Merge pull request #18 from immutable/smr-1935-erc20-withdraw-L1

Smr 1935 erc20 withdraw l1

script/DeployRootContracts.s.sol

@@ -21,6 +21,7 @@ contract DeployRootContracts is Script {
         uint256 rootPrivateKey = vm.envUint("ROOT_PRIVATE_KEY");
         string memory rootRpcUrl = vm.envString("ROOT_RPC_URL");
         string memory deployEnvironment = vm.envString("ENVIRONMENT");
+        address rootGateway = vm.envAddress("ROOT_GATEWAY_ADDRESS");
 
         /**
          * DEPLOY ROOT CHAIN CONTRACTS
@@ -36,18 +37,17 @@ contract DeployRootContracts is Script {
 
         RootERC20Bridge rootERC20BridgeImplementation = new RootERC20Bridge();
         rootERC20BridgeImplementation.initialize(
-            address(1), address(1), "filler", address(1), address(1), address(1), 1
+            address(1), address(1), "filler", address(1), address(1), address(1), "filler_child_name", 1
         );
         TransparentUpgradeableProxy rootERC20BridgeProxy = new TransparentUpgradeableProxy(
             address(rootERC20BridgeImplementation),
             address(proxyAdmin),
             ""
         );
 
-        RootAxelarBridgeAdaptor rootBridgeAdaptorImplementation = new RootAxelarBridgeAdaptor();
-        rootBridgeAdaptorImplementation.initialize(
-            address(rootERC20BridgeImplementation), "Filler", address(1), address(1)
-        );
+        RootAxelarBridgeAdaptor rootBridgeAdaptorImplementation = new RootAxelarBridgeAdaptor(rootGateway);
+        rootBridgeAdaptorImplementation.initialize(address(rootERC20BridgeImplementation), "Filler", address(1));
+
         TransparentUpgradeableProxy rootBridgeAdaptorProxy = new TransparentUpgradeableProxy(
             address(rootBridgeAdaptorImplementation),
             address(proxyAdmin),

script/InitializeRootContracts.s.sol

@@ -24,7 +24,6 @@ struct InitializeRootContractsParams {
     address rootIMXToken;
     address rootWETHToken;
     string childChainName;
-    address rootGateway;
     address rootGasService;
     uint256 initialIMXCumulativeDepositLimit;
 }
@@ -42,7 +41,6 @@ contract InitializeRootContracts is Script {
             rootIMXToken: vm.envAddress("ROOT_IMX_ADDRESS"),
             rootWETHToken: vm.envAddress("ROOT_WETH_ADDRESS"),
             childChainName: vm.envString("CHILD_CHAIN_NAME"),
-            rootGateway: vm.envAddress("ROOT_GATEWAY_ADDRESS"),
             rootGasService: vm.envAddress("ROOT_GAS_SERVICE_ADDRESS"),
             initialIMXCumulativeDepositLimit: vm.envUint("INITIAL_IMX_CUMULATIVE_DEPOSIT_LIMIT")
         });
@@ -63,13 +61,13 @@ contract InitializeRootContracts is Script {
             params.rootChainChildTokenTemplate,
             params.rootIMXToken,
             params.rootWETHToken,
+            params.childChainName,
             params.initialIMXCumulativeDepositLimit
         );
 
         params.rootBridgeAdaptor.initialize(
             address(params.rootERC20Bridge), // root bridge
             params.childChainName, // child chain name
-            params.rootGateway, // axelar gateway
             params.rootGasService // axelar gas service
         );
 

src/child/ChildAxelarBridgeAdaptor.sol

@@ -22,7 +22,6 @@ contract ChildAxelarBridgeAdaptor is
     /// @notice Address of bridge to relay messages to.
     IChildERC20Bridge public childBridge;
     IAxelarGasService public gasService;
-    string public rootBridgeAdaptor;
     string public rootChain;
 
     constructor(address _gateway) AxelarExecutable(_gateway) {}
@@ -39,7 +38,6 @@ contract ChildAxelarBridgeAdaptor is
         childBridge = IChildERC20Bridge(_childBridge);
         rootChain = _rootChain;
         gasService = IAxelarGasService(_gasService);
-        rootBridgeAdaptor = childBridge.rootERC20BridgeAdaptor();
     }
 
     /**
@@ -54,15 +52,15 @@ contract ChildAxelarBridgeAdaptor is
         }
 
         // Load from storage.
-        string memory _rootBridgeAdaptor = rootBridgeAdaptor;
+        string memory _rootBridgeAdaptor = childBridge.rootERC20BridgeAdaptor();
         string memory _rootChain = rootChain;
 
         gasService.payNativeGasForContractCall{value: msg.value}(
             address(this), _rootChain, _rootBridgeAdaptor, payload, refundRecipient
         );
 
         gateway.callContract(_rootChain, _rootBridgeAdaptor, payload);
-        emit AxelarMessage(_rootChain, _rootBridgeAdaptor, payload);
+        emit AxelarMessageSent(_rootChain, _rootBridgeAdaptor, payload);
     }
 
     /**
@@ -73,6 +71,7 @@ contract ChildAxelarBridgeAdaptor is
         internal
         override
     {
+        emit AdaptorExecute(sourceChain_, sourceAddress_, payload_);
         childBridge.onMessageReceive(sourceChain_, sourceAddress_, payload_);
     }
 }

src/child/ChildERC20Bridge.sol

@@ -109,20 +109,21 @@ contract ChildERC20Bridge is
         if (!Strings.equal(messageSourceChain, rootChain)) {
             revert InvalidSourceChain();
         }
-
         if (!Strings.equal(sourceAddress, rootERC20BridgeAdaptor)) {
             revert InvalidSourceAddress();
         }
-        if (data.length == 0) {
-            revert InvalidData();
+        if (data.length <= 32) {
+            // Data must always be greater than 32.
+            // 32 bytes for the signature, and at least some information for the payload
+            revert InvalidData("Data too short");
         }
 
         if (bytes32(data[:32]) == MAP_TOKEN_SIG) {
             _mapToken(data);
         } else if (bytes32(data[:32]) == DEPOSIT_SIG) {
             _deposit(data[32:]);
         } else {
-            revert InvalidData();
+            revert InvalidData("Unsupported action signature");
         }
     }
 

src/interfaces/child/IChildAxelarBridgeAdaptor.sol

@@ -12,5 +12,7 @@ interface IChildAxelarBridgeAdaptorErrors {
 
 interface IChildAxelarBridgeAdaptorEvents {
     /// @notice Emitted when an Axelar message is sent to the root chain.
-    event AxelarMessage(string indexed rootChain, string indexed rootBridgeAdaptor, bytes indexed payload);
+    event AxelarMessageSent(string indexed rootChain, string indexed rootBridgeAdaptor, bytes indexed payload);
+    /// @notice Emitted when an Axelar message is received from the root chain.
+    event AdaptorExecute(string sourceChain, string sourceAddress_, bytes payload_);
 }

src/interfaces/child/IChildERC20Bridge.sol

@@ -73,7 +73,7 @@ interface IChildERC20BridgeErrors {
     /// @notice Error when a message is given to the bridge from an address not the designated bridge adaptor.
     error NotBridgeAdaptor();
     /// @notice Error when the message's payload is not valid.
-    error InvalidData();
+    error InvalidData(string reason);
     /// @notice Error when the message's source chain is not valid.
     error InvalidSourceChain();
     /// @notice Error when the source chain's message sender is not a recognised address.

src/interfaces/root/IRootAxelarBridgeAdaptor.sol

@@ -14,5 +14,7 @@ interface IRootAxelarBridgeAdaptorErrors {
 
 interface IRootAxelarBridgeAdaptorEvents {
     /// @notice Emitted when an Axelar message is sent to the child chain.
-    event AxelarMessage(string indexed childChain, string indexed childBridgeAdaptor, bytes indexed payload);
+    event AxelarMessageSent(string indexed childChain, string indexed childBridgeAdaptor, bytes indexed payload);
+    /// @notice Emitted when an Axelar message is received from the child chain.
+    event AdaptorExecute(string sourceChain, string sourceAddress_, bytes payload_);
 }

src/interfaces/root/IRootERC20Bridge.sol

@@ -5,6 +5,14 @@ import {IERC20Metadata} from "@openzeppelin/contracts/token/ERC20/extensions/IER
 
 interface IRootERC20Bridge {
     function childBridgeAdaptor() external view returns (string memory);
+    /**
+     * @notice Receives a bridge message from child chain, parsing the message type then executing.
+     * @param sourceChain The chain the message originated from.
+     * @param sourceAddress The address the message originated from.
+     * @param data The data payload of the message.
+     */
+    function onMessageReceive(string calldata sourceChain, string calldata sourceAddress, bytes calldata data)
+        external;
 
     /**
      * @notice Initiate sending a mapToken message to the child chain.
@@ -64,6 +72,14 @@ interface IRootERC20BridgeEvents {
         address indexed receiver,
         uint256 amount
     );
+
+    event RootChainERC20Withdraw(
+        address indexed rootToken,
+        address indexed childToken,
+        address withdrawer,
+        address indexed receiver,
+        uint256 amount
+    );
 }
 
 interface IRootERC20BridgeErrors {
@@ -73,6 +89,8 @@ interface IRootERC20BridgeErrors {
     error ZeroAmount();
     /// @notice Error when a zero address is given when not valid.
     error ZeroAddress();
+    /// @notice Error when the child chain name is invalid.
+    error InvalidChildChain();
     /// @notice Error when a token is already mapped.
     error AlreadyMapped();
     /// @notice Error when a token is not mapped when it should be.
@@ -87,6 +105,14 @@ interface IRootERC20BridgeErrors {
     error BalanceInvariantCheckFailed(uint256 actualBalance, uint256 expectedBalance);
     /// @notice Error when the given child chain bridge adaptor is invalid.
     error InvalidChildERC20BridgeAdaptor();
+    /// @notice Error when a message received has invalid data.
+    error InvalidData(string reason);
+    /// @notice Error when a message received has invalid source address.
+    error InvalidSourceAddress();
+    /// @notice Error when a message received has invalid source chain.
+    error InvalidSourceChain();
+    /// @notice Error when caller is not the root bridge adaptor but should be.
+    error NotBridgeAdaptor();
     /// @notice Error when the total IMX deposit limit is exceeded
     error ImxDepositLimitExceeded();
     /// @notice Error when the IMX deposit limit is set below the amount of IMX already deposited

src/root/RootAxelarBridgeAdaptor.sol

@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: Apache 2.0
 pragma solidity ^0.8.21;
 
+import {AxelarExecutable} from "@axelar-gmp-sdk-solidity/contracts/executable/AxelarExecutable.sol";
 import {Initializable} from "@openzeppelin/contracts/proxy/utils/Initializable.sol";
 import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
 import {IERC20Metadata} from "@openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol";
@@ -20,41 +21,38 @@ import {IRootERC20Bridge} from "../interfaces/root/IRootERC20Bridge.sol";
  * @notice RootAxelarBridgeAdaptor is a bridge adaptor that allows the RootERC20Bridge to communicate with the Axelar Gateway.
  */
 contract RootAxelarBridgeAdaptor is
+    AxelarExecutable,
     Initializable,
     IRootERC20BridgeAdaptor,
     IRootAxelarBridgeAdaptorEvents,
     IRootAxelarBridgeAdaptorErrors
 {
     using SafeERC20 for IERC20Metadata;
 
-    address public rootBridge;
+    IRootERC20Bridge public rootBridge;
     string public childBridgeAdaptor;
     string public childChain;
-    IAxelarGateway public axelarGateway;
     IAxelarGasService public gasService;
     mapping(uint256 => string) public chainIdToChainName;
 
+    constructor(address _gateway) AxelarExecutable(_gateway) {}
+
     /**
      * @notice Initilization function for RootAxelarBridgeAdaptor.
      * @param _rootBridge Address of root bridge contract.
      * @param _childChain Name of child chain.
-     * @param _axelarGateway Address of Axelar Gateway contract.
      * @param _gasService Address of Axelar Gas Service contract.
      */
-    function initialize(address _rootBridge, string memory _childChain, address _axelarGateway, address _gasService)
-        public
-        initializer
-    {
-        if (_rootBridge == address(0) || _axelarGateway == address(0) || _gasService == address(0)) {
+    function initialize(address _rootBridge, string memory _childChain, address _gasService) public initializer {
+        if (_rootBridge == address(0) || _gasService == address(0)) {
             revert ZeroAddresses();
         }
 
         if (bytes(_childChain).length == 0) {
             revert InvalidChildChain();
         }
-        rootBridge = _rootBridge;
+        rootBridge = IRootERC20Bridge(_rootBridge);
         childChain = _childChain;
-        axelarGateway = IAxelarGateway(_axelarGateway);
         gasService = IAxelarGasService(_gasService);
     }
 
@@ -66,7 +64,7 @@ contract RootAxelarBridgeAdaptor is
         if (msg.value == 0) {
             revert NoGas();
         }
-        if (msg.sender != rootBridge) {
+        if (msg.sender != address(rootBridge)) {
             revert CallerNotBridge();
         }
 
@@ -79,7 +77,18 @@ contract RootAxelarBridgeAdaptor is
             address(this), _childChain, _childBridgeAdaptor, payload, refundRecipient
         );
 
-        axelarGateway.callContract(_childChain, _childBridgeAdaptor, payload);
-        emit AxelarMessage(_childChain, _childBridgeAdaptor, payload);
+        gateway.callContract(_childChain, _childBridgeAdaptor, payload);
+        emit AxelarMessageSent(_childChain, _childBridgeAdaptor, payload);
+    }
+
+    /**
+     * @dev This function is called by the parent `AxelarExecutable` contract to execute the payload.
+     */
+    function _execute(string calldata sourceChain_, string calldata sourceAddress_, bytes calldata payload_)
+        internal
+        override
+    {
+        emit AdaptorExecute(sourceChain_, sourceAddress_, payload_);
+        rootBridge.onMessageReceive(sourceChain_, sourceAddress_, payload_);
     }
 }