// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }
    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }
    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "../../utils/Context.sol";
import "./IERC20.sol";
import "../../math/SafeMath.sol";
/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20 {
    using SafeMath for uint256;
    mapping (address => uint256) private _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    uint8 private _decimals;
    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    constructor (string memory name_, string memory symbol_) public {
        _name = name_;
        _symbol = symbol_;
        _decimals = 18;
    }
    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual returns (string memory) {
        return _name;
    }
    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual returns (string memory) {
        return _symbol;
    }
    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5,05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
     * called.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual returns (uint8) {
        return _decimals;
    }
    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }
    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }
    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }
    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }
    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }
    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * Requirements:
     *
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for ``sender``'s tokens of at least
     * `amount`.
     */
    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }
    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }
    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }
    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(address sender, address recipient, uint256 amount) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");
        _beforeTokenTransfer(sender, recipient, amount);
        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }
    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");
        _beforeTokenTransfer(address(0), account, amount);
        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }
    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");
        _beforeTokenTransfer(account, address(0), amount);
        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }
    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }
    /**
     * @dev Sets {decimals} to a value other than the default one of 18.
     *
     * WARNING: This function should only be called from the constructor. Most
     * applications that interact with token contracts will not expect
     * {decimals} to ever change, and may work incorrectly if it does.
     */
    function _setupDecimals(uint8 decimals_) internal virtual {
        _decimals = decimals_;
    }
    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be to transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}
/**
  *       .
  *      / \\
  *     |.'.|
  *     |'.'|
  *   ,'|   |`.
  *  |,-'-|-'-.|
  *   __|_| |         _        _      _____           _
  *  | ___ \\|        | |      | |    | ___ \\         | |
  *  | |_/ /|__   ___| | _____| |_   | |_/ /__   ___ | |
  *  |    // _ \\ / __| |/ / _ \\ __|  |  __/ _ \\ / _ \\| |
  *  | |\\ \\ (_) | (__|   <  __/ |_   | | | (_) | (_) | |
  *  \\_| \\_\\___/ \\___|_|\\_\\___|\\__|  \\_|  \\___/ \\___/|_|
  * +---------------------------------------------------+
  * |    DECENTRALISED STAKING PROTOCOL FOR ETHEREUM    |
  * +---------------------------------------------------+
  *
  *  Rocket Pool is a first-of-its-kind Ethereum staking pool protocol, designed to
  *  be community-owned, decentralised, and trustless.
  *
  *  For more information about Rocket Pool, visit https://rocketpool.net
  *
  *  Authors: David Rugendyke, Jake Pospischil, Kane Wallmann, Darren Langley, Joe Clapis, Nick Doherty
  *
  */
pragma solidity 0.7.6;
// SPDX-License-Identifier: GPL-3.0-only
import "../interface/RocketStorageInterface.sol";
/// @title Base settings / modifiers for each contract in Rocket Pool
/// @author David Rugendyke
abstract contract RocketBase {
    // Calculate using this as the base
    uint256 constant calcBase = 1 ether;
    // Version of the contract
    uint8 public version;
    // The main storage contract where primary persistant storage is maintained
    RocketStorageInterface rocketStorage = RocketStorageInterface(0);
    /*** Modifiers **********************************************************/
    /**
    * @dev Throws if called by any sender that doesn't match a Rocket Pool network contract
    */
    modifier onlyLatestNetworkContract() {
        require(getBool(keccak256(abi.encodePacked("contract.exists", msg.sender))), "Invalid or outdated network contract");
        _;
    }
    /**
    * @dev Throws if called by any sender that doesn't match one of the supplied contract or is the latest version of that contract
    */
    modifier onlyLatestContract(string memory _contractName, address _contractAddress) {
        require(_contractAddress == getAddress(keccak256(abi.encodePacked("contract.address", _contractName))), "Invalid or outdated contract");
        _;
    }
    /**
    * @dev Throws if called by any sender that isn't a registered node
    */
    modifier onlyRegisteredNode(address _nodeAddress) {
        require(getBool(keccak256(abi.encodePacked("node.exists", _nodeAddress))), "Invalid node");
        _;
    }
    /**
    * @dev Throws if called by any sender that isn't a trusted node DAO member
    */
    modifier onlyTrustedNode(address _nodeAddress) {
        require(getBool(keccak256(abi.encodePacked("dao.trustednodes.", "member", _nodeAddress))), "Invalid trusted node");
        _;
    }
    /**
    * @dev Throws if called by any sender that isn't a registered minipool
    */
    modifier onlyRegisteredMinipool(address _minipoolAddress) {
        require(getBool(keccak256(abi.encodePacked("minipool.exists", _minipoolAddress))), "Invalid minipool");
        _;
    }
    
    /**
    * @dev Throws if called by any account other than a guardian account (temporary account allowed access to settings before DAO is fully enabled)
    */
    modifier onlyGuardian() {
        require(msg.sender == rocketStorage.getGuardian(), "Account is not a temporary guardian");
        _;
    }
    /*** Methods **********************************************************/
    /// @dev Set the main Rocket Storage address
    constructor(RocketStorageInterface _rocketStorageAddress) {
        // Update the contract address
        rocketStorage = RocketStorageInterface(_rocketStorageAddress);
    }
    /// @dev Get the address of a network contract by name
    function getContractAddress(string memory _contractName) internal view returns (address) {
        // Get the current contract address
        address contractAddress = getAddress(keccak256(abi.encodePacked("contract.address", _contractName)));
        // Check it
        require(contractAddress != address(0x0), "Contract not found");
        // Return
        return contractAddress;
    }
    /// @dev Get the address of a network contract by name (returns address(0x0) instead of reverting if contract does not exist)
    function getContractAddressUnsafe(string memory _contractName) internal view returns (address) {
        // Get the current contract address
        address contractAddress = getAddress(keccak256(abi.encodePacked("contract.address", _contractName)));
        // Return
        return contractAddress;
    }
    /// @dev Get the name of a network contract by address
    function getContractName(address _contractAddress) internal view returns (string memory) {
        // Get the contract name
        string memory contractName = getString(keccak256(abi.encodePacked("contract.name", _contractAddress)));
        // Check it
        require(bytes(contractName).length > 0, "Contract not found");
        // Return
        return contractName;
    }
    /// @dev Get revert error message from a .call method
    function getRevertMsg(bytes memory _returnData) internal pure returns (string memory) {
        // If the _res length is less than 68, then the transaction failed silently (without a revert message)
        if (_returnData.length < 68) return "Transaction reverted silently";
        assembly {
            // Slice the sighash.
            _returnData := add(_returnData, 0x04)
        }
        return abi.decode(_returnData, (string)); // All that remains is the revert string
    }
    /*** Rocket Storage Methods ****************************************/
    // Note: Unused helpers have been removed to keep contract sizes down
    /// @dev Storage get methods
    function getAddress(bytes32 _key) internal view returns (address) { return rocketStorage.getAddress(_key); }
    function getUint(bytes32 _key) internal view returns (uint) { return rocketStorage.getUint(_key); }
    function getString(bytes32 _key) internal view returns (string memory) { return rocketStorage.getString(_key); }
    function getBytes(bytes32 _key) internal view returns (bytes memory) { return rocketStorage.getBytes(_key); }
    function getBool(bytes32 _key) internal view returns (bool) { return rocketStorage.getBool(_key); }
    function getInt(bytes32 _key) internal view returns (int) { return rocketStorage.getInt(_key); }
    function getBytes32(bytes32 _key) internal view returns (bytes32) { return rocketStorage.getBytes32(_key); }
    /// @dev Storage set methods
    function setAddress(bytes32 _key, address _value) internal { rocketStorage.setAddress(_key, _value); }
    function setUint(bytes32 _key, uint _value) internal { rocketStorage.setUint(_key, _value); }
    function setString(bytes32 _key, string memory _value) internal { rocketStorage.setString(_key, _value); }
    function setBytes(bytes32 _key, bytes memory _value) internal { rocketStorage.setBytes(_key, _value); }
    function setBool(bytes32 _key, bool _value) internal { rocketStorage.setBool(_key, _value); }
    function setInt(bytes32 _key, int _value) internal { rocketStorage.setInt(_key, _value); }
    function setBytes32(bytes32 _key, bytes32 _value) internal { rocketStorage.setBytes32(_key, _value); }
    /// @dev Storage delete methods
    function deleteAddress(bytes32 _key) internal { rocketStorage.deleteAddress(_key); }
    function deleteUint(bytes32 _key) internal { rocketStorage.deleteUint(_key); }
    function deleteString(bytes32 _key) internal { rocketStorage.deleteString(_key); }
    function deleteBytes(bytes32 _key) internal { rocketStorage.deleteBytes(_key); }
    function deleteBool(bytes32 _key) internal { rocketStorage.deleteBool(_key); }
    function deleteInt(bytes32 _key) internal { rocketStorage.deleteInt(_key); }
    function deleteBytes32(bytes32 _key) internal { rocketStorage.deleteBytes32(_key); }
    /// @dev Storage arithmetic methods
    function addUint(bytes32 _key, uint256 _amount) internal { rocketStorage.addUint(_key, _amount); }
    function subUint(bytes32 _key, uint256 _amount) internal { rocketStorage.subUint(_key, _amount); }
}
/**
  *       .
  *      / \\
  *     |.'.|
  *     |'.'|
  *   ,'|   |`.
  *  |,-'-|-'-.|
  *   __|_| |         _        _      _____           _
  *  | ___ \\|        | |      | |    | ___ \\         | |
  *  | |_/ /|__   ___| | _____| |_   | |_/ /__   ___ | |
  *  |    // _ \\ / __| |/ / _ \\ __|  |  __/ _ \\ / _ \\| |
  *  | |\\ \\ (_) | (__|   <  __/ |_   | | | (_) | (_) | |
  *  \\_| \\_\\___/ \\___|_|\\_\\___|\\__|  \\_|  \\___/ \\___/|_|
  * +---------------------------------------------------+
  * |    DECENTRALISED STAKING PROTOCOL FOR ETHEREUM    |
  * +---------------------------------------------------+
  *
  *  Rocket Pool is a first-of-its-kind Ethereum staking pool protocol, designed to
  *  be community-owned, decentralised, and trustless.
  *
  *  For more information about Rocket Pool, visit https://rocketpool.net
  *
  *  Authors: David Rugendyke, Jake Pospischil, Kane Wallmann, Darren Langley, Joe Clapis, Nick Doherty
  *
  */
pragma solidity 0.7.6;
// SPDX-License-Identifier: GPL-3.0-only
import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "../RocketBase.sol";
import "../../interface/deposit/RocketDepositPoolInterface.sol";
import "../../interface/network/RocketNetworkBalancesInterface.sol";
import "../../interface/token/RocketTokenRETHInterface.sol";
import "../../interface/dao/protocol/settings/RocketDAOProtocolSettingsNetworkInterface.sol";
// rETH is a tokenised stake in the Rocket Pool network
// rETH is backed by ETH (subject to liquidity) at a variable exchange rate
contract RocketTokenRETH is RocketBase, ERC20, RocketTokenRETHInterface {
    // Libs
    using SafeMath for uint;
    // Events
    event EtherDeposited(address indexed from, uint256 amount, uint256 time);
    event TokensMinted(address indexed to, uint256 amount, uint256 ethAmount, uint256 time);
    event TokensBurned(address indexed from, uint256 amount, uint256 ethAmount, uint256 time);
    // Construct with our token details
    constructor(RocketStorageInterface _rocketStorageAddress) RocketBase(_rocketStorageAddress) ERC20("Rocket Pool ETH", "rETH") {
        // Version
        version = 1;
    }
    // Receive an ETH deposit from a minipool or generous individual
    receive() external payable {
        // Emit ether deposited event
        emit EtherDeposited(msg.sender, msg.value, block.timestamp);
    }
    // Calculate the amount of ETH backing an amount of rETH
    function getEthValue(uint256 _rethAmount) override public view returns (uint256) {
        // Get network balances
        RocketNetworkBalancesInterface rocketNetworkBalances = RocketNetworkBalancesInterface(getContractAddress("rocketNetworkBalances"));
        uint256 totalEthBalance = rocketNetworkBalances.getTotalETHBalance();
        uint256 rethSupply = rocketNetworkBalances.getTotalRETHSupply();
        // Use 1:1 ratio if no rETH is minted
        if (rethSupply == 0) { return _rethAmount; }
        // Calculate and return
        return _rethAmount.mul(totalEthBalance).div(rethSupply);
    }
    // Calculate the amount of rETH backed by an amount of ETH
    function getRethValue(uint256 _ethAmount) override public view returns (uint256) {
        // Get network balances
        RocketNetworkBalancesInterface rocketNetworkBalances = RocketNetworkBalancesInterface(getContractAddress("rocketNetworkBalances"));
        uint256 totalEthBalance = rocketNetworkBalances.getTotalETHBalance();
        uint256 rethSupply = rocketNetworkBalances.getTotalRETHSupply();
        // Use 1:1 ratio if no rETH is minted
        if (rethSupply == 0) { return _ethAmount; }
        // Check network ETH balance
        require(totalEthBalance > 0, "Cannot calculate rETH token amount while total network balance is zero");
        // Calculate and return
        return _ethAmount.mul(rethSupply).div(totalEthBalance);
    }
    // Get the current ETH : rETH exchange rate
    // Returns the amount of ETH backing 1 rETH
    function getExchangeRate() override external view returns (uint256) {
        return getEthValue(1 ether);
    }
    // Get the total amount of collateral available
    // Includes rETH contract balance & excess deposit pool balance
    function getTotalCollateral() override public view returns (uint256) {
        RocketDepositPoolInterface rocketDepositPool = RocketDepositPoolInterface(getContractAddress("rocketDepositPool"));
        return rocketDepositPool.getExcessBalance().add(address(this).balance);
    }
    // Get the current ETH collateral rate
    // Returns the portion of rETH backed by ETH in the contract as a fraction of 1 ether
    function getCollateralRate() override public view returns (uint256) {
        uint256 totalEthValue = getEthValue(totalSupply());
        if (totalEthValue == 0) { return calcBase; }
        return calcBase.mul(address(this).balance).div(totalEthValue);
    }
    // Deposit excess ETH from deposit pool
    // Only accepts calls from the RocketDepositPool contract
    function depositExcess() override external payable onlyLatestContract("rocketDepositPool", msg.sender) {
        // Emit ether deposited event
        emit EtherDeposited(msg.sender, msg.value, block.timestamp);
    }
    // Mint rETH
    // Only accepts calls from the RocketDepositPool contract
    function mint(uint256 _ethAmount, address _to) override external onlyLatestContract("rocketDepositPool", msg.sender) {
        // Get rETH amount
        uint256 rethAmount = getRethValue(_ethAmount);
        // Check rETH amount
        require(rethAmount > 0, "Invalid token mint amount");
        // Update balance & supply
        _mint(_to, rethAmount);
        // Emit tokens minted event
        emit TokensMinted(_to, rethAmount, _ethAmount, block.timestamp);
    }
    // Burn rETH for ETH
    function burn(uint256 _rethAmount) override external {
        // Check rETH amount
        require(_rethAmount > 0, "Invalid token burn amount");
        require(balanceOf(msg.sender) >= _rethAmount, "Insufficient rETH balance");
        // Get ETH amount
        uint256 ethAmount = getEthValue(_rethAmount);
        // Get & check ETH balance
        uint256 ethBalance = getTotalCollateral();
        require(ethBalance >= ethAmount, "Insufficient ETH balance for exchange");
        // Update balance & supply
        _burn(msg.sender, _rethAmount);
        // Withdraw ETH from deposit pool if required
        withdrawDepositCollateral(ethAmount);
        // Transfer ETH to sender
        msg.sender.transfer(ethAmount);
        // Emit tokens burned event
        emit TokensBurned(msg.sender, _rethAmount, ethAmount, block.timestamp);
    }
    // Withdraw ETH from the deposit pool for collateral if required
    function withdrawDepositCollateral(uint256 _ethRequired) private {
        // Check rETH contract balance
        uint256 ethBalance = address(this).balance;
        if (ethBalance >= _ethRequired) { return; }
        // Withdraw
        RocketDepositPoolInterface rocketDepositPool = RocketDepositPoolInterface(getContractAddress("rocketDepositPool"));
        rocketDepositPool.withdrawExcessBalance(_ethRequired.sub(ethBalance));
    }
    // Sends any excess ETH from this contract to the deposit pool (as determined by target collateral rate)
    function depositExcessCollateral() external override {
        // Load contracts
        RocketDAOProtocolSettingsNetworkInterface rocketDAOProtocolSettingsNetwork = RocketDAOProtocolSettingsNetworkInterface(getContractAddress("rocketDAOProtocolSettingsNetwork"));
        RocketDepositPoolInterface rocketDepositPool = RocketDepositPoolInterface(getContractAddress("rocketDepositPool"));
        // Get collateral and target collateral rate
        uint256 collateralRate = getCollateralRate();
        uint256 targetCollateralRate = rocketDAOProtocolSettingsNetwork.getTargetRethCollateralRate();
        // Check if we are in excess
        if (collateralRate > targetCollateralRate) {
            // Calculate our target collateral in ETH
            uint256 targetCollateral = address(this).balance.mul(targetCollateralRate).div(collateralRate);
            // If we have excess
            if (address(this).balance > targetCollateral) {
                // Send that excess to deposit pool
                uint256 excessCollateral = address(this).balance.sub(targetCollateral);
                rocketDepositPool.recycleExcessCollateral{value: excessCollateral}();
            }
        }
    }
    // This is called by the base ERC20 contract before all transfer, mint, and burns
    function _beforeTokenTransfer(address from, address, uint256) internal override {
        // Don't run check if this is a mint transaction
        if (from != address(0)) {
            // Check which block the user's last deposit was
            bytes32 key = keccak256(abi.encodePacked("user.deposit.block", from));
            uint256 lastDepositBlock = getUint(key);
            if (lastDepositBlock > 0) {
                // Ensure enough blocks have passed
                uint256 depositDelay = getUint(keccak256(abi.encodePacked(keccak256("dao.protocol.setting.network"), "network.reth.deposit.delay")));
                uint256 blocksPassed = block.number.sub(lastDepositBlock);
                require(blocksPassed > depositDelay, "Not enough time has passed since deposit");
                // Clear the state as it's no longer necessary to check this until another deposit is made
                deleteUint(key);
            }
        }
    }
}
/**
  *       .
  *      / \\
  *     |.'.|
  *     |'.'|
  *   ,'|   |`.
  *  |,-'-|-'-.|
  *   __|_| |         _        _      _____           _
  *  | ___ \\|        | |      | |    | ___ \\         | |
  *  | |_/ /|__   ___| | _____| |_   | |_/ /__   ___ | |
  *  |    // _ \\ / __| |/ / _ \\ __|  |  __/ _ \\ / _ \\| |
  *  | |\\ \\ (_) | (__|   <  __/ |_   | | | (_) | (_) | |
  *  \\_| \\_\\___/ \\___|_|\\_\\___|\\__|  \\_|  \\___/ \\___/|_|
  * +---------------------------------------------------+
  * |    DECENTRALISED STAKING PROTOCOL FOR ETHEREUM    |
  * +---------------------------------------------------+
  *
  *  Rocket Pool is a first-of-its-kind Ethereum staking pool protocol, designed to
  *  be community-owned, decentralised, and trustless.
  *
  *  For more information about Rocket Pool, visit https://rocketpool.net
  *
  *  Authors: David Rugendyke, Jake Pospischil, Kane Wallmann, Darren Langley, Joe Clapis, Nick Doherty
  *
  */
pragma solidity 0.7.6;
// SPDX-License-Identifier: GPL-3.0-only
interface RocketStorageInterface {
    // Deploy status
    function getDeployedStatus() external view returns (bool);
    // Guardian
    function getGuardian() external view returns(address);
    function setGuardian(address _newAddress) external;
    function confirmGuardian() external;
    // Getters
    function getAddress(bytes32 _key) external view returns (address);
    function getUint(bytes32 _key) external view returns (uint);
    function getString(bytes32 _key) external view returns (string memory);
    function getBytes(bytes32 _key) external view returns (bytes memory);
    function getBool(bytes32 _key) external view returns (bool);
    function getInt(bytes32 _key) external view returns (int);
    function getBytes32(bytes32 _key) external view returns (bytes32);
    // Setters
    function setAddress(bytes32 _key, address _value) external;
    function setUint(bytes32 _key, uint _value) external;
    function setString(bytes32 _key, string calldata _value) external;
    function setBytes(bytes32 _key, bytes calldata _value) external;
    function setBool(bytes32 _key, bool _value) external;
    function setInt(bytes32 _key, int _value) external;
    function setBytes32(bytes32 _key, bytes32 _value) external;
    // Deleters
    function deleteAddress(bytes32 _key) external;
    function deleteUint(bytes32 _key) external;
    function deleteString(bytes32 _key) external;
    function deleteBytes(bytes32 _key) external;
    function deleteBool(bytes32 _key) external;
    function deleteInt(bytes32 _key) external;
    function deleteBytes32(bytes32 _key) external;
    // Arithmetic
    function addUint(bytes32 _key, uint256 _amount) external;
    function subUint(bytes32 _key, uint256 _amount) external;
    // Protected storage
    function getNodeWithdrawalAddress(address _nodeAddress) external view returns (address);
    function getNodePendingWithdrawalAddress(address _nodeAddress) external view returns (address);
    function setWithdrawalAddress(address _nodeAddress, address _newWithdrawalAddress, bool _confirm) external;
    function confirmWithdrawalAddress(address _nodeAddress) external;
}
/**
  *       .
  *      / \\
  *     |.'.|
  *     |'.'|
  *   ,'|   |`.
  *  |,-'-|-'-.|
  *   __|_| |         _        _      _____           _
  *  | ___ \\|        | |      | |    | ___ \\         | |
  *  | |_/ /|__   ___| | _____| |_   | |_/ /__   ___ | |
  *  |    // _ \\ / __| |/ / _ \\ __|  |  __/ _ \\ / _ \\| |
  *  | |\\ \\ (_) | (__|   <  __/ |_   | | | (_) | (_) | |
  *  \\_| \\_\\___/ \\___|_|\\_\\___|\\__|  \\_|  \\___/ \\___/|_|
  * +---------------------------------------------------+
  * |    DECENTRALISED STAKING PROTOCOL FOR ETHEREUM    |
  * +---------------------------------------------------+
  *
  *  Rocket Pool is a first-of-its-kind Ethereum staking pool protocol, designed to
  *  be community-owned, decentralised, and trustless.
  *
  *  For more information about Rocket Pool, visit https://rocketpool.net
  *
  *  Authors: David Rugendyke, Jake Pospischil, Kane Wallmann, Darren Langley, Joe Clapis, Nick Doherty
  *
  */
pragma solidity 0.7.6;
// SPDX-License-Identifier: GPL-3.0-only
interface RocketDAOProtocolSettingsNetworkInterface {
    function getNodeConsensusThreshold() external view returns (uint256);
    function getSubmitBalancesEnabled() external view returns (bool);
    function getSubmitBalancesFrequency() external view returns (uint256);
    function getSubmitPricesEnabled() external view returns (bool);
    function getSubmitPricesFrequency() external view returns (uint256);
    function getMinimumNodeFee() external view returns (uint256);
    function getTargetNodeFee() external view returns (uint256);
    function getMaximumNodeFee() external view returns (uint256);
    function getNodeFeeDemandRange() external view returns (uint256);
    function getTargetRethCollateralRate() external view returns (uint256);
    function getRethDepositDelay() external view returns (uint256);
}
/**
  *       .
  *      / \\
  *     |.'.|
  *     |'.'|
  *   ,'|   |`.
  *  |,-'-|-'-.|
  *   __|_| |         _        _      _____           _
  *  | ___ \\|        | |      | |    | ___ \\         | |
  *  | |_/ /|__   ___| | _____| |_   | |_/ /__   ___ | |
  *  |    // _ \\ / __| |/ / _ \\ __|  |  __/ _ \\ / _ \\| |
  *  | |\\ \\ (_) | (__|   <  __/ |_   | | | (_) | (_) | |
  *  \\_| \\_\\___/ \\___|_|\\_\\___|\\__|  \\_|  \\___/ \\___/|_|
  * +---------------------------------------------------+
  * |    DECENTRALISED STAKING PROTOCOL FOR ETHEREUM    |
  * +---------------------------------------------------+
  *
  *  Rocket Pool is a first-of-its-kind Ethereum staking pool protocol, designed to
  *  be community-owned, decentralised, and trustless.
  *
  *  For more information about Rocket Pool, visit https://rocketpool.net
  *
  *  Authors: David Rugendyke, Jake Pospischil, Kane Wallmann, Darren Langley, Joe Clapis, Nick Doherty
  *
  */
pragma solidity 0.7.6;
// SPDX-License-Identifier: GPL-3.0-only
interface RocketDepositPoolInterface {
    function getBalance() external view returns (uint256);
    function getExcessBalance() external view returns (uint256);
    function deposit() external payable;
    function recycleDissolvedDeposit() external payable;
    function recycleExcessCollateral() external payable;
    function recycleLiquidatedStake() external payable;
    function assignDeposits() external;
    function withdrawExcessBalance(uint256 _amount) external;
    function getUserLastDepositBlock(address _address) external view returns (uint256);
}
/**
  *       .
  *      / \\
  *     |.'.|
  *     |'.'|
  *   ,'|   |`.
  *  |,-'-|-'-.|
  *   __|_| |         _        _      _____           _
  *  | ___ \\|        | |      | |    | ___ \\         | |
  *  | |_/ /|__   ___| | _____| |_   | |_/ /__   ___ | |
  *  |    // _ \\ / __| |/ / _ \\ __|  |  __/ _ \\ / _ \\| |
  *  | |\\ \\ (_) | (__|   <  __/ |_   | | | (_) | (_) | |
  *  \\_| \\_\\___/ \\___|_|\\_\\___|\\__|  \\_|  \\___/ \\___/|_|
  * +---------------------------------------------------+
  * |    DECENTRALISED STAKING PROTOCOL FOR ETHEREUM    |
  * +---------------------------------------------------+
  *
  *  Rocket Pool is a first-of-its-kind Ethereum staking pool protocol, designed to
  *  be community-owned, decentralised, and trustless.
  *
  *  For more information about Rocket Pool, visit https://rocketpool.net
  *
  *  Authors: David Rugendyke, Jake Pospischil, Kane Wallmann, Darren Langley, Joe Clapis, Nick Doherty
  *
  */
pragma solidity 0.7.6;
// SPDX-License-Identifier: GPL-3.0-only
interface RocketNetworkBalancesInterface {
    function getBalancesBlock() external view returns (uint256);
    function getLatestReportableBlock() external view returns (uint256);
    function getTotalETHBalance() external view returns (uint256);
    function getStakingETHBalance() external view returns (uint256);
    function getTotalRETHSupply() external view returns (uint256);
    function getETHUtilizationRate() external view returns (uint256);
    function submitBalances(uint256 _block, uint256 _total, uint256 _staking, uint256 _rethSupply) external;
    function executeUpdateBalances(uint256 _block, uint256 _totalEth, uint256 _stakingEth, uint256 _rethSupply) external;
}
/**
  *       .
  *      / \\
  *     |.'.|
  *     |'.'|
  *   ,'|   |`.
  *  |,-'-|-'-.|
  *   __|_| |         _        _      _____           _
  *  | ___ \\|        | |      | |    | ___ \\         | |
  *  | |_/ /|__   ___| | _____| |_   | |_/ /__   ___ | |
  *  |    // _ \\ / __| |/ / _ \\ __|  |  __/ _ \\ / _ \\| |
  *  | |\\ \\ (_) | (__|   <  __/ |_   | | | (_) | (_) | |
  *  \\_| \\_\\___/ \\___|_|\\_\\___|\\__|  \\_|  \\___/ \\___/|_|
  * +---------------------------------------------------+
  * |    DECENTRALISED STAKING PROTOCOL FOR ETHEREUM    |
  * +---------------------------------------------------+
  *
  *  Rocket Pool is a first-of-its-kind Ethereum staking pool protocol, designed to
  *  be community-owned, decentralised, and trustless.
  *
  *  For more information about Rocket Pool, visit https://rocketpool.net
  *
  *  Authors: David Rugendyke, Jake Pospischil, Kane Wallmann, Darren Langley, Joe Clapis, Nick Doherty
  *
  */
pragma solidity 0.7.6;
// SPDX-License-Identifier: GPL-3.0-only
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
interface RocketTokenRETHInterface is IERC20 {
    function getEthValue(uint256 _rethAmount) external view returns (uint256);
    function getRethValue(uint256 _ethAmount) external view returns (uint256);
    function getExchangeRate() external view returns (uint256);
    function getTotalCollateral() external view returns (uint256);
    function getCollateralRate() external view returns (uint256);
    function depositExcess() external payable;
    function depositExcessCollateral() external;
    function mint(uint256 _ethAmount, address _to) external;
    function burn(uint256 _rethAmount) external;
}

// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }
    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }
    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}
/**
  *       .
  *      / \\
  *     |.'.|
  *     |'.'|
  *   ,'|   |`.
  *  |,-'-|-'-.|
  *   __|_| |         _        _      _____           _
  *  | ___ \\|        | |      | |    | ___ \\         | |
  *  | |_/ /|__   ___| | _____| |_   | |_/ /__   ___ | |
  *  |    // _ \\ / __| |/ / _ \\ __|  |  __/ _ \\ / _ \\| |
  *  | |\\ \\ (_) | (__|   <  __/ |_   | | | (_) | (_) | |
  *  \\_| \\_\\___/ \\___|_|\\_\\___|\\__|  \\_|  \\___/ \\___/|_|
  * +---------------------------------------------------+
  * |    DECENTRALISED STAKING PROTOCOL FOR ETHEREUM    |
  * +---------------------------------------------------+
  *
  *  Rocket Pool is a first-of-its-kind Ethereum staking pool protocol, designed to
  *  be community-owned, decentralised, and trustless.
  *
  *  For more information about Rocket Pool, visit https://rocketpool.net
  *
  *  Authors: David Rugendyke, Jake Pospischil, Kane Wallmann, Darren Langley, Joe Clapis, Nick Doherty
  *
  */
pragma solidity 0.7.6;
// SPDX-License-Identifier: GPL-3.0-only
import "../interface/RocketStorageInterface.sol";
import "@openzeppelin/contracts/math/SafeMath.sol";
/// @title The primary persistent storage for Rocket Pool
/// @author David Rugendyke
contract RocketStorage is RocketStorageInterface {
    // Events
    event NodeWithdrawalAddressSet(address indexed node, address indexed withdrawalAddress, uint256 time);
    event GuardianChanged(address oldGuardian, address newGuardian);
    // Libraries
    using SafeMath for uint256;
    // Storage maps
    mapping(bytes32 => string)     private stringStorage;
    mapping(bytes32 => bytes)      private bytesStorage;
    mapping(bytes32 => uint256)    private uintStorage;
    mapping(bytes32 => int256)     private intStorage;
    mapping(bytes32 => address)    private addressStorage;
    mapping(bytes32 => bool)       private booleanStorage;
    mapping(bytes32 => bytes32)    private bytes32Storage;
    // Protected storage (not accessible by network contracts)
    mapping(address => address)    private withdrawalAddresses;
    mapping(address => address)    private pendingWithdrawalAddresses;
    // Guardian address
    address guardian;
    address newGuardian;
    // Flag storage has been initialised
    bool storageInit = false;
    /// @dev Only allow access from the latest version of a contract in the Rocket Pool network after deployment
    modifier onlyLatestRocketNetworkContract() {
        if (storageInit == true) {
            // Make sure the access is permitted to only contracts in our Dapp
            require(booleanStorage[keccak256(abi.encodePacked("contract.exists", msg.sender))], "Invalid or outdated network contract");
        } else {
            // Only Dapp and the guardian account are allowed access during initialisation.
            // tx.origin is only safe to use in this case for deployment since no external contracts are interacted with
            require((
                booleanStorage[keccak256(abi.encodePacked("contract.exists", msg.sender))] || tx.origin == guardian
            ), "Invalid or outdated network contract attempting access during deployment");
        }
        _;
    }
    /// @dev Construct RocketStorage
    constructor() {
        // Set the guardian upon deployment
        guardian = msg.sender;
    }
    // Get guardian address
    function getGuardian() external override view returns (address) {
        return guardian;
    }
    // Transfers guardianship to a new address
    function setGuardian(address _newAddress) external override {
        // Check tx comes from current guardian
        require(msg.sender == guardian, "Is not guardian account");
        // Store new address awaiting confirmation
        newGuardian = _newAddress;
    }
    // Confirms change of guardian
    function confirmGuardian() external override {
        // Check tx came from new guardian address
        require(msg.sender == newGuardian, "Confirmation must come from new guardian address");
        // Store old guardian for event
        address oldGuardian = guardian;
        // Update guardian and clear storage
        guardian = newGuardian;
        delete newGuardian;
        // Emit event
        emit GuardianChanged(oldGuardian, guardian);
    }
    // Set this as being deployed now
    function getDeployedStatus() external override view returns (bool) {
        return storageInit;
    }
    // Set this as being deployed now
    function setDeployedStatus() external {
        // Only guardian can lock this down
        require(msg.sender == guardian, "Is not guardian account");
        // Set it now
        storageInit = true;
    }
    // Protected storage
    // Get a node's withdrawal address
    function getNodeWithdrawalAddress(address _nodeAddress) public override view returns (address) {
        // If no withdrawal address has been set, return the nodes address
        address withdrawalAddress = withdrawalAddresses[_nodeAddress];
        if (withdrawalAddress == address(0)) {
            return _nodeAddress;
        }
        return withdrawalAddress;
    }
    // Get a node's pending withdrawal address
    function getNodePendingWithdrawalAddress(address _nodeAddress) external override view returns (address) {
        return pendingWithdrawalAddresses[_nodeAddress];
    }
    // Set a node's withdrawal address
    function setWithdrawalAddress(address _nodeAddress, address _newWithdrawalAddress, bool _confirm) external override {
        // Check new withdrawal address
        require(_newWithdrawalAddress != address(0x0), "Invalid withdrawal address");
        // Confirm the transaction is from the node's current withdrawal address
        address withdrawalAddress = getNodeWithdrawalAddress(_nodeAddress);
        require(withdrawalAddress == msg.sender, "Only a tx from a node's withdrawal address can update it");
        // Update immediately if confirmed
        if (_confirm) {
            updateWithdrawalAddress(_nodeAddress, _newWithdrawalAddress);
        }
        // Set pending withdrawal address if not confirmed
        else {
            pendingWithdrawalAddresses[_nodeAddress] = _newWithdrawalAddress;
        }
    }
    // Confirm a node's new withdrawal address
    function confirmWithdrawalAddress(address _nodeAddress) external override {
        // Get node by pending withdrawal address
        require(pendingWithdrawalAddresses[_nodeAddress] == msg.sender, "Confirmation must come from the pending withdrawal address");
        delete pendingWithdrawalAddresses[_nodeAddress];
        // Update withdrawal address
        updateWithdrawalAddress(_nodeAddress, msg.sender);
    }
    // Update a node's withdrawal address
    function updateWithdrawalAddress(address _nodeAddress, address _newWithdrawalAddress) private {
        // Set new withdrawal address
        withdrawalAddresses[_nodeAddress] = _newWithdrawalAddress;
        // Emit withdrawal address set event
        emit NodeWithdrawalAddressSet(_nodeAddress, _newWithdrawalAddress, block.timestamp);
    }
    /// @param _key The key for the record
    function getAddress(bytes32 _key) override external view returns (address r) {
        return addressStorage[_key];
    }
    /// @param _key The key for the record
    function getUint(bytes32 _key) override external view returns (uint256 r) {
        return uintStorage[_key];
    }
    /// @param _key The key for the record
    function getString(bytes32 _key) override external view returns (string memory) {
        return stringStorage[_key];
    }
    /// @param _key The key for the record
    function getBytes(bytes32 _key) override external view returns (bytes memory) {
        return bytesStorage[_key];
    }
    /// @param _key The key for the record
    function getBool(bytes32 _key) override external view returns (bool r) {
        return booleanStorage[_key];
    }
    /// @param _key The key for the record
    function getInt(bytes32 _key) override external view returns (int r) {
        return intStorage[_key];
    }
    /// @param _key The key for the record
    function getBytes32(bytes32 _key) override external view returns (bytes32 r) {
        return bytes32Storage[_key];
    }
    /// @param _key The key for the record
    function setAddress(bytes32 _key, address _value) onlyLatestRocketNetworkContract override external {
        addressStorage[_key] = _value;
    }
    /// @param _key The key for the record
    function setUint(bytes32 _key, uint _value) onlyLatestRocketNetworkContract override external {
        uintStorage[_key] = _value;
    }
    /// @param _key The key for the record
    function setString(bytes32 _key, string calldata _value) onlyLatestRocketNetworkContract override external {
        stringStorage[_key] = _value;
    }
    /// @param _key The key for the record
    function setBytes(bytes32 _key, bytes calldata _value) onlyLatestRocketNetworkContract override external {
        bytesStorage[_key] = _value;
    }
    /// @param _key The key for the record
    function setBool(bytes32 _key, bool _value) onlyLatestRocketNetworkContract override external {
        booleanStorage[_key] = _value;
    }
    /// @param _key The key for the record
    function setInt(bytes32 _key, int _value) onlyLatestRocketNetworkContract override external {
        intStorage[_key] = _value;
    }
    /// @param _key The key for the record
    function setBytes32(bytes32 _key, bytes32 _value) onlyLatestRocketNetworkContract override external {
        bytes32Storage[_key] = _value;
    }
    /// @param _key The key for the record
    function deleteAddress(bytes32 _key) onlyLatestRocketNetworkContract override external {
        delete addressStorage[_key];
    }
    /// @param _key The key for the record
    function deleteUint(bytes32 _key) onlyLatestRocketNetworkContract override external {
        delete uintStorage[_key];
    }
    /// @param _key The key for the record
    function deleteString(bytes32 _key) onlyLatestRocketNetworkContract override external {
        delete stringStorage[_key];
    }
    /// @param _key The key for the record
    function deleteBytes(bytes32 _key) onlyLatestRocketNetworkContract override external {
        delete bytesStorage[_key];
    }
    /// @param _key The key for the record
    function deleteBool(bytes32 _key) onlyLatestRocketNetworkContract override external {
        delete booleanStorage[_key];
    }
    /// @param _key The key for the record
    function deleteInt(bytes32 _key) onlyLatestRocketNetworkContract override external {
        delete intStorage[_key];
    }
    /// @param _key The key for the record
    function deleteBytes32(bytes32 _key) onlyLatestRocketNetworkContract override external {
        delete bytes32Storage[_key];
    }
    /// @param _key The key for the record
    /// @param _amount An amount to add to the record's value
    function addUint(bytes32 _key, uint256 _amount) onlyLatestRocketNetworkContract override external {
        uintStorage[_key] = uintStorage[_key].add(_amount);
    }
    /// @param _key The key for the record
    /// @param _amount An amount to subtract from the record's value
    function subUint(bytes32 _key, uint256 _amount) onlyLatestRocketNetworkContract override external {
        uintStorage[_key] = uintStorage[_key].sub(_amount);
    }
}
/**
  *       .
  *      / \\
  *     |.'.|
  *     |'.'|
  *   ,'|   |`.
  *  |,-'-|-'-.|
  *   __|_| |         _        _      _____           _
  *  | ___ \\|        | |      | |    | ___ \\         | |
  *  | |_/ /|__   ___| | _____| |_   | |_/ /__   ___ | |
  *  |    // _ \\ / __| |/ / _ \\ __|  |  __/ _ \\ / _ \\| |
  *  | |\\ \\ (_) | (__|   <  __/ |_   | | | (_) | (_) | |
  *  \\_| \\_\\___/ \\___|_|\\_\\___|\\__|  \\_|  \\___/ \\___/|_|
  * +---------------------------------------------------+
  * |    DECENTRALISED STAKING PROTOCOL FOR ETHEREUM    |
  * +---------------------------------------------------+
  *
  *  Rocket Pool is a first-of-its-kind Ethereum staking pool protocol, designed to
  *  be community-owned, decentralised, and trustless.
  *
  *  For more information about Rocket Pool, visit https://rocketpool.net
  *
  *  Authors: David Rugendyke, Jake Pospischil, Kane Wallmann, Darren Langley, Joe Clapis, Nick Doherty
  *
  */
pragma solidity 0.7.6;
// SPDX-License-Identifier: GPL-3.0-only
interface RocketStorageInterface {
    // Deploy status
    function getDeployedStatus() external view returns (bool);
    // Guardian
    function getGuardian() external view returns(address);
    function setGuardian(address _newAddress) external;
    function confirmGuardian() external;
    // Getters
    function getAddress(bytes32 _key) external view returns (address);
    function getUint(bytes32 _key) external view returns (uint);
    function getString(bytes32 _key) external view returns (string memory);
    function getBytes(bytes32 _key) external view returns (bytes memory);
    function getBool(bytes32 _key) external view returns (bool);
    function getInt(bytes32 _key) external view returns (int);
    function getBytes32(bytes32 _key) external view returns (bytes32);
    // Setters
    function setAddress(bytes32 _key, address _value) external;
    function setUint(bytes32 _key, uint _value) external;
    function setString(bytes32 _key, string calldata _value) external;
    function setBytes(bytes32 _key, bytes calldata _value) external;
    function setBool(bytes32 _key, bool _value) external;
    function setInt(bytes32 _key, int _value) external;
    function setBytes32(bytes32 _key, bytes32 _value) external;
    // Deleters
    function deleteAddress(bytes32 _key) external;
    function deleteUint(bytes32 _key) external;
    function deleteString(bytes32 _key) external;
    function deleteBytes(bytes32 _key) external;
    function deleteBool(bytes32 _key) external;
    function deleteInt(bytes32 _key) external;
    function deleteBytes32(bytes32 _key) external;
    // Arithmetic
    function addUint(bytes32 _key, uint256 _amount) external;
    function subUint(bytes32 _key, uint256 _amount) external;
    // Protected storage
    function getNodeWithdrawalAddress(address _nodeAddress) external view returns (address);
    function getNodePendingWithdrawalAddress(address _nodeAddress) external view returns (address);
    function setWithdrawalAddress(address _nodeAddress, address _newWithdrawalAddress, bool _confirm) external;
    function confirmWithdrawalAddress(address _nodeAddress) external;
}