Merge pull request #37 from forta-network/caner/firewall-router

Add FirewallRouter to support ExternalFirewall upgradeability

src/FirewallRouter.sol

@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GNU General Public License Version 3
+// See license at: https://github.com/forta-network/forta-firewall-contracts/blob/master/LICENSE-GPLv3.md
+
+pragma solidity ^0.8.25;
+
+import "./interfaces/IExternalFirewall.sol";
+import "./interfaces/ICheckpointHook.sol";
+import "./interfaces/IFirewallAccess.sol";
+import "./FirewallPermissions.sol";
+
+/**
+ * @notice This contract provides external firewall upgradeability.
+ */
+contract FirewallRouter is IExternalFirewall, FirewallPermissions {
+    IExternalFirewall public firewall;
+
+    constructor(IExternalFirewall _firewall, IFirewallAccess _firewallAccess) {
+        firewall = _firewall;
+        _updateFirewallAccess(_firewallAccess);
+    }
+
+    /**
+     * @notice Allows executing checkpoints externally from an integrator contract. The selector
+     * is checked against the checkpoints configured on this contract.
+     * @param selector Selector of the function which the checkpoint is configured and executed for
+     * @param ref The reference number to compare with the threshold
+     */
+    function executeCheckpoint(address caller, bytes4 selector, uint256 ref) public onlyCheckpointExecutor {
+        firewall.executeCheckpoint(caller, selector, ref);
+    }
+
+    /**
+     * @notice Allows executing checkpoints externally from an integrator contract. The selector
+     * is checked against the checkpoints configured on this contract.
+     * @param selector Selector of the function which the checkpoint is configured and executed for
+     * @param input The input value to use in checkpoint hash computation
+     */
+    function executeCheckpoint(address caller, bytes4 selector, bytes32 input) public onlyCheckpointExecutor {
+        firewall.executeCheckpoint(caller, selector, input);
+    }
+
+    /**
+     * @notice Accepts and stores an attestation to the transient storage introduced
+     * with EIP-1153. Multiple contracts that operate in the same transaction can call
+     * a singleton of this contract. The stored values are later used during checkpoint
+     * execution.
+     * @param attestation The set of fields that correspond to and enable the execution of call(s)
+     * @param attestationSignature Signature of EIP-712 message
+     */
+    function saveAttestation(Attestation calldata attestation, bytes calldata attestationSignature) public {
+        firewall.saveAttestation(attestation, attestationSignature);
+    }
+
+    function updateFirewall(IExternalFirewall newFirewall) public onlyFirewallAdmin {
+        firewall = newFirewall;
+    }
+}

src/examples/ExternalFirewallIntegration.sol

@@ -6,6 +6,7 @@ import {CheckpointExecutor} from "../CheckpointExecutor.sol";
 import {ExternalFirewall} from "../ExternalFirewall.sol";
 import {ISecurityValidator} from "../interfaces/ISecurityValidator.sol";
 import {FirewallAccess} from "../FirewallAccess.sol";
+import {FirewallRouter} from "../FirewallRouter.sol";
 import {IExternalFirewall} from "../interfaces/IExternalFirewall.sol";
 import {ICheckpointHook} from "../interfaces/ICheckpointHook.sol";
 import {
@@ -35,6 +36,7 @@ contract ProtectedContract is CheckpointExecutor {
 /// for firewall integration.
 contract Deployer {
     event DeployedFirewall(ExternalFirewall firewall);
+    event DeployedFirewallRouter(FirewallRouter firewallRouter);
     event DeployedProtectedContract(ProtectedContract protectedContract);
 
     function deploy(
@@ -50,7 +52,11 @@ contract Deployer {
             new ExternalFirewall(validator, ICheckpointHook(address(0)), attesterControllerId, firewallAccess);
         emit DeployedFirewall(externalFirewall);
 
-        ProtectedContract protectedContract = new ProtectedContract(externalFirewall);
+        /// deploy a router for firewall upgradeability
+        FirewallRouter firewallRouter = new FirewallRouter(externalFirewall, firewallAccess);
+        emit DeployedFirewallRouter(firewallRouter);
+
+        ProtectedContract protectedContract = new ProtectedContract(firewallRouter);
         emit DeployedProtectedContract(protectedContract);
 
         /// will renounce later below
@@ -60,6 +66,7 @@ contract Deployer {
 
         /// let protected contract execute checkpoints on the external firewall
         firewallAccess.grantRole(CHECKPOINT_EXECUTOR_ROLE, address(protectedContract));
+        firewallAccess.grantRole(CHECKPOINT_EXECUTOR_ROLE, address(firewallRouter));
 
         /// set the trusted attester:
         /// this will be necessary when "foo()" receives an attested call later.