Delete old ValidatorManager, rm IValidatorManager reference in Common.sol

solidity/core/contracts/Common.sol

@@ -2,7 +2,6 @@
 pragma solidity >=0.6.11;
 
 // ============ Internal Imports ============
-import {IValidatorManager} from "../interfaces/IValidatorManager.sol";
 import {ICommon} from "../interfaces/ICommon.sol";
 // ============ External Imports ============
 import {OwnableUpgradeable} from "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
@@ -26,7 +25,7 @@ abstract contract Common is ICommon, OwnableUpgradeable {
     // The latest checkpointed root
     bytes32 public checkpointedRoot;
     // Address of ValidatorManager contract.
-    IValidatorManager public validatorManager;
+    address public validatorManager;
 
     // ============ Upgrade Gap ============
 
@@ -55,7 +54,7 @@ abstract contract Common is ICommon, OwnableUpgradeable {
      * @notice Ensures that function is called by the ValidatorManager contract
      */
     modifier onlyValidatorManager() {
-        require(msg.sender == address(validatorManager), "!validatorManager");
+        require(msg.sender == validatorManager, "!validatorManager");
         _;
     }
 
@@ -73,7 +72,7 @@ abstract contract Common is ICommon, OwnableUpgradeable {
     {
         // initialize owner
         __Ownable_init();
-        _setValidatorManager(IValidatorManager(_validatorManager));
+        _setValidatorManager(_validatorManager);
     }
 
     // ============ External Functions ============
@@ -86,7 +85,7 @@ abstract contract Common is ICommon, OwnableUpgradeable {
      * @param _validatorManager the new ValidatorManager contract
      */
     function setValidatorManager(address _validatorManager) external onlyOwner {
-        _setValidatorManager(IValidatorManager(_validatorManager));
+        _setValidatorManager(_validatorManager);
     }
 
     /**
@@ -110,15 +109,13 @@ abstract contract Common is ICommon, OwnableUpgradeable {
      * @notice Set the ValidatorManager
      * @param _validatorManager Address of the ValidatorManager
      */
-    function _setValidatorManager(IValidatorManager _validatorManager)
-        internal
-    {
+    function _setValidatorManager(address _validatorManager) internal {
         require(
-            Address.isContract(address(_validatorManager)),
+            Address.isContract(_validatorManager),
             "!contract validatorManager"
         );
         validatorManager = _validatorManager;
-        emit NewValidatorManager(address(_validatorManager));
+        emit NewValidatorManager(_validatorManager);
     }
 
     /**

solidity/core/contracts/ValidatorManager.sol

@@ -1,131 +0,0 @@
-// SPDX-License-Identifier: MIT OR Apache-2.0
-pragma solidity >=0.6.11;
-
-// ============ Internal Imports ============
-import {IValidatorManager} from "../interfaces/IValidatorManager.sol";
-import {Outbox} from "./Outbox.sol";
-// ============ External Imports ============
-import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
-import {ECDSA} from "@openzeppelin/contracts/cryptography/ECDSA.sol";
-
-/**
- * @title ValidatorManager
- * @author Celo Labs Inc.
- * @notice MVP version of contract that will manage Validator selection and
- * rotataion.
- */
-contract ValidatorManager is IValidatorManager, Ownable {
-    // Mapping of domain -> validator address.
-    mapping(uint32 => address) public validators;
-
-    // ============ Events ============
-
-    /**
-     * @notice Emitted when a validator is enrolled
-     * @param domain The domain for which the validator is being enrolled
-     * @param validator The address of the validator
-     */
-    event ValidatorEnrolled(uint32 indexed domain, address indexed validator);
-
-    /**
-     * @notice Emitted when proof of an improper checkpoint is submitted,
-     * which sets the contract to FAILED state
-     * @param root Root of the improper checkpoint
-     * @param index Index of the improper checkpoint
-     * @param signature Signature on `root` and `index`
-     */
-    event ImproperCheckpoint(
-        address indexed outbox,
-        uint32 indexed domain,
-        address indexed validator,
-        bytes32 root,
-        uint256 index,
-        bytes signature
-    );
-
-    // ============ Constructor ============
-
-    constructor() Ownable() {}
-
-    // ============ External Functions ============
-
-    /**
-     * @notice Enroll a validator for the given domain
-     * @dev only callable by trusted owner
-     * @param _domain The domain for which the validator is being set
-     * @param _validator The address of the validator
-     */
-    function enrollValidator(uint32 _domain, address _validator)
-        external
-        onlyOwner
-    {
-        validators[_domain] = _validator;
-        emit ValidatorEnrolled(_domain, _validator);
-    }
-
-    /**
-     * @notice Check if an Checkpoint is an Improper Checkpoint;
-     * if so, set the provided Outbox contract to FAILED state.
-     *
-     * An Improper Checkpoint is an checkpoint that was not previously checkpointed.
-     * @param _outbox Address of the Outbox contract to set to FAILED.
-     * @param _root Merkle root of the improper checkpoint
-     * @param _index Index root of the improper checkpoint
-     * @param _signature Validator signature on `_root` and `_index`
-     * @return TRUE if checkpoint was an Improper Checkpoint (implying Validator was slashed)
-     */
-    function improperCheckpoint(
-        address _outbox,
-        bytes32 _root,
-        uint256 _index,
-        bytes calldata _signature
-    ) external returns (bool) {
-        uint32 _domain = Outbox(_outbox).localDomain();
-        require(
-            isValidatorSignature(_domain, _root, _index, _signature),
-            "!validator sig"
-        );
-        require(Outbox(_outbox).checkpoints(_root) != _index, "!improper");
-        Outbox(_outbox).fail();
-        emit ImproperCheckpoint(
-            _outbox,
-            _domain,
-            validators[_domain],
-            _root,
-            _index,
-            _signature
-        );
-        return true;
-    }
-
-    // ============ Public Functions ============
-
-    /**
-     * @notice Checks that signature was signed by Validator
-     * @param _domain Domain of Outbox contract
-     * @param _root Merkle root
-     * @param _index Corresponding leaf index
-     * @param _signature Signature on `_root` and `_index`
-     * @return TRUE iff signature is valid signed by validator
-     **/
-    function isValidatorSignature(
-        uint32 _domain,
-        bytes32 _root,
-        uint256 _index,
-        bytes calldata _signature
-    ) public view override returns (bool) {
-        bytes32 _digest = keccak256(
-            abi.encodePacked(domainHash(_domain), _root, _index)
-        );
-        _digest = ECDSA.toEthSignedMessageHash(_digest);
-        return (ECDSA.recover(_digest, _signature) == validators[_domain]);
-    }
-
-    /**
-     * @notice Hash of domain concatenated with "ABACUS"
-     * @param _domain the domain to hash
-     */
-    function domainHash(uint32 _domain) public pure returns (bytes32) {
-        return keccak256(abi.encodePacked(_domain, "ABACUS"));
-    }
-}

solidity/core/contracts/test/TestOutbox.sol

@@ -3,7 +3,6 @@ pragma solidity >=0.6.11;
 
 // ============ Internal Imports ============
 import "../Outbox.sol";
-import {IValidatorManager} from "../../interfaces/IValidatorManager.sol";
 
 contract TestOutbox is Outbox {
     constructor(uint32 _localDomain) Outbox(_localDomain) {} // solhint-disable-line no-empty-blocks
@@ -21,6 +20,6 @@ contract TestOutbox is Outbox {
      * @param _validatorManager Address of the ValidatorManager
      */
     function testSetValidatorManager(address _validatorManager) external {
-        validatorManager = IValidatorManager(_validatorManager);
+        validatorManager = _validatorManager;
     }
 }