From 6c9056598b9bc78121c7e70acce51c4b8cf308ce Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Tue, 10 Dec 2024 16:02:00 +0200
Subject: [PATCH 01/16] Addressed ackee's report.

---
 contracts/InterchainTokenFactory.sol          |  2 +
 contracts/InterchainTokenService.sol          | 40 +++++++++----------
 contracts/TokenHandler.sol                    |  3 +-
 contracts/interchain-token/ERC20Permit.sol    | 10 +++++
 .../interchain-token/InterchainToken.sol      |  7 +---
 contracts/interfaces/IBaseTokenManager.sol    |  2 +
 .../interfaces/IInterchainTokenFactory.sol    |  3 +-
 .../interfaces/IInterchainTokenService.sol    |  1 -
 contracts/interfaces/ITokenManager.sol        |  8 +---
 .../interfaces/ITokenManagerDeployer.sol      |  1 -
 contracts/token-manager/TokenManager.sol      |  7 +++-
 .../types/InterchainTokenServiceTypes.sol     |  4 +-
 12 files changed, 47 insertions(+), 41 deletions(-)

diff --git a/contracts/InterchainTokenFactory.sol b/contracts/InterchainTokenFactory.sol
index f3be98d3..31b4422b 100644
--- a/contracts/InterchainTokenFactory.sol
+++ b/contracts/InterchainTokenFactory.sol
@@ -149,6 +149,8 @@ contract InterchainTokenFactory is IInterchainTokenFactory, ITokenManagerType, M
             if (minter == address(interchainTokenService)) revert InvalidMinter(minter);
 
             minterBytes = minter.toBytes();
+        } else {
+            revert EmptyInterchainToken();
         }
 
         tokenId = _deployInterchainToken(deploySalt, currentChain, name, symbol, decimals, minterBytes, gasValue);
diff --git a/contracts/InterchainTokenService.sol b/contracts/InterchainTokenService.sol
index 7c83b429..fff6d471 100644
--- a/contracts/InterchainTokenService.sol
+++ b/contracts/InterchainTokenService.sol
@@ -395,6 +395,26 @@ contract InterchainTokenService is
         return _contractCallValue(payload);
     }
 
+    /**
+     * @notice Executes operations based on the payload and selector.
+     * @param commandId The unique message id.
+     * @param sourceChain The chain where the transaction originates from.
+     * @param sourceAddress The address of the remote ITS where the transaction originates from.
+     * @param payload The encoded data payload for the transaction.
+     */
+    function execute(
+        bytes32 commandId,
+        string calldata sourceChain,
+        string calldata sourceAddress,
+        bytes calldata payload
+    ) external onlyRemoteService(sourceChain, sourceAddress) whenNotPaused {
+        bytes32 payloadHash = keccak256(payload);
+
+        if (!gateway.validateContractCall(commandId, sourceChain, sourceAddress, payloadHash)) revert NotApprovedByGateway();
+
+        _execute(commandId, sourceChain, sourceAddress, payload, payloadHash);
+    }
+
     /**
      * @notice Express executes operations based on the payload and selector.
      * @dev This function is `payable` because non-payable functions cannot be called in a multicall that calls other `payable` functions.
@@ -646,26 +666,6 @@ contract InterchainTokenService is
         }
     }
 
-    /**
-     * @notice Executes operations based on the payload and selector.
-     * @param commandId The unique message id.
-     * @param sourceChain The chain where the transaction originates from.
-     * @param sourceAddress The address of the remote ITS where the transaction originates from.
-     * @param payload The encoded data payload for the transaction.
-     */
-    function execute(
-        bytes32 commandId,
-        string calldata sourceChain,
-        string calldata sourceAddress,
-        bytes calldata payload
-    ) external onlyRemoteService(sourceChain, sourceAddress) whenNotPaused {
-        bytes32 payloadHash = keccak256(payload);
-
-        if (!gateway.validateContractCall(commandId, sourceChain, sourceAddress, payloadHash)) revert NotApprovedByGateway();
-
-        _execute(commandId, sourceChain, sourceAddress, payload, payloadHash);
-    }
-
     /**
      * @notice Processes the payload data for a send token call.
      * @param commandId The unique message id.
diff --git a/contracts/TokenHandler.sol b/contracts/TokenHandler.sol
index be794e9a..69932021 100644
--- a/contracts/TokenHandler.sol
+++ b/contracts/TokenHandler.sol
@@ -16,12 +16,11 @@ import { IERC20BurnableFrom } from './interfaces/IERC20BurnableFrom.sol';
 
 /**
  * @title TokenHandler
- * @notice This interface is responsible for handling tokens before initiating an interchain token transfer, or after receiving one.
+ * @notice This contract is responsible for handling tokens before initiating an interchain token transfer, or after receiving one.
  */
 contract TokenHandler is ITokenHandler, ITokenManagerType, ReentrancyGuard, Create3AddressFixed {
     using SafeTokenTransferFrom for IERC20;
     using SafeTokenCall for IERC20;
-    using SafeTokenTransfer for IERC20;
 
     /**
      * @notice This function gives token to a specified address from the token manager.
diff --git a/contracts/interchain-token/ERC20Permit.sol b/contracts/interchain-token/ERC20Permit.sol
index b692d723..00826284 100644
--- a/contracts/interchain-token/ERC20Permit.sol
+++ b/contracts/interchain-token/ERC20Permit.sol
@@ -23,6 +23,7 @@ abstract contract ERC20Permit is IERC20, IERC20Permit, ERC20 {
      */
     bytes32 public nameHash;
 
+    // Prefix for the EIP712 structured data.
     string private constant EIP191_PREFIX_FOR_EIP712_STRUCTURED_DATA = '\x19\x01';
 
     // keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)')
@@ -71,6 +72,15 @@ abstract contract ERC20Permit is IERC20, IERC20Permit, ERC20 {
     function permit(address issuer, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) external {
         if (block.timestamp > deadline) revert PermitExpired();
 
+        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
+        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
+        // the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
+        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
+        //
+        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
+        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
+        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
+        // these malleable signatures as well.
         if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) revert InvalidS();
 
         if (v != 27 && v != 28) revert InvalidV();
diff --git a/contracts/interchain-token/InterchainToken.sol b/contracts/interchain-token/InterchainToken.sol
index 1dea362a..03265886 100644
--- a/contracts/interchain-token/InterchainToken.sol
+++ b/contracts/interchain-token/InterchainToken.sol
@@ -2,12 +2,9 @@
 
 pragma solidity ^0.8.0;
 
-import { AddressBytes } from '@axelar-network/axelar-gmp-sdk-solidity/contracts/libs/AddressBytes.sol';
-
 import { IInterchainToken } from '../interfaces/IInterchainToken.sol';
 
 import { InterchainTokenStandard } from './InterchainTokenStandard.sol';
-import { ERC20 } from './ERC20.sol';
 import { ERC20Permit } from './ERC20Permit.sol';
 import { Minter } from '../utils/Minter.sol';
 
@@ -16,9 +13,7 @@ import { Minter } from '../utils/Minter.sol';
  * @notice This contract implements an interchain token which extends InterchainToken functionality.
  * @dev This contract also inherits Minter and Implementation logic.
  */
-contract InterchainToken is InterchainTokenStandard, ERC20, ERC20Permit, Minter, IInterchainToken {
-    using AddressBytes for bytes;
-
+contract InterchainToken is InterchainTokenStandard, ERC20Permit, Minter, IInterchainToken {
     string public name;
     string public symbol;
     uint8 public decimals;
diff --git a/contracts/interfaces/IBaseTokenManager.sol b/contracts/interfaces/IBaseTokenManager.sol
index 2ceff77d..b3dba446 100644
--- a/contracts/interfaces/IBaseTokenManager.sol
+++ b/contracts/interfaces/IBaseTokenManager.sol
@@ -9,12 +9,14 @@ pragma solidity ^0.8.0;
 interface IBaseTokenManager {
     /**
      * @notice A function that returns the token id.
+     * @dev This is stored in the proxy and should not be called in the implementation, but it is included here so that the interface properly tells us what functions exist.
      */
     function interchainTokenId() external view returns (bytes32);
 
     /**
      * @notice A function that should return the address of the token.
      * Must be overridden in the inheriting contract.
+     * @dev This is stored in the proxy and should not be called in the implementation, but it is included here so that the interface properly tells us what functions exist.
      * @return address address of the token.
      */
     function tokenAddress() external view returns (address);
diff --git a/contracts/interfaces/IInterchainTokenFactory.sol b/contracts/interfaces/IInterchainTokenFactory.sol
index e425ecbf..0db2aa76 100644
--- a/contracts/interfaces/IInterchainTokenFactory.sol
+++ b/contracts/interfaces/IInterchainTokenFactory.sol
@@ -16,11 +16,10 @@ interface IInterchainTokenFactory is IUpgradable, IMulticall {
     error InvalidChainName();
     error InvalidMinter(address minter);
     error NotMinter(address minter);
-    error NotOperator(address operator);
-    error NotServiceOwner(address sender);
     error NotSupported();
     error RemoteDeploymentNotApproved();
     error InvalidTokenId(bytes32 tokenId, bytes32 expectedTokenId);
+    error EmptyInterchainToken();
 
     /// @notice Emitted when a minter approves a deployer for a remote interchain token deployment that uses a custom destinationMinter address.
     event DeployRemoteInterchainTokenApproval(
diff --git a/contracts/interfaces/IInterchainTokenService.sol b/contracts/interfaces/IInterchainTokenService.sol
index b3f5fc12..f6aef9cd 100644
--- a/contracts/interfaces/IInterchainTokenService.sol
+++ b/contracts/interfaces/IInterchainTokenService.sol
@@ -29,7 +29,6 @@ interface IInterchainTokenService is
     IAddressTracker,
     IUpgradable
 {
-    error InvalidTokenManagerImplementationType(address implementation);
     error InvalidChainName();
     error NotRemoteService();
     error TokenManagerDoesNotExist(bytes32 tokenId);
diff --git a/contracts/interfaces/ITokenManager.sol b/contracts/interfaces/ITokenManager.sol
index 50c582a9..23c778b2 100644
--- a/contracts/interfaces/ITokenManager.sol
+++ b/contracts/interfaces/ITokenManager.sol
@@ -15,16 +15,12 @@ import { IFlowLimit } from './IFlowLimit.sol';
 interface ITokenManager is IBaseTokenManager, IOperator, IFlowLimit, IImplementation {
     error TokenLinkerZeroAddress();
     error NotService(address caller);
-    error TakeTokenFailed();
-    error GiveTokenFailed();
-    error NotToken(address caller);
-    error ZeroAddress();
-    error AlreadyFlowLimiter(address flowLimiter);
-    error NotFlowLimiter(address flowLimiter);
+    error ZeroTokenAddress();
     error NotSupported();
 
     /**
      * @notice Returns implementation type of this token manager.
+     * @dev This is stored in the proxy and should not be called in the implementation, but it is included here so that the interface properly tells us what functions exist.
      * @return uint256 The implementation type of this token manager.
      */
     function implementationType() external view returns (uint256);
diff --git a/contracts/interfaces/ITokenManagerDeployer.sol b/contracts/interfaces/ITokenManagerDeployer.sol
index 8e9acdd6..5478d0c1 100644
--- a/contracts/interfaces/ITokenManagerDeployer.sol
+++ b/contracts/interfaces/ITokenManagerDeployer.sol
@@ -7,7 +7,6 @@ pragma solidity ^0.8.0;
  * @notice This interface is used to deploy new instances of the TokenManagerProxy contract.
  */
 interface ITokenManagerDeployer {
-    error AddressZero();
     error TokenManagerDeploymentFailed();
 
     /**
diff --git a/contracts/token-manager/TokenManager.sol b/contracts/token-manager/TokenManager.sol
index e6d30174..dbcc61db 100644
--- a/contracts/token-manager/TokenManager.sol
+++ b/contracts/token-manager/TokenManager.sol
@@ -18,6 +18,7 @@ import { FlowLimit } from '../utils/FlowLimit.sol';
 /**
  * @title TokenManager
  * @notice This contract is responsible for managing tokens, such as setting locking token balances, or setting flow limits, for interchain transfers.
+ * @dev Should only be used as an implementation for TokenManagerProxy.
  */
 contract TokenManager is ITokenManager, Operator, FlowLimit, Implementation, Multicall {
     using AddressBytes for bytes;
@@ -57,8 +58,8 @@ contract TokenManager is ITokenManager, Operator, FlowLimit, Implementation, Mul
 
     /**
      * @notice Reads the token address from the proxy.
-     * @dev This function is not supported when directly called on the implementation. It
-     * must be called by the proxy.
+     * @dev This function is not supported when directly called on the implementation.
+     * It must be called by the proxy. It is included here so that the interace shows this function as existing, for better UX.
      * @return tokenAddress_ The address of the token.
      */
     function tokenAddress() external view virtual returns (address) {
@@ -68,6 +69,7 @@ contract TokenManager is ITokenManager, Operator, FlowLimit, Implementation, Mul
     /**
      * @notice A function that returns the token id.
      * @dev This will only work when implementation is called by a proxy, which stores the tokenId as an immutable.
+     * It is included here so that the interace shows this function as existing, for better UX.
      * @return bytes32 The interchain token ID.
      */
     function interchainTokenId() public pure returns (bytes32) {
@@ -89,6 +91,7 @@ contract TokenManager is ITokenManager, Operator, FlowLimit, Implementation, Mul
      */
     function getTokenAddressFromParams(bytes calldata params_) external pure returns (address tokenAddress_) {
         (, tokenAddress_) = abi.decode(params_, (bytes, address));
+        if (tokenAddress_ == address(0)) revert ZeroTokenAddress();
     }
 
     /**
diff --git a/contracts/types/InterchainTokenServiceTypes.sol b/contracts/types/InterchainTokenServiceTypes.sol
index 9e293028..89d886ef 100644
--- a/contracts/types/InterchainTokenServiceTypes.sol
+++ b/contracts/types/InterchainTokenServiceTypes.sol
@@ -5,7 +5,9 @@ pragma solidity ^0.8.0;
 enum MessageType {
     INTERCHAIN_TRANSFER,
     DEPLOY_INTERCHAIN_TOKEN,
-    DEPLOY_TOKEN_MANAGER
+    DEPLOY_TOKEN_MANAGER,
+    SEND_TO_HUB,
+    RECEIVE_FROM_HUB
 }
 
 struct InterchainTransfer {

From 9aef7679169e7c1f223642d8a09946707eb81897 Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Wed, 11 Dec 2024 17:43:52 +0200
Subject: [PATCH 02/16] fix all tests

---
 test/InterchainToken.js        |  2 +-
 test/InterchainTokenFactory.js | 17 ++++++-----------
 test/InterchainTokenService.js |  4 ++--
 test/TokenManager.js           |  2 +-
 4 files changed, 10 insertions(+), 15 deletions(-)

diff --git a/test/InterchainToken.js b/test/InterchainToken.js
index a7ff687a..300678c7 100644
--- a/test/InterchainToken.js
+++ b/test/InterchainToken.js
@@ -147,7 +147,7 @@ describe('InterchainToken', () => {
             const contractBytecodeHash = keccak256(contractBytecode);
 
             const expected = {
-                london: '0xa01cf28b0b6ce6dc3b466e995585d69486400d671fce0ea8d06beba583e6f3bb',
+                london: '0x482146829055f052063003e9cf0ffaf798a12fb58088c2667566a135b9568355',
             }[getEVMVersion()];
 
             expect(contractBytecodeHash).to.be.equal(expected);
diff --git a/test/InterchainTokenFactory.js b/test/InterchainTokenFactory.js
index fa9e687e..0e2cd5f3 100644
--- a/test/InterchainTokenFactory.js
+++ b/test/InterchainTokenFactory.js
@@ -235,18 +235,13 @@ describe('InterchainTokenFactory', () => {
         it('Should register a token if the mint amount is zero and minter is the zero address', async () => {
             const salt = keccak256('0x123456');
             tokenId = await tokenFactory.interchainTokenId(wallet.address, salt);
-            const tokenAddress = await service.interchainTokenAddress(tokenId);
-            const minterBytes = new Uint8Array();
-            const params = defaultAbiCoder.encode(['bytes', 'address'], [minterBytes, tokenAddress]);
-            const tokenManager = await getContractAt('TokenManager', await service.tokenManagerAddress(tokenId), wallet);
-
-            await expect(tokenFactory.deployInterchainToken(salt, name, symbol, decimals, 0, AddressZero))
-                .to.emit(service, 'InterchainTokenDeployed')
-                .withArgs(tokenId, tokenAddress, AddressZero, name, symbol, decimals)
-                .and.to.emit(service, 'TokenManagerDeployed')
-                .withArgs(tokenId, tokenManager.address, NATIVE_INTERCHAIN_TOKEN, params);
 
-            await checkRoles(tokenManager, AddressZero);
+            await expectRevert(
+                (gasOptions) => tokenFactory.deployInterchainToken(salt, name, symbol, decimals, 0, AddressZero, { gasOptions }),
+                tokenFactory,
+                'EmptyInterchainToken',
+                [],
+            );
         });
 
         it('Should register a token if the mint amount is greater than zero and the minter is the zero address', async () => {
diff --git a/test/InterchainTokenService.js b/test/InterchainTokenService.js
index 2cb75946..2dc561c3 100644
--- a/test/InterchainTokenService.js
+++ b/test/InterchainTokenService.js
@@ -909,13 +909,13 @@ describe('Interchain Token Service', () => {
             );
         });
 
-        it('Should revert on deploying a token manager if token handler post deploy fails', async () => {
+        it('Should revert on deploying a token manager with an empty token', async () => {
             const params = defaultAbiCoder.encode(['bytes', 'address'], [wallet.address, AddressZero]);
 
             await expectRevert(
                 (gasOptions) => service.deployTokenManager(salt, '', LOCK_UNLOCK, params, 0, gasOptions),
                 service,
-                'PostDeployFailed',
+                'TokenManagerDeploymentFailed',
             );
         });
 
diff --git a/test/TokenManager.js b/test/TokenManager.js
index 18fd33de..5d9a4a8a 100644
--- a/test/TokenManager.js
+++ b/test/TokenManager.js
@@ -92,7 +92,7 @@ describe('Token Manager', () => {
             const proxyBytecodeHash = keccak256(proxyBytecode);
 
             const expected = {
-                london: '0x8080880884e00735cc1a34bdf5c1ea6c023db60a01cfa1e951ca41ecf5fd8836',
+                london: '0x3b336208cc75ca67bdd39bdeed72871ce795e6e9cd28e20f811599ea51973ebf',
             }[getEVMVersion()];
 
             expect(proxyBytecodeHash).to.be.equal(expected);

From 046e36292f8e31024d509b39e6ce3b1027a3610d Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Fri, 20 Dec 2024 18:05:08 +0200
Subject: [PATCH 03/16] Update contracts/InterchainTokenService.sol

Co-authored-by: Milap Sheth <milap@interoplabs.io>
---
 contracts/InterchainTokenService.sol | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/contracts/InterchainTokenService.sol b/contracts/InterchainTokenService.sol
index fff6d471..84053af1 100644
--- a/contracts/InterchainTokenService.sol
+++ b/contracts/InterchainTokenService.sol
@@ -396,7 +396,7 @@ contract InterchainTokenService is
     }
 
     /**
-     * @notice Executes operations based on the payload and selector.
+     * @notice Executes the cross-chain ITS message.
      * @param commandId The unique message id.
      * @param sourceChain The chain where the transaction originates from.
      * @param sourceAddress The address of the remote ITS where the transaction originates from.

From d0fa4623466395200853762f0c4d1e8b54e282b6 Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Fri, 20 Dec 2024 18:09:03 +0200
Subject: [PATCH 04/16] Change an error a bit

---
 contracts/InterchainTokenFactory.sol             | 3 ++-
 contracts/interfaces/IInterchainTokenFactory.sol | 2 +-
 test/InterchainTokenFactory.js                   | 2 +-
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/contracts/InterchainTokenFactory.sol b/contracts/InterchainTokenFactory.sol
index 31b4422b..d21d9a84 100644
--- a/contracts/InterchainTokenFactory.sol
+++ b/contracts/InterchainTokenFactory.sol
@@ -119,6 +119,7 @@ contract InterchainTokenFactory is IInterchainTokenFactory, ITokenManagerType, M
      * @notice Deploys a new interchain token with specified parameters.
      * @dev Creates a new token and optionally mints an initial amount to a specified minter.
      * This function is `payable` because non-payable functions cannot be called in a multicall that calls other `payable` functions.
+     * Cannot deploy tokens with empty supply and no minter.
      * @param salt The unique salt for deploying the token.
      * @param name The name of the token.
      * @param symbol The symbol of the token.
@@ -150,7 +151,7 @@ contract InterchainTokenFactory is IInterchainTokenFactory, ITokenManagerType, M
 
             minterBytes = minter.toBytes();
         } else {
-            revert EmptyInterchainToken();
+            revert ZeroSupplyToken();
         }
 
         tokenId = _deployInterchainToken(deploySalt, currentChain, name, symbol, decimals, minterBytes, gasValue);
diff --git a/contracts/interfaces/IInterchainTokenFactory.sol b/contracts/interfaces/IInterchainTokenFactory.sol
index 0db2aa76..87aa83ad 100644
--- a/contracts/interfaces/IInterchainTokenFactory.sol
+++ b/contracts/interfaces/IInterchainTokenFactory.sol
@@ -19,7 +19,7 @@ interface IInterchainTokenFactory is IUpgradable, IMulticall {
     error NotSupported();
     error RemoteDeploymentNotApproved();
     error InvalidTokenId(bytes32 tokenId, bytes32 expectedTokenId);
-    error EmptyInterchainToken();
+    error ZeroSupplyToken();
 
     /// @notice Emitted when a minter approves a deployer for a remote interchain token deployment that uses a custom destinationMinter address.
     event DeployRemoteInterchainTokenApproval(
diff --git a/test/InterchainTokenFactory.js b/test/InterchainTokenFactory.js
index 0e2cd5f3..af0728c3 100644
--- a/test/InterchainTokenFactory.js
+++ b/test/InterchainTokenFactory.js
@@ -239,7 +239,7 @@ describe('InterchainTokenFactory', () => {
             await expectRevert(
                 (gasOptions) => tokenFactory.deployInterchainToken(salt, name, symbol, decimals, 0, AddressZero, { gasOptions }),
                 tokenFactory,
-                'EmptyInterchainToken',
+                'ZeroSupplyToken',
                 [],
             );
         });

From 16088d8bf1a4ffbd2dec0bdcb452994293f7312d Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Fri, 20 Dec 2024 18:12:49 +0200
Subject: [PATCH 05/16] address some comments

---
 contracts/interchain-token/InterchainToken.sol | 7 ++++++-
 package-lock.json                              | 4 ++--
 test/InterchainToken.js                        | 2 +-
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/contracts/interchain-token/InterchainToken.sol b/contracts/interchain-token/InterchainToken.sol
index 03265886..1dea362a 100644
--- a/contracts/interchain-token/InterchainToken.sol
+++ b/contracts/interchain-token/InterchainToken.sol
@@ -2,9 +2,12 @@
 
 pragma solidity ^0.8.0;
 
+import { AddressBytes } from '@axelar-network/axelar-gmp-sdk-solidity/contracts/libs/AddressBytes.sol';
+
 import { IInterchainToken } from '../interfaces/IInterchainToken.sol';
 
 import { InterchainTokenStandard } from './InterchainTokenStandard.sol';
+import { ERC20 } from './ERC20.sol';
 import { ERC20Permit } from './ERC20Permit.sol';
 import { Minter } from '../utils/Minter.sol';
 
@@ -13,7 +16,9 @@ import { Minter } from '../utils/Minter.sol';
  * @notice This contract implements an interchain token which extends InterchainToken functionality.
  * @dev This contract also inherits Minter and Implementation logic.
  */
-contract InterchainToken is InterchainTokenStandard, ERC20Permit, Minter, IInterchainToken {
+contract InterchainToken is InterchainTokenStandard, ERC20, ERC20Permit, Minter, IInterchainToken {
+    using AddressBytes for bytes;
+
     string public name;
     string public symbol;
     uint8 public decimals;
diff --git a/package-lock.json b/package-lock.json
index d2daf0e2..3b9f970a 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "@axelar-network/interchain-token-service",
-  "version": "1.2.4",
+  "version": "2.0.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@axelar-network/interchain-token-service",
-      "version": "1.2.4",
+      "version": "2.0.1",
       "license": "MIT",
       "dependencies": {
         "@axelar-network/axelar-cgp-solidity": "6.4.0",
diff --git a/test/InterchainToken.js b/test/InterchainToken.js
index 300678c7..a7ff687a 100644
--- a/test/InterchainToken.js
+++ b/test/InterchainToken.js
@@ -147,7 +147,7 @@ describe('InterchainToken', () => {
             const contractBytecodeHash = keccak256(contractBytecode);
 
             const expected = {
-                london: '0x482146829055f052063003e9cf0ffaf798a12fb58088c2667566a135b9568355',
+                london: '0xa01cf28b0b6ce6dc3b466e995585d69486400d671fce0ea8d06beba583e6f3bb',
             }[getEVMVersion()];
 
             expect(contractBytecodeHash).to.be.equal(expected);

From 82babdcaacca2314e1539c71e8ab2ba0decd64b1 Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Fri, 20 Dec 2024 18:14:33 +0200
Subject: [PATCH 06/16] revert changes to preserve bytecode

---
 contracts/interchain-token/ERC20Permit.sol | 10 ----------
 1 file changed, 10 deletions(-)

diff --git a/contracts/interchain-token/ERC20Permit.sol b/contracts/interchain-token/ERC20Permit.sol
index 00826284..b692d723 100644
--- a/contracts/interchain-token/ERC20Permit.sol
+++ b/contracts/interchain-token/ERC20Permit.sol
@@ -23,7 +23,6 @@ abstract contract ERC20Permit is IERC20, IERC20Permit, ERC20 {
      */
     bytes32 public nameHash;
 
-    // Prefix for the EIP712 structured data.
     string private constant EIP191_PREFIX_FOR_EIP712_STRUCTURED_DATA = '\x19\x01';
 
     // keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)')
@@ -72,15 +71,6 @@ abstract contract ERC20Permit is IERC20, IERC20Permit, ERC20 {
     function permit(address issuer, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) external {
         if (block.timestamp > deadline) revert PermitExpired();
 
-        // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
-        // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
-        // the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
-        // signatures from current libraries generate a unique signature with an s-value in the lower half order.
-        //
-        // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
-        // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
-        // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
-        // these malleable signatures as well.
         if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) revert InvalidS();
 
         if (v != 27 && v != 28) revert InvalidV();

From 3435efa4e8ef08d29474a32e3add80a8215cfd2d Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Fri, 20 Dec 2024 18:18:18 +0200
Subject: [PATCH 07/16] try to preserve tokenManager bytecode

---
 contracts/interfaces/ITokenManager.sol   | 1 -
 contracts/token-manager/TokenManager.sol | 8 +++-----
 test/TokenManager.js                     | 2 +-
 3 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/contracts/interfaces/ITokenManager.sol b/contracts/interfaces/ITokenManager.sol
index 23c778b2..499ab09a 100644
--- a/contracts/interfaces/ITokenManager.sol
+++ b/contracts/interfaces/ITokenManager.sol
@@ -15,7 +15,6 @@ import { IFlowLimit } from './IFlowLimit.sol';
 interface ITokenManager is IBaseTokenManager, IOperator, IFlowLimit, IImplementation {
     error TokenLinkerZeroAddress();
     error NotService(address caller);
-    error ZeroTokenAddress();
     error NotSupported();
 
     /**
diff --git a/contracts/token-manager/TokenManager.sol b/contracts/token-manager/TokenManager.sol
index dbcc61db..2c553a0c 100644
--- a/contracts/token-manager/TokenManager.sol
+++ b/contracts/token-manager/TokenManager.sol
@@ -57,9 +57,9 @@ contract TokenManager is ITokenManager, Operator, FlowLimit, Implementation, Mul
     }
 
     /**
-     * @notice Reads the token address from the proxy.
-     * @dev This function is not supported when directly called on the implementation.
-     * It must be called by the proxy. It is included here so that the interace shows this function as existing, for better UX.
+     * @notice Reads the token address from the proxy.     
+     * @dev This function is not supported when directly called on the implementation. It
+     * must be called by the proxy.
      * @return tokenAddress_ The address of the token.
      */
     function tokenAddress() external view virtual returns (address) {
@@ -69,7 +69,6 @@ contract TokenManager is ITokenManager, Operator, FlowLimit, Implementation, Mul
     /**
      * @notice A function that returns the token id.
      * @dev This will only work when implementation is called by a proxy, which stores the tokenId as an immutable.
-     * It is included here so that the interace shows this function as existing, for better UX.
      * @return bytes32 The interchain token ID.
      */
     function interchainTokenId() public pure returns (bytes32) {
@@ -91,7 +90,6 @@ contract TokenManager is ITokenManager, Operator, FlowLimit, Implementation, Mul
      */
     function getTokenAddressFromParams(bytes calldata params_) external pure returns (address tokenAddress_) {
         (, tokenAddress_) = abi.decode(params_, (bytes, address));
-        if (tokenAddress_ == address(0)) revert ZeroTokenAddress();
     }
 
     /**
diff --git a/test/TokenManager.js b/test/TokenManager.js
index 5d9a4a8a..18fd33de 100644
--- a/test/TokenManager.js
+++ b/test/TokenManager.js
@@ -92,7 +92,7 @@ describe('Token Manager', () => {
             const proxyBytecodeHash = keccak256(proxyBytecode);
 
             const expected = {
-                london: '0x3b336208cc75ca67bdd39bdeed72871ce795e6e9cd28e20f811599ea51973ebf',
+                london: '0x8080880884e00735cc1a34bdf5c1ea6c023db60a01cfa1e951ca41ecf5fd8836',
             }[getEVMVersion()];
 
             expect(proxyBytecodeHash).to.be.equal(expected);

From bcef24d820d45bbb74068d5c11986ba596108f14 Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Fri, 20 Dec 2024 18:20:19 +0200
Subject: [PATCH 08/16] trying to preserve bytecode some more

---
 contracts/interfaces/ITokenManager.sol   | 8 +++++++-
 contracts/token-manager/TokenManager.sol | 3 +--
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/contracts/interfaces/ITokenManager.sol b/contracts/interfaces/ITokenManager.sol
index 499ab09a..53dc478c 100644
--- a/contracts/interfaces/ITokenManager.sol
+++ b/contracts/interfaces/ITokenManager.sol
@@ -14,7 +14,13 @@ import { IFlowLimit } from './IFlowLimit.sol';
  */
 interface ITokenManager is IBaseTokenManager, IOperator, IFlowLimit, IImplementation {
     error TokenLinkerZeroAddress();
-    error NotService(address caller);
+    error NotService(address caller);    
+    error TakeTokenFailed();
+    error GiveTokenFailed();
+    error NotToken(address caller);
+    error ZeroAddress();
+    error AlreadyFlowLimiter(address flowLimiter);
+    error NotFlowLimiter(address flowLimiter);
     error NotSupported();
 
     /**
diff --git a/contracts/token-manager/TokenManager.sol b/contracts/token-manager/TokenManager.sol
index 2c553a0c..e6d30174 100644
--- a/contracts/token-manager/TokenManager.sol
+++ b/contracts/token-manager/TokenManager.sol
@@ -18,7 +18,6 @@ import { FlowLimit } from '../utils/FlowLimit.sol';
 /**
  * @title TokenManager
  * @notice This contract is responsible for managing tokens, such as setting locking token balances, or setting flow limits, for interchain transfers.
- * @dev Should only be used as an implementation for TokenManagerProxy.
  */
 contract TokenManager is ITokenManager, Operator, FlowLimit, Implementation, Multicall {
     using AddressBytes for bytes;
@@ -57,7 +56,7 @@ contract TokenManager is ITokenManager, Operator, FlowLimit, Implementation, Mul
     }
 
     /**
-     * @notice Reads the token address from the proxy.     
+     * @notice Reads the token address from the proxy.
      * @dev This function is not supported when directly called on the implementation. It
      * must be called by the proxy.
      * @return tokenAddress_ The address of the token.

From 426804b9ab51b3cd541dc347e217c8770666b117 Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Fri, 20 Dec 2024 18:21:25 +0200
Subject: [PATCH 09/16] some more trying to preserve bytecode

---
 contracts/interfaces/ITokenManager.sol | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/contracts/interfaces/ITokenManager.sol b/contracts/interfaces/ITokenManager.sol
index 53dc478c..50c582a9 100644
--- a/contracts/interfaces/ITokenManager.sol
+++ b/contracts/interfaces/ITokenManager.sol
@@ -14,7 +14,7 @@ import { IFlowLimit } from './IFlowLimit.sol';
  */
 interface ITokenManager is IBaseTokenManager, IOperator, IFlowLimit, IImplementation {
     error TokenLinkerZeroAddress();
-    error NotService(address caller);    
+    error NotService(address caller);
     error TakeTokenFailed();
     error GiveTokenFailed();
     error NotToken(address caller);
@@ -25,7 +25,6 @@ interface ITokenManager is IBaseTokenManager, IOperator, IFlowLimit, IImplementa
 
     /**
      * @notice Returns implementation type of this token manager.
-     * @dev This is stored in the proxy and should not be called in the implementation, but it is included here so that the interface properly tells us what functions exist.
      * @return uint256 The implementation type of this token manager.
      */
     function implementationType() external view returns (uint256);

From ab264ac1d989bff97490213e42b4b96763fb67ef Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Fri, 20 Dec 2024 18:23:14 +0200
Subject: [PATCH 10/16] finaly fixed the tokenManager bytecode

---
 contracts/interfaces/IBaseTokenManager.sol | 2 --
 1 file changed, 2 deletions(-)

diff --git a/contracts/interfaces/IBaseTokenManager.sol b/contracts/interfaces/IBaseTokenManager.sol
index b3dba446..2ceff77d 100644
--- a/contracts/interfaces/IBaseTokenManager.sol
+++ b/contracts/interfaces/IBaseTokenManager.sol
@@ -9,14 +9,12 @@ pragma solidity ^0.8.0;
 interface IBaseTokenManager {
     /**
      * @notice A function that returns the token id.
-     * @dev This is stored in the proxy and should not be called in the implementation, but it is included here so that the interface properly tells us what functions exist.
      */
     function interchainTokenId() external view returns (bytes32);
 
     /**
      * @notice A function that should return the address of the token.
      * Must be overridden in the inheriting contract.
-     * @dev This is stored in the proxy and should not be called in the implementation, but it is included here so that the interface properly tells us what functions exist.
      * @return address address of the token.
      */
     function tokenAddress() external view returns (address);

From 862eeb407266703ff1555ed8bd3601ce0106c9f3 Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Fri, 20 Dec 2024 18:28:24 +0200
Subject: [PATCH 11/16] fixed a test and a test name

---
 test/InterchainTokenFactory.js | 2 +-
 test/InterchainTokenService.js | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/InterchainTokenFactory.js b/test/InterchainTokenFactory.js
index af0728c3..be4f62a0 100644
--- a/test/InterchainTokenFactory.js
+++ b/test/InterchainTokenFactory.js
@@ -232,7 +232,7 @@ describe('InterchainTokenFactory', () => {
             await checkRoles(tokenManager, minter);
         });
 
-        it('Should register a token if the mint amount is zero and minter is the zero address', async () => {
+        it('Should revert when trying to register a token if the mint amount is zero and minter is the zero address', async () => {
             const salt = keccak256('0x123456');
             tokenId = await tokenFactory.interchainTokenId(wallet.address, salt);
 
diff --git a/test/InterchainTokenService.js b/test/InterchainTokenService.js
index 2dc561c3..2cb75946 100644
--- a/test/InterchainTokenService.js
+++ b/test/InterchainTokenService.js
@@ -909,13 +909,13 @@ describe('Interchain Token Service', () => {
             );
         });
 
-        it('Should revert on deploying a token manager with an empty token', async () => {
+        it('Should revert on deploying a token manager if token handler post deploy fails', async () => {
             const params = defaultAbiCoder.encode(['bytes', 'address'], [wallet.address, AddressZero]);
 
             await expectRevert(
                 (gasOptions) => service.deployTokenManager(salt, '', LOCK_UNLOCK, params, 0, gasOptions),
                 service,
-                'TokenManagerDeploymentFailed',
+                'PostDeployFailed',
             );
         });
 

From 5bfbc662606776a8f7b68c896d85dffd3d2b1dca Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Mon, 23 Dec 2024 13:18:01 +0200
Subject: [PATCH 12/16] Added a check for the token to exist

---
 contracts/InterchainTokenFactory.sol             | 14 ++++++++++++++
 contracts/interfaces/IInterchainTokenFactory.sol |  1 +
 test/InterchainTokenFactory.js                   |  4 ++++
 3 files changed, 19 insertions(+)

diff --git a/contracts/InterchainTokenFactory.sol b/contracts/InterchainTokenFactory.sol
index d21d9a84..93aae451 100644
--- a/contracts/InterchainTokenFactory.sol
+++ b/contracts/InterchainTokenFactory.sol
@@ -404,10 +404,24 @@ contract InterchainTokenFactory is IInterchainTokenFactory, ITokenManagerType, M
         bytes32 deploySalt = canonicalInterchainTokenDeploySalt(tokenAddress);
         string memory currentChain = '';
         uint256 gasValue = 0;
+        _checkToken(tokenAddress);
 
         tokenId = interchainTokenService.deployTokenManager(deploySalt, currentChain, TokenManagerType.LOCK_UNLOCK, params, gasValue);
     }
 
+    function _checkToken(address tokenAddress) internal view {
+        IERC20Named token = IERC20Named(tokenAddress);
+        try token.name() {} catch {
+            revert NotToken(tokenAddress);
+        }
+        try token.symbol() {} catch {
+            revert NotToken(tokenAddress);
+        }
+        try token.decimals() {} catch {
+            revert NotToken(tokenAddress);
+        }
+    }
+
     /**
      * @notice Deploys a canonical interchain token on a remote chain.
      * @param originalTokenAddress The address of the original token on the original chain.
diff --git a/contracts/interfaces/IInterchainTokenFactory.sol b/contracts/interfaces/IInterchainTokenFactory.sol
index 87aa83ad..fd63f3c7 100644
--- a/contracts/interfaces/IInterchainTokenFactory.sol
+++ b/contracts/interfaces/IInterchainTokenFactory.sol
@@ -20,6 +20,7 @@ interface IInterchainTokenFactory is IUpgradable, IMulticall {
     error RemoteDeploymentNotApproved();
     error InvalidTokenId(bytes32 tokenId, bytes32 expectedTokenId);
     error ZeroSupplyToken();
+    error NotToken(address tokenAddress);
 
     /// @notice Emitted when a minter approves a deployer for a remote interchain token deployment that uses a custom destinationMinter address.
     event DeployRemoteInterchainTokenApproval(
diff --git a/test/InterchainTokenFactory.js b/test/InterchainTokenFactory.js
index be4f62a0..b5c6d33c 100644
--- a/test/InterchainTokenFactory.js
+++ b/test/InterchainTokenFactory.js
@@ -115,6 +115,10 @@ describe('InterchainTokenFactory', () => {
                 .withArgs(tokenId, tokenManagerAddress, LOCK_UNLOCK, params);
         });
 
+        it('Should not register a non-existing token', async () => {
+            await expectRevert((gasOptions) => tokenFactory.registerCanonicalInterchainToken(tokenFactory.address, { gasOptions }), tokenFactory, "NotToken", [tokenFactory.address])
+        });
+
         it('Should initiate a remote interchain token deployment with no original chain name provided', async () => {
             const gasValue = 1234;
             const payload = defaultAbiCoder.encode(

From 55b731357261aa17fe35e1bf4837fab548836fd4 Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Mon, 23 Dec 2024 16:10:51 +0200
Subject: [PATCH 13/16] made lint and slither happy

---
 contracts/InterchainTokenFactory.sol | 6 ++++++
 contracts/TokenHandler.sol           | 2 +-
 test/InterchainTokenFactory.js       | 7 ++++++-
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/contracts/InterchainTokenFactory.sol b/contracts/InterchainTokenFactory.sol
index 93aae451..31031ecb 100644
--- a/contracts/InterchainTokenFactory.sol
+++ b/contracts/InterchainTokenFactory.sol
@@ -411,12 +411,18 @@ contract InterchainTokenFactory is IInterchainTokenFactory, ITokenManagerType, M
 
     function _checkToken(address tokenAddress) internal view {
         IERC20Named token = IERC20Named(tokenAddress);
+        
+        // slither-disable-next-line unused-return
         try token.name() {} catch {
             revert NotToken(tokenAddress);
         }
+
+        // slither-disable-next-line unused-return
         try token.symbol() {} catch {
             revert NotToken(tokenAddress);
         }
+
+        // slither-disable-next-line unused-return
         try token.decimals() {} catch {
             revert NotToken(tokenAddress);
         }
diff --git a/contracts/TokenHandler.sol b/contracts/TokenHandler.sol
index 69932021..8db4492d 100644
--- a/contracts/TokenHandler.sol
+++ b/contracts/TokenHandler.sol
@@ -4,7 +4,7 @@ pragma solidity ^0.8.0;
 
 import { ITokenHandler } from './interfaces/ITokenHandler.sol';
 import { IERC20 } from '@axelar-network/axelar-gmp-sdk-solidity/contracts/interfaces/IERC20.sol';
-import { SafeTokenTransfer, SafeTokenTransferFrom, SafeTokenCall } from '@axelar-network/axelar-gmp-sdk-solidity/contracts/libs/SafeTransfer.sol';
+import { SafeTokenTransferFrom, SafeTokenCall } from '@axelar-network/axelar-gmp-sdk-solidity/contracts/libs/SafeTransfer.sol';
 import { ReentrancyGuard } from '@axelar-network/axelar-gmp-sdk-solidity/contracts/utils/ReentrancyGuard.sol';
 import { Create3AddressFixed } from './utils/Create3AddressFixed.sol';
 
diff --git a/test/InterchainTokenFactory.js b/test/InterchainTokenFactory.js
index b5c6d33c..1bc83ca2 100644
--- a/test/InterchainTokenFactory.js
+++ b/test/InterchainTokenFactory.js
@@ -116,7 +116,12 @@ describe('InterchainTokenFactory', () => {
         });
 
         it('Should not register a non-existing token', async () => {
-            await expectRevert((gasOptions) => tokenFactory.registerCanonicalInterchainToken(tokenFactory.address, { gasOptions }), tokenFactory, "NotToken", [tokenFactory.address])
+            await expectRevert(
+                (gasOptions) => tokenFactory.registerCanonicalInterchainToken(tokenFactory.address, { gasOptions }),
+                tokenFactory,
+                'NotToken',
+                [tokenFactory.address],
+            );
         });
 
         it('Should initiate a remote interchain token deployment with no original chain name provided', async () => {

From a56fd79f0e507c0803d59062ac5b7f83954f0722 Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Mon, 23 Dec 2024 17:12:52 +0200
Subject: [PATCH 14/16] prettier

---
 contracts/InterchainTokenFactory.sol | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/contracts/InterchainTokenFactory.sol b/contracts/InterchainTokenFactory.sol
index 31031ecb..c1b016b7 100644
--- a/contracts/InterchainTokenFactory.sol
+++ b/contracts/InterchainTokenFactory.sol
@@ -411,7 +411,7 @@ contract InterchainTokenFactory is IInterchainTokenFactory, ITokenManagerType, M
 
     function _checkToken(address tokenAddress) internal view {
         IERC20Named token = IERC20Named(tokenAddress);
-        
+
         // slither-disable-next-line unused-return
         try token.name() {} catch {
             revert NotToken(tokenAddress);

From 24e5797c46a4dcd44bb4136581d9af9507a4c69b Mon Sep 17 00:00:00 2001
From: Foivos <foivos@umich.edu>
Date: Thu, 2 Jan 2025 13:38:07 +0200
Subject: [PATCH 15/16] using a function to get token metadata now

---
 contracts/InterchainTokenFactory.sol | 28 ++++++++++++++++++----------
 1 file changed, 18 insertions(+), 10 deletions(-)

diff --git a/contracts/InterchainTokenFactory.sol b/contracts/InterchainTokenFactory.sol
index c1b016b7..a532eb47 100644
--- a/contracts/InterchainTokenFactory.sol
+++ b/contracts/InterchainTokenFactory.sol
@@ -385,11 +385,15 @@ contract InterchainTokenFactory is IInterchainTokenFactory, ITokenManagerType, M
         uint256 gasValue
     ) internal returns (bytes32 tokenId) {
         bytes32 expectedTokenId = _interchainTokenId(deploySalt);
+
         // Ensure that a local token has been registered for the tokenId
-        IERC20Named token = IERC20Named(interchainTokenService.registeredTokenAddress(expectedTokenId));
+        string memory name;
+        string memory symbol;
+        uint8 decimals;
+        (name, symbol, decimals) = _getTokenMetadata(interchainTokenService.registeredTokenAddress(expectedTokenId));
 
         // The local token must expose the name, symbol, and decimals metadata
-        tokenId = _deployInterchainToken(deploySalt, destinationChain, token.name(), token.symbol(), token.decimals(), minter, gasValue);
+        tokenId = _deployInterchainToken(deploySalt, destinationChain, name, symbol, decimals, minter, gasValue);
         if (tokenId != expectedTokenId) revert InvalidTokenId(tokenId, expectedTokenId);
     }
 
@@ -404,26 +408,30 @@ contract InterchainTokenFactory is IInterchainTokenFactory, ITokenManagerType, M
         bytes32 deploySalt = canonicalInterchainTokenDeploySalt(tokenAddress);
         string memory currentChain = '';
         uint256 gasValue = 0;
-        _checkToken(tokenAddress);
+        // slither-disable-next-line unused-return
+        _getTokenMetadata(tokenAddress);
 
         tokenId = interchainTokenService.deployTokenManager(deploySalt, currentChain, TokenManagerType.LOCK_UNLOCK, params, gasValue);
     }
 
-    function _checkToken(address tokenAddress) internal view {
+    function _getTokenMetadata(address tokenAddress) internal view returns (string memory name, string memory symbol, uint8 decimals) {
         IERC20Named token = IERC20Named(tokenAddress);
 
-        // slither-disable-next-line unused-return
-        try token.name() {} catch {
+        try token.name() returns (string memory name_) {
+            name = name_;
+        } catch {
             revert NotToken(tokenAddress);
         }
 
-        // slither-disable-next-line unused-return
-        try token.symbol() {} catch {
+        try token.symbol() returns (string memory symbol_) {
+            symbol = symbol_;
+        } catch {
             revert NotToken(tokenAddress);
         }
 
-        // slither-disable-next-line unused-return
-        try token.decimals() {} catch {
+        try token.decimals() returns (uint8 decimals_) {
+            decimals = decimals_;
+        } catch {
             revert NotToken(tokenAddress);
         }
     }

From eb4c928e1b7d360925cef8dde6702105897b0b1d Mon Sep 17 00:00:00 2001
From: Milap Sheth <milap@interoplabs.io>
Date: Mon, 6 Jan 2025 10:41:39 -0500
Subject: [PATCH 16/16] cleanup comments

---
 contracts/InterchainTokenFactory.sol | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/contracts/InterchainTokenFactory.sol b/contracts/InterchainTokenFactory.sol
index a532eb47..51c0e439 100644
--- a/contracts/InterchainTokenFactory.sol
+++ b/contracts/InterchainTokenFactory.sol
@@ -384,15 +384,13 @@ contract InterchainTokenFactory is IInterchainTokenFactory, ITokenManagerType, M
         bytes memory minter,
         uint256 gasValue
     ) internal returns (bytes32 tokenId) {
+        // Ensure that a token is registered locally for the tokenId before allowing a remote deployment
         bytes32 expectedTokenId = _interchainTokenId(deploySalt);
-
-        // Ensure that a local token has been registered for the tokenId
-        string memory name;
-        string memory symbol;
-        uint8 decimals;
-        (name, symbol, decimals) = _getTokenMetadata(interchainTokenService.registeredTokenAddress(expectedTokenId));
+        address tokenAddress = interchainTokenService.registeredTokenAddress(expectedTokenId);
 
         // The local token must expose the name, symbol, and decimals metadata
+        (string memory name, string memory symbol, uint8 decimals) = _getTokenMetadata(tokenAddress);
+
         tokenId = _deployInterchainToken(deploySalt, destinationChain, name, symbol, decimals, minter, gasValue);
         if (tokenId != expectedTokenId) revert InvalidTokenId(tokenId, expectedTokenId);
     }
@@ -408,12 +406,21 @@ contract InterchainTokenFactory is IInterchainTokenFactory, ITokenManagerType, M
         bytes32 deploySalt = canonicalInterchainTokenDeploySalt(tokenAddress);
         string memory currentChain = '';
         uint256 gasValue = 0;
+
+        // Ensure that the ERC20 token has metadata before registering it
         // slither-disable-next-line unused-return
         _getTokenMetadata(tokenAddress);
 
         tokenId = interchainTokenService.deployTokenManager(deploySalt, currentChain, TokenManagerType.LOCK_UNLOCK, params, gasValue);
     }
 
+    /**
+     * @notice Retrieves the metadata of an ERC20 token. Reverts with `NotToken` error if metadata is not available.
+     * @param tokenAddress The address of the token.
+     * @return name The name of the token.
+     * @return symbol The symbol of the token.
+     * @return decimals The number of decimals for the token.
+     */
     function _getTokenMetadata(address tokenAddress) internal view returns (string memory name, string memory symbol, uint8 decimals) {
         IERC20Named token = IERC20Named(tokenAddress);