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External Chain Address Management

The Treasury Host Chain Station uses a time-delayed proposal system to configure external chain station addresses for all supported cross-chain protocols. This administrative governance ensures secure management of cross-chain connections.

proposeExternalChainAddress​

Function Type: external
Function Signature: proposeExternalChainAddress(address,string)
Access Control: onlyAdmin
Returns: void

Proposes new external chain station addresses for all protocols with a mandatory time delay (typically 1 day) for security.

Parameters​

ParameterTypeDescription
externalChainStationAddressaddressExternal station address for Hyperlane and LayerZero
externalChainStationAddressStringstringExternal station address for Axelar (string format)

Workflow​

  1. One-Time Check: Validates fuseSetExternalChainAddress != 0x01 to ensure this is not initial setup
  2. Proposal Setup: Creates ChangeExternalChainAddressParams with both address formats
  3. Time Lock: Sets timeToAccept = block.timestamp + 1 day (or configured delay)
externalChainAddressChangeProposal = ChangeExternalChainAddressParams({
    porposeAddress_AddressType: externalChainStationAddress,
    porposeAddress_StringType: externalChainStationAddressString,
    timeToAccept: block.timestamp + 1 minutes
});

rejectProposalExternalChainAddress​

Function Type: external
Function Signature: rejectProposalExternalChainAddress()
Access Control: onlyAdmin
Returns: void

Cancels a pending external chain address change proposal.

Workflow​

Resets the proposal to default state:

externalChainAddressChangeProposal = ChangeExternalChainAddressParams({
    porposeAddress_AddressType: address(0),
    porposeAddress_StringType: "",
    timeToAccept: 0
});

acceptExternalChainAddress​

Function Type: external
Function Signature: acceptExternalChainAddress()
Access Control: public (anyone can execute after time delay)
Returns: void

Accepts pending external chain address changes and updates all protocol configurations.

Workflow​

  1. Time Validation: Ensures block.timestamp >= externalChainAddressChangeProposal.timeToAccept
  2. Hyperlane Update: Converts address to bytes32 and sets hyperlane.externalChainStationAddress
  3. LayerZero Update: Converts address to bytes32 and sets layerZero.externalChainStationAddress
  4. Axelar Update: Sets axelar.externalChainStationAddress using string format
  5. Peer Setup: Calls _setPeer() to establish LayerZero peer relationship

Governance Workflow​

The complete process for changing external chain addresses:

  1. Propose: Admin calls proposeExternalChainAddress() with new addresses
  2. Wait: Mandatory time delay (typically 1 day) for security review
  3. Accept or Reject:
    • Anyone can call acceptExternalChainAddress() after delay
    • Admin can call rejectProposalExternalChainAddress() to cancel

Protocol-Specific Address Formats​

Hyperlane & LayerZero​

  • Input Format: address
  • Stored Format: bytes32 (converted internally)
  • Usage: Direct address representation for protocol routing

Axelar​

  • Format: string
  • Usage: Human-readable address for Axelar gateway calls
  • Example: "0x742d35Cc6634C0532925a3b8D43C1C16bE8c9123"

Security Considerations​

Time-Delayed Governance​

  • Proposal Period: 1-day delay provides time for community review
  • Cancellation: Admin can reject proposals before acceptance
  • Public Execution: Anyone can execute after delay expires

Address Validation​

  • Critical Setup: Incorrect addresses will break cross-chain communication
  • Format Consistency: Both address and string parameters must represent the same contract
  • One-Time Fuse: fuseSetExternalChainAddress prevents certain re-configurations

Usage Example​

// Step 1: Propose new external chain address
proposeExternalChainAddress(
    0x742d35Cc6634C0532925a3b8D43C1C16bE8c9123, // address format
    "0x742d35Cc6634C0532925a3b8D43C1C16bE8c9123"  // string format
);

// Step 2: Wait for time delay (1 day)
// ...

// Step 3: Accept the proposal
acceptExternalChainAddress();
Critical Configuration

This system establishes the foundation for all cross-chain communication. Incorrect addresses will result in failed transfers and potential loss of funds. Always verify external station deployment and address accuracy before proposing changes.