fix: incorrect verifications

Author: jaybuidl

contracts/src/bridge/FastBridgeReceiverOnEthereum.sol

@@ -106,15 +106,10 @@ contract FastBridgeReceiverOnEthereum is SafeBridgeReceiverOnEthereum, IFastBrid
         emit ClaimChallenged(_ticketID, ticket.claim.messageHash, block.timestamp);
     }
 
-    function verifyAndRelay(
-        uint256 _ticketID,
-        bytes32 _messageHash,
-        bytes memory _messageData
-    ) external override {
-        require(_verify(_messageHash, _ticketID, _messageData), "Invalid hash");
-
+    function verifyAndRelay(uint256 _ticketID, bytes memory _messageData) external override {
         Ticket storage ticket = tickets[_ticketID];
         require(ticket.claim.bridger != address(0), "Claim does not exist");
+        require(ticket.claim.messageHash == keccak256(abi.encode(_ticketID, _messageData)), "Invalid hash");
         require(ticket.claim.claimedAt + challengeDuration < block.timestamp, "Challenge period not over");
         require(ticket.challenge.challenger == address(0), "Claim is challenged");
         require(ticket.relayed == false, "Message already relayed");
@@ -124,19 +119,15 @@ contract FastBridgeReceiverOnEthereum is SafeBridgeReceiverOnEthereum, IFastBrid
         require(_relay(_messageData), "Failed to call contract"); // Checks-Effects-Interaction
     }
 
-    function verifyAndRelaySafe(
-        uint256 _ticketID,
-        bytes32 _messageHash,
-        bytes memory _messageData
-    ) external override {
+    function verifyAndRelaySafe(uint256 _ticketID, bytes memory _messageData) external override {
         require(isSentBySafeBridge(), "Access not allowed: SafeBridgeSender only.");
-        require(_verify(_messageHash, _ticketID, _messageData), "Invalid hash");
 
         Ticket storage ticket = tickets[_ticketID];
         require(ticket.relayed == false, "Message already relayed");
 
         // Claim assessment if any
-        if (ticket.claim.bridger != address(0) && ticket.claim.messageHash == _messageHash) {
+        bytes32 messageHash = keccak256(abi.encode(_ticketID, _messageData));
+        if (ticket.claim.bridger != address(0) && ticket.claim.messageHash == messageHash) {
             ticket.claim.verified = true;
         }
 
@@ -203,14 +194,6 @@ contract FastBridgeReceiverOnEthereum is SafeBridgeReceiverOnEthereum, IFastBrid
     // *       Internal       * //
     // ************************ //
 
-    function _verify(
-        bytes32 _expectedHash,
-        uint256 _ticketID,
-        bytes memory _messageData
-    ) internal pure returns (bool) {
-        return _expectedHash == keccak256(abi.encode(_ticketID, _messageData));
-    }
-
     function _relay(bytes memory _messageData) internal returns (bool success) {
         // Decode the receiver address from the data encoded by the IFastBridgeSender
         (address receiver, bytes memory data) = abi.decode(_messageData, (address, bytes));

contracts/src/bridge/FastBridgeSenderToEthereum.sol

@@ -19,6 +19,15 @@ import "./interfaces/IFastBridgeReceiver.sol";
  * Counterpart of `FastBridgeReceiverOnEthereum`
  */
 contract FastBridgeSenderToEthereum is SafeBridgeSenderToEthereum, IFastBridgeSender {
+    // ************************************* //
+    // *         Enums / Structs           * //
+    // ************************************* //
+
+    struct Ticket {
+        bytes32 messageHash;
+        bool sentSafe;
+    }
+
     // ************************************* //
     // *             Storage               * //
     // ************************************* //
@@ -27,6 +36,7 @@ contract FastBridgeSenderToEthereum is SafeBridgeSenderToEthereum, IFastBridgeSe
     IFastBridgeReceiver public fastBridgeReceiver;
     address public fastSender;
     uint256 public currentTicketID = 1; // Zero means not set, start at 1.
+    mapping(uint256 => Ticket) public tickets; // The tickets by ticketID.
 
     // ************************************* //
     // *              Events               * //
@@ -68,8 +78,11 @@ contract FastBridgeSenderToEthereum is SafeBridgeSenderToEthereum, IFastBridgeSe
         require(msg.sender == fastSender, "Access not allowed: Fast Sender only.");
 
         ticketID = currentTicketID++;
+
         (bytes32 messageHash, bytes memory messageData) = _encode(ticketID, _receiver, _calldata);
         emit OutgoingMessage(ticketID, _receiver, messageHash, messageData);
+
+        tickets[ticketID] = Ticket({messageHash: messageHash, sentSafe: false});
     }
 
     /**
@@ -90,11 +103,16 @@ contract FastBridgeSenderToEthereum is SafeBridgeSenderToEthereum, IFastBridgeSe
         address _receiver,
         bytes memory _calldata
     ) external payable override {
+        Ticket storage ticket = tickets[_ticketID];
+        require(ticket.messageHash != 0, "Ticket does not exist.");
+        require(ticket.sentSafe == false, "Ticket already sent safely.");
+
         (bytes32 messageHash, bytes memory messageData) = _encode(_ticketID, _receiver, _calldata);
+        require(ticket.messageHash == messageHash, "Invalid message for ticketID.");
 
         // Safe Bridge message envelope
         bytes4 methodSelector = IFastBridgeReceiver.verifyAndRelaySafe.selector;
-        bytes memory safeMessageData = abi.encodeWithSelector(methodSelector, _ticketID, messageHash, messageData);
+        bytes memory safeMessageData = abi.encodeWithSelector(methodSelector, _ticketID, messageData);
 
         // TODO: how much ETH should be provided for bridging? add an ISafeBridgeSender.bridgingCost() if needed
         _sendSafe(address(fastBridgeReceiver), safeMessageData);

contracts/src/bridge/interfaces/IFastBridgeReceiver.sol

@@ -7,17 +7,9 @@ interface IFastBridgeReceiver {
 
     function challenge(uint256 _ticketID) external payable;
 
-    function verifyAndRelay(
-        uint256 _ticketID,
-        bytes32 _messageHash,
-        bytes memory _messageData
-    ) external;
-
-    function verifyAndRelaySafe(
-        uint256 _ticketID,
-        bytes32 _messageHash,
-        bytes memory _messageData
-    ) external;
+    function verifyAndRelay(uint256 _ticketID, bytes memory _messageData) external;
+
+    function verifyAndRelaySafe(uint256 _ticketID, bytes memory _messageData) external;
 
     function withdrawClaimDeposit(uint256 _ticketID) external;
 

contracts/src/bridge/interfaces/IFastBridgeSender.sol

@@ -16,6 +16,7 @@ interface IFastBridgeSender {
      * Sends an arbitrary message from one domain to another
      * via the fast bridge mechanism
      *
+     * @param _ticketID The identifier to provide to sendSafeFallback()
      * @param _receiver The L1 contract address who will receive the calldata
      * @param _calldata The receiving domain encoded message data.
      */