feat: implement L2ETHBridge.bridgeETH and L1ETHBridge.completeBridge

contracts/src/bridging/eth/L1ETHBridge.sol

@@ -4,18 +4,37 @@ pragma solidity ^0.8.30;
 import { Initializable } from "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
 import { UUPSUpgradeable } from "@openzeppelin/contracts-upgradeable/proxy/utils/UUPSUpgradeable.sol";
 import { OwnableUpgradeable } from "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
-
+import { ReentrancyGuardUpgradeable } from "@openzeppelin/contracts-upgradeable/security/ReentrancyGuardUpgradeable.sol";
 import { IL1ETHBridge } from "./interfaces/IL1ETHBridge.sol";
 import { IL2ETHBridge } from "./interfaces/IL2ETHBridge.sol";
 import { MessageServiceBase } from "../../messaging/MessageServiceBase.sol";
 import { IMessageService } from "../../messaging/interfaces/IMessageService.sol";
 
-contract L1ETHBridge is IL1ETHBridge, Initializable, UUPSUpgradeable, OwnableUpgradeable, MessageServiceBase {
+contract L1ETHBridge is IL1ETHBridge, Initializable, UUPSUpgradeable, OwnableUpgradeable, ReentrancyGuardUpgradeable, MessageServiceBase {
+  /**
+   * @notice The completed message struct.
+   */
+  struct CompletedMessage {
+    address to;
+    uint256 value;
+    bytes callData;
+  }
+
   /**
    * @notice The yield manager address.
    */
   address public yieldManager;
 
+  /**
+   * @notice The next completed message id.
+   */
+  uint256 public nextCompletedMessageId;
+
+  /**
+   * @notice The completed messages.
+   */
+  mapping(uint256 => CompletedMessage) public completedMessages;  
+
   /**
    * @dev Ensures the address is not address(0).
    * @param _addr Address to check.
@@ -87,6 +106,23 @@ contract L1ETHBridge is IL1ETHBridge, Initializable, UUPSUpgradeable, OwnableUpg
     yieldManager = _yieldManager;
   }
 
+  /**
+   * @notice Completes the bridge. Callable only by the L1MessageService.
+   * @param _to The recipient address.
+   * @param _value The amount of ETH to transfer.
+   * @param _calldata The calldata to pass to the recipient.
+   */
+  function completeBridge(
+    address _to,
+    uint256 _value,
+    bytes memory _calldata
+  ) external nonReentrant onlyMessagingService onlyAuthorizedRemoteSender {
+    completedMessages[nextCompletedMessageId] = CompletedMessage(_to, _value, _calldata);
+    nextCompletedMessageId++;
+
+    emit MessageCompleted(nextCompletedMessageId);
+  }
+
   /**
    * @notice Bridges ETH to the L2ETHBridge.
    * @param _to The recipient address on the L2.

contracts/src/bridging/eth/L2ETHBridge.sol

@@ -20,6 +20,15 @@ contract L2ETHBridge is IL2ETHBridge, Initializable, UUPSUpgradeable, OwnableUpg
     _;
   }
 
+  /**
+   * @dev Ensures the amount is not 0.
+   * @param _amount amount to check.
+   */
+  modifier nonZeroAmount(uint256 _amount) {
+    if (_amount == 0) revert L2ETHBridge__ZeroValueNotAllowed();
+    _;
+  }
+
   /**
    * @notice Disables initializers to prevent reinitialization.
    */
@@ -75,6 +84,19 @@ contract L2ETHBridge is IL2ETHBridge, Initializable, UUPSUpgradeable, OwnableUpg
     }
   }
 
+  /**
+   * @notice Bridges ETH to the L1ETHBridge.
+   * @param _to The recipient address on the L1.
+   * @param _calldata The calldata to be sent to the L1ETHBridge.
+   */
+  function bridgeETH(
+    address _to,
+    bytes memory _calldata
+  ) external payable nonZeroAmount(msg.value) nonZeroAddress(_to) {
+    bytes memory data = abi.encodeWithSelector(IL2ETHBridge.completeBridge.selector, _to, msg.value, _calldata);
+    messageService.sendMessage(remoteSender, 0, data);
+  }
+
   function _authorizeUpgrade(address) internal view override {
     _checkOwner();
   }

contracts/src/bridging/eth/interfaces/IL1ETHBridge.sol

@@ -14,6 +14,10 @@ interface IL1ETHBridge {
     address indexed setBy
   );
 
+  event MessageCompleted(
+    uint256 indexed messageId
+  );
+
   /**
    * @notice Emitted when the yield manager address is set.
    * @param newYieldManager The indexed new yield manager address.
@@ -28,6 +32,7 @@ interface IL1ETHBridge {
 
   error L1ETHBridge__ZeroValueNotAllowed();
   error L1ETHBridge__ZeroAddressNotAllowed();
+  error L1ETHBridge__ETHTransferFailed();
   error L1ETHBridge__YieldManagerDepositFailed();
 
   function setRemoteSender(address _remoteSender) external;
@@ -37,4 +42,6 @@ interface IL1ETHBridge {
   function setYieldManager(address _yieldManager) external;
 
   function bridgeETH(address _to, bytes memory _calldata) external payable;
+
+  function completeBridge(address _to, uint256 _value, bytes calldata _calldata) external;
 }

contracts/src/bridging/eth/interfaces/IL2ETHBridge.sol

@@ -14,9 +14,9 @@ interface IL2ETHBridge {
     address indexed setBy
   );
 
-  error L2ETHBridge__ETHTransferFailed();
-
+  error L2ETHBridge__ZeroValueNotAllowed();
   error L2ETHBridge__ZeroAddressNotAllowed();
+  error L2ETHBridge__ETHTransferFailed();
 
   function setRemoteSender(address _remoteSender) external;
 

contracts/test/foundry/bridging/eth/L1ETHBridge.t.sol

@@ -127,4 +127,31 @@ contract L1ETHBridgeTest is Test {
     assertEq(message.value, 0);
     assertEq(message.data, expectedData);
   }
+
+  function test_CompleteBridgeRevertsIfMsgSenderIsNotL2MessageService() public {
+    vm.prank(nonAuthorizedSender);
+    vm.expectRevert("CallerIsNotMessageService()");
+    bridge.completeBridge(user1, 0, "");
+  }
+
+  function test_CompleteBridgeRevertsIfRemoteSenderIsNotL2ETHBridge() public {
+    messageService.setOriginalSender(nonAuthorizedSender);
+    vm.prank(address(messageService));
+    vm.expectRevert("SenderNotAuthorized()");
+    bridge.completeBridge(user1, 0, "");
+  }
+
+  function test_CompleteBridge() public {
+    assertEq(bridge.nextCompletedMessageId(), 0);
+    messageService.setOriginalSender(remoteSender);
+
+    vm.prank(address(messageService));
+    bridge.completeBridge(user1, 100, "test-data");
+
+    assertEq(bridge.nextCompletedMessageId(), 1);
+    (address to, uint256 value, bytes memory callData) = bridge.completedMessages(0);
+    assertEq(to, user1);
+    assertEq(value, 100);
+    assertEq(callData, "test-data");
+  }
 }

contracts/test/foundry/bridging/eth/L2ETHBridge.t.sol

@@ -6,12 +6,15 @@ import { L2ETHBridge } from "../../../../src/bridging/eth/L2ETHBridge.sol";
 import { DeployL2ETHBridge } from "../../../../scripts/yield/bridge/l2/DeployL2ETHBridge.s.sol";
 import { RecipientMock } from "./mocks/RecipientMock.sol";
 import { L2MessageServiceMock } from "./mocks/L2MessageServiceMock.sol";
+import { IL1ETHBridge } from "../../../../src/bridging/eth/interfaces/IL1ETHBridge.sol";
 
 contract L2ETHBridgeTest is Test {
   L2ETHBridge bridge;
 
   address deployer;
   address l1ETHBridge;
+  address user1 = makeAddr("user1");
+  address user2 = makeAddr("user2");
   address nonAuthorizedSender = makeAddr("nonAuthorizedSender");
   L2MessageServiceMock l2MessageService;
 
@@ -66,8 +69,6 @@ contract L2ETHBridgeTest is Test {
   }
 
   function test_CompleteBridgeRevertsIfMsgSenderIsNotL2MessageService() public {
-    l2MessageService.setOriginalSender(l1ETHBridge);
-
     vm.prank(nonAuthorizedSender);
     vm.expectRevert("CallerIsNotMessageService()");
     bridge.completeBridge(l1ETHBridge, 0, "");
@@ -78,7 +79,7 @@ contract L2ETHBridgeTest is Test {
 
     vm.prank(address(l2MessageService));
     vm.expectRevert("SenderNotAuthorized()");
-    bridge.completeBridge(nonAuthorizedSender, 0, "");
+    bridge.completeBridge(user1, 0, "");
   }
 
   function test_CompleteBridge() public {
@@ -94,4 +95,35 @@ contract L2ETHBridgeTest is Test {
     assertEq(recipientMock.lastCallParam(), 77);
     assertEq(address(recipientMock).balance, 100);
   }
+
+  function test_bridgeETHRevertsIfValueIsZero() public {
+    vm.expectRevert("L2ETHBridge__ZeroValueNotAllowed()");
+    bridge.bridgeETH(address(recipientMock), "");
+  }
+
+  function test_bridgeETHRevertsIfToIsZeroAddress() public {
+    vm.expectRevert("L2ETHBridge__ZeroAddressNotAllowed()");
+    bridge.bridgeETH{value: 100}(address(0), "");
+  }
+
+  function test_ETHBridgeMessagesAreSentToL1ETHBridge() public {
+    vm.deal(user1, 100);
+    vm.prank(user1);
+    bridge.bridgeETH{ value: 100 }(user2, "test-message");
+
+    assertEq(l2MessageService.messagesLength(), 1);
+
+    bytes memory expectedData = abi.encodeWithSelector(
+      IL1ETHBridge.completeBridge.selector,
+      user2,
+      100,
+      "test-message"
+    );
+
+    L2MessageServiceMock.Message memory message = l2MessageService.lastMessage();
+    assertEq(message.to, l1ETHBridge);
+    assertEq(message.fee, 0);
+    assertEq(message.value, 0);
+    assertEq(message.data, expectedData);
+  }
 }

contracts/test/foundry/bridging/eth/mocks/L2MessageServiceMock.sol

@@ -2,6 +2,15 @@
 pragma solidity ^0.8.30;
 
 contract L2MessageServiceMock {
+  struct Message {
+    address to;
+    uint256 fee;
+    uint256 value;
+    bytes data;
+  }
+
+  Message[] public messages;
+
   address public originalSender;
 
   function setOriginalSender(address _originalSender) external {
@@ -11,4 +20,17 @@ contract L2MessageServiceMock {
   function sender() external view returns (address) {
     return originalSender;
   }
+
+  function sendMessage(address _to, uint256 _fee, bytes calldata _calldata) external payable {
+    messages.push(Message({ to: _to, fee: _fee, value: msg.value, data: _calldata }));
+  }
+
+  function messagesLength() external view returns (uint256) {
+    return messages.length;
+  }
+
+  function lastMessage() external view returns (Message memory) {
+    require(messages.length > 0, "No messages made");
+    return messages[messages.length - 1];
+  }
 }

contracts/test/foundry/bridging/eth/mocks/RollupMock.sol

@@ -11,6 +11,16 @@ contract RollupMock {
 
   Message[] public messages;
 
+  address public originalSender;
+
+  function setOriginalSender(address _originalSender) external {
+    originalSender = _originalSender;
+  }
+
+  function sender() external view returns (address) {
+    return originalSender;
+  }
+
   function sendMessage(address _to, uint256 _fee, bytes calldata _calldata) external payable {
     messages.push(Message({ to: _to, fee: _fee, value: msg.value, data: _calldata }));
   }