Use Ownable2Step

README.md

@@ -2,15 +2,28 @@
 
 Contracts for managing validator's rewards fees
 
-## How it works on a high-level
+## Overview
 
-- The repo contains 2 contracts: `FeeRewardsManager` and `RewardsCollector`
-- Fee manager contract `FeeRewardsManager` will be deployed once per environment
+- The repo contains 2 contracts: `FeeRewardsManager` and `RewardsCollector` and a library `CalculateAndSendRewards`
+- Fee manager contract `FeeRewardsManager` will be deployed once per environment.
 - `FeeRewardsManager` creates one `RewardsCollector` contract per withdrawal credentials (some users may have more than 1)
-- On creation `FeeRewardsManager` sets a default commission fee and has permission to change that fee
-- `RewardsCollector` address will be derived from `withdrawal credentials`
-- `RewardsCollector` address will be set as `fee_recipient` for customers validators and earn execution rewards
-- `collectRewards` function in `RewardsCollector` contract can be triggered to send rewards minus commission fee to withdrawal address
+- On creation `FeeRewardsManager` sets a default commission fee and has permission to change that fee.
+- `RewardsCollector` address will be derived from `withdrawal credentials`.
+- `RewardsCollector` address will be set as `fee_recipient` for customers validators and earn execution rewards.
+- `collectRewards` function in `RewardsCollector` contract can be triggered to send rewards minus commission fee to withdrawal .address.
+
+### `RewardsCollector` Contract
+
+- **Ownership**: This contract does not explicitly use an ownership model. Instead, it references a `parentContract`, the contract that deployed it, the `FeeRewardsManager` contract.
+- **withdrawalCredential**: A crucial address that is set upon contract deployment, determining where a portion of the fees are sent.
+- **feeNumerator**: A value determining the fee percentage, modifiable only by the `parentContract`.
+
+### `FeeRewardsManager` Contract
+
+- **Ownership**: Inherits from `Ownable2Step`, a variant of the OpenZeppelin `Ownable` contract, which provides a secure ownership model with a two-step transfer process to prevent accidental loss of ownership. The part that is receiving
+the ownership on the transfer must confirm it with a transaction.
+- **defaultFeeNumerator**: Set upon deployment and modifiable by the contract owner.
+- **Eth Withdrawal**: Only the owner can withdraw Eth from the contract.
 
 ## Walkthrough a normal execution
 

src/FeeRewardsManager.sol

@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: BSD-3-Clause
 pragma solidity ^0.8.13;
 
-import "@openzeppelin/contracts/access/Ownable.sol";
+import "@openzeppelin/contracts/access/Ownable2Step.sol";
 
 // We use a library for the `calculateRewards` function because the less code in
 // `RewardsCollector` the less expensive it it to deploy the collector contract.
@@ -86,7 +86,7 @@ contract RewardsCollector {
     }
 }
 
-contract FeeRewardsManager is Ownable {
+contract FeeRewardsManager is Ownable2Step {
     uint32 public defaultFeeNumerator;
 
     constructor(uint32 _defaultFeeNumerator) {

test/FeeRewardsManager.t.sol

@@ -200,4 +200,13 @@ contract FeeRewardsTest is Test {
         vm.expectRevert("Failed to send Ether back to withdrawal credential");
         RewardsCollector(payable(addr)).collectRewards();
     }
+
+    function testChangeOwnership() public {
+        feeRewardsManager.transferOwnership(address(0x105));
+        assertEq(feeRewardsManager.pendingOwner(), address(0x105));
+        vm.startPrank(address(0x105));
+        feeRewardsManager.acceptOwnership();
+        vm.stopPrank();
+        assertEq(feeRewardsManager.owner(), address(0x105));
+    }
 }