feat: whitelist for vanilla staking (#698)

Author: shaspitz

contracts-abi/abi/VanillaRegistry.abi

@@ -379,6 +379,19 @@
     ],
     "stateMutability": "view"
   },
+  {
+    "type": "function",
+    "name": "removeWhitelistedStakers",
+    "inputs": [
+      {
+        "name": "stakers",
+        "type": "address[]",
+        "internalType": "address[]"
+      }
+    ],
+    "outputs": [],
+    "stateMutability": "nonpayable"
+  },
   {
     "type": "function",
     "name": "renounceOwnership",
@@ -633,6 +646,38 @@
     "outputs": [],
     "stateMutability": "payable"
   },
+  {
+    "type": "function",
+    "name": "whitelistStakers",
+    "inputs": [
+      {
+        "name": "stakers",
+        "type": "address[]",
+        "internalType": "address[]"
+      }
+    ],
+    "outputs": [],
+    "stateMutability": "nonpayable"
+  },
+  {
+    "type": "function",
+    "name": "whitelistedStakers",
+    "inputs": [
+      {
+        "name": "staker",
+        "type": "address",
+        "internalType": "address"
+      }
+    ],
+    "outputs": [
+      {
+        "name": "whitelisted",
+        "type": "bool",
+        "internalType": "bool"
+      }
+    ],
+    "stateMutability": "view"
+  },
   {
     "type": "function",
     "name": "withdraw",
@@ -941,6 +986,44 @@
     ],
     "anonymous": false
   },
+  {
+    "type": "event",
+    "name": "StakerRemovedFromWhitelist",
+    "inputs": [
+      {
+        "name": "msgSender",
+        "type": "address",
+        "indexed": true,
+        "internalType": "address"
+      },
+      {
+        "name": "staker",
+        "type": "address",
+        "indexed": false,
+        "internalType": "address"
+      }
+    ],
+    "anonymous": false
+  },
+  {
+    "type": "event",
+    "name": "StakerWhitelisted",
+    "inputs": [
+      {
+        "name": "msgSender",
+        "type": "address",
+        "indexed": true,
+        "internalType": "address"
+      },
+      {
+        "name": "staker",
+        "type": "address",
+        "indexed": false,
+        "internalType": "address"
+      }
+    ],
+    "anonymous": false
+  },
   {
     "type": "event",
     "name": "TotalStakeWithdrawn",
@@ -1188,6 +1271,17 @@
       }
     ]
   },
+  {
+    "type": "error",
+    "name": "SenderIsNotWhitelistedStaker",
+    "inputs": [
+      {
+        "name": "sender",
+        "type": "address",
+        "internalType": "address"
+      }
+    ]
+  },
   {
     "type": "error",
     "name": "SenderIsNotWithdrawalAddress",
@@ -1250,6 +1344,28 @@
       }
     ]
   },
+  {
+    "type": "error",
+    "name": "StakerAlreadyWhitelisted",
+    "inputs": [
+      {
+        "name": "staker",
+        "type": "address",
+        "internalType": "address"
+      }
+    ]
+  },
+  {
+    "type": "error",
+    "name": "StakerNotWhitelisted",
+    "inputs": [
+      {
+        "name": "staker",
+        "type": "address",
+        "internalType": "address"
+      }
+    ]
+  },
   {
     "type": "error",
     "name": "TransferToRecipientFailed",

contracts-abi/clients/VanillaRegistry/VanillaRegistry.go

@@ -48,6 +48,12 @@ interface IVanillaRegistry {
     /// @dev Event emitted when the slashing payout period blocks parameter is set.
     event SlashingPayoutPeriodBlocksSet(address indexed msgSender, uint256 newSlashingPayoutPeriodBlocks);
 
+    /// @dev Event emitted when a staker is whitelisted.
+    event StakerWhitelisted(address indexed msgSender, address staker);
+
+    /// @dev Event emitted when a staker is removed from the whitelist.
+    event StakerRemovedFromWhitelist(address indexed msgSender, address staker);
+
     error ValidatorRecordMustExist(bytes valBLSPubKey);
     error ValidatorRecordMustNotExist(bytes valBLSPubKey);
     error ValidatorCannotBeUnstaking(bytes valBLSPubKey);
@@ -70,6 +76,9 @@ interface IVanillaRegistry {
     error SlashReceiverMustBeSet();
     error UnstakePeriodMustBePositive();
     error SlashingPayoutPeriodMustBePositive();
+    error SenderIsNotWhitelistedStaker(address sender);
+    error StakerAlreadyWhitelisted(address staker);
+    error StakerNotWhitelisted(address staker);
 
     /// @dev Initializes the contract with the provided parameters.
     function initialize(

contracts/contracts/interfaces/IVanillaRegistry.sol

@@ -31,6 +31,12 @@ contract VanillaRegistry is IVanillaRegistry, VanillaRegistryStorage,
         _;
     }
 
+    /// @dev Modifier to confirm the sender is whitelisted.
+    modifier onlyWhitelistedStaker() {
+        require(whitelistedStakers[msg.sender], IVanillaRegistry.SenderIsNotWhitelistedStaker(msg.sender));
+        _;
+    }
+
     /// @dev See https://docs.openzeppelin.com/upgrades-plugins/1.x/writing-upgradeable#initializing_the_implementation_contract
     /// @custom:oz-upgrades-unsafe-allow constructor
     constructor() {
@@ -69,7 +75,7 @@ contract VanillaRegistry is IVanillaRegistry, VanillaRegistryStorage,
      * @param blsPubKeys The validator BLS public keys to stake.
      */
     function stake(bytes[] calldata blsPubKeys) external payable
-        onlyValidBLSPubKeys(blsPubKeys) whenNotPaused() {
+        onlyValidBLSPubKeys(blsPubKeys) onlyWhitelistedStaker() whenNotPaused() {
         _stake(blsPubKeys, msg.sender);
     }
 
@@ -90,7 +96,7 @@ contract VanillaRegistry is IVanillaRegistry, VanillaRegistryStorage,
      * @dev A staking entry must already exist for each provided BLS pubkey.
      * @param blsPubKeys The BLS public keys to add stake to.
      */
-    function addStake(bytes[] calldata blsPubKeys) external payable whenNotPaused() {
+    function addStake(bytes[] calldata blsPubKeys) external payable onlyWhitelistedStaker() whenNotPaused() {
         _addStake(blsPubKeys);
     }
 
@@ -180,6 +186,26 @@ contract VanillaRegistry is IVanillaRegistry, VanillaRegistryStorage,
         FeePayout.transferToRecipient(slashingFundsTracker);
     }
 
+    /// @dev Enables the owner to whitelist stakers.
+    function whitelistStakers(address[] calldata stakers) external onlyOwner {
+        uint256 len = stakers.length;
+        for (uint256 i = 0; i < len; ++i) {
+            require(!whitelistedStakers[stakers[i]], IVanillaRegistry.StakerAlreadyWhitelisted(stakers[i]));
+            whitelistedStakers[stakers[i]] = true;
+            emit StakerWhitelisted(msg.sender, stakers[i]);
+        }
+    }
+
+    /// @dev Enables the owner to remove stakers from the whitelist.
+    function removeWhitelistedStakers(address[] calldata stakers) external onlyOwner {
+        uint256 len = stakers.length;
+        for (uint256 i = 0; i < len; ++i) {
+            require(whitelistedStakers[stakers[i]], IVanillaRegistry.StakerNotWhitelisted(stakers[i]));
+            whitelistedStakers[stakers[i]] = false;
+            emit StakerRemovedFromWhitelist(msg.sender, stakers[i]);
+        }
+    }
+
     /// @dev Returns true if a validator is considered "opted-in" to mev-commit via this registry.
     function isValidatorOptedIn(bytes calldata valBLSPubKey) external view returns (bool) {
         return _isValidatorOptedIn(valBLSPubKey);

contracts/contracts/validator-registry/VanillaRegistry.sol

@@ -26,6 +26,9 @@ contract VanillaRegistryStorage {
     /// @dev Mapping of withdrawal addresses to claimable ETH that was force withdrawn by the owner.
     mapping(address withdrawalAddress => uint256 amountToClaim) public forceWithdrawnFunds;
 
+    /// @dev Mapping of staker addresses to whether they are whitelisted.
+    mapping(address staker => bool whitelisted) public whitelistedStakers;
+
     /// @dev See https://docs.openzeppelin.com/upgrades-plugins/1.x/writing-upgradeable#storage-gaps
     uint256[48] private __gap;
 }