evm: CCTPv2 support

Author: bruce-riley

evm/README.md

@@ -94,6 +94,28 @@ executor.requestExecution{value: executorArgs.value}(
 
 <!-- cspell:enable -->
 
+#### Example v2 CCTP Request
+
+<!-- cspell:disable -->
+
+```solidity
+import "example-messaging-executor/evm/src/interfaces/IExecutor.sol";
+import "example-messaging-executor/evm/src/libraries/ExecutorMessages.sol";
+...
+uint64 nonce = circleTokenMessenger.depositForBurn(amount, destinationDomain, mintRecipient, burnToken, destinationCaller, maxFee, minFinalityThreshold);
+
+executor.requestExecution{value: executorArgs.value}(
+    0,
+    bytes32(0),
+    executorArgs.refundAddress,
+    executorArgs.signedQuote,
+    ExecutorMessages.makeCCTPv2Request(sourceDomain, nonce),
+    executorArgs.instructions
+);
+```
+
+<!-- cspell:enable -->
+
 ### Execution Support
 
 #### v1 VAA Execution
@@ -120,6 +142,14 @@ The Circle Message Transmitter contract implements the following function.
 function receiveMessage(bytes calldata message,bytes calldata attestation) external override whenNotPaused returns (bool success)
 ```
 
+#### v2 CCTP Execution
+
+The Circle Message Transmitter contract implements the following function.
+
+```solidity
+function receiveMessage(bytes calldata message,bytes calldata attestation) external override whenNotPaused returns (bool success)
+```
+
 ## Executor Development
 
 ### Testing

evm/src/libraries/ExecutorMessages.sol

@@ -6,6 +6,7 @@ library ExecutorMessages {
     bytes4 private constant REQ_VAA_V1 = "ERV1";
     bytes4 private constant REQ_NTT_V1 = "ERN1";
     bytes4 private constant REQ_CCTP_V1 = "ERC1";
+    bytes4 private constant REQ_CCTP_V2 = "ERC2";
 
     /// @notice Payload length will not fit in a uint32.
     /// @dev Selector: 492f620d.
@@ -63,4 +64,12 @@ library ExecutorMessages {
     function makeCCTPv1Request(uint32 sourceDomain, uint64 nonce) internal pure returns (bytes memory) {
         return abi.encodePacked(REQ_CCTP_V1, sourceDomain, nonce);
     }
+
+    /// @notice Encodes a version 2 CCTP request payload.
+    /// @param sourceDomain The source chain for the CCTP transfer.
+    /// @param nonce The nonce of the CCTP transfer.
+    /// @return bytes The encoded request.
+    function makeCCTPv2Request(uint32 sourceDomain, uint64 nonce) internal pure returns (bytes memory) {
+        return abi.encodePacked(REQ_CCTP_V2, sourceDomain, nonce);
+    }
 }

evm/test/ExecutorMessages.t.sol

@@ -46,4 +46,12 @@ contract ExecutorMessagesTest is Test {
         bytes memory buf = ExecutorMessages.makeCCTPv1Request(srcDomain, nonce);
         assertEq(keccak256(expected), keccak256(buf));
     }
+
+    function test_makeCCTPv2Request() public pure {
+        uint32 srcDomain = 7;
+        uint64 nonce = 42;
+        bytes memory expected = abi.encodePacked("ERC2", srcDomain, nonce);
+        bytes memory buf = ExecutorMessages.makeCCTPv2Request(srcDomain, nonce);
+        assertEq(keccak256(expected), keccak256(buf));
+    }
 }