts/evm/interfaces/IGatewayEVM.sol

@@ -80,6 +80,8 @@ interface IGatewayEVMErrors {
 
     /// @notice Error when trying to transfer not whitelisted token to custody.
     error NotWhitelistedInCustody();
+
+    error NotAllowedToCallOnCall();
 }
 
 /// @title IGatewayEVM

v2/contracts/zevm/GatewayZEVM.sol

@@ -285,7 +285,14 @@ contract GatewayZEVM is
             revert GasFeeTransferFailed();
         }
 
-        emit Called(msg.sender, zrc20, receiver, message, CallOptions({ gasLimit: gasLimit, isArbitraryCall: true }), revertOptions);
+        emit Called(
+            msg.sender,
+            zrc20,
+            receiver,
+            message,
+            CallOptions({ gasLimit: gasLimit, isArbitraryCall: true }),
+            revertOptions
+        );
     }
 
     /// @notice Deposit foreign coins into ZRC20.

v2/test/GatewayEVM.t.sol

@@ -182,6 +182,14 @@ contract GatewayEVMTest is Test, IGatewayEVMErrors, IGatewayEVMEvents, IReceiver
         gateway.execute(address(receiver), data);
     }
 
+    function testForwardCallToReceiveOnCallFails() public {
+        bytes memory data = abi.encodeWithSignature("onCall(address,bytes)", address(123), bytes(""));
+
+        vm.prank(tssAddress);
+        vm.expectRevert(NotAllowedToCallOnCall.selector);
+        gateway.execute(address(receiver), data);
+    }
+
     function testExecuteFailsIfDestinationIsZeroAddress() public {
         bytes memory data = abi.encodeWithSignature("receiveNoParams()");
 

v2/test/utils/IReceiverEVM.sol

@@ -36,4 +36,6 @@ interface IReceiverEVMEvents {
     /// @param sender The address of the sender.
     /// @param revertContext Revert Context.
     event ReceivedRevert(address sender, RevertContext revertContext);
+
+    event ReceivedOnCall();
 }

v2/test/utils/ReceiverEVM.sol

@@ -72,6 +72,10 @@ contract ReceiverEVM is IReceiverEVMEvents, ReentrancyGuard {
         emit ReceivedRevert(msg.sender, revertContext);
     }
 
+    function onCall(address sender, bytes calldata message) external returns (bytes memory) {
+        emit ReceivedOnCall();
+    }
+
     /// @notice Receives ETH.
     receive() external payable { }