feat: block timelocked multisig during liveness disruption (#66)

packages/protocol/contracts/layer1/based/ITaikoL1.sol

@@ -98,6 +98,11 @@ interface ITaikoL1 {
     /// @return The prover's address. If the block is not verified yet, address(0) will be returned.
     function getVerifiedBlockProver(uint64 _blockId) external view returns (address);
 
+    /// @notice Returns the timestamp of the last verification.
+    /// @return The timestamp of the last verification.
+    // Surge: Returns `lastVerificationTimestamp` added as stage-2 requirements for surge
+    function getLastVerificationTimestamp() external view returns(uint256);
+
     /// @notice Gets the configuration of the TaikoL1 contract.
     /// @return Config struct containing configuration parameters.
     // Surge: switch to `view` to allow for dynamic chainid

packages/protocol/contracts/layer1/based/LibVerifying.sol

@@ -159,6 +159,9 @@ library LibVerifying {
             }
 
             if (local.numBlocksVerified != 0) {
+                // Surge: Update last verification timestamp if a block has been verified
+                _state.lastVerificationTimestamp = block.timestamp;
+
                 uint64 lastVerifiedBlockId = local.b.lastVerifiedBlockId + local.numBlocksVerified;
                 local.slot = lastVerifiedBlockId % _config.blockRingBufferSize;
 

packages/protocol/contracts/layer1/based/TaikoData.sol

@@ -235,6 +235,13 @@ library TaikoData {
         SlotA slotA; // slot 5
         SlotB slotB; // slot 6
         mapping(address account => uint256 bond) bondBalance;
-        uint256[43] __gap;
+
+        // Surge: Record the timestamp at which the last block verification happened to enforce
+        // stage-2 rollup requirement of blocking all owner operations if no block verified
+        // in the last 2 hours
+        uint256 lastVerificationTimestamp; // Slot 7
+
+        // Surge: Gap reduced by 1
+        uint256[42] __gap;
     }
 }

packages/protocol/contracts/layer1/based/TaikoL1.sol

@@ -289,6 +289,12 @@ contract TaikoL1 is EssentialContract, ITaikoL1, TaikoEvents {
         state.slotB.lastUnpausedAt = uint64(block.timestamp);
     }
 
+    /// @inheritdoc ITaikoL1
+    // Surge: Stage-2 requirement
+    function getLastVerificationTimestamp() external view returns(uint256) {
+        return state.lastVerificationTimestamp;
+    }
+
     /// @inheritdoc ITaikoL1
     // Surge: switch to `view` to allow for dynamic chainid
     function getConfig() public view virtual returns (TaikoData.Config memory) {

packages/protocol/contracts/layer1/surge/SurgeTimelockController.sol

@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.24;
+
+import "../based/ITaikoL1.sol";
+import "@openzeppelin/contracts/governance/TimelockController.sol";
+
+/// @title SurgeTimelockController
+/// @dev Staisfies stage-2 rollup requirements by blocking executions if a block 
+/// has not been verified in a while. 
+/// @custom:security-contact [email protected]
+contract SurgeTimelockedController is TimelockController {
+    /// @notice Address of taiko's inbox contract
+    ITaikoL1 internal taikoL1;
+
+    error ALREADY_INITIALIZED();
+    error LIVENESS_DISRUPTED();
+
+    constructor(uint256 minDelay, address[] memory proposers, address[] memory executors, address admin) TimelockController(minDelay, proposers, executors, admin) {}
+
+    function init(address _taikoL1) external {
+        if(address(taikoL1) != address(0)) {
+            revert ALREADY_INITIALIZED();
+        }
+        taikoL1 = ITaikoL1(_taikoL1);
+    }
+
+    function execute(
+        address target,
+        uint256 value,
+        bytes calldata payload,
+        bytes32 predecessor,
+        bytes32 salt
+    ) public payable override onlyRoleOrOpenRole(EXECUTOR_ROLE) {
+        if(_isLivenessDisrupted()) { 
+            revert LIVENESS_DISRUPTED();
+        }
+
+        super.execute(target, value, payload, predecessor, salt);
+    }
+
+    function executeBatch(
+        address[] calldata targets,
+        uint256[] calldata values,
+        bytes[] calldata payloads,
+        bytes32 predecessor,
+        bytes32 salt
+    ) public payable override onlyRoleOrOpenRole(EXECUTOR_ROLE) {
+        if(_isLivenessDisrupted()) { 
+            revert LIVENESS_DISRUPTED();
+        }
+
+        super.executeBatch(targets, values, payloads, predecessor, salt);
+    }
+
+    /// @dev Returns `true` if an L2 block has not been verified in the last 1 day
+    function _isLivenessDisrupted() internal view returns(bool) {
+        uint256 lastVerificationTimestamp = taikoL1.getLastVerificationTimestamp();
+        return (block.timestamp - lastVerificationTimestamp) > 1 days;
+    }
+}

packages/protocol/script/layer1/surge/DeploySurgeOnL1.s.sol

@@ -2,7 +2,6 @@
 pragma solidity ^0.8.24;
 
 import "@openzeppelin/contracts/utils/Strings.sol";
-import "@openzeppelin/contracts/governance/TimelockController.sol";
 import "@risc0/contracts/groth16/RiscZeroGroth16Verifier.sol";
 import { SP1Verifier as SuccinctVerifier } from "@sp1-contracts/src/v4.0.0-rc.3/SP1VerifierPlonk.sol";
 
@@ -21,6 +20,7 @@ import "src/shared/tokenvault/BridgedERC721.sol";
 import "src/shared/tokenvault/ERC1155Vault.sol";
 import "src/shared/tokenvault/ERC20Vault.sol";
 import "src/shared/tokenvault/ERC721Vault.sol";
+import "src/layer1/surge/SurgeTimelockController.sol";
 import "src/layer1/automata-attestation/AutomataDcapV3Attestation.sol";
 import "src/layer1/automata-attestation/lib/PEMCertChainLib.sol";
 import "src/layer1/automata-attestation/utils/SigVerifyLib.sol";
@@ -72,7 +72,7 @@ contract DeploySurgeOnL1 is DeployCapability {
 
         uint256 timelockPeriod = uint64(vm.envUint("TIMELOCK_PERIOD"));
         address timelockController = address(
-            new TimelockController(timelockPeriod, proposers, executors, address(0))
+            new SurgeTimelockedController(timelockPeriod, proposers, executors, address(0))
         );
         address contractOwner = timelockController;
 
@@ -103,6 +103,8 @@ contract DeploySurgeOnL1 is DeployCapability {
         );
         addressNotNull(taikoL1Addr, "taikoL1Addr");
 
+        SurgeTimelockedController(payable(timelockController)).init(taikoL1Addr);
+
         SignalService(signalServiceAddr).authorize(taikoL1Addr, true);
 
         console2.log("------------------------------------------");