feat: add merkle sigs natively into the account

ithacaxyz · Dargon789 · Sep 24, 2025 · Sep 24, 2025 · Sep 24, 2025 · Sep 24, 2025
commit 2ecce316b8bad62c40f31a5ceeb500726d926d1c
diff --git a/snapshots/BenchmarkTest.json b/snapshots/BenchmarkTest.json
@@ -16,11 +16,11 @@
   "testERC20Transfer_ERC4337MinimalAccount": "171509",
   "testERC20Transfer_ERC4337MinimalAccount_AppSponsor": "168500",
   "testERC20Transfer_ERC4337MinimalAccount_ERC20SelfPay": "199831",
-  "testERC20Transfer_IthacaAccount": "128059",
-  "testERC20Transfer_IthacaAccountWithSpendLimits": "193602",
-  "testERC20Transfer_IthacaAccount_AppSponsor": "138595",
-  "testERC20Transfer_IthacaAccount_AppSponsor_ERC20": "143884",
-  "testERC20Transfer_IthacaAccount_ERC20SelfPay": "128548",
+  "testERC20Transfer_IthacaAccount": "128100",
+  "testERC20Transfer_IthacaAccountWithSpendLimits": "193589",
+  "testERC20Transfer_IthacaAccount_AppSponsor": "138636",
+  "testERC20Transfer_IthacaAccount_AppSponsor_ERC20": "143937",
+  "testERC20Transfer_IthacaAccount_ERC20SelfPay": "128589",
   "testERC20Transfer_Safe4337": "197561",
   "testERC20Transfer_Safe4337_AppSponsor": "191725",
   "testERC20Transfer_Safe4337_ERC20SelfPay": "221464",
@@ -29,25 +29,25 @@
   "testERC20Transfer_ZerodevKernel_ERC20SelfPay": "235489",
   "testERC20Transfer_batch100_AlchemyModularAccount": "10109066",
   "testERC20Transfer_batch100_AlchemyModularAccount_ERC20SelfPay": "11609298",
-  "testERC20Transfer_batch100_IthacaAccount": "7531912",
-  "testERC20Transfer_batch100_IthacaAccount_AppSponsor": "8140216",
-  "testERC20Transfer_batch100_IthacaAccount_AppSponsor_ERC20": "7966120",
-  "testERC20Transfer_batch100_IthacaAccount_ERC20SelfPay": "7353064",
+  "testERC20Transfer_batch100_IthacaAccount": "7535892",
+  "testERC20Transfer_batch100_IthacaAccount_AppSponsor": "8144196",
+  "testERC20Transfer_batch100_IthacaAccount_AppSponsor_ERC20": "7970208",
+  "testERC20Transfer_batch100_IthacaAccount_ERC20SelfPay": "7357152",
   "testERC20Transfer_batch100_ZerodevKernel": "12631318",
   "testERC20Transfer_batch100_ZerodevKernel_ERC20SelfPay": "14149937",
   "testNativeTransfer_AlchemyModularAccount": "180829",
   "testNativeTransfer_CoinbaseSmartWallet": "178916",
-  "testNativeTransfer_IthacaAccount": "129415",
-  "testNativeTransfer_IthacaAccount_AppSponsor": "139982",
-  "testNativeTransfer_IthacaAccount_ERC20SelfPay": "137204",
+  "testNativeTransfer_IthacaAccount": "129456",
+  "testNativeTransfer_IthacaAccount_AppSponsor": "140023",
+  "testNativeTransfer_IthacaAccount_ERC20SelfPay": "137245",
   "testNativeTransfer_Safe4337": "198595",
   "testNativeTransfer_ZerodevKernel": "208635",
   "testUniswapV2Swap_AlchemyModularAccount": "238647",
   "testUniswapV2Swap_CoinbaseSmartWallet": "237451",
   "testUniswapV2Swap_ERC4337MinimalAccount": "230691",
-  "testUniswapV2Swap_IthacaAccount": "187179",
-  "testUniswapV2Swap_IthacaAccount_AppSponsor": "197691",
-  "testUniswapV2Swap_IthacaAccount_ERC20SelfPay": "192480",
+  "testUniswapV2Swap_IthacaAccount": "187244",
+  "testUniswapV2Swap_IthacaAccount_AppSponsor": "197744",
+  "testUniswapV2Swap_IthacaAccount_ERC20SelfPay": "192533",
   "testUniswapV2Swap_Safe4337": "257333",
   "testUniswapV2Swap_ZerodevKernel": "266367"
 }
diff --git a/src/IthacaAccount.sol b/src/IthacaAccount.sol
@@ -23,6 +23,7 @@ import {LibNonce} from "./libraries/LibNonce.sol";
 import {TokenTransferLib} from "./libraries/TokenTransferLib.sol";
 import {LibTStack} from "./libraries/LibTStack.sol";
 import {IIthacaAccount} from "./interfaces/IIthacaAccount.sol";
+import {MerkleProofLib} from "solady/utils/MerkleProofLib.sol";
 
 /// @title Account
 /// @notice A account contract for EOAs with EIP7702.
@@ -490,9 +491,52 @@ contract IthacaAccount is IIthacaAccount, EIP712, GuardedExecutor {
         return isMultichain ? _hashTypedDataSansChainId(structHash) : _hashTypedData(structHash);
     }
 
+    /// @dev Verifies the merkle sig for the multi chain intents.
+    /// - Note: Each leaf of the merkle tree should be a standard intent digest, computed with chainId.
+    /// - Leaf intents do NOT need to have the multichain nonce prefix.
+    /// - The signature for multi chain intents using merkle verification is encoded as:
+    /// - bytes signature = abi.encode(bytes32[] proof, bytes32 root, bytes rootSig)
+    function _verifyMerkleSig(bytes32 digest, bytes calldata signature)
+        internal
+        view
+        returns (bool isValid, bytes32 keyHash)
+    {
+        bytes32[] calldata proof;
+        bytes32 root;
+        bytes calldata rootSig;
+
+        assembly ("memory-safe") {
+            let proofOffset := add(signature.offset, calldataload(signature.offset))
+            proof.length := calldataload(proofOffset)
+            proof.offset := add(proofOffset, 0x20)
+
+            root := calldataload(add(signature.offset, 0x20))
+
+            let rootSigOffset := add(signature.offset, calldataload(add(signature.offset, 0x40)))
+            rootSig.length := calldataload(rootSigOffset)
+            rootSig.offset := add(rootSigOffset, 0x20)
+        }
+
+        console.logBytes32(root);
+
+        console.log("Proof length: ", proof.length);
+        console.logBytes32(proof[0]);
+
+        if (MerkleProofLib.verifyCalldata(proof, root, digest)) {
+            console.log("Entered here");
+            (isValid, keyHash) = unwrapAndValidateSignature(root, rootSig);
+
+            console.logBytes32(keyHash);
+            console.log(isValid);
+            return (isValid, keyHash);
+        }
+
+        return (false, bytes32(0));
+    }
+
     /// @dev Returns if the signature is valid, along with its `keyHash`.
     /// The `signature` is a wrapped signature, given by
-    /// `abi.encodePacked(bytes(innerSignature), bytes32(keyHash), bool(prehash))`.
+    /// `abi.encode(bytes(innerSignature), bytes32(keyHash), bool(prehash), bool(merkle))`.
     function unwrapAndValidateSignature(bytes32 digest, bytes calldata signature)
         public
         view
@@ -507,14 +551,25 @@ contract IthacaAccount is IIthacaAccount, EIP712, GuardedExecutor {
             return (ECDSA.recoverCalldata(digest, signature) == address(this), 0);
         }
 
+        bool merkle;
         unchecked {
-            uint256 n = signature.length - 0x21;
+            uint256 n = signature.length - 0x22;
             keyHash = LibBytes.loadCalldata(signature, n);
             signature = LibBytes.truncatedCalldata(signature, n);
             // Do the prehash if last byte is non-zero.
             if (uint256(LibBytes.loadCalldata(signature, n + 1)) & 0xff != 0) {
+                console.log("prehash");
                 digest = EfficientHashLib.sha2(digest); // `sha256(abi.encode(digest))`.
             }
+            merkle = uint256(LibBytes.loadCalldata(signature, n + 2)) & 0xff != 0;
+        }
+
+        console.logBytes(signature);
+
+        console.log("Reached here", merkle);
+        if (merkle) {
+            console.log("merkle");
+            return _verifyMerkleSig(digest, signature);
         }
 
         Key memory key = getKey(keyHash);