Allow arbitrary transact

contracts/src/AgentExecutor.sol

@@ -16,20 +16,15 @@ contract AgentExecutor {
     using SafeNativeTransfer for address payable;
     using Call for address;
 
-    error CallExternalFailed();
-
     /// @dev Execute a message which originated from the Polkadot side of the bridge. In other terms,
     /// the `data` parameter is constructed by the BridgeHub parachain.
     ///
-    function execute(AgentExecuteCommand command, bytes memory params) external {
+    function execute(bytes memory data) external {
+        (AgentExecuteCommand command, bytes memory params) = abi.decode(data, (AgentExecuteCommand, bytes));
         if (command == AgentExecuteCommand.TransferToken) {
             (address token, address recipient, uint128 amount) = abi.decode(params, (address, address, uint128));
             _transferToken(token, recipient, amount);
         }
-        if (command == AgentExecuteCommand.Transact) {
-            (address target, bytes memory payload, uint64 dynamicGas) = abi.decode(params, (address, bytes, uint64));
-            _executeCall(target, payload, dynamicGas);
-        }
     }
 
     /// @dev Transfer ether to `recipient`. Unlike `_transferToken` This logic is not nested within `execute`,
@@ -45,10 +40,7 @@ contract AgentExecutor {
     }
 
     /// @dev Call a contract at the given address, with provided bytes as payload.
-    function _executeCall(address target, bytes memory payload, uint64 dynamicGas) internal {
-        bool success = target.safeCall(dynamicGas, 0, payload);
-        if (!success) {
-            revert CallExternalFailed();
-        }
+    function executeCall(address target, bytes memory payload, uint64 dynamicGas) external returns (bool) {
+        return target.safeCall(dynamicGas, 0, payload);
     }
 }

contracts/src/Gateway.sol

@@ -41,7 +41,7 @@ import {
     TransferNativeFromAgentParams,
     SetTokenTransferFeesParams,
     SetPricingParametersParams,
-    SetSafeCallsParams
+    TransactCallParams
 } from "./Params.sol";
 
 import {CoreStorage} from "./storage/CoreStorage.sol";
@@ -96,7 +96,7 @@ contract Gateway is IGateway, IInitializable, IUpgradable {
     error AgentExecutionFailed(bytes returndata);
     error InvalidAgentExecutionPayload();
     error InvalidConstructorParams();
-    error NoPermission();
+    error AgentTransactCallFailed();
 
     // Message handlers can only be dispatched by the gateway itself
     modifier onlySelf() {
@@ -214,6 +214,11 @@ contract Gateway is IGateway, IInitializable, IUpgradable {
             catch {
                 success = false;
             }
+        } else if (message.command == Command.Transact) {
+            try Gateway(this).transact{gas: maxDispatchGas}(message.params) {}
+            catch {
+                success = false;
+            }
         }
 
         // Calculate a gas refund, capped to protect against huge spikes in `tx.gasprice`
@@ -277,26 +282,12 @@ contract Gateway is IGateway, IInitializable, IUpgradable {
             revert InvalidAgentExecutionPayload();
         }
 
-        (AgentExecuteCommand command, bytes memory commandParams) =
-            abi.decode(params.payload, (AgentExecuteCommand, bytes));
-        if (command == AgentExecuteCommand.Transact) {
-            (address target,,) = abi.decode(commandParams, (address, bytes, uint64));
-            // blacklist to check with
-            if (
-                target == address(this) || target == agent || target == AGENT_EXECUTOR
-                    || Assets.isTokenRegistered(target)
-            ) {
-                revert NoPermission();
-            }
-        }
-
-        bytes memory call = abi.encodeCall(AgentExecutor.execute, (command, commandParams));
+        bytes memory call = abi.encodeCall(AgentExecutor.execute, params.payload);
 
         (bool success, bytes memory returndata) = Agent(payable(agent)).invoke(AGENT_EXECUTOR, call);
         if (!success) {
             revert AgentExecutionFailed(returndata);
         }
-        emit AgentExecuted(params.agentID);
     }
 
     /// @dev Create an agent for a consensus system on Polkadot
@@ -398,6 +389,20 @@ contract Gateway is IGateway, IInitializable, IUpgradable {
         emit PricingParametersChanged();
     }
 
+    // @dev Transact
+    function transact(bytes calldata data) external onlySelf {
+        TransactCallParams memory params = abi.decode(data, (TransactCallParams));
+        address agent = _ensureAgent(params.agentID);
+        bytes memory call =
+            abi.encodeCall(AgentExecutor.executeCall, (params.target, params.payload, params.dynamicGas));
+        (, bytes memory result) = Agent(payable(agent)).invoke(AGENT_EXECUTOR, call);
+        (bool success) = abi.decode(result, (bool));
+        if (!success) {
+            revert AgentTransactCallFailed();
+        }
+        emit TransactExecuted(params.agentID, params.target, params.payload);
+    }
+
     /**
      * Assets
      */

contracts/src/Params.sol

@@ -83,10 +83,14 @@ struct SetPricingParametersParams {
     UD60x18 multiplier;
 }
 
-// Payload for SetSafeCalls
-struct SetSafeCallsParams {
+// Payload for TransactCall
+struct TransactCallParams {
+    /// @dev The agent ID of the consensus system
+    bytes32 agentID;
     /// @dev The target contract
     address target;
-    /// @dev The selector of the function
-    bytes4[] selectors;
+    /// @dev Payload of the call
+    bytes payload;
+    /// @dev Max gas cost of the call
+    uint64 dynamicGas;
 }

contracts/src/Types.sol

@@ -84,12 +84,12 @@ enum Command {
     SetOperatingMode,
     TransferNativeFromAgent,
     SetTokenTransferFees,
-    SetPricingParameters
+    SetPricingParameters,
+    Transact
 }
 
 enum AgentExecuteCommand {
-    TransferToken,
-    Transact
+    TransferToken
 }
 
 /// @dev Application-level costs for a message

contracts/src/interfaces/IGateway.sol

@@ -20,9 +20,6 @@ interface IGateway {
     // Emitted when an agent has been created for a consensus system on Polkadot
     event AgentCreated(bytes32 agentID, address agent);
 
-    // Emitted when an agent dispatch a safe call
-    event AgentExecuted(bytes32 agentID);
-
     // Emitted when a channel has been created
     event ChannelCreated(ChannelID indexed channelID);
 
@@ -35,12 +32,11 @@ interface IGateway {
     // Emitted when pricing params updated
     event PricingParametersChanged();
 
-    // Emitted when safe call filter updated
-    event SafeCallFilterChanged();
-
     // Emitted when funds are withdrawn from an agent
     event AgentFundsWithdrawn(bytes32 indexed agentID, address indexed recipient, uint256 amount);
 
+    event TransactExecuted(bytes32 indexed agentID, address indexed target, bytes payload);
+
     /**
      * Getters
      */

contracts/test/Gateway.t.sol

@@ -36,7 +36,7 @@ import {
     TransferNativeFromAgentParams,
     SetTokenTransferFeesParams,
     SetPricingParametersParams,
-    SetSafeCallsParams
+    TransactCallParams
 } from "../src/Params.sol";
 
 import {
@@ -866,67 +866,54 @@ contract GatewayTest is Test {
         );
     }
 
-    function testAgentExecutionTransact() public {
-        bytes memory payload = abi.encodeWithSignature("sayHello(string)", "Clara");
+    function testAgentExecutionTransactSuccess() public {
+        bytes memory payload = abi.encodeWithSignature("sayHello(string)", "World");
 
-        AgentExecuteParams memory params = AgentExecuteParams({
+        TransactCallParams memory params = TransactCallParams({
             agentID: assetHubAgentID,
-            payload: abi.encode(AgentExecuteCommand.Transact, abi.encode(address(helloWorld), payload, 100000))
+            target: address(helloWorld),
+            payload: payload,
+            dynamicGas: 100000
         });
 
         // Expect the HelloWorld contract to emit `SaidHello`
         vm.expectEmit(true, false, false, false);
-        emit SaidHello("Hello there, Clara");
-
-        MockGateway(address(gateway)).agentExecutePublic(abi.encode(params));
-    }
-
-    function testAgentExecutionTransactNoPermission() public {
-        bytes memory payload = abi.encodeWithSignature("invoke(address,bytes)");
-
-        AgentExecuteParams memory params = AgentExecuteParams({
-            agentID: assetHubAgentID,
-            payload: abi.encode(AgentExecuteCommand.Transact, abi.encode(address(assetHubAgent), payload, 100000))
-        });
+        emit SaidHello("Hello there, World");
 
-        vm.expectRevert(Gateway.NoPermission.selector);
-
-        MockGateway(address(gateway)).agentExecutePublic(abi.encode(params));
+        MockGateway(address(gateway)).transactPublic(abi.encode(params));
     }
 
     function testAgentExecutionTransactFail() public {
         bytes memory payload = abi.encodeWithSignature("revertUnauthorized()");
 
-        AgentExecuteParams memory params = AgentExecuteParams({
+        TransactCallParams memory params = TransactCallParams({
             agentID: assetHubAgentID,
-            payload: abi.encode(AgentExecuteCommand.Transact, abi.encode(address(helloWorld), payload, 100000))
+            target: address(helloWorld),
+            payload: payload,
+            dynamicGas: 100000
         });
 
-        vm.expectRevert(
-            abi.encodeWithSelector(
-                Gateway.AgentExecutionFailed.selector, abi.encodeWithSelector(AgentExecutor.CallExternalFailed.selector)
-            )
-        );
+        vm.expectRevert(abi.encodeWithSelector(Gateway.AgentTransactCallFailed.selector));
 
-        MockGateway(address(gateway)).agentExecutePublic(abi.encode(params));
+        MockGateway(address(gateway)).transactPublic(abi.encode(params));
     }
 
     function testAgentExecutionTransactRetBomb() public {
         bytes memory payload = abi.encodeWithSignature("retBomb()");
 
-        AgentExecuteParams memory params = AgentExecuteParams({
+        TransactCallParams memory params = TransactCallParams({
             agentID: assetHubAgentID,
-            payload: abi.encode(AgentExecuteCommand.Transact, abi.encode(address(helloWorld), payload, 30000000))
+            target: address(helloWorld),
+            payload: payload,
+            dynamicGas: 100000
         });
 
-        // Expect Gateway contract to emit `AgentExecuted`
-        vm.expectEmit(true, false, false, false);
-        emit IGateway.AgentExecuted(assetHubAgentID);
+        vm.expectRevert(abi.encodeWithSelector(Gateway.AgentTransactCallFailed.selector));
 
-        MockGateway(address(gateway)).agentExecutePublic(abi.encode(params));
+        MockGateway(address(gateway)).transactPublic(abi.encode(params));
     }
 
-    function testAgentExecutionTransactToTransferERC20() public {
+    function testAgentTransferERC20WithTransactShouldBeAllowed() public {
         testRegisterToken();
 
         token.transfer(address(assetHubAgent), 200);
@@ -936,16 +923,12 @@ contract GatewayTest is Test {
         uint256 amount = 50;
         bytes memory payload = abi.encodeCall(IERC20.transfer, (account1, amount));
 
-        AgentExecuteParams memory params = AgentExecuteParams({
-            agentID: assetHubAgentID,
-            payload: abi.encode(AgentExecuteCommand.Transact, abi.encode(address(token), payload, 100000))
-        });
+        TransactCallParams memory params =
+            TransactCallParams({agentID: assetHubAgentID, target: address(token), payload: payload, dynamicGas: 100000});
 
-        vm.expectRevert(Gateway.NoPermission.selector);
-
-        MockGateway(address(gateway)).agentExecutePublic(abi.encode(params));
+        MockGateway(address(gateway)).transactPublic(abi.encode(params));
 
         uint256 balanceAfter = IERC20(address(token)).balanceOf(account1);
-        assertEq(balanceBefore, balanceAfter);
+        assertEq(balanceBefore + amount, balanceAfter);
     }
 }

contracts/test/mocks/HelloWorld.sol

@@ -11,10 +11,6 @@ contract HelloWorld {
         emit SaidHello(fullMessage);
     }
 
-    function sayHello2(string memory _text) public {
-        this.sayHello(_text);
-    }
-
     function revertUnauthorized() public pure {
         revert Unauthorized();
     }

contracts/test/mocks/MockGateway.sol

@@ -76,4 +76,8 @@ contract MockGateway is Gateway {
     function setPricingParametersPublic(bytes calldata params) external {
         this.setPricingParameters(params);
     }
+
+    function transactPublic(bytes calldata params) external {
+        this.transact(params);
+    }
 }