Report mvp

packages/contracts/contracts/AttestationCollector.sol

@@ -63,8 +63,8 @@ contract AttestationCollector is AuthManager, OwnableUpgradeable {
  ▏*║ EXTERNAL FUNCTIONS ║*▕
  \*╚══════════════════════════════════════════════════════════════════════╝*/
 
- function submitAttestation(address _updater, bytes memory _attestation) external {
- bytes29 _view = _checkUpdaterAuth(_updater, _attestation);
+ function submitAttestation(bytes memory _attestation) external {
+ (address _updater, bytes29 _view) = _checkUpdaterAuth(_attestation);
  _storeAttestation(_view);
  emit AttestationSubmitted(_updater, _attestation);
  }

packages/contracts/contracts/Home.sol

@@ -4,8 +4,10 @@ pragma solidity 0.8.13;
 // ============ Internal Imports ============
 import { Version0 } from "./Version0.sol";
 import { UpdaterStorage } from "./UpdaterStorage.sol";
-import { AuthManager } from "./auth/AuthManager.sol";
+import { ReportHub } from "./auth/ReportHub.sol";
 import { Attestation } from "./libs/Attestation.sol";
+import { Report } from "./libs/Report.sol";
+import { TypedMemView } from "./libs/TypedMemView.sol";
 import { QueueLib } from "./libs/Queue.sol";
 import { MerkleLib } from "./libs/Merkle.sol";
 import { Header } from "./libs/Header.sol";
@@ -28,10 +30,12 @@ import { Address } from "@openzeppelin/contracts/utils/Address.sol";
  * Accepts submissions of fraudulent signatures
  * by the Updater and slashes the Updater in this case.
  */
-contract Home is Version0, MerkleTreeManager, UpdaterStorage, AuthManager {
+contract Home is Version0, MerkleTreeManager, UpdaterStorage, ReportHub {
  // ============ Libraries ============
 
  using Attestation for bytes29;
+ using Report for bytes29;
+ using TypedMemView for bytes29;
  using MerkleLib for MerkleLib.Tree;
 
  using Tips for bytes;
@@ -92,20 +96,32 @@ contract Home is Version0, MerkleTreeManager, UpdaterStorage, AuthManager {
  );
 
  /**
- * @notice Emitted when proof of an improper attestation is submitted,
+ * @notice Emitted when proof of an invalid attestation is submitted,
  * which sets the contract to FAILED state
- * @param updater Updater who signed improper attestation
+ * @param updater Updater who signed invalid attestation
  * @param attestation Attestation data and signature
  */
- event ImproperAttestation(address updater, bytes attestation);
+ event InvalidAttestation(address updater, bytes attestation);
+
+ /**
+ * @notice Emitted when proof of an invalid fraud report is submitted
+ * @param watchtower Watchtower who signed invalid fraud report
+ * @param report Report data and signature
+ */
+ event InvalidReport(address watchtower, bytes report);
 
  /**
  * @notice Emitted when the Updater is slashed
- * (should be paired with ImproperUpdater or DoubleUpdate event)
- * @param updater The address of the updater
- * @param reporter The address of the entity that reported the updater misbehavior
+ * (should be paired with InvalidAttestation event)
+ * @param updater The address of the updater
+ * @param reporter The address of the entity that reported the updater misbehavior
+ * @param watchtower The address of watchtower that signed the fraud report
  */
- event UpdaterSlashed(address indexed updater, address indexed reporter);
+ event UpdaterSlashed(
+ address indexed updater,
+ address indexed reporter,
+ address indexed watchtower
+ );
 
  /**
  * @notice Emitted when the UpdaterManager contract is changed
@@ -119,10 +135,10 @@ contract Home is Version0, MerkleTreeManager, UpdaterStorage, AuthManager {
 
  // ============ Initializer ============
 
- function initialize(IUpdaterManager _updaterManager) public initializer {
+ function initialize(IUpdaterManager _updaterManager, address _watchtower) public initializer {
  // initialize queue, set Updater Manager, and initialize
  _setUpdaterManager(_updaterManager);
- __SynapseBase_initialize(updaterManager.updater());
+ __SynapseBase_initialize(updaterManager.updater(), _watchtower);
  state = States.Active;
  }
 
@@ -238,56 +254,59 @@ contract Home is Version0, MerkleTreeManager, UpdaterStorage, AuthManager {
  return _domainHash(localDomain);
  }
 
- // ============ Public Functions ============
+ // ============ Internal Functions ============
 
  /**
- * @notice Check if an Attestation is an Improper Attestation;
- * if so, slash the Updater and set the contract to FAILED state.
+ * @notice Check if a reported Attestation is an Invalid Attestation;
+ * if so, slash the Notary and set the contract to FAILED state.
  *
- * An Improper Attestation is a (_nonce, _root) update that doesn't correspond with
+ * An Invalid Attestation is a (_nonce, _root) attestation that doesn't correspond with
  * the historical state of Home contract. Either of those needs to be true:
  * - _nonce is higher than current nonce (no root exists for this nonce)
  * - _root is not equal to the historical root of _nonce
  * This would mean that message(s) that were not truly
  * dispatched on Home were falsely included in the signed root.
  *
- * An Improper Attestation will only be accepted as valid by the Replica
- * If an Improper Attestation is attempted on Home,
- * the Updater will be slashed immediately.
- * If an Improper Attestation is submitted to the Replica,
- * it should be relayed to the Home contract using this function
- * in order to slash the Updater with an Improper Attestation.
+ * An Invalid Attestation will only be accepted as valid by the Replica
+ * If an Invalid Attestation is attempted on Home, the Notary will be slashed immediately.
+ * If an Invalid Attestation is submitted to the Replica, a Guard should generate a Report.
+ * This Report should be submitted to the Home contract using this function
+ * in order to slash the Notary with an Invalid Attestation.
  *
- * @dev Reverts (and doesn't slash updater) if signature is invalid or
- * update not current
- * @param _updater Updater who signed the attestation
- * @param _attestation Attestation data and signature
- * @return TRUE if update was an Improper Attestation (implying Updater was slashed)
+ * @dev Both Notary and Guard signatures
+ * have been checked at this point (see ReportHub.sol).
+ *
+ * @param _guard Guard address
+ * @param _notary Notary address
+ * @param _attestationView Memory view over reported Attestation
+ * @param _report Payload with Report data and signature
+ * @return TRUE if attestation was an Invalid Attestation (implying Notary was slashed)
  */
- function improperAttestation(address _updater, bytes memory _attestation)
- public
- notFailed
- returns (bool)
- {
-  // This will revert if signature is not valid
- bytes29 _view = _checkUpdaterAuth(_updater, _attestation);
- uint32 _nonce = _view.attestationNonce();
- bytes32 _root = _view.attestationRoot();
- // Check if nonce is valid, if not => update is fraud
+ function _handleReport(
+ address _guard,
+ address _notary,
+ bytes29 _attestationView,
+  bytes memory _report
+ ) internal override notFailed returns (bool) {
+ // Get merkle state from the attestation
+ uint32 _nonce = _attestationView.attestationNonce();
+ bytes32 _root = _attestationView.attestationRoot();
+ // Check if `_nonce` exists, if not => attestation is fraud
  if (_nonce < historicalRoots.length) {
  if (_root == historicalRoots[_nonce]) {
- // Signed (nonce, root) update is valid
+ // (nonce, root) corresponds with the historical merkle state of Home.
+ // Means Notary attestation is valid, while Guard report is invalid.
+ // TODO: slash Guard for signing an invalid fraud report
+ emit InvalidReport(_guard, _report);
  return false;
  }
- // Signed root is not the same as the historical one => update is fraud
+ // `_root` doesn't match historical root for `_nonce` => attestation is fraud
  }
- _fail();
- emit ImproperAttestation(_updater, _attestation);
+ _fail(_guard);
+ emit InvalidAttestation(_notary, _attestationView.clone());
  return true;
  }
 
- // ============ Internal Functions ============
-
  /**
  * @notice Set the UpdaterManager
  * @param _updaterManager Address of the UpdaterManager
@@ -300,14 +319,14 @@ contract Home is Version0, MerkleTreeManager, UpdaterStorage, AuthManager {
 
  /**
  * @notice Slash the Updater and set contract state to FAILED
- * @dev Called when fraud is proven (Improper Update or Double Update)
+ * @dev Called when fraud is proven (Invalid Attestation)
  */
- function _fail() internal {
+ function _fail(address _watchtower) internal {
  // set contract to FAILED
  state = States.Failed;
  // slash Updater
  updaterManager.slashUpdater(payable(msg.sender));
- emit UpdaterSlashed(updater, msg.sender);
+ emit UpdaterSlashed(updater, msg.sender, _watchtower);
  }
 
  /**
@@ -336,8 +355,8 @@ contract Home is Version0, MerkleTreeManager, UpdaterStorage, AuthManager {
  return _updater == updater;
  }
 
- function _isWatchtower(address) internal pure override returns (bool) {
- return false;
+ function _isWatchtower(address _watchtower) internal view override returns (bool) {
+ return _watchtower == watchtower;
  }
 
  /**

packages/contracts/contracts/ReplicaManager.sol

@@ -3,8 +3,9 @@ pragma solidity 0.8.13;
 
 // ============ Internal Imports ============
 import { UpdaterStorage } from "./UpdaterStorage.sol";
-import { AuthManager } from "./auth/AuthManager.sol";
+import { ReportHub } from "./auth/ReportHub.sol";
 import { Attestation } from "./libs/Attestation.sol";
+import { Report } from "./libs/Report.sol";
 import { Version0 } from "./Version0.sol";
 import { ReplicaLib } from "./libs/Replica.sol";
 import { MerkleLib } from "./libs/Merkle.sol";
@@ -22,14 +23,15 @@ import { TypedMemView } from "./libs/TypedMemView.sol";
  * @notice Track root updates on Home,
  * prove and dispatch messages to end recipients.
  */
-contract ReplicaManager is Version0, UpdaterStorage, AuthManager {
+contract ReplicaManager is Version0, UpdaterStorage, ReportHub {
  // ============ Libraries ============
 
  using ReplicaLib for ReplicaLib.Replica;
  using MerkleLib for MerkleLib.Tree;
  using Message for bytes;
  using TypedMemView for bytes29;
  using Attestation for bytes29;
+ using Report for bytes29;
  using Message for bytes29;
  using Header for bytes29;
 
@@ -76,6 +78,13 @@ contract ReplicaManager is Version0, UpdaterStorage, AuthManager {
  uint256 newConfirmAt
  );
 
+ event UpdaterBlacklisted(
+ address indexed updater,
+ address indexed reporter,
+ address indexed watchtower,
+ bytes report
+ );
+
  // ============ Constructor ============
 
  constructor(uint32 _localDomain) UpdaterStorage(_localDomain) {}
@@ -93,8 +102,12 @@ contract ReplicaManager is Version0, UpdaterStorage, AuthManager {
  * @param _remoteDomain The domain of the Home contract this follows
  * @param _updater The EVM id of the updater
  */
- function initialize(uint32 _remoteDomain, address _updater) public initializer {
- __SynapseBase_initialize(_updater);
+ function initialize(
+ uint32 _remoteDomain,
+ address _updater,
+ address _watchtower
+ ) public initializer {
+ __SynapseBase_initialize(_updater, _watchtower);
  // set storage variables
  entered = 1;
  activeReplicas[_remoteDomain] = _createReplica(_remoteDomain);
@@ -133,11 +146,10 @@ contract ReplicaManager is Version0, UpdaterStorage, AuthManager {
  * marks root's allowable confirmation time, and emits an `Update` event.
  * @dev Reverts if update doesn't build off latest committedRoot
  * or if signature is invalid.
- * @param _updater Updater who signer the attestation
  * @param _attestation Attestation data and signature
  */
- function submitAttestation(address _updater, bytes memory _attestation) external {
- bytes29 _view = _checkUpdaterAuth(_updater, _attestation);
+ function submitAttestation(bytes memory _attestation) external {
+ (, bytes29 _view) = _checkUpdaterAuth(_attestation);
  uint32 remoteDomain = _view.attestationDomain();
  require(remoteDomain != localDomain, "Update refers to local chain");
  uint32 nonce = _view.attestationNonce();
@@ -340,8 +352,8 @@ contract ReplicaManager is Version0, UpdaterStorage, AuthManager {
  return _updater == updater;
  }
 
- function _isWatchtower(address) internal pure override returns (bool) {
- return false;
+ function _isWatchtower(address _watchtower) internal view override returns (bool) {
+ return _watchtower == watchtower;
  }
 
  function _checkForSystemMessage(bytes32 _recipient) internal view returns (address recipient) {
@@ -359,7 +371,37 @@ contract ReplicaManager is Version0, UpdaterStorage, AuthManager {
  }
  }
 
+ /**
+ * @notice Applies submitted Report to blacklist reported Notary, and all roots signed by this Notary.
+ * An honest Notary is incentivized to sign a valid Attestation to collect tips
+ * from the pending messages, which prevents downtime caused by root blacklisting.
+ *
+ * @dev Both Notary and Guard signatures
+ * have been checked at this point (see ReportHub.sol).
+ *
+ * @param _guard Guard address
+ * @param _notary Notary address
+ * @param _report Report payload
+ * @return notaryBlacklisted TRUE if Notary was blacklisted as a result, FALSE if Notary has been blacklisted earlier.
+ */
+ function _handleReport(
+ address _guard,
+ address _notary,
+ bytes29,
+ bytes memory _report
+ ) internal override returns (bool notaryBlacklisted) {
+ notaryBlacklisted = _blacklistNotary(_notary);
+ if (notaryBlacklisted) {
+ emit UpdaterBlacklisted(_notary, msg.sender, _guard, _report);
+ }
+ }
+
  function _storeTips(bytes29 _tips) internal virtual {
  // TODO: implement storing & claiming logic
  }
+
+ function _blacklistNotary(address _notary) internal returns (bool) {
+ // TODO: implement actual blacklisting
+ return _notary == updater;
+ }
 }

packages/contracts/contracts/UpdaterStorage.sol

@@ -26,6 +26,8 @@ abstract contract UpdaterStorage is Initializable, OwnableUpgradeable {
 
  // Address of bonded Updater
  address public updater;
+ // Address of bonded Watchtower
+ address public watchtower;
 
  ISystemMessenger public systemMessenger;
 
@@ -67,9 +69,13 @@ abstract contract UpdaterStorage is Initializable, OwnableUpgradeable {
 
  // ============ Initializer ============
 
- function __SynapseBase_initialize(address _updater) internal onlyInitializing {
+ function __SynapseBase_initialize(address _updater, address _watchtower)
+ internal
+ onlyInitializing
+ {
  __Ownable_init();
  _setUpdater(_updater);
+ watchtower = _watchtower;
  }
 
  // ============ Modifiers ============