Hacken audit fixes

Makefile

@@ -20,10 +20,13 @@ install	        :; forge install foundry-rs/forge-std --no-commit && \
                    forge install smartcontractkit/chainlink-brownie-contracts --no-commit && \
                    forge install OpenZeppelin/openzeppelin-community-contracts --no-commit
 .PHONY: test
-test          	:; forge test
-test-vvv        :; forge test -vvv
-test-gasreport 	:; forge test --gas-report
-test-fork       :; forge test --fork-url ${ETH_RPC_URL} -vvv
+test          	:	clean
+					forge test
+test-vvv        :	clean
+					forge test -vvv
+test-gasreport 	:	clean
+					forge test --gas-report
+test-fork       :;	forge test --fork-url ${ETH_RPC_URL} -vvv
 .PHONY: coverage
 coverage        :; mkdir -p ./coverage && forge coverage --no-match-coverage "script|test" --report lcov --report-file coverage/lcov.info && genhtml coverage/lcov.info -o coverage --branch-coverage
 snapshot        :; forge snapshot

foundry.toml

@@ -4,7 +4,7 @@ test = "test"
 out = "out"
 libs = ["lib"]
 remappings = []
-#ffi = true
+ffi = true
 ast = true
 build_info = true
 extra_output = ["storageLayout"]

remappings.txt

@@ -2,4 +2,5 @@ forge-std/=lib/forge-std/src/
 @openzeppelin/contracts/=lib/openzeppelin-contracts/contracts/
 @openzeppelin/contracts-upgradeable/=lib/openzeppelin-contracts-upgradeable/contracts/
 @chainlink/contracts/=lib/chainlink-brownie-contracts/contracts/src/
-@openzeppelin/community-contracts/=lib/openzeppelin-community-contracts/contracts/
+@openzeppelin/community-contracts/=lib/openzeppelin-community-contracts/contracts/
+@openzeppelin-foundry-upgrades/=lib/openzeppelin-foundry-upgrades/src/

script/DeployOracleMock.s.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: UNLICENSED
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 //import {Script, console} from "forge-std/Script.sol"; // not recognized by VS Code
 import {Script, console} from "lib/forge-std/src/Script.sol";

script/DeployToken.s.sol

@@ -1,12 +1,13 @@
 // SPDX-License-Identifier: UNLICENSED
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 //import {Script, console} from "forge-std/Script.sol"; // not recognized by VS Code
 import {Script, console} from "lib/forge-std/src/Script.sol";
 import {HelperConfig} from "./HelperConfig.s.sol";
 import {DeployOracleMock} from "./DeployOracleMock.s.sol";
 import {EmGEMxToken} from "../src/EmGEMxToken.sol";
 import {MockV3Aggregator} from "../test/mocks/MockV3Aggregator.sol";
+import {Upgrades} from "@openzeppelin-foundry-upgrades/Upgrades.sol";
 
 /**
  * @title Deployment script for the EmGEMx token contract
@@ -30,13 +31,16 @@ contract DeployToken is Script {
         }
         console.log("Oracle address:", esuOracle);
 
-        token = new EmGEMxToken();
-        console.log("Token address:", address(token));
-
         string memory tokenName = vm.envString("TOKEN_NAME"); // "EmGEMx Switzerland"
         string memory tokenSymbol = vm.envString("TOKEN_SYMBOL"); // "EmCH"
 
-        token.initialize(esuOracle, tokenName, tokenSymbol);
+        address proxyAddress = Upgrades.deployTransparentProxy(
+            "EmGEMxToken.sol", msg.sender, abi.encodeCall(EmGEMxToken.initialize, (esuOracle, tokenName, tokenSymbol))
+        );
+        token = EmGEMxToken(proxyAddress);
+        console.log("Token address:", address(token));
+        address implementationAddress = Upgrades.getImplementationAddress(proxyAddress);
+        console.log("Implementation address:", implementationAddress);
 
         vm.stopBroadcast();
 

script/GrantMinterRole.s.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: UNLICENSED
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 //import {Script, console} from "forge-std/Script.sol"; // not recognized by VS Code
 import {Script, console} from "lib/forge-std/src/Script.sol";

script/HelperConfig.s.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: UNLICENSED
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 import {MockV3Aggregator} from "../test/mocks/MockV3Aggregator.sol";
 import {Script, console} from "forge-std/Script.sol";

script/Mint.s.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: UNLICENSED
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 //import {Script, console} from "forge-std/Script.sol"; // not recognized by VS Code
 import {Script, console} from "lib/forge-std/src/Script.sol";

src/ERC20BlocklistUpgradeable.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: UNLICENSED
 
-pragma solidity ^0.8.20;
+pragma solidity 0.8.22;
 
 import {ERC20Upgradeable} from "@openzeppelin/contracts-upgradeable/token/ERC20/ERC20Upgradeable.sol";
 
@@ -17,10 +17,23 @@ import {ERC20Upgradeable} from "@openzeppelin/contracts-upgradeable/token/ERC20/
  * {_unblockUser} is called.
  */
 abstract contract ERC20BlocklistUpgradeable is ERC20Upgradeable {
-    /**
-     * @dev Blocked status of addresses. True if blocked, False otherwise.
-     */
-    mapping(address user => bool) private _blocked;
+    /// @custom:storage-location erc7201:ERC20BlocklistUpgradeable.storage
+    struct ERC20BlocklistUpgradeableStorage {
+        /**
+         * @dev Blocked status of addresses. True if blocked, False otherwise.
+         */
+        mapping(address user => bool) _blocked;
+    }
+
+    // keccak256(abi.encode(uint256(keccak256("ERC20BlocklistUpgradeable.storage")) - 1)) & ~bytes32(uint256(0xff))
+    bytes32 private constant ERC20BlocklistUpgradeableStorageLocation =
+        0x943d6f0aae33a11bdac5b1e1fa272eeefbfbb201792466fc6e6bfcdac78e2f00;
+
+    function _getERC20BlocklistStorage() private pure returns (ERC20BlocklistUpgradeableStorage storage $) {
+        assembly {
+            $.slot := ERC20BlocklistUpgradeableStorageLocation
+        }
+    }
 
     /**
      * @dev Emitted when a user is blocked.
@@ -40,8 +53,9 @@ abstract contract ERC20BlocklistUpgradeable is ERC20Upgradeable {
     /**
      * @dev Returns the blocked status of an account.
      */
-    function blocked(address account) public virtual returns (bool) {
-        return _blocked[account];
+    function blocked(address account) public view virtual returns (bool) {
+        ERC20BlocklistUpgradeableStorage storage $ = _getERC20BlocklistStorage();
+        return $._blocked[account];
     }
 
     /**
@@ -50,7 +64,8 @@ abstract contract ERC20BlocklistUpgradeable is ERC20Upgradeable {
     function _blockUser(address user) internal virtual returns (bool) {
         bool isBlocked = blocked(user);
         if (!isBlocked) {
-            _blocked[user] = true;
+            ERC20BlocklistUpgradeableStorage storage $ = _getERC20BlocklistStorage();
+            $._blocked[user] = true;
             emit UserBlocked(user);
         }
         return isBlocked;
@@ -62,7 +77,8 @@ abstract contract ERC20BlocklistUpgradeable is ERC20Upgradeable {
     function _unblockUser(address user) internal virtual returns (bool) {
         bool isBlocked = blocked(user);
         if (isBlocked) {
-            _blocked[user] = false;
+            ERC20BlocklistUpgradeableStorage storage $ = _getERC20BlocklistStorage();
+            $._blocked[user] = false;
             emit UserUnblocked(user);
         }
         return isBlocked;

src/ERC20FreezableUpgradeable.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: UNLICENSED
 
-pragma solidity ^0.8.20;
+pragma solidity 0.8.22;
 
 import {ERC20Upgradeable} from "@openzeppelin/contracts-upgradeable/token/ERC20/ERC20Upgradeable.sol";
 
@@ -20,10 +20,23 @@ import {ERC20Upgradeable} from "@openzeppelin/contracts-upgradeable/token/ERC20/
  * Taken from https://docs.openzeppelin.com/community-contracts/0.0.1/api/token#ERC20Custodian
  */
 abstract contract ERC20FreezableUpgradeable is ERC20Upgradeable {
-    /**
-     * @dev The amount of tokens frozen by user address.
-     */
-    mapping(address user => uint256 amount) private _frozen;
+    /// @custom:storage-location erc7201:ERC20FreezableUpgradeable.storage
+    struct ERC20FreezableUpgradeableStorage {
+        /**
+         * @dev The amount of tokens frozen by user address.
+         */
+        mapping(address user => uint256 amount) _frozen;
+    }
+
+    // keccak256(abi.encode(uint256(keccak256("ERC20FreezableUpgradeable.storage")) - 1)) & ~bytes32(uint256(0xff))
+    bytes32 private constant ERC20FreezableUpgradeableStorageLocation =
+        0x3fa3c15e60cd35140c36fb837aa364f49ac6961def966d04c318a640c7984100;
+
+    function _getERC20FreezableStorage() private pure returns (ERC20FreezableUpgradeableStorage storage $) {
+        assembly {
+            $.slot := ERC20FreezableUpgradeableStorageLocation
+        }
+    }
 
     /**
      * @dev Emitted when tokens are frozen for a user.
@@ -66,7 +79,8 @@ abstract contract ERC20FreezableUpgradeable is ERC20Upgradeable {
      * @dev Returns the amount of tokens frozen for a user.
      */
     function frozen(address user) public view virtual returns (uint256) {
-        return _frozen[user];
+        ERC20FreezableUpgradeableStorage storage $ = _getERC20FreezableStorage();
+        return $._frozen[user];
     }
 
     /**
@@ -80,7 +94,8 @@ abstract contract ERC20FreezableUpgradeable is ERC20Upgradeable {
      */
     function freeze(address user, uint256 amount) external virtual onlyFreezer {
         if (availableBalance(user) < amount) revert ERC20InsufficientUnfrozenBalance(user);
-        _frozen[user] = amount;
+        ERC20FreezableUpgradeableStorage storage $ = _getERC20FreezableStorage();
+        $._frozen[user] = amount;
         emit TokensFrozen(user, amount);
     }
 

src/EmGEMxToken.sol

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: UNLICENSED
 
-pragma solidity ^0.8.20;
+pragma solidity 0.8.22;
 
 import {AccessControlUpgradeable} from "@openzeppelin/contracts-upgradeable/access/AccessControlUpgradeable.sol";
 import {OwnableUpgradeable} from "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
@@ -70,9 +70,8 @@ contract EmGEMxToken is
     - max_tokens = esu / esu_per_token
     */
 
-    // initial esuPerToken: 0.01
-    uint256 private esuPerTokenValue = 1;
-    uint256 private esuPerTokenPrecision = 100;
+    uint256 private esuPerTokenValue;
+    uint256 private esuPerTokenPrecision;
 
     ///////////////////
     // Events
@@ -93,16 +92,24 @@ contract EmGEMxToken is
         _;
     }
 
+    /// @custom:oz-upgrades-unsafe-allow constructor
+    constructor() {
+        _disableInitializers();
+    }
+
     ///////////////////
     // Functions
     ///////////////////
 
-    function initialize(address oracleAddres, string memory name, string memory symbol) public initializer {
+    function initialize(address oracleAddress, string memory name, string memory symbol) public initializer {
+        validateNotZeroAddress(oracleAddress);
+
         __ERC20_init(name, symbol);
         __ERC20Burnable_init();
         __ERC20Pausable_init();
         __AccessControl_init();
         __Ownable_init(_msgSender());
+        __ERC20Permit_init(name);
         _grantRole(DEFAULT_ADMIN_ROLE, _msgSender());
         _setRoleAdmin(MINTER_ROLE, DEFAULT_ADMIN_ROLE);
         _setRoleAdmin(ESU_PER_TOKEN_MODIFIER_ROLE, DEFAULT_ADMIN_ROLE);
@@ -111,7 +118,11 @@ contract EmGEMxToken is
         _setRoleAdmin(LIMITER_ROLE, DEFAULT_ADMIN_ROLE);
         _setRoleAdmin(REDEEMER_ROLE, DEFAULT_ADMIN_ROLE);
 
-        oracle = AggregatorV3Interface(oracleAddres);
+        oracle = AggregatorV3Interface(oracleAddress);
+
+        // initial esuPerToken: 0.01
+        esuPerTokenValue = 1;
+        esuPerTokenPrecision = 100;
     }
 
     ///////////////////
@@ -124,8 +135,13 @@ contract EmGEMxToken is
     }
 
     /// @notice Wrapps ERC20BurnableUpgradeable._burn
-    function burn(address account, uint256 value) external onlyRole(MINTER_ROLE) {
-        _burn(account, value);
+    function burn(uint256 value) public override onlyRole(MINTER_ROLE) {
+        super.burn(value);
+    }
+
+    /// @notice Wrapps ERC20BurnableUpgradeable._burnFrom
+    function burnFrom(address account, uint256 value) public override onlyRole(MINTER_ROLE) {
+        super.burnFrom(account, value);
     }
 
     /// @notice Burns token from the redeemAddress.
@@ -215,6 +231,7 @@ contract EmGEMxToken is
             return type(uint256).max;
         }
 
+        // as returned oracle value has 8 decimals (same as token decimals) we can directly take it for token supply calculation
         return _getEsuFromOracle() * esuPerTokenPrecision / esuPerTokenValue;
     }
 
@@ -262,16 +279,19 @@ contract EmGEMxToken is
     /// @return The quried ESU value from the chainlink PoR oracle.
     function _getEsuFromOracle() private view returns (uint256) {
         (
-            /* uint80 roundID */
-            ,
+            uint80 roundID,
             int256 answer,
             /*uint startedAt*/
             ,
-            /*uint timeStamp*/
-            ,
-            /*uint80 answeredInRound*/
+            uint256 updatedAt,
+            uint80 answeredInRound
         ) = oracle.latestRoundData();
 
+        require(answer > 0, "PoR: answer is zero");
+        require(updatedAt > 0, "PoR: updatedAt is zero");
+        require(answeredInRound >= roundID, "PoR: data is stale");
+
+        // according to docs answer has always 8 decimals!
         return uint256(answer);
     }
 

test/mocks/MockV3Aggregator.sol

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: UNLICENSED
-pragma solidity 0.8.20;
+pragma solidity 0.8.22;
 
 import {AggregatorV3Interface} from "@chainlink/contracts/v0.8/shared/interfaces/AggregatorV3Interface.sol";
 
@@ -18,6 +18,7 @@ contract MockV3Aggregator is AggregatorV3Interface {
     int256 public latestAnswer;
     uint256 public latestTimestamp;
     uint256 public latestRound;
+    bool public isStale;
 
     mapping(uint256 => int256) public getAnswer;
     mapping(uint256 => uint256) public getTimestamp;
@@ -34,6 +35,7 @@ contract MockV3Aggregator is AggregatorV3Interface {
         getAnswer[latestRound] = _answer;
         getTimestamp[latestRound] = block.timestamp;
         getStartedAt[latestRound] = block.timestamp;
+        isStale = false;
     }
 
     function updateRoundData(uint80 _roundId, int256 _answer, uint256 _timestamp, uint256 _startedAt) public {
@@ -43,14 +45,15 @@ contract MockV3Aggregator is AggregatorV3Interface {
         getAnswer[latestRound] = _answer;
         getTimestamp[latestRound] = _timestamp;
         getStartedAt[latestRound] = _startedAt;
+        isStale = false;
     }
 
     function getRoundData(uint80 _roundId)
         external
         view
         returns (uint80 roundId, int256 answer, uint256 startedAt, uint256 updatedAt, uint80 answeredInRound)
     {
-        return (_roundId, getAnswer[_roundId], getStartedAt[_roundId], getTimestamp[_roundId], _roundId);
+        return (_roundId, getAnswer[_roundId], getStartedAt[_roundId], getTimestamp[_roundId], isStale ? 0 : _roundId);
     }
 
     function latestRoundData()
@@ -63,10 +66,14 @@ contract MockV3Aggregator is AggregatorV3Interface {
             getAnswer[latestRound],
             getStartedAt[latestRound],
             getTimestamp[latestRound],
-            uint80(latestRound)
+            isStale ? 0 : uint80(latestRound)
         );
     }
 
+    function setStale() external {
+        isStale = true;
+    }
+
     function description() external pure returns (string memory) {
         return "v0.6/tests/MockV3Aggregator.sol";
     }