feat(its): add a registerCustomToken function in ITS and add support …

…for it in factory (#322)

Co-authored-by: Milap Sheth <[email protected]>

contracts/InterchainTokenFactory.sol

@@ -403,23 +403,14 @@ contract InterchainTokenFactory is IInterchainTokenFactory, Multicall, Upgradabl
      */
     function registerCanonicalInterchainToken(address tokenAddress) external payable returns (bytes32 tokenId) {
         bytes32 deploySalt = canonicalInterchainTokenDeploySalt(tokenAddress);
-        string memory currentChain = '';
         // No custom operator is set for canonical token registration
         bytes memory linkParams = '';
-        uint256 gasValue = 0;
 
         // Ensure that the ERC20 token has metadata before registering it
         // slither-disable-next-line unused-return
         _getTokenMetadata(tokenAddress);
 
-        tokenId = interchainTokenService.linkToken(
-            deploySalt,
-            currentChain,
-            tokenAddress.toBytes(),
-            TokenManagerType.LOCK_UNLOCK,
-            linkParams,
-            gasValue
-        );
+        tokenId = interchainTokenService.registerCustomToken(deploySalt, tokenAddress, TokenManagerType.LOCK_UNLOCK, linkParams);
     }
 
     /**
@@ -530,13 +521,12 @@ contract InterchainTokenFactory is IInterchainTokenFactory, Multicall, Upgradabl
         uint256 gasValue
     ) external payable returns (bytes32 tokenId) {
         bytes32 deploySalt = linkedTokenDeploySalt(msg.sender, salt);
-        string memory currentChain = '';
         bytes memory linkParams = '';
         if (operator != address(0)) {
             linkParams = operator.toBytes();
         }
 
-        tokenId = interchainTokenService.linkToken(deploySalt, currentChain, tokenAddress.toBytes(), tokenManagerType, linkParams, 0);
+        tokenId = interchainTokenService.registerCustomToken(deploySalt, tokenAddress, tokenManagerType, linkParams);
 
         interchainTokenService.registerTokenMetadata{ value: gasValue }(tokenAddress, gasValue);
     }

contracts/InterchainTokenService.sol

@@ -175,6 +175,15 @@ contract InterchainTokenService is
         _;
     }
 
+    /**
+     * @notice This modifier is used to ensure that only a the token factory can call a function.
+     */
+    modifier onlyTokenFactory() {
+        if (msg.sender != interchainTokenFactory) revert NotInterchainTokenFactory(msg.sender);
+
+        _;
+    }
+
     /*****\
     GETTERS
     \*****/
@@ -279,6 +288,30 @@ contract InterchainTokenService is
         );
     }
 
+    /**
+     * @notice Only to be used by the InterchainTokenFactory to register custom tokens to this chain. Then link token can be used to register those tokens to other chains.
+     * @param salt A unique salt to derive tokenId from.
+     * @param tokenManagerType The type of the token manager to use for the token registration.
+     * @param linkParams The operator for the token.
+     */
+    function registerCustomToken(
+        bytes32 salt,
+        address tokenAddress,
+        TokenManagerType tokenManagerType,
+        bytes calldata linkParams
+    ) external payable whenNotPaused onlyTokenFactory returns (bytes32 tokenId) {
+        // Custom token managers can't be deployed with native interchain token type, which is reserved for interchain tokens
+        if (tokenManagerType == TokenManagerType.NATIVE_INTERCHAIN_TOKEN) revert CannotDeploy(tokenManagerType);
+
+        address deployer = TOKEN_FACTORY_DEPLOYER;
+
+        tokenId = interchainTokenId(deployer, salt);
+
+        emit InterchainTokenIdClaimed(tokenId, deployer, salt);
+
+        _deployTokenManager(tokenId, tokenManagerType, tokenAddress, linkParams);
+    }
+
     /**
      * @notice If `destinationChain` is an empty string, this function will register the token address on the current chain.
      * Otherwise, it will link the token address on the destination chain with the token corresponding to the tokenId on the current chain.
@@ -305,27 +338,38 @@ contract InterchainTokenService is
         // Custom token managers can't be deployed with native interchain token type, which is reserved for interchain tokens
         if (tokenManagerType == TokenManagerType.NATIVE_INTERCHAIN_TOKEN) revert CannotDeploy(tokenManagerType);
 
+        // Cannot deploy to this chain using linkToken anymore
+        if (bytes(destinationChain).length == 0) {
+            revert NotSupported();
+        }
+
+        // Cannot deploy to this chain using linkToken anymore
+        if (chainNameHash == keccak256(bytes(destinationChain))) revert CannotDeployRemotelyToSelf();
+
         address deployer = msg.sender;
 
         if (deployer == interchainTokenFactory) {
             deployer = TOKEN_FACTORY_DEPLOYER;
-        } else if (bytes(destinationChain).length == 0) {
-            // TODO: Only support linking new tokens via ITS factory, to include chain name in token id derivation
-            // Custom token usage needs to be moved to ITS factory tests
-            // revert NotSupported();
         }
 
         tokenId = interchainTokenId(deployer, salt);
 
         emit InterchainTokenIdClaimed(tokenId, deployer, salt);
 
-        if (bytes(destinationChain).length == 0) {
-            _deployTokenManager(tokenId, tokenManagerType, destinationTokenAddress.toAddress(), linkParams);
-        } else {
-            if (chainNameHash == keccak256(bytes(destinationChain))) revert CannotDeployRemotelyToSelf();
+        bytes memory sourceTokenAddress = registeredTokenAddress(tokenId).toBytes();
 
-            _linkToken(tokenId, destinationChain, destinationTokenAddress, tokenManagerType, linkParams, gasValue);
-        }
+        emit LinkTokenStarted(tokenId, destinationChain, sourceTokenAddress, destinationTokenAddress, tokenManagerType, linkParams);
+
+        bytes memory payload = abi.encode(
+            MESSAGE_TYPE_LINK_TOKEN,
+            tokenId,
+            tokenManagerType,
+            sourceTokenAddress,
+            destinationTokenAddress,
+            linkParams
+        );
+
+        _routeMessage(destinationChain, payload, IGatewayCaller.MetadataVersion.CONTRACT_CALL, gasValue);
     }
 
     /**
@@ -352,15 +396,8 @@ contract InterchainTokenService is
         uint8 decimals,
         bytes memory minter,
         uint256 gasValue
-    ) external payable whenNotPaused returns (bytes32 tokenId) {
-        address deployer = msg.sender;
-
-        if (deployer == interchainTokenFactory) {
-            deployer = TOKEN_FACTORY_DEPLOYER;
-        } else if (trustedAddressHash(chainName()) == ITS_HUB_ROUTING_IDENTIFIER_HASH) {
-            // Currently, deployments directly on ITS contract (instead of ITS Factory) are restricted for ITS contracts deployed on Amplifier, i.e registered with the Hub
-            revert NotSupported();
-        }
+    ) external payable whenNotPaused onlyTokenFactory returns (bytes32 tokenId) {
+        address deployer = TOKEN_FACTORY_DEPLOYER;
 
         tokenId = interchainTokenId(deployer, salt);
 
@@ -863,40 +900,6 @@ contract InterchainTokenService is
         return (messageType, originalSourceChain, payload);
     }
 
-    /**
-     * @notice Deploys a token manager on a destination chain.
-     * @param tokenId The ID of the token.
-     * @param destinationChain The chain where the token manager will be deployed.
-     * @param destinationTokenAddress The address of the token on the destination chain.
-     * @param tokenManagerType The type of token manager to be deployed.
-     * @param params Additional parameters for the token linking.
-     * @param gasValue The amount of gas to be paid for the transaction.
-     */
-    function _linkToken(
-        bytes32 tokenId,
-        string calldata destinationChain,
-        bytes calldata destinationTokenAddress,
-        TokenManagerType tokenManagerType,
-        bytes calldata params,
-        uint256 gasValue
-    ) internal {
-        // slither-disable-next-line unused-return
-        bytes memory sourceTokenAddress = registeredTokenAddress(tokenId).toBytes();
-
-        emit LinkTokenStarted(tokenId, destinationChain, sourceTokenAddress, destinationTokenAddress, tokenManagerType, params);
-
-        bytes memory payload = abi.encode(
-            MESSAGE_TYPE_LINK_TOKEN,
-            tokenId,
-            tokenManagerType,
-            sourceTokenAddress,
-            destinationTokenAddress,
-            params
-        );
-
-        _routeMessage(destinationChain, payload, IGatewayCaller.MetadataVersion.CONTRACT_CALL, gasValue);
-    }
-
     /**
      * @notice Deploys an interchain token on a destination chain.
      * @param tokenId The ID of the token.

contracts/interfaces/IInterchainTokenService.sol

@@ -55,6 +55,7 @@ interface IInterchainTokenService is
     error EmptyDestinationAddress();
     error EmptyTokenAddress();
     error NotSupported();
+    error NotInterchainTokenFactory(address sender);
 
     event InterchainTransfer(
         bytes32 indexed tokenId,
@@ -181,6 +182,19 @@ interface IInterchainTokenService is
      */
     function registerTokenMetadata(address tokenAddress, uint256 gasValue) external payable;
 
+    /**
+     * @notice Only to be used by the InterchainTokenFactory to register custom tokens to this chain. Then link token can be used to register those tokens to other chains.
+     * @param salt A unique salt to derive tokenId from.
+     * @param tokenManagerType The type of the token manager to use for the token registration.
+     * @param linkParams The operator for the token.
+     */
+    function registerCustomToken(
+        bytes32 salt,
+        address tokenAddress,
+        TokenManagerType tokenManagerType,
+        bytes calldata linkParams
+    ) external payable returns (bytes32 tokenId);
+
     /**
      * @notice If `destinationChain` is an empty string, this function will register the token address on the current chain.
      * Otherwise, it will link the token address on the destination chain with the token corresponding to the tokenId on the current chain.

scripts/deploy.js

@@ -142,5 +142,6 @@ module.exports = {
     deployMockGateway,
     deployGasService,
     deployInterchainTokenService,
+    deployInterchainTokenFactory,
     deployAll,
 };

test/AddressDerivation.js

@@ -47,22 +47,6 @@ if (isHardhat) {
         });
 
         describe('Interchain Token Service Deployments', () => {
-            it('Should derive the correct token address for interchain token deployment on source chain', async () => {
-                const salt = getSaltFromKey('deployInterchainToken');
-                const tokenId = await service.interchainTokenId(wallet.address, salt);
-
-                const expectedTokenAddress = '0x2b7c2c1f7297BB9a573Fb970D086F0d113722Ceb';
-                const expectedTokenManagerAddress = '0x1248d7831b5B231147bfbDb5e2b29B0110EeC9C8';
-
-                const params = defaultAbiCoder.encode(['bytes', 'address'], [wallet.address, expectedTokenAddress]);
-
-                await expect(service.deployInterchainToken(salt, '', tokenName, tokenSymbol, tokenDecimals, wallet.address, 0))
-                    .to.emit(service, 'InterchainTokenDeployed')
-                    .withArgs(tokenId, expectedTokenAddress, wallet.address, tokenName, tokenSymbol, tokenDecimals)
-                    .to.emit(service, 'TokenManagerDeployed')
-                    .withArgs(tokenId, expectedTokenManagerAddress, NATIVE_INTERCHAIN_TOKEN, params);
-            });
-
             it('Should derive the correct token address for remote interchain token deployment', async () => {
                 const salt = getSaltFromKey('deployRemoteInterchainToken');
                 const tokenId = await service.interchainTokenId(wallet.address, salt);